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Chan, V. T. W. "Evaluation of the of the C-HA-RAS in human breast disease by nonisotopic hybridization technology." Thesis, University of Oxford, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233535.
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Maguire, Paula. "Investigation of the genetic basis of familial non-BRCA1/2 breast cancer /." Stockholm, 2005. http://diss.kib.ki.se/2006/91-7140-602-6/.
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Erkko, H. (Hannele). "TOPBP1, CLSPN and PALB2 genes in familial breast cancer susceptibility." Doctoral thesis, University of Oulu, 2008. http://urn.fi/urn:isbn:9789514289682.
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The currently known susceptibility genes account for approximately 25% of familial breast cancer predisposition. Additional factors contributing to the pathogenesis of breast cancer are, therefore, likely to be discovered. Most of the known genes affecting breast cancer predisposition function in the DNA damage response pathway. In this study three genes, TOPBP1, CLSPN and PALB2, involved in this complex process were investigated to reveal potentially pathogenic mutations associated with breast cancer susceptibility.
In the analysis of the TOPBP1 gene, one novel putative pathogenic alteration was observed. The Arg309Cys variant was found at an elevated frequency among familial cases (19/125) vs. controls (49/697) (p = 0.002; OR 2.4; 95% CI 1.3–4.2). In addition, altogether 18 other germline alterations were observed in this gene, but they all appeared to be harmless polymorphisms.
Investigation of CLSPN alterations among familial breast cancer families revealed altogether seven different changes. No clearly pathogenic alterations were observed. However, a potential modifier effect was discovered for the 1195delGlu change. The obtained results suggest that CLSPN alterations are unlikely to be significant breast cancer susceptibility alleles.
In the PALB2 gene, a pathogenic mutation c.1592delT was identified at an elevated frequency among breast cancer patients (0.9%) compared to controls (0.2%) (p = 0.003, OR 3.94, 95% CI 1.5–12.1). Among familial cases the frequency of c.1592delT was even higher (2.7%). This mutation was also functionally deficient. It had a markedly decreased BRCA2-binding affinity and was unable to support homologous recombination or to restore cross link repair in PALB2 knock-down cells. Additionally, this mutation was discovered in a familial prostate cancer family and was found to segregate with the disease, suggesting some association also with prostate cancer.
The penetrance and hazard ratio associated with PALB2 c.1592delT were determined in unselected breast cancer families. A substantially increased risk of breast cancer (HR 6.1; 95% CI 2.2–17.2; p = 0.01) was discovered resulting in an estimated 40% (95% CI 17–77) breast cancer risk by age 70 years, comparable to that for carriers of BRCA2 mutations. This markedly increased cancer risk suggests that genetic counselling for carriers is needed and screening for this mutation should be considered.
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Dang, Raymond K. B. "Molecular detection of minimal residual disease in breast cancer and leukaemias using p53 tumour suppressor gene mutations as markers." Thesis, University of Edinburgh, 2000. http://hdl.handle.net/1842/22132.
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The use of peripheral blood progenitor cell (PBPC) transplantation is an important advance in the treatment of breast cancer and acute leukaemias, and these conditions are among the commonest indications for this procedure. Inevitably, there is concern that malignant cells may contaminate progenitor cell harvests and be re-infused during transplantation and cause disease relapse. Various methods are available for the detection of such minimal residual disease (MRD), and the key aim of this project was to evaluate the feasibility of using a tumour-specific marker, namely mutations within the p53 gene, for this purpose. This provided a useful model to assess the feasibility of using subtle genetic changes to detect MRD within PBPC harvests from patients with malignant diseases. The first step involved the use of denaturing gradient gel electrophoresis (DGGE) to screen original tumour tissues for mutations to be used as disease markers, in 5 individually PCR-amplified DNA fragments (A to E) covering exons 5 to 8 of p53. The technique was first optimised using cell lines known to contain p53 mutations in each fragment. Optimisation was performed with respect to electrophoresis temperature, time, voltage and polyacrylamide cross-linker. The sensitivity of DGGE in detecting a mutation in a mixed cell population was determined by diluting tumour cells in wild type (WT) cells. Although the presence of a mutation could be demonstrated when tumour cells occurred as 5% of total, a representation of at least 40% was required for the mutant homoduplex to be isolated for sequencing. Clinical samples studied were from 51 breast cancer patients, 38 of whom had metastatic disease or at high risk of metastasis, and 13 had high risk stage II/III disease randomised in a clinical study investigating PBPC transplantation and adjuvant therapy, and from 29 patients with acute leukaemias. A positive result was obtained in 14 of 51 primary breast cancer patients (1 was positive in 2 different fragments) and 3 of 29 patients with acute leukaemias.
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Karppinen, S. M. (Sanna-Maria). "The role of BACH1, BARD1 and TOPBP1 genes in familial breast cancer." Doctoral thesis, University of Oulu, 2009. http://urn.fi/urn:isbn:9789514291593.
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Approximately 5–10% of all breast cancer cases are estimated to result from a hereditary predisposition to the disease. Currently no more than 25–30% of these familial cases can be explained by mutations in the known susceptibility genes, BRCA1 and BRCA2 being the major ones. Additional predisposing genes are therefore likely to be discovered. This study evaluates whether germline alterations in three BRCA1-associated genes, BACH1 (i.e. BRIP1/FANCJ), BARD1 and TOPBP1, contribute to familial breast cancer.
Altogether 214 Finnish patients having breast and/or ovarian cancer were analysed for germline mutations in the BACH1 gene. Nine alterations were observed, four of which located in the protein-encoding region. The previously unidentified Pro1034Leu was considered a possible cancer-associated alteration as it appeared with two-fold higher frequency among cancer cases compared to controls. All the other observed alterations were classified as harmless polymorphisms.
Mutation analysis of the BARD1 gene among 126 Finnish patients having family history of breast and/or ovarian cancer revealed seven alterations in the protein-encoding region. The Cys557Ser alteration was seen at an elevated frequency among familial cancer cases compared to controls (p = 0.005, odds ratio [OR] 4.2, 95% confidence interval [CI] 1.7–10.7). The other alterations appeared to be harmless polymorphisms. To evaluate further the possible effect of Cys557Ser on cancer risk, a large case-control study was performed, consisting of 3,956 cancer patients from the Nordic countries. The highest prevalence of Cys557Ser was found among breast and ovarian cancer patients from BRCA1/BRCA2 mutation-negative families (p < 0.001, OR 2.6, 95% CI 1.7–4.0). In contrast, no significant association with male breast cancer, ovarian, colorectal or prostate cancer was observed.
The current study is the first evaluating the role of TOPBP1 mutations in familial cancer predisposition. The analysis of 125 Finnish patients having breast and/or ovarian cancer revealed one putative pathogenic alteration. The commonly occurring Arg309Cys allele was observed at a significantly higher frequency among familial cancer cases compared to controls (p = 0.002, OR 2.4, 95% CI 1.3–4.2). The other 18 alterations observed were classified as harmless polymorphisms.
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Solyom, S. (Szilvia). "BRCA/Fanconi anemia pathway genes in hereditary predisposition to breast cancer." Doctoral thesis, Oulun yliopisto, 2011. http://urn.fi/urn:isbn:9789514294099.
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Abstract Two major genes are involved in hereditary predisposition to breast and ovarian cancer – BRCA1 and BRCA2. However, germline mutations in these tumor suppressors account for a maximum 20% of the familial breast cancer cases. A significant portion of the genes predisposing to this disease is unknown and therefore needs to be discovered. The aim of this study was to identify novel breast cancer susceptibility genes from the interweaving BRCA/Fanconi anemia (FA) pathway. Five candidate genes – MERIT40, ABRAXAS, BRIP1, CHK1, and FANCA – were screened for mutations by utilizing conformation-sensitive gel electrophoresis and sequencing, or with multiplex ligation-dependent probe amplification in blood DNA samples of Finnish familial breast cancer patients. Investigation of the MERIT40 gene revealed novel nucleotide changes, being the first report on mutation screening of this gene. None of the observed alterations, however, appeared to be disease related, suggesting that germline mutations in MERIT40 are rare or absent in breast cancer patients. A missense alteration (c.1082G>A, leading to Arg361Gln) was identified in ABRAXAS in 3 out of 125 Northern Finnish breast cancer families (2.4%), but not in any of the 867 healthy controls. The prevalence of the mutation between familial and control cases was statistically significantly different (p=0.002). ABRAXAS c.1082G>A appears to have pathological significance based on its exclusive occurrence in cancer cases, evolutionary conservation, disruption of a putative nuclear localization signal, reduced nuclear localization of the protein, and defective accumulation at DNA damage sites. The BRIP1 (FANCJ) and CHK1 genes were screened for large genomic rearrangements, but no abnormalities were detected, ruling out a significant contribution to breast cancer susceptibility in the Northern Finnish population. A novel large heterozygous deletion was identified in the FANCA gene in one out of 100 breast cancer families, removing the promoter and the first 12 exons. The deletion allele was not present in the tested controls, suggesting that it might contribute to breast cancer susceptibility. This is the first report on the association of a large-size germline deletion in a gene acting in the upstream part of the FA signaling pathway with familial breast cancerTiivistelmä BRCA1 ja BRCA2 ovat kaksi tärkeintä perinnöllisen rinta- ja munasarjasyövän alttiusgeeniä. Niissä esiintyvät ituradan muutokset selittävät kuitenkin vain noin 20 % familiaalisista rintasyöpätapauksista. Suurin osa alttiusgeeneistä on edelleen tunnistamatta ja näitä tekijöitä etsitään aktiivisesti. Tämän tutkimuksen tarkoituksena on ollut tunnistaa uusia alttiustekijöitä toisiinsa läheisesti liittyviltä BRCA/Fanconin anemia (FA) signaalinsiirtoreiteiltä. Viisi kandidaattigeeniä - MERIT40, ABRAXAS, BRIP1, CHK1 ja FANCA – kartoitettiin mutaatioiden suhteen suomalaisissa rintasyöpäperheissä käyttämällä konformaatiosensitiivistä geelielektroforeesia ja sekvensointia, tai multiplex ligation-dependent probe amplification- menetelmää. MERIT40-geenissä havaittiin useita aikaisemmin raportoimattomia nukleotidimuutoksia, mutta yhdenkään niistä ei havaittu liittyvän rintasyöpäalttiuteen. MERIT40-geenimuutosten mahdollista yhteyttä rintasyöpäalttiuteen ei ole tutkittu aikaisemmin. ABRAXAS-geenissä havaittiin missense-mutaatio (c.1082G>A, joka johtaa Arg361Gln aminohappokorvautumiseen) kolmessa pohjoissuomalaisessa rintasyöpäperheessä (3/125, 2.4 %). Muutosta ei havaittu terveissä kontrolleissa (N=867), ja ero mutaation esiintyvyydessä familiaalisten rintasyöpätapausten ja terveiden kontrollien välillä oli tilastollisesti merkitsevä (p=0.002). ABRAXAS c.1082G>A-muutos on todennäköisesti patogeeninen, sillä kyseinen aminohappopaikka on evolutiivisesti konservoitunut ja sijaitsee todennäköisellä tumaanohjaussignaalialueella. Funktionaaliset kokeet osoittivat, että mutatoitunut proteiinituote lokalisoitui villityypin proteiinia heikommin tumaan ja sen ohjautuminen DNA-vaurioalueille oli puutteellista. BRIP1- (FANCJ) ja CHK1-geeneistä etsittiin laajoja genomisia uudelleenjärjestelyjä, mutta niitä ei havaittu. Näin ollen kyseisillä muutoksilla ei ole merkittävää roolia perinnöllisessä rintasyöpäalttiudessa suomalaisessa väestössä. FANCA-geenissä havaittiin laaja heterotsygoottinen deleetio yhdessä tutkitusta 100 rintasyöpäperheestä. Deleetio poistaa geenin promoottorialueen lisäksi sen 12 ensimmäistä eksonia. Deleetioalleelia ei havaittu terveissä kontrolleissa, joten se mahdollisesti liittyy perinnölliseen rintasyöpäalttiuteen. Tutkimus on ensimmäinen, jossa raportoidaan laaja genominen deleetio FA-signaalinsiirtoreitin ylävirran geenissä familiaalisessa rintasyövässä
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Haanpää, M. (Maria). "Hereditary predisposition to breast cancer – with a focus on AATF, MRG15, PALB2, and three Fanconi anaemia genes." Doctoral thesis, Oulun yliopisto, 2014. http://urn.fi/urn:isbn:9789526204581.
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Abstract Around 5−10% of all breast cancer cases are estimated to result from a strong hereditary predisposition to the disease. However, mutations in the currently known breast cancer susceptibility genes account for only 20−30% of all familial cases. Additional factors contributing to the pathogenesis of breast cancer, therefore, await discovery. Aims of this study were to evaluate variations of the AATF and MRG15 genes as novel potential candidates for breast cancer susceptibility, to further examine the prevalence of the cancer-related PALB2 c.1592delT mutation among BRCA-negative high-risk breast cancer families counselled at the Department of Clinical Genetics, Oulu University Hospital, to identify Finnish Fanconi anaemia patients complementation groups as well as causative mutations, and to evaluate the potential role of these mutations in breast cancer susceptibility. The analysis of 121 familial breast cancer cases revealed altogether seven different sequence changes in the AATF gene. However, none of them were considered pathogenic, suggesting that germline mutations in AATF are rare or absent in breast cancer patients. Investigation of the MRG15 gene among familial breast cancer cases revealed seven previously unreported variants, but in silico analyses revealed that none of these variants appeared to modify the function of MRG15. The results suggest that MRG15 alterations are unlikely to be significant breast cancer susceptibility alleles. A previously identified pathogenic PALB2 mutation, c.1592delT, was identified in three patients from a cohort of 62 high-risk BRCA1/2-negative breast cancer patients from the Department of Clinical Genetics. PALB2 c.1592delT mutation testing should thus be a routine part of the genetic counselling protocol, particularly for BRCA1/2-negative high-risk breast cancer patients. Investigation of the complementation groups of Finnish Fanconi anaemia patients revealed a total of six different causative mutations. These mutations were examined further by analysing their prevalence in large cohorts of breast (n=1840) and prostate (n=565) cancers. However, no significant association emerged between cancer predisposition and these FA mutationsTiivistelmä Arviolta 5−10 prosenttia kaikista rintasyöpätapauksista aiheutuu merkittävästä perinnöllisestä alttiudesta sairauteen. Tällä hetkellä tiedossa olevien rintasyövälle altistavien geenivirheiden ajatellaan kuitenkin selittävän vain noin 20−30 prosenttia kaikista perinnöllisistä tapauksista. On todennäköistä, että uusia tekijöitä, jotka osallistuvat rintasyövän patomekanismiin, on vielä löytymättä. Tämän tutkimuksen tarkoituksena oli arvioida AATF- ja MRG15-geeneissä esiintyvien muutosten mahdollista vaikutusta rintasyöpäalttiuteen, tutkia tarkemmin PALB2 c.1592delT -mutaation esiintymistä BRCA-mutaationegatiivisten korkean rintasyöpäriskin potilaiden joukossa (perinnöllisyyspoliklinikka, Oulun yliopistollinen sairaala) ja määrittää suomalaisten Fanconi-anemiapotilaiden komplementaatioryhmät, sairauden taustalla olevat mutaatiot sekä tutkia näihin mutaatioihin mahdollisesti liittyvää rintasyöpäriskiä. 121 familiaalisen rintasyöpätapauksen analyysissä löytyi yhteensä seitsemän erilaista sekvenssimuutosta AATF-geenissä. Näistä yksikään ei kuitenkaan ollut selvästi patogeeninen. Tuloksen perusteella perinnölliset rintasyövälle altistavat muutokset AATF-geenissä ovat joko erittäin harvinaisia tai niitä ei esiinny lainkaan. MRG15-geenin mutaatioanalyysissä havaittiin seitsemän aikaisemmin raportoimatonta muutosta, mutta in silico -analyysien perusteella millään muutoksista ei ole vaikutusta MRG15-proteiinin toimintaan. Tulosten perusteella on epätodennäköistä, että MRG15-geenin muutokset olisivat merkittäviä rintasyövälle altistavia muutoksia. Jo aiemmin patogeeniseksi todettu PALB2 c.1592delT -mutaatio löydettiin kolmelta niistä perinnöllisyyspoliklinikan korkean syöpäriskin 62 potilaasta, jotka olivat BRCA1/2-geenitestauksessa saaneet normaalin tuloksen. Tulostemme perusteella PALB2 c.1592delT -mutaatiotestaus tulisi Suomessa ottaa osaksi perinnöllisyyspoliklinikoiden tarjomaa tutkimusprotokollaa. Suomalaisten Fanconi-anemiapotilaiden komplementaatioryhmiä selvittävässä tutkimuksessa identifioitiin yhteensä kuusi erilaista tautia aiheuttavaa mutaatiota. Näiden muutosten esiintymistä tutkittiin myös laajoissa rinta- (n=1840) ja eturauhassyöpäaineistoissa (n=565). Tilastollisesti merkittävää assosiaatiota ei kuitenkaan todettu suomalaisten FA-mutaatioiden ja syöpäalttiuden välillä
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Lamont, Jayne Margaret. "Radiation induced DNA damage response in carriers of the breast cancer gene mutation BRCA1." Thesis, Lancaster University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289050.
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Jiao, Xiang. "Somatic Mutations in Breast Cancer Genomes : Discovery and Validation of Breast Cancer Genes." Doctoral thesis, Uppsala universitet, Institutionen för immunologi, genetik och patologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-182319.
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Breast cancer is the most common cancer in women worldwide. However, the genetic alterations that lead to breast cancer are not fully understood. This thesis aims to identify novel genes of potential mechanistic, diagnostic or therapeutic interest in breast cancers by mutational analysis and whole-genome sequencing. In paper I, sequencing of 36 previously identified candidate genes in 96 breast tumors with patient-matched normal DNA determined the somatic mutation prevalence of these candidate genes and identified additional mutations in Notch, NF-κB, PI3K, and Hedgehog pathways as well as in processes mediating DNA methylation, RNA processing and calcium signaling. In paper II, comparison of massively parallel mate-pair sequencing results of a human genome before and after phi29-mediated multiple displacement amplification (MDA) revealed that MDA introduces structural alteration artifacts, with an emphasis on false positive inversions, and impairs the sensitivity to detect true inversions. Therefore, MDA has limited value in sample preparation for whole-genome sequencing for structural alteration detection. In paper III, massively parallel paired-end sequencing identified gene rearrangements in 15 hormone receptor negative breast cancers. Forty validated rearrangements were predicted to directly affect 30 genes, involved in epigenetic regulation, cell mitosis, signalling transduction and glycolytic flux. RNA interference-based assays revealed the potential roles in cell growth of some affected genes, among which DDX10 was implicated to be involved in apoptosis. In paper IV, a method for statistical evaluation of putative translocations detected by massively parallel paired-end sequencing was proposed. In an application of this method to analyse translocations detected by cancer genome deep paired-end sequencing, 76 putative translocations were classified into four categories, with the majority likely to be caused by mismapping due to repetitive regions. Taken together, this thesis provides insights into genes and pathways mutated in sporadic breast cancer genomes, which broaden our understanding of the genetic basis of breast cancer and may ultimately facilitate the diagnosis and treatment of this disease.
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Lacerda, Lúcia Maria Wanzeller Guedes de. "Biochemical and molecular genetic studies on gaucher disease in Portugal : the N370S glucocerebrosidae gene mutation." Tese, Porto : Edição do Autor, 1998. http://catalogo.up.pt/F?func=find-b&local_base=UPB01&find_code=SYS&request=000086735.
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Lacerda, Lúcia Maria Wanzeller Guedes de. "Biochemical and molecular genetic studies on gaucher disease in Portugal : the N370S glucocerebrosidae gene mutation." Doctoral thesis, Porto : Edição do Autor, 1998. http://hdl.handle.net/10216/64556.
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Reilly, Drew D. "The Narratives of Young Women with BRCA 1/2 Gene Mutation: A Qualitative Analysis." ScholarWorks@UNO, 2014. http://scholarworks.uno.edu/td/1910.
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A narrative qualitative research design was used to understand the stories of young women diagnosed with BRCA1 and BRCA 2 genetic mutation. Four participants were selected who met the following criteria: (a) the participant is diagnosed with BRCA1 or BRCA2 genetic mutation, b) is within the age range of 18 to 35, (c) is without a cancer diagnosis, and is (d) not currently pregnant and does not have children. The four participants were interviewed through open-ended inquiry. The participants’ narratives proved both similar and dissimilar. The themes were organized into within-case narratives and across-case narratives. The narratives revealed that young BRCA previvors face unique challenges and experiences, and many can be viewed from an underlying feminist lens. In response to the research questions, BRCA previvors revealed detailed narratives, explored issues of family planning, and explained the ways in which BRCA has changed their worldviews.
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Beckler, Daniel. "CORRELATION OF RPOB GENE MUTATION WITH CLINICAL RIFABUTIN AND RIFAMPICIN RESISTANCE FOR TREATMENT OF CROHN'S DISEASE." Master's thesis, University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2770.
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Emerging rise in microbial drug resistance and the slow-growing characteristic of some intracellular pathogens such as MAP (Mycobacterium avium subspecies paratuberculosis) strongly urges the need for an effective approach for unconventional drug susceptibility testing. We designed a molecular-based PCR method for the evaluation of rifabutin (RFB) and rifampicin (RIF) resistance based on probable determinant regions within the rpoB gene of MAP, including the 81 bp variable site located between nucleotides 1363 and 1443. The minimum inhibitory concentration (MIC) for RIF was also determined against 10 MAP isolates in attempt to seek correlation with rpoB sequences. We determined that MAP strain 18 had an MIC > 30 ug/ml and > 5 ug/ml for RIF and RFB respectively, and a significant rpoB mutation C1367T, compared to an MIC of < 1.0 ug/ml for both drugs in the wild type MAP. The 30-fold increase in the MIC was a direct result of the rpoB mutation C1367T, which caused an amino acid change Thr456 to Ile456 in the drug's binding site; the beta subunit of RNA polymerase. Our in vitro induced mutation in MAP strain UCF5 resulted in the generation of a new resistant strain (UCF5-RIF16r) that possessed T1442C rpoB mutation and an MIC > 30 ug/ml and > 10 ug/ml for RIF and RFB respectively. The T1442C mutation resulted in a Leu481 to Pro481 amino acid change, consequently altering the beta subunit sequence. Sequencing the entire 3.5 kb rpoB in strains 18 and UCF5-RIF16r revealed no additional expressed nucleotide mutation. Of the 10 MAP strains analyzed, an additional one strain (UCF4) exhibited a slight increase in the MIC against RIF and RFB compared to the wild-type. Nucleotide sequencing of the rpoB gene revealed an A2284C mutation in strain UCF4 that occurred further downstream of the expected probable rpoB region and resulted in an amino acid alteration Asn762 to His762. The location of this mutation outside the binding site and its correlation with the minor increase in MIC suggests a possible secondary interaction between the drug and the beta subunit. We have provided three dimensional images through the utilization of PyMol Molecular-based Graphics to display a clear comparison of the mutations observed in the beta subunit for MAP strains 18, UCF5-RIF16r, and UCF4. We propose that these alterations may have caused a less stable interaction between RIF and the beta subunit, resulting in the observed increased in MIC. Furthermore, the change in amino acid sequence did not affect the viability for our RIF resistant strains. The data clearly illustrates that clinical and in vitro-induced MAP mutants with rpoB mutations result in resistance to RIF and RFB. Consequently, unconventional drug susceptibility testing such as our molecular approach will be beneficial for evaluation of antibiotic effectiveness. This molecular approach may also serve as a model for other drugs used for treatment of MAP infections.M.S.
Department of Molecular Biology and Microbiology
Burnett College of Biomedical Sciences
Molecular and Microbiology MS
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Kato, Takashi. "Proteinuria-induced chronic kidney disease in the ICGN/Oa mice with a mutation of tensin2 gene." Kyoto University, 2009. http://hdl.handle.net/2433/124287.
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Lawrence, Kirsty Josephine. "Breast cancer predisposition gene BRCA1, pathogenic C61G mutation in mice : synthetic viability in DNA repair and tumour development." Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/7000/.
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The N-terminus of BRCA1 is clinically important as inheritance of a mutation in this region correlates to an increased risk is breast and ovarian cancer. Whilst this is fairly clear, what specific mutations do and the aetiology of the disease is not clear. This thesis investigates N-terminal BRCA1 mutations using both in vitro and cell-based methods with a focus on DNA repair, mainly double-strand break and DNA crosslink repair. The use of chemotherapy agents is used with specific mutations to look at the individual phenotypes these create to each drug or radiation. This thesis also provides evidence on haploinsufficient or dominant negative effects of N-terminal mutations. Overall, the N-terminus of BRCA1 can affect DNA repair and increase genome instability that may lead to tumour development.
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Abdollahian, Mehrnaz. "Estimating Likelihood of Having a BRCA Gene Mutation Based on Family History of Cancers and Recommending Optimized Cancer Preventive Actions." Scholar Commons, 2015. http://scholarcommons.usf.edu/etd/5893.
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BRCA1 and BRCA2 are gene mutations that drastically increase chances of developing breast and ovarian cancers, up to 20-fold, for women. A genetic blood test is used to detect BRCA mutations. Though these mutations occur in one of every 400 in the general population (excluding Ashkenazi Jewish ethnicity), they are present in most cases of hereditary breast and ovarian cancer patients. Hence, it is common practice for the physicians to require genetic testing for those that fit the rules as recommended by the National Cancer Comprehensive Network. However, data from the Myriad Laboratory, the only provider of the test until 2013, show that over 70 percent of those tested are negative for BRCA mutations [1]. As there are significant costs and psychological trauma associated with having to go through the test, there is a need for more comprehensive rules for determining who should be tested. Once the presence of BRCA is identified via testing, the next challenge for both mutation carriers and their physicians is to select the most appropriate types and timing of intervention actions. Organizations such as the American Cancer Society suggest drastic intervention actions such as prophylactic surgeries and intense breast screenings. These actions vary significantly in their cost, cancer incidence prevention ability, and can have major side effects potentially resulting in reproduction inability or death. Effectiveness of these intervention actions is also age dependent.
In this dissertation, both an analytical and an optimization framework are presented. The analytical framework uses supervised machine learning models on extended family history of cancers, and personal and medical information from a recent nationwide survey study of women who have been referred for genetic testing for the presence of a BRCA mutation. This framework provides the potential mutation carriers as well as their physician with an estimate of the likelihood of having the mutations. The optimization framework uses a Markov decision process (MDP) model to find cost-optimal and/or quality-adjusted life years (QALYs) optimal intervention strategies for those tested positive for a BRCA mutation. This framework uses a dynamic approach to address this problem. The decisions are made more robust by considering the variation in estimates of the transition probabilities by using a robust version of the MDP model.
This research study delivers an innovative decision support tool that enables physicians and genetic consultants predict the population at high risk of breast and ovarian cancers more accurately. For those identified with presence of the BRCA mutation, the decision support tool offers effective intervention strategies considering either minimizing cost or maximizing QALYs to prevent incidence of cancers.
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Locke, Imogen. "The evaluation of ductal lavage for risk assessment and early breast cancer detection in BRCA 1/2 gene mutation carriers." Thesis, Institute of Cancer Research (University Of London), 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.510360.
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Gedminaitė, Jurgita. "Krūties vėžiu sergančių moterų BRCA1, BRCA2, CHEK2 ir NBS1 genų mutacijų tyrimas ir jų ryšio su kitais prognoziniais veiksniais paieška." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2013. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2013~D_20130919_143947-94587.
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Apie 5–10 proc. visų krūties navikų atvejų sudaro paveldimas vėžys. BRCA1 ir BRCA2 genai yra patys svarbiausi polinkį susirgti krūties vėžiu sąlygojantys genai. Kiti reikšmingai su padidėjusia krūties navikų išsivystymo rizika susiję – CHEK2 ir NBS1 genai. Šiame darbe ištirtos paveldimos dažniausiai Europos regione nustatomos šių genų mutacijos. Nustatytas BRCA1 ir CHEK2 genų mutacijų dažnis tarp jaunų krūties vėžiu susirgusių moterų, ištyrinėtos jų sąsajos su pacientės amžiumi, naviko klinikinėmis ir morfologinėmis savybėmis. Išanalizuota šeiminės anamnezės prognozinė vertė nustatant paveldimus BRCA1 ir CHEK2 genų pokyčius. Pirmą kartą Lietuvoje įsisavintas CHEK2 bei NBS1 genų tyrimas, nustatyta, kokios CHEK2 geno mutacijos dažniausios. Nors NBS1 geno mutacijų nerasta, bet įsisavinta metodika, kuri bus panaudota ateities tyrimams. Sukurtas kompleksinis BRCA1 bei CHEK2 genų mutacijų radimo prognozavimo modelis. Šiandien klinikinėje praktikoje panašūs modeliai naudojami įvertinti BRCA1/2 genų mutacijų tikimybę. Jų pritaikomumas ir specifiškumas skirtingose etninėse grupėse gali skirtis. Naudojant tirtų pacienčių charakteristikas, įtraukiant ne tik šeiminę anamnezę, pacientės ypatybes, bet ir klinikinius bei molekulinius navikų požymius, sukurti mūsų regionui pritaikyti modeliai bei nustatyti kriterijai, kurie padės atrinkti pacientes genetiniam konsultavimui dėl BRCA1 bei CHEK2 genų mutacijų. Šis naujas požiūris turi didžiulę praktinę naudą.Approximately 5–10% of all breast cancer cases are considered to be hereditary. BRCA1 and BRCA2 genes are the most important breast cancer predisposing genes. Other genes significantly linked with an increased risk of breast tumors are CHEK2 and NBS1 gene. In this scientific work were studied the most prevalent in European region mutations of these genes. The rate of BRCA1 and CHEK2 gene mutations in young women with breast cancer was evaluated and the relationships between these mutations and patient's age, clinical and morphological tumor features are examined. The prognostic value of family history was analyzed when forecasting hereditary BRCA1 and CHEK2 gene mutations. For the first time in Lithuania the CHEK2, NBS1 genes tests were applied and the evaluation of which CHEK2 gene mutations are most prevalent was obtained. Although NBS1 gene mutations were not found, but applied test technique will be used in future research. There was created a prognostic model for determination of BRCA1 and CHEK2 gene mutations. In today's clinical practice similar models are used to assess the likelihood of the BRCA1/2 mutation. Their applicability and specificity in different ethnic groups may vary. Applying the studied data there was created a model adapted to our region. Testing patients, there were considered not only family medical history and personal characteristics, but also the clinical and molecular features of tumors. The criteria have been found which will help in selecting... [to full text]
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Yang, Wei-Shiung. "Functional analysis of the human lipoprotein lipase gene promoter and its naturally-occurring variants /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/10268.
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Good, David Andrew, and n/a. "Genetic Loci for Paget's Disease of Bone." Griffith University. School of Biomolecular and Biomedical Science, 2003. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040319.125358.
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Paget's disease of the bone is a skeletal disorder of unknown cause. This disease is characterised by excessive and abnormal bone remodelling brought about by increased bone resorption followed by disorganised bone formation. Increased bone turnover results in a disorganised mosaic of woven and lamellar bone at affected skeletal sites. This produces bone that is expanded in size, less compact, more vascular, and more susceptible to deformity or fracture than normal bone. Symptoms of Paget's disease may include bone pain, bone deformity, excessive warmth over bone from hypervascularity, secondary arthritis, and a variety of neurologic complications caused in most instances by compression of the neural tissues adjacent to pagetic bone. Genetic factors play a role in the pathogenesis of Paget's disease but the molecular basis remains largely unknown. The identification of the molecular basis of Paget's disease is fundamental for an understanding of the cause of the disease, for identifying subjects at risk at a preclinical stage, and for the development of more effective preventive and therapeutic strategies for the management of the condition. With this in mind, the aim of this project is to identify genetic loci, in a large pedigree, that may harbour genes responsible for Paget's disease of bone. A large Australian family with evidence of Paget's disease was recruited for these studies (Chapter 3). This pedigree has characterised over 250 individuals, with 49 informative individuals affected with Paget's disease of bone, 31 of whom are available for genotypic analysis. The pattern of disease in these individuals is polystotic, with sites of involvement including the spine, pelvis, skull and femur. Although the affected individuals have a severe early-onset form of the disease, the clinical features of the pedigree suggest that the affected family members have Paget's disease and not familial expansile osteolysis (a disease with some similarities to Paget's disease), as our patients have extensive skull and axial skeletal involvement. The disease is inherited as an autosomal dominant trait in the pedigree with high penetrance by the sixth decade. Due to the large size of this family and multiple affected members, this pedigree is a unique resource for the detection of the susceptibility gene in Paget's disease. The first susceptibility loci for Paget's disease of bone have been mapped by other investigators to chromosome 6p21 (PDB1) and 18q21.1-q22 (PDB2) in different pedigrees. Linkage analysis of the Australian pedigree in these studies was performed with markers at PDB1: these data showed significant exclusion of linkage, with LOD scores < - 2 in this region (Chapter 4). Linkage analysis of microsatellite markers from the PDB2 region excluded linkage with this region also, with a 30 cM exclusion region (LOD score < -2.0) centred on D18S42 (Chapter 4). This locus on chromosome 18q21.1-q22 contains a serine protease (serpin) cluster with similarities to chromosome 6p21. Linkage analysis of this region also failed to provide evidence of linkage to this locus (Chapter 4). These data are consistent with genetic heterogeneity of Paget's disease of bone. A gene essential for osteoclast formation encoding receptor activator of nuclear factor-kB (RANK), TNFRSF11A, has been previously mapped to the PDB2 region. Mutations in the TNFRSF11A gene have been identified segregating in pedigrees with Familial Expansile Osteolysis and early onset familial Paget's disease, however, linkage studies and mutation screening have excluded the involvement of RANK in the majority of Paget's disease patients. For the Australian pedigree, mutation screening at the TNFRSF11A locus revealed no mutations segregating with affected individuals with Paget's disease (Chapter 4). Based on these findings, our hypothesis is that a novel susceptibility gene relevant to the pathogenesis of Paget's disease of bone lies elsewhere in the genome in the affected members of this pedigree; this gene should be identifiable using a microsatellite genome-wide scan followed by positional cloning. A genome-wide scan of the Australian pedigree was carried out, followed by fine mapping and multipoint analysis in regions of interest (Chapter 5). The peak 2-point LOD scores from the genome-wide scan were LOD = 2.75 at D7S507 and LOD = 1.76 at D18S70. Two additional regions were also considered for fine mapping: chromosome 19p11-q13.1 with a LOD of 1.58 and chromosome 5q35-qter with a LOD of 1.57. Multipoint and haplotype analysis of markers flanking D7S507 did not support linkage to this region (Chapter 5). Similarly, fine mapping of chromosome 19p11-q13.1 failed to support linkage to this region (Chapter 5). Linkage analysis with additional markers in the region on chromosome 5q35-qter revealed a peak multipoint LOD score of 6.77 (Chapter 5). A distinct haplotype was shown to segregate with all members of the family, except the offspring of III-5 and III-6. Haplotype analysis of markers flanking D18S70 demonstrated a haplotype segregating with Paget's disease in a large sub-pedigree (descendants of III-3 and III-4) (Chapter 5). This sub-pedigree had a significantly lower age at diagnosis than the rest of the pedigree (51.2 + 8.5 vs. 64.2 + 9.7 years, p = 0.0012). Linkage analysis of this sub-pedigree demonstrated a peak two-point LOD score of 4.23 at marker D18S1390 (q = 0.00), and a peak multipoint LOD score of 4.71, at marker D18S70. An implication of these data is that 18q23 harbours a novel modifier gene for reducing the age of onset of Paget's disease of bone. A number of candidate Paget's genes have previously been identified on chromosome 18q23, including the nuclear factor of activated T cells (NFATc1), membrane-associated guanylated kinase (MAGUK) and a zinc finger protein. Candidate gene sequencing of these genes in these studies has failed to identify mutations segregating with affected family members in the sub-pedigree linked to chromosome 18q23 (Chapter 6). More recently, a mutation in the gene encoding the ubiquitin-binding protein sequestosome 1 (SQSTM/p62) has been shown to segregate with affected members of Paget's disease families of French-Canadian origin. In this study, a single base pair deletion (1215delC) was identified as segregating with the majority of affected members in the pedigree (Chapter 6). This deletion introduces a stop codon at amino acid position 392 which potentially results in early termination of the protein and loss of the ubiquitin binding domain. The three affected members of the family that do not share the affected haplotype do not carry a mutation in the coding region of SQSTM/p62. Screening of affected members from 10 further Paget's disease families identified the previously reported P392L mutation in 2 (20%) families. No SQSTM1/p62 coding mutations have been found in the remaining 8 families or in 113 aged matched controls. In conclusion, this project has identified genetic loci and mutations that segregate with individuals affected with Paget's disease. Further investigation of the functional significance of the genetic changes at these loci is expected to lead to a better understanding of the molecular basis of this disease.
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Karicheva, Olga. "Modelling gene therapy for a mitochondrial disease MELAS by exploiting the pathway of RNA mitochondrial import." Strasbourg, 2010. http://www.theses.fr/2010STRA6115.
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Les mutations de l'ADN mitochondrial sont une cause importante de maladies neuromusculaires humaines incurables. Parmi plusieurs mutations répertoriées, plus de 170 sont localisées dans les gènes codant pour les ARN de transfert (ARNt), dont 29 - dans le gène de l’ARNtLeu(UUR) (MT-TL1). La mutation m. 3243A>G de MT-TL1 a été décrite comme une cause majore du syndrome MELAS (myopathie, encéphalopathie, acidose lactique, accidents vasculaires cérébraux). Cette mutation réduit le niveau d’aminoacylation de l’ARNtLeu(UUR) et mène à l’hypomodification de la position « wobble » de son anticodon, ce qui cause des déficiences de la synthèse protéique dans l'organite et une réduction des activités des complexes de la chaîne respiratoire. L’objectif principal de la thèse a été d’étudier si l’expression des ARNt recombinants dans le noyau de cellules transmitochondriales humaines ayant la mutation MELAS m. 3243A>G et leurs adressage dans les mitochondries puisse améliorer les fonctions mitochondriales des cellules touchées par la mutation. Il a été démontré que l'expression des ARNt recombinants est accompagnée par une amélioration de la synthèse protéique mitochondriale, une augmentation du niveau des protéines codées par l’ADNmt et une restauration partielle de la respiration. Ces résultats démontrent la possibilité d’adresser dans les mitochondries les ARNt au potentiel thérapeutique dont la spécificité d’aminoacylation a été changée, et étendent ainsi l’utilisation de l’approche de l’expression allotopique pour le développement de thérapie génique des maladies mitochondrialesMutations in human mitochondrial DNA are often associated with incurable human neuromuscular diseases. Among these mutations, more than 170 have been identified in tRNA genes, including 29 in the tRNALeu(UUR) gene (MT-TL1). The m. 3243A>G mutation in MT-TL1 was described as the major cause of the MELAS syndrome (mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes). This mutation reduces tRNALeu(UUR) aminoacylation level and leads to a hypomodification of the wobble position of its anticodon, which results in a decreased level of mitochondrial protein synthesis and reduced activities of respiratory chain complexes. The thesis was aimed to test if the allotopic expression of recombinant leucine tRNAs in the nucleus of transmitochondrial cybrid cells carrying MELAS m. 3243A>G mutation and their subsequent targeting into mitochondria can rescue mutation-induced dysfunctions. It was shown that expression of specifically designed recombinant tRNAsLeu is accompanied by a significant improvement of mitochondrial translation, an increase of steadystate level of several mtDNA-encoded protein subunits of respiratory chain, and a partial rescue of respiration. These findings prove the possibility to direct into mitochondria tRNAs with changed aminoacylation specificity possessing potential therapeutic activity, thus extending the potential of allotopic expression as the approach to cure mitochondrial disorders
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Huang, Xiangao. "The generation, and the neurochemical and behavioural characterization of transgenic mice carrying the human presenilin-1 gene with or without the Leu235Pro mutation associated with Afzheimer's disease /." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B23440065.
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Pickering, Mary Theresa. "Rb Inactivation Leads to E2F1-mediated DNA Double Strand Break Accumulation: A Dissertation." eScholarship@UMMS, 2006. https://escholarship.umassmed.edu/gsbs_diss/26.
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Although it is unclear which cellular factor(s) is responsible for the genetic instability associated with initiating and sustaining cell transformation, it is known that most, if not all, cancers have mutations that inactivate the Rb-mediated growth control pathway. We show here that acute inactivation of Rb by RNA interference or expression of the E7 viral oncoprotein from human papillomavirus (HPV), and the resultant deregulation of one E2F family member, E2F1, leads to DNA double strand break (DSB) accumulation. These DSBs occur independent of apoptosis induction, and activation of ATM, NBS1, p53, or MAD2, and generation of reactive oxygen species (ROS).
Although ROS accumulation is associated with DSBs generated from the mis-expression of another nuclear oncoprotein, c-MYC, we find that E2F1 does not contribute to c-MYC associated DSBs, indicating that the DSBs associated with these oncoproteins arise through distinct pathways. However, we find that small changes in E2F1 levels by inhibition of c-MYC transactivated microRNAs known to limit E2F1 protein expression, lead to DSB accumulation. These results suggest that despite the DSBs arising by different mechanisms, c-MYC assists in the regulation of E2F1-associated DSBs.
We also find elevated levels of E2F1-associated DSBs in Rb mutated cancer cell lines in the absence of an exogenous DSB stimulus. These basal, E2F1-associated DSBs are substantially lower in Rb wildtype cancer cell lines that have p16ink4 inactivated or express HPV E7. However, we show that we can manipulate DSB levels in these cancer cell lines by modulating Rb and E2F1 activity and suggest that these results may be extended to breast tumor organ culture. Thus, Rb status is key to regulating both the proliferation promoting functions associated with E2F and for preventing DNA damage accumulation if E2F1 becomes deregulated. Taken together, these data suggest that loss of Rb creates strong selective pressure, via DSB accumulation, for inactivating p53 mutations and that E2F1 might contribute to the genetic instability associated with transformation and tumorigenesis.
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黃憲高 and Xiangao Huang. "The generation, and the neurochemical and behavioural characterizationof transgenic mice carrying the human presenilin-1 gene with orwithout the Leu235Pro mutation associated with Afzheimer's disease." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31243149.
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Viljoen, J. E. (Johanna E. ). "The R563Q mutation of the β-subunit of the epithelial sodium channel gene associated with hypertensive disease and related complications in pregnancy." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/5443.
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Thesis (MMed (Obstetrics and Gynaecology))--University of Stellenbosch, 2010.ENGLISH ABSTRACT: Introduction: Hypertensive disease is one of the cardinal causes of maternal morbidity and mortality in South Africa. According to the National Confidential Enquiry into Maternal Deaths (NCEMD) report for 2005-2007, the “big five” causes of maternal death have remained the same as in the previous triennium, with hypertensive disease in second place, being the causative factor in 15.7% of cases.1 Women under 20 years of age were at greater risk of dying due to complications of hypertension. In this light, the early identification and treatment of hypertensive disease remains important priorities in improving maternal care. Various serum markers have been studied to identify women at risk of pre-eclampsia, including biological markers and genetic factors.2 It is also well known that chronic hypertension is one of the major predisposing factors to the development pre-eclampsia.2 A continued search for a genetic screening test to assist in early diagnosis could facilitate a reduction of maternal morbidity and mortality. Aims: The aim of this project is to determine the prevalence of the R563Q mutation of the -subunit of the epithelial sodium channel (-ENaC) gene in a cohort of primigravid women with hypertensive disease in pregnancy and to compare pregnancy outcomes in this group of hypertensive patients to those not identified to be carriers of the mutation. Methodology: A retrospectively collected study cohort of patients with early onset pre-eclampsia, obtained from pooled samples and data from the GAP study (Genetic Aspects of Pre-eclampsia, project number C99/025), was used. The planned sample size was 200, with 200 controls who were ethnic-matched, normotensive women. Exclusion criteria were gestation 34 weeks, multiple pregnancy, known underlying collagen vascular disease and type I Diabetes Mellitus. Outcome criteria: The pregnancy outcomes were analysed with respect to the degree of hypertensive disease and related complications (maternal, placental and neonatal). Results: Blood samples form 104 patients and 80 control samples were analysed. Pre-eclamptic patients were significantly younger than controls (p<0.0001). The presence of the mutation was not significantly increased in the pre-eclamptic group (p=0.33). The mutation bearers did not exhibit a significant tendency towards a specific degree of pre-eclampsia (p=0.51). There were no significant differences in the other studied maternal or fetal outcome measures. A composite outcome (the presence of 1 adverse outcome compared to no adverse outcome) was created which did not differ between the mutation positive and negative pre-eclamptic patients. Data of the index study was combined with the data form a prior relevant study9 and combined odds ratios were calculated. The increased mutation frequency amongst pre-eclamptics compared to healthy controls then remains significant, OR 2.57(95%CI 1.23-5.36). Conclusion: In this study the R563Q mutation of the ß-subunit of the epithelial sodium channel gene was not linked to pre-eclampsia. No significant negative correlation could be established between the presence of the R563Q mutation and the outcomes of pre-eclampsia. Further research aimed at chronic hypertensive patients in pregnancy and unstable pre-eclampsia in larger study groups could shed more light on the relation between the mutation and the pre-eclamptic phenotype.
AFRIKAANSE OPSOMMING: Inleiding: Hipertensie-verwante siektes is een van die hoof oorsake van moederlike morbiditeit en mortaliteit in Suid-Afrika. Volgens die Nasionale Vertroulike Ondersoek insake Moederlike Sterftes (NCEMD) verslag vir 2005-2007, is die “groot vyf” oorsake van moedersterftes dieselfe as in die vorige triënnium, met hipertensie-verwante siektes in tweede plek, as die oorsaak van 15.7 % van die sterfgevalle. 1 Vroue jonger as 20 jaar het ‘n groter risiko om te sterf aan die komplikasies van hipertensie-verwante siektes. In die lig hiervan is die vroeë identifikasie en behandeling van hipertensie-verwante siektes ‘n priorteit in die verbetering van moedersorg. Verskeie serum merkers is al bestudeer met die hoop om vroue met verhoogde risiko vir die ontwikkelling van pre-eklampsie te identifiseer, wat biologiese merkers en genetiese faktore insluit. 2 Dit is ook welbekend dat chroniese hipertensie een van die hoof predisponerende faktore is vir die ontwilkkeling van pre-eklampsie.2 ‘n Voortgesette soektog na ‘n genetiese siftingstoets wat kan bydra tot vroeë identifisering, sou moederlike morbiditeit en mortaliteit kon verminder. Doelwittle: Die doelwit van hierdie projek is om die prevalensie van die R563Q mutasie van die -subeenheid van die epiteliële natrium kanaal (-ENaC) geen te bepaal in ‘n kohort primigravida vroue met hipertensie-verwante siekte in swangerskap en om die swangerskapsuitkomste van hierdie groep te vergelyk met pasiente wat nie draers van die mutasie is nie. Metodologie: ‘n Retrospektief versamelde studie kohort met vroeë aankoms pre-eklampsie, verkry van die monsterbank en data van die GAP studie (Genetic Aspects of Pre-eclampsia, projek nommer C99/025) is gebruik. Die beplande steekproef grootte was 200, met 200 kontroles, wat etnies- en ouderdomvergelykbare normotensiewe vroue was. Uitsluitingskriteria was gestasie 34 weke, onderliggende bindweefselsiekte en tipe I Diabetes Mellitus. Uitkomskriteria: Swangerskap uitkomste was geanaliseer met betrekking tot die graad van hipertensiewe siekte en verwante kompliksies (moederlik, plasentaal en neonataal). Resultate: Bloed monsters van 104 pasiënte en 80 kontroles is ontleed. Pre-eklampsie pasiënte was betekenisvol jonger as kontroles (p<0.0001). Die teenwoordigheid van die mutasie was nie betekenisvol verhoog in die pre-eklampsie groep nie (p=0.33). Die mutasie-draers het nie ‘n geneigdheid tot ‘n spesifieke graad van pre-eklampsie getoon nie (p=0.51). Daar was geen betekenisvolle verskille tussen die ander moederlike of fetale uitkomste wat bestudeer is nie. ‘n Gesamentlike uitkoms (teenwoordigheid van 1 swak uitkoms vergeleke met geen swak uitkoms) is geskep; daar was geen verskil tussen die mutasie-positief en negatiewe pasiënte met pre-eklampsie nie. Data van die indeks studie en relevante data uit ‘n vorige studie9 is saamgevoeg en die gesamentlike kansverhouding is bereken. Die verhoogde mutasie frekwensie onder pasiënte met pre-eklampsie vergeleke met gesonde kontroles was betekenisvol, KV 2.57(95%VI 1.23 - 5.36). Gevolgtrekking: In hierdie projek was daar nie ‘n verband tussen die R563Q mutasie van die -subeenheid van die epiteliële natrium kanaal (-ENaC) geen en pre-eklampsie nie. Geen betekenisvolle negatiewe korrelasie tussen die R563Q mutasie en pre-eklampsie uitkomste kon aangetoon word nie. Verdere navorsing gerig op pasiënte met chroniese hipertensie of akute, onstabiele pre-eklampsie in groter studiegroepe kan die verband tussen die mutasie en die pre-eklampsie fenotipe moontlik beter toelig.
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Rouault, Audrey. "Etude génomique des cancers du sein familiaux liés à une mutation constitutionnelle du gène BRCA2." Thesis, Bordeaux 2, 2013. http://www.theses.fr/2013BOR22122/document.
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L’altération constitutionnelle des gènes BRCA1 et BRCA2 est détectée dans 20 à 30% des formes familiales de cancer du sein. La fréquence de mise en évidence d’une mutation BRCA2 selon des critères généalogiques reste modeste. La définition de caractéristiques tumorales communes aux tumeurs du sein survenant dans un contexte de prédisposition lié à BRCA2 a pour objectif l’identification de caractéristiques propres aux tumeurs BRCA2 permettant de mieux définir les indications de recherche de mutation de ce gène, et l’identification de facteurs impliqués dans la tumorigénèse des cancers du sein liés à BRCA2. L’étude des profils génomiques des tumeurs BRCA2 a caractérisé la délétion récurrente des bras longs des chromosomes 13 et 14. L’analyse supervisée des données d’expression entre les tumeurs BRCA2 et les tumeurs familiales BRCAX a identifié une signature spécifique des tumeurs BRCA2. Les exomes des chromosomes 13 & 14 pour 5 tumeurs informatives et leur ADN constitutionnel ont été séquencés afin d’identifier la ou les cibles des régions délétées. Cette analyse a permis la caractérisation de variants somatiques qui seront à étudier dans une large série de cas BRCA2 et contrôles pour conclure sur leur rôle dans la tumorigénèse liée à BRCA2.La caractérisation de pertes de matériel chromosomique spécifiques aux tumeurs BRCA2, rapportée dans plusieurs études, offre une perspective diagnostique avec le développement d’un test FISH utilisable en pratique clinique pour préciser les indications d’une recherche de mutation du gène BRCA2, mais suggère également la présence de gènes cibles candidats dont l’inactivation est requise lors de la cancérisation mammaire liée à BRCA2Germline BRCA1 and BRCA2 mutations account for 20-30% of familial breast cancer. The main indication for BRCA2 screening is a family history, but the mutation detection rate in patients selected this way is low. The identification of characteristics common to BRCA2-associated tumors would improve the criteria used to select patients for BRCA2 screening and could identify factors implicated in BRCA2-mutant breast cancer tumorigenesis. The analysis of BRCA2-mutant breast tumor genomic profiles identified deletions of chromosomes 13q and 14q as a common feature of BRCA2-tumors. Supervised gene expression analysis of BRCA2-mutant breast tumors and familial breast tumors without germline BRCA1 or BRCA2 mutations identified a specific BRCA2 gene signature. Exome sequencing of chromosomes 13q and 14q for 5 BRCA2-mutant tumors, and their associated germline DNA was performed in order to identify the target(s) of the specific genomic deletions in the BRCA2 tumors. This analysis characterized somatic variants that will be screened for in a larger cohort of BRCA2 and control tumors cases to explore their role in BRCA2-mutant breast cancer. Our study identified deletions of chromosomes 13q and 14q as a common feature of tumors with germline BRCA2 mutations, as has been observed in several previous studies. We suggest that FISH analysis for the deletion of these chromosomes would be a rapid and technically feasible first step to select tumors worth screening for germline BRCA2 mutations and we hypothesize that the inactivation of candidate genes located in these deleted regions allows the cell to resume division and progress thus contributing to tumorigenesis in BRCA2-mutant tumors
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Weber, Jérémie. "Nouvelle méthode de détection de mutations inconnues : applications au diagnostic génétique." Paris 6, 2005. http://www.theses.fr/2005PA066560.
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Oliveira, Nicássia de Sousa. "Caracterização fenotípica do camundongo mutante bate palmas induzido pelo agente mutagênico químico ENU (N- Ethyl- N- Nitrosourea) como potencial modelo para a síndrome de Kabuki." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/10/10133/tde-01122017-162348/.
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O camundongo mutante denominado bate palmas (BALB/cbapa) originou-se de mutagênese química induzida por N-ethyl-N-nitrosourea (ENU). Suas principais características fenotípicas são alterações posturais com movimentos anormais dos membros posteriores quando suspenso pela cauda, simulando o ato de bater palmas. A partir do padrão de herança a mutação foi identificada como autossômica recessiva. Os resultados do sequenciamento do exoma apontaram como forte candidato o gene lysine (K)-specific methyltransferase 2D (kmt2d, também conhecido como mll2 ou mll4), localizado no cromossomo 15 do camundongo. Essa mutação foi confirmada através de sequenciamento do DNA pelo método de Sanger. A perda da função do gene KMT2D, localizado no cromossomo 12 em humanos, foi descrita como responsável pela síndrome de Kabuki, que é uma anomalia congênita rara, autossômica dominante, também conhecida como síndrome Niikawa-Koruki. O fenótipo clínico da doença é variável, mas algumas características mais comuns são face dismórfica, anormalidades esqueléticas, alterações dermatoglíficas, leve a moderado retardo mental e retardo do crescimento pós-natal. O presente estudo teve como objetivo caracterizar o fenótipo do camundongo mutante bate palmas a partir da análise de parâmetros comportamentais. Para tanto, foram utilizados 30 camundongos mutantes bate palmas- sendo 15 machos e 15 fêmeas- e seus respectivos controles BALB/c, com oito semanas de idade no início dos experimentos. Os testes comportamentais foram realizados em ordem crescente de estresse e ordenados na seguinte sequência 1) observação direta em campo aberto dos parâmetros da atividade geral, sensoriais, psicomotores e os ligados ao sistema nervoso central e autônomo; 2) ansiedade e memória no teste do labirinto em cruz elevada; 3) memória operacional no teste do labirinto em T; 4) coordenação motora no teste da trave elevada e 5) comportamento do tipo depressivo nos testes de suspensão pela cauda e natação forçada. Os dados obtidos no presente estudo demostraram que o mutante bate palmas apresentou aumento na frequência de levantar em ambos os sexos, sugerindo comportamento estereotipado; no entanto, não houve alteração na atividade geral. Na avaliação do sistema sensorial houve redução no reflexo auricular e na resposta de aperto de cauda do mutante bate palmas. Em relação aos parâmetros psicomotores houve diminuição do reflexo de endireitamento e queda do trem posterior, sugerindo deficiência motora, como a hipotonia. Os resultados do teste de labirinto em cruz elevada identificaram menor nível de ansiedade nos mutantes em comparação aos controles. Ainda, as respostas observadas no segundo dia do teste mostraram que não houve perda de memória dos bate palmas. Além disso, o teste do labirinto em T mostrou que não houve alteração na memória espacial dos camundongos mutantes em relação aos BALB/c. Já os resultados dos testes de suspensão pela cauda e de natação forçada foram semelhantes, indicando maior tempo de imobilidade dos mutantes em comparação aos BALB/c. Analisados em conjunto, os resultados desse estudo sugerem que o mutante bate palmas apresentou alterações nos parâmetros sensoriais e psicomotores e possível comportamento estereotipado, relacionadas à mutação do gene kmt2d.The mutant mouse denominated bate palmas (BALB/cbapa) originated from chemical mutagenesis induced by N-ethyl-N-nitrosourea (ENU). Its main phenotypic characteristics are postural alterations with abnormal movements of the hind limbs when suspended by the tail, simulating the act of clap hands. The inheritance pattern of the mutation was identified as autosomal recessive. The potential candidate gene lysine (K) -specific methyltransferase 2D (kmt2d, also known as mll2 or mll4), located on chromosome 15 of the mouse, was identified by the exome sequencing. This mutation was confirmed by DNA sequencing by the Sanger method. The loss of function of KMT2D gene, located on chromosome 12 in humans, has been described as responsible for Kabuki syndrome, which is a rare congenital anomaly, autosomal dominant, also known as Niikawa-Koruki syndrome. The clinical phenotype of the disease is variable, but some common features are dysmorphic face, skeletal abnormalities, dermatoglyphic changes, mild to moderate mental retardation and postnatal growth retardation. The present study aimed to characterize the phenotype of the mutant mouse bate palmas from the analysis of behavioral parameters. Therefore, 30 mutant mice were used - 15 males and 15 females - and their respective BALB/c controls, at eight-wk-old at the beginning of the experiments. Behavioral tests were performed in increasing order of stress and ordered in the following sequence: 1) direct observation in the open field of the parameters linked to general activity, sensorial and psychomotor systems, and those connected to the central and autonomic nervous system; 2) anxiety and memory in the elevated plus maze test; 3) operating memory in the T-maze test; 4) motor coordination in the balance beam test, and 5) depressive-like behavior in the tail suspension and forced swimming tests. The data obtained in the present study demonstrated that the mutant bate palmas presented increase in the rearing frequency in both sexes, suggesting stereotyped behavior; however, there was no change in the general activity. The evaluation of the sensory system demonstrated reduction in the auricular reflex and the tail flick response of the mutant bate palmas. Regarding to the psychomotor parameters, there were observed impairments in the surface-righting reflex and hindquarter fall, suggesting motor deficiency, such as hypotonia. The results of the elevated plus maze test identified a lower level of anxiety in the mutants compared to controls. Still, the responses observed on the second day of the test showed that there was no loss of memory of the bate palmas. In addition, the T-maze test showed that there was no change in the spatial memory of the mutant mice in relation to BALB/c mice. Data of the tail suspension and forced swimming tests were similar, indicating a longer immobilization time of the mutants compared to BALB/c mice. Taken together, the results of this study suggest that the mutant bate palmas showed impairments of the sensorial and psychomotor parameters, and possibly stereotyped behavior related to the mutation of the kmt2d gene.
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ROSENBLATT, NATHALIE, and Francis Loor. "Le syndrome murin gld (generalized lymphoproliferative disease) (mutation d'un gene codant pour un ligand inducteur d'apoptose) : caracterisation de la lymphoproliferation et essais de correction du s." Université Louis Pasteur (Strasbourg) (1971-2008), 1994. http://www.theses.fr/1994STR13171.
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La mutation gld (generalized lymphoproliferative disease), affectant le gene codant pour le ligand de l'antigene fas, induit chez les souris mutees, une lymphoproliferation et un etat autoimmun. La lymphoproliferation des souris gld resulte de l'accumulation dans la rate et les ganglions, de cellules t, possedant un phenotype membranaire inhabituel, puisqu'elles expriment a la fois le marqueur des cellules t, thy1, et le marqueur des cellules b, b220. Une partie des travaux decrits dans cette these etait destinee a elucider l'etiologie de ce syndrome lymphoproliferatif. Ainsi, nous avons montre que la differenciation des cellules t gld en cellules thy1#+b220#+ etait dependante du thymus et du degre d'activation des cellules b gld. Une autre partie de nos resultats tendait a determiner les causes de l'autoimmunite des souris gld. Le syndrome autoimmun des souris gld est caracterise par des taux eleves d'auto-anticorps et d'immunoglobulines. La construction et l'analyse des sera des souris b6 (nu/nu, gld/gld), qui associent a la mutation gld, la mutation nude, ont revele que les cellules b gld n'etaient pas intrinsequement affectees par la mutation gld. Ainsi, l'autoimmunite des souris gld resulterait plutot d'une hyperactivation des cellules b par les cellules t gld, ces dernieres etant intrinsequement touchees par la mutation gld. Des lors, nos resultats associes a l'identification genetique de la mutation gld, nous ont permis de progresser dans la comprehension du developpement du syndrome gld
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Levy, Claudia Bustamante. "Análise de mutações no gene TP53 em casos de câncer de mama e estudo da proteína p53 mutante: aspectos fisiopatológicos do tumor." Universidade do Estado do Rio de Janeiro, 2010. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=1772.
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O câncer de mama é o tipo mais frequente de neoplasia maligna entre as mulheres, com a incidência de mais de um milhão de novos casos no mundo, por ano. O gene TP53 é responsável por regular o destino da célula em resposta a estresses genotóxicos e não genotóxicos. Mutações somáticas neste gene são encontradas em, aproximadamente, 50% dos carcinomas humanos. No câncer de mama, a frequência das mutações no TP53 é em torno de 20 a 50%, sendo a alteração mais encontrada. Estas mutações podem alterar a conformação da proteína, prejudicando sua função de ativadora da transcrição de genes alvo e, pode levar a p53 a apresentar tendência à agregação. Neste trabalho, foi realizado a análise da presença de mutações nos exons 5 a 10 do gene TP53, em biópsias de câncer de mama, de mulheres residentes na cidade do Rio de Janeiro. Após a identificação das amostras com mutação em TP53, algumas foram selecionadas para se verificar o comportamento das diversas mutantes quanto à formação de agregados de p53, em cortes histológicos dos tumores de mama. Foram utilizados os anticorpos A11 e DO1, que reconhecem oligômeros pré-fibrilares e a p53 mutante ou selvagem, respectivamente. Para tanto, foi utilizado o ensaio de co-localização por imunofluorescência, utilizando microscópio confocal para a observação dos resultados. Mutações no gene TP53 foram detectadas em 19% dos casos analisados de câncer de mama sendo 88,2% do tipo ―missense‖. Estas mutações, em tumores do tipo carcinoma ductal infiltrante (CDI), estavam associadas a um estágio mais tardio e agressivo de câncer, representado pelo Grau III de Elston (p< 0,0001). Também foi observada relação positiva dos tumores com mutações e o acúmulo da p53 (p= 0,0184). Além disso, foi observado um padrão diferente das mutantes de p53 quanto à tendência a agregação, sendo as mutantes R273H e P278A as que apresentaram uma maior agregação. Assim, a agregação da p53 mutante observada ―in vivo‖ e descrita nesta dissertação, parece depender do tipo de mutação observada nos casos de câncer de mama.Breast cancer is the most frequent cancer in women, with 1 million of new cases in the world each year. The TP53 gene is responsible for the regulation of the cells fate in response to genotoxic and non-genotoxic stress. Somatic TP53 mutations are found in, approximately, 50% of human cancers. In breast cancer, TP53 mutation is the most frequent genetic alteration, being present in 20 to 50% of cases. These mutations may change the protein conformation, impairing the transcription of target genes, and may lead the mutant p53 to aggregate. In this study, we analyzed the presence of mutations in exons 5-10 of TP53 in breast cancer biopsies of women resident in the metropolitan area of Rio de Janeiro. After the determination of samples with mutation, some of them were selected to investigate the behavior of different mutants in the formation of p53 aggregates in tumors using A11 and DO-1 antibodies, which recognizes pre-fibrillar oligomers and mutant or wild-type p53, respectively. So, we utilized a immunofluorescence co-localization assay using confocal microscope. TP53 mutations were detected in 19% of the breast cancer cases, with 88.2% of missense type. These mutations, in tumors classified as infiltrating ductal carcinoma (CDI), were associated with a later and aggressive stage of cancer, represented by Elstons Grade III (p< 0.0001). A relation was also observed between these mutations and p53 accumulation (p= 0.0184). Furthermore, a different pattern of p53 mutants for the tendency to aggregate was observed and we detected that the mutants R273H and P278A showed a greater aggregation. Thus, the mutant p53 aggregation observed in vivo and described in this study, seems to depend on the type of mutation found in breast cancer cases.
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Hummes, Frieder Taurai [Verfasser]. "The Effects of Endurance Exercise on Lactatedehydrogenase-A and Lactatedehydrogenase-B Gene Expression in Skeletal Muscle of Asymptomatic and Symptomatic Huntington's Disease Mutation Carriers / Frieder Taurai Hummes." Ulm : Universität Ulm, 2021. http://d-nb.info/123814764X/34.
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Frade, Proud'hon-Clerc Sara. "Recherche de nouvelles mutations génétiques à effet majeur dans la maladie de Crohn." Thesis, Lille 2, 2019. http://www.theses.fr/2019LIL2S016/document.
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Le gène NOD2, impliqué dans les réponses immunitaires innées contre le peptidoglycane bactérien, est étroitement associé à la maladie de Crohn (MC) avec des Odd Ratio(OR) allant de 3 à 36 selon le génotype et a été initialement identifié par des analyses de liaisons génétiques. Les données des familles multiplexes (familles définies par la présence de trois ou plus de trois apparentés au premier degré atteints de MC) issues du registre EPIMAD ont été analysées. Il a été précédemment rapporté que dans les 22 familles multiplexes EPIMAD génotypées pour les 3 mutations majeures du gène NOD2une fréquence élevée de ces mutations du gène NOD2 : R702W, G908R et L1007fs, pouvait expliquer la fréquence élevée de MC dans ces familles. Cependant, quelques familles multiplexes EPIMAD ne présentaient aucune de ces mutations R702W, G908R et L1007fs.Afin d’identifier de nouvelles variations génétiques ayant un effet majeur dans la MC, un protocole de Whole Exome Séquencing (WES) a été effectué sur l’une de ces familles multiplexes EPIMAD (F49M) présentant quatre sujets atteints de MC sur deux générations.Une variation rare du gène NOD2, N1010K, s’est avérée présente chez tous les patients atteints et absente chez tous les sujets contrôles intrafamiliaux . L’évaluation in silico et la modélisation 3D ont mis en évidence un effet délétère hautement probable de la mutation de N1010K suggérant donc fortement qu’elle pourrait être un nouveau facteur de risque majeur impliqué dans la susceptibilité génétique à la maladie de Crohn. Elle pourrait expliquer l’agrégation familiale de la MC dans la famille analysée. La présence d’une maladie plus sévère chez les patients hétérozygotes composites N1010K/L1007fs plaide en faveur de l’effet délétère de la mutation N1010K.En plus de la caractérisation d’une nouvelle mutation rare du gène NOD2, 2 autres variants potentiels ont été identifiés : les mutations D359H et G33V respectivement des gènes BPIFB2 et DEFB132. Les protéines codées par ces gènes sont impliquées dans les mêmes voies de signalisation : la voie de signalisation des défensines ainsi que dans celle du système immunitaire inné. L’évaluation in silico des effet de ces mutations a mis en évidence un effet délétère hautement probable pour D359H et G33V des gènes BPIFB2et DEFB132. Ainsi, on peut supposer que bien que les deux mutations D359H du gèneBPIFB2 et G33V du gène DEFB132, soient localisés sur deux gènes différents impliquées dans les mêmes voies de signalisation, elles pourraient agir ensemble et conduire à un effet dysfonctionnel cumulatif impliqué également dans l’agrégation familiale de la MC dans la famille F49M.Ainsi, Pour la famille F49M, l’agrégation familiale pourrait reposer sur l’accumulation de plusieurs mutations à effet délétère (N1010K, D359H et G33V)The NOD2 gene, involved in innate immune responses, has been found to be highlyassociated with Crohn’s Disease (CD). EPIMAD multiplex families with three or more CDaffectedmembers were previously reported to be related to a high frequency of NOD2gene mutations : R702W, G908R, and L1007fs. However, some rare EPIMAD CD multiplexfamilies were described without any of the common NOD2 linked-to-disease mutations.In order to identify new genetic variation(s) with amajor effect in CD, whole exomesequencing was performed on available subjects in a multiplex family (F49M), withoutknown common NOD2 mutations and comprising four patients affected with Crohn’s diseaseand three unaffected related subjects on two generations . A rare and, not yet, reportedmissense mutation of the NOD2 gene, N1010K, was detected and co-segregated acrossaffected patients (present in allmembers affectedwith CD and absent in all unaffected familialcontrol subjects). In silico evaluation of the deleterious effect of the mutation and3D modelling highlighted evidences for an adverse effect of the N1010K mutation withregard to the function of the NOD2 protein and the genetic risk of CD.Moreover, N1010Kand L1007fs as a compound heterozygous state in two, more severe CD family membersstrongly suggests that N1010K could be a new risk factor involved in Crohn’s disease geneticsusceptibility.In addition to the characterization of a new rare mutation of the NOD2 gene, 2 otherpotential variants have been identified : the D359H and G33V mutations, respectively, inthe BPIFB2 and DEFB132 genes. The proteins encoded by these genes are involved in thesame pathways : the pathway of defensins and the pathway of the innate immune system.In silico evaluation of the deleterious effect of mutations revealed a potential deleteriouseffect of D359H and G33V mutations. Thus, we could hypothesize that although the two mutations D359H and G33V are located on two different genes but involved in the same signaling pathways, they could act together and determine a cumulative dysfunctional effect also involved as determinants of the familial aggregation of Crohn’s disease in family F49M.Thus, for the F49M family, familial aggregation could be based on the accumulation of several deleterious mutations (N1010K, D359H and G33V)
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Van, der Merwe Celia. "An investigation into the role of mitochondrial dysfunction in South African Parkinson’s disease patients." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/71647.
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Thesis (MScMedSC)--Stellenbosch University, 2012.Bibliography
ENGLISH ABSTRACT: Parkinson’s disease (PD) is a neurodegenerative movement disorder characterized by the loss of dopaminergic neurons in the substantia nigra of the midbrain. Although the aetiology of PD is still not fully understood, it is thought to involve a combination of environmental (such as exposure to pesticides and neurotoxins) and genetic factors. A number of PD-causing genes have been found including SNCA, LRRK2, EIF4G1 and VPS35 (for autosomal dominant forms of PD) and parkin, PINK1, DJ-1 and ATP13A2 (for autosomal recessive forms of PD – arPD). Mutations in the parkin gene are the predominant cause of arPD. Parkin plays a role in the ubiquitin-proteasomal system which degrades damaged and unwanted proteins in the cell and it is also thought to be involved in maintaining healthy mitochondria. Numerous studies have implicated mitochondrial function in the pathogenesis of PD. Therefore the aim of the present study was to investigate the role of mitochondrial dysfunction in PD patients with parkin-null mutations. Four South African PD patients, each harbouring two parkin-null mutations, were recruited for this study. A muscle biopsy was performed for analysis of mitochondrial morphology using histology and transmission electron microscopy (TEM). Skin biopsies were taken, from which fibroblasts were cultured. These fibroblasts were used in i) mitochondrial morphological assessments using TEM, ii) mitochondrial network analysis, iii) functional studies via ROS measurement and iv) analysis of the proteome using a LTQ Orbitrap Velos mass spectrometer. In addition, RNA was isolated from peripheral blood samples for gene expression studies using the RT² Profiler PCR Array (SABiosciences, USA) and the RT² PCR Primer Assay (SABiosciences, USA). Heterozygous family members (carriers) and wild-type controls were also recruited for this study. Results from the histological and TEM analysis from the muscle biopsy observed subtle mitochondrial changes including the presence of type II fibres, atrophic fibres, the presence of lipids, and wrinkling of the sarcolemmal membrane. Enlarged mitochondria were also observed in one patient. TEM analysis on the patient’s fibroblasts observed an increase in the number of electron dense vacuoles, speculated to be autolysosomes. The mitochondrial network in two of the patients’ fibroblasts showed fragmented and dot-like networks which are indicative of damaged mitochondria. An increase in mitochondrial ROS levels was observed in three of the four patients. Expression studies found down-regulation of 14 genes from four of the five mitochondrial complexes and a total of 688 proteins were found only in the control and not in the patient fibroblasts. Some of these proteins are known to be part of the ‘mitochondrial dysfunction’ pathway. Taken together, these results indicate that the absence of parkin results in a number of mitochondrial alterations. Based on these findings, a model of PD was proposed: It is speculated that when parkin is absent, electron transport chain complex genes are down-regulated. This results in impaired oxidative phosphorylation, causing an increase in the production of mitochondrial ROS and subsequent oxidative stress. Mitochondria are then damaged; resulting in the fragmentation of the mitochondrial network. The impaired mitochondria are thus tagged for degradation, causing the recruitment of autolysosomes which engulf the mitochondria via mitophagy. Ultimately, as the compensatory mechanisms fail, this triggers the consequential cascade of cellular apoptotic events. This study has elucidated the effect of parkin on the mitochondria, and can act as a ‘stepping stone’ towards future development of therapeutic strategies and/or biochemical markers that will benefit not only patients with PD but also other neurodegenerative disorders.
AFRIKAANSE OPSOMMING: Parkinson se siekte (PS) is ‘n neurodegeneratiewe bewegings-afwyking gedefineer deur die verlies van dopaminergiese neurone in die substantia nigra van die midde brein. Alhoewel die spesifieke oorsprong van die afwyking nog nie ten volle begryp is nie, word bydraes van beide omgewings faktore (bv. blootstelling aan plaagdoders en neurotoksienes) asook genetiese faktore gespekuleer. Vanuit ‘n genetiese aspek is ‘n aantal gene al geassosieer met PS. Hierdie gene sluit in SNCA, LRRK2, EIF4G1 en VPS35 (vir outosomale dominante vorms van PS) en parkin, PINK1, DJ-1, en ATP13A2 (vir outosomale resessiewe vorms van PS - orPS). Mutasies in die parkin geen is aangedui as die hoof oorsaak van orPS. Parkin speel ‘n rol in die ubiquitine-proteasomale sisteem wat beskadige en ongewensde proteïne binne in die sel verwyder en is verdink om by te dra tot die instandhouding van gesonde mitokondria. Mitokondriese wanfunksionering is ook deur talle studies gewys as ‘n bydraende faktor in die patologie van PS. Die doel van die studie is om ondersoek in te stel tot die spesifieke rol wat mitokondriese wanfunsionering speel in PS pasiënte met parkin-nul mutasies. Vier Suid-Afrikaanse PS-pasiënte, elk met twee parkin-nul mutasies, is gebruik vir die studie. Deur middel van spierbiopsies is monsters verkry vir mitokondriese morfologiese analises met behulp van histologiese en elektron-oordrag mikroskopie tegnieke (TEM). Vel biopsies is ook geneem en fibroblaste is gekweek vir die gebruik in: i) mitokondriese morfologiese assesering; ii) mitokondriese netwerk analiese; iii) funksionele studies waar vlakke van reaktiewe suurstof spesies (ROS) gemeet is; iv) proteoom analiese met behup van ‘n LTQ Orbitrap Velos massa spektrometer. RNA is ook geisoleer vanaf perifere bloedmonsters vir die gebruik in geen-uitdrukkings studies met behulp van ‘n RT² Profiler PCR Array en ‘n RT² Primer Assay. Selle vanaf famielie lede wat heterosigotiese draers is van die mutasie, asook normale (geen parkin mutasie) selle is gebruik as kontroles in die studie. TEM resultate vanaf die spier monsters het subtiele mitokondriese veranderinge getoon. Hierdie sluit in die teenwoordigheid van tipe II vesels, atrofiese vesels, teenwoordigheid van lipiedes, assook waarnemings van rimpeling van die sarcolemmal membraan. Vergrote mitokondrias is ook in een van die pasiënte opgelet. TEM resultate vanaf die fibroblaste het toename in die aantal elektron-digte vakuole vertoon, moontlik geidentifiseer as autolisosome. Gefragmenteerde en onderbreekte mitokondria netwerke is gelet tydens netwerk analiese van die fibroblaste, ‘n indikasie van beskadigde mitokondria. ‘n Toename in mitokondriese ROS vlakke is gevind in drie van die vier pasiënte. Af-regulering van 14 gene, geassosieerd met vier uit die vyf mitokondria komplekse, is verneem tydens die geen-uitdrukkings studie. Saam met dit is ‘n totaal van 688 proteïene geidentifiseer wat slegs teenwoordig is in die kontrole monsters en nie in die pasiënt monsters nie. Hierdie proteïene is almal uitgedruk en betrokke in die mitokondriese wanfunsionerings-weë. Hierdie resultate dui dat die afwesigheid van parkin mitokondriese afwykings tot gevolg het wat kan lei tot die afsterwing van selle. Dit dra ook by tot die vorming van ‘n beter-verstaande siekte-model vir PS: Mutasies in parkin (wat lei tot die afwesigheid van parkin) kan dus moontlik lei tot die af-regulasie van gene geassosieerd met die elektron-vervoer ketting komplekse in die mitokondria. Dit lei tot gebrekkige oksidatiewe fosforilering en veroorsaak ‘n toename in die vorming van ROS, wat dan ‘n toename in oksidatiewe stres binne in die sel tot gevolg het. Uiteindelik lei dit dus tot die beskadiging van die mitokondria wat gepaard gaan met fragmentering van die mitokondriese netwerk. Beskadigde mitokondrias word geetiketeer vir afbraking. Hierdie etiketering aktiveer omringende autophagosome wat die beskadigde mitokondrias dan verwyder deur middel van ‘n verswelgende proses genaamd mitophagy. Dit veroorsaak die aktivering van ‘n aantal gekorreleerde sellulêre prosesse wat lei tot apoptose (afsterwing van die sel). Hierdie studie dra by tot die verklaring van die spesifieke effek wat parkin mutasies het op die funksionering van die mitokondria. Resultate hier lê ook die grondslag vir toekomstige studies met die doel tot die ontwikkeling van terapeutiese strategeë en biochemiese merkers wat kan bydrae tot die genesing van beide pasiënte met PS, asook pasiënte met ander neurodegeneratiewe afwykings.
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Kubaski, Francyne. "Padronização de um protocolo para identificação de mutações no gene da GALNS em pacientes com MPS IVA através das técnicas de PCR-ARMS (Amplification Refractory Mutation System) e sequenciamento." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/67647.
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Introdução: Mucopolissacaridose IVA ou Síndrome de Morquio A é uma doença autossômica recessiva causada pela deficiência da enzima lisossomal Nacetilgalactosamina- 6-sulfatase (GALNS), que resulta no acúmulo lisossomal dos glicosaminoglicanos: Queratan sulfato e Condroitin-6-sulfato nos tecidos causando as manifestações clínicas. Os fenótipos variam da forma clássica à forma atenuada, ambas sem comprometimento cognitivo. A prevalência de MPS IVA varia de 1/76.000 a 1/640.000 nascidos vivos. Objetivos: Analisar e caracterizar o genótipo de pacientes brasileiros com MPS IVA através de estudos de mutações no gene da GALNS, possibilitando a estimativa de frequência de mutações recorrentes e o estabelecimento um protocolo de rotina para triagem dessas mutações. Métodos: Análise molecular do gene da GALNS foi realizada em 26 pacientes brasileiros inicialmente através de PCR-ARMS para detecção de seis mutações recorrentes (p.G116S/ p.G139S/ p.L307P/ p.N164T/ p.R386C e p.S341R) seguidas pela amplificação de regiões codificantes por PCR e sequenciamento. Resultados: Essas mutações foram encontradas em 61,5% da nossa amostra, com uma frequência alélica de 55,8%. Destas, a mutação mais frequente foi p.S341R (26,9%), seguida de p.R386C (21,1%) e p.G116S (7,7%). As mutações p.N164T, p.G139S, p.L307P não foram encontradas em nossa amostra. Além destas, foi encontrada por sequenciamento do éxon 5 uma mutação nova p.C165Y. Conclusão: O protocolo usado para detecção de mutações comuns mostrou-se adequado como um screening inicial de mutações no gene da GALNS, identificando mutações em 61,5% dos pacientes e permitiu a caracterização de 55,8% dos alelos. A mutação p.S341R foi encontrada apenas em pacientes do Nordeste. A identificação de indivíduos heterozigotos nessas famílias será importante para aconselhamento genético e para estimar a prevalência da doença nessa região. Estudos adicionais para identificação da origem dessa mutação, incluindo análises de segregação e haplótipo estão em andamento, e serão avaliadas em conjunto com dados epidemiológicos.Background: Mucopolysaccharidosis IVA or Morquio A syndrome, is an autosomal recessive disorder caused by deficiency of lysosomal enzyme Nacetylgalactosamine- 6-sulfatase (GALNS), which results in lysosomal storage of glycosaminoglycans: Keratan sulfate and Chondroitin-6-sulfate in tissues causing clinical manifestations. The phenotypes vary from the classical to attenuated form, both without cognitive impairment. The prevalence of MPS IVA ranges from 1/76.000 to 1/640.000 live births. Objective: To analyze and characterize the genotype of Brazilian patients with MPS IVA, through molecular study of mutations in the GALNS gene, enabling the estimative of frequency of recurrent mutations and the establishment of a protocol for routine screening of these mutations. Methods: Molecular analysis of GALNS gene was performed in 26 Brazilian patients initially by ARMS-PCR to detect six recurrent mutations (p.G116S/ p.G139S/ p.L307P/ p.N164T/ p.R386C and p.S341R) followed by amplification of coding regions by PCR and sequencing. Results: These mutations were found in 61.5% of our sample, which were present in 55.8% of the alleles. The most frequent mutation was p.RS341R (26.9%), followed by p.R386C (21.1%) and p.G116S (7.7%). Mutations p.N164T, p.G139S, p.L307P were not found in our sample. A novel mutation p.C165Y was found after sequencing of exon 5. Conclusion: The protocol used for detection of common mutations was shown to be adequate for a first screening of mutations at the GALNS gene, once it identified the genotype in 61.5% of patients and allowed the characterization of 55.8% of alleles. The p.S341R was found only in patients from the Northeast. The identification of heterozygous individuals within these families will be important for genetic counseling and for estimating the disease prevalence in this region. Further studies to identify the origin of this mutation, including haplotype and segregation analyses are in progress, and will be evaluated in conjunction with epidemiological data.
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Tannouri, Rachelle El. "Établissement d’une cohorte de patientes ayant consulté à l’Institut de Cancérologie de Lorraine et porteuses de la mutation BRCA1-3600del11 : étude descriptive des caractéristiques cliniques et anatomo-pathologiques des cancers du sein et de l’ovaire dans cette cohorte : mise en évidence d’un phénomène d’anticipation génétique dans 38 paires mères-filles atteintes de cancer du sein ou de l’ovaire." Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0072/document.
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Contexte: La grande majorité des mutations délétères identifiées sur le gène BRCA1 sont des mutations « privées ». Cependant, certaines d’entre elles proviennent d’un ancêtre commun, à l’origine d’un effet fondateur. Ainsi, la mutation BRCA1-3600del11 (c.3481_3491del11, p.Glu1161Phefs*3) est localisée en France pour 82% des familles porteuses et 85% d’entre elles sont originaires du quart Nord-Est. En 2006, cette mutation représentait respectivement 51,5% et 42,0% de toutes les mutations du gène BRCA1 identifiées dans les familles lorraines et alsaciennes atteintes d’un cancer du sein et/ou de l’ovaire. En 2004, parmi les 27 cas-index ayant consulté en Alsace et présentant une mutation de BRCA1, 37% sont porteurs de cette mutation, tous issus de familles originaires des Vosges, suggérant l’existence d’un effet fondateur. L’identification d’un haplotype commun est venue confirmer l’existence de cette hypothèse. Une équipe alsacienne a mentionné dans deux publications en 2000 et 2004 sur la mise en évidence de la mutation 3600del11 que les caractéristiques des cancers associés à cette mutation, ne plaidaient pas en faveur d’une relation génotype-phénotype. Or, les caractéristiques anatomo-pathologiques des cancers associés à cette mutation n’ont pas été abordées par ces deux publications. Nous nous sommes alors posés la question de caractéristiques anatomo-pathologiques particulières des cancers du sein et des cancers de l’ovaire diagnostiqués chez les femmes porteuses de cette mutation dans notre région. Nous nous sommes également posés la question de l’existence d’un phénomène d’anticipation génétique dans ces familles. L’anticipation génétique est la survenue plus précoce d’une pathologie et/ou l’aggravation de ses signes cliniques lors de la transmission d’une mutation d’une génération à la suivante au sein d’une même famille. Très peu d’études ont cherché à mettre en évidence ce phénomène d’anticipation dans des cohortes issues de familles de syndrome sein-ovaire associées à une mutation de BRCA1 ou BRCA2. Les études publiées présentaient des biais de sélection du fait de l’inclusion de patients non testés dans leur analyse. Les études publiées sur des cohortes issues de familles présentant une mutation sur le gène BRCA1/2 suggéraient que le dépistage ciblé et l’excès de surveillance pourraient avoir une influence sur l’âge au diagnostic d’un cancer du sein chez les jeunes femmes incluses.Les améliorations majeures au niveau de la mammographie et du traitement du cancer du sein, de même que le programme de dépistage organisé pour les femmes de 50 ans et plus sont apparues en France, après 1980. A notre connaissance, à ce jour, aucune étude n’a été réalisée en France visant à identifier un phénomène d’anticipation génétique dans les familles associées à une mutation sur BRCA1ou BRCA2 et à analyser ce phénomène.Objectif: Notre premier objectif est de constituer une première cohorte lorraine de patientes porteuses de la mutation 3600del11 et d’analyser les caractéristiques anatomo-pathologiques des cancers du sein et de l’ovaire liés à cette mutation. Notre deuxième objectif rechercher l’existence d’une anticipation génétique dans des familles présentant la mutation fondatrice BRCA1-3600del11.Patientes: Quatre cent quatre patientes sont porteuses d’une mutation BRCA1 à l’Institut de Cancérologie de Lorraine (ICL) sur la période s’étendant de 1994 à 2012, parmi elles, nous avons identifié les patientes porteuses de la mutation BRCA1-3600del11. Nous avons identifié à l’Institut de Cancérologie de Lorraine, 38 paires mères-filles atteintes d’un cancer du sein ou de l’ovaire issues de 37 familles présentant le syndrome sein-ovaire associé à cette mutation dont 25 paires mères-filles atteintes d’un cancer du sein et 13 paires mères-filles atteintes d’un cancer de l’ovaire [...]Introduction: Over 1000 alterations in the BRCA1 gene have been documented. Most of these are frameshifts and ~10% are missense mutations that generate stop codons leading to a truncated and therefore inactive BRCA1 protein. In the French population, prevalence of BRCA1 mutations has been reported in few studies; In a preliminary study of 14 breast and/or ovarian cancer families, a frequent BRCA1 mutation was detected in five unrelated families; the c.3481_3491del11 mutation (BIC: 3600del11), an 11 base-pair deletion in exon 11 leading to a premature stop codon at 1165. In a second study carried out in 2004 involving 27 index cases, the c.3481_3491del11 mutation accounted for 37%. The haplotype analysis of the families carrying the mutation c.3481_3491del11, all originating from Alsace-Lorraine (North-East of France), revealed the presence of a common allele, indicating a founder effect. Purpose: To an attempt to better define the clinical and pathologic characteristics of breast and ovarian cancer related with the 3600del11 BRCA1 mutation, we report our experience with breast and ovarian cancer patients carrying the 3600del11 mutation at the Lorraine Oncology Institute in France. The aim of the current analysis is also to evaluate any differences of breast or ovarian cancer age at diagnosis between mothers and daughters carrying the c.3481_3491del11 mutation in the BRCA1 gene.Patients: Within the population who were referred between 1994 and 2012 to our oncogenetic clinic at the Lorraine oncology institute and who underwent genetic testing for BRCA1 and BRCA2, we identified 404 women carrying a BRCA1 mutation. Interestingly, 45% (180 of 404) of women with detected BRCA1 mutation had the germline 3600del11 mutation. These women were members of 89 different families with breast and or ovarian cancer cases. A study cohort of 38 women carrying the c.3481_3491del11 mutation and affected by first breast or ovarian cancer who reported a first breast or ovarian cancer in their mother carrying the c.3481_3491del11 mutation, was identified in 37 different families including members with breast and/or ovarian cancer at the Oncology Institute of Lorraine. Twelve mothers underwent genetic testing. Twenty five pairs of the 38 mothers-daughters pairs with c.3481_3491del11 mutation were affected by breast cancer and 13 pairs by ovarian cancer.Methods: Clinical and genetic data were collected from medical files and family pedigrees. Analyses were conducted for each cancer type. We investigated an early breast cancer detection effect due to early screening programs and also an increased breast tumor aggression. Since major improvements in breast cancer clinical management and imaging techniques appeared after 1980, we compared the age at breast cancer diagnosis and the age at death in mothers and daughters before and after 1980, first, in the group of women including mothers and daughters taken together and then in mothers and daughters separately. Genetic data were retrieved from familial files and clinical and pathological data from medical files. Descriptive statistics for the study population were calculated using the SPSS software (version 20.0). Results: Ninety one patients (71, 7%) were affected by first breast cancer and 31 (24,4%) by ovarian cancer. Breast tumors were identified in 37.4% of cases aged <40 years. Estrogen receptor status and progesterone receptor status were reported to 67 patients. Hormonal receptors status was positive in 31.4% of breast tumors. A triple-negative subtype was found in 21 cases, which accounts for 65.6% of the 32 patients with 3600del11 mutation for whom HER2 status was available. Ovarian tumors of the serous type, which constitute about 71 percent of all epithelial ovarian carcinomas, predominate among patients with 3600del11 mutation. Eighty six per cent of carriers were diagnosed at advanced stages III/IV [...]
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Costa, Thaís Virgínia Moura Machado. "Análise da presença de mutação no gene TARDBP em pacientes com degeneração lobar frontotemporal e implementação de metodologia para determinação dos polimorfismos do gene APOE em pacientes com Doença de Alzheimer em São Paulo - SP." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/5/5138/tde-02102012-084400/.
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Atualmente, as demências tornam-se mais prevalentes e constituem-se como um importante problema de saúde pública mundial. A Degeneração Lobar Frontotemporal (DLFT) e a Doença de Alzheimer (DA) são as de maior incidência. A investigação dos fatores de risco para as demências degenerativas inscreve-se entre os temas mais relevantes das neurociências e a avaliação dos fatores de risco de natureza genética tem produzido contribuições importantes. Na DLFT, mutações no gene TARDBP, codificador da proteína nuclear TDP-43, estão entre as ocorrências genéticas mais descritas, enquanto que para a DA, o alelo 4 do gene da apolipoproteína E (APOE) é o principal fator de risco. Pacientes com diagnóstico clínico de DLFT (n=47) e de DA provável (n=30) recebidos do ambulatório do Grupo de Neurologia Cognitiva e do Comportamento (GNCC) da Clínica Neurológica do HC-FMUSP foram convidados a participar do estudo. Amostras de sangue foram coletadas para a realização da extração de DNA linfocitário. Os éxons de 1-6 do gene TARDBP foram amplificados por PCR e seus produtos foram sequenciados em sequenciador automático. Os polimorfismos do gene APOE foram determinados através da técnica de PCR em tempo real. A análise do gene da TDP-43 em pacientes com DLFT mostrou a presença de uma mutação na região do éxon 6 do TARDBP (g.14935A>G) em um paciente do sexo masculino, com idade de 54 anos e diagnóstico de demência semântica. Na genotipagem dos pacientes de DA, foi observado que a metodologia utilizada, através de PCR em tempo real mostrou-se eficiente em detectar os polimorfismos do gene APOE, fornecendo resultados compatíveis quando comparados aos demais estudos brasileiros publicados anteriormenteBrazil is one of the developing countries that are undergoing a process of demographic transition in which the elderly represents a significant proportion of the total population. Neurodegenerative illnesses most commonly appear at such ages. Frontotemporal lobar degeneration (FTLD) and Alzheimers disease (AD) are the most frequent causes for dementia. The investigation of risk factors for degenerative dementia is a relevant subject of neurosciences and the evaluation of the nature of genetic risk factors has produced the most important contributions. Mutations in TARDBP gene, the encoder of the TDP-43 nuclear protein, appear as the most frequent genetic occurrences for FTLD, whereas, in DA, the 4 allele of the apolipoprotein E (APOE) is the major genetic risk factor. Patients with clinical diagnosis of FTLD types of families and sporadic (n=47) and probable AD (n=30) from the ambulatory of Cognitive Neurology Group and Behavior (CNGB) of Neurological Clinic of HC-FMUSP were invited to participate in this study. Blood samples were collected for lymphocytic DNA extraction. The APOE gene polymorphisms are being determined through the real time PCR technique. The 1-6 exons of TARDBP gene were amplified by PCR and their products were sequenced in automated sequencer. The TDP-43 gene analysis in patients with FTLD showed the presence of one mutation in the region of exon 6 TARDBP gene in a male patient of 54 years old, with diagnoses of semantic dementia. Regarding DA patients genotyping, the real time methodology has been shown as an efficient approach to detect APOE polymorphisms, presenting data similar to those observed in other Brazilian studies
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Quiles, Vidal Francisco de Asís. "Síndrome de cáncer de mama y ovario hereditario: Estudio in vitro de variantes BRCA1 y BRCA2 de significado biológico desconocido y búsqueda de nuevos genes responsables de este síndrome." Doctoral thesis, Universitat de Barcelona, 2016. http://hdl.handle.net/10803/385989.
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ANTECEDENTES: Entre un 20-25% de pacientes con cáncer de mama y ovario muestran historia familiar de dicha enfermedad. Una porción de estos casos son debidos a mutaciones germinales en genes de predisposición conocidos y se engloban dentro del síndrome de cáncer de mama y ovario hereditario (SCMOH). Mutaciones en los genes BRCA1/2, genes de alta penetrancia para este síndrome, explican alrededor de un 20% de los casos familiares. El estudio mutacional de estos genes identifica entre un 2-15 de variantes cuyo significado biológico es desconocido (VSD), dependiendo de la población analizada y la casuística del laboratorio que las reporta. Debido a la imposibilidad de determinar el riesgo asociado a una VSD, éstas no pueden ser utilizadas como valor predictivo en el diagnóstico genético y dificultan el seguimiento clínico del portador. Por ello, la clasificación de estas variantes en patogénicas o neutras es de gran importancia desde del punto de vista del consejo genético. Además de lo mutaciones en los genes BRCA1/2, otras mutaciones de alta, moderada o baja penetrancia se han identificado en otros genes y con ellas se ha podido explicar una pequeña porción de los casos restantes del SCMOH. Muchos de estos genes han están involucrados en la vía de reparación de DNA de Anemia de Fanconi (FA)/BRCA, o son interactores de BRCA1/2. Si bien, más de un 50% de los casos familiares permanecen sin causa genética conocida. Estos casos son comúnmente conocidos como casos BRCAX. En este contexto, el uso de las nuevas técnicas de secuenciación de exomas ha demostrado ser una buena estrategia para la identificación de nuevos genes de predisposición al SCMOH.
OBJETIVO: El objetivo global de esta tesis doctoral es mejorar el diagnóstico y el consejo genético de los pacientes con SCMOH mediante la clasificación de VSD en los genes BRCA1/2 y la búsqueda de nuevos genes de predisposición a este síndrome.
RESULTADOS: Cuarenta VSD en BRCA1/2 fueron analizadas siguiendo diferentes aproximaciones experimentales. Veintiocho de ellas fueran analizadas a nivel transcripcional y 6 (4 en BRCA1 y 2 en BRCA2) fueron clasificadas como probablemente patogénicas en base a su efecto en el correcto splicing de estos genes. Otras 7 variantes, localizadas en la región C-terminal de BRCA1, fueron analizadas mediante el ensayo de actividad transcripcional. Tres de estas variantes pudieron ser clasificadas como probablemente patogénicas. Posteriormente, una de estas variantes, G1770V fué identificada por nuestro grupo como la primera mutación fundadora de origen Marroquí. Las cinco restante, situadas en BRCA2, fueron analizadas mediante el ensayo funcional basado en células embrionarias de ratón. Todas ellas mostraron un efecto hipomórfico y fueron asociadas a un riesgo bajo/moderado a sufrir cáncer d mama y/o ovario. En cuanto a la búsqueda de nuevos genes de predisposición al SCMOH se utilizaron dos aproximaciones para su identificación. Por un lado, se secuenciaron dos genes nuevos genes de la vía de FA/BRCA, los genes ERCC4 y SLX4, en un set de pacientes BRCAX. Este estudio identificó varias variantes missense nuevas en cada gen. Varias de ellas fueron clasificadas como potencialmente deletéreas por varios programas de predicción in silico. No obstante, la validación funcional de estas variantes es necesaria para elucidar su asociación con el SCMOH. Como segunda aproximación, se secuenció el exoma de varios pacientes pertenecientes a familias BRCAX con un aparente patrón de herencia autosómico dominante. Como resultado, se identificaron 20 genes potencialmente candidatos para ser genes de predisposición al SCMOH. Entre ellos, POLE destaca como firme candidato.
CONCLUSIÓN: Este trabajo, en su conjunto, contribuye a la mejora del diagnóstico y consejo genético mediantes la identificación de nuevas variantes de predisposición en al SMCOH en los genes BRCA1/2 y la identificación de nuevos genes candidatos al SCMOH.BACKGROUND: Breast cancer is the most common cáncer diagnosed among women. Between 20-25% of breast cancer cases present familial history of the disease. Around 50% of familial breast cancer is due to germline mutations in predisposing genes and are included in the Hereditary Breast and Ovarian Cancer Syndrome (HBOCS) cases. The other 50% of familial cases remains genetically unsolved which indicates the need of identifing new predisposing genes for this syndrome. The most prevalent predisposing genes for this syndrome, BRCA1/2, account for least than the 20% of the familias cases. Genetic testing of this genes identifies between 2-15% of variants of unknown significance (VUS). This variants difficult the clinical monitoring of carriers, thus the need of classyfy them as pathogenic or neutral variant is paramount from the genetic counseling point of view. OBJECTIVE: The objective of this thesis is to improve the genetic diagnosis and gentic counseling os HBOCS patients by the classification of VUS in BRCA1/2 and the identification of new predisposing genes of this syndrome. RESULTADOS: Forty VUS in BRCA1/2 were analyzed using different experimental approaches (RNA analysis or funtional assays). Fourteen of them could be associated with the HBOCS. One of this variants, G1770V was later identified as the first founder mutation of Moroccan population. In the searching of new predisposing genes of the HBOCS we used two approaches. On one hand, we sequenced two new fanconi anemia genes, ERCC4 y SLX4, in 94 BRCAX families. This study didn’t find any clear loss of function variant in these genes, so their contribution to the HBOCS couldn’t be determined. On the other hand, we sequenced the whole exome of several patients from 12 independet BRCAX i families with an apparent autosomial dominant pattern of inheritance. AS a result of this study we identified 20 potential candidate HBOCS predisposing genes. Between them, POLE highlights as strong candidate. CONCLUSION: Overall, this work, by the identification of new predisposing variants in BRCA1/2 and the identification of new susceptybility candidates genes of the HBOCS, contributes to the improvement of the genetic diagnostic and counseling of HBOCS patients
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Obermaier, Carolin Dominique [Verfasser], and Rejko [Akademischer Betreuer] Krüger. "Identification of the underlying mechanism of the c.192G>C mutation in the DJ-1 gene and functional characterisation in patient-based cellular models of Parkinson’s disease ex vivo / Carolin Dominique Obermaier ; Betreuer: Rejko Krüger." Tübingen : Universitätsbibliothek Tübingen, 2015. http://d-nb.info/116523498X/34.
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Obermaier, Carolin [Verfasser], and Rejko [Akademischer Betreuer] Krüger. "Identification of the underlying mechanism of the c.192G>C mutation in the DJ-1 gene and functional characterisation in patient-based cellular models of Parkinson’s disease ex vivo / Carolin Dominique Obermaier ; Betreuer: Rejko Krüger." Tübingen : Universitätsbibliothek Tübingen, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:21-dspace-649120.
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Chamcheu, Jean Christopher. "Disease-causing Keratin Mutations and Cytoskeletal Dysfunction in Human Skin : In vitro Models and new Pharmacologic Strategies for Treating Epidermolytic Genodermatoses." Doctoral thesis, Uppsala universitet, Institutionen för medicinska vetenskaper, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-123071.
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Epidermolysis bullosa simplex (EBS) and epidermolytic ichthyosis (EI) are rare skin fragility diseases characterized by intra-epidermal blistering due to autosomal dominant-negative mutations in basal (KRT5 or KRT14) and suprabasal (KRT1 or KRT10) keratin genes, respectively. Despite vast knowledge in the disease pathogenesis, the pathomechanisms are not fully understood, and no effective remedies exist. The purpose of this work was to search for keratin gene mutations in EBS patients, to develop in vitro models for studying EBS and EI, and to investigate novel pharmacological approaches for both diseases. We identified both novel and recurrent KRT5 mutations in all studied EBS patients but one which did not show any pathogenic keratin mutations. Using cultured primary keratinocytes from EBS patients, we reproduced a correlation between clinical severity and cytoskeletal instability in vitro. Immortalized keratinocyte cell lines were established from three EBS and three EI patients with different phenotypes using HPV16-E6E7. Only cell lines derived from severely affected patients exhibited spontaneous keratin aggregates under normal culture conditions. However, heat stress significantly induced keratin aggregates in all patient cell lines. This effect was more dramatic in cells from patients with a severe phenotype. In organotypic cultures, the immortalized cells were able to differentiate and form a multilayered epidermis reminiscent of those observed in vivo. Addition of two molecular chaperones, trimethylamine N-oxide dihydrate (TMAO) and sodium 4-phenylbutyrate (4-PBA), reduced the keratin aggregates in both stressed and unstressed EBS and EI keratinocytes, respectively. The mechanism of action of TMAO and 4-PBA was shown to involve the endogenous chaperone system (Heat shock proteins e.g. Hsp70). Besides, MAPK signaling pathways also seemed to be incriminated in the pathogenesis of EBS. Furthermore, depending on which type of keratin is mutated, 4-PBA up-regulated Hsp70 and KRT4 (possibly compensating for mutated KRT1/5), and down-regulated KRT1 and KRT10, which could further assist in protecting EBS and EI cells against stress. In conclusion, novel and recurrent pathogenic keratin mutations have been identified in EBS. Immortalized EBS and EI cell lines that functionally reflect the disease phenotype were established. Two pharmacologic agents, TMAO and 4-PBA, were shown to be promising candidates as novel treatment of heritable keratinopathies in this in vitro model.
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Giacomazzi, Juliana. "Prevalência da mutação germinativa TP53 p.R337H em indivíduos com tumores do espectro da Síndrome de Li-Fraumeni." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/115624.
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Introdução: Estudos prévios têm indicado que uma mutação germinativa específica no gene TP53, p.R337H está associada a efeito fundador no Brasil e é muito frequente entre certos tipos tumorais. Objetivos e Metodologia: O objetivo deste estudo foi verificar a prevalência da mutação germinativa TP53 p.R337H em indivíduos com tumores do espectro da Síndrome de Li-Fraumeni (SLF) e/ou Li- Fraumeni-Like (LFL) divididos em diferentes grupos: (1) mulheres com câncer de mama (CM) subdivididas em 2 subgrupos: (a) com critérios para síndromes de predisposição hereditária ao câncer, exceto para SLF/LFL; (b) não selecionadas para história familiar (HF), diagnosticadas antes dos 45 e após 55 anos de idade em diferentes regiões do país; (2) mulheres com tumores phyllodes da mama, diagnosticadas em diferentes idades e não selecionadas para HF da doença nas regiões Sul e Sudeste; (3) crianças com tumores do espectro da SLF/LFL, não selecionadas para HF e atendidas em um Serviço de Oncologia Pediátrica do Sul do país. Adicionalmente, foi investigada a presença do haplótipo fundador brasileiro nos portadores da mutação TP53 p.R337H. No grupo 3 foi ainda avaliada a prevalência de critérios para SLF/LFL e a presença de outras mutações germinativas no gene TP53. Resultados: No subgrupo 1A foram incluídas 59 mulheres das quais 2 eram portadoras da mutação TP53 p.R337H, ambas com HF exclusivamente para a Síndrome de Prediposição Hereditária ao Câncer de Mama e Ovário no momento do recrutamento. No subrupo 1B foram incluídas 815 mulheres (403 com CM N45 anos e 412 casos com CM O 55 anos) provenientes de 25 diferentes Estados do Brasil. A mutação foi encontrada em 8,6% (70/815) dos casos, sendo observada diferença significativa na frequência de acordo com o centro de recrutamento. Em todos centros, a mutação foi mais frequente em mulheres com CM antes dos 45 anos. Análise do tecido tumoral de 15 portadoras evidenciou perda de heterozigosidade (LOH) em apenas 2 casos. Os tumores de mama de mulheres portadoras apresentavam mais frequentemente alguma expressão de HER2 (1+, 2+ ou 3+). No grupo 2, foram incluídas 148 mulheres com tumores phyllodes da mama e 8 (5,4%) apresentaram a mutação, sendo mais frequente entre os tumores malignos (3/13; 23%) quando comparada aos benignos (5/128; 3.4%). No grupo 3 foram incluídas 292 crianças diagnosticadas com tumores do espectro da SLF/LFL, das quais 25,3% tinham critérios para SLF/LFL. O sequenciamento completo e pesquisa de rearranjos gênicos de TP53 em 48 das crianças com câncer e critérios estritos para LFL evidenciou apenas um caso com uma mutação clássica – p.G245S. A mutação TP53 p.R337H foi identificada somente entre os casos com carcinoma adrenocortical (9/11; 81,8%) e de plexo coróide (2/2; 100%), correspondendo a 3,8% da amostra total. Um dos casos de carcinoma adrenocortical apresentou a mutação TP53 p.R337H em homozigose. Todos tumores de portadores analisados (n=8) apresentaram LOH. Conclusão: Conclui-se que a mutação germinativa TP53 p.R337H ocorre em mulheres brasileiras com CM em diferentes faixas etárias, independente da HF de câncer. Em mulheres com fenótipo de CM hereditário sem critérios para SLF/LFL a mesma também foi observada. A freqüência da mutação foi variável de acordo com o centro de recrutamento, sendo identificada em todas as regiões brasileiras. Os tumores de mama de pacientes portadoras da mutação têm um perfil peculiar, com baixa frequência de LOH e presença de alguma expressão de HER2. A mutação p.R337H ocorre em tumores phyllodes da mama benignos e especialmente malignos, confirmando a hipótese prévia de associação de mutações germinativas em TP53 com estes tumores. Entre crianças com tumores do espectro SLF/LFL de um centro de referência no Sul do Brasil, um percentual significativo tem indicação para teste de mutações em TP53, no entanto, na maioria destes casos não se identifica mutação germinativa no gene. A mutação TP53 p.R337H ocorre em elevada frequência na linhagem germinativa de crianças com carcinomas adrenocortical e de plexo coróide, como descrito em outras regiões brasileiras. Por fim, o haplótipo fundador foi identificado em todos portadores da mutação analisados, incluindo 3 casos das regiões Norte, Nordeste e Centro-Oeste do país. A mutação TP53 p.R337H está associada a efeito fundador no Brasil e tem importante contribuição na gênese de tumores de mama, bem como de carcinomas adrenocortical e de plexo coróide no Sul do país.Introduction: Previous studies have reported that a specific germline mutation in TP53, p.R337H, is associated with a founder effect and is common among certain tumor types. Objectives and Methodology: Assess the prevalence of TP53 p.R337H germline mutation in subjects with tumors of the Li-Fraumeni/ Li-Fraumeni- Like (LFS/LFL) spectrum divided into different groups: (1) women diagnosed with breast cancer (BC) subdivided into 2 subgroups: (a) with criteria for hereditary predisposition syndromes, except for LFS/LFL (b) unselected for family history (FH) diagnosed at or before 45 years and at or after 55 years recruited in different regions of the country; (2) women with phyllodes breast tumors, diagnosed at different ages and not selected for FH of the disease from the South and Southeast of Brazil; (3) children with tumors of the LFS/LFL spectrum and not selected for FH of the disease from a Pediatric Oncology Service in South Brazil. In addition, presence of the founder Brazilian haplotype in mutation carriers identified in groups 1, 2 and 3 was assessed. Finally, in group 3, prevalence of LFS/LFL criteria and presence of other germline TP53 mutations were investigated. Results: In subgroup 1A, 59 women were included and two of these were mutation carriers, both had a FH consistent only with Hereditary Breast and Ovarian Cancer Syndrome at recruitment. In subgroup 1B, 815 women (403 cases diagnosed N 45 years and 412 cases, O 55 years) were included from 25 different Brazilian States. The TP53 p.R377H mutation was found in 8.6% (70/815), and significant differences in mutation frequency were observed according to recruitment center. In all centers the mutation was more frequent in women diagnosed with BC at or before 45 years. Analysis of tumor tissue of 15 carriers showed loss of heterozygosity (LOH) in only 2 cases. Breast tumors of carriers showed, more frequently, some expression of HER2. In group 2 were included 148 women with breast phyllodes tumors and 8 (5.4%) were p.R337H carriers, which was most common among malignant phyllodes tumors (3/13, 23%) when compared to benign (5/128, 3.4%). In the group 3, 292 children with tumors of the LFS/LFL spectrum were included, and 25.3% of these had criteria for LFS/LFL. TP53 gene sequencing and rearrangement testing in 48 children with the more strict criteria for the syndrome identified a classic germline mutation, p.G245S, in only one proband. The TP53 p.R337H mutation was identified only among patients with adrenocortical carcinoma (9/11, 81.8%) and choroid plexus carcinoma (2/2, 100%), corresponding to 3.8% of the total sample. One of the patients with adrenocortical carcinoma was homozygous mutant. All tumors of TP53 p.R37H carriers analyzed (n=8) showed LOH. Conclusion: We conclude that the TP53 p.R337H germline mutation occurs in Brazilian women with BC in different age groups, regardless of BC FH. In women with hereditary BC without criteria for LFS/LFL criteria, it was also observed. The mutation frequency varied according to the recruiting center and carriers were identified in all Brazilian regions. Breast tumors of carriers have a peculiar profile, with low frequency of LOH and the presence of HER2 expression. The mutation was present, also, in benign and especially malignant phyllodes tumors, confirming the previous hypothesis of an association between germline mutations in the TP53 gene and these specific tumors. Among children with tumors of the LFS/LFL spectrum from a Oncopediatrics referral center in South Brazil, a significant percentage fulfills criteria for TP53 mutation testing, however, in most of these cases, no germline mutations were identified. The TP53 p.R337H mutation occurs in high frequency in the germline of children with adrenocortical and choroid plexus carcinomas, as described in other Brazilian regions. Finally the founder haplotype was identified in all mutation carriers analyzed, including 3 cases from the Northern, Northeastern and Midwestern Brazilian regions. The TP53 p.R337H mutation is associated with a founder effect in Brazil and has an important contribution in the genesis of breast tumors in the country, as well as adrenocortical and choroid plexus carcinomas in the Southern region of the country.
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Fonseca, Jonathan Mackowiak da. "O crescimento cístico renal é o principal determinante para o desenvolvimento de hipertensão e déficit de concentração em camundongos com deficiência do gene Pkd1." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/5/5160/tde-22012013-170944/.
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O desenvolvimento de hipertensão arterial (HAS) ocorre dez anos mais cedo em pacientes com doença renal policística autossômica dominante (DRPAD) comparados à população geral, estando presente em ~60% dos indivíduos afetados antes da perda de função renal. Déficit de concentração renal também se constitui em um achado precoce nesses pacientes. Atualmente se propõe que o sistema renina angiotensina desempenhe um papel central na HAS relacionada à DRPAD, enquanto diferentes explicações têm sido levantadas para justificar o defeito de concentração. Realizamos um cruzamento envolvendo um alelo floxed de Pkd1 com uma linhagem com expressão de nestina-Cre, de modo a gerar camundongos machos císticos viáveis (Pkd1cond/cond:Balcre, CI) com TFG preservada. Estes animais foram avaliados sistematicamente para uma série de parâmetros renais funcionais, morfológicos, celulares e moleculares. Análises paralelas foram conduzidas em camundongos haploinsuficientes para Pkd1 (Pkd1+/-, HT), os quais não desenvolvem cistos renais visíveis. Camundongos CI mostraram-se significantemente hipertensos na idade de 10-13 semanas, um fenótipo não observado em controles não císticos (Pkd1cond/cond, NC) e em animais haploinsuficientes para Pkd1. As frações de excreção de Na+ e K+ mostraram-se reduzidas e a concentração sérica de uréia discretamente elevada em camundongos CI, sugerindo reabsorção tubular de solutos aumentada. A expressão gênica de angiotensinogênio foi significantemente maior em rins CI que NC, enquanto análises imunoistoquímicas revelaram expressão da enzima conversora de angiotensina e do receptor AT1 em epitélio cístico renal. A excreção urinária de NO2 também se mostrou diminuída em camundongos CI, acompanhando-se de taxas aumentadas de proliferação celular e apoptose renais. A osmolalidade urinária máxima foi mais baixa em animais CI, um déficit não encontrado nos controles HT e NC. Interessantemente, uma tendência de níveis plasmáticos mais elevados de vasopressina foi observada em camundongos CI. Tomados em conjunto, esses resultados apoiam a hipótese de que a formação e o crescimento de cistos desempenham um papel importante no desenvolvimento de HAS na DRPAD e de que a ativação do sistema renina-angiotensina intrarrenal constitui-se em um mecanismo fundamental nesse processo. Nossos achados também sugerem fortemente que a expansão cística seja essencial para o desenvolvimento do déficit de concentração renal nessa doença, e são consistentes com a existência de áreas focais de compressão vascular e perfusão diminuída em rins com DRPAD.Hypertension (SAH) develops ten years earlier in autosomal dominant polycystic kidney disease (ADPKD) patients compared with the general population, being present in ~60% of affected individuals before the loss of renal function. Renal concentrating deficit is also an early finding in these patients. It has been proposed that the renin-angiotensin system plays a central role in ADPKD-related SAH, while different explanations have been raised to justify the concentrating impairment. We bred a floxed allele of Pkd1 with a nestin Cre expressing line to generate viable, adult male cystic mice (Pkd1cond/cond:Balcre, CY) with preserved GFR. These animals were systematically evaluated for a series of renal functional, morphological, cellular and molecular parameters. Parallel analyses were carried out in Pkd1-haploinsuficient mice (Pkd1+/-, HT), which do not develop visible renal cysts. CY mice were significantly hypertensive by 10-13 weeks of age, a phenotype not seen in non-cystic controls (Pkd1cond/cond, NC) and Pkd1-haploinsufficient animals. The fractional excretion of Na+ and K+ were reduced and SUN slightly elevated in the CY mice, suggesting increased tubular solute reabsorption. Angiotensinogen gene expression was significantly higher in CY than NC kidneys, whereas immunohistochemical analyses revealed angiotensin-converting enzyme and AT1 receptor expression in renal cyst epithelia. Urine excretion of NO2 was also diminished in CY mice, along with increased rates of renal cell proliferation and apoptosis. Maximum urine osmolality was decreased in CY animals, a deficit not found in HT and NC controls. Interestingly, a trend toward increased serum vasopressin levels was observed in the CY mice. Taken together these results support the hypothesis that cyst formation and growth play an important role in the development of SAH in ADPKD and that activation of the intrarenal reninangiotensin system is a fundamental mechanism in this process. Our findings also strongly suggest that renal cyst expansion is essential for the development of renal concentrating deficit in this disease, and are consistent with the existence of focal areas of vascular compression and reduced perfusion in ADPKD kidneys.
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Mano, Emy Tiyo. "Identificação de genes de Burkholderia sp. associados ao controle biológico de Pectobacterium carotovora." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/87/87131/tde-23032011-143651/.
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A bacteria Pectobacterium carotovora causa danos a diferentes hospedeiros por meio da produção de enzimas pectinolíticas que degradam o pectato de cálcio da lamela media próximo a parede celular, causando extravasamento do conteúdo celular, sintomas da podridão mole. Bactérias do gênero Burkholderia tem se mostrado capazes em controlar a podridão mole em orquídeas, no entanto, os aspectos moleculares envolvidos neste controle ainda não foram estudados. Neste trabalho, foram avaliados 602 transformantes quanto a sua habilidade em inibir os sintomas da podridão mole, onde foram observados 16 mutantes defectivos no controle da doença. Destes, foram identificados sete diferentes genes inativados pelo transposon Tn5, e estes genes podem estar envolvidos em processos de síntese de aleloquímicos, competição por nutrientes, adaptação a condições ambientais, e na interação com o hospedeiro e/ou entre microrganismos. No entanto, o envolvimento destes genes na perda da capacidade em controlar a podridão mole deve ser melhor estudado.The bacterium Pectobacterium carotovora cause damage to different hosts and by production of pectic enzymes that degrade calcium pectate of the middle lamella near of the cell wall, causing overflow of cell content and consequently the soft rot. Burkholderia genus has proven able to control the soft rot in Orchids, however, the molecular aspects involved in the control have not been studied. In this work, 602 transformants were characterized for their ability to inhibit soft rot caused by P. carotovora. We identified 16 mutants showing shifts in inhibition pattern or lost of the ablitity to inhibit soft rot symptoms. Among these mutants, we identified 7 genes related to disease inhibition,and this genes may be involved in process of allelochemicals synthesis, competition for nutrients, adapting to environmental conditions, and interaction between the host and microorganisms. However, the involvement of these genes in loss of ability to control the soft rot disease is being further studied in details.
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Léveillard, Thierry. "Le polymorphisme des gènes de l'inter-alpha-trypsine inhibiteur : recherche d'association génétique avec l'emphysème pulmonaire." Rouen, 1989. http://www.theses.fr/1989ROUES015.
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RFLP des gènes de l'inhibiteur de la trypsine inter alpha chez l'homme, déterminisme génétique et fréquence allélique de ces marqueurs dans une population de référence et dans une population constituée d'individus non déficitaires en alpha-1-antitrypsine souffrant d'emphysème pulmonaire
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Filho, Paulo Roberto de Alcantara. "Caracterização molecular de tumores de mama triplo-negativos com diferença de expressão de SPARC." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/5/5155/tde-16112017-091605/.
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O câncer de mama triplo negativo (TNBC) é um dos tumores mais agressivos, muitas vezes resistentes à terapia sistêmica e com evolução para doença metastática. O entendimento de sua biologia e a concepção de novos tratamentos são essenciais para melhorar o seu prognóstico. Atualmente, as opções de tratamento são reduzidas e a quimioterapia ainda é o tratamento padrão. A expressão de SPARC (secreted protein acidic and rich in cysteine) é supostamente alterada em várias doenças malignas. No entanto, pouco se sabe sobre o valor prognóstico do SPARC em pacientes com TNBC. Usando uma pequena coorte de descoberta de TNBC muito bem caracterizada em relação à expressão do SPARC e comportamento clínico, conseguimos identificar vários genes como diferencialmente expressos na comparação entre amostras de TNBC / SPARC negativo vs. TNBC / SPARC positivo. Cinco desses genes diferencialmente expressos, SOHLH2, DNAJC12, LIM-1, CEACAM-5 e CTAG1A foram escolhidos para serem validados por imuno-histoquímica (IHC) em tissue microarrays (TMAs) contendo uma coorte independente de TNBC. Para acessar o valor prognóstico desses potenciais novos biomarcadores, avaliamos a associação entre a expressão de IHC e os resultados das pacientes pela análise de Kaplan-Meier para a coorte de validação. Foi observado que a coloração negativa da expressão de SOHLH2 e coloração positiva de DNAJC12 e LIM1 mostrou uma tendência a ser correlacionada com um pior prognóstico tanto para a sobrevida livre de doença quanto para sobrevida global. Nossos resultados fornecem novas informações sobre alterações transcriptômicas associadas ao comportamento clínico de TNBC que podem servir como ferramenta potencial para a identificação e caracterização de novos biomarcadores candidatos como fatores prognósticos e preditivos para pacientes com TNBC no futuroTriple-negative breast cancer (TNBC) is one of the most aggressive, therapy-resistant, and metastatic tumors. Understanding of its biology and designing new treatments are essential to improve its prognosis. Currently, treatment options are reduced, and chemotherapy is still the standard treatment. SPARC (secreted protein acidic and rich in cysteine) expression is reportedly altered in various malignancies. However, little is known regarding the prognostic value of SPARC in TNBC patients. Using a small discovered cohort of TNBC very well characterized regarding SPARC expression status and clinical behavior, we were able to identify several genes as differentially expressed in the comparison between TNBC/SPARC negative vs. TNBC/SPARC positive samples. Five of these differentially expressed genes, SOHLH2, DNAJC12, LIM, CEACAM-5 and CTAG1A were chosen to be validated by immunohistochemistry (IHC) on tissue microarrays (TMAs) containing an independent cohort of TNBC. To access the prognostic value of these potential new biomarkers, we evaluated the association between the IHC expression and patient\'s outcomes by Kaplan-Meier analysis for the validation cohort. We found that negative staining of SOHLH2 expression and positive staining of DNAJC12 and LIM1 showed a trend to be correlated with a poor prognosis for both disease-free survival and overall survival. Our findings provide new information on transcriptome changes associated the clinical behavior of TNBC that may serve as a potential tool for the identification and characterization of new candidate biomarkers as prognostic and predictive factors for patients with TNBC in the future
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Pavelescu, Adriana. "Echocardiography for the noninvasive study of the pulmonary circulation: applications to the study of right ventricular effects of targeted therapies of pulmonary hypertension, limiting factors to exercise capacity, and detection of early pulmonary vascular disease in healthy subjects." Doctoral thesis, Universite Libre de Bruxelles, 2012. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209616.
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Ce travail a été consacré à l’étude non invasive de la circulation pulmonaire normale par mise en œuvre de l’échocardiographie Doppler. En intégrant les mesures obtenues dans une approche physiopathologique, et en exploitant les nouvelles possibilités d’échocardiographes portables, techniquement performants, nous avons analysé les effets d’un inhibiteur de la phosphodiestérase-5 et d’une prostacycline, pour tenter d’en identifier d’éventuels effets introtropes intrinsèques, nous avons exploré le concept de réserve vasculaire pulmonaire comme facteur limitant de l’aptitude aérobie et indice potentiel d’une atteinte vasculaire pulmonaire précoce, et obtenu des résultats préliminaires permettant d’identifier une hypertension artérielle pulmonaire (HTAP) latente. Nos principaux résultats peuvent être résumés comme suit :
1. Chez le sujet sain, en normoxie ou dans un modèle expérimental d’HTAP induite par l’inhalation d’un mélange gazeux hypoxique, le sildenafil per os ou l’epoprostenol par voie intraveineuse, à des doses utilisées en clinique pour le traitement de l’HTAP, améliorent les indices de la fonction ventriculaire droite en proportion de leurs effets vasodilatatoires pulmonaires, sans effets inotropes intrinsèques détectables.
2. La consommation d’oxygène maximale du sujet sain augmente en raison directe de son volume capillaire pulmonaire (calculé à partir de sa capacité de diffusion pour l’oxyde nitrique et le monoxyde de carbone) et en raison inverse de sa résistance vasculaire pulmonaire, non seulement en altitude, mais aussi au niveau de la mer. Ce résultat suggère qu’une plus grande réserve vasculaire pulmonaire est propice aux efforts aérobiques intenses, probablement par moindre postcharge ventriculaire droite.
3. Des mesures réalisées chez un petit nombre de sujets suggèrent que la distensibilité vasculaire pulmonaire, calculée à partir d’une relation débit-pression vasculaire pulmonaire, est typiquement réduite chez des porteurs asymptomatiques de la mutation BMPR2, qui est actuellement le facteur de risque le plus élevé connu de l’HTAP. La mutation BMPR2 pourrait aussi être associée à une réactivité vasculaire pulmonaire accrue à l’hypoxie.
Nos résultats suggèrent indirectement que l’échocardiographie Doppler, de repos ou de stress, pourrait être davantage développée dans la mise au point de patients à risque d’HTAP./
Novel advances in echocardiography offer the opportunity to reliably characterize pulmonary circulation in terms of pressure-flow relationship, and to better understand the coupling of right ventricular (RV) function with normal and abnormal pulmonary hemodynamics. Moreover, when combined with the measurement of pulmonary capillary blood volume, this renewed methodological approach may help to understand the concept of pulmonary vascular reserve as a limiting factor of exercise capacity and potential sensitive marker of early vascular disease.
In the present work we used a model of hypoxic pulmonary vasoconstriction to analyse the effects of two targeted therapies of pulmonary arterial hypertension (PAH) on the RV function. We showed that the beneficial effects of these drugs are mainly driven by a decrease in RV afterload and not an enhanced myocardial inotropic state. Whether this is transposable to abnormal RV-arterial coupling in PAH patients remains to be investigated.
Echocardiography may be useful to explore the pulmonary vascular reserve as an important limiting factor of exercise capacity. We showed that a higher pulmonary vascular reserve, defined by a decreased PVR and increased lung diffusing capacity, allows for an improved aerobic exercise capacity (as assessed by a higher peak oxygen consumption), at a lower ventilatory cost, at sea level and at high altitude.
Stress echocardiography may detect an abnormal pulmonary vasoreactivity. We showed that asymptomatic relatives of patients suffering from idiopathic pulmonary arterial hypertension, and who carry a bone morphogenetic protein receptor type 2 mutation (BMPR2) present with a decreased pulmonary vascular distensibility and an enhanced pulmonary vasoreactivity to hypoxia, which are identifiable by echocardiography examination. However, the predictive value of these findings is not known.
Thus echocardiography may represent, in experienced and dedicated hands, a noninvasive, safe, widely available, applicable at the bed-side as well as in extreme environment (e.g. high altitudes), less expensive alternative for the evaluation of the pulmonary circulation, either by the interrogation of pressure-flow relationship (stress echocardiography), by the investigation of the right ventricle global and regional function in relation to its afterload (standard and Tissue Doppler Imaging), or by a combined approach with the measurement of lung diffusing capacity (DLNO / DLCO) to assess the pulmonary vascular reserve.
The present data are encouraging for further development and implementation of echocardiography for the detection, but also the diagnosis and follow-up of patients with pulmonary hypertension.
Doctorat en Sciences médicales
info:eu-repo/semantics/nonPublished
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Hatanaka, Roxanne. "Rastreamento de variantes de significado desconhecido (VUS) no gene RET em indivíduos-controle e em pacientes com carcinoma medular de tireoide." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/5/5135/tde-24022016-111259/.
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Introdução: A Neoplasia endócrina múltipla do tipo 2 (NEM-2) é uma síndrome tumoral de herança autossômica dominante, na qual os tumores associados são carcinoma medular de tireoide (CMT), feocromocitoma (FEO) e hiperparatireoidismo primário (HPT). Esta síndrome ocorre devido a mutações ativadoras no proto-oncogene RET que alteram a via do receptor tirosina quinase RET. Essas mutações levam à ativação constitutiva de vias de sinalização desregulando o ciclo celular. Segundo os Consensos Internacionais de 2001 e 2009 sobre CMT/NEM-2, portadores de mutações no gene RET, inclusive indivíduos assintomáticos, devem ser submetidos a tireoidectomia total (TT) preventiva, aumentando a chance de cura da doença. Não é recomendado rastreamento clínico em portadores que apresentem somente polimorfismos isolados (variante não patogênica). No entanto, existem indivíduos que carregam variantes genéticas de significado clínico desconhecido (VUS), gerando dúvida quanto à conduta clínica. Atualmente, não se tem conhecimento se essas variantes podem ou não estar envolvidas no aumento do risco ao desenvolvimento de CMT. Dessa forma, o presente projeto analisou diversos aspectos como frequência alélica, estudo in silico, dados na literatura e nos bancos genéticos com o intuito de abranger o entendimento dessas variantes e auxiliar na indicação de conduta clínica adequada aos portadores de RET VUS. Objetivo: Expandir o conhecimento do potencial patogênico das VUS do gene RET, focando na classificação controversa da variante p.Y791F. Métodos: Foi realizado o rastreamento dos exons hotspots do gene RET em indivíduos adultos/idosos-controle e em pacientes com CMT através da técnica de Sequenciamento de Nova Geração (NGS) e Sequenciamento de Sanger. Foi também analisada a predição computacional da patogenicidade dessas variantes em seis diferentes programas preditivos. Foi feito o levantamento de dados em diversos bancos genéticos. Resultados: As variantes p.Y791N, p.Y791F e p.E511K foram encontradas no rastreamento genético das amostras-controle sequenciadas. Além dessas variantes, foram identificadas e estudadas famílias de pacientes com CMT portadoras das variantes p.V648I e p.K666N. A variante p.Y791F foi identificada em um novo caso somente com FEO. A análise in silico demonstrou que 4/6 programas foram mais informativos, e que 25/48 VUS demonstram alterar a estrutura físico-química da proteína RET. A frequência alélica encontrada nos bancos de dados de indivíduos-controle e indivíduos com tumores foram bastante baixas. Apenas 15/48 VUS possuem dados sobre estudos in vitro. Conclusão: Nossos dados sugerem que a variante RET p.Y791F, quando isolada e sem coocorrência com mutações conhecidas RET, se comporta como um polimorfismo benigno raro, sem associação do aumento do risco ao CMT. Já a associação de p.Y791F com mutações conhecidas RET, como a C634Y, pode levar ao desenvolvimento de fenótipos atípicos, como maior risco ao feocromocitoma. A variante p.V648I é provavelmente um polimorfismo benigno raro, evidenciado pelo seguimento clínico de aproximadamente 15 anos de uma família portadora dessa variante, sem evidências de CMT, FEO ou HPT. Há necessidade de mais dados para classificar apropriadamente as demais VUS; no entanto, devido a possibilidade das variantes p.E511K, K666N e Y791N poderem ser patogênicas, portadores devem ser monitorados clinicamenteIntroduction: Multiple endocrine neoplasia type 2 (MEN-2) is a tumor syndrome with autosomal dominant inheritance, in which tumors are associated with medullary thyroid carcinoma (MTC), pheochromocytoma (FEO) and primary hyperparathyroidism (HPT). This syndrome occurs due to activating mutations in the RET proto-oncogene, which lead to constitutive activation of tyrosine kinase signaling pathways that deregulate the cell cycle. According to the International Consensus on MTC/MEN-2 of 2001 and 2009 one should recommend that RET mutation carriers, including asymptomatic individuals, should undergo prophylactic total thyroidectomy (TT), increasing the chance of cure of the disease. It is not recommended clinical screening in patients that show only isolated polymorphisms (non-pathogenic variant). However, there are individuals who carry genetic variants of unknown clinical significance (VUS), generating doubt about the best clinical management. Currently, there is no consistent knowledge whether these variants may or may not be involved with the increased risk to MTC. The present project has approached the several aspects of these VUS, such as the allele frequency, in silico pathogenic prediction, published data and public databases, in order to increase our knowledge about VUS, in an attempt to contribute by offering appropriate clinical management to VUS carriers. Objective: To expand the knowledge of the pathogenic potential of some of the VUS of the RET gene, focusing especially on the controversial genetic variant p.Y791F. Methods: We performed the mutation screening of hotspots exons of the RET gene of DNA samples of 2061 adult/elderly healthy individuals and of patients with CMT by Sanger sequencing and Next Generation Sequencing (NGS) techniques. Pathogenic predictions of the studied variants were generated using six genetic softwares. Allelic frequency of RET VUS was assessed in different public databanks. Results: Genetic screening of control samples identified the presence of p.Y791N, p.Y791F and p.E511K germline variants. Patients with MTC carrying p.V648I and p.K666N germline variants were localized and family members were screened and clinically investigated. In addition, a new case with pheochromocytoma was found to carry the p.Y791F germline variant. The in silico analyses showed that 4 out of 6 packages were more informative, suggesting physico-chemical structure alteration caused by 25 out of 48 RET VUS. Very low allele frequencies were found in the public databases including healthy individuals and tumor samples. In vitro studies have been performed only for 15 out of 48 RET VUS. Conclusion: Our data strongly suggest that the p.Y791F variant, when occurring in an isolated form, is a benign polymorphism not associated with increased risk of MTC. Conversely, its co-occurrence with bona fide RET mutations as C634Y may lead to modulation of the phenotype, as increasing the frequencies of large and bilateral pheochromocytomas in MEN2A families. Family members carrying the p.V648I variant isolate have been followed clinically for approximately 15 years. As no indication of MCT, pheochromocytoma or hyperparathyroidism development has been documented, we conclude that this variant is a rare RET benign polymorphism. More information is needed to a better characterization of other VUS as E511K, K666N and Y791N. Thus, carriers with these variants should be necessarily examined through a periodic clinical follow up
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Achatz, Maria Isabel Alves de Souza Waddington. "Modificadores de penetrância de mutações germinativas no gene TP53 em famílias brasileiras com diagnóstico clínico da síndrome de Li-Fraumeni e Li-Fraumeni like: impacto dos polimorfismos intragênicos do TP53 e de genes." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/5/5155/tde-29012009-172419/.
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A síndrome de Li-Fraumeni (LFS) e sua variante like (LFL) são associadas a mutações germinativas no gene TP53 e predispõe ao alto risco para múltiplos tumores em idade jovem. Analisamos 91 famílias LFS/LFL do sul/sudeste do Brasil para mutações germinativas e haplótipos de TP53 (PIN2, PIN3 e PEX4) e MDM2 (309T-G). A mutação R337H ocorreu em 44,4% das famílias avaliadas. Em 750 controles da região a freqüência populacional da mutação foi 0,3%. A genotipagem de oito indivíduos não relacionados R337H-positivos para 29 TAG SNPs intragênicos demonstrou o mesmo haplótipo raro estabelecendo efeito fundador para R337H. O alelo duplicado no PIN3 apresenta impacto modificador e retardo de 17,1 anos na ocorrência de tumores em famílias com mutação no TP53, enquanto o SNP309 MDM2 modula a idade dos sarcomas de partes moles.Li-Fraumeni syndrome (LFS) and its variant like (LFL) are associated with germline mutations in the TP53 gene and predispose to a variety of cancers at an earlier age. We analyzed 91 LFS/LFL families from southern Brazil for germline mutations in TP53 and polymorphisms in TP53 (PIN2, PIN3, PEX4) and MDM2 (309T-G). The germline TP53 mutation R337H was found in 44.4% of all families included. In 750 controls from the same region, mutation prevalence was 0.3%. Genotyping of eight unrelated R337H-positive individuals for 29 intragenic TAG SNPs showed that they all shared the same rare haplotype confirming the founder effect for the mutation. Duplication of PIN3 had a modifier effect on the age of tumor onset (delay of 17.1 years) in TP53 mutation carriers whereas MDM2 SNP309 modulated age of onset for soft-tissue sarcomas.
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Hamy, Anne-Sophie. "Identification of Factors Predicting Sensitivity or Resistance to Neoadjuvant Chemotherapy in Breast Cancer Neoadjuvant treatment : the future of patients with breast cancer Neoadjuvant treatment for intermediate/high-risk HER2-positive and triple-negative breast cancers: no longer an “option” but an ethical obligation Long-term outcome of the REMAGUS 02 trial, a multicenter randomised phase II trial in locally advanced breast cancer patients treated with neoadjuvant chemotherapy with or without celecoxib or trastuzumab according to HER2 status BIRC5 (survivin) : a pejorative prognostic marker in stage II/III breast cancer with no response to neoadjuvant chemotherapy Beyond Axillary Lymph Node Metastasis, BMI and Menopausal Status Are Prognostic Determinants for Triple-Negative Breast Cancer Treated by Neoadjuvant Chemotherapy Pathological complete response and prognosis after neoadjuvant chemotherapy for HER2-positive breast cancers before and after trastuzumab era: results from a real-life cohort The presence of an in situ component on pre-treatment biopsy is not associated with response to neoadjuvant chemotherapy for breast cancer Chemosensitivity, tumor infiltrating lymphocytes (TILs), and survival of postpartum PABC patients treated by neoadjuvant chemotherapy Lymphovascular invasion after neoadjuvant chemotherapy is strongly associated with poor prognosis in breast carcinoma New insight for pharmacogenomics studies from the transcriptional analysis of two large-scale cancer cell line panels Biological network-driven gene selection identifies a stromal immune module as a key determinant of triple-negative breast carcinoma prognosis A Stromal Immune Module Correlated with the Response to Neoadjuvant Chemotherapy, Prognosis and Lymphocyte Infiltration in HER2-Positive Breast Carcinoma Is Inversely Correlated with Hormonal Pathways Stromal lymphocyte infiltration after neoadjuvant chemotherapy is associated with aggressive residual disease and lower disease-free survival in HER2-positive breast cancer Interaction between molecular subtypes, stromal immune infiltration before and after treatment in breast cancer patients treated with neoadjuvant chemotherapy COX2/PTGS2 Expression Is Predictive of Response to Neoadjuvant Celecoxib in HER2-negative Breast Cancer Patients Celecoxib With Neoadjuvant Chemotherapy for Breast Cancer Might Worsen Outcomes Differentially by COX-2 Expression and ER Status: Exploratory Analysis of the REMAGUS02 Trial Comedications influence immune infiltration and pathological response to neoadjuvant chemotherapy in breast cancer." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLS129.
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La chimiothérapie néoadjuvante (CNA) est utilisée dans les cancers du sein agressifs ou localement avancés (CS). Au delà des bénéfices cliniques, elle représente une opportunité pour monitorer in vivo la sensibilité d’une tumeur à un traitement.A partir de l’analyse de sets de données de patients traités par CNA, nous souhaitons identifier des mécanismes associes à la résistance ou sensibilité au traitement. Dans la première partie, nous avons évalué des paramètres, cliniques, anatomopathologiques et transcriptomiques. Nous avons démontré que des éléments non explorés comme la présence d’embols après CNA revêtaient une information pronostique importante. Dans une 2ème partie, nous avons analysé l’impact de l’infiltrat immunitaire dans le cancer du sein, et avons décrit les changements observés entre des échantillons avant et après CNA. Nous avons montré que l’impact pronostique des TILs était différent avant et après CNA, et était opposé dans les CS triple négatif ou HER2-positif. Finalement, nous avons analysé l’impact des comédications pendant la CNA. Nous avons trouvé des effets positifs – via l’augmentation de l’infiltrat immunitaire et la réponse au traitement – et des effets négatifs avec des effets délétères dans certains sous groupes de patients. En conclusion, la situation néoadjuvante représente une plateforme pour générer et potentiellement valider des hypothèses de recherche. La mise à disposition de jeux de données de patients traités par chimiothérapie néoadjuvante constituerait une ressource majeure pour accélérer la recherche contre le cancer du seinNeoadjuvant chemotherapy (NAC i.e. chemotherapy before surgery) is increasingly being used for aggressive or locally advanced breast cancer (BCs). Beyond clinical benefits, it represents an opportunity to monitor in vivo sensitivity to treatment. Based on the analysis of datasets of BCs patients treated with NAC, we aimed at identifying mechanisms associated with resistance or sensitivity to treatment.In the first part, we evaluated biological, clinical, pathological and transcriptomic patterns. We demonstrated that unexplored pathological features such as post-NAC lymphovascular invasion may carried an important prognostic information.In a second part, we analyzed impact of imune infiltration in BC and we described extensively the changes of tumor infiltrating lymphocytes (TILs) between pre and post-NAC samples. We showed that the prognostic impact of TILs was different before and after NAC, and was opposite in TNBC and HER2-positive BCs. Finally, we investigated the impact of comedications use during NAC. We found both positive effects - while enhancing immune infiltration and response to treatment - and negative effects with deleterisous oncologic outcomes in specific patients subgroups. In conclusion, the neoadjuvant setting represents a platform to both generate and potentially validate research hypotheses aiming at increasing the efficacy of treatment. The public release of real-life datasets of BC patients treated with NAC would represent a major resource to accelerate BC research
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Neil, Jason Robert. "TGF-ß promotes cancer progression through the xIAP:TAB₁:TAK₁:IKK axis in mammary epithelial cells /." Connect to full text via ProQuest. Limited to UCD Anschutz Medical Campus, 2008.
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Thesis (Ph.D. in Pharmacology) -- University of Colorado Denver, 2008.Typescript. Includes bibliographical references (leaves 117-147). Free to UCD Anschutz Medical Campus. Online version available via ProQuest Digital Dissertations;