GSTM1 and GSTT1 polymorphisms contribute to renal cell carcinoma risk: evidence from an updated meta-analysis

Role of GSTM1 in Hypertension, CKD, and Related Diseases across the Life Span

Over 20 years after the introduction of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers, CKD remains a major public health burden with limited therapeutic options to halt or slow kidney disease progression at all ages. The consensus is that oxidative stress contributes to CKD development and progression. Yet, to date, there is no clear evidence that broad use of antioxidant therapy provides a beneficial effect in CKD. Understanding the specific pathophysiologic mechanisms in those who are genetically most susceptible to oxidative stress is a crucial step to inform therapy in an individualized medicine approach, considering differing exposures and risks across the life span. Glutathione-S-transferase μ 1 (GSTM1) is a phase 2 enzyme involved in inactivation of reactive oxygen species and metabolism of xenobiotics. In particular, those with the highly prevalent GSTM1 null genotype (GSTM1[0/0]) may be more susceptible to kidney disease progression, due to impaired capacity to handle the increased oxidative stress burden in disease states, and might specifically benefit from therapy that targets the redox imbalance mediated by loss of the GSTM1 enzyme. In this review, we will discuss the studies implicating the role of GSTM1 deficiency in kidney and related diseases from experimental rodent models to humans, from the prenatal period through senescence, and the potential underlying mechanism.

Cancer risk and nullity of Glutathione-S-transferase mu and theta 1 in occupational pesticide workers

Occupational exposure to pesticides has been associated with adverse health conditions, including genotoxicity and cancer. Nullity of GSTT1/GSTM1 increases the susceptibility of pesticide workers to these adverse health effects due to lack of efficient detoxification process created by the absence of these key xenobiotic metabolizing enzymes. However, this assertion does not seem to maintain its stance at all the time; some pesticide workers with the null genotypes do not present the susceptibility. This suggests the modulatory role of other confounding factors, genetic and environmental conditions. Pesticides, aggravated by the null GSTT1/GSTM1, cause genotoxicity and cancer through oxidative stress and miRNA dysregulation. Thus, the absence of these adverse health effects together with the presence of null GSTT1/GSTM1 genotypes demands further explanation. Also, understanding the mechanism behind the protection of cells - that are devoid of GSTT1/GSTM1 - from oxidative stress constitutes a great challenge and potential research area. Therefore, this review article highlights the recent advancements in the presence and absence of cancer risk in occupational pesticide workers with GSTT1 and GSTM1 null genotypes.

Prognostic and predictive value of a mRNA signature in peripheral T-cell lymphomas: A mRNA expression analysis

Current international prognostic index is widely questioned on the risk stratification of peripheral T‐cell lymphoma and does not accurately predict the outcome for patients. We postulated that multiple mRNAs could combine into a model to improve risk stratification and helping clinicians make treatment decisions. In this study, the gene expression profiles were downloaded from the Gene Expression Omnibus (GEO) database. Weighted gene co‐expression network analysis (WGCNA) was used to screening genes in selected module which most closely related to PTCLs, and then built a mRNA signature using a LASSO Cox regression model and validated the prognostic accuracy of it. Finally, a nomogram was constructed and the performance was assessed. A total of 799 WGCNA‐selected mRNAs in black module were identified, and a mRNA signature which based on DOCK2, GSTM1, H2AFY, KCNAB2, LAPTM5 and SYK for PTCLs was developed. Significantly statistical difference can be seen in overall survival of PTCLs between low‐risk group and high‐risk group (training set:hazard ratio [HR] 4.3, 95% CI 2.4‐7.4, P < .0001; internal testing set:hazard ratio [HR] 2.4, 95% CI 1.2‐4.8, P < .01; external testing set:hazard ratio [HR] 2.3, 95% CI 1.10‐4.7, P = .02). Furthermore, multivariate regression demonstrated that the signature was an independently prognostic factor. Moreover, the nomogram which combined the mRNA signature and multiple clinical factors suggesting that predicted survival probability agreed well with the actual survival probability. The signature is a reliable prognostic tool for patients with PTCLs, and it has the potential for clinicians to implement personalized therapeutic regimen for patients with PTCLs.

Association of CYP1A1, GSTM1 and GSTT1 gene polymorphisms with risk of prostate cancer in Algerian population

Background

Prostate cancer is the most common cancer in the world, and its etiology involves the interaction of genetic and environmental factors. Interindividual differences observed in the metabolism of xenobiotics may be due to polymorphisms of genes encoding the detoxification enzymes. This genetic variability seems to be associated with differences in susceptibility to certain types of cancers, including prostate cancer. Our study has been made in order to investigate a possible genetic predisposition to prostate cancer in an Algerian population, through the analysis of genetic polymorphisms of three enzymes metabolizing xenobiotics namely cytochrome P450 (CYP) 1A1, glutathione S-transferase mu 1 (GSTM1) and GST theta 1 (GSTT1).

Methods

The current case–control study included 101 prostate cancer patients and 101 healthy controls. Genotyping of CYP1A1 T3801C polymorphisms and GSTM1/GSTT-null was made, respectively, by PCR-RFLP and multiplex PCR.

Results

No significantly positive associations were found for the CYP1A1 T3801C [p = 0.71, OR = 1.23 (0.56–2.72)] and GSTM1-null [p = 0.26, OR = 1.37 (0.76–2.4)] polymorphisms and prostate cancer susceptibility. However, we detect a highly significant association between GSTT1-null genotype [p = 0.03, OR = 2.03 (1.06–3.99)], GSTM1/GSTT1-double null genotype [p = 0.027, OR = 2.6; CI (1.07–6.5)] and prostate cancer risk. Furthermore, no statistically significant differences between the studied polymorphisms and tumor parameters (the Gleason score and clinical stages of aggressiveness) at diagnosis of PCa.

Conclusions

The risk of developing prostate cancer in Algeria does not appear to be associated with CYP1A1 T3801C genotypes and GSTM1-null, but GSTT1-null and GSTM1/GSTT1-double null genotypes increased the risk of prostate cancer.

Glutathione transferase genotypes may serve as determinants of risk and prognosis in renal cell carcinoma

Renal cell carcinoma (RCC) represents a group of histologically similar neoplasms with significant intratumor and intertumor genetic heterogeneity. Recognized risk factors for RCC development include smoking, hypertension, obesity, as well as von Hippel-Lindau (VHL) disease. Inactivation of VHL, deregulated nuclear factor (erythroid-derived 2)-like 2 (Nrf2) pathway, and altered redox homeostasis, together with changes in glutathione transferase (GST) profile, are considered as important contributing factors in RCC development and progression. Although the available results of both gene-gene and gene-environment analysis are quite heterogeneous, they clearly indicate that certain GST genotypes may play a role as risk modifiers, either individually or in combination with other Phase I or Phase II gene polymorphisms, as well as in subjects exposed to relevant substrates. Seemingly, GST genotyping could identify individuals with impaired detoxification in renal parenchyma that are at higher risk of developing RCC. In addition to well established roles of GSTs in conjugation and biotransformation of xenobiotics, GSTs have emerged as significant regulators of pathways determining cell proliferation and survival. Indeed, there are evidence in favor of GST significance, not only in terms of risk for RCC development, but also with respect to progression and prognosis. So far, GSTM1-active genotype was confirmed to be an independent predictor of higher risk of overall mortality. Therefore, it is reasonable to assume that certain GST variants may assist in individual RCC risk assessment, as well as postoperative prognosis. Even more, GST profiling might contribute to development of personalized targeted therapy in RCC patients.

GSTO1*CC Genotype (rs4925) Predicts Shorter Survival in Clear Cell Renal Cell Carcinoma Male Patients

Omega class glutathione transferases, GSTO1-1 and GSTO2-2, exhibit different activities involved in regulation of inflammation, apoptosis and redox homeostasis. We investigated the the prognostic significance of GSTO1 (rs4925) and GSTO2 (rs156697 and rs2297235) polymorphisms in clear cell renal cell carcinoma (ccRCC) patients. GSTO1-1 and GSTO2-2 expression and phosphorylation status of phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt)/ /mammalian target of rapamycin (mTOR) and Raf/MEK/extracellular signal-regulated kinase (ERK) signaling pathways in non-tumor and tumor ccRCC tissue, as well as possible association of GSTO1-1 with signaling molecules were also assessed. GSTO genotyping was performed by quantitative PCR in 228 ccRCC patients, while expression and immunoprecipitation were analyzed by Western blot in 30 tissue specimens. Shorter survival in male carriers of GSTO1*C/C wild-type genotype compared to the carriers of at least one variant allele was demonstrated (p = 0.049). GSTO1*C/C genotype independently predicted higher risk of overall mortality among male ccRCC patients (p = 0.037). Increased expression of GSTO1-1 and GSTO2-2 was demonstrated in tumor compared to corresponding non-tumor tissue (p = 0.002, p = 0.007, respectively), while GSTO1 expression was correlated with interleukin-1β (IL-1β)/pro-interleukin-1β (pro-IL-1β) ratio (r = 0.260, p = 0.350). Interaction of GSTO1 with downstream effectors of investigated pathways was shown in ccRCC tumor tissue. This study demonstrated significant prognostic role of GSTO1 polymorphism in ccRCC. Up-regulated GSTO1-1 and GSTO2-2 in tumor tissue might contribute to aberrant ccRCC redox homeostasis.

A systematic review and meta-analyses of the relationship between glutathione S-transferase gene polymorphisms and renal cell carcinoma susceptibility

BACKGROUND

Association of GSTM1- and GSTT1-null genotypes, GSTP1 A/G gene polymorphism with renal cell carcinoma (RCC) susceptibility was detected, and the relationship between the GSTM1/GSTT1-null genotype and clinical TNM stages of RCC was assessed, using meta-analysis method.

METHODS

Association investigations according to eligibility criteria were searched and identified from the databases of Cochrane Library, PubMed, and Embase from establishment time of databases to July 1, 2017, and eligible reports were analyzed by meta-analysis. 95% confidence intervals (CI) were also detected, and odds ratios (OR) was used to express the results for dichotomous data.

RESULTS

This meta-analysis indicated that there was no an association between GSTM1-null genotype, GSTT1-null genotype, GSTP1 A/G gene polymorphism and RCC risk in the overall population of Caucasians or Asians. The dual GSTM1-GSTT1-null genotype was also not associated with RCC in the overall population of Caucasians. Interestingly, there was an association between the dual GSTM1-GSTT1-null genotype and the susceptibility of RCC in Asians. Relationship of the GSTM1-null genotype with clinical TNM stage of RCC was not observed in the overall population of Asians or Caucasians. In this meta-analysis, no association between the GSTT1-null genotype and clinical TNM stage of RCC was observed in Caucasians or Asians. Interestingly, GSTT1-null genotype was detected to be associated with the clinical TNM stages in patients with RCC in the overall population.

CONCLUSION

The dual GSTM1-GSTT1-null genotype is detected to be associated with the onset of RCC in Asians, and there is an association between the GSTT1-null genotype and the clinical TNM stages in patients with RCC in the overall population.

Bagging Nearest-Neighbor Prediction independence Test: an efficient method for nonlinear dependence of two continuous variables

Testing dependence/correlation of two variables is one of the fundamental tasks in statistics. In this work, we proposed an efficient method for nonlinear dependence of two continuous variables (X and Y). We addressed this research question by using BNNPT (Bagging Nearest-Neighbor Prediction independence Test, software available at https://sourceforge.net/projects/bnnpt/). In the BNNPT framework, we first used the value of X to construct a bagging neighborhood structure. We then obtained the out of bag estimator of Y based on the bagging neighborhood structure. The square error was calculated to measure how well Y is predicted by X. Finally, a permutation test was applied to determine the significance of the observed square error. To evaluate the strength of BNNPT compared to seven other methods, we performed extensive simulations to explore the relationship between various methods and compared the false positive rates and statistical power using both simulated and real datasets (Rugao longevity cohort mitochondrial DNA haplogroups and kidney cancer RNA-seq datasets). We concluded that BNNPT is an efficient computational approach to test nonlinear correlation in real world applications.

Genetic variants and increased risk of meningioma: an updated meta-analysis

PURPOSE

Various genetic variants have been reported to be linked to an increased risk of meningioma. However, no confirmed conclusion has been obtained. The purpose of the study was to investigate potential meningioma-associated gene polymorphisms, based on published evidence.

MATERIALS AND METHODS

An updated meta-analysis was performed in September 2016. After electronic database searching and study screening, we selected eligible case-control studies and extracted data for meta-analysis, using Mantel-Haenszel statistics. P-values, pooled odds ratios (ORs), and 95% confidence intervals were calculated.

RESULTS

We finally selected eight genes with ten polymorphisms: MLLT10 rs12770228, CASP8 rs1045485, XRCC1 rs1799782, rs25487, MTHFR rs1801133, rs1801131, MTRR rs1801394, MTR rs1805087, GSTM1 null/present, and GSTT1 null/present. Results of meta-analyses showed that there was increased meningioma risk in case groups under all models of MLLT10 rs12770228 (all OR >1, P<0.001), compared with control groups. Similar results were observed under the allele, homozygote, dominant, and recessive models of MTRR rs1801394 (all OR >1, P<0.05), and the heterozygote and dominant models of MTHFR rs1801131 in the Caucasian population (all OR >1, P<0.05). However, no significantly increased meningioma risks were observed for CASP8 rs1045485, XRCC1 rs25487, rs1799782, MTHFR rs1801133, MTR rs1805087, or GSTM1/GSTT1 null mutations.

CONCLUSION

Our updated meta-analysis provided statistical evidence for the role of MLLT10 rs12770228, MTRR rs1801394, and MTHFR rs1801131 in increased susceptibility to meningioma.

GSTM1 genotype is an independent prognostic factor in clear cell renal cell carcinoma

PURPOSE

Owing to dual functionality of cytosolic glutathione S-transferases (GSTs), they might affect both the development and the progression of renal cell carcinoma (RCC). However, the data on the prognostic value of GST polymorphism in patients with RCC are scarce. Hence, we evaluated the effect of GST gene variants on both the risk of RCC development and the postoperative prognosis in patients with clear cell RCC (ccRCC).

METHODS

GST genotypes were determined in 305 patients with RCC and 326 matched controls, whereas the overall survival was evaluated in patients with ccRCC only. The presence of GSTM1:ASK1 protein-protein interaction in ccRCC tissue samples was analyzed by methods of immunoprecipitation and immunoblot.

RESULTS

We noted an increased risk of RCC development in carriers of GSTM1-null and GSTP1-variant genotype (P<0.05). On the contrary, survival analysis indicated shorter overall survival for patients with ccRCC with GSTM1-active genotype (P = 0.026). Furthermore, patients with ccRCC with GSTM1-active genotype had significantly higher hazard ratio (P<0.05), in analyzed regression models, compared with the carriers of GSTM1-null genotype. Finally, the presence of GSTM1:ASK1 protein-protein interaction was found in all RCC tissue samples studied.

CONCLUSIONS

Carriers of GSTM1-null and GSTP1-variant genotypes are in increased risk of RCC development. On the contrary, GSTM1-null genotype is associated with favorable postoperative prognosis in ccRCC. The possible molecular mechanism underlying the role of GSTM1 protein in RCC progression might be the presence of GSTM1:ASK1 protein-protein interaction. Hence, determination of GSTM1-genotype might serve as a valuable indicator in both RCC risk assessment and postoperative prognosis.

The relationship between GSTA1, GSTM1, GSTP1, and GSTT1 genetic polymorphisms and bladder cancer susceptibility: A meta-analysis

BACKGROUND

Previous studies have investigated the relationship between GSTA1, GSTM1, GSTP1, and GSTT1 polymorphisms and bladder cancer (BCa) susceptibility, respectively, but the results remain inconsistent. So, we conducted this meta-analysis including 79 case-control studies to explore such relationships.

METHODS

We searched PubMed, EMBASE, Cochrane library, Web of Science, and CNKI for relevant available studies. The pooled odds ratios (ORs) with 95% confidence intervals (CIs) were implemented to evaluate the intensity of associations. Publication bias was estimated using Begg funnel plots and Egger regression test. To assess the stability of the results, we used sensitivity analysis with the method of calculating the results again by omitting 1 single study each time. Between-study heterogeneity was tested using the I statistic.

RESULTS

No significant association between GSTA1 polymorphism and BCa susceptibility (OR = 1.05, 95% CI 0.83-1.33) was noted. Besides, meaningful association between individuals who carried the GSTM1 null genotype and increased BCa risk was detected (OR = 1.39, 95%CI 1.28-1.51). When stratified by ethnicity, significant difference was found in both Caucasian (OR = 1.39, 95% CI 1.23-1.58) and Asian populations (OR = 1.45, 95% CI 1.31-1.61). Moreover, in the subgroup analysis by source of controls (SOC), the results were significant in both hospital-based control groups (OR = 1.49, 95% CI 1.35-1.64) and population-based control groups (OR = 1.21, 95% CI = 1.07-1.37). Additionally, the analysis revealed no significant association between GSTP1 polymorphism and BCa risk (OR = 1.07, 95% CI 0.96-1.20). What is more, significant associations between GSTT1 polymorphism and BCa susceptibility were discovered (OR = 1.11, 95% CI 1.00-1.22). In the subgroup analysis by ethnicity, significant associations between GSTT1 null genotype and BCa risk were observed only in Caucasians (OR = 1.25, 95% CI 1.09-1.44). Furthermore, when stratified by SOC, no obvious relationship was found between the GSTT1 null genotype polymorphism with hospital-based population (OR = 1.11, 95% CI 0.97-1.28) or population-based population (OR = 1.10, 95% CI 0.96-1.27).

CONCLUSION

This study suggested that GSTM1 null genotype and GSTT1 null genotype might be related to higher BCa risk, respectively. However, no associations were observed between GSTA1 or GSTP1 polymorphisms and BCa susceptibility.

A genetic polymorphism affects the risk and prognosis of renal cell carcinoma: association with follistatin-like protein 1 expression

Few single nucleotide polymorphisms (SNPs) associated with the risk of renal cell carcinoma (RCC) have been identified, yet genetic predisposition contributes significantly to this malignancy. We previously showed that follistatin-like 1 (FSTL1) was significantly down-regulated in clear cell RCC (ccRCC), in particular metastatic ccRCC. In the present study, we systemically investigated the associations of the 6 SNPs within FSTL1-coding genomic region with RCC risk and postoperative prognosis. Age- and gender-matched case-control study (417 vs 855) indicated that rs1259293 variant genotype CC was significantly associated with an increased risk of RCC, with an odds ratio of 2.004 (95% confidence internal [CI] = 1.190-3.375). Multivariate Cox regression analysis in 309 of 417 cases showed that rs1259293 genotype (CC vs TT + CT) independently predicted an unfavorable prognosis, with a hazard ratio of 2.531 (95% CI = 1.052-6.086). Expression of FSTL1 was significantly higher in adjacent renal tissues than in tumors, and significantly higher in the tissues with rs1259293 TT genotype than in those with rs1259293 TC+CC genotypes. rs1259293 C allele might generate a CTCF binding site that blocks trans-activation of FSTL1 expression. Our results indicate that rs1259293 is associated with an increased risk and unfavorable postoperative prognosis of RCC, possibly by down-regulating FSTL1 expression in renal tissues.