IGlutathione S-transferase (GSTM1 and GSTT1) Polymorphisms in Cervical Cancer in Northeastern Thailand

To evaluate the relationships between genetic polymorphisms of the GSTs (GSTM1 and GSTT1) and cervicalcancer, the null genotype of each gene was studied in squamous cell cervical cancer (SCCA) patients (n=90) andcontrols (n=94) in Northeast Thailand. The prevalence of the GSTM1-null genotype in the controls and SCCApatients was 59.6% and 60.0%, respectively, whereas those of the GSTT1-null genotype in the control andSCCA patients was 40.4% and 46.7%, respectively. Neither of the GST-null genotypes increased the risk forSCCA (p>0.05); however, the combination of the GSTM-1 and GSTT1-null genotypes showed a non-significanttrend to an increased risk for developing cervical cancer with an adjusted OR of 2.7 (95%CI=0.8-9.0, p=0.10).Genetic polymorphisms of GSTM1 and GSTT1 were not significant risk factors for cervical cancer in eithertobacco-smokers or non-smokers. A different contribution of the GST genotype to cancer risk may be attributedto a different, as yet undefined, property of the enzymes.     

Genetic Polymorphisms of Xenobiotic Metabolizing Genes (GSTM1, GSTT1, GSTP1), Gene-Gene Interaction with Association to Lung Cancer Risk in North India; A Case Control Study

Aim: In this case control study involving, 220 human subjects; polymorphisms in xenobiotic metabolizing genes (GST-M1, -T1 and -P1) and their association to lung cancer risk is being analysed among smokers and non-smokers. GSTM1 or GSTT1 gene polymorphism and amino acid changes in GSTP1 have been correlated and may be associated to lung cancer risk. Other factor includes exposure to environmental pollutants and life style choices. We have explored gene-gene and gene-environment interaction in the aetiology of lung cancer risk among north Indian population. Patients and Methods: For the study we have collected 120 lung cancer patient blood samples from Kamala Nehru Memorial Cancer Hospital, Allahabad, Uttar Pradesh and 100 matched controls. DNA was isolated and GST-M1 and - T1 genotyping were assessed by multiplex PCR whereas the GSTP1 polymorphism was analysed using restriction fragment length polymorphism. The risk of lung carcinogenesis was assessed using logistic regression analysis calculating the odd ratio (OR) with 95% confidence interval (CI). Results: The risk of lung carcinogenesis was three fold higher for null GSTT1 (OR=3.045, 95%CI=1.750-5.301, p-value <0.001) genotype; whereas other two types; GSTM1 (OR= 1.342, 95% CI=0.788-2.284, p-value=0.270) and GSTP1 (OR=0.806, 95% CI=0.526-1.236, p-value=0.323) showed no association to lung cancer susceptibility respectively. Smokers diagnosed with lung cancer had more null genotypes for GSTT1 (OR=4.773, 95%CI=1.939-11.751, p<0.001). The ‘at risk’ genotype combination GSTM1 (null) /GSTT1 (null) (OR=1.76, 95%CI; 0.920-3.370, p-value=0.03) showed increased susceptibility to lung cancer risk. The genotype combination of GSTT1 (null)/GSTP1 (Ile/Ile) (p=0.009) was associated with increased lung cancer risk. Conclusion: The results of this study suggest that; GSTT1 null genotype were more susceptible for lung cancer risk and smoking increases the susceptibility for lung cancer several folds among the North Indian population. Gene-gene interaction for null genotypes of GSTM1 and GSTT1 were correlated with higher risk of having lung cancer.     

Lack of Assocation of Glutathione S-transferase T1 Gene Null and Susceptibility to Lung Cancer in China: a Meta-analysis

Background: Variation in metabolic genes is regarded as an important factor in processes leading to cancer.However, the effect of GSTT1 null genotype is divergent in the form of lung cancer. Methods: Studies wereconducted at different research databases from 1990 to 2013 and the total odds ratio (OR) and 95% confidenceinterval (CI) were calculated for lung cancer. Review Manager 5.2 and STATE 12 are employed. Results: TotalOR value is calculated from 17 articles with 2,118 cases and 2,915 controls. We discovered no significant increasein lung cancer risk among subjects carrying GSTT1 null genotype [OR = 1.15; 95% CI 0.97-1.36] in this metaanalysis.Conclusion: The GSTT1 deletion polymorphism does not have a significant effect on the susceptibilityto lung cancer overall in China.     

Meta-analysis of GSTM1 and GSTT1 Polymorphisms and Riskof Nasopharyngeal Cancer

Background: Studies of associations between genetic polymorphism of glutathione S-transferase M1 (GSTM1)and glutathione S-transferase T1 (GSTT1) with risk of nasopharyngeal cancer (NPC) have generated conflictingresults. Thus, a meta-analysis was performed to clarify the effects of GSTM1 and GSTT1 polymorphisms on therisk of developing NPC. Materials and Methods: A literature search in two electronic databases namely PubMedand EMBASE up to December 2012 was conducted and eligible papers were finally selected based on the inclusionand exclusion criteria. The pooled odds ratio (OR) and presence of heterogeneity and publication bias in thosestudies were evaluated. Results: A total of 9 studies concerning nasopharyngeal cancer were evaluated. Analysesof all relevant studies showed increased NPC risk to be significantly associated with the null genotypes of GSTMI(OR=1.43, 95%CI 1.24-1.66) and GSTT1 (OR=1.28, 95%CI=1.09-1.51). In addition, evidence of publication biaswas detected among the studies on GSTM1 polymorphism. Conclusions: This meta-analysis demonstrated theGSTM1 and GSTT1 null genotypes are associated with an increased risk of NPC.     

Glutathione-S-transferase (GSTM1, GSTT1) Null Phenotypes and Risk of Lung Cancer in a Korean Population

Purpose: The aim of this study was to evaluate any association of GSTM1 and GSTT1 null genotypes withthe risk of lung cancer in a South Korean population. Methods: We conducted a large-scale, population-basedcase-control study including 3,933 lung cancer cases and 1,699 controls. Genotypes of GSTM1 and GSTT1 weredetermined using real-time polymerase chain reaction. Results: In logistic regression analysis adjusted for age andsmoking, we did not find any association between GSTM1 or GSTT1 and LC risk in women. However, in men,the GSTM1 and GSTTI null genotypes were borderline associated with risk (OR=1.18, 95% CI=0.99-1.41 forGSTM1, OR=1.18, 95% CI=0.99-1.41 for GSTT1), and combined GSTM1 and GSTT1 null genotypes conferredan increased risk for LC in men (OR=1.39, 95% CI=1.08–1.78). The OR for the GSTT1 null genotype was greaterin subjects aged 55 years old or younger (OR=1.45, 95% CI=1.09-1.92 for men; OR=1.36, 95% CI=0.97–1.90for women), than in those over age 55 (OR=1.03, 95% CI=0.83-1.27 for men; OR=0.86, 95% CI=0.66–1.12 forwomen) in both genders (p for interaction <0.05). Conclusions: In the Korean population, the GSTM1 andGSTT1 null genotypes are risk factors for LC in men; the GSTT1 null genotype has a more prominent effecton LC risk in younger people (age 55 years and under) than in older individuals.     

GSTM1 and GSTT1 Genetic Polymorphisms and Breast Cancer Risk in Selected Filipino Cases

Background: The association of genetic polymorphisms with cancer development has been shown to be race- andtumor site-specific. Thus, this study aimed to determine whether polymorphisms in the GSTM1 and GSTT1 genesare associated with breast cancer among selected Filipinos. Methods: A total of 136 histologically confirmed breastcancer cases were age- and sex-matched with 136 clinically healthy controls. Genomic DNA extracted from bloodsamples of participants were screened for GSTM1 and GSTT1 genetic polymorphisms by multiplex PCR. Results:The frequency of null genotypes among the cases (GSTM1: n=78; 57.4%; GSTT1: n=61; 44.9%) was not significantlydifferent (p>0.05) from the controls (GSTM1: n=93; 68.4%; GSTT1: n=59; 43.4%). It was also demonstrated that riskfor breast cancer was increased in passive smokers carrying the GSTM1 null (OR=2.56; 95% CI=1.38-4.75) or GSTT1positive (OR=2.00; 95% CI=1.05-3.83) genotypes. Moreover, risk was decreased in alcohol users carrying the GSTT1null (OR=0.39; 95% CI=0.16-0.97) genotype. Conclusion: This study suggests that variants of GSTM1 and GSTT1may not be risk factors for breast cancer development among Filipinos. However, the risk may be increased when thesegenotypes were combined with lifestyle or environmental factors.     

Null Glutathione S-transferase T1 and M1 Genotypes and Oral Cancer Susceptibility in China and India - a Meta-analysis

Objective: Genetic variation is considered to strongly impact on detoxification of carcinogens and thereforeis related to cancer risk. However, findings for the null genotypes of GSTT1 and GSTM1 have not always beenconsistent. Therefore the present meta-analysis was conducted. Methods: We accessed the reported study atdifferent research areas and used various databases, including PubMed and Wanfang Med Onlion from 1990to May 1st 2013. We calculated the odds ratio (OR), 95% confidence interval (CI) and P value for oral cancerby using Review Manager 5.1 and STATE 12. Results: We found that there was no increased oral cancer riskamong subjects carrying GSTM1 and GSTT1 null genotype (OR=1.35, 95%CI=0.68-2.68, P=0.39) and (OR=1.41,95%CI=0.72-2.77, P=0.31) in the Chinese population. In contrast, in studies in India a significant correlationbetween GSTM1 null genotype and oral cancer was observed (OR=1.59, 95%CI=1.20-2.11, P=0.001), but not inGSTT1 (OR=1.21, 95% CI = 0.84-1.74, P=0.31). Conclusion: We discovered that GSTM1 deletion polymorphismhad a significant effect on the susceptibility of oral cancer in the Indian population.     

谷胱甘肽硫转移酶M1基因多态性与食管癌Meta分析

[目的]综合评价谷胱甘肽硫转移酶M1(GSTM1)基因多态性与食管癌易患性的相关性。[方法]应用Meta分析方法对国内外9篇有关GSTM1因多态性与食管癌的病例对照研究进行定量综合分析，共积累病例845例，对照1267例。统计处理采用Meta分析的固定效应模型和随机效应模型。[结果]在排除一个超溢值后，8个病例对照研究的合并OR为1．622，95％可信度为1．323～1．988。[结论]GSTM1基因多态性与食管癌的易患性有关，即GSTM1空白基因型可增加患食管癌的危险性。     

Polymorphism in GSTM1, GSTT1, and GSTP1 and Susceptibility to Lung Cancer in a Japanese Population

Polymorphisms in glutathione S-transferases (GSTs) may predispose to lung cancer through deficient detoxification ‍of carcinogenic or toxic constituents in cigarette smoke, although previous results have been conflicting. Three GST ‍polymorphisms (GSTM1, GSTT1 and GSTP1) were determined among 86 male patients with lung carcinomas and ‍88 healthy male subjects. We found no significant increase in the risk of lung cancer for any genotypes for the nulled ‍GSTM1 [odds ratio (OR)=2.0; 95% confidence interval (95% CI)= 0.8-5.3], the nulled GSTT1 (OR=2.0; 95% CI=0.8- ‍5.1) or the mutated (the presence of a Val-105 allele) GSTP1 (OR=0.96; 95% CI=0.4-5.5). The GST polymorphisms ‍alone may thus not be associated with susceptibility to lung carcinogenesis in male Japanese. However, individuals ‍with a concurrent lack of GSTM1 and GSTT1 had a significantly increased risk (OR=2.7; 95% CI=1.0-7.4) when ‍compared with those having at least one of these genes. No other combinations were associated with lung cancer ‍risk. These results suggest that there may be carcinogenic intermediates in cigarette smoke that are substrates for ‍both GSTM1 and GSTT1 enzymes and that lung cancer risk is increased for individuals who are doubly deleted at ‍GSTM1 and GSTT1 gene loci. Additional large studies are needed to confirm this observation.     

Associations of CYP1A1, GSTM1 and GSTT1 Polymorphisms with Lung Cancer Susceptibility in a Northern Indian Population

Background: Susceptibility to lung cancer has been shown to be modulated by inheritance of polymorphicgenes encoding cytochrome P450 1A1 (CYP1A1) and glutathione S transferases (GSTM1 and GSTT1), which areinvolved in the bioactivation and detoxification of environmental toxins. This might be a factor in the variation inlung cancer incidence with ethnicity. Materials and Methods: We conducted a case-control study of 218 northernIndian lung cancer patients along with 238 healthy controls, to assess any association between CYP1A1, GSTM1and GSTT1 polymorphisms, either separately or in combination, with the likelihood of development of Lungcancer in our population. Results: We observed a significant difference in the GSTT1 null deletion frequency in thispopulation when compared with other populations (OR=1.87, 95%CI: 1.25-2.80–0.73, P=0.002). However, GSTM1null genotype was found associated with lung cancer in the non-smoking subgroup. (P=0.170). Conclusions: Ourstudy showed the GSTT1 null polymorphism to be associated with smoking-induced lung cancer and the GSTM1null polymorphism to have a link with non-smoking related lung cancer.     

Glutathione S-transferase M1 and T1 status and the risk of laryngeal cancer: a meta-analysis

Background: Polymorphic variations in GSTM1 and GSTT1 have been implicated as risk factors for various cancers. A number of studies conducted to assess their association with susceptibility to laryngeal carcinomas have yielded inconsistent and inconclusive results. In the present study, the possible association of laryngeal cancer risk with GSTM1 and GSTT1 null genotypes was explored by a meta analysis. Method: A meta-analysis was carried out on case-control studies collected from the literature. The pooled odds ratio (OR) and presence of publication bias in those studies were evaluated. Results: A total of 20 studies concerning laryngeal cancer were identified. The results showed that the pooled OR was 1.22 (95% CI 1.03-1.43) for the GSTM1 polymorphism while for GSTT1 polymorphism, the pooled OR was 1.23 (95% CI 0.96-1.58). No evidence of publication bias was detected among the included studies. Conclusion: The results suggest that the GSTM1 deficiency significantly increases susceptibility to laryngeal cancer whereas GSTT1 null genotype might not be a risk factor.     

GSTM1 Polymorphisms and Lung Cancer Risk in the Chinese Population: a Meta-Analysis Based on 47 Studies

Although a number of studies have been conducted on the association between GSTM1 polymorphismsand lung cancer in China, this association remains elusive and controversial. To clarify the effects of GSTM1polymorphisms on the risk of lung cancer, a meta-analysis was performed in the Chinese population. Relatedstudies were identified from PubMed, Springer Link, Ovid, Chinese Wanfang Data Knowledge Service Platform,Chinese National Knowledge Infrastructure (CNKI), and Chinese Biology Medicine (CBM) up to 5th April 2014.A total of 45 articles (47 studies) including 6,623 cases and 7,865 controls were involved in this meta-analysis.Overall, a significant association (OR = 1.45, 95%CI: 1.32-1.60) was found between the null GSTM1 and lungcancer risk when all studies in Chinese population pooled into the meta-analysis. In subgroup analyses stratifiedby quality score, geographic area and source of controls, the same results were observed under all the models.This meta-analysis showed that the null GSTM1 may be a potential biomarker for lung cancer risk in Chinese,but further studies with gene-gene and gene-environment interactions are required for definite conclusions.     

CYP1A1, GSTM1, GSTT1 and TP53 Polymorphisms and Risk of Gallbladder Cancer in Bolivians

The Plurinational State of Bolivia (Bolivia) has a high incidence rate of gallbladder cancer (GBC). However, the genetic and environmental risk factors for GBC development are not well understood. We aimed to assess whether or not cytochrome P450 (CYP1A1), glutathione S-transferase mu 1 (GSTM1), theta 1 (GSTT1) and tumor suppressor protein p53 (TP53) genetic polymorphisms modulate GBC susceptibility in Bolivians. This case-control study covered 32 patients with GBC and 86 healthy subjects. GBC was diagnosed on the basis of histological analysis of tissues at the Instituto de Gastroenterologia Boliviano Japones (IGBJ); the healthy subjects were members of the staff at the IGBJ. Distributions of the CYP1A1 rs1048943 and TP53 rs1042522 polymorphisms were assayed using PCR-restriction fragment length polymorphism assay. GSTM1 and GSTT1 deletion polymorphisms were detected by a multiplex PCR assay. The frequency of the GSTM1 null genotype was significantly higher in GBC patients than in the healthy subjects (odds ratio [OR], 2.35; 95% confidence interval [CI], 1.03-5.37; age-adjusted OR, 3.53; 95% CI, 1.29-9.66; age- and sex-adjusted OR, 3.40; 95% CI, 1.24-9.34). No significant differences were observed in the frequencies of CYP1A1, GSTT1, or TP53 polymorphisms between the two groups. The GSTM1 null genotype was associated with increased GBC risk in Bolivians. Additional studies with larger control and case populations are warranted to confirm the association between the GSTM1 deletion polymorphism and GBC risk suggested in the present study.     

Lack of Associations between Genetic Polymorphisms in GSTM1, GSTT1 and GSTP1 and Pancreatic Cancer Risk: A Multi-Institutional Case-Control Study in Japan

Background: We aimed to evaluate the role of genetic polymorphisms in tobacco carcinogen-metabolizinggenes and their interactions with smoking in a hospital-based case-control study of Japanese subjects. Materialsand Methods: We examine the associations of pancreatic cancer risk with genetic polymorphisms in GSTM1,GSTT1 and GSTP1, phase II enzymes that catalyze the conjugation of toxic and carcinogenic electrophilicmolecules. The study population consisted of 360 patients and 400 control subjects, who were recruited fromseveral medical facilities in Japan. Unconditional logistic regression methods were used to estimate odds ratios(ORs) and 95% confidence intervals (CIs) for the associations between genotypes and pancreatic cancer risk.Results: Among the control subjects, the prevalence of the GSTM1-null genotype and the GSTT1-null genotypewas approximately 56% and 48%, respectively. Cases and controls were comparable in terms of GSTM1 andGSTT1 genotype distributions. Neither of the deleted polymorphisms in GSTM1 and GSTT1 was associated withthe risk of pancreatic cancer, with an age- and sex-adjusted OR of 0.99 (95%CI: 0.74-1.32) for the GSTM1-nullgenotype, and 0.98 (95%CI: 0.73-1.31) for the GSTT1-null genotype. The OR was 0.97 (95%CI: 0.64-1.47) forindividuals with the GSTM1 and GSTT1-null genotypes compared with those with the GSTM1 and GSTT1-present genotypes. No synergistic effects of smoking or GST genotypes were observed. Conclusions: Our resultsindicate no overall association between the GSTM1 and GSTT1 deletion polymorphisms and pancreatic cancerrisk in the Japanese subjects in our study.     

Meta-analysis of the association between GSTM1 and GSTT1 gene polymorphisms and cervical cancer

Aim: We conducted a meta-analysis to analyze the influence of GSTM1 and GSTT1 gene polymorphisms on cervical cancer risk, and explore gene-environment interactions. Methods: Identification of relevant studies was carried out through a search of Medline and the EMbase up to Oct. 2011. All case-control studies that investigated the association between GSTM1 and GSTT1 gene polymorphisms and risk of cervical cancer were included. The pooled odds ratio (OR) was used for analyses of results and the corresponding 95% confidence intervals (CI) were estimated. Results: A total of 21 case-control studies were included in the meta-analysis of GSTM1 (2,378 cases and 2,639 controls) and GSTT1 (1,229 cases and 1,223 controls) genotypes. The overall results showed that the GSTM1 null was related to an increased risk of cervical cancer (OR=1.50, 95% CI=1.21-1.85). Subgroup analysis were performed based on smoking and ethnicity. Our results showed that smokers with null GSTM1 genotype had a moderate increased risk of cervical cancer (OR=1.85, 95% CI=1.07-3.20). For the ethnicity stratification, moderate significantly increased risk of null GSTM1 genotype was found in Chinese (OR=2.12, 95% CI=1.43-3.15) and Indian populations (OR=2.07, 95% CI=1.49-2.88), but no increased risk was noted in others. Conclusion: This meta-analysis provided strong evidence that the GSTM1 genotype is associated with the development of cervical cancer, especially in smokers, and Chinese and Indian populations. However, no association was found for GSTT1 null genotype carriers.     

Polymorphisms of CYP1A1, GSTM1, GSTT1, and prostate cancer risk in Turkish population

Prostate cancer is the most common cancer among men in many countries. Although the etiology of prostate cancer largely is unknown, both genetic and environmental factors may be involved. Advanced age, androgen metabolism, and heredity-race have been reported to be possible risk factors. On the other hand, several studies indicate that genetic polymorphisms in biotransformation enzymes play a role in prostate cancer development. In this study, association of the prostate cancer risk with genotype frequencies of the Phase I (CYP1A1) and Phase II (GSTM1 and GSTT1) biotransformation enzymes was investigated in 321 Turkish individuals (152 prostate cancer patients and 169 age-matched male controls). The presence or absences of the GSTM1 and GSTT1 genes were determined by a PCR-based method. Genotypes of CYP1A1 were determined by MspI-RFLP. The prevalence of GSTM1 null genotype in the cases was 64 percent, compared to 31 percent in the control group, indicating a strong association (OR = 4.08, 95%CI = 2.50-6.69). No association was observed between either GSTT1 null genotype or CYP1A1 polymorphism and prostate cancer incidence. No statistically significant association was observed between smoking status of the patients and any of the polymorphisms studied. In conclusion, results of this study indicate that only the GSTM1 null genotype may play an important role as a risk factor for prostate cancer development in Turkish population.     

Genetic Polymorphisms of GSTM1 and GSTT1 Genes in Delhi and Comparison with other Indian and Global Populations

The glutathione S-transferases (GSTs) are involved in the metabolism of many xenobiotics, including an arrayof environmental carcinogens, pollutants, and drugs. Genetic polymorphisms in these genes may lead to interindividualvariation in susceptibility to various diseases. In the present study, GSTM1 and GSTT1 polymorphismswere analysed using a multiplex polymerase chain reaction in 500 normal individuals from Delhi. The frequencyof individuals with GSTM1 and GSTT1 null genotypes were 168 (33.6%) and 62 (12.4%) respectively, and54(10.8%) were having homozygous null genotype for both the genes GSTM1 and GSTT1simultaneously. Thestudied population was compared with reported frequencies from other neighbouring state populations, aswell as with those from other ethnic groups; Europeans, Blacks, and Asians. The prevalence of homozygousnull GSTM1 genotype is significantly higher in Caucasians and Asians as compared to Indian population. Thefrequency of GSTT1 homozygous null genotypes is also significantly higher in blacks and Asians. We believethat due to large number of individuals in this study, our results are reliable estimates of the frequencies of theGSTM1, GSTT1 in Delhi. It would provide a basic database for future clinical and genetic studies pertaining tosusceptibility and inconsistency in the response and/or toxicity to drugs known to be the substrates for GSTs.     

Triplex Polymerase Chain Reaction with Confronting Two-Pair Primers (PCR-CTPP) for NQO1 C609T,GSTM1 and GSTT1 Polymorphisms: the Most Convenient Genotyping Method

The polymerase chain reaction with confronting two-pair primers (PCR-CTPP) is a time-saving and inexpensive ‍genotyping method, which is applicable for most single nucleotide polymorphisms (SNPs). To date, we have established ‍PCR-CTPP conditions for tens of SNPs, including duplex genotyping. This paper introduces triplex PCR-CTPP to ‍simultaneously genotype three functional polymorphisms of carcinogen-detoxifying enzymes, NQO1 C609T, GSTM1 ‍null, and GSTT1 null, all of which are reported to have a significant association with smoking-related cancers. We ‍applied this method for 241 non-cancer patients to demonstrate the performance. Among the subjects, the genotype ‍frequency of NQO1 C609T was 35.7% for CC, 44.4% for CT and 19.9% for TT. The null type frequencies of GSTM1 ‍and GSTT1 were 53.4% and 44.0%, respectively. Their distributions were similar to those reported for Japanese by ‍other studies. This is the first paper reporting the success of triplex PCR-CTPP. The polymorphisms applied are ‍useful examples, which could be adopted not only for research purposes, but also for risk assessment of individuals ‍exposed to carcinogenic substances, such as smokers. This convenient genotyping approach has advantages for ‍application in cancer prevention, especially in the Asian Pacific region.     

GSTM1 and GSTT1 Polymorphisms and Susceptibility to Prostate Cancer: A Case-Control Study of the Algerian Population

Objective: Prostate cancer (PCa) is a major public health problem worldwide, with high morbidity and mortality levels. Advanced age, androgen stimulation, and ethnicity have been reported to be possible risk factors. It has been suggested that particular genetic polymorphisms in glutathione S-transferases (GST), xenobiotic-metabolising enzymes, could predispose to prostate cancer through heritable deficiency in detoxification of environmental carcinogens. Conflicts in the published results and the absence of similar in depth studies in Algeria prompted us to perform the present case-control study of GSTM1 and GSTT1 polymorphisms and their possible association with PCa in an Algerian population. Methods: We determined GSTM1 and GSTT1 genotypes for 49 histologically verified prostate cancer patients and in 41 age-matched healthy controls by multiplex polymerase chain reaction (PCR) using peripheral blood DNA samples. Result: While an association between the GSTM1 null genotype and PCa risk (OR= 3.69, 95% CI= 1.30-10.44; P = 0.01) was evident, the GSTT1 null genotype (OR= 0.92, 95% IC= 0.32-2.62; P = 0.49) appeared without influence. Furthermore, no statistically significant differences between the double null genotype and PCa is detected, also no statistically significant differences between smoking status and PCa is detected. Conclusion: The GSTM1 null genotype may increase individual susceptibility to prostate cancer. On the other hand, the null-activity genotype of GSTT1 did not appear to contribute to the risk of prostate cancer in our population.     

Frequency and Association Of GSTM1 and GSTT1 Gene Polymorphisms with Survival in Breast Cancer Patients

Objective: Glutathione S-transferase M1 and T1 (GSTM1 and GSTT1) are the key detoxification enzymes of xenobiotics, including chemotherapeutic drugs. The deletion polymorphisms of GSTM1 and GSTT1 genes are associated with reduced enzyme activity that influenced clinical outcomes of chemotherapeutic agents in breast cancer. However, there is limited information among Thai patients. This research aims to explore the frequency and role of GSTM1 and GSTT1 polymorphisms on survival among Thai patients with breast cancer. Methods: The retrospective cohort study was performed. Demographic data and clinicopathology characteristics were collected from hospital base registry data and medical records. A multiplex qualitative real-time PCR method was used to detect the presence or absence of the GSTM1 and GSTT1 gene in the genomic DNA samples of the participants. Results: The frequencies of the GSTM1 and GSTT1 null genotypes in 198 breast cancer patients were 65.70% and 33.30%, respectively. The overall survival at 1, 3 and 5 years were 95.00%, 83.00%, 71.00% respectively. The log rank test and Cox proportional hazards revealed a significant different in the 5-years overall survival according to lymph node metastasis and tumor stage (P = 0.014 and P < 0.001). No associations between overall survival and GSTM1 or GSTT1 genotype were found in single or combined genotypes analyses (P = 0.76 and P= 0.15). Conclusion: The results of our study provided the epidemiological information for prognostic of survival in breast cancer patients treated with chemotherapy.