GSTP1 Ile105Val Polymorphism Research Articles

Ile105Val polymorphism in the GSTP1 gene is associated with susceptibility to acute myeloid leukemia: an updated systematic review and meta-analysis

Background and Objective Several genetic variations are associated with acute myeloid leukemia (AML) susceptibility, including the GSTP1 Ile105Val polymorphism. Even with the existing meta-analysis conducted on the topic, no consensus has been reached since none of the studies available performed in-depth data analysis. Hence, we performed an updated systematic review and meta-analysis in this paper to obtain more precise estimates. Materials and Methods We searched various databases and calculated the odds ratio (OR) and 95% confidence interval (CI) to examine whether the GSTP1 Ile105Val polymorphism is associated with AML susceptibility. Further statistical analysis was also done to obtain more accurate and reliable findings. Results A total of 15 studies are included in the systematic review, but only 9 were included in the meta-analysis due to the studies deviating from the Hardy-Weinberg equilibrium. The analysis showed significantly increased susceptibility to AML in the allelic, co-dominant, and recessive models. Furthermore, subgroup analysis noted increased AML susceptibility in the non-Asian population. Comparing the proportions of the genotypes and alleles showed a significantly higher proportion of the Val/Val genotype and Val allele in the non-Asian cohort. Conclusion The GSTP1 Ile105Val polymorphism is significantly associated with AML susceptibility, especially among non-Asians. Further investigation should be performed to strengthen the current results.

Interactive associations of eczema with glutathione S-transferase genes in relation to autism spectrum disorder and its severity in Jamaican children

BackgroundComorbidity of eczema withith autism spectrum disorder (ASD) is increasing. We investigated the associations of eczema and its possible interaction with polymorphisms in glutathione S-transferase (GST) genes in relation to ASD and ASD severity. MethodUsing data from 344 1:1 age- and sex-matched ASD cases and typically developing controls, we assessed additive and interactive associations of eczema with GST genes in relation to ASD by applying conditional logistic regression models, and in relation to ASD severity in ASD cases as measured by the Autism Diagnostic Observation Schedule-2nd Edition (ADOS-2) total and domain-specific comparison scores (CSs) by fitting general linear models. ResultsAfter adjusting for child’s age and history of breastfeeding, eczema had no additive association with ASD [Matched Odds ratio (MOR) and 95 % Confidence Intervals (CI): 1.04 (0.76, 1.41), P = 0.82] or ASD severity (all P > 0.20). Using a recessive genetic model, eczema was significantly associated with ASD only among children with the Val/Val genotype for the GSTP1 Ile105Val polymorphism [MOR (95 % CI) = 2.04 (1.02, 4.08), P = 0.04, P for interaction = 0.03]. In addition, among ASD cases with the GSTM1 DD genotype, those with eczema had a marginally significant higher mean ADOS-2 Social Affect CS than those without eczema (7.3 vs. 6.8, P = 0.08, P for interaction = 0.09). ConclusionOur findings suggest children with certain genotypes for GST genes may be more susceptible for comorbidity of eczema and ASD, which is consistent with the role of GST genes in both conditions.

Are there sex differences in interactive associations of environmental exposure to Lead (Pb), Mercury (Hg), and Manganese (Mn) with GST Genes (GSTP1, GSTT1, and GSTM1) in relation to ASD in Jamaican children?

BackgroundMale preponderance is well-established in children with autism spectrum disorder (ASD). Glutathione S-transferase (GST) genes play a crucial role in suppressing oxidative stress triggered by environmental stressors. ObjectiveTo determine whether the association between metals and ASD differs by sex and by GST genes. MethodsUsing data from 344 pairs of sex-and age-matched cases and controls, we assessed the association of each metal with ASD or ASD severity, by applying conditional logistic regression (CLR) or general linear models (GLM). Sex was assessed as an effect modifier in separate GST genetic models. ResultsFor Pb exposure, using a recessive model for the GSTP1 Ile105Val polymorphism, CLR revealed significant overall interaction between sex and GSTP1 (P = 0.04). However, sex-specific matched odds ratios revealed marginally lower odds of the Val/Val genotype among ASD cases than controls in females (MORfemales= 0.23 (95 % CI): 0.05–1.11, P = 0.06), but not among males (MORmales= 1.18 (95 % CI): 0.66–2.16, P = 0.57) in the adjusted model. GLMs for Hg exposure detected significant overall interactions in GSTP1 co-dominant and recessive genetic models. For example, the mean difference in ASD severity among children with Val/Val genotype compared to those with Ile/Ile or Ile/Val were MORfemales= −0.26 and MORmales= 1.30, respectively, in the adjusted model. ConclusionThe association of Pb and Hg with ASD significantly differed by sex under the GSTP1 co-dominant and recessive genetic models. Such findings reflect potential sex differences in metal detoxification mechanisms. Replication is warranted due to the limited sample size of female participants.

Association of GSTT1, GSTM1 and GSTP1 (Ile105Val) mRNA Expression with Cardiometabolic Risk Parameters in Women with Breast Cancer and Comorbidities

Breast cancer (BC) and cardiometabolic diseases share a multifactorial and modifiable etiology, modulated by complex molecular pathways. Glutathione S-transferase (GST) plays a critical role, providing protection against xenobiotics and regulating levels of enzymes and proteins in the cell. GST variants have a significant impact on susceptibility to diseases whose pathogenesis involves oxidative stress, as is the case in many inflammatory diseases such as BC and cardiometabolic pathologies. However, the expression of these polymorphic variants has not been studied in BC. This study aimed to evaluate the presence of GST mRNA isoforms and their association with clinical and cardiometabolic parameters in women with BC. This was a case-control study, and a total of 57 participants were recruited. Concentrations of glucose and lipids in blood were measured in all the participants. GST variants (GSTT1, GSTM1 and GSTP1 Ile105Val polymorphism) were evaluated in all the participants by real-time PCR analysis. There was a significant association (p < 0.05) between the frequency of GSTP1 and LDL-c in the BC group. However, the control group showed significant associations between blood pressure with GSTT1 and GSTP1 variants with total cholesterol (TC), LDL-c, VLDL-c and triacylglycerols (TG). Therefore, GSTT1 and GSTP1 variants could be emerging biomarkers to discriminate between BC cases related or not to cardiometabolic disease factors.

Detoxification Role of Metabolic Glutathione S-Transferase (GST) Genes in Blood Lead Concentrations of Jamaican Children with and without Autism Spectrum Disorder.

Glutathione S-transferases (GST) are involved in the detoxification of exogenous chemicals including lead (Pb). Using data from 344 pairs of autism spectrum disorder (ASD) cases and age- and sex-matched typically developing (TD) controls (2–8 years old) from Jamaica, we investigated the interaction between three GST genes and ASD status as determinants of blood Pb concentrations (BPbCs). We found that ASD cases had lower geometric mean BPbCs than TD children (1.74 vs. 2.27 µg/dL, p < 0.01). Using a co-dominant genetic model, ASD cases with the Ile/Val genotype for the GSTP1 Ile105Val polymorphism had lower GM BPbCs than TD controls, after adjusting for a known interaction between GSTP1 and GSTT1, child’s parish, socioeconomic status, consumption of lettuce, fried plantains, and canned fish (Ile/Val: 1.78 vs. 2.13 µg/dL, p = 0.03). Similarly, among carriers of the I/I or I/D (I*) genotype for GSTT1 and GSTM1, ASD cases had lower adjusted GM BPbCs than TD controls (GSTT1 I*: 1.61 vs. 1.91 µg/dL, p = 0.01; GSTM1 I*: 1.71 vs. 2.04 µg/dL, p = 0.01). Our findings suggest that genetic polymorphisms in GST genes may influence detoxification of Pb by the enzymes they encode in Jamaican children with and without ASD.

GSTP1 Ile105Val and GPX1 Pro198Leu Polymorphisms and Their Association with Response to Radiotherapy in Nasopharyngeal Carcinoma Patients

Objectives: Radio-resistance poses a major challenge in nasopharyngeal carcinoma (NPC) treatment. Due to individual variations in radio-sensitivity, biomarkers are needed to tailor radiation treatment. Within this frame, the identification of series of genetic signatures mainly SNPs for NPC patients treated with radiotherapy may help to predict treatment outcome and deliver personalized therapy. The aim of this study was to evaluate the possible association between the GSTP1 Ile105Val and GPX1 Pro198Leu polymorphisms and response to radiotherapy in NPC patients. Methods: From September 2016 to October 2018, a total of 101 patients with confirmed NPC, recruited at Mohammed IV Center for Treatment of Cancer of Casablanca, underwent radiotherapy. DNA was extracted from peripheral blood. Genotyping of the GPX1 Pro198Leu and GPX1 Val105Leu polymorphisms was carried out by PCR amplification and DNA sequencing. SPSS was used to analyse the association of GSTP1 and GPX1 genotypes with clinico-pathological features and response to radiotherapy. Results: The genotyping data revealed the presence of only two genotypes namely Pro/Pro (57.4%) and Pro/Leu (40.6%) for GPX1 gene. The allelic frequencies of C and T alleles were 78.7% and 21.3% respectively. For GSTP gene, the homozygous genotypes Val/Val and Leu/Leu were detected in 35.6% and 12.9% of patients respectively. The heterozygous genotype Val/Leu prevailed (51.5%). Allelic frequencies showed the presence of the two alleles A and G in 57.1% and 42.9% patients respectively. Statistical analysis failed to find any significant association between GSTP Val105Ile and GPX1 Pro198Leu genetic polymorphisms and socio-demographic and clinico-pathological features as well as response to radiotherapy (p>0.05). Conclusion: Further research is warranted on the potential role of SNPs within antioxidant defines genes in radiotherapy response and to identify reliable predictive and non-invasive biomarkers for radio-resistance among NPC patients for personalised therapies. Keywords: Nasopharygeal carcinoma, genetic polymorphisms, GSTP1, GPX1, radio-resistance, prognosis

GSTP1 Ile105Val polymorphism among North Indian lung cancer patients treated using monotherapy and poly-pharmacy.

Genetic polymorphism within the P1 isoenzyme of the Glutathione-S-Transferase (GST) family is found to modulate and alter the enzyme activity of GSTP1 protein and thus may result in a change of sensitivity to platinum-based chemotherapy. We investigated the relationship between GSTP1 Ile105Val polymorphisms and overall survival, treatment response, and for both hematological and non-hematological toxicity of advanced North Indian lung cancer patients undergoing platinum-based double chemotherapy. The polymorphism of GSTP1 Ile105Val in North Indian lung cancer patients was assessed by polymerase chain reaction-restriction fragment length polymorphism. A total of 682 lung cancer patients were enrolled in the study, and it was observed that patients who were carrying both the mutant alleles (Val/Val) for the GSTP1 polymorphism showed a higher trend of median survival time (MST) as compared to the patients bearing the wild type of genotype (Ile/Ile) (MST = 8.30 vs. 7.47, p = 0.56). Based on toxicity profiling, we observed that lung cancer patients with the mutant genotype of GSTP1 (Val/Val) had an increased risk of leukopenia (OR = 2.41; 95% CI = 1.39-4.18, p = 0.001) as compared to subjects carrying both copies of the wild alleles (Ile/Ile). Our data suggested that patients with heterozygous genotype (Ile/Val) had a 2.14-fold increased risk of developing severe anemia (OR = 2.14, 95% CI = 0.97-4.62, p = 0.03). Our data also showed that in small cell lung carcinoma (SCLC) patients' polymorphism of GSTP1 was associated with thrombocytopenia (χ2 test = 7.32, p = 0.02). Our results suggest that GSTP1 Ile105Val polymorphism could be a predictive biomarker for hematological toxicity, like leukopenia and anemia, but not thrombocytopenia or neutropenia.

Association of GSTP1 Ile105Val polymorphism with the risk of coronary heart disease: An updated meta-analysis.

BackgroundNumerous case-control studies have investigated the association between GSTP1 Ile105Val polymorphism and CHD risk, but the results from published studies were inconclusive. The present meta-analysis was performed to derive a more precise estimation.MethodsPubMed, EMBASE, and Web of Science database searches were conducted to retrieve relevant articles.ResultsUltimately, 5,451 CHD cases and 5,561 controls from 15 studies were included. Pooled analysis did not yield any statistically significant association between GSTP1 Ile105Val polymorphism and CHD risk for the overall population (Val vs. Ile: OR, 1.05; 95% CI, 0.93 to 1.18; Val/Val vs. Ile/Ile: OR, 1.09; 95% CI, 0.83 to 1.42; Val/Ile vs. Ile/Ile: OR, 1.09; 95% CI, 0.93 to 1.28; Val/Val vs. Val/Ile+Ile/Ile: OR, 1.04; 95% CI, 0.83 to 1.30; Val/Val+Val/Ile vs. Ile/Ile: OR, 1.14; 95% CI, 0.97 to 1.33). Subgroup analyses and sensitivity analyses indicated that GSTP1 Ile105Val polymorphism was still not associated with an increased risk of CHD. After excluding studies detected by Galbraith plots as major sources of heterogeneity, these relationships were still not significant.ConclusionsThe overall results did not reveal a major role of the GSTP1 Ile105Val polymorphism in modulating CHD risk. Well-designed studies with large sample sizes are needed to validate our findings and explore the possible gene-gene or gene-environment interactions.

Effects of GSTP1 Ile105Val polymorphism on both susceptibility and treatment response of chronic myeloid leukemia

Chronic myeloid leukemia (CML) is a multifactorial disease, which is caused by a complicated interaction between genetic and environmental agents. The Gluthation- S-transferase (GST) covers a family of multifunctional enzymes that involved in the detoxification of various toxic substances and anticancer drugs. Some polymorphisms in GSTs gene, could influence cancer susceptibility and drug resistance. The aim of the present study was to explore the influence of GSTP1 105 Ile/Val (rs1695) gene polymorphism on both CML susceptibility and response to Imatinib.DNA was extracted from blood samples by salting-out method; the Ile105Val polymorphism was genotyped in all participants (200 controls and 112 patients with chronic myeloid leukemia) by using PCR-RFLP method.The results of the present study revealed the absence of a significant association between GSTP1 105 Ile/Val gene polymorphism and CML risk, the variant allele Val was more frequent among controls (32%) than among patients (30)%). However, Hematologic response loss, cytogenetic resistance, side effects related to imatinib and none cytogenetic responders were more frequent among patients harboring val/val genotype compared with patients carrying Ile/ Ile and Ile/val genotypes.We have shown that this polymorphism is not associated with the risk of CML, but it influences the response of our patients treated by imatinib.

The correlation of combined OGG1, CYP1A1 and GSTP1 gene variants and risk of lung cancer of male Iraqi waterpipe tobacco smokers.

Genetic polymorphisms of genes whose products are responsible for activities, such as xenobiotic metabolism, mutagen detoxification and DNA-repair, have been predicted to be associated with the risk of developing lung cancer (LC). The association of LC with tobacco smoking has been extensively investigated, but no studies have focused on the Arab ethnicity. Previously, we examined the association between genetic polymorphisms among Phase I and Phase II metabolism genes and the risk of LC. Here, we extend the data by examining the correlation of OGG1 Ser326Cys combined with CYP1A1 (Ile462Val and MspI) and GSTP1 (Ile105Val and Ala103Val) polymorphisms with the risk of LC. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and gene sequencing were carried out for genotyping the OGG1 polymorphisms of 123 LC patients and 129 controls. No significant differences in the frequencies of the OGG1 mutant allele between patients and controls were found. The distributions of heterozygous Ser/Cys or Cys/Cys genotypes of OGG1 were not associated with the risk of LC either according to the histological types of LC or based on waterpipe tobacco (WP) smoking status. In contrast, the combined effect of OGG1 variants with CYP1A1 and GSTP1 variants revealed a significant correlation with the OGG1 Ser326Cys-CYP1A1 MspI variants pairing. This association was significant (p = 0.001) in individuals who carried homozygous or heterozygous variant type genotypes of both genes in a reference with carriers of both wild-type genotypes (wt/wt - wt/wt). The odds ratios were 2.99 (95% CI 1.67-5.36), 2.68 (95% CI 1.08-6.62), and 2.80 (95% CI 1.18-6.69) for those who carried (wt/wt - wt/vt + vt/vt), (wt/vt + vt/vt - wt/wt), and (wt/vt + vt/vt - wt/vt + vt/vt), respectively. The study suggests a limited correlation is present between carrying OGG1 Ser326Cys polymorphism and the risk of developing LC in Arab populations.

Hypermethylation in Gene Promoters Are Induced by Chronic Exposure to Benzene, Toluene, Ethylbenzene and Xylenes.

Gas station attendants are occupationally exposed to benzene, toluene, ethylbenzene and xylene (BTEX) compounds and thus more susceptible to the biological effects of this mixture present in gasoline, especially due to the carcinogenicity of benzene. Furthermore, the harmful effects of BTEX exposure may be potentiated by genetic and epigenetic inactivation of critical genes. The objective was to evaluate such gene-BTEX interactions accessing the promoter methylation status of p14ARF, p16INK4A and GSTP1 in peripheral blood leukocyte samples. The 59 exposed and 68 unexposed participants from Rio de Janeiro, Brazil, were included. The promoter methylation status was accessed by methylation-specific PCR (MSP) and GSTP1 Ile105Val polymorphism was investigated by PCR-restriction fragment length polymorphism (PCR-RFLP) technique. Both p14ARF and p16INK4A were significantly hypermethylated in exposed subjects compared to unexposed (p = 0.004 and p<0.001, respectively). Additionally, p16INK4A hypermethylation in the exposed group was correlated with chromosomal abnormalities (CAs) (p = 0.018), thus highlighting the influence of the gene-environment interactions on genome instability. Noteworthy, p16INK4A methylation was significantly associated with miscarriage among female attendants (p = 0.047), in which those who reported miscarriage exhibited hypermethylation in at least 2 of the 3 genes analyzed. The GSTP1 heterozygote genotype, which could affect the metabolism of benzene detoxification, was found in both groups but was more frequent in those occupationally exposed. No significant association was observed between GSTP1 genotypes and methylation status. Together, these findings indicate that gas station attendants with the aforementioned epigenetic and genetic profiles may be at greater risk of occupational BTEX exposure-induced genome instability, which could require concerted efforts to establish more preventive actions and constant biomonitoring in gas station attendants.

Association Between Glutathione-S-Transferase Gene Polymorphisms and Responses to Tyrosine Kinase Inhibitor Treatment in Patients with Chronic Myeloid Leukemia: A Meta-analysis.

Although many earlier studies revealed an effect of glutathione-S-transferase (GST) gene polymorphisms on tyrosine kinase inhibitor (TKI) treatment responses in chronic myeloid leukemia (CML) patients, the significance of this relationship remains controversial. This study aimed to review and meta-analyze treatment responses to TKIs in patients with CML and GST gene polymorphisms, including GSTT1, GSTM1, and GSTP1. We searched four medical databases, PubMed, Web of Science, the Cochrane Library, and Embase, by using keywords related to GST gene polymorphisms and clinical responses in CML patients receiving TKI treatment. The meta-analysis was performed using RevMan version 5.3 and Comprehensive Meta-Analysis software version 3.0. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to examine the association between GSTT1, GSTM1, and GSTP1 polymorphisms and TKI treatment responses in patients with CML. The null polymorphisms of GSTT1 and GSTM1 did not affect TKI treatment responses, while the GSTP1 Ile105Val polymorphism had a significant impact on responses to TKI. Patients who were GSTP1 variant allele carriers (AG + GG) had poor responses to TKI treatment compared to patients who were wild-type homozygote carriers (AA) (OR 1.85, 95% CI 1.31-2.62; p < 0.001). This meta-analysis of patients with CML showed that G allele carriers with GSTP1 Ile105Val polymorphism had significantly worse responses to TKI treatment than wild-type homozygote carriers.

98P - Influence of DPYD*9, DPYD*6 and GSTP1 ile105val genetic polymorphisms on capecitabine and oxaliplatin (CAPOX) associated toxicities in colorectal cancer patients

BackgroundCapecitabine and oxaliplatin combination regimen (CAPOX) is the standard chemotherapeutic care for the treatment of colorectal cancer (CRC). CAPOX treatment is found to be equivalent to FOLFOX and FOLFRI in efficacy and preferred over them due to its easy management and convenience in administration. However, CAPOX treatment was associated with several dose-limiting toxicities and high inter-individual variation in toxicity profile. These toxicities may limit treatment effectiveness as they impose treatment interruption or even discontinuation. Therefore, there is a critical need for identifying the predictive biomarkers for CAPOX related toxicities. MethodsPatients and methods: In an intent treat analysis, 145 CRC patients were recruited. Patients received a standard treatment schedule of oxaliplatin 130 mg/m2 infusion over 2 hours on day 1 and oral capecitabine 1000mg/m2 in divided doses twice daily for the next 14 days of a 21-day cycle. 5 ml of the venous blood was collected from each patient and genomic DNA was extracted by the phenol-chloroform method. The genotyping analysis of the selected SNP’s was carried out by real-time PCR using TaqMan SNP genotyping assays from applied biosystems. ResultsThe major dose-limiting toxicities observed with CAPOX treatment were thrombocytopenia, HFS and PN. DPYD*9 carries were found to be at higher risk for HFS, diarrhoea and thrombocytopenia when compared to patients with wild allele. No significant association was found between DPYD*6, GSTP1 ile105val polymorphisms and CAPOX related toxicities except for thrombocytopenia. ConclusionsA significant association was observed between DPYD*9A A>G polymorphism and CAPOX induced dose-limiting toxicities like HFS, diarrhoea and thrombocytopenia strengthening its role as a predictive biomarker. Legal entity responsible for the studyAshok Varma. FundingJawaharlal Institute of Post-Graduate Medical Education and Research (JIPMER). DisclosureThe author has declared no conflicts of interest.

Influence of DPYD*9A, DPYD*6 and GSTP1 ile105val Genetic Polymorphisms on Capecitabine and Oxaliplatin (CAPOX) Associated Toxicities in Colorectal Cancer (CRC) Patients

Aim:CAPOX treatment in CRC patients was reported to cause several dose-limiting toxicities, and are found responsible for treatment interruption or even discontinuation. Therefore there is a critical need for identifying the predictive biomarkers for such toxicities to prevent them. The aim of our present study is to find the influence of DPYD*9A, DPYD*6 and GSTP1 ile105val gene polymorphisms on CAPOX treatment-associated toxicities in south Indian patients with CRC. Patients and Methods:We have recruited 145 newly diagnosed and treatment naive CRC patients in the study. Each Patient received a standard treatment schedule of oxaliplatin 130 mg/m2 infusion over 2 hours on day 1 and oral capecitabine 1000mg/m2 in divided doses twice daily for the next 14 days of a 21-day cycle. 5 ml of the venous blood was collected from each patient and genomic DNA extraction and genotyping. The genotyping analysis of the selected genetic polymorphisms was carried out by real-time PCR using TaqMan SNP genotyping assays obtained from applied biosystems. Results:The major dose-limiting toxicities observed with CAPOX treatment were thrombocytopenia, HFS and PN. DPYD*9A carries were found to be at higher risk for HFS, diarrhoea and thrombocytopenia when compared to patients with wild allele. No significant association was found between DPYD*6, GSTP1 ile105val polymorphisms and CAPOX related toxicities except for thrombocytopenia. Conclusion:A significant association was observed between DPYD*9A polymorphism and CAPOX induced dose-limiting toxicities strengthening its role as a predictive biomarker.

GSTM1, GSTT1 and GSTP1 Ile105Val polymorphisms in outcomes of head and neck squamous cell carcinoma patients treated with cisplatin chemoradiation

Cisplatin (CDDP) combined with radiotherapy (RT) is employed in head and neck squamous cell carcinoma (HNSCC) with variable toxicities and clinical response. Glutathione S-transferases (GSTs) participate in CDDP excretion from cells, and genes encoding GSTs, GSTM1, GSTT1and GSTP1, are polymorphic in humans. This prospective study aimed to evaluate the roles of GSTM1, GSTT1, and GSTP1 Ile105Val polymorphisms in outcomes of HNSCC patients treated with CDDP chemoradiation. Ninety patients were genotyped by multiplex PCR. Urinary CDDP measurements were performed by HPLC. Treatment side effects and response were analysed by conventional criteria. Patients with GSTT1 genes showed 7.23- and 5.37-fold higher likelihood of presenting vomiting and ototoxicity, lower glomerular filtration rate (GFR), and lower elimination of CDDP in urine relative to patients with deleted genes. Patients harbouring the GSTP1 IleVal or ValVal genotypes showed 4.28-fold higher likelihood of presenting grade 2 or 3 vomiting and lower GFR with treatment than those harbouring the IleIle genotype. In multivariate Cox analysis, patients with the GSTP1 105ValVal genotype had 3.87 more chance of presenting disease progression than those with the IleIle or IleVal genotype (p < 0.01). Our findings provide preliminary evidence that inherited abnormalities in CDDP metabolism, related to GSTT1 and GSTP1 Ile105Val polymorphisms, alter outcomes of HNSCC patients treated with CDDP and RT.

Influence of glutathione S-transferases (GSTM1, GSTT1, and GSTP1) genetic polymorphisms and smoking on susceptibility risk of chronic myeloid leukemia and treatment response.

BackgroundGlutathione S‐transferases (GSTs) polymorphisms may impact on chronic myeloid leukemia (CML) risk or heterogeneous responses to Imatinib mesylate (IM). The aim of this study was to evaluate the correlation between GSTs polymorphisms and CML risk, treatment response.MethodsWe genotyped GSTM1, GSTT1 null deletion polymorphisms, and GSTP1 Ile105Val polymorphism by PCR methods and BCR‐ABL transcripts were analyzed by qRT‐PCR in 104 CML patients and 104 sex‐ and age‐matched healthy individuals.ResultsIndividual analysis showed significant association of GSTM1 (p = 0.008; OR = 0.46; 95% CI: 0.26–0.82) and GSTP1 genes (p = 0.04; OR = 1.56; 95% CI: 1.016–2.423) with CML risk. The combined analysis indicated that GSTM1 null/GSTT1 present, GSTM1‐null/GSTP1M*(AG/GG) as well as GSTT1 present/ GSTP1M* genotype were associated with CML risk (ORg(‐):2.28; 95% CI: 1.29–4.04; ORgg: 2.85; 95% CI: 1.36–5.97; OR(‐)g: 1.75; 95% CI: 0.99–3.06, respectively). The proportion of CML cancer attributable to the interaction of smoking and GSTM1 null, GSTT1null, and GSTP1 M* was 42%, 39%, and 13%, respectively. Patients with GSTM1‐null and GSTP1 AG/GG genotype had significantly a lower rate of MMR achievement (p = 0.00; p = 0.009 respectively). Event‐free survival (EFS) percentage was similar between GSTM1 null and GSTM1 present patients (p = 0.21).ConclusionOur study suggests the influence of GSTM1 and GSTP1 polymorphisms on CML risk and treatment response. The interaction between GSTs polymorphisms and smoking plays a significant role on CML susceptibility.

Glutathione S-transferase gene polymorphisms and risk of nasal or colorectal polyposis.

We observed inconsistent conclusions regarding the genetic role of glutathione S-transferase gene polymorphisms, including glutathione S-transferase M1 (GSTM1), glutathione S-transferase T1 (GSTT1) present/null, and glutathione S-transferase pi (GSTP1) Ile105Val polymorphisms, in the susceptibility to nasal or colorectal polyposis (NP or CP). Thus, we aimed to perform a meta-analysis to comprehensively evaluate this association by applying Stata/SE software. After the heterogeneity assumption, Mantel–Haenszel statistics were used to obtain the odds ratio (OR), 95% confidence interval (95% CI) and P-value of the association test (PA). We obtained a total of 235 articles by searching online databases. After screening, ten eligible case–control studies were finally enrolled in our meta-analysis. For the meta-analysis of the GSTT1 gene under present versus null, we observed a decreased risk of NP [OR = 0.65; PA=0.018], but not CP. In addition, we did not detect any evident association between the GSTM1 present/null polymorphism and NP or CP risk. For the meta-analysis of the GSTP1 Ile105Val polymorphism, compared with controls, an increased risk of NP cases was detected under the models of Val versus Ile (OR = 1.36; PA=0.027), Ile/Val versus Ile/Ile (OR = 1.70; PA=0.011) and Ile/Val+Val/Val versus Ile/Ile (OR = 1.65; PA=0.010). In conclusion, the null genotype of the GSTT1 polymorphism may be linked to an increased susceptibility to NP, whereas the Ile/Val genotype of the GSTP1 Ile105Val polymorphism may be associated with a decreased risk of NP.

Molecular evaluation of glutathione S transferase family genes in patients with sporadic colorectal cancer.

AIMTo evaluate the association between polymorphisms in glutathione S transferases (GSTs) and the risk of sporadic colorectal cancer (SCRC), tumor progression and the survival of patients.METHODSA case-control study of 970 individuals from the Brazilian population was conducted (232 individuals from the case group with colorectal cancer and 738 individuals from the control group without a history of cancer). PCR multiplex and PCR-RFLP techniques were used to genotype the GST polymorphisms. The tumors were categorized according to the TNM classification: tumor extension (T), affected lymph nodes (N), and presence of metastasis (M). Logistic regression, multiple logistic regression and survival analysis were used to analyze the data. The results are presented in terms of odds ratio (OR) and 95% confidence interval (CI). The level of significance was set at 5% (P ≤ 0.05).RESULTSAge equal to or over 62 years (OR = 8.79; 95%CI: 5.90-13.09, P < 0.01) and female gender (OR = 2.91; 95%CI: 1.74-4.37; P < 0.01) were associated with increased risk of SCRC. Analysis of the polymorphisms revealed an association between the GSTM1 polymorphisms and a risk of SCRC (OR = 1.45; 95%CI: 1.06-2.00; P = 0.02), as well as between GSTT1 and a reduced risk of the disease (OR = 0.65; 95%CI: 0.43-0.98; P = 0.04). An interaction between the presence of the wild-type allele of GSTP1 Ile105Val polymorphism and tobacco consumption on risk of SCRC (OR = 2.33; 95%CI: 1.34-4.05; P = 0.05) was observed. There was an association between the GSTM1 null genotype and the presence of advanced tumors (OR = 2.33; 95%CI: 1.23-4.41; P = 0.009), as well as increased risk of SCRC in the presence of a combination of GSTT1 non-null/GSTM1 null genotypes (OR = 1.50; 95%CI: 1.03-2.19; P = 0.03) and GSTT1 non-null/GSTM1 null/GSTP1 Val* (OR = 1.85; 95%CI: 1.01-3.36, P = 0.04). Combined GSTT1 non-null/GSTM1 null genotypes (OR = 2.40; 95%CI: 1.19-4.85; P = 0.01) and GSTT1 non-null/GSTM1 null/GSTP1 Val* (OR = 2.92; 95%CI: 1.05-8.12; P = 0.04) were associated with tumor progression. Polymorphisms were not associated with the survival of patients with SCRC.CONCLUSIONFemales aged 62 years or older are more susceptible to SCRC. Polymorphisms of GSTT1 and GSTM1 null genotypes modulated the susceptibility to SCRC in the population studied.

Investigation of Gluthatione S-Transferase Variants in a Healthy Population in Goiânia-Go

Genetic polymorphisms in glutathione S-transferases (GSTs) genes might influence the detoxification activities of the enzymes predisposing individuals to a lot of disiases. Owing to the presence of these genetic variants, inter-individual and ethnic differences in GSTs detoxification capacity have been observed in various populations. Therefore, the present study was performed to determine the prevalence GSTM1*0/*0, GSTT1*0/*0 and GSTP1 Ile105Val polymorphisms in 100 healthy individuals from Goiânia - GO. GSTM1 and GSTT1 polymorphisms were analyzed by a Multiplex-PCR approach, whereas GSTP1 polymorphisms were examined by PCR-RFLP. The frequencies of GSTM1 and GSTT1 *0/*0 genotypes are 49% and 31%, respectively. The frequencies of GSTP1 Ile/Ile, Ile/Val and Val/Val genotypes were 40%, 53% and 7%, respectively. The wild-type (Ile) and variant (Val) allele frequencies were 66.5% and 33.5%, respectively. The combined genotypes distribution of GSTM1, GSTT1 and GSTP1 polymorphisms showed 12 possible genotypes present in our population; seven of them have a frequency greater than 5%. The effect of combined genotypes of these GSTs polymorphisms is still unknown. These findings in healthy population, give us such more information for the future epidemiological and clinical studies. Using to examine the effect of these combinations in drugs metabolism and cancer predisposition, further largest group would be needed, since their frequencies are quite low. To our of GSTs polymorphisms, this is the first study indicating the frequencies of genetic polymorphisms of GST superfamily in a health population in a Goiania population.

GSTP1 Ile105Val polymorphism might be associated with the risk of radiation pneumonitis among lung cancer patients in Chinese population: A prospective study.

Background: Growing data suggest that DNA damage repair and detoxification pathways play crucial roles in radiation-induced toxicities. To determine whether common functional single-nucleotide polymorphisms (SNPs) in candidate genes from these pathways can be used as predictors of radiation pneumonitis (RP), we conducted a prospective study to evaluate the associations between functional SNPs and risk of RP.Methods: We recruited a total of 149 lung cancer patients who had received intensity modulated radiation therapy (IMRT). GSTP1 and XRCC1 were genotyped using the SurPlexTM-xTAG method in all patients. RP events were prospectively scored using the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE), version 4.0. Kaplan-Meier analysis was used to determine the cumulative probability of RP of grade ≥ 2. Cox proportional hazard regression was performed to identify clinical variables and SNPs associated with risk of RP grade ≥ 2, using univariate and multivariate analysis, respectively.Results: With a median follow-up of 9 months, the incidence of RP of grade ≥ 2 was 38.3%. A predicting role in RP was observed for the GSTP1 SNP (adjusted hazard ratio 3.543; 95% CI 1.770-7.092; adjusted P< 0.001 for the Ile/Val and Val/Val genotypes versus Ile/Ile genotype). Whereas, we found that patients with XRCC1 399Arg/Gln and Gln/Gln genotypes had a lower risk of RP compares with those carrying Arg/Arg genotype (adjusted HR 0.653; 95% CI 0.342-1.245), but with no statistical significance observed (adjusted P = 0.195).Conclusions: Our results suggested a novel association between GSTP1 SNP 105Ile/Val and risk of RP development, which suggests the potential use of this genetic polymorphism as a predictor of RP. In addition, genetic polymorphisms of XRCC1 399Arg/Gln may also be associated with RP.