BACKGROUND

Arsenic and its inorganic compounds are classified as carcinogenic to humans. Exposures to inorganic arsenic (iAs) in drinking water are associated with both carcinogenic and non-carcinogenic effects. The risk assessment of exposures to low-moderate levels of environmental arsenic (As) is a challenging objective for research and public health. The SEpiAs study, funded by the Italian Ministry of Health (CCM), was carried out in four areas with arsenic pollution prevalently of natural origin, Amiata and Viterbo areas, or of industrial origin, Taranto and Gela.

METHODS

271 subjects (132 men) aged 20-44, were randomly sampled stratifying by area, gender and age classes. Individual data on residential history, socio-economic status, environmental and occupational exposures, lifestyle and dietary habits, were collected through interviews using questionnaire. In urine samples of recruited subjects, the concentration of inorganic arsenic (iAs) and methylated species (MMA, DMA) was measured using inductively coupled mass spectrometer (DRCICP- MS), after chromatographic separation (HPLC). Molecular biomarkers and biomarkers of DNA damage, as well as markers of cardiovascular risk were measured The distributions of iAs and iAs+MMA+DMA were described by area and gender, geometric mean (GM), percentiles and standard deviation (SD). The associations between As species and variables collected by questionnaire were evaluated by multiple regression analysis.

RESULTS

Results showed a high variability of As species within and among areas. Gela and Taranto samples showed higher iAs concentration compared to Viterbo and Amiata. Subjects with iAs>1,5 μg/L or iAs+MMA+DMA>15 μg/L (thresholds suggested by the Italian Society of Reference Values), are 137 (50,6%) and 68 (25,1%), respectively. A positive association between iAs and use of drinking water emerged in the Viterbo sample, between iAs and occupational exposure in the Gela and Taranto samples. Fish consumption was associated with higher iAs concentration in the whole sample, and particularly in men of the Gela sample. Similar results were observed for iAs+MMA+DMA. Subjects with iAs or iAs+MMA+DMA values higher than the 95th percentile were 15 (6Taranto, 5 Gela, 3Viterbo, 1 Amiata). The relationships between iAs and organic species (methylation efficiency ratios) were different between sex in the four areas. The relevance of polymorphisms AS3MT Met287Thr, GST-T1, GST-M1, OGG1 was confirmed. The analysis of carotid intima-media-thickness showed normal values, but higher among man of Viterbo, Taranto and Gela areas.

CONCLUSIONS

Results are informative of exposure to inorganic and organic As in large or at least non-negligible quotas of the samples. The SEpiAs results suggest a further deepening on routes of exposure to arsenic species, and support the recommendation to implement primary prevention measures to reduce population exposure.

The substrate-binding H-site of human glutathione transferase (GST) M2-2 was subjected to iterative saturation mutagenesis in order to obtain an efficient enzyme with the novel epoxide substrate indene 1,2-oxide. Residues 10, 116, and 210 were targeted, and the activities with the alternative substrates, benzyl isothiocyanate and the prodrug azathioprine, undergoing divergent chemical reactions were monitored for comparison. In general, increased activities were found when the smaller residues Gly, Ser, and Ala replaced the original Thr210. The most active mutant T210G was further mutated at position 116, but no mutant showed enhanced catalytic activity. However, saturation mutagenesis of position 10 identified one double mutant T210G/I10C with 100-fold higher specific activity with indene 1,2-oxide than wild-type GST M2-2. This enhanced epoxide activity of 50 μmol min(-1) mg(-1) resulted primarily from an increased k(cat) value (70 s(-1)). The specific activity is 24-fold higher than that of wild-type GST M1-1, which is otherwise the most proficient GST enzyme with epoxide substrates. A second double mutant T210G/I10W displayed 30-fold increased activity with azathioprine, 0.56 μmol min(-1) mg(-1). In both double mutants, the replacement of Ile10 led to narrowed acceptance of alternative substrates. Ile10 is evolutionarily conserved in related class Mu GSTs. Conservation usually indicates preservation of a particular function, and in the Mu class, it would appear that the conserved Ile10 is not necessary to maintain catalytic functions but to prevent loss of broad substrate acceptance. In summary, our data underscore the facile transition between alternative substrate selectivity profiles in GSTs by a few mutations.

Aim: In this case control study involving, 220 human subjects; polymorphisms in xenobiotic metabolizinggenes (GST-M1, -T1 and -P1) and their association to lung cancer risk is being analysed among smokers and nonsmokers.GSTM1 or GSTT1 gene polymorphism and amino acid changes in GSTP1 have been correlated and may beassociated to lung cancer risk. Other factor includes exposure to environmental pollutants and life style choices. Wehave explored gene-gene and gene-environment interaction in the aetiology of lung cancer risk among north Indianpopulation. Patients and Methods: For the study we have collected 120 lung cancer patient blood samples fromKamala Nehru Memorial Cancer Hospital, Allahabad, Uttar Pradesh and 100 matched controls. DNA was isolatedand GST-M1 and - T1 genotyping were assessed by multiplex PCR whereas the GSTP1 polymorphism was analysedusing restriction fragment length polymorphism. The risk of lung carcinogenesis was assessed using logistic regressionanalysis calculating the odd ratio (OR) with 95% confidence interval (CI). Results: The risk of lung carcinogenesiswas three fold higher for null GSTT1 (OR=3.045, 95%CI=1.750-5.301, p-value <0.001) genotype; whereas other twotypes; GSTM1 (OR= 1.342, 95% CI=0.788-2.284, p-value=0.270) and GSTP1 (OR=0.806, 95% CI=0.526-1.236,p-value=0.323) showed no association to lung cancer susceptibility respectively. Smokers diagnosed with lung cancerhad more null genotypes for GSTT1 (OR=4.773, 95%CI=1.939-11.751, p<0.001). The ‘at risk’ genotype combinationGSTM1 (null) /GSTT1 (null) (OR=1.76, 95%CI; 0.920-3.370, p-value=0.03) showed increased susceptibility to lungcancer risk. The genotype combination of GSTT1 (null)/GSTP1 (Ile/Ile) (p=0.009) was associated with increased lungcancer risk. Conclusion: The results of this study suggest that; GSTT1 null genotype were more susceptible for lungcancer risk and smoking increases the susceptibility for lung cancer several folds among the North Indian population.Gene-gene interaction for null genotypes of GSTM1 and GSTT1 were correlated with higher risk of having lung cancer.

OBJECTIVE

The purpose of this research was to characterize CYP2D6, GST-M1 and GST-T1 enzyme expression in human parathyroid tissue, and to determine whether or not there is any association between deficiencies in these enzymes and serum parathyroid hormone concentrations in patients with end-stage renal disease.

METHODS

Surgical human parathyroid tissue was obtained and evaluated by immunohistochemistry for cellular localization of CYP2D6, GST-M1 and GST-T1 and colocalization of CYP2D6 with parathyroid hormone. Blood samples were collected from 328 Caucasian patients with end-stage renal disease for genetic testing of CYP2D6*3, *4, *5, *6, *7 and GST-M1*0 and GST-T1*0 alleles. Clinical chemistry data and serum intact parathyroid hormone (iPTH) concentrations were obtained from patient medical records. In 277 of the patients, the same laboratory performed all clinical tests.

RESULTS

CYP2D6, GST-M1 and GST-T1 were present in human parathyroid tissue. CYP2D6 was colocalized with parathyroid hormone in parathyroid chief cells. Within the end-stage renal disease population, a nonfunctional CYP2D6 genotype was present in 18.2%[95% confidence interval (CI) 8.0, 28.4] of patients in the 1st iPTH concentration quintile (iPTH < 64 pg x mL(-1)), in 0% (95% CI 0, 7.5) of those in the 2nd quintile, in 1.8% (95% CI 0, 9.3) of those in the 3rd quintile, in 9.1% (95% CI 1.5, 16.7) of those in the 4th quintile, and in 16.7% (95% CI 6.8, 26.5) of those in the 5th quintile (iPTH>> 347 pg x mL(-1)) (P = 0.001). Out of 12 CYP2D6-deficient females, seven were in the 1st iPTH concentration quintile and the remaining five were in the 5th quintile. Patients deficient in the GST-M1 and GST-T1 enzymes displayed a far more uniform frequency distribution relative to serum iPTH concentrations.

CONCLUSIONS

The presence of CYP2D6, GST-M1 and GST-T1 in parathyroid cells was observed. An association is reported between a lack of CYP2D6 and iPTH concentrations in newly diagnosed end-stage renal disease patients. Gender and concomitant deficiency in GST-M1 and/or GST-T1 appear to define this association further. It remains to be established whether these associations reflect a cause-effect relationship between deficient expression of metabolizing enzymes and severity of secondary manifestation of renal failure.

OBJECTIVE

This study investigates the effect of multiple factors, including exposure to polycyclic aromatic hydrocarbons (PAHs), lifestyle, genetic polymorphism of cytochrome P450 (CYP)1A1, glutathione transferase (GST)M1, GSTP1, N-acetyltransferase (NAT)2 and gene p53, as well as any family history of cancer, on DNA adduct levels in coke-oven workers.

METHODS

Sixty-five coke-oven workers employed at the largest iron-steel factory in China were recruited for the study. Personal data were collected at the interview. DNA adduct levels in total white blood cells (WBCs) were detected using 32P-postlabeling techniques. Genetic polymorphisms were analyzed by polymerase chain reaction (PCR) methods.

RESULTS

The subjects were divided into low and high exposure groups, according to personal exposure to PAHs. The mean adduct value was 1.57 (range 0.54 to 4.35) per 10(8) nucleotides. A tendency for increased levels of DNA adducts in the high exposure group was observed, compared with the low exposure group (P = 0.07). In the low exposure group, DNA adducts were found to be positively associated with urinary cotinine (r = 0.44, P = 0.01). The rare allele homozygotes of CYP1A1 showed significantly higher DNA adduct levels than those of other CYP1A1 genotypes. Individuals with the NAT2 wild type had significantly increased DNA adduct levels than those with other NAT2 genotypes in the high exposure group. The p53 genetic polymorphism revealed a significantly positive effect on DNA adducts formation. There was a significantly higher adduct level in the subjects with a family history of cancer than those without, in the high exposure category.

CONCLUSIONS

Effects of several variables, such as smoking, genetic polymorphism of 2 CYP1A1, NAT2, and gene p53, and a family history of cancer on DNA adduct levels were found, suggesting that these variables should be considered when evaluating the genotoxic effect of occupational exposure to PAHs using WBCs DNA adducts.

UNASSIGNED

Progression of hepatitis B virus infection (HBV) might be affected by host genetic factors. The present study was undertaken to study the role of glutathione S-transferases (GST)-M1 and T1 gene polymorphisms in different stages of HBV infection: HBV inactive carrier, chronic hepatitis B and cirrhosis, and cryptogenic cirrhosis.

UNASSIGNED

The study population comprised of 170 subjects; 120 cases (HBV inactive carrier, n = 30; HBV related chronic hepatitis, n = 30; HBV related cirrhosis, n = 30; cryptogenic cirrhosis, n = 30) and 50 unrelated healthy adults without liver disease as controls. Analysis of GSTM1 and GSTT1 gene polymorphisms was done by multiplex polymerase chain reaction.

UNASSIGNED

The GSTM1 null genotype was seen more commonly in hepatitis B cirrhosis (n = 21; 70%), chronic hepatitis B (n = 19; 63.33%) and cryptogenic cirrhosis (n = 17; 56.67%) as compared with inactive carrier (n = 9; 30%) and controls (n = 13; 26%). The GSTT1 null genotype was seen less frequently in all the groups, the observed frequencies were controls (n = 7; 14%), inactive carrier (n = 5; 16.67%), chronic hepatitis B (n = 8; 26.67%) and hepatitis B cirrhosis (n = 7; 23.33%). The difference of GSTM1 null genotype frequencies was statistically significant for hepatitis B cirrhosis vs. controls (P = 0.0002), chronic hepatitis B vs. controls (P = 0.002) and cryptogenic cirrhosis vs. controls (P = 0.01). The GSTT1 null genotype was not found to vary significantly between the groups.

UNASSIGNED

The patients with GSTM1 null genotype are at risk of progression of liver disease as the frequency of GSTM1 null genotype was found to be significantly higher in chronic hepatitis B, hepatitis B cirrhosis and cryptogenic cirrhosis as compared with controls.

In view of the controversies surrounding the glutathione-S-transferases (GST) M1/T1-endometriosis association, a meta-analysis of the GSTM1/GSTT1 genetic association studies of endometriosis was performed in Chinese populations. PubMed, Springer Link, OvidSP, and Chinese databases were searched for related studies. A total of nine studies on GSTM1-endometriosis involved 874 cases and 997 controls, and five studies on GSTT1 involved 404 cases and 513 controls were included in this meta-analysis. Overall, the null genotype of GSTM1/GSTT1 was significantly related to endometriosis risk in Chinese populations (GSTM1, OR = 2.21, 95% CI: 1.22-4.01; GSTT1, OR = 2.31, 95% CI: 1.34-3.99). In subgroup analyses stratified by ethnicity and source of controls, the same results were observed in Chinese Han and population-based studies. The sensitivity analysis confirmed the reliability and stability of the meta-analysis. No publication bias was found among studies by Egger's test. In conclusion, our meta-analysis supports that the GSTM1/GSTT1 null genotype might contribute to individual susceptibility to endometriosis in Chinese populations, especially in Chinese Han.

Autism spectrum disorders (ASD) are a group of complex psychiatric disorders, with a proposed gene-environment interaction in their etiology. One mechanism that could explain both the genetic and environmental component is oxidative stress. The aim of our study was to investigate the potential role of common polymorphisms in genes for glutathione transferase A1, M1, T1 and P1 in susceptibility to ASD. We also aimed to explore the possible oxidative stress - specific gene-environment interaction, regarding GST polymorphisms, maternal smoking tobacco during pregnancy (TSDP) and the risk of ASD. This case-control study included 113 children with ASD and 114 age and sex-matched controls. The diagnosis was made based on ICD-10 criteria and verified by Autism Diagnostic Interview - Revised (ADI-R). We investigated GSTA1, GSTM1, GSTP1 and GSTT1 genotypes and explored their individual and combined effects in individuals with ASD. Individual effect of GST genotypes was shown for GSTM1 active genotype decreasing the risk of ASD (OR = 0.554, 95%CI: 0.313-0.983, p = 0.044), and for GSTA1 CC genotype, increasing susceptibility to ASD (OR = 4.132, 95%CI: 1.219-14.012, p = 0.023); the significance was lost when genotype-genotype interactions were added into the logistic regression model. The combination of GSTM1 active and GSTT1 active genotype decreased the risk of ASD (OR = 0.126, 95%CI: 0.029-0.547, p = 0.006), as well as combination of GSTT1 active and GSTP1 llelle (OR = 0.170, 95%CI: 0.029-0.992, p = 0.049). Increased risk of ASD was observed if combination of GSTM1 active and GSTP1 llelle was present (OR = 11.088, 95%CI: 1.745-70.456, p = 0.011). The effect of TSDP was not significant for the risk of ASD, neither individually, nor in interaction with specific GST genotypes. Specific combination of GST genotypes might be associated with susceptibility to ASD, while it appears that maternal smoking during pregnancy does not increase the risk of ASD.

To study the effects of Bacillus lincheniformis feeding frequency on the survival and growth of Haliotis discus hannai abalone, we measured the expression levels of nonspecific immune genes and monitored the anti-Vibrio parahaemolyticus immune reaction. H. discus hannai (shell length: 32.75 ± 2.63 mm, body weight: 4.91 ± 0.34 g) was selected to perform a 70 d laboratory culture experiment including a 14 d V. parahaemolyticus artificial infection experiment. The control group (C) was fed normal commercial feed every day. The M1 experimental group was given experimental feed and basal feed on alternating days until the end of the experiment. The M2 experimental group was given experimental feed for 4 d and basal feed for 3 d, and this cycle was repeated every 7 d until the end of the experiment. The M3 experimental group was given experimental feed for 2 d and basal feed for 5 d, and this cycle was repeated every 7 d until the end of the experiment. The M4 group was continuously given experimental feed for the duration of the experiment. The concentration of added B. lincheniformis in each experimental group was 10⁵ cfu/g (according to the quantity of viable bacteria). The specific growth rate (as measured by body weight) and the feed conversion efficiency of the abalone in M1 and M2 were significantly higher than those in M4 and C (P < 0.05). The cellulose and lipase activities of abalone in M1, M2 or M4 were significantly higher than those in M3 or C (P < 0.05). The acid phosphatase, superoxide dismutase, total haemocyte counts, O₂^- levels generated by respiratory bursts, and the expression levels of Mn-SOD, TP_x, GST_s and GST_m in abalone in the M2 group were significantly higher than those in any other feeding frequency group (P < 0.05). At the end of the V. parahaemolyticus infection, the cumulative mortality of the abalone in M2 was significantly lower than that in any other group (P < 0.05). Consequently, given the growth advantages and the enhancement of immune function, the feeding plan in which B. lincheniformis was applied for 3 d per week, and basal feed was then applied for 4 d, did not lead to a high level of immune reaction, immune fatigue or waste of resources, but increased the growth rate of individuals and their resistance to V. parahaemolyticus infection.

BACKGROUND

Hepatotoxicity is a serious adverse effect of antituberculosis treatment (ATT). Glutathione S-transferase (GST) is involved in the detoxification of toxic metabolites produced as a result of ATT, increased oxidative stress and decreased antioxidant levels, and differences in the GST polymorphism may be one of the causes of ATT-induced hepatotoxicity.

OBJECTIVE

This study was undertaken to study the relationship among antioxidant status, oxidative stress and GST gene polymorphisms in the development of ATT-induced hepatotoxicity in Indian patients.

METHODS

Two hundred fifty TB patients attending clinics in the Gastroenterology and Thoracic Department, PGIMER, Chandigarh, were enrolled. Liver marker enzymes, markers of oxidative stress, levels of antioxidants and identification of GSTT1, GSTM1 and GSTP polymorphisms were performed using standard protocols.

RESULTS

Of the 250 patients, 160 were males. Of the 160 males, 18 (11.3 %) had ATT-induced hepatotoxicity and 142 no hepatotoxicity, while of 90 females, 12 (13.3 %) had hepatotoxicity and 78 no hepatotoxicity. Patients who developed ATT-induced hepatotoxicity had significantly higher oxidative stress compared to those who did not develop hepatotoxicity at between 1 and 2 months of treatment. Among antioxidants, catalase did not show any significant difference at 2 and 4 months of treatment. The presence of <em>GST</em>M1 was higher in hepatotoxicity patients as compared to non-hepatotoxicity patients, while <em>GST</em>T1 and <em>GST</em>1/M1 were lower.

CONCLUSIONS

Therefore, in this study, the possible association of oxidative stress with ATT-induced hepatotoxicity was observed. A role of the GST polymorphism in ATT-induced hepatotoxicity was also found and thus could possibly identify the groups at highest risk of developing ATT-induced hepatotoxicity.

MRL-1, a cannabinoid receptor-1 inverse agonist, was a member of a lead candidate series for the treatment of obesity. In rats, MRL-1 is eliminated mainly via metabolism, followed by excretion of the metabolites into bile. The major metabolite M1, a glutathione conjugate of MRL-1, was isolated and characterized by liquid chromatography/mass spectrometry and NMR spectroscopic methods. The data suggest that the t-butylsulfonyl group at C-2 of furopyridine was displaced by the glutathionyl group. In vitro experiments using rat and monkey liver microsomes in the presence of reduced glutathione (GSH) showed that the formation of M1 was independent of NADPH and molecular oxygen, suggesting that this reaction was not mediated by an oxidative reaction and a glutathione S-transferase (GST) was likely involved in catalyzing this reaction. Furthermore, a rat hepatic GST was capable of catalyzing the conversion of MRL-1 to M1 in the presence of GSH. When a close analog of MRL-1, a p-chlorobenzenesulfonyl furopyridine derivative (MRL-2), was incubated with rat liver microsomes in the presence of GSH, p-chlorobenzene sulfinic acid (M2) was also identified as a product in addition to the expected M1. Based on these data, a mechanism is proposed involving direct nucleophilic addition of GSH to sulfonylfuropyridine, resulting in an unstable adduct that spontaneously decomposes to form M1 and M2.

The emerald ash borer, Agrilus planipennis Fairmaire is a recently discovered invasive insect pest of ash, Fraxinus spp. in North America. Glutathione-S-transferases (GST) are a multifunctional superfamily of enzymes which function in conjugating toxic compounds to less toxic and excretable forms. In this study, we report the molecular characterization and expression patterns of different classes of GST genes in different tissues and developmental stages plus their specific activity. Multiple sequence alignment of all six A. planipennis GSTs (ApGST-E1, ApGST-E2, ApGST-E3, ApGST-O1, ApGST-S1 and ApGST-μ1) revealed conserved features of insect GSTs and a phylogenetic analysis grouped the GSTs within the epsilon, sigma, omega and microsomal classes of GSTs. Real time quantitative PCR was used to study field collected samples. In larval tissues high mRNA levels for ApGST-E1, ApGST-E3 and ApGST-O1 were obtained in the midgut and Malpighian tubules. On the other hand, ApGST-E2 and ApGST-S1 showed high mRNA levels in fat body and ApGST-μ1 showed constitutive levels in all the tissues assayed. During development, mRNA levels for ApGST-E2 were observed to be the highest in feeding instars, ApGST-S1 in prepupal instars; while the others showed constitutive patterns in all the developmental stages examined. At the enzyme level, total GST activity was similar in all the tissues and developmental stages assayed. Results obtained suggest that A. planipennis is potentially primed with GST-driven detoxification to metabolize ash allelochemicals. To our knowledge this study represents the first report of GSTs in A. planipennis and also in the family of wood boring beetles.

Multiple sclerosis (MS) is an inflammatory disease with unknown etiology. Oxidative stress has been demonstrated to play a role in pathological and inflammatory mechanisms of MS. Cells activate antioxidant processes in response to oxidative stress. Glutathione is one of the antioxidant agents in the brain and serves as a cofactor for glutathione s-transferase (GST) enzymes for detoxifying nerve cells. Among different classes of GST, GSTM1 and GSTT1 are associated with the loss of function due to structural homozygous deletion. The aim of this study is to investigate GSTM1 and GSTT1 null genotypes in an Iranian population. In this study, 270 patients and 250 healthy controls were investigated. Patient's disabilities were assessed by Kurtzke Expanded Disability Status Scale (EDSS) and genotypes were determined by multiplex PCR. Association between genotype and MS, type of MS, gender, and inability level were surveyed. The findings demonstrated a highly significant association between the null genotypes and MS (OR = 6.89 for M1/T1). The combination of two genotypes increased the risk of MS by 6.8 times. The null genotypes were found to be more frequent in women than in men. Moreover, a significant association was observed between the null genotype and EDSS 6-10 (OR = 3.199). No significant association was noticed between MS type and the studied genotypes. According to this study, it can be proposed that people with GSTM1 and GSTT1 deletions are at a higher risk for developing MS, which can be due to a decrease in enzymatic activity and their levels in nerve cells and the brain.

The breast cancer susceptibility gene (BRCA2) is localized mainly in the nucleus where it plays an important role in DNA damage repair. Some BRCA2 protein is also present in the centrosome. Here, we demonstrate that BRCA2 interacts with plectin, a cytoskeletal cross-linker protein, and that this interaction controls the position of the centrosome. Phosphorylation of plectin by cyclin-dependent kinase 1/cyclin B (CDK1/CycB) kinase has been reported to abolish its cross-linking function during mitosis. Here, we induced phosphorylation of plectin in prepared fractions of HeLa cells by adding activated CDK1/CycB kinase. Consequently, there was significant dissociation of the centrosome from the nuclear membrane. Plectin has six homologous ankyrin-like repeat domains (termed PLEC M1-M6). Using a pull-down assay, we found that GST-PLEC M1 and a GST-C-terminal region fusion protein (which comprised PLEC M6, along with an adjacent vimentin site) interacted with BRCA2. Since each PLEC module exhibits high homology to the others, the possibility of all six domains participating in this interaction was indicated. Moreover, when PLEC M1 was overexpressed in HeLa cells, it competed with endogenous plectin and inhibited the BRCA2-plectin interaction. This inhibitory effect resulted in dissociation of the centrosomes from the nucleus and increased the rate of micronuclei formation which may lead to carcinogenesis. In addition, when either BRCA2 or plectin was suppressed by the appropriate siRNA, a similar change in centrosomal positioning was observed. We suggest that the BRCA2-plectin interaction plays an important role in the regulation of centrosome localization and also that displacement of the centrosome may result in genomic instability and cancer development.

OBJECTIVE

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.

OBJECTIVE

This study was conducted to investigate whether insertion/deletion (I/D) polymorphism of angiotensin-converting enzyme (ACE) gene and polymorphisms in glutathione S-transferase (GST) M1 and T1 genes are associated with increased risk for preeclampsia.

METHODS

Sixty-three patients with hypertensive disorder of pregnancy and 85 controls were evaluated in a prospective case-control study. All subjects were genotyped by polymerase chain reaction (PCR) followed by agarose gel electrophoresis.

RESULTS

Allele frequencies of ACE gene I/D polymorphism were found significantly different between preeclampsia and the control groups (p = 0.001). Differences in genotype frequencies of ACE gene I/D polymorphism between the two groups were statistically significant (p = 0.004). Individuals homozygous for D allele were more likely to develop preeclampsia (OR = 2.29; 95% CI, 1.39-3.79), whereas heterozygous individuals were not at increased risk (OR = 0.92; 95% CI, 0.56-1.49), compared to individuals homozygous for I allele. The differences in frequencies of functional and null alleles of GSTM1 and GSTT1 genes between the two groups were not significant (p = 0.46 and p = 0.44, respectively).

CONCLUSIONS

ACE gene DD genotype was found to be associated with increased risk of preeclampsia development, whereas the authors did not find any significant relationship with polymorphisms of the GSTM1 and GSTT1 genes and preeclampsia.

OBJECTIVE

Persistent hepatitis B virus (HBV) infection often leads to the development of chronic hepatitis and cirrhosis. The role of host genetic factors in chronic HBV infection is not fully understood. We studied the influence of glutathione S-transferase (GST) M1, T1, and P1 polymorphisms in patients with different stages of HBV infections.

METHODS

The sample population included 41 HBV normal carriers, 37 patients with chronic hepatitis, and 38 patients with cirrhosis (infected with HBV) compared to a control group (n = 59). PCR-based procedures were performed in the studied populations to confirm the genotypes of GSTT1, M1, and P1. Odds ratio analysis tests were used for statistical evaluation.

RESULTS

We found that the frequency of GSTP1-Val (105)/Val (105) genotype was significantly higher in patients with liver cirrhosis (27%) than HBV normal carriers (2.4%; OR 14.8, 95% CI 1.8-122.5) and the frequency GSTP1-Val (105)/Ile (105) genotype was significantly higher in patients with liver cirrhosis (59.5%) than HBV normal carriers (19.5%; OR 6.1, 95% CI 2.1-16.7). The genotype GSTP1-Val (105)/Val (105) was more frequent in patients with chronic hepatitis (19.4%) than HBV normal carriers (2.4%; OR 9.65, 95% CI 1.1-82.8). Patients with cirrhosis also had a higher frequency of the GSTM1 null genotype (71.1%) than HBV normal carriers (27.5%; OR 6.5, 95% CI 2.4-17.4) and the GSTM1 null genotype was more frequent in patients with chronic hepatitis (64.9%) than HBV normal carriers (27.5%OR 4.9, 95% CI 1.8-12.8). The frequency of GSTT1 genotype was similar in all groups.

CONCLUSIONS

These results suggest that in HBV infection, inheritance of the null GSTM1 and GSTP1-Val (105) polymorphisms involves a host genetic factor that is relevant to disease progression.

Age-associated differences in the response of the initiation and promotion of hepatocellular carcinogenesis in the rat were analyzed. Male Wistar rats 5 and 18 months-old were used throughout. They underwent an experimental design of multistage model of hepatocarcinogenesis: hepatic cells were initiated with the complete carcinogen Aflatoxin B1 (0.5mg/Kg b.w.) and the promotion was performed through a combined treatment of proliferation (partial hepatectomy, 65%) and administration of the tumorigenic promoter phenobarbital (0.1% in drinking water for 21 days). After the treatment, rats were sacrificed and the following parameters were determined: activity and subunit composition of the glutathione S-transferase enzyme system, the number of liver preneoplastic foci and the proliferation cell index. The combined treatment (initiation + promotion) lowered the expression of the mu class GST (rGST M1, rGST M2). The inhibition in rGST M2 in old animals (which in basal conditions had already been lower) was significant. On the other hand, the treatment increased the alpha class GST (rGST A, rGST A3). The number of preneoplastic foci was higher in old rats (number of foci/cm(2): 6.9+/-0.3 vs 3.9+/-0.3 in young rats, p< 0.05). The proliferation cell index did not show age-related differences. Because rGST M2 deficiency coexisted with induced expression of alpha class, the livers would be resistant to some toxic insults, being selectively sensitive to potentially genotoxic substances for which M2 is an essential detoxification pathway. The transition to a rGST M2-deficient phenotype during aging could induce higher responsiveness to genotoxic effects, and might favor the likelihood of further progression, indicating a higher susceptibility of aged animals to the development of carcinogenesis.

BACKGROUND

Busulfan is a key compound in myeloablative chemotherapy before hematopoietic stem-cell transplantation in children. Genetic polymorphisms of glutathione S-transferase (GST), which is involved in the metabolism of busulfan, have been implicated in interindividual variability in busulfan pharmacokinetics. Development of a rapid and simplified method for polygenic analysis of GST may facilitate large pharmacogenetic studies and clinical application of individualized busulfan dose adjustment. We previously introduced an effective PCR method for analyzing multiple genes using a small amount of DNA, termed 'TotalPlex amplification'.

OBJECTIVE

The aim of this study was to extend the application of the TotalPlex method to the specific GST gene families (A1, P1, M1, and T1) that are related to busulfan metabolism, and thereby facilitate pharmacogenetic analysis of GST polymorphisms.

METHODS

Seven genetic polymorphisms (GSTA1 promoter -52G>A, -69C>T, -567T>G, and -631T>G; GSTP1 313A>G; GSTM1 deletion; and GSTT1 deletion) were analyzed by multiplex PCR and genotyping, and the genotyping results from TotalPlex were verified with those from uniplex PCR.

RESULTS

Using five pairs of specific bulging-specific primers, seven specific gene fragments were successfully amplified by multiplex amplification coupled to a multiplexed bead array detection system, with a smaller amount of DNA and a shorter process time than is needed for the conventional approach. The genotypes of seven loci from 30 different genomic DNA samples derived using the multiplex system were consistent with the results of standard genotyping methods.

CONCLUSIONS

Our multiplex system provides a fast, inexpensive, and accurate method of detecting multiple GST polymorphisms (GSTA1, GSTP1, GSTM1, and GSTT1).

OBJECTIVE

The aim of this study was to investigate whether the glutathione S-transferase M1 (GSTM1) and T1 (GSTT1) gene polymorphisms contributed to development of gestational diabetes mellitus (GDM).

METHODS

Fifty women with diagnosis of GDM and 50 control individuals without GDM or altered glucose intolerance during their pregnancy were enrolled in the study. Multiplex polimerase chain reaction-restriction fragment length polymorphism method was applied to determine the GSTM1 and GSTT1 gene polymorphisms. Genotypes were determined according to bands detected with the agarose gel electrophoresis.

RESULTS

The difference in the frequencies of GSTM1 null genotypes between GDM and control groups was not statistically significant (60% and 54%, respectively). There was no statistically significant difference between GDM and control groups with respect to GSTT1 null genotype rates (22% and 20%, respectively).There was no statistically significant difference between GDM and control groups with respect to GSTT1 null genotype rates (22% and 20%, respectively).

CONCLUSIONS

This study shows no association between GST gene polymorphisms and GDM.

OBJECTIVE

To explore the possible association of polymorphisms of glutathione S-transferases T1, M1 genes and leukemia susceptibility.

METHODS

AS-PCR procedure was applied to determine the GSTs genotypes in a group of leukemia patients (n=61) in Shanghai area. The genotype frequencies in the leukemia patients and normal controls (183 healthy residents in the same city) were compared. Stratification with leukemia types, age and gender was made for further comparison.

RESULTS

The frequencies of GSTT1 0/0 genotype and GSTT1 0/0-GSTM1 0/0 combined genotype were higher in leukemia patients than in controls, and the differences were significant. When stratified with age and gender, this trend still existed in the male ALL patients and in younger ALL patients (age < or = 30).

CONCLUSIONS

Individuals who bear GSTT1 0/0 genotype or GSTT1 0/0-GSTM1 0/0 combined genotypes are more susceptible to leukemia, especially for male and younger carriers.

OBJECTIVE

Oxidative stress plays an important role in the pathogenesis of type 1 diabetes mellitus (T1DM). To evaluate the association of glutathione S-transferase mu 1 (GST M1) and glutathione S-transferase theta 1 (GST T1) polymorphisms with development of T1DM and disease-related risk factors.

METHODS

Measurement of fasting glucose, serum creatinine, lipid profile, and glycosylated hemoglobin (HbA1c), as well as evaluation of GST T1 and M1 genetic polymorphisms using polymerase chain reaction were done in 64 diabetic children and 41 controls.

RESULTS

The diabetic group had significantly higher fasting glucose, HbA1c, and cholesterol levels. GST T1 null genotype was more frequent in the diabetic than the control group with 4.2-fold increased risk of T1DM (odds ratio=4.2; 95% confidence interval=1.6-11.5; p=0.03). Significant positive associations were found with lipid profile, HbA1c, and duration of illness but not with age, age at onset, and body mass index.

CONCLUSIONS

Gene polymorphisms of the enzyme GST are associated with development of T1DM and disease-related risk factors.