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Articles de revues sur le sujet "Ts polymorphism"
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Kim, Jung Oh, Han Sung Park, Eun Ju Ko, Jung Hoon Sung, Jinkwon Kim, Seung Hun Oh, Ok Joon Kim et Nam Keun Kim. « The 3′-UTR Polymorphisms in the Thymidylate Synthase (TS) Gene Associated with the Risk of Ischemic Stroke and Silent Brain Infarction ». Journal of Personalized Medicine 11, no 3 (12 mars 2021) : 200. http://dx.doi.org/10.3390/jpm11030200.
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Thymidylate synthase (TS) is a key gene involved in the repair of DNA damage and DNA synthesis that plays an important role in vascular development and recovery. In particular, TS gene polymorphisms play a major role in the progression of vascular disease and cancer metastasis. Therefore, the aim of this study was to investigate the association of three TS polymorphisms (1100T>C [rs699517], 1170A>G [rs2790], and 1494ins/del [rs151264360]) with ischemic stroke and silent brain infarction (SBI) in Koreans. A total of 1299 participants (507 stroke patients, 383 SBI patients, and 409 controls) were enrolled in the study. Genotyping of the three TS polymorphisms was performed by polymerase chain reaction-restriction fragment length polymorphism analysis. To examine the association between TS gene polymorphisms and the diseases, we performed statistical analyses, including multivariable logistic regression and Fisher’s exact tests. We found that TS 1100T>C and 1170A>G genotypes were strongly associated with ischemic stroke and SBI susceptibility. More specifically, the TS 1100T>C polymorphism was associated with the likelihood of ischemic stroke (TT vs. CC: AOR = 2.151, 95% CI = 1.275–3.628, P = 0.004) and SBI (TT vs. TC+CC: AOR = 1.443, 95 % CI = 1.009–2.063, P = 0.045). In contrast, the TS 1170A > G polymorphism exhibited lower correlation with the risk of stroke (AA vs. GG: AOR = 0.284, 95% CI = 0.151–0.537, P < 0.0001) and SBI (AA vs. GG: AOR = 0.070, 95% CI = 0.016–0.298, P = 0.0002). Furthermore, we confirmed that the TS 1100T>C polymorphism was synergistic with low folic acid levels (AOR = 6.749, P < 0.0001). Altogether, these results suggest that TS 1100T>C and 1170A > G polymorphisms are associated with the risk of ischemic stroke and SBI, and our study provides the first evidence that 3′-UTR variants in TS are potential biomarkers in ischemic stroke and SBI.
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Villafranca, Elena, Yury Okruzhnov, Miguel A. Dominguez, Jesús García-Foncillas, Ignacio Azinovic, Enrique Martínez, Jose J. Illarramendi et al. « Polymorphisms of the Repeated Sequences in the Enhancer Region of the Thymidylate Synthase Gene Promoter May Predict Downstaging After Preoperative Chemoradiation in Rectal Cancer ». Journal of Clinical Oncology 19, no 6 (15 mars 2001) : 1779–86. http://dx.doi.org/10.1200/jco.2001.19.6.1779.
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PURPOSE: Thymidylate synthase (TS) is an important target enzyme for the fluoropyrimidines. TS gene promoter possesses regulatory tandemly repeated (TR) sequences that are polymorphic in humans, depending on ethnic factors. These polymorphisms have been reported to influence TS expression. TS expression levels affect tumor downstaging after preoperative fluoruracil (5-FU)–based chemoradiation. Tumor downstaging correlates with improved local control and disease-free survival. The aim of this study is to correlate TR polymorphisms with downstaging and disease-free survival. PATIENTS AND METHODS: Sixty-five patients with rectal cancer underwent tumor resection after preoperative 5-FU–based chemoradiation. Tumor downstaging was evaluated by comparing the pretreatment T stage with the pathologic stage observed in the surgical specimen. TS polymorphism genotype was determined by polymerase chain reaction amplification of the corresponding TS promoter region, and products of amplification were electrophoresed, obtaining products of 220 bp (2/2), 248 bp (3/3), or both (2/3). The TS polymorphism genotype results were subsequently compared with the downstaging observed and with disease-free survival. RESULTS: Patients who were homozygous for triple TR (3/3) had a lower probability of downstaging than patients who were homozygous with double TR or heterozygous patients (2/2 and 2/3): 22% versus 60% (P = .036; logistic regression). Furthermore, a trend toward improved 3-year disease-free survival was detected in the 2/2 and 2/3 groups, compared with that in the 3/3 group (81% v 41%; P = .17). CONCLUSION: This preliminary study suggests that TS repetitive-sequence polymorphisms are predictive for tumor downstaging. TR sequences in TS promoter may be useful as a novel means of predicting response to preoperative 5-FU–based chemoradiation.
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Ugrasena, I. Dewa Gede, Harianto Notopuro, Subijanto Marto Sudarmo, Ketut Sudiana, Djajadiman Gatot et Ponpon Idjradinata. « MTHFR C677T and TS 5’-UTR 3R/3R Gene Polymorphism in Methotrexate-Resistant Childhood Acute Lymphoblastic Leukemia ». Indonesian Biomedical Journal 12, no 2 (29 juin 2020) : 177–82. http://dx.doi.org/10.18585/inabj.v12i2.1109.
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BACKGROUND: Childhood acute lymphoblastic leukemia (ALL) is the most common pediatric malignancy in Indonesia and often treated by methotrexate (MTX). Though it can be cured in 30-60% of patients, MTX resistance remains the major cause of treatment failure in childhood ALL. Previous sudies showed that its anti-leukemic property was moderated by MTX ability to inhibitmethylene tetra hydrofolate reductase (MTHFR) and thymidylate synthase (TS) in folate metabolism. This study investigates the correlation between MTHFR and TS polymorphism and MTX resistance in ALL children.METHODS: A total of 155 subjects obtained from all subjects prior to chemotherapy. DNA from blood samples were extracted and underwent polymerase chain reactionrestriction fragment length polymorphism (PCR-RFLP) to evaluate MTHFR C677T and TS 5’-UTR 3R/3R polymorphism.RESULTS: There was significant correlation between MTHFR C677T and TS 5’-UTR 3R/3R gene polymorphism with MTX resistance. Subjectswith MTHFR C677T and TS 5’-UTR 3R/3R gene polymorphism were 4 times (p=0.007) and 6.4 times (p=0.001) more likely to be MTX resistant than those without gene polymorphisms, respectively.CONCLUSION: MTHFR C677T andTS 5’-UTR 3R/3R represent dominant gene polymorphism related to MTX resistance in childhood ALL.KEYWORDS: gene polymorphism, folate metabolism, acute lymphoblastic leukemia
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Chen, Jin-Yin, He-Jian Chen et Pei-Feng Chen. « Association of expression and genotypes of thymidylate synthase in non-small cell lung cancer patients with different clinicopathological characteristics ». Pteridines 32, no 1 (1 janvier 2021) : 39–47. http://dx.doi.org/10.1515/pteridines-2020-0013.
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Abstract Objective To explore the expression and genotypes of thymidylate synthase (TS) in patients of non-small cell lung cancer (NSCLC) with different clinicopathological characteristics. Methods The expression profiles of TS were examined by immunohistochemical staining and quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) in 160 patients with NSCLC. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to detect TS-5′UTR tandem repeats, G/C nucleotide polymorphisms, and 3′UTR 6 bp deletion/insertion polymorphisms. The relationships between clinicopathological characteristics and TS expression or genotypes were investigated through χ 2 test. Kaplan–Meier survival analysis was used to analyze the association between TS expression and overall survival (OS) and disease-free survival (DFS) of NSCLC patients. Results The expression levels of TS protein and TS gene in NSCLC tissues were significantly higher than that in paracancerous tissues (P < 0.05). Furthermore, high expression of TS protein and 5′UTR polymorphism of TS gene showed significant correlation with differentiation, TNM stage, and lymph node metastases. The frequency of −6 bp/−6 bp genotypes in patients with NSCLC was 43.13% (69/160), which was higher than others. In addition, the rate of TS protein overexpression in NSCLC patients with 3R/3R was 79.79%, which was higher than others. Interestingly, high expression of TS protein predicted shorter DFS and OS and lower 3-year DFS rate and 3-year OS rate. Conclusions The expression levels of TS in NSCLC were significantly increased and may help to predict the prognosis of NSCLC, and high expression of TS protein and 5′UTR polymorphism of TS gene were significantly related to differentiation, TNM stage, and lymph node metastases.
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Fariña-Sarasqueta, A., M. J. E. M. Gosens, E. Moerland, I. van Lijnschoten, V. E. P. P. Lemmens, G. D. Slooter, H. J. T. Rutten et A. J. C. van den Brule. « TS Gene Polymorphisms Are Not Good Markers of Response to 5-FU Therapy in Stage III Colon Cancer Patients ». Analytical Cellular Pathology 33, no 1 (2010) : 1–11. http://dx.doi.org/10.1155/2010/731873.
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Aim: Although the predictive and prognostic value of thymidylate synthase (TS) expression and gene polymorphism in colon cancer has been widely studied, the results are inconclusive probably because of methodological differences. With this study, we aimed to elucidate the role of TS gene polymorphisms genotyping in therapy response in stage III colon carcinoma patients treated with 5-FU adjuvant chemotherapy.Patients and Methods: 251 patients diagnosed with stage III colon carcinoma treated with surgery followed by 5-FU based adjuvant therapy were selected. The variable number of tandem repeats (VNTR) and the single nucleotide polymorphism (SNP) in the 5′-untranslated region of the TS gene were genotyped.Results: There was a positive association between tumor T stage and the VNTR genotypes (p=0.05). In both univariate and multivariate survival analysis no effects of the studied polymorphisms on survival were found. However, there was an association between both polymorphisms and age. Among patients younger than 60 years, the patients homozygous for 2R seemed to have a better overall survival, whereas among the patients older than 67 this longer survival was seen by the carriers of other genotypes.Conclusion: We conclude that the TS VNTR and SNP do not predict response to 5-FU therapy in patients with stage III colon carcinoma. However, age appears to modify the effects of TS polymorphisms on survival.
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Knop, Stefan, Juergen Loeffler, Michael Steffens, Markus Guenther, Agnieszka Korfel, Michael Weller, Holger Hebart, Hermann Einsele et Ulrich Herrlinger. « Polymorphisms in Genes of Folate Metabolism and Response to High-Dose Methotrexate in Patients with Primary Central Nervous System Lymphoma. » Blood 106, no 11 (16 novembre 2005) : 4439. http://dx.doi.org/10.1182/blood.v106.11.4439.4439.
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Abstract The antifolate methotrexate (MTX) was shown to be the single most-effective agent in first-line treatment of patients with primary central nervous system lymphoma (PCNSL) when given intravenously in high doses. MTX inhibits 5,10-methylentetrahydrofolate reductase (MTHFR) as well as thymidylate synthase (TS) in target cells what eventually results in decreased DNA synthesis. Intracellular uptake of both folate and MTX is mediated by the reduced folate carrier (RFC). Genetic polymorphisms for all three proteins were described: a C to T base transition at nucleotide 667 (C677T) and an A to C transition at 1298 (A1298C) of MTHFR; a 28-base pair (bp) tandemly repeated sequence polymorphic in the numbers of the repeat (2R/2R; 3R/3R; and 2R/3R) in the 5′-UTR of TS; a 6bp insertion-(+6bp)/deletion(−6bp)-polymorphism in the 3′-UTR of TS; and a polymorphism at nucleotide 80 (G80A) of RFC. We hypothesized that these polymorphisms may be directly linked to response, survival and toxicity in patients with PCNSL who are treated with single high-dose MTX. We prospectively collected blood from 152 subjects who were enrolled into a German multicenter PCNSL trial. They were scheduled to receive HD-MTX 4 g/m2 every 2 weeks. Genomic DNA was extracted from mononuclear cells using QIAGEN DNA Blood Mini Kit®. Genotyping of the two MTHFR (C677T; A1298C) and the RFC (G80A) single nucleotide polymorphisms (SNPs) was performed by melting point analysis with Master Hybridization Probes® using the Light Cycler® technology. Genotyping of the TS 28bp tandem/triplet repeats in the 5′-UTR was performed by conventional PCR followed by high resolution agarose gel electrophoresis. The TS +6bp/−6bp polymorphism in the 3′-UTR was analyzed with PCR, followed by restriction enzyme digest with draI and agarose gel electrophoresis. The fragment sizes were 70 bp and 88 bp for the 6 bp insertion allele and 152 bp for the 6 bp deletion allele. Allele frequencies for heterozygosity and for homozygous mutations of the two MTHFR and the RFC SNPs as well as of the two TS polymorphisms were as expected for a Caucasian population. For the currently 120 evaluable patients logistic regression analysis, Armitage Trend test and Kaplan-Meier survival curves were performed to analyze the role of the polymorphisms as potential predictors for MTX response. Up to now, we only found a trend for an association between response to treatment and survival for the 2 MTHFR mutations. We will analyze haematological and non-haematological toxicities which will be presented at the meeting with updated results for survival and response in the patients who will have completed treatment until then.
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Ugrasena, IDG, Sutaryo Sutaryo, Edy Supriadi, Laura Vroling, Jacqueline Cloos, Jan Hendrik Hooijberg et AJP Veerman. « High frequency of the 3R/3R polymorphism in the thymidylate synthase enhancer region in Indonesian childhood acute lymphoblastic leukemia ». Paediatrica Indonesiana 46, no 3 (18 octobre 2016) : 103. http://dx.doi.org/10.14238/pi46.3.2006.103-12.
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Background Deoxyuridylate monophosphate (dTMP) is neces-sary for DNA synthesis and thymidylate synthase (TS) is an im-portant target of cancer chemotherapy. Ethnic variations of thepolymorphic tandem repeat sequence in the enhancer region ofthe TS promoter has previously been described to influence theoutcome of acute lymphoblastic leukemia (ALL). A triple repeat isassociated with a higher TS gene expression than a double re-peat, resulting in poorer outcome of ALL patients treated with anti-folate methotrexate (MTX).Objective In this study, we determined the incidences of TS andmethylenetetrahydrofolate reductase (MTHFR) polymorphism andethnic variations between Indonesian and Caucasian ALL cellsamples obtained at diagnosis. Furthermore, we determined theinvolvement of TS polymorphisms in MTX sensitivity using athymidilate synthase inhibition assay (TSIA).Methods ALL cell samples were obtained at diagnosis from 101Indonesian and 157 Caucasian children treated with MTX prospec-tively. Genotyping for TS and MTHFR was analyzed by Genescanand Lightcycler. TS polymorphism was determined by PCR assayand MTHFR polymorphism and was analyzed by melting curveanalyses on lightcycler.Results Homozygous TS triple repeats were more than twice ascommon in Indonesian samples (76.3%) than in Caucasian samples(33.1%). Heterozygotes of the MTHFR mutations were seen in 15%of the screened Indonesian samples.Conclusion There are significant ethnic variations in TS generegulatory elements of leukemic cells. A difference was found be-tween the MTX sensitivity and a double or triple repeat in the Cau-casian ALL group. The samples with a triple repeat show a shift intheir distribution towards hypersensitivity to MTX. Further investi-gation on Indonesian samples may give insight in the role of poly-morphisms in MTX sensitivity
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Ichikawa, W., T. Takahashi et Y. Sasaki. « Pharmacogenetic profiling and clinical outcome of patients (pts) with advanced gastric cancer (AGC) treated with S-1 monotherapy ». Journal of Clinical Oncology 25, no 18_suppl (20 juin 2007) : 4600. http://dx.doi.org/10.1200/jco.2007.25.18_suppl.4600.
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4600 Background: Intra-tumor gene expressions of thymidylate synthase (TS) and orotate phosphoribosyltranseferase (OPRT) have been indicated to be positive predictive markers for the clinical outcome of pts treated by S-1 monotherapy for AGC (Int J Cancer 119:1245,2006). The aim of this study is to investigate whether polymorphisms with putative influence on S-1 activity are associated with clinical outcomes of pts with AGC. Patients and Methods: The study population consisted of consecutive 55 pts with AGC from 01/1999 to 03/2002 in our institute. All patients homogenously received the S-1 monotherapy (80mg/sqm/day, 4 wks with 2-wks drug holiday) as a first line treatment. The overall response rate was 40% and the median overall survival (OS) was 8.0 months (range, 2.1 to 23.0 months). Genomic DNA obtained before starting chemotherapy was used for genotyping 8 polymorphisms in 5 genes (DPD, TS, OPRT, MTHFR, CYP2A6). Results: No alleles of DPYD*2 were found in this Japanese cohort. There were no association among the clinical outcome, such as tumor response and OS, and genotypes including tandem repeat (VNTR) in TS 5’UTR, G/C polymorphism with in the 3R VNTR, OPRT G638C, MTHFR C677T, CYP2A6*4, and CYP2A6*9. Even if TS 5’UTR and G/C polymorphism were combined, TS 5’UTR 3G genotype (2R/3G, 3C/3G, 3G/3G) was not associated with the clinical outcome. Only 6-bp insertion/deletion (ins/del) in the TS 3’UTR was closely related to both tumor response and OS. The response rates were 23% and 55% in pts with del/del genotype and pts with ins/ins or ins/del, respectively, with a statistical significance (P=0.015). The median OS was 9.5 months in pts with the ins allele versus 6.2 months in pts with del homozygote (P=0.0345). Conclusion: This exploratory study shows that polymorphism in TS 3’UTR may influence clinical outcomes of AGC pts treated by S-1. No significant financial relationships to disclose.
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Aguiar, Samuel, Eloisa Olivieri, Dirce Maria Carraro, Celso Lopes Mello, Marcelo Fanelli et Ademar Lopes. « Association of the polymorphisms of the tandem repeat sequence in the thymidylate synthase gene with tumor stage in colon cancer. » Journal of Clinical Oncology 31, no 15_suppl (20 mai 2013) : e14688-e14688. http://dx.doi.org/10.1200/jco.2013.31.15_suppl.e14688.
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e14688 Background: Thymidylate synthase (TS) plays an important role in colorectal carcinogenesis and response to 5FU-based chemotherapy. TS expression can be modified due to polymorphisms in the 5'-untranslated region (5’-UTR) of the gene. The aim of this study is to investigate the association between TS polymorphisms with clinicopathological characteristics of colon carcinomas. Methods: we retrospectively studied 89 individuals with high risk stage II (obstruction, T4 stage, presence of lymphovascular invasion or preoperative CEA > 5.0) and stage III patients submitted to curative intent surgery. DNA was extracted from paraffin embedded tumor tissues and sequenced. The polymorphism studied was the variation of the number of the repeated 28-bp sequences (3 or 2 repeats) of the TS gene 5’-UTR. Results: The frequency of the polymorphisms was: 2R2R in 26 cases (29.2%), 2R3R in 36 cases (40.4%), and 3R3R in 27 cases (30.3%). We did not find associations between the frequencies of these polymorphisms and age, gender, presence of lymphovascular invasion, or level of preoperative CEA. We find a significantly higher proportion of T4 tumors between the 3R3R genotype compared with the 2R2R and 2R3R genotypes (OR=2.69; 95% CI: 1.05 – 6.94; p=0.04). By the other hand, a significantly lower proportion of positive lymph nodes were found among patients with tumors presenting the 3R3R genotype, by comparing with the 2R2R and 2R3R subgroup (OR: 0.28; 95%CI: 0.10 – 0.72; p=0.01). Five-year disease free survival and overall survival were, respectively, 81% and 85% among patients with tumors presenting the 3R3R genotype, and 62% and 67% among patients with tumors presenting 2R2R or 2R3R genotypes. These differences were not statistically significant. Conclusions: in this sample, the TS polymorphic tumor genotype 3R3R was associated with lower risk of lymph node metastases in colon carcinomas.
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Mulder, K. E., C. A. Butts, A. Scarfe, H. Au, S. Koski, A. Fields, J. Hanson, M. Kuzma, K. Graham et M. B. Sawyer. « A prospective pharmacogenetic study of thymidylate synthase (TS) polymorphisms in high risk stage II or stage III colon cancer patients treated with 5-fluorouracil (5-FU) and leucovorin (LV) ». Journal of Clinical Oncology 24, no 18_suppl (20 juin 2006) : 13018. http://dx.doi.org/10.1200/jco.2006.24.18_suppl.13018.
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13018 Background: Retrospective studies suggest TS polymorphisms predict toxicity from TS inhibitors as well as therapeutic response. The TS promoter has a variable number of tandem repeats (VNTR) polymorphism containing putative E-box binding sites that bind upstream stimulatory factor (USF) -1 and -2. One E-box binding site exists in TSER*2 and 2 binding sites exist in TSER*3. A single nucleotide polymorphism (SNP) at position 12 (G→C) in TSER*3’s 2nd repeat abolishes binding of USF-1/2. Combined effects of VNTR and SNP means individuals may have 2, 3 or 4 enhancer regions. We hypothesized that decreased enhancer numbers predicts for patients at risk for grade ≥3 mucositis, diarrhea, neutropenia, and overall toxicity and performed a prospective pharmacogenetic study of TS polymorphisms in adjuvant colon cancer patients treated with 5-FU/LV. Methods: High risk Stage II or Stage III colon cancer patients treated with 5FU/LV (425 mg/m2/ 20 mg/m2) daily for 5 days every 4 weeks had blood drawn for genotyping prior to starting therapy. Patients were assessed for toxicity using NCI CTC 2.0 in cycle 1. Three year disease-free survival will also be assessed. Results: 103 patients were enrolled and genotyped with 95 evaluable for toxicity. Patient characteristics: median age 61yrs (36–79): M 52%/F 48%; Stage III 77%, Stage II 23%. Frequency of genotypes containing 2 enhancers (TSER*2/ TSER*2, TSER*2 / TSER*3C, TSER*3C/ TSER*3C), 3 enhancers (TSER*2/ TSER*3G, TSER*3C/ TSER*3G) and 4 enhancers (TSER*3G/ TSER*3G) was 0.64, 0.31, and 0.05 respectively. No significant difference was seen in overall toxicity, mucositis, diarrhea and neutropenia based on TS polymorphism genotypes. Frequency of recurrence in 2 enhancer patients was 13% versus 26% in 3/4 enhancer patients but this did not reach statistical significance (p = 0.16). Conclusions: This prospective study does not confirm previously published retrospective studies suggesting that TS VNTR and SNP predict toxicity from TS inhibitors in patients treated with 5-fluorouracil for colon cancer. There is a trend for prediction of recurrence which requires further follow-up. No significant financial relationships to disclose.
Thèses sur le sujet "Ts polymorphism"
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LOTTO, VALENTINA. « Nutrient-gene interactions within one-carbon metabolism and effects on epigenetic regulation through dna methylation in peripheral blood mononuclear cells ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2010. http://hdl.handle.net/10281/18016.
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Epigenetics is a field of molecular biology that copes with the study of gene function regulation without variations in DNA structure or nucleotide sequences.
Among the main epigenetic phenomema in eukaryotic cells there are DNA methylation and post-traslational mechanisms among which the major are histone methylation and acetylation.
Epigenetic changes are potentially reversible phenomena that are controlled also by nutritional factors as the methyl-donors involved in the folate cycle.
Plasma levels of B vitamins, among which “in primis” plasma folate concentrations, are implicated in epigenetic modulation so that it can be hypothesized that they may affect the modulation of gene expression through epigenetic mechanisms.
Epigenetic modifications represent one of the earliest events in the genesis of some complex pathologies, therefore the study of the interaction between epigenetics and nutritional status is of great interest either to define the physiopathological mechanisms of development of some illnesses, and for possible personalized strategies of prevention.
The present work has been articulated, at first, on the analysis of gene-nutritional interaction mechanisms within the folate cycle through the study of polymorphisms of enzymes involved in the metabolism of methyl-group donors; the aim was to study their possible role on the modulation of genomic DNA methylation in relationship to different plasma levels of idrosoluble B vitamins. In this regard, the most important functional polymorfisms known on the genes of one-carbon metabolism and their relationship with methylation status of polymorphonuclear cells DNA have been analyzed from a cohort of around 800 subjects within a clinical study, underlining the role of the key folate-related enzymes in the modulation of DNA methylation.
Besides the function of genomic DNA methylation, the methylation status at specific sites has been also approached with the specific intent of considering a possible interrelationship between the role of promoter methylation and the co-presence of functional polymorphisms in the same genic site for a gene for which a precise functional effect is well-known. To address this issue the promoter region of coagulation factor VII gene was evaluated for both genetic and epigenetic modifications as a possible model of genetic-epigenetic interaction in the modulation of gene product regulation. The results showed the key importance of genetic-epigenetic interactions, so far unknowm, in modulating gene-expression at promoter gene sites.
The role of other vitamins involved in one-carbon metabolism in major chronic diseases, and specifically the emerging role of B6 vitamin, have been also studied.
Furthermore, a clinical study is now in progress to evaluate the function of gene-specific methylation in liver tissue where most of the folate cycle functions take place. The aim of this project is the evaluation of both genome-wide and gene-specific methylation status in the liver in comparison to that observed in peripheral blood mononuclear cells DNA to define whether methylation status of peripheral blood DNA may be regarded as a good systemic biomarker for this epigenetic feature of DNA in relation to B vitamins nutritional status in cancer disease. Results from this study may help to define possible functional markers of gene-nutrients interactions with effects on epigenetic modulation for future preventive or therapeutic strategies. With that purpose, a novel high-throughput array-based technique for the detection of gene-specific methylation at promoter sites has been optimized in our laboratory.
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Hinkle, David T. « CORRELATING IRINOTECAN AND CAPECITABINE TREATMENT FOR COLORECTAL CANCER TO GENE EXPRESSION, POLYMORPHISMS, AND CLINICAL OUTCOMES ». Thesis, 2011. http://hdl.handle.net/1805/2510.
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Indiana University-Purdue University Indianapolis (IUPUI)Colorectal cancer is the third most common type of cancer and the third most common cause of cancer-related mortality. There are three types of treatment available to patients, either individually or in combination. Treatments are radiation, chemotherapy, and surgery. In a Phase II clinical trial at IUSM, a multimodality approach was chosen. The patients with locally advanced rectal cancer received preoperative treatment with capecitabine and irinotecan (CPT-11) combination followed by chemoradiation with capecitabine and finally surgery to improve response and decrease local recurrence. Irinotecan and Capecitabine are both prodrugs activated in vivo to SN-38 and 5-FU, respectively. Identification of the molecular markers for 5-FU and Irinotecan efficacy and toxicity is important for the development of more efficient and less toxic treatment strategies for patients with colorectal cancer. The goal of this study was to determine the expression levels of the genes involved in activation and metabolism of capecitabine and irinotecan in pre and post treatment specimens from these patients. The genes quantitated by real-time PCR were carboxylesterase 1 and 2 (CES1 and CES2), thymidylate synthase (TS), β-glucoronidase (β-GUS), thymidine phosphorylase (TP), dihydropyrimidine dehydrogenase (DPD) and topoisomerase I (Topo I). The UGT1A1*28 polymorphism in UDP glucuronosyltransferase 1 is associated with SN-38 toxicity. Therefore, the UGT1A1*28 polymorphism status in patients was determined by PCR-sequencing. Correlative analysis of gene expression and UGT1A1*28 mutation with clinical outcome in this Phase II study was completed.
Chapitres de livres sur le sujet "Ts polymorphism"
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Clayton, Peter, Pierre Chatelain, Elena Bashnina, Jia-Woei Hou, Cheri Deal, Sylvie Cabrol, Benoit Destenaves et al. « Using Single Nucleotide Polymorphisms (SNPs) To Predict Year 1 and Year 2 Growth Response to Growth Hormone (GH) Therapy in Children with GH Deficiency (GHD) and Turner Syndrome (TS) ». Dans CLINICAL/TRANSLATIONAL - Growth Disorders, P1–736—P1–736. The Endocrine Society, 2011. http://dx.doi.org/10.1210/endo-meetings.2011.part2.p19.p1-736.
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Chatelain, Pierre, Peter Clayton, Valentina Peterkova, Alicia Belgorosky, Mohamad Maghnie, Franco Antoniazzi, Benoit Destenaves et al. « Comparison of Single Nucleotide Polymorphisms (SNPs) Associated with Growth Response at Years 1 and 2 on Growth Hormone (GH) Therapy in Children with GH Deficiency (GHD) and Turner Syndrome (TS) ». Dans CLINICAL/TRANSLATIONAL - Growth Disorders, P1–735—P1–735. The Endocrine Society, 2011. http://dx.doi.org/10.1210/endo-meetings.2011.part2.p19.p1-735.
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