Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:2.5.1.18 (glutathione S-transferase)
22,582 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Both genetic and environmental factors are involved in the development of cancer; some phase I and II enzymes involved in the metabolism of carcinogens are polymorphic in genotypes. This case-control study focused on the interactions between oral cancer risk factors and genetic polymorphisms of cytochrome P-450 (CYP) 2E1 and glutathione S-transferase (GST) M1 and GSTT1. A total of 41 male oral cancer cases was recruited from National Taiwan University Hospital, and 123 healthy controls frequency-matched on ethnicity, sex, and age were recruited from residents living in Taipei City and Taipei County. History of cigarette smoking, alcohol drinking, and betel quid chewing was obtained through a standardized questionnaire interview, and genotypes of CYP2E1, GSTM1, and GSTT1 were determined by PCR. Cigarette smoking, alcohol drinking, and betel quid chewing were significantly associated with the risk of oral cancer in a dose-response relationship. All betel quid chewers smoked cigarettes in both the case and control groups. In the multiple logistic regression analysis, those who had null genotypes of GSTM1 and/or GSTT1 had an increased oral cancer risk compared with those who had non-null genotypes of both GSTM1 and GSTT1, showing a multivariate-adjusted odds ratio (OR) of 4.6 with a 95% confidence interval (CI) of 0.9-23.7 (P = 0.08). The CYP2E1 c1/c2 and c2/c2 genotypes were associated with a significantly increased oral cancer risk compared with the c1/c1 genotype among those who did not chew betel quid (OR, 4.7; 95% CI, 1.1-20.2), but not among betel quid chewers. Habitual alcohol drinking was associated with a significantly increased oral cancer risk, showing an OR of 3.0 (95% CI, 1.1-8.8). These results implied that there are gene-gene and gene-environment interactions in the development of oral cancer.
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PMID:Genetic polymorphisms of CYP2E1, GSTM1, and GSTT1; environmental factors and risk of oral cancer. 936 63

The A/G polymorphism at nucleotide 313 in the glutathione S-transferase P1-1 (GSTP1) gene was examined in patients with different types of smoking-related cancers (oral, lung, gastric, colorectal and urothelial cancers) and healthy control individuals. This polymorphism results in an amino acid substitution from isoleucine to valine at residue 105, which reduces catalytic activity of the enzyme. In control individuals, 23.8% of individuals had GSTP1 AG or GG genotype. This rose to 37.3% [n = 83, odds ratio = 1.93 (1.05-3.58), P = 0.035] in oral cancer patients. No increase in the frequency of the GSTP1 AG or GG genotype was obtained in lung, gastric, colorectal or urothelial cancers in this Japanese population. After grouping by smoking status, no consistent difference was observed between smoking patients and corresponding control individuals for the frequency of the GSTP1 A/G polymorphism for any cancer. However, a moderate risk (odds ratio = 2.78; 95% confidence interval 1.06-7.51) was associated with this polymorphism in the non-smoking group of oral cancer patients. The results suggest the GSTP1 polymorphism at nucleotide 313 may be associated with susceptibility to oral squamous cell carcinoma in the Japanese population.
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PMID:Human glutathione S-transferase P1 polymorphism and susceptibility to smoking related epithelial cancer; oral, lung, gastric, colorectal and urothelial cancer. 1037 63

Two members of the mu class of glutathione S-transferase (GST) genes, GSTM1 and GSTM3, have polymorphic alleles which have been associated with altered levels of GST mu protein expression and may be linked to increased risk for several tobacco-related cancers. Oral cancer is a tobacco-related disease that affects African-American men at a significantly higher incidence than Caucasian men. To examine the potential role of GSTM polymorphisms in risk for oral cancer in African-Americans and Caucasians, the prevalences of the GSTM1 null and GSTM3 intron 6 polymorphisms were examined in 63 African-American and 101 Caucasian patients with histologically confirmed primary oral cancer, as well as in 133 African-American and 213 Caucasian matched control subjects. In African-Americans, the odds ratio for oral cancer associated with the GSTM1 (0/0) genotype was 3.1 [95% confidence interval (CI) = 1.1-8.5], with the association between the GSTM1 (0/0) genotype and oral cancer risk strongest in heavy smokers [i.e. > 24 pack-years; odds ratio (OR) = 5.4, 95% CI = 1.2-24]. Using the potentially most protective GSTM1 [+]/GSTM3 (B/B) genotype as the reference group, increased risk for oral cancer was observed in African-Americans with the GSTM1 [+]/GSTM3 [(A/A) + (A/B)] (OR = 2.2, 95% CI = 0.82-6.0), GSTM1 (0/0)/GSTM3 (B/B) (OR = 4.3, 95% CI = 1.1-16), and GSTM1 (0/0)/GSTM3 [(A/A) + (A/B)] (OR = 6.6, 95% CI = 1.2-38) genotypes (P < 0.01, trend test). No significant associations were observed between GSTM genotype and oral cancer risk in Caucasians. These results suggest that the GSTM1 null and GSTM3 intron 6 polymorphisms play an important role in risk for oral cancer among African-Americans and implicates the mu class of GSTs as important tobacco carcinogen detoxifying enzymes in this population.
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PMID:Comparison of GSTM polymorphisms and risk for oral cancer between African-Americans and Caucasians. 1076

Polymorphisms in the gene encoding the glutathione S-transferase (GST) pi metabolizing enzyme have previously been associated with susceptibility to various cancers. In this study, the importance of GSTP1 genotypes as determinants of risk for oral cancer was assessed by examining the prevalence of GSTP1 alleles in 157 incident oral cancer cases and 260 non-cancer control individuals frequency-matched by race, sex, and age at diagnosis (+/- 5 years). The GSTP1*A, GSTP1*B, GSTP1*C, and GSTP1*D alleles were elucidated by polymerase chain reaction-restriction fragment length polymorphism analysis of polymorphisms present in codons 105 (isoleucine:valine) and 114 (alanine:valine) of the GSTP1 gene. Increased risk for oral cancer was observed in individuals who were homozygous for any combination of GSTP1 polymorphic alleles (i.e. *B, *C, and/or *D alleles; odds ratio = 2.4, 95% confidence interval = 1.2-4.8). Similar risk was observed in both Caucasians (odds ratio = 2.6, 95% confidence interval = 1.1-6.2) and African-Americans (odds ratio = 2.3, 95% CI = 0.68-7.5). A greater risk was observed in individuals with the GSTP1 (Var/Var) genotype who were exposed to low levels of smoking (i.e. < or = 20 pack-years [py], odds ratio = 3.4, 95% confidence interval = 1.1-11) than among heavier smokers (i.e. > 20 pack-years [py], odds ratio = 1.4, 95% confidence interval = 0.48-4.0). These results suggest that GSTP1 genotype may play a role in risk for oral cancer particularly among lighter smokers.
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PMID:Association between glutathione S-transferase pi genetic polymorphisms and oral cancer risk. 1078 Feb 69

We investigated 191 patients with oral cancer (121 males and 70 females) and 121 non oral cancer patients (69 males and 52 females), both groups with a history of alcohol use. Blood was analyzed with aldehyde dehydrogenase 2 (ALDH 2) and glutathione S-transferase M 1 (GSTM 1) genotyping. ALDH 2 genotyping was performed by polymerase chain reaction (PCR)-Restriction fragment length polymorphism (RFLP) method and GSTM 1 genotyping was amplified with PCR using GSTM 1 specific primers. In the oral cancer group, the alcohol-drinking rate (59.7%) was significantly higher than in the non cancer group (alcohol-drinking rate 27.3%, p < 0.01). The incidence of inactive ALDH 2 and GSTM 1 in the cancer group with an alcohol-drinking habit was 34.2 and 67.5% and was higher than in the non cancer group with an alcohol-drinking habit (15.1, 45.5%).
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PMID:Aldehyde dehydrogenase 2 and glutathione S-transferase M 1 polymorphisms in relation to the risk for oral cancer in Japanese drinkers. 1088 18

Radical scavengers play an important role in cancer cells defending themselves against free radicals which occur with irradiation. SOD (Cu,Zn, Mn-) and GST-pi are radical scavengers with an effect on radiation therapy. We investigated the correlation between radiation effects and expression of Cu,Zn-, Mn-SOD and GST-pi in 34 cases of oral cancer, treated with preoperative radiation therapy. In this study, 22 cases out of 34 were classified as effective and 12 cases as non-effective. Expression of Cu,Zn, Mn-SOD and GST-pi were observed in 13 (38.2%), 10 (29.4%) and 20 (58.8%) cases, respectively. Regarding the value of radiation sensitivity from expression of these proteins in the biopsy samples, no significant correlation was found between those expressions and histological effectiveness of preoperative radiation therapy. But interestingly, in 11 out of 12 of the non-effective cases, strong staining of Cu, Zn-SOD and GST-pi were shown at the residual cancer cells after preoperative radiation therapy. These results suggested that the expression of SOD (Cu,Zn-, and Mn-) and GST-pi may be not useful markers for predicting the effects of radiation therapy. However, Cu, Zn-SOD and GST-pi were increased by irradiation and may play an important role in radiation resistance and cancer cell regeneration after radiation therapy.
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PMID:Expression of Cu,Zn-SOD, Mn-SOD and GST-pi in oral cancer treated with preoperative radiation therapy. 1094 48

Squamous cell carcinoma of the head and neck (SCCHN) is a group of cancers of epithelial origin that may provide an ideal model for the study of gene-environment interaction. SCCHN includes squamous cell carcinomas of the oral cavity, pharynx, and larynx. Approximately 90% of the attributable risk for oral cancer and 80% of the attributable risk for larynx cancer results from tobacco use. Tobacco smoking has been demonstrated to increase the risk of SCCHN in a dose-response fashion. Polymorphisms of carcinogen-metabolizing enzymes, known to be involved in metabolism of carcinogens found in tobacco smoke, are relatively common in most populations. This paper provides a concise review of the 24 published studies that evaluated the risk of SCCHN in relation to two deletion polymorphisms of the glutathione S-transferase family: GSTM1 and GSTT1. Patterns of risk based on the site of the tumor and on nationality are presented, as are some methodological weaknesses of the studies. The results of these studies are inconsistent, with some reporting weak-to-moderate associations and others finding no elevation in risk for the main effect of the gene. Few studies have directly evaluated the interaction with tobacco. Well-designed, population-based studies of adequate size are needed.
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PMID:GSTM1, GSTT1, and the risk of squamous cell carcinoma of the head and neck: a mini-HuGE review. 1144 41

Areca quid chewing has been linked to oral submucous fibrosis and oral cancer. Arecoline, a major areca nut alkaloid, is considered to be the most important etiologic factor in the areca nut. In order to elucidate the pathobiological effects of arecoline, cytotoxicity assays, cellular glutathione S-transferase (GST) activity and lipid peroxidation assay were employed to investigate cultured human buccal mucosal fibroblasts. To date, there is a large proportion of areca quid chewers who are also smokers. Furthermore, nicotine, the major product of cigarette smoking, was added to test how it modulated the cytotoxicity of arecoline. At a concentration higher than 50 microg/ml, arecoline was shown to be cytotoxic to human buccal fibroblasts in a dose-dependent manner by the alamar blue dye colorimetric assay (P<0.05). In addition, arecoline significantly decreased GST activity in a dose-dependent manner (P<0.05). At concentrations of 100 microg/ml and 400 microg/ml, arecoline reduced GST activity about 21% and 46%, respectively, during a 24 h incubation period. However, arecoline at any test dose did not increase lipid peroxidation in the present human buccal fibroblast test system. The addition of extracellular nicotine acted synergistically on the arecoline-induced cytotoxicity. Arecoline at a concentration of 50 microg/ml caused about 30% of cell death over the 24 h incubation period. However, 2.5 mM nicotine enhanced the cytotoxic response and caused about 50% of cell death on 50 microg/ml arecoline-induced cytotoxicity. Taken together, arecoline may render human buccal mucosal fibroblasts more vulnerable to other reactive agents in cigarettes via GST reduction. The compounds of tobacco products may act synergistically in the pathogenesis of oral mucosal lesions in areca quid chewers. The data presented here may partly explain why patients who combined the habits of areca quid chewing and cigarette smoking are at greater risk of contracting oral cancer.
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PMID:Synergistic effects of nicotine on arecoline-induced cytotoxicity in human buccal mucosal fibroblasts. 1154 36

This study evaluates the influence of genetic polymorphism at GSTM1, GSTM3 and GSTT1 gene loci on oral cancer risk among Indians habituated to the use of, smokeless tobacco, bidi or cigarette. DNA extracted from white blood cells of 297 cancer patients and 450 healthy controls by the proteinase K phenol-chloroform extraction procedure were analyzed by the polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism (RFLP) analyses. Lifetime tobacco exposure was evaluated as a risk factor in relation to the polymorphism at the GST gene loci using logistic regression analysis. There was no significant difference in the distribution of the GSTM3 and GSTT1 genotypes between oral cancer patients and controls. In contrast, a significant 3-fold increase in risk was seen for patients with the GSTM1 null genotype (age adjusted OR = 3.2, 95% CI 2.4-4.3). The impact of the GSTM1 null genotype on oral cancer risk was also analyzed in separate groups of individuals with different tobacco habits. The odds ratio associated with the GSTM1 null genotype was 3.7 (95% CI 2.0-7.1) in tobacco chewers, 3.7 (5% CI 1.3-7.9) in bidi smokers and 5.7 (95% CI 2.0-16.3) in cigarette smokers. Furthermore, increased lifetime exposure to chewing tobacco appeared to be associated with a 2-fold increase in oral cancer risk in GSTM1 null individuals. The results suggest that the GSTM1 null genotype is a risk factor for development of oral cancer among Indian tobacco habitues.
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PMID:Polymorphism at GSTM1, GSTM3 and GSTT1 gene loci and susceptibility to oral cancer in an Indian population. 1201 53

Environmental carcinogen exposures contribute to the development of oral cancer and improved test systems for the analysis of such carcinogens are needed. We have previously isolated and characterized an epithelial cell line from the tongue of a BigBlue rat. Now, we have established an immortalized fibroblast cell line from the same organ. We exposed these cells to 4-nitroquinoline-1-oxide (NQO), a well-known experimental oral carcinogen in the rat and other species, and measured its cytotoxic and genotoxic (cII transgene mutagenesis) effects. Both cell lines were very sensitive to NQO toxicity and showed dose-dependent mutant frequency responses. At the highest NQO dose tested, 70 ng/ml, the mutant frequency was elevated more than eight-fold above background for the epithelial cells and more than 25-fold for the fibroblast cells. We examined cellular parameters which could affect glutathione-dependent detoxication of mutagens. Glutathione (GSH) contents of the two cell lines were similar. Glutathione transferase (GST) activities were measured with several substrates and were generally higher in the epithelial cells. Although multiple biochemical and biological characteristics of individual cell lines are likely to determine responses to mutagens, the greater sensitivity of the fibroblast cells to NQO mutagenicity is in accord with the lower GST activity and the lower DNA content of these cells. These new cell lines are suitable for in vitro testing of chemicals as possible oral mutagens and for studies of their biochemical mechanisms of action.
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PMID:Mutagenicity of the oral carcinogen 4-nitroquinoline-1-oxide in cultured BigBlue rat tongue epithelial cells and fibroblasts. 1251 16


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