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Fawcett, Jonathan. "Molecular aspects of angiogenesis and metastasis." Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386753.
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Marcu, Loredana Gabriela. "Deterministic modelling of kinetics and radiobiology of radiation-cisplatin interaction in the treatment of head and neck cancers." Title page, contents and abstract only, 2004. http://hdl.handle.net/2440/37961.
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One of the main objectives of combining radiation treatment and chemotherapy is to obtain a therapeutic gain by an improved tumour control with less or no enhancement of normal tissue toxicity. The optimal schedule for the combined treatment of cisplatin-radiation is still under investigation. Neither the optimal time interval, nor the most adequate sequence of administration of cisplatin and radiation are known. The results of the trials are also inconclusive. Some trials showed a supra-additive effect from the administration of cisplatin before radiotherapy, others, on contrary, from the injection of drug after radiotherapy. The present work encompasses the major challenges brought by the combined modality treatment: cisplatin-radiotherapy. The major goal of this work was to investigate the optimal treatment sequencing between cisplatin and radiotherapy and also the optimal schedule for head and neck carcinomas. Therefore, a computer-based tumour model with literature-given biological parameters has been developed which has allowed the simulation of treatment with radiation and chemotherapy. Radiotherapy has been simulated on the virtual tumour and the effects of radiotherapy on tumour regression and regrowth have been analyzed. Also, the mechanisms of cisplatin's action on tumour have been implemented, and the phenomena of drug resistance and tumour repopulation during chemotherapy studied. Finally, the combined modality treatment has been simulated, and the effect of drug-radiation interaction on tumour behaviour evaluated. The current investigation has shown that cisplatin administered immediately before radiation gives similar tumour control to the post-radiation sequencing of the drug. Furthermore, the killing effect of the combined modality treatment on tumour increases with the increase in cell recruitment. The individual cell kill produced by cisplatin and radiation leads to an additive-only tumour response when the treatments are given concurrently, and for a synergistic effect cisplatin must potentiate the effect of radiation. The final conclusion, by which cisplatin administered on a daily basis leads to a better tumour control than cisplatin administered weekly, is in accordance with the latest trial results on head and neck cancers. Therefore, treatment regimens that correlate better with the pharmacokinetics and the radiobiological properties of the therapeutic agents result in better outcomes.Thesis (Ph.D.)--School of Chemistry and Physics, 2004.
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Pitter, Mark C. "Imaging through and analysis of multiply scattering media." Thesis, University of Nottingham, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342072.
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Arora, Ramandeep. "A study of the aetiology and epidemiology of cancers in teenagers and young adults." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/a-study-of-the-aetiology-and-epidemiology-of-cancers-in-teenagers-and-young-adults(effc3dd6-6655-47cd-af95-6eb26cb055c8).html.
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Introduction: Little is known about the aetiology of cancer in teenagers and young adults (TYA) aged 15-24 years, although in England, cancer is the most common cause of disease-related mortality in this age group. The most common cancers at this age are lymphomas, central nervous system (CNS) tumours and germ cell tumours (GCT). The commonest carcinomas seen at older ages including lung, breast, large bowel and prostate account for only 3-4% of TYA cancers. In this thesis I describe the incidence patterns of selected cancers in TYA and the variation seen with geography, time and in population subgroups. The focus is on CNS tumours, GCT and bone tumours as they either peak in incidence in TYA and/or contribute disproportionately to cancer related mortality in TYA. This will allow formulation of hypotheses regarding aetiology of cancer in this age group which can then be tested by further research. Methods: For the majority of the analysis, anonymised national cancer registration data from England on individual patients of all ages with newly diagnosed cancer between 1979 and 2003 were used. To contrast the incidence patterns in England with that of India, data from five Indian urban population based cancer registries were used for part of the analysis. Age, sex, site and histology specific incidence rates were calculated and expressed per million person years. All rates, where appropriate, were adjusted to the world standard population using direct methods. To explore the link of growth with development of osteosarcoma and Ewing sarcoma, a random-effects meta-analysis was undertaken on studies which investigated an association of these tumours with height at diagnosis. Results: The incidence of cancer in TYA overall in England exceeded that of India. This was also true for most individual sites including epithelial cancers of lung, colon/rectum, breast, ovary and cervix, and non-epithelial cancers including melanoma, Hodgkin lymphoma and testicular cancer. Notable exceptions to this pattern were cancers of the mouth, gall bladder and stomach (females only) where incidence was higher in India. In England, CNS tumours in TYA were a composite of pilocytic astrocytomas and embryonal tumours (representing tail end of childhood CNS tumours), pituitary tumours, nerve sheath tumours, high grade astrocytomas and meningiomas (representing early-onset of CNS tumours that peak in incidence in the 6th and 7th decade of life), and of CNS GCTs, pleomorphic xanthoastrocytomas and neurocytomas which show a peak incidence in TYA. Irrespective of site or histology, GCT in England showed a peak in incidence between ages of 10 to 39 years which was more marked in males. This however varied by site and the peak incidence was seen at 10 to 14 years in the CNS, 15 to 19 years in ovary, 25 to 29 in mediastinum & thorax and abdomen & pelvis, and 30 to 34 years in testicular tumours. Osteosarcoma and Ewing sarcoma were the predominant bone tumours in TYA in England and showed a distinct peak of incidence at 10 to 14 years age in females and a larger peak at 15 to 19 years age in males. The peak incidence of osteosarcoma of long bones of the lower limb was six times more than that at any other site while the peak incidence of Ewing sarcomas located in the bones of the central axis exceeded those in long bones of the lower limb. The average height of patients with osteosarcoma at diagnosis was found to be significantly above the average height of the reference population, at the 95% level. The association of greater height at diagnosis with Ewing sarcoma was also significant at the 95% level but much weaker. Conclusion: In this thesis I have explored the epidemiology of cancer in TYA using some of the established methodologies which have previously been used in advancing our knowledge of childhood and older adult cancers. These studies provide some clues to aetiology. Variation in environmental exposures and lifestyle factors between England and India can explain the majority of the differences in incidence patterns observed. Genetic predisposition to cancer along with carcinogen exposure could lead to early onset of some cancers generally seen in older adults. Regardless of site, the similarity in age-incidence patterns of GCT, suggests a common initiation of these tumours in embryonic/foetal life with variable rates of tumour progression as a result of local factors or events during postnatal and pubertal period. The incidence patterns of osteosarcoma along with the strong and consistent association with a greater height at diagnosis indicate that bone growth is important in the development of this tumour while different biological pathways which may be unrelated to growth could also be relevant for Ewing sarcoma.
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McConechy, Melissa. "PPP2R1A mutations in gynaecologic cancers: functional characterization and use in the genomic classification of tumours." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/52829.
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Endometrial carcinoma is the most common gynaecological cancer in developed countries. The current endometrial pathologic classification system lacks reproducibility, which has hampered the development of new treatments for these cancers. The PP2A phosphatase complexes are responsible for regulating many cellular pathways, and may play a role in the deregulation of endometrial cancer-associated pathways.
In this thesis, the role of PPP2R1A mutations in the subtype-specific classification of gynaecological tumours was investigated. Additionally, mutational profiles will be used to improve the classification of the subtypes of endometrial carcinomas. Lastly, the functional effect of mutant PPP2R1A on PP2A-subunit protein interactions will be determined, in the context of endometrial cancer cell lines.
Next-generation and Sanger sequencing was used to determine the presence of mutations in endometrial and ovarian carcinomas. PPP2R1A isogenic endometrial-specific cell lines were generated using somatic cell gene knockout by homologous recombination. Co-immunoprecipitation and mass spectrometry was used to determine effects of the PPP2R1A W257L mutation on its ability to interact with PP2A subunits.
Subtype-specific somatic PPP2R1A mutations were identified in endometrial serous carcinomas. Low-grade endometrial endometrioid carcinomas were defined by mutations in the genes: ARID1A, PTEN, PIK3CA, CTNNB1, and KRAS, whereas high-grade endometrioid also harbor TP53 mutations. Endometrial serous carcinomas harbor mutations in PPP2R1A, FBXW7, PIK3CA and TP53. Consequently, the molecular profiles proved useful in assisting classification of tumours with overlapping morphological features that cause irreproducibility in diagnoses. Proteomic analysis of isogenic cell lines determined that the PPP2R1A W257L mutation disrupts interaction with PPP2R5C and PPP2R5D subunits. In addition, PPP2R1A mutated protein caused an increased interaction with the endogenous PP2A inhibitor SET/I2PP2A.
The integration of mutational profiles and other genomic features will be used to improve clinical and pathological classification in endometrial tumours that are difficult to diagnose. PPP2R1A mutations are likely playing a role in the transformation of gynaecological carcinoma, by disrupting PP2A subunit interactions with tumour suppressor functions. Increased interaction of mutant PPP2R1A with SET/I2PP2A adds another layer of complexity to the tumour suppressive role of PP2A. In the future, targeting the PP2A complex with novel therapeutics could provide an alternative method for treating gyneacological cancers with poor outcomes.Medicine, Faculty of
Pathology and Laboratory Medicine, Department of
Graduate
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Kaewkangsadan, Viriya. "Evaluation of immune cell infiltrates and expression of cytokines/biological molecules in the microenvironment of tumours and tumour-draining axillary lymph nodes in patients with large and locally advanced breast cancers undergoing neoadjuvant chemotherapy : crucial contribution to immune-mediated tumour cell death." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/34155/.
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Background: Neoadjuvant chemotherapy (NAC) is being used as first line treatment in women with large and locally advanced breast cancers (LLABCs). However, the response to NAC is difficult to predict. Growing evidence suggests that these patients are immunosuppressed and that circulating immunosuppressive regulatory cells and humoral factors affect the response to NAC. We explored the possible role of the in situ tumour immune milieu in inducing and affecting the responses to NAC, and the contribution of concomitant systemic circulating regulatory cells. Methods: Paraffin-embedded breast cancers and ipsilateral axillary lymph nodes (ALNs) from pre- and post-NAC samples of a cohort of 33 women with LLABCs, 16 of whom had their blood regulatory cells previously investigated. Various immune cell infiltrations and expression of cytokines/biological molecules in the specimens were studied using appropriate monoclonal antibodies and immunohistochemistry. Statistical analysis was carried out using non-parametric tests with SPSS version 21. Results: High levels of pre-NAC tumour-infiltrating lymphocytes (TILs) (p < 0.001) and subsets of CD4⁺T cells (intratumoural, p=0.023; peritumoural, p=0.001), CD8+T cells (intratumoural, p=0.008; peritumoural, p=0.002) and CD56⁺NK cells (intratumoural, p=0.001; peritumoural, p < 0.001) were significantly associated with a pathological complete response (pCR). High levels of CD163⁺macrophages were also significantly associated with a good pathological response (p=0.004) and pCR (p=0.008). There was a positive correlation between the CD8:FOXP3 ratio and grade of pathological response. In multivariate analyses, TILs and peritumoural CD56+NK cells were found to be independent predictive factors for pCR. There was a significantly high expression of IL-10 in post-NAC breast specimens with poor responses to NAC (p < 0.001). NAC significantly reduced infiltrating T regulatory cells (Tregs) (p=0.001) and PD1⁺T cells (p=0.005), as well as expression of IL-4 (p=0.016). There was no significant difference between the percentages (%) of immune cells present in ALNs with or without metastases but there was a T helper-2 cytokine polarisation in metastatic ALNs. Metastatic ALNs with a high % of CD8+T cells (p=0.048) and low % of FOXP3+Tregs (p=0.019) were significantly associated with an ALN pCR. There was a significantly positive correlation between circulating and intratumoural infiltrating Tregs following NAC (p=0.003). Conclusions: The tumour immune microenvironment is a key factor in achieving a good pathological response with NAC. Tumour and blood immune parameters may be clinically useful in identifying women with LLABCs likely to respond to NAC. Our findings also suggest that the beneficial effects of NAC are mediated via modulation of anticancer immunity, in particular by reduction of T regulatory cells and immunosuppressive humoral factors.
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Burns, Alice Sin Ying Wai. "The role of the p53 tumour suppressor pathway in central primitive neuroectodermal tumours." Thesis, University of Newcastle Upon Tyne, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300357.
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Morel, Daphné. "Identifying Synthetic Lethal and Selective Approaches to Target PBRM1-Deficiency in Clear Cell Renal Cell Carcinoma PBRM1 Deficiency in Cancer is Synthetic Lethal with DNA Repair Inhibitors Exploiting Epigenetic Vulnerabilities in Solid Tumors: Novel Therapeutic Opportunities in the Treatment of SWI/SNF-Defective Cancers Combining Epigenetic Drugs with other Therapies for Solid Tumours — Past Lessons and Future Promise Targeting Chromatin Defects in Selected Solid Tumors Based on Oncogene Addiction, Synthetic Lethality and Epigenetic Antagonism." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASL017.
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L’inactivation de polybromo-1 (PBRM1) est un évènement fréquent dans de nombreux cancers. En particulier, les carcinomes rénaux à cellules claires présentent une déficience en PBRM1 dans 40 à 50% des cas. A ce jour, il n’existe pas d’approche de médecine précision connue capable de cibler spécifiquement les cellules tumorales déficientes en PBRM1.Pour identifier des cibles de létalité synthétique associées à la perte de PBRM1, nous avons (i) réalisé un criblage pharmacologique à haut débit évaluant la sensibilité à 167 molécules dans un modèle cellulaire isogénique pour PBRM1, et (ii) étudié l’impact transcriptomique et protéomique de la perte de PBRM1 dans ce même modèle.Nous avons ensuite caractérisé les mécanismes sous-jacents à la relation de létalité synthétique découverte.Nous avons identifié et validé une relation de létalité synthétique existante entre la perte tumorale de PBRM1 et l’inhibition pharmacologique de PARP, pouvant être potentialisée par l’ajout d’un inhibiteur d’ATR.Cette relation de létalité synthétique était caractérisée par un niveau basal élevé de stress cellulaire chez les cellules déficientes en PBRM1, associant anomalies mitotiques, stress transcriptionnel et stress réplicatif – tous ces phénomènes étant exacerbés à l’ajout d’inhibiteurs de PARP, jusqu’à dépasser les capacités cellulaires à maintenir un phénotype compatible avec la survie.Ces observations apportent la preuve de concept préclinique que les inhibiteurs de PARP sont de potentiels candidats thérapeutiques pour cibler spécifiquement les tumeurs déficientes en PBRM1Polybromo-1 (PBRM1) inactivation occurs in multiple malignancies and is of particular importance in clear cell renal cell carcinomas (ccRCC), as it drives 40 to 50% of cases. Currently, no precision-medicine approach uses PBRM1 deficiency to specifically target tumour cells. To uncover novel synthetic lethal approaches to treat PBRM1-defective cancers, we performed (i) a high-throughput pharmacological screening, evaluating the sensitivity to 167 small molecules in a PBRM1-isogenic cellular model, and the (ii) systematic mapping of the whole transcriptomic and proteomic profiles associated with PBRM1 loss-of-function within this model. We further investigated the mechanism underlying this synthetic lethal relationship.We identified and validated synthetic lethal effects between PBRM1 loss and both PARP and ATR inhibition. Combinatorial use of PARP with ATR inhibitors exerted additive cytotoxic effects in PBRM1-defective tumor cells. These synthetic lethal relationships were characterized by a pre-existing replication stress in PBRM1-deficient cells associated with mitosis and DNA damage repair abnormalities, which were exacerbated upon PARP inhibition selectively in PBRM1-defective cells.These data provide the preclinical basis for evaluating PARP inhibitors as a monotherapy or in combination in patients with PBRM1-deficient ccRCC
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Chambers, George. "A study of the production of the selected cytokines interleukin 1, interleukin 6, and tumour necrosis factor by certain tumours and tumour cell lines." Thesis, University of Glasgow, 1996. http://theses.gla.ac.uk/4041/.
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An investigation was carried out to examine the production of the inflammatory cytokines IL1, IL1, IL6, TNF, and TNF in two tumour cell lines, the MCF-7 breast cell line and the T-24 bladder cell line, and in samples of breast, bladder, lung and ovarian tumours. Two methods were used to investigate cytokine production. These were the polymerase chain reaction method (PCR) to examine cytokine mRNA production and immuno-staining of frozen or paraffin-embedded tissue sections to demonstrate the presence of the cytokine polypeptide directly. In the PCR experiments, the most frequently found cytokine was IL6, followed by IL1. Only a few tumours of any type displayed TNF, and even fewer produced TNF. In the immunostaining experiments performed on frozen sections, IL1 and IL6 proteins were detected in sections of tumours which gave positive results with PCR. Cell phenotyping indicated that the IL1 and IL6 were probably being synthesised by the tumour cells themselves although there was lymphocyte infiltration in every section examined. In the immuno-histology study performed on the paraffin-embedded sections, a new collection of tumours was used. These tumours were not subjected to parallel PCR due to size of tumour samples being too small. The results obtained from these experiments conflicted with the results observed in the PCR study. IL1 was detected in all of the breast tumours used for immuno-histology but in none of the breast tumours in the PCR experiments. While the conflict could not definately be resolved, it was thought that the results of the immuno-histology experiments were more accurate as they detected expression of cytokine protein on a cellular scale. The immuno-histology experiments demonstrated that some tumour cells produced IL1 in breast and bladder carcinomas, and some produced IL6 in breast and lung carcinomas.
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Bundell, Christine Stephanie. "Immune recognition and editing of tumours expressing multiple antigenic epitopes in two murine models." University of Western Australia. School of Medicine and Pharmacology, 2007. http://theses.library.uwa.edu.au/adt-WU2007.0067.
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[Truncated abstract] The design of effective immunotherapies, using tumour antigens to stimulate a functional effector cytotoxic T cell (CTL) response in a tumour bearing host, requires an understanding of the 'real time' in vivo relationship between the host immune system and antigens expressed by the developing tumour. However, effector function of endogenous anti-tumour CTLs generated during tumour progression has largely been assessed by indirect ex vivo assays and often focused on a single antigen. Therefore, studies in this thesis evaluated the endogenous in vivo CTL response to multiple tumour antigenic epitopes in murine tumour models using Lewis lung carcinoma cells transfected with ovalbumin (an antigen that contains several intra-molecular MHC class I epitopes with a defined hierarchy) or a polyepitope (that contains a string of immunodominant MHC class I epitopes). Potent effector CTLs were generated to multiple dominant tumour antigenic epioptes early in tumour progression. However, in general, these CTL effectors only transiently retarded tumour growth, and at the later time points of tumour growth they were no longer generated in tumour draining lymph nodes. This coincided with diminished tumour antigen presentation in the same nodes which was found to be due to antigen loss. In both models antigen loss was the result of two processes; immuno-editing of the tumour by the host immune response and genetic instability resulting in antigen loss variants that could evade immune surveillance. A third model was generated that maintained low level tumour antigen expression throughout tumour progression. ... The impact of pre-existing endogenous dominant-epitope specific CTLs on tumour expressing the same epitope was also assessed, and resulted in a reduced tumour incidence and a CTL response restricted to a single antigen of the same MHC allele. Finally, the effects of two different immunotherapy regimens were examined. Intratumoural IL-2 treatment enhanced pre-existing CTL responses to the dominant epitopes leading to tumour regression. In addition, use of a multiple peptide vaccination regimen that avoided T cells competing for peptide-MHC complexes on APC was far more likely to be effective than one that did not. These results demonstrate that immunotherapies targeting tumours that express several dominant neo antigenic epitopes can be effective. The caveat for this approach is that it will only be effective in tumours that have generated an endogenous CTL response and must be used before antigen loss variants emerge.
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Siesjö, Peter. "Immunotherapy of rat brain tumors with mutagen induced, cross-reactive tumor cell variants." Lund : Section of Tumor Immunology, Dept. of Cell and Molecular Biology, University of Lund, 1997. http://books.google.com/books?id=TXZrAAAAMAAJ.
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Kroll, Mary Eileen. "Time trends in childhood cancer : Britain 1966-2005." Thesis, University of Oxford, 2009. http://ora.ox.ac.uk/objects/uuid:8be887be-36e7-4b77-a7af-5887f3a1df8c.
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Increasing time trends in the recorded incidence of childhood cancer have been reported in many different settings. The extent to which these trends reflect real changes in incidence, rather than improvements in methods for diagnosis and registration, is controversial. Using data from the National Registry of Childhood Tumours (NRCT), this thesis investigates time trends in cancer diagnosed under age 15 in residents of Britain during 1966-2005 (54650 cases), and considers potential sources of artefact in detail. Several different methods are used to estimate completeness of NRCT registration. The history of methods for diagnosis and registration of childhood cancers in Britain is described, and predictions are made for effects on recorded incidence. For each of the 12 main diagnostic groups, Poisson regression is used to fit continuous time trends and ‘step’ models to the annual age-sex-standardised rates by year of birth and year of diagnosis. Age-specific rates by period, and quinquennial standardised rates for diagnostic subgroups, are shown graphically. For three broad groups (leukaemia, CNS tumours and other cancer), geographical variation is compared by period of diagnosis. The results of these analyses are discussed in relation to the predicted artefacts. The evidence for a positive association between affluence and recorded incidence of childhood leukaemia is briefly reviewed. A special form of diagnostic artefact, the ‘fatal infection’ hypothesis, is proposed as an explanation of both this association and the leukaemia time trend. This hypothesis is examined in a novel test based on clinical data. The recorded incidence of childhood cancer in Britain increased in each of 12 diagnostic groups during 1966-2005 (from 0.5% per year for bone cancer to 2.5% for hepatic cancer, with 0.7% for leukaemia). Evidence presented here suggests that these increases are probably artefacts of diagnosis and registration. The potential implications for epidemiological studies of childhood cancer should be considered.
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Hartman, Caio Augusto 1977. "Ultrassonografia e CA-125 como preditores de malignidade em mulheres com tumores anexiais." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/312140.
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Orientadores: Sophie Françoise Mauricette Derchain, Cássia Raquel Teatin JuliatoDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
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Resumo: Introdução: O câncer de ovário é a mais letal das neoplasias ginecológicas e representa a quinta causa mais comum de morte por câncer em mulheres. A sobrevida é baixa e não ultrapassa 40% após 5 anos e está diretamente relacionada ao estádio da doença ao diagnóstico. Não há até hoje, nenhum método de rastreamento que se mostrou efetivo na redução da mortalidade por esta neoplasia. Entretanto, a ultrassonografia (US) e o CA-125 são muito utilizados na diferenciação das tumorações anexiais. Apesar de todos os estudos realizados com US, não existe um consenso sobre os critérios a serem utilizados na diferenciação pré-operatória destes tumores. Frente ao achado de um tumor anexial, o ginecologista deve avaliar o risco de malignidade do mesmo, para instituir um preparo pré-operatório mais adequado, prever a extensão do procedimento e suas possíveis complicações. Objetivo: avaliar os critérios ultrassonográficos de Timmerman et al. e os valores do CA-125 como indicadores de risco para malignidade em mulheres com tumores anexiais. Sujeitos e métodos: este é um estudo de corte transversal no qual foram incluídas 105 mulheres, com 112 tumores anexais. Estas foram submetidas a coleta de sangue periférico para dosagem de CA-125 e exame de ultrassonografia (US). O exame de US foi realizado utilizando descrição padronizada. Informações sobre mais de 40 variáveis morfológicas e de Doppler foram coletadas. A seguir, os tumores anexiais foram classificados segundo 5 critérios de benignidade: (B1) cisto unilocular, (B2) presença de componentes sólidos menores que 7mm, (B3) presença de sombra acústica, (B4) tumor multilocular com paredes lisas medindo menos que 100mm e (B5) ausência de fluxo ao Doppler (índice de cor 1). Os 5 critérios de malignidade foram: (M1) tumor sólido irregular, (M2) presença de ascite, (M3) presença de pelo menos 4 projeções papilíferas, (M4) tumor multilocular sólido irregular com maior medida ? 100mm e (M5) alto fluxo ao Doppler (índice de cor 4). O padrão-ouro foi considerado o resultado do exame anátomo patológico das peças cirúrgicas. Resultados: dos 112 tumores, 81 (72,3%) eram benignos e 31 (27,7%) malignos. Os critérios ultrassonográficos foram aplicáveis a 91 (81,2%) dos tumores e resultaram em sensibilidade de 90% e especificidade de 87%. Nos tumores não classificáveis segundo os critérios, utilizamos a avaliação subjetiva para classificá-los como benignos ou malignos e obtivemos sensibilidade de 66,7% e especificidade de 75%. O CA-125 apresentou sensibilidade de 69% e especifidade de 87,8%. Nos tumores ultrassograficamente classificados como benignos, tanto a idade como os valores do CA-125 não contribuíram adicionalmente para a detecção dos tumores histologicamente malignos. Já no grupo de tumores ultrassonograficamente classificados como malignos, a idade e os valores de CA-125 contribuíram significativamente para a detecção de tumores histologicamente malignos (p = 0.025). Conclusões: A maioria dos tumores pode ser corretamente classificada segundo os critérios ultrassonográficos, com sensibilidade e especificidade semelhantes a do estudo original de Timmerman. O CA-125 isoladamente apresentou menor desempenho que o US na discrimação de tumores anexiais. Quando associamos o CA-125 à idade e aos critérios ultrassonográficos em um modelo de regressão logística, obtivemos melhora no desempenho na discriminação dos tumores ultrassograficamente malignos
Abstract: Introduction: Ovarian cancer is the deadliest gynecologic neoplasm and it is the fifth leading cause of cancer-related deaths in women. The survival rate is low, not exceeding 40% after 5 years and is directly related to tumor stage at the time of diagnosis. To date there is still no screening method that is effective at reducing mortality from this neoplasm. However, ultrasonography and CA-125 are widely used in the differentiation of adnexal tumors. Despite all studies conducted with US, there is no consensus on the criteria to be used in the preoperative differentiation of these tumors. When an adnexal tumor is found, the gynecologist should assess the risk of tumor malignancy to institute a more appropriate preoperative preparation, predict the extension of the surgical procedure along with its potential complications. Objective: to evaluate ultrasound criteria of Timmerman et al. and CA-125 values as indicators of malignancy risk in women with adnexal tumors. Subjects and methods: a prospective study was conducted, including 105 women with 112 adnexal tumors. These women underwent peripheral blood collection for CA-125 measurement and ultrasound (US). US evaluation was performed by using standardized classification. Information on more than 40 morphologic and Doppler variables was obtained. Adnexal tumors were then classified according to 5 features of benign disorders: (B1) unilocular ovarian cyst, (B2) presence of solid components in which the largest solid component is < 7mm, (B3) presence of acoustic shadows, (B4) multilocular tumor with smooth walls measuring less than 100mm and (B5) no detectable Doppler flow (color score 1). The 5 features of malignancy were: (M1) irregular solid tumor, (M2) presence of ascites, (M3) presence of at least 4 papillary projections, (M4) irregular solid multilocular tumor with largest measurement ? 100mm and (M5) high color content on Doppler exam (color score 4). Histopathological analysis of surgical specimens was considered the gold standard. Results: among the 112 tumors, 81 (72.3%) were benign and 31 (27.7%) were malignant. Ultrasound criteria were applicable to 91 (81.2%) of the tumors and resulted in a sensitivity of 90% and specificity of 87%. In tumors not classifiable according to criteria, we used subjective assessment to classify these tumors as benign or malignant, obtaining a sensitivity of 66.7% and specificity of 75%. CA-125 had a sensitivity of 69% and specificity of 87.8%. In tumors sonographically classified as benign, both age and CA-125 values did not contribute any further to the detection of histologically malignant tumors. In contrast, in the group of tumors classified as malignant on ultrasound, the age and the CA-125 values contributed significantly to the detection of histologically malignant tumors (p = 0.025). Conclusions: The majority of tumors may be correctly classified according to ultrasound criteria, with sensitivity and specificity similar to those of the original study by Timmerman. Measurement of CA-125 levels alone showed a worse performance than US evaluation in discriminating adnexal tumors. CA-125 measurement associated with age and ultrasound criteria in a logistic regression model, resulted in a better performance in discriminating the sonographically malignant tumors
Mestrado
Oncologia Ginecológica e Mamária
Mestre em Ciências da Saúde
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Grochot, Rafael Maciel. "Expressão do PD-L1 em neoplasias cervicais e seu impacto em sobrevida associado à infiltração linfocitária peritumoral e à expressão de FOXP3." reponame:Repositório Institucional da UCS, 2018. https://repositorio.ucs.br/11338/3902.
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Soldatelli, Jéssica Silveira. "Efeitos da combinação de temozolomida e ditelureto de difenila em linhagens celulares de glioblastoma." reponame:Repositório Institucional da UCS, 2018. https://repositorio.ucs.br/11338/4064.
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Os gliomas representam mais de 70% dos tumores cerebrais primários. Os glioblastomas multiformes são gliomas malignos caracterizados por baixa incidência, mas altas taxas de mortalidade. Apesar da responsividade inicial ao tratamento padrão realizado com o quimioterápico alquilante temozolomida (TMZ), poucos foram os avanços para o prognóstico dos pacientes nos últimos 10 anos. Isso deve-se ao fato desses tumores serem raramente passíveis de ressecção cirúrgica e apresentarem alta taxa de recorrência. Além disso, a eficácia de seu tratamento encontra barreiras como efeitos colaterais indesejáveis e resistência quimioterápica. Nesse cenário, a descoberta de novas substâncias que possam atuar com efeito aditivo ou sinérgico e aumentem a sensibilização de células tumorais ao tratamento, torna-se uma estratégia terapêutica no campo da oncologia. O ditelureto de difenila (DTDF) é um composto orgânico contendo telúrio que apresenta interessantes efeitos biológicos in vitro, como antioxidante, quimioprotetivo, citotóxico e antitumoral. Sendo assim, o objetivo deste estudo foi avaliar os efeitos do DTDF e do quimioterápico TMZ, em regimes isolados e em associação. Para tal foram investigados seus efeitos citotóxicos, após exposição aguda e crônica, em culturas celulares de glioma não-resistente (M059J) e resistente à TMZ (GBM). No ensaio de viabilidade celular a TMZ apresentou citotoxicidade para as linhagens celulares testadas, com valor de IC50 maior na linhagem resistente do que quando comparado à linhagem não-resistente. Este dado foi confirmado pelo teste de duplicação cumulativa de população e, também, pela coloração com laranja de acridina, após o tratamento de 120 h, por observar-se um aumento na frequência de células positivas para a formação de organelas vesiculares ácidas em ambas as linhagens, sendo predominantemente em células GBM. Além disso, foi observado que o tratamento associando DTDF e a TMZ apresentou uma maior citotoxicidade quando comparado aos tratamentos isolados, após 120 h de tratamento. Portanto, o DTDF sensibilizou as células ao tratamento com TMZ. Essa sensibilização ocorreu em níveis aproximados para ambas as linhagens, sendo os efeitos do DTDF independentes do perfil de resistência à TMZ. Em conjunto, os dados desse trabalho sugerem o uso do DTDF em associação à TMZ como uma estratégia para reduzir as doses de TMZ empregadas na clínica e diminuir efeitos colaterais aos pacientes em tratamento de gliomaGliomas represent more than 70% of primary brain tumors. Malignant gliomas are characterized by low incidence, but high mortality rates. Despite the initial responsiveness to the standard treatment with the chemotherapeutic alkylating temozolomide (TMZ), few advances have been made in the prognosis of patients in the last 10 years. This is due to the fact that these tumors are rarely amenable to surgical resection and have a high rate of recurrence. Moreover, the effectiveness of this treatment encounters barriers such as undesirable side effects and chemotherapeutic resistance. In this scenario, the discovery of new substances that may act with additive or synergistic effect and increase the sensitization of tumor cells to the treatment becomes a therapeutic strategy in the field of oncology. Diphenyl ditelluride (DPDT) is a derivative of tellurium used in various reactions of organic synthesis and has interesting in vitro biological effects, as antioxidant, chemoprotective, cytotoxic and antitumor agent. Therefore this work aimed to evaluate the cytotoxic effects of this organotellurium compound and the chemotherapeutic, TMZ, in isolated and in association regimens, after acute and chronic exposure, of non-resistant (M059J) and TMZ- resistant (GBM) glioma cells. Through the cell viability assay, it was shown that TMZ is cytotoxic for both cell lines tested, showing a higher IC50 value in the resistant line when compared to the other line. This data was confirmed by the cumulative population doubling test. In addition, by the acridine orange staining, it was verified that autophagy might favor the chemoresistance, although not being the main resistance mechanism in the lines tested. It was observed that DPDT clearly has a dose-dependent cytotoxic effect on the M059J and GBM cell lines, in a lower concentration range than that used with TMZ. DPDT sensitized the cells to TMZ treatment as evidenced by the decline in cell viability. It is important to point out that this sensitization occurred in low and approximate IC50 values after both 24 h and 120 h of treatment, being the effects of the DPDT independent of the resistance profile to TMZ. Taken together, data from this work suggest the use of DPDT in association with TMZ as an interesting strategy to reduce the doses of TMZ used in the clinic and to reduce side effects to patients under treatment of glioma.
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Pike, Luke R. G. "The role of ATF4 in hypoxia-induced cell death in cancer." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:f32e03f9-0bd2-4dd1-8320-b082b9b2d363.
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Cancer cells survive the harsh oxygen and nutrient deprivation of the tumour microenvironment through the selection of apoptosis-resistant and glycolytic clones (Cairns et al., 2011; Graeber et al., 1996). In particular, the integrated stress response (ISR) has been shown to be pivotal in cancer cell survival in vivo and the resistance of cancer cells to therapy (Harding et al., 2003). In recent years, it has become apparent that increased autophagy is one mechanism by which the ISR can confer resistance to stress (Kroemer et al., 2010). ATF4 is a major transcriptional effector of the integrated stress response in severe hypoxia (<0.01% O₂). ATF4 is a well-established regulator of genes involved in oxidative stress, amino acid synthesis and uptake, lipid metabolism, protein folding, metastasis, and angiogenesis. Recent work has demonstrated an important role of ATF4 in promoting resistance to severe hypoxia through the transcriptional upregulation of MAP1LC3B and ATG5, essential components of the autophagy machinery (Rouschop et al., 2009b; Rzyski et al., 2010). In this work, the author describes several novel ATF4 target genes, and examines their role in the regulation of autophagy and the resistance of cancer cells to severe hypoxia. In the first part of this thesis, the author shows that three BH3-only members of the BCL-2 family of proteins--HRK, PUMA, and NOXA--are upregulated in response to severe hypoxia in an ATF4-dependent manner. In particular, the author shows that the poorly described BH3-only protein HRK is a direct target of transcriptional activation by ATF4, and that HRK induces autophagy in severe hypoxia, thereby providing the first evidence that the integrated stress response can transcriptionally trigger the autophagy process. In contrast to the previously described role of HRK in apoptosis, this thesis demonstrates that HRK can play a pro-survival role in the context of breast cancer cells. In the latter part of this thesis, the author identifies the essential autophagy gene ULK1 as an ISR target. The author shows that ULK1 expression in severe hypoxia is transcriptionally upregulated through direct activation by ATF4. The author identifies ULK1 as a crucial regulator of autophagy and mitophagy in both normoxia and severe hypoxia and shows that ULK1 plays a pivotal role in cancer cell survival. Furthermore, it is shown that human breast cancer patients with high levels of ULK1 relapse earlier than those with low levels of ULK1, thereby identifying ULK1 as a potential target for cancer therapy.
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Kakkar, Ajay Kumar. "Tissue factor, thrombin generation and cancer." Thesis, Imperial College London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.286352.
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Lan, Fong Wong Te Fong. "Tumour angiogenesis in epithelial ovarian cancers." Thesis, University College London (University of London), 2007. http://discovery.ucl.ac.uk/1446159/.
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Epithelial ovarian cancer (EOC) is the most lethal gynaecological malignancy. It is frequently diagnosed late and shows poor prognosis with a 5 year survival rate of 30%. New blood vessel formation (angiogenesis) and new lymphatic vessel growth (lymphangiogenesis) are fundamental events in tumour growth and metastatic dissemination. Despite the existence of established clinical prognostic markers for EOC, there is still a lack of clinically reliable molecular markers for assessing prognosis. In addition, little is known about the molecular events underlying EOC formation and spread. The aim of the study was to identify additional prognostic parameters in EOC and potentially pre-malignant ovarian lesions and to understand the potential mechanisms of angiogenesis / lymphangiogenesis in EOC formation. Archival paraffin wax-embedded sections, frozen tissues, serum and fluid samples of pre-malignant ovarian lesions (endometriosis, benign cystadenomas and borderline tumours) and EOC were used to assess molecular changes in EOC and these ovarian lesions compared to normal ovaries. Techniques used included immunohistochemistry, ELISA, and real-time quantitative RT-PCR which were performed to analyse molecular markers of angiogenesis and lymphangiogenesis (VEGF, VEGF-C, VEGFR-1, VEGFR-2, TP and MVD). IGF-1 isoforms involved in cell proliferation, repair and angiogenic regulation were analysed. Both VEGF and TP expression increased significantly in the formation of endometriotic and borderline lesions. VEGF-C was high in benign cystadenomas and borderline tumours. Serum VEGF levels were higher in EOC compared to premalignant benign ovarian lesions and controls, particularly in clear cell and endometrioid EOC subtypes. There was no correlation between serum VEGF and matched platelet counts. Expression of IGF-1 Ea and VEGF increased significantly from normal ovary to EOC, suggesting that VEGF may be under the regulation of IGF-lEa. This analysis has revealed the molecular interplay of angiogenic and lymphangiogenic pathways in ovarian carcinogenesis.
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Taylor, Charles Dariush. "Structural characterisation and analysis of human cripto-1." Thesis, University of Oxford, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.670042.
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Bolger, Brendan Stephen. "Cell cycle kinetics in cervical tumours." Thesis, Imperial College London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294984.
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Ricardo, Sara Alexandra Vinhas. "Identifying cancer stem cells in breast tumours: searching for cancer origins." Tese, Instituto de Ciências Biomédicas Abel Salazar, 2011. http://hdl.handle.net/10216/56648.
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Ricardo, Sara Alexandra Vinhas. "Identifying cancer stem cells in breast tumours: searching for cancer origins." Doctoral thesis, Instituto de Ciências Biomédicas Abel Salazar, 2011. http://hdl.handle.net/10216/56648.
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King, Catherine Anne. "Idiotypic vaccination against B cell tumours." Thesis, University of Southampton, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241861.
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Patel, Keval Mahendra. "Circulating tumour DNA in localised urological cancers." Thesis, University of Cambridge, 2017. https://www.repository.cam.ac.uk/handle/1810/268065.
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There is a need for informative biomarkers in localised urological cancers. At present, no method can accurately distinguish between indolent and aggressive prostate cancers, and men often require repeated biopsies. Patients with muscle invasive bladder cancer undergo neo-adjuvant chemotherapy (NAC) to improve survival. However many do not respond to NAC, delaying definitive treatment. Cell-free mutant DNA (mutDNA) analysis represents an opportunity for non-invasive monitoring of cancer through tumour genome analysis. MutDNA derived from plasma can monitor tumour burden. There is emerging evidence that mutDNA can identify mutations from multiple clones and is abundant in adjacent body fluids. This work explores the utility of plasma and urinary mutDNA in localised prostate and bladder cancers. This thesis describes the optimisation of urinary mutDNA analysis by assessing urinary DNA processing and extraction methods using healthy volunteer and bladder cancer patient urine samples. Primer panels were designed and validated to target frequently mutated regions in prostate and bladder cancers, as well as for analysis of patient-specific mutations. Sequencing-based methods and dPCR were employed to analyse clinical samples including plasma and urine, to detect and quantify mutDNA. Molecular and clinical data were integrated to explore potential areas of application of mutDNA analysis. For bladder cancer, mutDNA was analysed from liquid-biopsy samples including plasma, cell pellets from urine and urine supernatant from multiple time-points of 17 MIBC patients undergoing NAC. I showed that mutDNA was more frequently detected and was present at higher AFs in urine compared to plasma samples. Of potential clinical relevance, I showed that the presence of mutDNA after starting NAC was associated with disease recurrence. This original contribution to knowledge could offer patients an opportunity to expedite surgical resection in a timely manner, if corroborated in large-scale trials. For prostate cancer, a TP53 specific panel was applied to men with metastatic disease, to demonstrate that clones containing TP53 mutations, which are dominant in at the metastatic stage were present in historical prostatectomy samples taken when then patient was believed to have localised disease only. Furthermore, I showed that these TP53 mutations could be detected at the localised stage of disease. To investigate the ability of mutDNA detection private clonal mutations I developed a method for higher sensitivity analysis (MRD-Seq). This was applied to a clinical cohort of 2 men with multi-focal localised prostate cancer to demonstrate the though the overall levels of mutDNA is low, private clonal mutations may be detectable. Taken together, these original contributions to knowledge could allow for less invasive surveillance of men with low risk prostate cancer and warrants further investigation. In this thesis, I used a range of molecular methods were applied to small cohorts of clinical samples from patients with urological malignancies, in an exploratory analysis. The molecular data was analysed in conjunction with clinical information to draw hypotheses on the biology and natural history of these cancer, and to suggest possible utility of mutDNA analysis in their clinical management. Some of the findings suggest areas of potential utility, which merit further validation or investigation in larger cohorts or clinical studies.
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Cortés, Hinojosa Marlies. "Role of ZEB1 in macrophages during homeostasis, inflammation and cancer." Doctoral thesis, Universitat de Barcelona, 2017. http://hdl.handle.net/10803/565913.
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ZEB1 is a transcription factor whose expression in cancer cells promotes tumor initiation and progression. In this study, we for the first time characterized Zeb1 and study its function in macrophages under either homeostasis or activation conditions as well as in a murine cancer model. We found that macrophages deficient for Zeb1 showed aberrant characteristics in phenotype and functions, under physiological and pathological conditions. Here we clarified a functional role of Zeb1 on macrophages playing a role in macrophage phagocytosis, migration and inflammation as well as in tumor progression in a non-cell-autonomous manner modulating the tumor microenviroment. In fact the evidence presented indicates that the downregulation of Zeb1 in macrophages is associated with the inhibition of TAM characteristics and inhibition of tumor progression.
ZEB1 plays important roles during embryogenesis and deletion of both alleles of Zeb1 in mice results in embryonic lethality. ZEB1 represses key genes involved in the terminal differentiation of multiple tissues, including inter alia epithelial cells, pituitary gland, skeletal and smooth muscle, cartilage, and bone. Although ZEB1 is expressed in lymphoid cells where it represses pivotal hematopoietic transcription factors, there was no evidence for a role of ZEB1 in the regulation of lymphoid or myeloid differentiation. We showed here that downregulation of Zeb1 in bone marrow precursors promoted their differentiation towards macrophages. These data further support a model, best characterized in epithelial tissues and skeletal muscle, where ZEB1 expression needs to decline for early precursors to terminally differentiate.
ZEB1 has been extensively characterized in cancer cells where it promotes their stemness, survival and invasiveness. However, its role in the tumor microenvironment remained to be elucidated. Among cancer cells, ZEB1 is not expressed across the entire tumor mass but is rather restricted to a subpopulation of stem-like malignant cells at the invasive front, actually, at the interface where cancer cells and TAMs interact. Although ZEB1 expression among stromal cells has been noted, the identity of the cell types expressing ZEB1 has not been established. This study showed that ZEB1 is also expressed in TAMs and that ZEB1 not only bilaterally regulates the crosstalk between cancer cells and TAMs but that this crosstalk regulates ZEB1 expression itself. Thus, Zeb1 was upregulated in macrophages that have interacted with cancer cells as well as in cancer cells that have interacted with wild-type TAMs. The tumor-promoting role of ZEB1 is therefore supported by a positive feedback of its expression between malignant cells and TAMs. We found that Zeb1 is restricted to the F4/80low macrophage/TAM subpopulation—previously known to display stronger pro-tumor and pro-angiogenic functions—whose share is expanded by ZEB1.
Soluble factors produced by the tumor—e.g., CSF1 and CCL2—attract F4/80low CCR2+ monocytes into their microenvironment where they are activated into TAMs. Inhibition of the CCL2–CCR2 axis blocks monocyte recruitment into the tumor stroma and inhibits tumor growth. We found that Zeb1 promotes monocyte migration both in response to chemotactic stimuli (CSF1 and CCL2) and in the context of cancer. Zeb1-deficient TAMs expressed lower levels of Ccr2 and were unable to induce Ccl2 in ID8 cells. At the same time, the maximum effect of ZEB1 as a biomarker of poorer prognosis in ovarian cancer patients depended on high levels of CCL2. These data establish Zeb1 as an important inducer of the pro-tumor and pro-metastatic CCR2-MMP9-CCL2 loop between tumor cells and TAMs.
It is important to note that this CCR2-MMP9-CCL2 loop was inhibited by just a partial downregulation of Zeb1 in TAMs. Data here showed that the pro-tumor role of ZEB1 in TAMs also depends on a similarly narrow threshold of expression. Zeb1 (+/-) macrophages still express about half of the Zeb1 mRNA levels of wild-type macrophages, but this downregulation was enough to render Zeb1 (+/-) TAMs unable to promote tumor growth when transplanted into tumor-bearing mice as wild-type macrophages did. As in the case of ZEB1 expression in cancer cells, to the best of our knowledge, this is the first example of a heterozygous gene deletion being sufficient to block the tumor-promoting role of TAMs.
Expression of ZEB1 in cancer cells has been associated to increased chemotherapy resistance. In parallel, we found here that expression of ZEB1 in TAMs also increased the cancer cell resistance to chemotherapy. In that line, we showed that Zeb1 in TAMs increased the expression of Il10, Mmp9 and Il1b—that have a suppressor effect on chemotherapy—and of the drug efflux transporter Mdr1. The dual role of ZEB1 promoting tumor progression in cancer cells and in TAMs—albeit through different mechanisms—has translational implications. Targeting ZEB1 in cancer cells is being considered in ongoing clinical trials but data here suggest that improving chemotherapy response would also require the downregulation of ZEB1 in TAMs. The fact that a partial downregulation of Zeb1 in TAMs was sufficient to abolish TAMs’ tumor-promoting function is highly relevant for therapy approaches aiming at blocking ZEB1 expression and/or function.
These results establish a new role for ZEB1 promoting tumor progression through its expression in TAMs, thus setting ZEB1 expression as a relevant target in cancer therapy.
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Sigalas, Iakovos. "Alternatively spliced forms of the mdm2 oncogen in human cancer." Thesis, University of Newcastle Upon Tyne, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309826.
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Lau, Kelvin Kar Wing. "Vascular targeting of anti-cancer therapy." Thesis, University of Oxford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311869.
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Buchanan, Cara F. "Shear Stress-Mediated Tumor-Endothelial Cross Talk Regulates the Angiogenic Potential of Breast Tumors In Vitro." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/50604.
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The structural and functional abnormalities of the tumor vasculature generate regions of elevated interstitial fluid pressure and aberrant flow shear stress within the tumor microenvironment. While research has shown that the hydrodynamics of the tumor vasculature reduce transport and uptake of therapeutic agents, the underlying mechanisms by which fluid forces regulate vascular organization are not well known. Understanding the reciprocal interaction between tumor and endothelial cells to mediate angiogenesis, and the role of flow shear stress on this process, may offer insight into the design of improved therapeutic strategies to control vascularized tumors. Instrumental to this is the development of physiologically relevant models that enable tumor-endothelial co-culture under dynamic conditions. By integrating tissue-engineering strategies with cancer biology, micro-scale fluid mechanics, and optical flow diagnostics, the goal of this research was to develop a 3D in vitro microfluidic culture model to investigate tumor-endothelial cross talk under physiologically relevant flow shear stress. This objective was motivated by early findings demonstrating a contact-independent, paracrine-mediated mechanism by which endothelial cells enhance tumor-expressed angiogenic factors during 2D, static co-culture. The 3D tumor vascular model consists of a central microchannel embedded within a type I collagen hydrogel, through which a range of normal (4 dyn/cm^2), low (1 dyn/cm^2) and high (10 dyn/cm^2) microvascular wall shear stresses (WSS) were introduced. Endothelial cells lining the microchannel lumen form a confluent endothelium across which soluble growth factors are exchanged with tumor cells in the gel. Microscopic particle image velocimetry ("-PIV) was integrated within the model to enable noninvasive optical measurement of velocity profiles and quantification of WSS, which were then correlated with angiogenic potential. Results demonstrate that endothelial permeability decreases as a function of increasing WSS, while co-culture with tumor cells increases permeability. This response is likely due to shear stress-mediated endothelial cell alignment and tumor-VEGF-induced permeability. In addition, high WSS (10 dyn/cm^2) significantly down-regulates tumor-expressed angiogenic factors, suggesting flow shear stress-mediates endothelial cross talk with surrounding tumor cells. Collectively, this research demonstrates the utility of the 3D in vitro microfluidic culture model as a versatile platform for elucidating the role of tumor-relevant hydrodynamic stress on cellular response.Ph. D.
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McKay, Judith A. "The expression of xenobiotic metabolising enzymes in human tumours." Thesis, University of Aberdeen, 1996. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU078740.
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The cytochromes P450 (CYPs), epoxide hydrolases (EHs) and glutathione S-transferases (GSTs) are three of the major families of enzymes involved in the metabolism of xenobiotics in the human body. Immunohistochemical analysis revealed a high frequency of expression of xenobiotic metabolising enzymes in all tumour types studied, in contrast to corresponding normal tissue which displayed only low levels of expression. Further examination of the CYP1 family was carried out by immunoblot analysis. All breast tumours studied were found to express CYP1B1, and not CYP1A1 or CYP1A2. Moreover, CYP1B1 was identified in a number of kidney tumours but not in corresponding normal kidney, indicating that CYP1B1 may be a tumour-specific form of CYP, RT-PCR, in combination with restriction digestion and DNA sequencing, was used to identify CYP mRNA species present in several tumour types. Although CYP1A1 mRNA was identified in breast carcinomas, CYP1B1 was found to be the most frequently expressed form of the CYP1 family in this tissue. CYP3A mRNA was also displayed by several breast tumours, and demonstrated by sequencing to be CYP3A5. A similar situation to breast tumours was observed in tumours of the gastro-intestinal and urinary tracts, with CYP1B1 being the most frequently expressed form of the CYP1 family, and only a small number of samples displaying evidence of CYP1A mRNA. The effects of the expression of xenobiotic metabolising enzymes in tumours may be complex, and depend upon the relative amounts of active protein present, but it is likely that they will exert an influence on both the development of carcinogenesis and the anti-cancer drug resistance of tumours.
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Hanna, Fahmy William Fahmy. "Calcitonin and related peptides in mammalian neuroendocrine tumours." Thesis, Queen's University Belfast, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295357.
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Onyesom, Ichioma. "Sirolimus liposomal formulations for targeting of cancer tumours." Thesis, University of Greenwich, 2014. http://gala.gre.ac.uk/13326/.
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In clinical trials, sirolimus (rapamycin, a macrocyclic lactone) has been shown to exhibit antitumor activity across a variety of human cancers by binding to and inhibiting the activation of the mammalian target of rapamycin (mTOR), thus preventing cell cycle progression from the G1 to S phase. Inhibitors of mTOR have received regulatory approval as immunosuppressive agents for the treatment of allograft rejection and as antitumor agents for kidney cancer (Rapamune®). In these clinical trials tumour cell proliferation was dramatically reduced without sirolimus being formulated in a drug carrier. The more challenging question is whether strategies can be developed to improve the delivery of sirolimus directly to tumour cells and maximize mTOR inhibition? The aim of the research reported herein was to develop, characterise and evaluate the anti-cancer activity of sirolimus loaded liposome formulations. Liposome-drug formulations were prepared using the thin film hydration method and were characterised using particle size analysis, atomic force icroscopy (AFM), differential scanning calorimetry (DSC) and X-ray photoelectron spectroscopy (XPS). The particle size analysis of the liposome formulations showed that the liposome-drug formulations were stable over a 6 month period of time. Further characterization of the liposome-drug formulations using XPS and DSC studies demonstrated the incorporation of the drug (sirolimus) in the liposome bilayer. In order to ascertain the anti-tumour activity of the sirolimus formulations, in-vitro studies using MTT assays were carried out on human breast cancer cell lines (MCF-7 and BT-474). The cytotoxicity studies using pure sirolimus showed anti-proliferative action at concentrations above 40 μg/mL and the formulated liposome formulations also demonstrated anti-proliferative effects when incubated with the cancer cells. Parameters such as lipid composition, incubation time and drug loading were established as important factors that play a key role in the therapeutic efficacy of the sirolimus loaded liposomes. Fluorescent images obtained from the cellular uptake and apoptosis studies also provided supporting data which demonstrated the anti-proliferative effect of the liposome formulations. In addition, sirolimus was designed to actively target breast cancer cells by conjugating transferrin on the surface of the sirolimus loaded liposomes. Both in-vitro and in-vivo studies of the conjugated sirolimus formulations demonstrated the formulation to be more effective in inducing anti-proliferative effects compared to the passive formulation (non-conjugated sirolimus loaded liposomes). Sirolimus loaded liposome anticancer activity towards prostate cancer cell lines (LNCAP and DU-145) has also been evaluated. Similar results to the breast cancer studies were obtained; specific parameters were also shown to influence the anti-proliferative efficacy of the sirolimus liposome formulations in prostate cancer cells.
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Lombardi, Ismael Augusto Silva [UNESP]. "Metilação e expressão do gene BRCA1 em meningiomas." Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/88064.
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lombardi_ias_me_botfm.pdf: 529927 bytes, checksum: 6cb4e1254a86d1683806ac3cb6ca21b7 (MD5)Meningiomas são os tumores intracranianos primários mais comuns e correlacionam-‐se com câncer de mama, compatilhando características como incidência maior no sexo feminino, receptores para hormônios sexuais e crescimento a exposição a hormônios sexuais. O gene BRCA1 é amplamente estudado no câncer de mama hereditário e esporádico, entretanto, são poucos os trabalhos que correlacionam BRCA1 e meningiomas. O BRCA1 é gene de supressão tumoral, interagindo com outros oncogenes, atuando no reparo do DNA durante a divisão celular e modulando negativamente receptores de estrógeno e progesterona. Avaliar o padrão de metilação de e expressão de BRCA1 em meningiomas e tecidos controles, e a expressão de receptores de estrógeno e progesterona em meningiomas e controles, correlacionando estes dados com dados epidemiológicos da casuística. Casuística e métodos: pacientes com diagnóstico de meningiomas tiveram amostras tumorais colhidas durante cirurgias de rotina pela disciplina de Neurocirurgia da Faculdade de Medicina de Botucatu (FMB) e do Hospital Mário Gatti, em Campinas. Previamente, o projeto foi aprovado pelo Comitê de Ética em Pesquisa e cada paciente concordou em participar ao assinar o Termo de Consentimento Livre e Esclarecido. Amostras controle de aracnóide foram colhidas de cadáveres no serviço de necropsia da disciplina de Patologia da FMB. As amostras tumorais foram avaliadas para metilação de BRCA1 por PCR específica para metilação e os resultados avaliados por eletroforese. A expressão foi avaliada por PCR em tempo real os resultados dados em relação a amostras comtroles. A expressão de receptores de estrógeno (RE) e progesterona (RP) foram analisadas por imuno-histoquímica, conforme rotina da disciplina de Patologia da FMB. Foram avaliados 50 meningiomas entre...
Meningiomas are the most common primary intracranial tumors and correlate with breast cancer, shearing features like higher incidence in female, sexual hormone receptors and growth to exposure to sexual hormones. The gene is widely studied in hereditary and sporadic breast cancer, however, there are few studies that correlate BRCA1 and meningiomas. The BRCA1 is a tumor suppressor gene and interacts with other oncogenes by DNA repairing during cell division and also negative modulating estrogen and progesterone receptors. To assess the pattern of methylation and expression of BRCA1 in meningiomas and control tissues, and the expression of estrogen and progesterone receptors in meningiomas and control tissues, and to correlate these data with patients epidemiological data. Patients diagnosed with meningioma had collected tumors samples during routine surgeries by the discipline of Neurosurgery in Faculty of Medicine of Botucatu (FMB) and Mario Gatti Hospital in Campinas. Previously, the project was approved by the Research Ethics Committee and each patient agreed to participate by signing the Instrument of Consent. Control arachnoid samples were collected from cadavers during routine of necropsy of Pathology departament in FMB. The tumor samples were analyzed for methylation of BRCA1 by methylation specific PCR and the results were evaluated by electrophoresis. The expression was assessed by real-‐time PCR results given in relation to samples comtroles. The expression of estrogen receptors (ER) and progesterone (PR) were analyzed by immunohistochemistry, as routine in Pathology departament. There were 50 meningiomas between January 2009 to September 2012, 22 male and 28 female. The methylation of BRCA1 in meningiomas was statistically significant compared to control tissues... (Complete abstract click electronic access below)
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Lombardi, Ismael Augusto Silva. "Metilação e expressão do gene BRCA1 em meningiomas /." Botucatu : [s.n.], 2013. http://hdl.handle.net/11449/88064.
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Orientador: Adriana Camargo FerrasiCoorientador: Maria Inês de Moura Campos Pardini
Coorientador: Marco Antonio Zanini
Banca: Carlos Gilberto Carlotti Junior
Banca: Eny Maria Goloni-Bertollo
Resumo: Meningiomas são os tumores intracranianos primários mais comuns e correlacionam-‐se com câncer de mama, compatilhando características como incidência maior no sexo feminino, receptores para hormônios sexuais e crescimento a exposição a hormônios sexuais. O gene BRCA1 é amplamente estudado no câncer de mama hereditário e esporádico, entretanto, são poucos os trabalhos que correlacionam BRCA1 e meningiomas. O BRCA1 é gene de supressão tumoral, interagindo com outros oncogenes, atuando no reparo do DNA durante a divisão celular e modulando negativamente receptores de estrógeno e progesterona. Avaliar o padrão de metilação de e expressão de BRCA1 em meningiomas e tecidos controles, e a expressão de receptores de estrógeno e progesterona em meningiomas e controles, correlacionando estes dados com dados epidemiológicos da casuística. Casuística e métodos: pacientes com diagnóstico de meningiomas tiveram amostras tumorais colhidas durante cirurgias de rotina pela disciplina de Neurocirurgia da Faculdade de Medicina de Botucatu (FMB) e do Hospital Mário Gatti, em Campinas. Previamente, o projeto foi aprovado pelo Comitê de Ética em Pesquisa e cada paciente concordou em participar ao assinar o Termo de Consentimento Livre e Esclarecido. Amostras controle de aracnóide foram colhidas de cadáveres no serviço de necropsia da disciplina de Patologia da FMB. As amostras tumorais foram avaliadas para metilação de BRCA1 por PCR específica para metilação e os resultados avaliados por eletroforese. A expressão foi avaliada por PCR em tempo real os resultados dados em relação a amostras comtroles. A expressão de receptores de estrógeno (RE) e progesterona (RP) foram analisadas por imuno-histoquímica, conforme rotina da disciplina de Patologia da FMB. Foram avaliados 50 meningiomas entre... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Meningiomas are the most common primary intracranial tumors and correlate with breast cancer, shearing features like higher incidence in female, sexual hormone receptors and growth to exposure to sexual hormones. The gene is widely studied in hereditary and sporadic breast cancer, however, there are few studies that correlate BRCA1 and meningiomas. The BRCA1 is a tumor suppressor gene and interacts with other oncogenes by DNA repairing during cell division and also negative modulating estrogen and progesterone receptors. To assess the pattern of methylation and expression of BRCA1 in meningiomas and control tissues, and the expression of estrogen and progesterone receptors in meningiomas and control tissues, and to correlate these data with patients epidemiological data. Patients diagnosed with meningioma had collected tumors samples during routine surgeries by the discipline of Neurosurgery in Faculty of Medicine of Botucatu (FMB) and Mario Gatti Hospital in Campinas. Previously, the project was approved by the Research Ethics Committee and each patient agreed to participate by signing the Instrument of Consent. Control arachnoid samples were collected from cadavers during routine of necropsy of Pathology departament in FMB. The tumor samples were analyzed for methylation of BRCA1 by methylation specific PCR and the results were evaluated by electrophoresis. The expression was assessed by real-‐time PCR results given in relation to samples comtroles. The expression of estrogen receptors (ER) and progesterone (PR) were analyzed by immunohistochemistry, as routine in Pathology departament. There were 50 meningiomas between January 2009 to September 2012, 22 male and 28 female. The methylation of BRCA1 in meningiomas was statistically significant compared to control tissues... (Complete abstract click electronic access below)
Mestre
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Kneubil, Maximiliano Cassilha. "Expressão de receptor de andrógeno em carcinoma mamário triplo negativo e sua correlação com fatores prognósticos." reponame:Repositório Institucional da UCS, 2015. https://repositorio.ucs.br/handle/11338/1167.
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Introdução: O câncer de mama é uma doença heterogênea e complexa. Carcinomas mamários triplo negativos (CMTN) são tumores com uma agressividade biológica intrínseca, resultando em um prognóstico desfavorável. O receptor de andrógeno (RA) é um dos marcadores mais estudados na atualidade em CMTN, estando associado com a gênese e desenvolvimento do câncer de mama. Objetivo: Correlacionar a expressão do RA em pacientes com CMTN com características clínicas e patológicas referentes à idade do paciente, Ki-67, grau histológico e infiltração intratumoral de linfócitos (IIL). Métodos: O estudo foi de delineamento transversal e retrospectivo, de todos os casos de CMTN registrados em uma instituição, entre janeiro de 2012 e maio de 2014. Os materiais histológicos dos tumores mamários foram submetidos ao estudo imunoistoquimico para RA, e foram correlacionados com as variáveis idade, grau histológico, IIL e Ki-67. A positividade para RA foi determinada com o anticorpo monoclonal RA 441. Quando o RA foi positivo, a expressão foi considerada fraca quando Escore-H≤150 e forte quando Escore-H>150. A análise da porcentagem de IIL foi realizada através de um corte do tumor emblocado em parafina e corado por hematoxilina e eosina (HE) e foi definida como a porcentagem de linfócitos em contato direto com células tumorais. Resultados: 34 CMTN foram analisados. A média da idade foi de 51,9 anos (variação 30-82 anos). Das 34 amostras, 23 casos (67,7%) foram RA-negativo e 11 casos (32,3%) foram RA-positivo. Dos casos positivos, a expressão foi considerada fraca em 6 casos e forte em 5 casos. A maioria dos pacientes (n=28, 82%) apresentaram tumores pouco diferenciados. A expressão média do Ki-67 foi 65% no grupo RA-negativo e 43,6% no grupo RA-positivo (p<0,05). Observou-se uma associação estatísticamente significante entre a variável idade e a expressão do RA (p<0,005), sendo a idade média de 70,8 anos no grupo RA fortemente positivo e 42,3 anos no grupo RA fracamente positivo. Não se observou associação estatística entre a expressão do RA e as variáveis grau histológico e IIL. A porcentagem média de IIL foi 38,6% no grupo RA-positivo e 39,1% no grupo RA-negativo (p=0,3). Conclusão: A expressão do RA em CMTN esteve associada a pacientes mais idosas e a tumores com menor expressão de Ki-67. A expressão do RA em pacientes com CMTN delinou 2 subgrupos com fenótipos distintos. No entanto, não houve associação entre expressão do RA com grau histológico e IIL.Submitted by Ana Guimarães Pereira (agpereir@ucs.br) on 2016-05-18T12:33:38Z No. of bitstreams: 1 Dissertacao Maximiliano Cassilha Kneubil.pdf: 1763051 bytes, checksum: 88341a89a73f5a6646d6652ecc0d5853 (MD5)
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Background: Breast cancer is a heterogeneous and complex disease. Triple Negative Breast Cancer (TNBC) are characterized by intrinsic aggressive tumour biology resulting in poor prognosis. Androgen Receptor (AR) is one of newly emerging biomarker in TNBC and has been demonstrated to play an important role in the genesis and in the development of breast cancer. Objective: In the present study, we explored the correlation of AR expression with age, Ki-67, histological subtype, histological grade and value of Tumor-Infiltrating Lymphocytes (TIL) in TNBC. Methods: We identified consecutive invasive TNBC from a cancer registry in a single institution between January 2012 and May 2014. The biopsies were analyzed by immunohistochemistry for AR and were correlated with age, histological grade, TIL and Ki-67. AR positivity was determined with clone AR 441 antibody. When AR was positive, the expression was considered weak when H-score≤150 and strong when Hscore> 150. The analysis of percentage of TIL was performed on a single full-face HEstained tumor section and TIL were defined as the percentage of lymphocytes in direct contact with the tumor cells. Results: 34 TNBC have been analyzed to date. The mean age was 51.9 years (range 30- 82). Of the 34 TNBC samples, 23 cases (67.7%) were AR-negative and 11 cases (32.3%) were AR-positive. Of the positive cases, the expression was weak in 6 cases and strong in 5 cases. Most patients (n=28, 82%) presented poorly differentiated tumors and all patients presented invasive ductal carcinoma. The mean expression of Ki67 was 65% in AR-negative group and 43.6% in AR-positive group, respectively (p<0.05). Older age was associated with AR expression, the mean age in AR strong expression was 70.8 years (p<0.005) compared to 42.3 years in group with AR weak expression. The AR expressions was not associated with histological grade and TIL. The mean of TIL was 38.6% in the AR-positive group and 39.1% in the AR-negative group (p=0.3). Conclusion: The present analysis showed that AR expressiveness in TNBC was associated with older patients and tumors with lower expression of Ki67. The expressiveness of AR in patients with TNBC through IHC outlined 2 subgroups with distinctive phenotypes. However, the expression of RA in patients with TNBC was not associated with the percentage of TIL and histological grade.
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Stewart, Trina Jane. "Adoptive immunotherapy studies of HPV16E7-expressing tumours /." St. Lucia, Qld, 2002. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16089.pdf.
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Schofield, James W. "Aspects of modelling solid tumours." Thesis, University of Oxford, 2010. http://ora.ox.ac.uk/objects/uuid:b7c50880-ed03-451e-9841-209f2de6a982.
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This thesis considers aspects of modelling solid tumours. We begin by considering the common assumption that nutrient or drug concentrations in avascular tumour spheroids are radially symmetric. We derive a simple Poisson equation for biomolecular diffusion into an avascular tumour, but with highly oscillatory boundary conditions due to the surrounding capillary network. We find that the assumption of radial symmetry is legitimate for biomolecules that are taken up in sufficient quantities by proliferating cancer cells; however radially symmetric profiles need not be observed otherwise. We then investigate how the gap between an avascular tumour and the neighbouring vasculature varies as the tumour grows. This is explored by (i) using scaling arguments based on ordinary differential equations, (ii) coupling the rate of oxygen flux from the vasculature to oxygen evolution within the tumour, and (iii) deriving a system of six coupled non-linear partial differential equations modelling the tumour evolution. It is found that as the tumour grows any initial gap between the tumour and neighbouring vasculature closes since there is no mechanism which would sufficiently up-regulate non-cancerous cell proliferation. This is in contrast to the intra-cornea implantation observations, upon which several mathematical models are based. Finally, we study the growth and treatment of a vascular tumour subjected to chemotherapies, particularly when the therapies can exhibit an anti-angiogenic effect and resistance to the therapy is incorporated. A multi-compartment model is derived for the evolution of a tumour undergoing treatment and parameters are estimated, with extensions to incorporate numerous different therapy protocols in the literature. We find that anti-angiogens can be effective, though the appropriate scheduling is counter-intuative and contradicts many standard therapy rules. We conclude that chemotherapy protocol design is very sensitive to the mode of action of the drug and simple general strategies will, in many cases, not be the most effective.
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Anderson, William John. "Molecular characterisation of rhabdomyosarcoma." Thesis, Institute of Cancer Research (University Of London), 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312950.
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Borges, Pinto Lais Izabel. "Alu-polymerase chain reaction genomic fingerprinting in neuroblastoma." Thesis, University of Newcastle Upon Tyne, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366679.
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Barreta, Amilcar 1980. "Laparoscopia na abordagem inicial de tumores anexiais = Laparoscopy for diagnosis and treatment of adnexal tumors." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/312141.
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Orientadores: Sophie Françoise Mauricette Derchain, Joana Fróes Bragança BastosDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
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Resumo: Introdução: O câncer de ovário é o sétimo câncer mais comum em mulheres. A sensibilidade e especificidade dos exames laboratoriais e de imagem não são adequadas para o diagnóstico de câncer de ovário. Atualmente o padrão-ouro para o diagnóstico do câncer de ovário é o exame histopatológico em parafina. Por este motivo, aproximadamente 10% das mulheres terão que ser operadas devido a um tumor anexial durante sua vida. A laparoscopia é comumente usada na tentativa de reduzir a morbidade cirúrgica nestes casos. Objetivo: Avaliar as diferenças nas características clínicas, no diagnóstico histopatológico, na duração da cirurgia e na incidência de complicações cirúrgicas em mulheres submetidas à laparoscopia e à laparotomia para diagnóstico e tratamento de tumores anexiais, e avaliar os fatores associados à falha da laparoscopia (conversão à laparotomia). Sujeitos e métodos: Para este estudo prospectivo foram convidadas a participar 210 mulheres com tumor anexial, dentre as quais foram incluídas 133 mulheres com indicação cirúrgica. Oitenta e oito mulheres foram submetidas à laparotomia e 45 foram submetidas à laparoscopia. Catorze das 45 laparoscopias foram convertidas à laparotomia durante o procedimento cirúrgico. Foi avaliado se idade, índice de massa corpórea (IMC), número de cirurgias abdominais prévias, níveis do marcador tumoral CA-125, valores do Índice de Risco de Malignidade (IRM), maior diâmetro do tumor, diagnóstico histopatológico, duração da cirurgia e número de complicações cirúrgicas diferiram entre o grupo de mulheres submetidas à laparoscopia e o grupo submetido à laparotomia, e se estes fatores estiveram associados à conversão da laparoscopia em laparotomia. Foram também avaliados os motivos intraoperatórios para conversão da laparoscopia em laparotomia conforme relatado pelos cirurgiões nos registros cirúrgicos. Resultados: A prevalência de tumores malignos neste estudo foi de 30%. Os níveis do CA-125, os valores do IRM, o maior diâmetro do tumor e a duração da cirurgia foram maiores no grupo da laparotomia que no grupo da laparoscopia. A incidência de complicações foi similar quando comparados os grupos de laparotomia e laparoscopia e quando comparados os grupos de laparoscopias bem sucedidas com o grupo de laparoscopias convertidas à laparotomia. Quando foram analisadas mulheres com tumores anexiais benignos, a incidência de complicações foi menor no grupo da laparoscopia quando comparado ao grupo da laparotomia. Os fatores associados à falha da laparoscopia (conversão à laparotomia) foram o maior diâmetro do tumor e a presença de tumor maligno. Durante a laparoscopia, os principais motivos relatados nos registros cirúrgicos como causa de conversão em laparotomia foram: o diâmetro do tumor e a presença de aderências peritoneais. Conclusões: Este estudo sugere que o diâmetro do tumor, a presença de aderências peritoneais e a presença de um tumor maligno são as principais causas de conversão de uma laparoscopia em laparotomia. A conversão, entretanto, não aumenta a incidência de complicações cirúrgicas
Abstract: Introduction: Ovarian cancer is the seventh most common cancer in women. Imaging and laboratorial exams do not have adequate sensitivity and specificity to diagnose adnexal cancer. The gold-standard for adnexal cancer diagnose is the histopathological exam at paraffin section. For this reason about 10% of the women will have to be operated by an adnexal tumor during their lifetime. Laparoscopy is frequently used to reduce surgical morbidity at those cases. Objective: To assess the differences in clinical factors, histopathologic diagnose, operative time and complication rates between women undergoing laparoscopy or laparotomy to diagnose and treat an adnexal mass and to evaluate the factors that are associated with laparoscopy failure and conversion to laparotomy. Subjects and methods: In this prospective study, 210 women were invited to participate, of which 133 women with adnexal masses were included. Eighty-eight women underwent laparotomy and 45 women underwent laparoscopy. Fourteen of the 45 laparoscopies were further converted to laparotomy during the surgical procedure. We assessed whether age, body mass index (BMI), previous abdominal surgeries, CA-125 levels, Index of Risk of Malignancy (IRM), tumor diameter, histological diagnose, operative time and surgical complication rates differed from laparoscopy to laparotomy group and whether those factors were associated with conversion of laparoscopy to laparotomy. We also assessed surgical logs to evaluate the intraoperative reasons, as stated by the surgeons, to convert a previously indicated laparoscopy to laparotomy. Results: 30% of women at our study had malignant tumors. CA-125 levels, IRM values, tumor diameter and operative times were higher for the laparotomy group compared to the laparoscopy group. Complication rates were similar for the laparoscopy and laparotomy groups and also for successful laparoscopy and laparoscopy converted to laparotomy groups. Surgical complication rate in women with benign tumors was lower for the laparoscopy group compared to that for the laparotomy group. The clinical factors associated with laparoscopy failure (conversion to laparotomy) were the largest tumor diameter and malignancy. During laparoscopy, adhesions and the largest tumor diameter were the principal factors reported as causes of conversion. Conclusions: This study suggests that tumor diameter, peritoneal adhesions and the presence of a malignant tumor were the principal causes of laparoscopy conversion to laparotomy. However the conversion did not increase complication rates
Mestrado
Oncologia Ginecológica e Mamária
Mestre em Ciências da Saúde
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Marits, Per. "On CD4+ T Lymphocytes in Solid Tumours." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8325.
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Custódio, Aline Cadurin. "Avaliação molecular do gene supressor de tumor PTEN em tumores do sistema nervoso." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/17/17135/tde-11062013-150806/.
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O câncer é uma doença potencialmente letal. Os tumores se desenvolvem em células que estão se dividindo. Sua iniciação ou progressão está associada com o acúmulo de alterações genéticas. Essas alterações podem ser aberrações cromossômicas, mutações, polimorfismos e modificações epigenéticas. O câncer se desenvolve quando mecanismos de defesa do organismo sofrem alterações. Os tumores do sistema nervoso representam aproximadamente 2% de todos os tipos de câncer. O papel central do sistema nervoso e as conseqüências funcionais da perda de neurônios podem explicar a severidade dos tumores cerebrais. A formação dos tumores do cérebro humano é um processo complexo, envolvendo um acúmulo de alterações genéticas. Os genes supressores de tumor estão envolvidos na formação de tumores. Sua perda, inativação ou disfunção leva a célula a se dividir desordenadamente, surgindo assim tumores e neoplasias no local onde elas ocorrem. O objetivo deste trabalho foi fazer uma triagem de ocorrência de polimorfismos conformacionais no gene supressor de tumor PTEN em 50 amostras de tumores de Sistema Nervoso. Nenhuma alteração mutacional foi encontrada. Nossos resultados se assemelham aos da literatura em relação à ausência de alterações no gene PTEN em tumores benignos; em relação aos glioblastomas, a literatura cita uma alta freqüência de alterações no gene PTEN, mas não encontramos nenhuma alteração nas 9 amostras estudadas. Outro mecanismo como por exemplo a metilação da região promotora, poderia estar envolvido na inativação desse gene nos tumores analisados.Cancer is a potentially lethal illness. Tumors develop in cells that are dividing. Its initiation or progression is associated with the accumulation of genetic alterations. These alterations can be chromosome aberrations, mutations, polimorphisms and epigenetic modifications. The cancer develops when mechanisms of defence of the organism are altered. The tumors of the nervous system represent approximately 2% of all the types of cancer. The central role of the nervous system and the functional consequences of the loss of neurons can explain the severity of the cerebral tumors. The formation of the tumors of the human brain is a complex process, involving an accumulation of genetic alterations. The tumor suppressor genes are involved in the formation of tumors. If there is a loss, inactivation or disfunction, the cell will divide disorderly, and tumors and other neoplasias will appear in the place where they occur. The objective of this work was to make a selection of the occurrence of conformacional polymorphisms in the tumor suppresor gene PTEN in 50 samples of tumors of Nervous System. No mutacional alteration was found. Our results if are similar to the ones of the literature in relation to the absence of alterations in gene PTEN in benign tumors; in relation to glioblastomas, literature cites a high frequency of alterations in gene PTEN, but we did not find any alteration in the 9 studied samples. Another mechanism as, for example, the metilation of the promoterl region, could be involved in the inativação of this gene in the analyzed tumors.
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Barton, Rachael. "Isolation and characterisation of the ovarian cancer antigen CA125 and the development of gene directed enzyme prodrug therapy for the treatment of ovarian cancer." Thesis, University of Oxford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275193.
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Mokdsi, George. "Antitumour Metallocenes." University of Sydney. Chemistry, 2000. http://hdl.handle.net/2123/794.
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This thesis reports a study of the chemical stability and coordination chemistry of several antitumour metallocenes Cp2MCl2 (Cp = h5-C5H5; M = Ti 1, V 2, Nb 3, Mo 4), as well as derivatives of Cp2TiCl2 1, with nucleic acids, nucleic acid constituents and proteins. These studies were carried out in order to identify the biologically active species and more fully understand the molecular level mechanism of action of the antitumour metallocenes, in particular Cp2TiCl2 1, which is currently undergoing phase II clinical trials. The interactions of Cp2MoCl2 4 with four oligonucleotides were studied by 1H and 31P NMR spectroscopy. In 50 mM salt solutions of Cp2MoCl2 4, hydrolysis of the halide ligands occurred to give a solution with pD -2, containing a species in which both Cp rings remain metal bound for 24 h. At pD -7, partial hydrolysis of the Cp rings (-30percent) occurred after 24 h. Addition of an aqueous solution of Cp2MoCl2 4 in 50 mM salt to the self-complementary sequence d(CGCATATGCG)2, maintaining the pD at 6.0-7.0, showed no evidence for the formation of a metallocene-oligonucleotide complex and only peaks arising from hydrolysis of Cp2MoCl2 4 were detected. A similar result was obtained in titration experiments with the single stranded sequence d(ATGGTA) at pD 6.5-7.0. However, at pD 3.0, new signals assigned to a molybdocene-oligonucleotide complex(es), which was stable for hours at pD 3.0, were detected; while at pD -7 the complex is destabilised and only peaks arising from hydrolysis of Cp2MoCl2 4 were detected. Titration experiments at low pD with Cp2MoCl2 4 and the dinucleotide dCG were consistent with formation of a complex arising due to coordination of molybdenum to guanine N7 and/or cytosine N3. The results obtained showed that stable oligonucleotide adducts were not formed in 50 mM salt at pD -7 and hence it is highly unlikely that formation of molybdocene-DNA adducts in vivo is the primary action that is responsible for the antitumour properties of Cp2MoCl2 4. The rate of hydrolysis of the aromatic rings of Cp2TiX2 (X equals Cl 1, OCOCH2NH3Cl 27) and the dimethylsubstituted derivatives (MeCp)2TiX2 (X equals Cl 34, OCOCH2NH3Cl 41), in aqueous solutions at pD 2-8 was studied by 1H NMR spectroscopy. Rapid hydrolysis of both the halide/glycine and Cp ligands in Cp2TiX2 (X equals Cl 1, OCOCH2NH3Cl 27) occurred and predominantly gave a precipitate at pD -7. In contrast, under the same experimental conditions, the predominant species present in aqueous solutions of (MeCp)2TiX2 (X equals Cl 34, OCOCH2NH3Cl 41) at pH 2-8 contained both MeCp rings metal bound. At pD < 5, Cp2TiX2 (X equals Cl 1, OCOCH2NH3Cl 27) and (MeCp)2TiX2 (X equals Cl 34, OCOCH2NH3Cl 41) formed similar complex(es) with purine nucleotides. However, at pD >5, stable adducts between nucleotides and Cp2TiX2 (X equals Cl 1, OCOCH2NH3Cl 27) were not formed. In contrast, (MeCp)2TiX2 (X equals Cl 34, OCOCH2NH3Cl 41) formed complex(es) with 5'-dAMP or 5'-dGMP, which were stable for 24 h. These results suggest that formation of stable chelates between (MeCp)2TiX2 (X equals Cl 34, OCOCH2NH3Cl 41) and nucleic acid constituents in vivo is possible. However, the methyl substituted derivatives 34 and 41 did not show any antitumour activity against EAT in mice when administered in either 10percentDMSO/90percentsaline or in water at pH 6.2-6.4, which suggests that the labile Cp-Ti bond present in Cp2TiCl2 1 is required for antitumour activity. The synthesis of a range of Cp substituted titanocene derivatives was investigated in an attempt to prepare derivatives with modified Cp stability in comparison to the methyl substituted derivatives. The synthesis of derivatives (CpCH2Y)2TiCl2 where Y equals ?CHO 43, ?CONMe2 44, ?NO2 45, (RCp)2TiCl2 where R equals ?COMe 46, ?COOMe 47 or ?CONMe2 48, (CpNMe2)2TiCl2 62 and (Cp(CH2)2NMe2)2TiCl2 63 was unsuccessful, due to the presence of coordinating substituents on the Cp rings and poor stability in polar, protic solvents. Hence, these derivatives were excluded from further studies. The rate of hydrolysis of the Cp rings of Cp2TiX2 (X equals Cl 1, OCOCCl3 22 and OCOCH2NH3Cl 27) in aqueous solutions, 10percentDMSO/90percentD2O and 100percent DMSO was monitored by 1H NMR spectroscopy. Rapid hydrolysis of both the carboxylate and Cp ligands of Cp2TiX2 (OCOCCl3 22 and OCOCH2NH3Cl 27) occurred in DMSO to give biologically inactive species. The rate of these reactions were concentration dependent as dilution of these samples with saline or water to give the therapeutic conditions of 10percentDMSO/90percentD2O slowed the hydrolysis chemistry. In contrast, samples of Cp2TiX2 (X equals Cl 1 and OCOCH2NH3Cl 27) dissolved in water, gave solutions containing the presumed antitumour active species in which the halide or glycine ligands have been hydrolysed but the Cp rings remain metal bound. Thus, charged X ligands may be incorporated into Cp2TiX2 and will give comparable activity to Cp2TiCl2 1 provided the samples are administered in water. The antitumour metallocenes Cp2MCl2 (M equals Ti 1, V 2, Nb 3, Mo 4) and the inactive derivative (MeCp)2TiCl2 34 were found to inhibit the relaxation of supercoiled plasmid DNA pBR322 by human topoisomerase II in vitro. These results implicated the inhibition of topoisomerase II in the mechanism of antitumour activity although there was no direct correlation between the in vitro results with biological activity against EAT in vivo. UV spectroscopy confirmed that the metallocenes Cp2MCl2 (M equals Ti 1, Mo 4) became associated with and were stabilised to hydrolysis by calf thymus DNA but not with human serum albumin. ICP-AES was used to measure the amount of metal associated with either DNA or human serum albumin after incubation with Cp2MCl2 (M equals Ti 1, Nb 3, Mo 4) and dialysis of these solution. The results confirmed that DNA stabilises or becomes associated with the metallocenes. However, errors associated with the ICP-AES measurements did not allow these results to be quantified. 1H NMR spectroscopy was used to show that the antitumour metallocene Cp2MoCl2 4 formed an adduct with glutathione 72 in the pH range 3-7 through the sulfur donor group. In comparison, the antitumour metallocenes Cp2MCl2 (M equals Ti 1, Nb 3) showed limited adduct formation with glutathione 72 at pH -3 and no adducts were detected at pH > 5.5.
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Graham, Alastair Noel John. "An investigation into the factors promoting metastasis in non-small cell lung cancer." Thesis, Queen's University Belfast, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326409.
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Delgado, San Martin Juan A. "Mathematical models for preclinical heterogeneous cancers." Thesis, University of Aberdeen, 2016. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=230139.
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Cancer is a deadly, complex disease with 14 million new cases diagnosed every year and the endeavour to develop a cure is a global multidisciplinary effort. The complexity of cancer and the resulting vast volume of data derived from its research necessitates a robust and cutting-edge system of mathematical and statistical modelling. This thesis proposes novel mathematical models of quantification and modelling applied to heterogeneous preclinical cancers, focusing on the translation of animal studies into patients with particular emphasis on tumour stroma. The first section of this thesis (quantification) will present different techniques of extracting and quantifying data from bioanalytical assays. The overall aim will be to present and discuss potential methods of obtaining data regarding tumour volume, stromal morphology, stromal heterogeneity, and oxygen distribution. Firstly, a 3D scanning technique will be discusses. This technique aims to assess tumour volume in mice more precisely than the current favoured method (callipers) and record any cutaneous symptoms as well, with the potential to revolutionise tumour growth analysis. Secondly, a series of image processing methods will be presented which, when applied to tumour histopathology, demonstrate that tumour stromal morphology and its microenvironment play a key role in tumour physiology. Lastly, it will be demonstrated through the integration of in-vitro data from various sources that oxygen and nutrient distribution in tumours is very irregular, creating metabolic niches with distinct physiologies within a single tumour. Tumour volume, oxygen, and stroma are the three aspects central to the successful modelling of tumour drug responses over time. The second section of this thesis (modelling) will feature a mathematical oxygen-driven model - utilising 38 cell lines and 5 patient-derived animal models - that aims to demonstrate the relationship between homogeneous oxygen distribution and preclinical tumour growth. Finally, all concepts discussed will be merged into a computational tumour-stroma model. This cellular automaton (stochastic) model will demonstrate that tumour stroma plays a key role in tumour growth and has both positive (at a molecular level) and negative (at both a molecular and tissue level) effects on cancers. This thesis contains a useful set of algorithms to help visualise, quantify, and understand tissue phenomena in cancer physiology, as well as providing a series of platforms to predict tumour outcome in the preclinical setting with clinical relevance.
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Naylor, Michael Stuart. "Tumour necrosis factor and ovarian cancer." Thesis, Open University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.332896.
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Lunardi, Serena. "Tumour-stroma interaction in pancreatic cancer." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:8cb21185-38ab-40ae-8f12-2b52cc61a988.
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Pancreatic ductal adenocarcinoma (PDAC) is characterised by an abundant desmoplastic reaction driven by pancreatic stellate cells (PSCs). There is accumulating evidence that PSCs influence the malignant phenotype of PDAC. The aim of this study was to analyse the tumour response to radiation treatment in the presence of PSCs and to investigate the cytokine network in the coculture of PSCs and pancreatic cancer cells (PCCs). PSCs were used in coculture with different PCC lines. Clonogenic survival assays of several PCC lines cocultured with PSCs showed decreased radiosensitivity. This effect was abrogated by inhibition of the β1-integrin/FAK signalling pathway. Furthermore, tumour regrowth experiments after irradiation showed that coinjected PSCs were radioprotective for PCCs after single-dose and fractionated irradiation in xenografts. In addition, we examined the expression of 50 proteins in the supernatants of PCCs and PSCs in mono- and coculture conditions. The detected cytokine expression profile of PSCs included many proinflammatory factors. Also, we identified IP-10 as the chemokine with the highest differential upregulation in PSCs by paracrine stimuli from five different PCC lines. Human PDAC with a high stroma component had elevated IP-10 mRNA expression. IP-10 did not stimulate tumour cell growth and migration in our conditions even though several PCCs expressed its cognate receptor CXCR3. Nevertheless, we discovered that in human PDAC samples IP-10 and CXCR3 mRNA levels correlated with the presence of CD3ε, CD4, FoxP3, CTLA4 and CD39 used as surrogate markers for T regulatory cells (Tregs), known to exert an immunosuppressive effect. In conclusion, these data demonstrate that PSCs enhance survival of PCCs to radiation by activating β1-integrin/FAK signalling. Furthermore, the interaction between the tumour stroma in pancreatic cancer may support an immunosuppression by chemoattraction of Tregs following upregulation of IP-10. Further characterisation of the paracrine signalling between PCCs, PSCs and immune cells will improve the understanding of pancreatic cancer biology and could lead to the identification of new targets for multimodal therapy.
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Hollows, Robert John. "Using data from the cancer genome atlas to analyse DNA methylation and copy number changes in the Y chromosome in male cancers." Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7266/.
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Many human cancers are more prevalent in men than women. This disparity is not fully explained by differences in key risk factor exposures, which suggests a possible genetic cause. Recent research has reported a link between loss of the Y chromosome (LoY) and increased incidence of non-haematological cancers. Using data from The Cancer Genome Atlas, I conducted an integrated, multi-‘omic analysis of Y chromosome methylation and copy number aberrations in three different cancers – colon, head and neck and kidney. My results indicate that aberrant methylation of the Y chromosome is common in all three cancer types. Hyper-methylation occurs in short, discrete regions, interspersed among wider regions of more general hypo-methylation. I also show that LoY is the most common aneuploidy in all three cancers, affecting between one third and one half of patients. Furthermore, both aberrant methylation and LoY are associated with reduced expression of potentially important genes. Most interestingly, for HPV negative head and neck cancer patients, I show a statistically significant association between LoY and worse survival, and that LoY may be linked to smoking. Subject to further validation, this suggests that LoY could be important in the pathogenesis of head and neck cancer for HPV negative patients.
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Blacking, Thalia Margaret. "Investigating the cancer stem cell hypothesis in canine tumours." Thesis, University of Edinburgh, 2011. http://hdl.handle.net/1842/5563.
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The cancer stem cell hypothesis has recently re-emerged as a compelling paradigm for the development and progression of neoplastic disease. The hypothesis proposes that a specific subset of “cancer stem cells” (CSC), believed to share many features with normal stem cells, is exclusively responsible for maintaining tumour growth and driving progression. If the CSC hypothesis applies, it may require re-evaluation of the clinical approach to neoplasia. Spontaneous cancer in the domestic dog represents a significant welfare problem, with dogs developing many tumours strongly reminiscent of those affecting humans. This study sought to investigate whether cells with characteristics of CSC are identifiable in canine cancer. Assays to identify, isolate and characterise CSC were adapted to the canine system, and cancer cell lines and spontaneous tumours of diverse origin evaluated for the presence of candidate populations. Whilst analysis of surface expression patterns did not identify specific subpopulations within canine cancer cell lines, these were detectable in cells derived directly from primary tumours. Assays for stem cellassociated drug resistance mechanisms could also be used to identify subsets of putative canine CSC. Formation of “tumourspheres” by canine cancer cell lines was found to be highly density-dependent, so a potentially unreliable method of isolating CSC. Expression of the cell surface glycoprotein CD44 was associated with cellular proliferation status, although it may not represent a stable canine CSC marker. The NFκB survival pathway, associated with apoptosis resistance of some putative CSC, was constitutively active in canine cancer cell lines; suppression using specific inhibitors could reduce cell viability, indicating that this may represent a rational therapeutic target. Overall, these studies demonstrated that CSC assays may be adapted to the canine model system, although they require rigorous interrogation to distinguish apparent CSC attributes from basic biological properties. Cell lines have provided a stable background upon which to optimise assays, but appear less likely to demonstrate discrete CSC subpopulations. Putative CSC subsets may be more readily identifiable within heterogeneous primary tumour cells. The application of some of these adapted assays within a clinical setting may enable further characterisation of individual patients’ tumours, and inform therapeutic regimes for improved treatment outcomes.
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Tut, Vivienne Mai. "Cyclins A and D1 in human bladder cancer and their relationship to cell proliferation." Thesis, University of Newcastle Upon Tyne, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391399.
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