Gene Summary

Gene:GSTT1; glutathione S-transferase theta 1
Summary:The protein encoded by this gene, glutathione S-transferase (GST) theta 1 (GSTT1), is a member of a superfamily of proteins that catalyze the conjugation of reduced glutathione to a variety of electrophilic and hydrophobic compounds. Human GSTs can be divided into five main classes: alpha, mu, pi, theta, and zeta. The theta class includes GSTT1, GSTT2, and GSTT2B. GSTT1 and GSTT2/GSTT2B share 55% amino acid sequence identity and may play a role in human carcinogenesis. The GSTT1 gene is haplotype-specific and is absent from 38% of the population. Alternative splicing of this gene results in multiple transcript variants. [provided by RefSeq, Sep 2015]
Databases:OMIM, HGNC, GeneCard, Gene
Protein:glutathione S-transferase theta-1
Source:NCBIAccessed: 13 March, 2017


What does this gene/protein do?
Show (5)
Pathways:What pathways are this gene/protein implicaed in?
Show (2)

Cancer Overview

Research Indicators

Publications Per Year (1992-2017)
Graph generated 13 March 2017 using data from PubMed using criteria.

Literature Analysis

Mouse over the terms for more detail; many indicate links which you can click for dedicated pages about the topic.

Tag cloud generated 13 March, 2017 using data from PubMed, MeSH and CancerIndex

Latest Publications: GSTT1 (cancer-related)

Negovan A, Iancu M, Moldovan V, et al.
The Interaction between GSTT1, GSTM1, and GSTP1 Ile105Val Gene Polymorphisms and Environmental Risk Factors in Premalignant Gastric Lesions Risk.
Biomed Res Int. 2017; 2017:7365080 [PubMed] Free Access to Full Article Related Publications
The study investigated the possible influence of GSTM1, GSTT1, and GSTP1 gene polymorphisms as predisposing factors for premalignant gastric lesions as well as their interaction with H. pylori infection, gastrotoxic drugs, smoking, and alcohol consumption. In this study, 270 patients with a complet set of gastric biopsies and successfully genotyped were finally included. The GSTM1 gene polymorphism had significant contribution in mild/severe endoscopic lesions (p = 0.01) as well as in premalignant lesions (p = 0.01). The GSTM1 null genotype increased the risk for mucosal defects in H. pylori-negative patients (OR = 2.27, 95% CI: 1.20-4.37) and the risk for premalignant lesions in patients with no alcohol consumption (OR = 2.13, 95% CI: 1.19-3.83). The GSTT1 deleted polymorphism did not significantly increase the risk for premalignant lesions in the absence of gastrotoxic drugs (OR = 1.82, 95% CI: 0.72-4.74). The combined GSTT1T1 and GSTM1 null polymorphisms were borderline correlated with an increased risk for premalignant lesions (OR = 1.72, 95% CI: 1.00-2.97). The wild-type GSTP1 Ile/Ile genotype versus the variant genotypes Ile/Val + Val/Val was significantly associated with a decreased risk of gastric atrophy/intestinal metaplasia (OR = 0.60, 95% CI: 0.37-0.98). In conclusion, the GSTM1 and GSTT1 null genotypes increased the risk for premalignant and endoscopic gastric lesions, modulated by H. pylori, alcohol, or gastrotoxic drug consumption, while the presence of the GSTP1Val allele seemed to reduce the risk for premalignant lesions.

Jia W, Sun JY, Jia KY, Liu XC
Role of GSTM1, GSTT1, and GSTP1 IIe105Val gene polymorphisms in the response to chemotherapy and overall survival of advanced non-small cell lung cancer.
Genet Mol Res. 2016; 15(3) [PubMed] Related Publications
We evaluated the association between GSTM1, GSTT1, and GSTP1 IIe105Val gene polymorphisms and treatment outcomes of advanced non-small cell lung carcinoma. Between January 2010 and December 2012, a total of 244 patients with non-small cell lung carcinoma were recruited from Yiwu Central Hospital. The GSTM1, GSTT1, and GSTP1 IIe105Val gene polymorphisms were analyzed by polymerase chain reaction-restriction fragment length polymorphism and the results were statistically analyzed. Conditional regression analysis, showed that individuals carrying the null GSTM1 were associated with an increased risk of response to chemotherapy when compared to the present GSTM1 (odds ratio = 1.88, 95% confidence interval (CI) = 1.01-3.47). Moreover, the GG genotype of GSTP1 IIe105Val was associated with a better response to chemotherapy compared to the AA genotype (odds ratio = 2.77, 95%CI = 1.14-6.64). The null GSTM1 genotype was associated with a lower risk of death from all causes when compared with the present GSTM1 genotype (hazard ratio = 2.16, 95%CI = 1.10-4.38). Moreover, the GG genotype of GSTP1 IIe105Val was correlated with a reduced risk of death from all causes compared with the AA genotype (hazard ratio = 2.94, 95%CI = 1.11-8.68). In conclusion, we found that the null GSTM1 and the GG genotype of GSTP1 IIe105Val were correlated with a good response to chemotherapy and improved overall survival of advanced non-small cell lung carcinoma patients.

Malik SS, Kazmi Z, Fatima I, et al.
Genetic Polymorphism of GSTM1 and GSTT1 and Risk of Prostatic Carcinoma - a Meta-analysis of 7,281 Prostate Cancer Cases and 9,082 Healthy Controls.
Asian Pac J Cancer Prev. 2016; 17(5):2629-35 [PubMed] Related Publications
Genetic polymorphisms constitute one of the reasons behind the racial variation in prostate cancer occurrence. Published studies regarding genetic associations of glutathione S-transferase mu 1 (GSTM1) and glutathione S-transferase theta 1 (GSTT1) null deletion polymorphisms with prostatic carcinoma have generated inconsistent results among different populations. To date, even a single meta-analysis is not available representing the association of these genes with prostate cancer in different ethnic groups. Therefore, the aim of the current study was to provide a clear picture of GSTM1 and GSTT1 null deletion and risk of prostate cancer among different ethnic groups (i.e. Asians, Europeans, Americans, Africans and Eurasians). A systematic search was performed with the help of various search engines to find out the all the recent studies (2004 to 2015) evaluating the role of GSTM1 and GSTT1 deletion in prostate cancer development. Odds ratios (ORs) with 95% confidence interval (CI) of a total of 34 studies with 7,281 cases and 9,082 controls was analyzed using STATA and MedCalc software. Overall, GSTM1 deletion (OR 3.67; CI 1.39-9.85; P= 0.001) was strongly associated with prostatic cancer. In the sub group analysis GSTM1 null deletion was also significantly associated with prostate cancer among Asians (OR 4.84; CI 1.08-21.5; P= 0.03), Eurasians (OR 17.69; CI 9.87-31.70; <0.001) and Americans (OR 0.11; CI 0.01-1.06; P= 0.05). No association was observed among Europeans (P=0.42) and Africans (P= 0.40). As a whole GSTT1 null deletion (OR 0.85; CI 0.28-2.58; P= 0.77) did not show anyt significant association with prostate cancer risk among different populations. When the data were stratified into different groups, however, Africans demonstrated a significant association of GSTT1 null deletion (OR 1.95; CI 1.57-2.39; <0.001) with prostate cancer, whereas no association was found among Asians (P= 0.90), Americans (P= 0.50), Europeans (P= 0.89) and Eurasians (P= 1.0). In conclusion, both GSTM1 and GSTT1 may contribute to prostate cancer development but GSTM1 may prove to be a stronger candidate risk factor.

Peddireddy V, Badabagni SP, Gundimeda SD, et al.
Association of CYP1A1, GSTM1 and GSTT1 gene polymorphisms with risk of non-small cell lung cancer in Andhra Pradesh region of South India.
Eur J Med Res. 2016; 21:17 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Lung cancer is one of the most preventable causes of death globally both in developed and developing countries. Although it is well established that smokers develop lung cancer, there are some smokers who are free from the disease risk. The predisposition to lung cancer is attributed to genetic polymorphisms in xenobiotic metabolizing genes. Reports on assessment of xenobiotic metabolizing genes like Cytochrome P 450 1A1 (CYP1A1), Glutathione -S -transferase M1 (GSTM1) and T1 (GSTT1) polymorphisms from India are meagre, and reports from Andhra Pradesh are lacking.
METHODS AND RESULTS: Assessment of polymorphisms in CYP1A1, GSTM1 and GSTT1 in NSCLC patients and healthy individuals specific to population of Andhra Pradesh, a South Indian state was attempted by multiplex PCR and RFLP, and this is the first study which tried to correlate oxidative stress with the polymorphisms in xenobiotic metabolizing genes. Results showed that CYP1A1 m1 'CC' genotype was significantly associated with lung cancer susceptibility with a 2.3-fold risk, CYP1A1 m2 'AG' gene polymorphisms with 8.8-fold risk and GSTT1 (-/-) genotype demonstrated a twofold risk of disease susceptibility.
CONCLUSIONS: A combined role of genetic polymorphisms and smoking status can be attributed for the cause of lung cancer. Further, the association between oxidative stress and genetic polymorphisms showed a correlation between GSTT1 and super oxide dismutase activity; CYP1A1 m1, m2 and GSTT1 with glutathione peroxidase activity; CYP1A1 m1 and GSTM1 with melondialdehyde levels; and CYP1A1 m1 and GSTT1 with 8-oxo-7,8-dihydro-2'-deoxyguanosine. A higher risk of lung cancer seems to be associated with combined gene polymorphisms of phase I and phase II enzymes than that ascribed to single gene polymorphism.

Zeng Y, Bai J, Deng LC, et al.
Association of the Glutathione S-transferase T1 Null Genotype with Risk of Gastric Cancer: a Meta-analysis in Asian Populations.
Asian Pac J Cancer Prev. 2016; 17(3):1141-8 [PubMed] Related Publications
BACKGROUND: A large number of studies have been published to investigate the association between the null genotype of glutathione S-transferase T1 (GSTT1) with gastric cancer. However, the results were inconsistent and conflicting. The aim of this study was to estimate the relationship between this polymorphism in the GSTT1 gene and gastric cancer risk in Asian populations by meta-analysis.
MATERIALS AND METHODS: A literature search was performed in PubMed, Embase, Chinese Biomedical database (CBM), Weipu database, Wanfang database, and China National Knowledge Infrastructure database (CNKI). Statistical analysis was conducted by using Review Manager 5.3.
RESULTS: Thirty-nine studies with a total of 7,737 gastric cancer cases and 10,823 controls were included in this meta-analysis. The meta-analysis of total studies showed that the null genotype in GSTT1 was associated with increased risk of gastric cancer in Asians (OR=1.19, 95% CI=1.08-1.31, p=0.0002). Subgroup analysis showed a significant relationship between GSTT1 null genotype and gastric cancer in East-Asians, as well as in subgroup analysis of hospital-based design. On subgroup analysis by smoking status, alcohol status, Helicobacter pylori infection status, and histology type, no significant association of this polymorphism with susceptibility to gastric cancer was found.
CONCLUSIONS: In conclusion, the results showed that the null genotype of GSTT1 is significantly associated with an increased risk in gastric cancer in Asian populations.

Ghatak S, Yadav RP, Lalrohlui F, et al.
Xenobiotic Pathway Gene Polymorphisms Associated with Gastric Cancer in High Risk Mizo-Mongoloid Population, Northeast India.
Helicobacter. 2016; 21(6):523-535 [PubMed] Related Publications
BACKGROUND: The aim of this study was to evaluate the risk of gastric cancer associated with individual or combined glutathione S-transferases (GSTs) polymorphism and their interaction with environmental factors.
MATERIALS AND METHODS: Genotyping by PCR was carried out for 80 cases and controls each for GSTM1, GSTT1, and GSTP1 polymorphism and mapped for gene-environment association studies. The samples were subjected to pathogen detection and GSTP1 expression for analyzing their association with different genotypes. Logistic regression analyses were conducted to compute the influence of both genetic and environmental factors for gastric cancer. MDR analysis was performed to assess the risk of gastric cancer by studying the gene-gene and gene-environment effect on the basis of GST genotyping and GSTP1 gene expression.
RESULTS: Infection with Helicobacter pylori and CagA+ strains was more frequent in patients with GSTM1/T1 null genotype. Intake of high fermented fat and smoked meat was found to be significantly associated with gastric cancer. The G/G, A/G (rs1695), and T/T (rs1138272) were found to be significantly associated with low expression of GSTP1 gene in cancer tissue.
CONCLUSION: Presence of H. pylori with CagA genotype showed significant individual effect with GSTT1 polymorphism as well as strong synergistic effect in gastric cancer risk. Majority of the gastric cancer samples showed significant negative expression in G/G, A/G (rs1695), and T/T (rs1138272) genotypes. This study shows that GST gene polymorphism was significantly relevant for determining the individual susceptibility to gastric cancer.

Nasr AS, Sami RM, Ibrahim NY, Darwish DO
Glutathione S transferase (GSTP 1, GSTM 1, and GSTT 1) gene polymorphisms in Egyptian patients with acute myeloid leukemia.
Indian J Cancer. 2015 Oct-Dec; 52(4):490-5 [PubMed] Related Publications
BACKGROUND: The super family of glutathione S-transferases (GSTs) is composed of multiple isoenzymes with significant evidence of functional polymorphic variation. GSTs detoxify potentially mutagenic and toxic DNA-reactive electrophiles, including metabolites of several chemotherapeutic agents, some of which are suspected human carcinogens. Polymorphisms within the phase II metabolizer enzymes GST T1, GST M1, and GST P1 affect the body's ability to detoxify a range of potential leukemogens encountered in the environment.
AIM OF WORK: To address how differences in the human GST isoenzyme expression patterns influence cancer susceptibility, prognosis, and treatment.
PATIENTS AND METHODS: A total of 50 patients with acute myeloid leukemia (AML), as well as 50 age and sex matched apparently healthy volunteers were genotyped for GSTP 1, GSTM 1, and GSTT 1 gene polymorphisms using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and conventional polymerase chain reaction (PCR), respectively.
RESULTS: For GSTP1 313 A → G (GSTP1 Ile105Val) polymorphism, It was found that the wild genotype (AA) was significantly higher among control subjects (P value = 0.0277), while the frequency of heteromutant genotype (AG) and mutant G allele (AG + GG) was significantly higher among patients (P value = 0.0402, P value = 0.0277, respectively). For GSTM1 and GSTT1gene, we found statistically significantly higher frequency among patients regarding homozygous gene deletion (P value = 0.0005).
CONCLUSION: We demonstrated that GSTM1 null or GSTT1 null genotypes may be considered independent risk factors for AML with no impact on prognosis and GSTP1 * 105 genotype is a prognostic factor, adding independent information to the routine laboratory parameters and cytogenetic and molecular alterations of the tumor cells.

Bănescu C, Iancu M, Trifa AP, et al.
From Six Gene Polymorphisms of the Antioxidant System, Only GPX Pro198Leu and GSTP1 Ile105Val Modulate the Risk of Acute Myeloid Leukemia.
Oxid Med Cell Longev. 2016; 2016:2536705 [PubMed] Free Access to Full Article Related Publications
Oxidative stress might contribute to the occurrence of cancers, including the hematological ones. Various genetic polymorphisms were shown to increase the quantity of reactive oxygen species, a phenomenon that is able to induce mutations and thus promote cancers. The purpose of the study was to evaluate the association between CAT C262T, GPX1 Pro198Leu, MnSOD Ala16Val, GSTM1, GSTT1, and GSTP1 Ile105Val gene polymorphisms and acute myeloid leukemia risk, in a case-control study comprising 102 patients and 303 controls. No association was observed between AML and variant genotypes of CAT, MnSOD, GSTM1, and GSTT1 polymorphisms. Our data revealed a statistically significant difference regarding the frequencies of GPX1 Pro198Leu and GSTP1 Ile105Val variant genotypes between AML patients and controls (p < 0.001). Our results showed no association in the distribution of any of the CAT C262T, GPX1 Pro198Leu, GSTM1, GSTT1, and GSTP1 polymorphisms regarding age, gender, FAB subtype, cytogenetic risk groups, FLT3 and DNMT3 gene mutations, and overall survival. Our data suggests that the presence of variant allele and genotype of GPX1 Pro198Leu and GSTP1 Ile105Val gene polymorphisms may modulate the risk of developing AML.

Mostafavi SS, Ebrahimi A, Sadat SM, et al.
Impact of null genotypes of GSTT1 and GSTM1 with uterine leiomyoma risk in Iranian population.
J Obstet Gynaecol Res. 2016; 42(4):434-9 [PubMed] Related Publications
AIM: Few studies have investigated the role of the GSTM1 and GSTT1 genes in uterine leiomyoma. Therefore, in the current study the distribution of these genotypes in Iranian women and susceptibility to uterine leiomyoma was investigated.
METHODS: Blood samples of 50 patients with uterine leiomyoma and 50 healthy individual controls were collected in this cross-sectional study. Genomic DNA was extracted, and subsequently GSTM1 and GSTT1 null genotypes were detected by the Gap-polymerase chain reaction method.
RESULTS: A total of 42% of patients appeared to lack GSTM1 enzyme activity due to the presence of an extended deletion (GSTM1 0/0 genotype), compared with 18% in a control group (odds ratio [OR], 3.56; 95% confidence interval [CI], 1.35-9.37; P < 0.010). In addition, the prevalence of the GSTT1 null genotype in patients was higher than that in the control group (42% to 14%, P < 0.009). Also, it was shown that individuals with both null genotypes (-/-) had a 19.23-fold higher risk of developing the disease in comparison to people who showed both present genotypes (+/+). (P = 0.007; 95%CI, 2.20-167.41). Besides, it was observed that at least one null genotype increases the risk of myoma to 2.6 compared to the both present genotype (P-value < 0.03, 95%CI, 1.05-6.82).
CONCLUSION: To our knowledge, this is first significant correlation between risk of uterine leiomyoma and null GSTM1 and GSTT1 genotypes among Iranian patients. Our data support the involvement of GSTM1 and GSTT1 in uterine leiomyoma liability, and especially its role as a genetic factor in the occurrence of this disease.

Rodrigues DA, Costa IR, Martins JV, et al.
Polymorphisms of GSTM1, GSTT1, and p53 in Goiânia, Goiás.
Genet Mol Res. 2015; 14(4):17358-65 [PubMed] Related Publications
Genetic polymorphisms are defined as changes within the DNA sequences of genes that have frequencies in the population higher than 1%. The glutathione S-transferases play an important role in the cellular detoxification systems involved in oxidative stress that can lead to accumulation of reactive oxygen species. Epidemiological studies have suggested that individuals with homozygous deletion of glutathione S-transferase mu 1 (GSTM1) and glutathione S-transferase theta 1 (GSTT1) are at higher risk of developing several types of neoplasias. The p53 protein is highly expressed in tumors and transformed cells, and the p53 is a classical tumor suppressor gene involved in regulating cell growth and development. In this study, we investigated the prevalence of polymorphisms in the p53, GSTM1, and GSTT1 genes in a population from Goiânia. We evaluated the polymorphisms of these genes in peripheral blood samples. The null or present polymorphism of GSTM1 and GSTT1 genes and Arg/Pro of the p53 gene were analyzed. Our results revealed a higher frequency of the GSTM1-null polymorphism (72.4%) than the GSTM1-present genotype (27.6%). For GSTT1, we observed higher frequency for the null genotype (65.5%) compared to the present genotype (34.5%). Analysis of p53 gene polymorphisms showed a higher frequency for the genotype Arg/Pro (66%) and a lower frequency for the Arg/Arg (23%) and Pro/Pro (11%) genotypes. It is essential to understand polymorphism frequencies in different populations and to evaluate the role of genetic polymorphisms and their effects on health.

Ghosh S, Ghosh S, Bankura B, et al.
Association of DNA repair and xenobiotic pathway gene polymorphisms with genetic susceptibility to gastric cancer patients in West Bengal, India.
Tumour Biol. 2016; 37(7):9139-49 [PubMed] Related Publications
Gastric cancer is one of the most common malignancies in India. DNA repair gene or xenobiotic pathway gene polymorphisms have recently been shown to affect individual susceptibility to gastric cancer. Here, the possible interaction between common polymorphisms in X-ray repair cross complementing group I (XRCC1) gene and glutathione S-transferase (GST) genes (GSTM1, GSTT1 and GSTP1), smoking and alcohol consumption and overall survival in gastric cancer patients were evaluated. In this population-based case control study, 70 gastric cancer patients and 82 healthy controls were enrolled. The epidemiological data were collected by a standard questionnaire, and blood samples were collected from each individual. XRCC1 Arg194Trp, Arg280His and Arg399Gln polymorphisms were determined by polymerase chain reaction and direct DNA sequencing. GSTM1 and GSTT1 null polymorphisms and GSTP1 Ile105Val polymorphism were identified by multiplex polymerase chain reaction and restriction fragment length polymorphism (RFLP), respectively. The risk of gastric cancer was significantly elevated in individuals with XRCC1 Arg/Gln +Gln/Gln (p = 0.031; odds ratio = 2.32; 95 % confidence interval (CI) 1.07-5.06) and GSTP1 Val/Val genotype (p = 0.009; odds ratio = 8.64; 95 % CI 1.84-40.55). An elevated risk for GC was observed in smokers and alcohol consumers carrying GSTP1 Ile/Val +Val/Val genotype (p = 0.041; odds ratio = 3.71; 95 % CI 0.98-14.12; p = 0.002; odds ratio = 12.31; 95 % CI 1.71-88.59). These findings suggest that XRCC1 rs25487 and GSTP1 rs1695 can be considered as a risk factor associated with gastric cancer and might be used as a molecular marker for evaluating the susceptibility of the disease.

Wu G, Jiang B, Liu X, et al.
Association of GSTs gene polymorphisms with treatment outcome of advanced non-small cell lung cancer patients with cisplatin-based chemotherapy.
Int J Clin Exp Pathol. 2015; 8(10):13346-52 [PubMed] Free Access to Full Article Related Publications
We evaluated the association of GSTM1 null/present, GSTT1 null/present, and GSTP1 IIe105Val polymorphisms with the clinical response to chemotherapy and treatment outcome of NSCLC. Between October 2009 and October 2012, a total of 282 patients with advanced NSCLC were enrolled into our study, and they were followed up until October 2014. The genotypes of GSTM1, GSTT1, and GSTP1 IIe105Val were performed by polymerase chain reaction (PCR) coupled with restriction fragment length polymorphism (RFLP). By logistic regression analysis, our study found that the Val/Val genotype of GSTP1 IIe105Val was associated with more CR+PR response to chemotherapy when compared with the IIe/IIe genotype, and the OR (95% CI) was 2.18 (1.16-4.12). By multivariate Cox proportional hazards regression analysis, we found the Val/Val genotype of GSTP1 was correlated with lower risk of death in advanced NSCLC (HR, 0.48; 95% CI, 0.25-0.93). However, no association was found between GSTT1 and GSTM1 polymorphisms and response to chemotherapy and overall survival of advanced NSCLC. Moreover, the IIe/Val + Val/Val genotypes of GSTP1 were associated with lower risk of death in never smokers, and the adjusted HR (95% CI) was 0.34 (0.12-0.93). In conclusion, we found that the GSTP1 polymorphism was correlated with better response to chemotherapy and lower risk of death in advanced NSCLC patients.

Huang W, Shi H, Hou Q, et al.
GSTM1 and GSTT1 polymorphisms contribute to renal cell carcinoma risk: evidence from an updated meta-analysis.
Sci Rep. 2015; 5:17971 [PubMed] Free Access to Full Article Related Publications
Emerging evidences suggest that GSTM1 and GSTT1 are involved in the detoxification of carcinogens, and polymorphisms in this gene that result in a loss of enzyme activity may increase the risk of renal cell carcinoma (RCC). Thus, to evaluate the association of GSTM1 and GSTT1 polymorphisms and RCC, we performed an updated meta-analysis of 10 case-control studies by RevMan 5.2, and the publication bias was tested using STATA 11.0. The meta-analysis showed that the single locus GSTM1 and GSTT1 polymorphisms were not significantly associated with a risk of RCC in a recessive model. However, that wild-type genotype versus the dual null genotype of GSTM1-GSTT1 showed a positive association with RCC risk (OR = 0.70; 95% CI = 0.51-0.98; P = 0.04). In another analysis of subjects exposed to pesticides, we found that the GSTM1 wild-type genotype was associated with increased RCC risk in Europeans (OR = 2.72; 95% CI = 1.54-4.82; P = 0.0006). We also identified an association between the GSTT1 wild-type and lower RCC TNM staging (I + II versus III + IV: OR = 1.88; 95% CI = 1.09-3.26; P = 0.02). This meta-analysis suggests that there may be a relationship between the GSTM1 and GSTT1 wild-type genotype and RCC.

Stavrinou P, Mavrogiorgou MC, Polyzoidis K, et al.
Expression Profile of Genes Related to Drug Metabolism in Human Brain Tumors.
PLoS One. 2015; 10(11):e0143285 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Endogenous and exogenous compounds as well as carcinogens are metabolized and detoxified by phase I and II enzymes, the activity of which could be crucial to the inactivation and hence susceptibility to carcinogenic factors. The expression of these enzymes in human brain tumor tissue has not been investigated sufficiently. We studied the association between tumor pathology and the expression profile of seven phase I and II drug metabolizing genes (CYP1A1, CYP1B1, ALDH3A1, AOX1, GSTP1, GSTT1 and GSTM3) and some of their proteins.
METHODS: Using qRT-PCR and western blotting analysis the gene and protein expression in a cohort of 77 tumors were investigated. The major tumor subtypes were meningioma, astrocytoma and brain metastases, -the later all adenocarcinomas from a lung primary.
RESULTS: Meningeal tumors showed higher expression levels for AOX1, CYP1B1, GSTM3 and GSTP1. For AOX1, GSTM and GSTP1 this could be verified on a protein level as well. A negative correlation between the WHO degree of malignancy and the strength of expression was identified on both transcriptional and translational level for AOX1, GSTM3 and GSTP1, although the results could have been biased by the prevalence of meningiomas and glioblastomas in the inevitably bipolar distribution of the WHO grades. A correlation between the gene expression and the protein product was observed for AOX1, GSTP1 and GSTM3 in astrocytomas.
CONCLUSIONS: The various CNS tumors show different patterns of drug metabolizing gene expression. Our results suggest that the most important factor governing the expression of these enzymes is the histological subtype and to a far lesser extent the degree of malignancy itself.

Abbas M, Kushwaha VS, Srivastava K, Banerjee M
Glutathione S-Transferase Gene Polymorphisms and Treatment Outcome in Cervical Cancer Patients under Concomitant Chemoradiation.
PLoS One. 2015; 10(11):e0142501 [PubMed] Free Access to Full Article Related Publications
PURPOSE: Cisplatin based concomitant chemoradiation (CRT) is the standard treatment for locally advanced cervical cancer (CC). Glutathione S-transferase (GST), a phase II antioxidant enzyme is induced by oxidative stress generated by drugs and reactive oxidants. The present study was undertaken to evaluate the association of GSTM1, T1 and P1 polymorphisms with the outcome of CRT treatment in CC patients.
METHODS: A total of 227 cervical cancer patients with stages IIB-IIIB treated with the same chemoradiotherapy regimen were enrolled and genotyped for GSTM1, T1 and P1 gene polymorphisms by multiplex polymerase chain reaction (mPCR) and PCR-restriction fragment length polymorphism (PCR-RFLP). Overall survival was evaluated using Kaplan-Meier survival function and Cox proportional hazards model. All data were analyzed using SPSS (version 21.0).
RESULTS: Stratified analysis showed that GSTM1 null (M1-) genotype was associated with a significantly better survival among patients with stage IIB cervical cancer (log-rank P = 0.004) than cases with stage IIIA/IIIB. Death and recurrence were significantly higher in patients with GSTM1 present genotype (M1+) (P = 0.037 and P = 0.003 respectively) and those with M1- showed reduced hazard of death with an adjusted hazard ratio 'HR' of 0.47 (95% CI, 0.269-0.802, P = 0.006). Women with M1- genotype as well as in combination with GSTT1 null (T1-), GSTP1 (AG+GG) and GSTT1 null/GSTP1 (AG+GG) showed better survival and also reduced risk of death (HR = 0.31, P = 0.016; HR = 0.45, P = 0.013; HR = 0.31, P = 0.02 respectively).
CONCLUSIONS: To the best of our knowledge, this is the first study to correlate the association of GSTM1, T1 and P1 gene polymorphisms with treatment outcome of CRT treated CC patients. Our results suggested that individuals with GSTM1 null genotype and in combination with GSTT1 null and GSTP1 (AG+GG) had a survival advantage. Such genetic studies may provide prognostic information in CRT treated CC patients.

Sharma N, Singh A, Singh N, et al.
Genetic polymorphisms in GSTM1, GSTT1 and GSTP1 genes and risk of lung cancer in a North Indian population.
Cancer Epidemiol. 2015; 39(6):947-55 [PubMed] Related Publications
BACKGROUND: A number of studies done so far in different populations have shown that polymorphisms within the GST genes play an important role in determining individual susceptibility to lung cancer; however, data obtained so far have been contradictory within the same or different populations. Few studies have focused on the combinatorial effect of the GST genes on susceptibility to lung cancer and also for different histological subtypes. Our aim is to investigate the roles of GSTM1, GSTT1, and GSTP1 polymorphisms as genetic modifiers of risk for lung cancer and histological subtypes using a larger sample size in a North Indian population.
METHODS: In total 540 subjects (270 lung cancer cases and 270 controls) were evaluated for the GST polymorphism. Genotyping for the GSTM1, GSTT1 and GSTP1 gene was done by using a multiplex PCR and PCR-RFLP method.
RESULTS: GSTM1 null genotype was found to be associated with lung cancer (OR=1.65, 95%CI: 116-2.3, P=0.005) and this risk was higher in cases of adenocarcinoma (ADCC). GSTT1 and GSTP1 did not show any significant association with lung cancer; however, when stratified for histological subtypes a significant association was observed for ADCC and small-cell lung cancer (SCLC) for both GSTT1 null and variant GSTP1 genotypes. The combined 'at risk' genotypes of null GSTM1 and GSTT1 genes were found to be associated with lung cancer risk, and this risk was higher in cases of ADCC (OR=4.09, 95%CI: 110-10.2, P=0.002). There is a twofold increased risk for lung cancer with the null GSTM1 and wild-type GSTP1 genotypes (P=0.0004); similarly, a fourfold increased risk was observed with the null GSTT1 and wild-type GSTP1 genotypes (P=0.0001).
CONCLUSIONS: The deficient GST genotypes seem thus to be important risk modifiers for lung cancer and related histological subtypes, especially in combination.

Li XM, Yu XW, Yuan Y, et al.
Glutathione S-transferase P1, gene-gene interaction, and lung cancer susceptibility in the Chinese population: An updated meta-analysis and review.
J Cancer Res Ther. 2015 Jul-Sep; 11(3):565-70 [PubMed] Related Publications
AIM OF STUDY: To assess the impact of glutathione S-transferase P1 (GSTP1) Ile105Val polymorphism on the risk of lung cancer in the Chinese population, an updated meta-analysis and review was performed.
MATERIALS AND METHODS: Relevant studies were identified from PubMed, Springer Link, Ovid, Chinese Wanfang Data Knowledge Service Platform, Chinese National Knowledge Infrastructure, and Chinese Biology Medicine published through January 22, 2015. The odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to estimate the strength of the associations.
RESULTS: A total of 13 case-control studies, including 2026 lung cancer cases and 2451 controls, were included in this meta-analysis. Overall, significantly increased lung cancer risk was associated with the variant genotypes of GSTP1 polymorphism in the Chinese population (GG vs. AA: OR=1.36, 95% CI=1.01-1.84). In subgroup analyses stratified by geographic area and source of controls, the significant results were found in population-based studies (GG vs. AA: OR=1.62, 95% CI: 1.13-2.31; GG vs. AG: OR=1.49, 95% CI: 1.03-2.16; GG vs. AA+AG: OR=1.55, 95% CI: 1.12-2.26). A gene-gene interaction analysis showed that there was an interaction for individuals with combination of GSTM1 (or GSTT1) null genotype and GSTP1 (AG+GG) mutant genotype for lung cancer risk in Chinese.
CONCLUSION: This meta-analysis suggests that GSTP1 Ile105Val polymorphism may increase the risk of lung cancer in the Chinese population.

Sharma A, Gupta S, Sodhani P, et al.
Glutathione S-transferase M1 and T1 Polymorphisms, Cigarette Smoking and HPV Infection in Precancerous and Cancerous Lesions of the Uterine Cervix.
Asian Pac J Cancer Prev. 2015; 16(15):6429-38 [PubMed] Related Publications
Glutathione S-transferases (GSTs) play an important role in detoxification of carcinogenic electrophiles. The null genotypes in GSTM1 and GSTT1 have been implicated in carcinogenesis. Present study was planned to evaluate the influence of genetic polymorphisms of GSTM1 and GSTT1 gene loci in cervical carcinogenesis. The study was conducted in Lok Nayak hospital, New Delhi. DNA from clinical scrapes of 482 women with minor gynaecologic complaints attending Gynaecology OPD and tumor biopsies of 135 cervical cancer cases attending the cancer clinic was extracted. HPV DNA was detected by standard polymerase chain reaction (PCR) using L1 consensus primer pair. Polymorphisms of GSTM1 and GSTT1 were analysed by multiplex PCR procedures. Differences in proportions were tested using Pearson's Chi-square test with Odds ratio (OR) and 95% confidence interval (CI). The risk of cervical cancer was almost three times in women with GSTM1 homozygous null genotype (OR-2.62, 95%CI, 1.77-3.88; p<0.0001). No association of GSTM1 or GSTT1 homozygous null genotypes was observed in women with normal, precancerous and cervical cancerous lesions among ≤35 or >35 years of age groups. Smokers with null GSTT1 genotype had a higher risk of cervical cancer as compared to non-smokers (OR-3.01, 95% CI, 1.10-8.23; p=0.03). The results further showed that a significant increased risk of cervical cancer was observed in HPV positive smoker women with GSTT1 (OR-4.36, 95% CI, 1.27-15.03; p=0.02) and GSTM1T1 (OR-3.87, 95% CI, 1.05-14.23; p=0.04) homozygous null genotypes as compared to HPV positive non smokers. The results demonstrate that the GST null genotypes were alone not associated with the development of cervical cancer, but interacted with smoking and HPV to exert effects in our Delhi population.

Cao DL, Ye DW, Dai B, et al.
Association of glutathione S-transferase T1 and M1 polymorphisms with prostate cancer susceptibility in populations of Asian descent: a meta-analysis.
Oncotarget. 2015; 6(34):35843-50 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Genetic polymorphism was hypothesized to be reason of variation in prostate cancer incidence among different racial group. Based on that published data on the association of prostate cancer susceptibility with polymorphisms in genes encoding Glutathione S-transferases (GSTs) were inconclusive, the aim of this study was to more precisely address the role of GSTs polymorphisms (especially, GSTT1 and GSTM1 deletions) on prostate cancer risk in Asian descent.
METHODS: A meta-analysis including 8 articles with 711 cases and 1122 controls for GSTT1 and 1098 cases and 1588 controls for GSTM1 was performed.
RESULTS: Significantly increased prostate cancer risk was found among subjects carrying GSTM1 null genotype (odds ratio (OR) = 1.403; 95% confidence interval (CI) = 1.088 - 1.808) but not among subjects carrying GSTT1 deletion genotype (OR = 0.959; 95%CI = 0.709 - 1.297). When stratified by country, the null genotype of GSTT1 neither increased nor decreased prostate cancer risk significantly in China (OR = 1.355; 95%CI = 0.895 - 2.049), Japan (OR = 0.812; 95%CI = 0.545 - 1.211), and Korea (OR = 1.056; 95%CI = 0.727 - 1.534). While significant association of elevated prostate cancer risk with GSTM1 deletion were found in China (OR = 1.665; 95%CI = 1.324 - .094) and Korea (OR = 1.914; 95%CI = 1.311 - 2.793) but not in Japan (OR = 0.980; 95%CI = 0.726 - 1.321).
CONCLUSIONS: In summary, this meta-analysis suggested that the null genotype of GSTM1 rather than GSTT1 may be involved in the etiology of prostate cancer in Asian population.

Kimi L, Ghatak S, Yadav RP, et al.
Relevance of GSTM1, GSTT1 and GSTP1 Gene Polymorphism to Breast Cancer Susceptibility in Mizoram Population, Northeast India.
Biochem Genet. 2016; 54(1):41-9 [PubMed] Related Publications
The enzymes encoded by glutathione S-transferase mu 1 (GSTM1) and theta 1 (GSTT1) genes are involved in the metabolism of wide range of carcinogens that are ubiquitous in the environment. Homozygous deletions of the GSTM1 and GSTT1 genes are commonly found and result in lack of enzyme activity. This study was undertaken to evaluate the association between GSTM1, GSTT1 and GSTP1 gene polymorphism and breast cancer risk in Mizoram population. Odd ratio (OR) and 95% confidence interval (CI) from conditional logistic regression model were used to estimate the association between genetic polymorphism and breast cancer risk. The GSTM1 and GSTT1 null genotypes were associated with an increased risk of breast cancer [OR = 10.80 (95% CI 1.16-100.43)]. The risk of breast cancer associated with the GSTT1 null genotype was observed to be low among postmenopausal women. When considered together, GSTM1 and GSTT1 genotypes were found to be associated with an increased risk of breast cancer. The relationship between GSTM1 and GSTT1 gene deletions and breast cancer risk was substantially altered by consumption of Smoked Meat/Vegetable. In the present study, GSTP1Ile105Val (rs1695) polymorphism was related to breast cancer susceptibility or phenotype. Our data provides evidence for substantially increased risk of breast cancer associated with GSTM1 and/or GSTT1 homozygous gene deletions in Mizoram population.

Masood N, Mubashar A, Yasmin A
Epidemiological factors related to GSTM1 and GSTT1 genes deletion in colon and rectum cancers: A case-control study.
Cancer Biomark. 2015; 15(5):583-9 [PubMed] Related Publications
BACKGROUND: GSTM1 and GSTT1 are phase II enzymes which provide chemical defense to cells.
OBJECTIVE: This study was designed to evaluate association of GSTM1 and GSTT1 deletion along with epidemiological factors with risk of colon and rectum cancers.
METHODOLOGY: Multiplex PCR was used for cancer patients as well as age and gender matched cancer free controls.
RESULTS: Mean age of patients and controls was 45.5 (± 14.6) and 43.5 (± 18.08) years respectively. Among epidemiological factors; gender, age ≥ 50 years, active/passive smoking, naswar addiction, residential area, family history, red meat, fruit and vegetable intake showed no association with CRC (P ≥ 0.05). Symptoms of CRC like altered bowel habits (70%) was more common compared with other symptoms. GSTM1 (P ≤ 0.05) and GSTT1 (P ≤ 0.05) deletions were found to be significantly associated with CRC compared with controls. Association of epidemiological factors like gender, active/passive smoking, naswar addiction, residential area and family history were associated neither with GSTM1 deletion nor to GSTT1 deletion in both cancers (P ≥ 0.05). Significant association was present between stage III and GSTM1 (CI 95% 0.15-1.39) as well as GSTT1 (CI 95% 0.14-2.44) deletion in CRC.
CONCLUSION: These results suggest that GSTM1 and GSTT1 deletion were associated with increased risk of colon and rectum cancer in Pakistani population.

Liu R, Zhao X, Liu X, et al.
Influences of ERCC1, ERCC2, XRCC1, GSTP1, GSTT1, and MTHFR polymorphisms on clinical outcomes in gastric cancer patients treated with EOF chemotherapy.
Tumour Biol. 2016; 37(2):1753-62 [PubMed] Related Publications
This study investigated the associations between genetic polymorphisms of six genes involved in DNA repair, detoxification pathways, and fluoropyrimidine metabolism and clinical outcomes in MGC patients receiving EOF treatment. This retrospective study included 108 Chinese MGC patients receiving EOF as first-line chemotherapy. Nine single nucleotide polymorphisms (SNPs) of six genes (ERCC1 rs2298881, ERCC2 rs13181 and rs1799793, XRCC1 rs25487 and rs25489, GSTP1 rs1695, GSTT1 rs2266637, and MTHFR rs1801133 and rs1801131) were genotyped, and the associations between each SNP and clinical outcome were analyzed. XRCC1 rs25487 A allele was significantly associated with progression disease (PD) to EOF (p = 0.002), and patients with AA genotype had significantly poorer progression-free survival (PFS) (p = 0.001) and overall survival (OS) (p = 0.041) compared with patients with the G allele (GG + GA). ERCC2 rs13181 G allele was significantly associated with PD (p = 0.026), and G carriers (GG + GT) tended to have poorer PFS (p = 0.092) than TT homozygotes. ERCC2 rs1799793 GA genotype was associated with unfavorable PFS (p = 0.034) and a tendency toward poorer OS (p = 0.090) compared with GG homozygotes. Patients were categorized as either good (0 risk factors) or poor risk (≥1 unfavorable SNPs) using a prognostic index based on XRCC1 rs25487 AA, ERCC2 rs13181 (GG + GT), and ERCC2 rs1799793 GA genotypes, with median OS and PFS of 534 days, 281 days (p = 0.009) and 206 days, and 123 days (p < 0.001), respectively. These results suggest that the prognostic index comprising XRCC1 rs25487, ERCC2 rs13181, and rs1799793 polymorphisms may be a useful predictor of clinical outcomes in MGC treated with EOF.

Hsu LI, Wu MM, Wang YH, et al.
Association of Environmental Arsenic Exposure, Genetic Polymorphisms of Susceptible Genes, and Skin Cancers in Taiwan.
Biomed Res Int. 2015; 2015:892579 [PubMed] Free Access to Full Article Related Publications
Deficiency in the capability of xenobiotic detoxification and arsenic methylation may be correlated with individual susceptibility to arsenic-related skin cancers. We hypothesized that glutathione S-transferase (GST M1, T1, and P1), reactive oxygen species (ROS) related metabolic genes (NQO1, EPHX1, and HO-1), and DNA repair genes (XRCC1, XPD, hOGG1, and ATM) together may play a role in arsenic-induced skin carcinogenesis. We conducted a case-control study consisting of 70 pathologically confirmed skin cancer patients and 210 age and gender matched participants with genotyping of 12 selected polymorphisms. The skin cancer risks were estimated by odds ratio (OR) and 95% confidence interval (CI) using logistic regression. EPHX1 Tyr113His, XPD C156A, and GSTT1 null genotypes were associated with skin cancer risk (OR = 2.99, 95% CI = 1.01-8.83; OR = 2.04, 95% CI = 0.99-4.27; OR = 1.74, 95% CI = 1.00-3.02, resp.). However, none of these polymorphisms showed significant association after considering arsenic exposure status. Individuals carrying three risk polymorphisms of EPHX1 Tyr113His, XPD C156A, and GSTs presented a 400% increased skin cancer risk when compared to those with less than or equal to one polymorphism. In conclusion, GSTs, EPHX1, and XPD are potential genetic factors for arsenic-induced skin cancers. The roles of these genes for arsenic-induced skin carcinogenesis need to be further evaluated.

Mansoori AA, Jain SK
Molecular Links between Alcohol and Tobacco Induced DNA Damage, Gene Polymorphisms and Patho-physiological Consequences: A Systematic Review of Hepatic Carcinogenesis.
Asian Pac J Cancer Prev. 2015; 16(12):4803-12 [PubMed] Related Publications
Chronic alcohol and tobacco abuse plays a crucial role in the development of different liver associated disorders. Intake promotes the generation of reactive oxygen species within hepatic cells exposing their DNA to continuous oxidative stress which finally leads to DNA damage. However in response to such damage an entangled protective repair machinery comprising different repair proteins like ATM, ATR, H2AX, MRN complex becomes activated. Under abnormal conditions the excessive reactive oxygen species generation results in genetic predisposition of various genes (as ADH, ALDH, CYP2E1, GSTT1, GSTP1 and GSTM1) involved in xenobiotic metabolic pathways, associated with susceptibility to different liver related diseases such as fibrosis, cirrhosis and hepatocellular carcinoma. There is increasing evidence that the inflammatory process is inherently associated with many different cancer types, including hepatocellular carcinomas. The generated reactive oxygen species can also activate or repress epigenetic elements such as chromatin remodeling, non-coding RNAs (micro-RNAs), DNA (de) methylation and histone modification that affect gene expression, hence leading to various disorders. The present review provides comprehensive knowledge of different molecular mechanisms involved in gene polymorphism and their possible association with alcohol and tobacco consumption. The article also showcases the necessity of identifying novel diagnostic biomarkers for early cancer risk assessment among alcohol and tobacco users.

Jaramillo-Rangel G, Ortega-Martínez M, Cerda-Flores RM, Barrera-Saldaña HA
Polymorphisms in GSTM1, GSTT1, GSTP1, and GSTM3 genes and breast cancer risk in northeastern Mexico.
Genet Mol Res. 2015; 14(2):6465-71 [PubMed] Related Publications
Glutathione S-transferases (GSTs) are a family of phase II metabolizing enzymes involved in carcinogen detoxification and the metabolism of various bioactive compounds. Several genes that code for these enzymes are polymorphic in an ethnicity-dependent manner, with particular genotypes previously associated with an increased risk of breast cancer. The purpose of this study was to determine the frequencies of polymorphisms in the genes GSTM1, GSTT1, GSTP1, and GSTM3 and to investigate whether an association exists between these genes and breast cancer risk in subjects from northeastern Mexico. Genotypes were determined for 243 women with histologically confirmed breast cancer and 118 control subjects. Gene polymorphisms were analyzed using a DNA microarray. We found an increased breast cancer risk associated with the GSTM1 gene deletion polymorphism (OR = 2.19; 95%CI = 1.50-3.21; P = 0.001). No associations between the GSTT1, GSTP1, and GSTM3 genotypes and neoplasia risk were observed. In conclusion, we determined the genotype distribution of GST polymorphisms in control subjects and breast cancer patients from northeastern Mexico. The GSTM1 null genotype was associated with breast cancer risk. Our findings may be used to individualize breast cancer screening and therapeutic intervention in our population, which displays ethnic characteristics that differentiate it from other populations in Mexico.

Lopes BA, Emerenciano M, Gonçalves BA, et al.
Polymorphisms in CYP1B1, CYP3A5, GSTT1, and SULT1A1 Are Associated with Early Age Acute Leukemia.
PLoS One. 2015; 10(5):e0127308 [PubMed] Free Access to Full Article Related Publications
Based on observational studies, early age leukemia (EAL) was associated with maternal hormone exposure during pregnancy. We studied the association between genetic polymorphisms of estrogen metabolism and EAL. Using data from the Brazilian Collaborative Study Group of Infant Acute Leukemia (2000-2012), 350 cases and 404 age-matched controls and 134 mothers of cases and controls were genotyped to explore polymorphisms in genes of the estrogen metabolism pathway: CYP1B1 (c.1294C>G, rs1056836), CYP3A4 (c.-392A>G, rs2740574), CYP3A5 (c.219-237G>A, rs776746), GSTM1/GSTT1 deletions, and SULT1A1 (c.638G>A, rs9282861; and c.667A>G, rs1801030). Logistic regression was used to calculate the odds ratios (OR) with 95% confidence intervals (CIs), and unconditional logistic regression was used to estimate adjusted odds ratios (aORs) by ethnicity. Because of multiple testing, p values < 0.01 were significant after Bonferroni correction. SULT1A1 (c.638G>A) was associated to infant acute lymphoblastic leukemia and acute myeloid leukemia (AML) risk in males (additive model: aOR = 0.52; 95% CI: 0.29-0.95, p = 0.03; dominant model: aOR = 2.18; 95% CI: 1.17-4.05, p = 0.01, respectively). CYP1B1 polymorphism was associated with a decreased risk of AML either for non-white or female children (additive model: OR = 0.24; 95% CI: 0.08-0.76, p < 0.01; additive model: aOR = 0.27; 95% CI: 0.08-0.89, p = 0.03, respectively). Since polymorphisms of Cytochrome P450 genes presented gender-specific risk associations, we also investigated their expression. CYP1B1 was not expressed in 57.1% of EAL cases, and its expression varied by genotype, gender, and leukemia subtype. Maternal-fetal GSTT1 null genotype was associated with risk of EAL. This study shows that polymorphisms in genes of estrogen metabolism confer genetic susceptibility to EAL, mainly in males, and maternal susceptibility genes modify the risk for developing EAL in newborns.

Lopes-Aguiar L, Visacri MB, Nourani CM, et al.
Do genetic polymorphisms modulate response rate and toxicity of Cisplatin associated with radiotherapy in laryngeal squamous cell carcinoma?: a case report.
Medicine (Baltimore). 2015; 94(16):e578 [PubMed] Free Access to Full Article Related Publications
UNLABELLED: Cisplatin (CDDP) plus radiotherapy (RT) has been used to treat advanced laryngeal squamous cell carcinoma (LSCC) patients. Single nucleotide polymorphisms (SNPs) may be responsible for differences in chemo/radiosensitivity and side effects in those patients. We reported an advanced LSCC patient, who obtained durable complete response and unexpected pronounced toxicity during CDDP and RT, possibly due to SNPs in genes that modulate the effects of this therapeutic modality.
CASE PRESENTATION: A 30-year-old man with advanced LSCC obtained durable complete response and severe alopecia and pancytopenia after standard and reduced doses of CDDP and RT. Analyses of SNPs revealed that the patient presented GSTT1 deletion, variant MSH3 1045ThrThr, wild GSTP1 105IleIle, and wild BAX -248GG genotypes, which were previously described in association with abnormal detoxification, DNA repair, and damaged cell apoptosis, respectively. Seven other advanced LSCC patients with GSTT1 gene, MSH3 AlaAla or AlaThr, GSTP1 IleVal or ValVal, and BAX GA or AA genotypes served as controls of the study. Only 1 control presented complete response; the other 6 controls obtained partial response of short duration. Four and 3 controls presented grade 1 or 2 and grade 3 anemia or leukopenia during treatment, respectively. The CDDP level in urine collected after CDDP infusion in the reported patient was lower than the median value obtained in controls, suggesting a higher amount of intracellular CDDP in the reported case.The data suggest, for the first time, that inherited abnormalities in intracellular detoxification of CDDP, DNA repair of lesions induced by CDDP and RT, and damaged cell apoptosis may alter treatment response and toxicity in LSCC, but should be confirmed by large pharmacogenomic studies.

Zhunussova G, Zhunusbekova B, Djansugurova L
Association between glutathione S-transferase M1 and T1 polymorphisms and colorectal cancer risk in patients from Kazakhstan.
Clin Lab. 2015; 61(1-2):161-8 [PubMed] Related Publications
BACKGROUND: Colorectal cancer (CRC) is one of the most common malignancies worldwide and the incidence is increasing in developed as well as developing countries including Kazakhstan. Glutathione S-transferases (GSTs) are considered to be cancer susceptibility genes as they play a role in the detoxification of carcinogenic species. In this case-control study the influence of GSTM1 and GSTT1 polymorphisms on CRC risk in Kazakhstan population were evaluated.
METHODS: Blood samples were collected from patients diagnosed with rectal or colon cancer (300 individuals) as well as a control cohort of healthy volunteers (300 individuals), taking into account the age, gender, ethnicity, and smoking habits of the CRC patients. Deletion polymorphisms were genotyped employing a multiplex PCR amplification method. Association between polymorphisms and CRC susceptibility risk was calculated using multivariate analysis and logistic regression for odd ratio (OR).
RESULTS: The homozygous GSTM1 null genotype was associated with significantly increased risk of CRC (OR = 2.01, 95% CI = 1.45-2.79, p = 0.0001) while the homozygous GSST1 null genotype was not associated with the risk of developing CRC (OR = 1.10, 95% CI = 0.78-1.55, p = 0.001), but the heterozygous genotype correlated with CRC susceptibility (OR = 1.98, 95% CI = 1.30-3.00, p = 0.001). Also, separate analyses of each of the main ethnic groups (Kazakh and Russian) showed a strong association of GSTM1 null genotype with CRC risk (for Kazakhs OR = 2.36, 95% CI = 1.35-4.10, p = 0.006 and for Russians OR = 1.84, 95% CI = 1.17-2.89, p = 0.003). The CRC risk of GSTM1 null genotype in smokers was considerably higher (OR = 3.37, 95% CI = 1.78-6.38, p = 0.0007). The combination of the GSTM1 and GSTT1 null genotypes in combined mixed population of Kazakhstan showed a trend to increasing the risk of developing CRC (OR = 1.60, 95% CI = 1.00-2.56), but it was not statistically significant.
CONCLUSIONS: In conclusion, the results of this case-control study for sporadic cases of CRC show that GSTM1 deletion polymorphisms can have predictive value for susceptibility to CRC (OR = 2.01, p = 0.0001) for the mixed population from Kazakhstan and for both main ethnic groups (Kazakhs and Russians (OR = 2.36 and OR = 1.84, respectively)).

Weich N, Nuñez MC, Galimberti G, et al.
Polymorphic variants of GSTM1, GSTT1, and GSTP1 genes in childhood acute leukemias: A preliminary study in Argentina.
Hematology. 2015; 20(9):511-6 [PubMed] Related Publications
BACKGROUND AND AIM: Despite recent major advances in leukemia research, the etiopathogenesis of childhood leukemias remains far elusive. Individual predisposing factors, including polymorphisms in detoxification enzymes, have been implicated in the molecular pathogenesis and heterogeneity of the disease. Genetic polymorphisms of glutathione S-transferases (GSTs) that alter enzyme activity could be an additional factor that increases the risk of acute leukemia, but data are lacking in Argentina. We assessed the association of GST polymorphisms and the susceptibility to childhood leukemia in Argentina by conducting an exploratory case-control study and correlated patients' genotype to clinical and biological features.
METHODS: Deletion polymorphisms in GSTM1 and GSTT1 genes and the single nucleotide polymorphism in GSTP1 c.313A>G (rs1695; p.105Ile>Val) were genotyped by PCR-RFLP in 36 patients and 133 healthy individuals.
RESULTS: GSTM1-null genotype was associated with a lower risk of developing acute leukemia (P = 0.013; OR: 0.31; CI: 0.12-0.80), while GSTP1-GG variants displayed an increased risk (P = 0.01; OR: 3.9; CI: 1.85-8.2). However, no differences were found for GSTT1 gene. Conclusion These preliminary results, to be validated in a larger population from Argentina, suggest that the development of pediatric leukemia may be differentially influenced by polymorphic variants in GST genes.

Zakiullah, Ahmadullah, Khisroon M, et al.
Genetic susceptibility to oral cancer due to combined effects of GSTT1, GSTM1 and CYP1A1 gene variants in tobacco addicted patients of Pashtun ethnicity of Khyber Pakhtunkhwa province of Pakistan.
Asian Pac J Cancer Prev. 2015; 16(3):1145-50 [PubMed] Related Publications
Associations of GSTT1, GSTM1 and CYP1A1 gene variants with risk of developing oral cancer were evaluated in this study. A case-control study was conducted in Pashtun population of Khyber Pakhtunkhwa province of Pakistan in which 200 hospital based oral cancer cases and 151 population based healthy controls exposed to similar environmental conditions were included. Sociodemographic data were obtained and blood samples were collected with informed consent for analysis. GSTM1 and GSTT1 were analysed through conventional PCR method while specific RT-PCR method was used to detect CYP1A1 polymorphisms. Results were analyzed for conditional logistic regression model by SPSS version 20. The study shows that patients with either GSTM1 or GSTT1 null genotypes have significantly higher risk of oral cancer (adjusted odds (OR): (3.019 (1.861-4.898) and 3.011(1.865-4.862), respectively), which further increased when either one or both null genes were present in combination (adjusted odds (OR): (3.627 (1.981-6.642 and 9.261 (4.495-19.079), respectively). CYP1A1 rs4646903 gene variants individually showed weak association OR: 1.121 (0.717-1.752); however, in the presence of GSTM1 and/or GSTT1 null genotypes further increasing the association (adjusted odds (ORs): 4.576 (2.038-10.273), 5.593 (2.530-12.362) and 16.10 (3.854-67.260 for GSTM/GSTT null and CYP1A1 wild type, GSTM/GSTT either null and CYP1A1 variant alleles, and all 3 gene polymorphisms combinations, respectively). Our findings suggest that presence of GSTM1 and/or GSTT1 null genotypes along with variant alleles of CYP1A1 may be the risk alleles for oral cancer susceptibility in Pashtun population.

Disclaimer: This site is for educational purposes only; it can not be used in diagnosis or treatment.

Cite this page: Cotterill SJ. GSTT1, Cancer Genetics Web: Accessed:

Creative Commons License
This page in Cancer Genetics Web by Simon Cotterill is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.
Note: content of abstracts copyright of respective publishers - seek permission where appropriate.

 [Home]    Page last revised: 13 March, 2017     Cancer Genetics Web, Established 1999