Phospholipase C epsilon 1 (PLCE1) haplotypes are associated with increased risk of gastric cancer in Kashmir Valley

BACKGROUND/AIM

Phospholipase C epsilon 1 (PLCE1) plays a crucial role in carcinogenesis and progression of several types of cancers. A single nucleotide polymorphism (SNP, rs2274223) in PLCE1 has been identified as a novel susceptibility locus. The aim of the present study was to investigate the role of three potentially functional SNPs (rs2274223A > G, rs3765524C > T, and rs7922612C > T) of PLCE1 in gastric cancer patients from Kashmir Valley.

PATIENTS AND METHODS

The study was conducted in 108 GC cases and 195 healthy controls from Kashmir Valley. Genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism method. Data were statistically analyzed using c2 test and logistic regression models. A P value of less than 0.05 was regarded as statistically significant.

RESULTS

The frequency of PLCE1 A2274223C3765524T7922612, G2274223C3765524T7922612 , and G2274223T3765524C7922612 haplotypes were higher in patients compared with controls, conferred high risk for GC [odds ratio (OR) =6.29; P = 0.001; Pcorr = 0.003], (OR = 3.23; P = 0.011; Pcorr = 0.033), and (OR = 5.14; P = 0.011; Pcorr = 0.033), respectively. Smoking and salted tea are independent risk factors for GC, but we did not find any significant modulation of cancer risk by PLCE1 variants with smoking or excessive consumption of salted tea.

CONCLUSION

These results suggest that variation in PLCE1 may be associated with GC risk in Kashmir Valley.

Muscular dystrophies

Muscular dystrophies are a heterogeneous group of inherited disorders characterized by progressive muscle wasting and weakness. Majority of genes and their protein products responsible for the dystrophies have been identified in recent years. Using molecular studies, now it is possible to establish a precise diagnosis, provide prognosis, detect preclinical cases, identify carriers, and offer prenatal diagnostic testing. Molecular genetic approaches also seem to offer the best prospect for developing effective treatments in the future.

Signal transducers and activators of transcription (STATs) gene polymorphisms related with susceptibility to rheumatic heart disease in north Indian population

Rheumatic heart disease (RHD) is the most serious complication of heart that comprises inflammatory reactions in heart valves. Cytokines play a critical role in triggering inflammatory reactions and they activate the Janus Kinase/Signal Transducers and Activators of Transcription (JAK/STAT) signaling pathway. Altered signals of STATs play important roles in the balance between proinflammatory and anti-inflammatory cytokines in inflammatory diseases. The aim of the present study was to investigate for the association of polymorphisms related with STAT genes, i.e. STAT3 (rs4796793 C/G) and STAT5b (rs6503691 C/T) with the pathogenesis of RHD. This case-control association study involved 300 healthy controls and 400 RHD patients from North Indian Population. We categorized RHD patients into two subgroups based on involvement of heart valves, mitral valve lesion alone (MVL), and combined valve lesions including mitral valve (CVL). Genotyping was done by RFLP/Taqman probes. We observed that STAT3 CG and GG genotypes were significantly associated with RHD (p=0.030 and p=0.014 respectively), STAT5b CT and TT genotypes were also significantly associated with RHD (p≤0.001). Haplotype analysis revealed that minor alleles of both the variants (Grs4796793Trs6503691) were significantly associated (p<0.0001) with increased risk of the disease susceptibility irrespective of gender or age of onset of the disease. However, the polymorphisms were not involved in severity of RHD as both MVL and CVL patients were equally affected. STAT Grs4796793Trs6503691 carriers may have reduced production of STAT3 leading to damage of heart valves. Thus, STAT genes polymorphisms may be useful markers for the identification of individuals with high risk of RHD in the susceptible population.

Genetic association of interleukin-1 haplotypes with gastritis and precancerous lesions in North Indians

BACKGROUND

We evaluated the association of functional variants of IL-1 genes with the development of gastritis and precancerous lesions, which are known to be influenced by inflammatory response against Helicobacter pylori.

METHODS

After upper gastrointestinal (GI) endoscopy, 120 patients with gastritis were tested for H. pylori infection using rapid urease test, modified Giemsa staining and IgG anti-CagA ELISA. All patients and 243 healthy controls were genotyped for IL-1B (-511 C/T) and IL-IRN (VNTR) genes using PCR-RFLP/PCR.

RESULTS

IL-1B: (-511 C/T) genotype/allele were not associated with gastritis. IL-1RN 1/2 genotype carriers had susceptibility to gastritis (p=0.025, OR=1.7). Individuals with the IL-1RN 1/1 genotype (p=0.05, OR=0.65) and IL-1B -511*T-IL-1RN *1 haplotype were at low risk for gastritis (p=0.043, OR=0.72). High secretor haplotype combinations (C1-/T2+, C1-T1+ and T1+/T2+) did not influence neutrophilic infiltration, glandular atrophy or intestinal metaplasia.

CONCLUSIONS

We identified that individuals with the IL-1RN 1/2 genotype had increased risk for gastritis. IL-1B -511*T-IL-1RN *1 (T1) haplotype carriers were at decreased risk for gastritis and no significant association was observed for precancerous lesions in North Indians.

Null association of NQO1 609C>T and NQO2 -3423G>A polymorphisms with susceptibility and prognosis of Esophageal cancer in north Indian population and meta-analysis

INTRODUCTION

NAD(P)H:quinone oxidoreductase 1 (NQO1) and NRH:quinone oxidoreductase 2 (NQO2), involved in detoxification of environmental carcinogens and activation of chemotherapeutic agents, are supposed to play critical role in carcinogenesis. So, we aimed to investigate the association of NQO1 609C>T and NQO2 -3423G>A polymorphisms with susceptibility and prognosis of Esophageal cancer (EC) in north Indian population. We also performed Meta analysis of published literatures on NQO1 609C>T polymorphism to systematically evaluate its association with EC.

METHODS

We genotyped NQO1 609C>T and NQO2 -3423G>A polymorphisms in 200 incident EC cases (including 150 follow-up cases) and 200 controls using PCR RFLP based methods. Binary logistic regression was applied for risk estimation, while Kaplan Meier and Cox regression tests were applied for survival analysis. All Meta analysis tests were performed using MIX 2.0 software.

RESULTS

The present study did not find any significant association of NQO1 609C>T and NQO2 -3423G>A polymorphisms with susceptibility to EC or its clinical phenotypes (histopathology, tumor location or lymph node metastasis) or interactions with lifestyle risk factors (tobacco usage, smoking, alcohol habit and occupational exposures). Meta analysis of NQO1 polymorphism also indicated null association of the polymorphism with EC overall or with cancer cases stratified by tumor histopathology/ethnicity. Moreover, no prognostic implication of both polymorphisms was observed in EC.

CONCLUSION

NQO1 609C>T and NQO2 -3423G>A polymorphisms do not seem to play any significant role in susceptibility or prognosis of EC in north Indian population and results of Meta-analysis further reinforces null association of NQO1 609C>T polymorphism with EC susceptibility.

Effect of latent iron deficiency on GABA and glutamate neuroreceptors in rat brain

Eight weeks of latent iron deficiency in weaned female rats of Sprague Dawley strain maintained on experimental low-iron diet (18-20 mg/kg) did not significantly change the gross body, weight and tissue weights of brain and liver. Packed cell volume (PCV) and hemoglobin concentration remained unaltered. However, non-heme iron content in liver and brain decreased significantly (p<0.001). The activities of glutamate dehydrogenase, glutamic acid decarboxylase, and GABA-transaminase (GABA-T) in brain decreased by 15%, 11.4% and 25.7% respectively. However, this decrease was not statistically significant. Binding of(3)H Muscimol at pH 7.5 and 1 mg protein/assay increased by 143% (p<0.001) in synaptic vesicular membranes from iron-deficient rats as compared to the controls.(3)H glutamate binding to the synaptic vesicles was also carried out under similar condition. However, the L-glutamate binding was reduced by 63% in the vesicular membranes of iron deficient animals. These studies indicate that iron plays important functional role in both excitatory and inhibitory neurotransmitter receptors.

Quantitative assessment of CD44 genetic variants and cancer susceptibility in Asians: a meta-analysis

CD44 is a well-established cancer stem cell marker playing a crucial role in tumor metastasis, recurrence and chemo-resistance. Genetic variants of CD44 have been shown to be associated with susceptibility to various cancers; however, the results are confounding. Hence, we performed a meta-analysis to clarify these associations more accurately. Overall, rs13347 (T vs. C: OR=1.30, p=<0.004, pcorr=0.032; CT vs. CC: OR=1.29, p=0.015, pcorr=0.047; TT vs. CC: OR=1.77, p=<0.000, pcorr=0.018; CT+TT vs. CC: OR=1.34, p=<0.009, pcorr=0.041) and rs187115 (GG vs. AA: OR=2.34, p=<0.000, pcorr=0.025; AG vs. AA: OR=1.59, p=<0.000, pcorr=0.038; G vs. A allele OR=1.56, p=0.000, pcorr=0.05; AG+GG vs. AA: OR=1.63, p=<0.000, pcorr=0.013) polymorphisms were found to significantly increase the cancer risk in Asians. On the other hand, rs11821102 was found to confer low risk (A vs. G: OR=0.87, p=<0.027, pcorr=0.04; AG vs. GG: OR=0.85, p=<0.017, pcorr=0.01; AG+AA vs. GG: OR=0.86, p=<0.020, pcorr=0.02). Based on our analysis, we suggest significant role of CD44 variants (rs13347, rs187115 and rs11821102) in modulating individual's cancer susceptibility in Asians. Therefore, these variants may be used as predictive genetic biomarkers for cancer predisposition in Asian populations. However, more comprehensive studies involving other cancers and/or populations, haplotypes, gene-gene and gene-environment interactions are necessary to delineate the role of these variants in conferring cancer risk.

Generalized Multifactor Dimensionality Reduction (GMDR) Analysis of Drug-Metabolizing Enzyme-Encoding Gene Polymorphisms may Predict Treatment Outcomes in Indian Breast Cancer Patients

BACKGROUND

Prediction of response and toxicity of chemotherapy can help personalize the treatment and choose effective yet non-toxic treatment regimen for a breast cancer patient. Interplay of variations in various drug-metabolizing enzyme (DME)-encoding genes results in variable response and toxicity of chemotherapeutic drugs. Generalized multi-analytical (GMDR) approach was used to determine the influence of the combination of variants of genes encoding phase 0 (SLC22A16); phase I (CYP450, NQO1); phase II (GSTs, MTHFR, UGT2B15); and phase III (ABCB1) DMEs along with confounding factors on the response and toxicity of chemotherapeutic drugs in breast cancer patients.

METHODS

In an Indian breast cancer patient cohort (n = 234), response to neo-adjuvant chemotherapy (n = 111) and grade 2-4 toxicity to chemotherapy were recorded. Patients were genotyped for 19 polymorphisms selected in four phases of DMEs by PCR or PCR-RFLP or Taqman allelic discrimination assay. Binary logistic regression and GMDR analysis was performed. Bonferroni test for multiple comparisons was applied, and p value was considered to be significant at <0.025.

RESULTS

For ABCB1 1236C>T polymorphism, CT genotype was found to be significantly associated with response to NACT in uni-variate and multi-variate analysis (p = 0.018; p = 0.013). The TT genotype of NQO1 609C>T had a significant association with (absence of) grade 2-4 toxicity in uni-variate analysis (p = 0.021), but a non-significant correlation in multi-variate analysis. In GMDR analysis, interaction of CYP3A5*3, NQO1 609C>T, and ABCB1 1236C>T polymorphisms yielded the highest testing accuracy for response to NACT (CVT = 0.62). However, for grade 2-4 toxicity, CYP2C19*2 and ABCB1 3435C>T polymorphisms yielded the best interaction model (CVT = 0.57).

CONCLUSION

This pharmacogenetic study suggests a role of higher order gene-gene interaction of DME-encoding genes, along with confounding factors, in determination of treatment outcomes and toxicity in breast cancer patients. This can be used as a potential objective tool for individualizing breast cancer chemotherapy with high efficacy and low toxicity.

Association of genetic variants of xenobiotic and estrogen metabolism pathway (CYP1A1 and CYP1B1) with gallbladder cancer susceptibility

Gallbladder carcinoma is a highly aggressive cancer with female predominance. Interindividual differences in the effectiveness of the activation/detoxification of environmental carcinogens and endogenous estrogens may play a crucial role in cancer susceptibility. The present study included 410 patients with carcinoma of the gallbladder (GBC) and 230 healthy subjects. This study examined association of CYP1A1-MspI, CYP1A1-Ile462Val, and CYP1B1-Val432Leu with GBC susceptibility. CYP1A1-MspI [CC] and CYP1A1-Ile462Val [iso/val] genotypes were found to be significantly associated with GBC (p=0.006 and p=0.03, respectively), as compared to healthy controls, while CYP1B1-Val432Leu was not associated with GBC. The CYP1A1 haplotype [C-val] showed a significant association with GBC (p=0.006). On stratification based on gender, the CYP1A1-MspI [CC] genotype showed an increased risk of GBC in females (p=0.018). In case-only analysis, tobacco users with CYP1A1-MspI [CT] genotypes were at a higher risk of GBC (p=0.008). Subdividing the GBC patients on the basis of gallstone status, the CYP1A1 haplotype [C-val] imparted a higher risk in patients without stones when compared to controls (p=0.001). The results remained significant even after applying Bonferroni correction. Multivariate analysis revealed an increased risk of CYP1A1 iso/val and val/val genotypes in GBC patients having BMI >25 (p=0.021). The CYP1A1 polymorphisms may confer increased risk of GBC, probably due to impaired xenobiotic or hormone metabolism through a gallstone-independent pathway.

Comparative study of GST polymorphism in relation to age in COPD and lung cancer

INTRODUCTION

Glutathione-S-transferase is involved in detoxification of xenobiotic compounds. GSTs gene polymorphisms have been considered as a potential modifier for the respiratory disease. COPD is a chronic inflammatory disease of the lungs, which progresses very slowly and the majority of patients are therefore elderly, and few study suggested that age is major risk factor for cancer. Whether age in metabolism of phases 2 enzyme gene polymorphisms GSTT1 and GSTM1 in Northern Indian COPD and lung cancer patients.

MATERIALS AND METHODS

We have enrolled lung cancers, COPD patients and for the comparison we enrolled controls. Peripheral blood of COPD and lung cancer patients was taken after spirometry evaluation and histopathology. All genotyping were done by PCR-RFLP method. Independent sample t-test was performed to compare the mean values of continuous data. Statistical significance of differences in genotype frequencies between patients and controls was estimated by the chi-square two test.

RESULTS

GSTM1 null polymorphism was found to be significantly higher in COPD patients as compared with healthy controls (OR= 2.08; 95%; CI= 1.40-3.09; p= 0.0001), but there were no significant differences polymorphisms of GSTT1 null patients and healthy controls. In lung cancer GSTT1 null was found significantly associated (OR= 1.87; 95%; CI= 1.25-2.80; p= 0.002) however GSTM1 null was not associated with lung cancer patients. In subgroup analysis, we found GSTM1 Null significantly associated between age 46-65 years in COPD patients and healthy controls (62.2%/37.8%, OR= 3.20; 95%; CI= 1.97-5.18; p= 0.001), In lung cancer and controls (55.6%/44.4% OR= 1.07; 95% CI= 0.68-1.69; p= 0.774).

CONCLUSION

The effects of the GSTM1 null genotype seemed strong association with COPD and GSTT1 null genotype with lung cancer patients. GSTM1 null genotype is associated with an increased risk of COPD, especially in middle age.

Expression of desmin cDNA in PtK2 cells results in assembly of desmin filaments from multiple sites throughout the cytoplasm

The assembly of intermediate filaments into a cytoplasmic network was studied by microinjecting into the nuclei and cytoplasms of PtK2 cells, plasmids that contained a full length desmin cDNA and an RSV promoter. Immunofluorescence was used to monitor the expression of desmin and its integration into the cells' vimentin intermediate filament network. We found that the expressed desmin co-localized with filaments of vimentin just as it does with fluorescently labelled desmin is microinjected into the cytoplasm of PtK2 cells. As early as two hours after microinjection of the plasmids, small discrete dots and short fragments of desmin could be detected throughout the cytoplasm of the cells. This initial distribution of desmin was superimposed on the filamentous pattern of vimentin in the cells. At 8 hours after microinjection of the plasmids, some of the desmin was present in long filaments that were coincident with vimentin filaments. By 18 hours, most of the desmin was in a filamentous network co-localizing with vimentin. There was no indication that desmin assembly began in the perinuclear region and proceeded toward the cell periphery. In some cells, excessively high levels of desmin were expressed. In these cases, overexpression led to clumping of desmin filaments as well as to an accumulation of diffusely distributed desmin protein in the center of the cells. This effect was apparent at approximately 18 hours after introduction of the plasmid. The native vimentin filaments in such cells were also aggregated around the nucleus, co-localizing with desmin. The microtubule networks in all injected cells appeared normal; microtubules were extended in typical arrays out to the periphery of the cells.

Association of adrenergic receptor gene polymorphisms in gallbladder cancer susceptibility in a North Indian population

PURPOSE

Gallbladder cancer (GBC), the most common gastrointestinal and biliary tract malignancy, often coincides with gallstone disease (GSD). The genetic variants of adrenergic receptor (ADR) have been previously reported to be associated with hypomotility disorder of cardiovascular system and GSD. Since GSD may function as GBC precursor, the present study aimed to investigate the association of common functional genetic variants of ADRA2A C-1291G, ADRβ3 T190C or Trp64Arg, and ADRβ1 C1165G or Arg389Gly with GBC and GSD susceptibility.

METHODS

The present study included a total of 400 histologically confirmed GBC, 230 GSD, and 268 healthy controls. The ADRA2A C-1291G, ADRβ3 T190C, and ADRβ1 C1165G polymorphisms were determined by PCR-RFLP. Statistical analysis was performed by using SPSS version 16.

RESULTS

ADRβ3 T190C polymorphism was significantly associated with increased risk of GBC (CT: Pcorr = 0.015, OR 2.87; CC: Pcorr = 0.038, OR 10.33; C allele: Pcorr = 0.014, OR 2.7; CT + CC: Pcorr = 0.017, OR 3.05). These associations existed even after gallstone and gender stratification. Similarly, ADRβ3 T190C polymorphism was also associated with GSD risk, though limited only to female GSD patients. In contrary, ADRA2A C-1291G conferred a marginally increased risk only in GSD patients. ADRβ1 C1165G polymorphism was not associated with GBC and GSD susceptibility when compared to controls.

CONCLUSION

ADRβ3 T190C polymorphism is significantly associated with GBC and GSD susceptibility. The ADRβ3 T190C may be involved in the pathophysiology of GBC by both gallstone-dependent pathway and by some other independent mechanisms.

Influence of cytokine gene polymorphism on the risk of rheumatic heart disease - A meta-analysis

RHD is an inflammatory disease resulting from interactive immune, genetic, and environmental factors. Various, epidemiological studies have shown the association of genetic variants of cytokine genes with a predisposition to RHD. However, the results from different populations are inconsistent. Therefore, we carried out a meta- analysis of twenty-three published case-control studies and the results indicated that TGF-β1 +869 T/C (T vs. C: OR = 7.68, 95% CI = 1.62-36.50; TT + CT vs. CC OR = 1.83, 95%CI = 1.39-2.41), TGF-β1-509 (T vs. C: OR = 2.76, 95% CI = 1.33-5.75), TNF-α(AA vs. GG: OR = 4.93,95% CI = 2.83-8.58; A vs. G: OR = 2.15, 95% CI = 1.13-4.12) and IL-1β -511C/T (CC + CT vs. TT: OR = 1.35, 95%CI = 1.02-1.78; C vs. T: OR = 2.36, 95% CI = 1.66-3.37) were significantly associated with increased risk of RHD. On the other hand, IL-10(-1082)G/A polymorphism (GA vs. AA: OR = 0.91, 95% CI = 0.36-2.33; G vs. A: OR = 1.90, 95% CI = 0.58-6.22) and IL-6-174 G/C (CC + GC vs. GG: OR = 0.68, 95%CI = 0.32-1, C vs. G: OR = 1.14, 95% CI = 0.82-1.60) were not associated with modified RHD risk. The meta-analysis results were similar in Asians and non-Asians. Therefore, cytokine gene polymorphisms play important role in the genetic susceptibility of RHD in rheumatic fever patients.

Effect of genetic variant (rs11887534) in ABCG8 gene in coronary artery disease and response to atorvastatin therapy

BACKGROUND

ATP-binding cassette transporter ABCG8 plays an important role in excretion of cholesterol from liver. Common genetic polymorphisms in ABCG8 gene may genetically predispose an individual to coronary artery disease (CAD) along with response to atorvastatin therapy. Thus, we aimed to examine the role of ABCG8 D19H polymorphism (rs11887534) in susceptibility to CAD and its influence on atorvastatin response.

METHODOLOGY

The study included 213 CAD patients and 220 controls. Genotyping of ABCG8 D19H polymorphism was done by PCR-RFLP.

RESULTS

Our results showed that ABCG8 'H' allele was conferring significant risk for CAD in a dominant model (OR=2.54; p=0.014). This increased risk for CAD was more pronounced in males (OR=2.69; p=0.030). No correlation of ABCG8 genotypes with the risk factors (diabetes, hypertension and smoking) of CAD was observed. On atorvastatin treatment there was a significant decrease in the LDL-C levels (p=0.021). However, stepwise multiple regression analysis showed that this decease was not associated with ABCG8 genetic variant (p=0.845). Observed determinants of variation in interindividual response to atorvastatin therapy were pre-treatment LDL-C (p= 0.024) and TC (p=0.017).

CONCLUSION

Although the genetic variant 19H of ABCG8 confers risk for CAD in North Indian population, it is not associated with interindividual response to atorvastatin therapy.

No association of Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism in susceptibility to gallbladder cancer

Gallbladder carcinoma (GBC) is a leading cause of cancer deaths in north India. Evidence has highlighted the role of abnormal DNA methylation patterns on inappropriate gene expression in development and progression of various cancers. 5,10-Methylenetetrahydrofolate reductase (MTHFR) plays a major role in provision of methyl groups for DNA methylation. A C/T substitution in MTHFR at nucleotide 677 results in replacement of ala222-to-val in the N-terminal catalytic domain of protein, and causes considerable decrease in enzymatic activity. Thus, MTHFR C677T polymorphism may influence genetic susceptibility to GBC. The present study aimed to examine the role of C677T MTHFR polymorphism in conferring genetic susceptibility to GBC. The present study included 146 proven GBC patients and 210 healthy controls. Genotyping was done by PCR-RFLP method. The MTHFR C677T genotypes in control population were in Hardy-Weinberg equilibrium (p = ns). No statistically significant difference was observed in frequency of variant TT genotype in GBC patients in comparison to healthy controls (4.1% and 2.9%). Stratification of GBC patients on the basis of presence or absence of gallstones showed no significant association with the disease. Further, gender and age of onset of the disease did not show any significant association. In conclusion, the present study indicates that the genetic risk for GBC is not modulated by MTHFR C677T polymorphism.

Association of TERT-CLPTM1L and 8q24 Common Genetic Variants with Gallbladder Cancer Susceptibility and Prognosis in North Indian Population

Gallbladder carcinoma (GBC) is one of the common malignancy of the biliary tract. Several genome wide and candidate gene studies have reported associations between multiple cancer types and single-nucleotide polymorphisms on 5p15.33 and 8q24.21 loci. However, predisposition potential of these genetic variants has not been assessed in GBC. We performed the present study to assess the potential of five polymorphisms on 5p15.33 and one on 8q24.21 locus in GBC risk and treatment response in patients undergoing chemoradiotherapy. We extracted genomic DNA from peripheral blood and genotyped selected SNPs using TaqMan allelic discrimination assays in 523 GBC cases and 274 controls from the north-Indian population. Statistical tests were performed to assess the association of selected common genetic variants with gallbladder cancer susceptibility and prognosis. Binary logistic regression analysis showed significant association of TERT rs2736100C > A [OR(CI) = 0.690(0.515-0.924), p value = 0.013], CLPTM1L rs401681C > T [OR(CI) = 0.586(0.405-0.847), p value = 0.004], and CASC8 rs6983267G > T [OR(CI) = 1.629(1.215-2.186), p value = 0.001] with GBC risk. Further, using multivariate logistic regression, we observed that haplotype CLPTM1L Crs401681Crs31489 TERT Trs2853676Ars2736100 MIR4457 Grs4635969 [OR(CI) = 7.52 (1.79-31.52), p value = 0.0064] is significantly associated with poor treatment response. In survival analysis, Kaplan-Meier survival curves showed significantly poor survival and COX regression suggested significantly higher hazard ratio in TT genotype carriers of CASC8 rs6983267 [OR(CI) = 4.28(1. 07-17.10), p value = 0.040] as compared to major allele and heterozygous (GG+GT) genotypes in metastatic GBC cases. The study revealed that 5p15.33 and 8q24.21 genetic variants significantly influence GBC risk and treatment response in north-Indian population.

Association of microsomal epoxide hydrolase exon 3 Tyr113His and exon 4 His139Arg polymorphisms with gastric cancer in India

BACKGROUND

Microsomal epoxide hydrolase, an important phase II xenobiotic enzyme, exhibits polymorphisms at exon 3 (Tyr113His [T/C]) and exon 4 (His139Arg [A/G]), which modulate enzyme activity; this may affect susceptibility to cancers. We studied association between these polymorphisms and gastric cancer (GC).

METHODS

In a prospective study, 77 patients with GC, 50 with peptic ulcer, and 160 healthy controls (HC) were genotyped for exon 3 (PCR-RFLP followed by sequencing) and exon 4 (PCR-RFLP). Helicobacter pylori was considered to be present if two of three tests (histology, rapid urease test, and IgG antibody) were positive.

RESULTS

Tyr113His and His139Arg genotypes and haplotypes were comparable among groups. 113His carriers were commoner among H. pylori-negative patients with GC than HC (p-value = 0.019, odds ratio (OR) = 2.5, 95 % confidence interval (CI) = 1.2-5.4). Haplotype combination of exons 3 and 4 113Tyr-139Arg (TA) were associated with higher and reduced risk in patients with GC than HC in presence and absence of H. pylori (25 % vs. 11 %; p-value = 0.033, OR = 2.61, 95 % CI = 1.08-6.3 and 11.6 % vs. 28.7 %; p-value = 0.004, OR = 0.33, 95 % CI = 0.15-0.7, respectively).

CONCLUSIONS

Though 113Tyr-139Arg was associated with GC in presence of H. pylori, in its absence, it appeared to be protective. Exon 3, 113His, however, was associated with GC even in absence of H. pylori infection.

Relationship of MTHFR and NQO1 Pharmacogenetics and Chemotherapy Clinical Outcomes in Breast Cancer Patients

The study aimed at evaluating the influence of MTHFR 677C>T and NQO1 609C>T polymorphisms in toxicity and response to chemotherapy in breast cancer patients. These two genes are involved in the folate homeostasis and bioactivation of chemotherapeutic drugs, respectively. In this study, 243 patients treated with FEC/FAC/methotrexate chemotherapy regimen were recruited and followed up for toxicity (NCI-CTCAE ver. 3). While out of 243 patients, 115 patients who received neo-adjuvant chemotherapy (NACT) were followed for treatment response. Genetic analysis of MTHFR 677C>T and NQO1 609C>T was done by PCR-restriction fragment length polymorphism. We found significant association of variant genotype (TT) of NQO1 609C>T with grade 2-4 toxicity [OR 0.33 (0.13-0.88), P = 0.027] and with grade 2-4 anemia [OR 0.34 (0.12-0.95), P = 0.041]. However, no association of MTHFR 677C>T was seen with either response to NACT or drug-induced toxicity. The study provides useful information for prediction of clinical outcomes in breast cancer patients in terms of NQO1 609C>T by evaluating its association with chemotherapy-induced toxicity.

Association of Common Single Nucleotide Polymorphisms of Candidate Genes with Gallstone Disease: A Meta-Analysis

Numerous studies have investigated the relationship between various candidate gene polymorphisms and gallbladder stone disease (GSD) across ethnic populations; however, the results are often inconsistent. This meta-analysis aims to comprehensively evaluate the influence of common ABCG8 T400K, ABCG8 D19H, ABCG8 C54Y, ApoB100 EcoRI, ApoB100 XbaI, ApoE HhaI, CETP TaqI, CYP7A1 Bsa, LRPAP1 I/D and TNF-α A308G polymorphisms on the risk of gallbladder stone disease. 33 Full-text articles with 9250 cases and 12,029 healthy controls (total 21,279 subjects) were analyzed using the RevMan software (V5.1) and the Comprehensive Meta-analysis software (Version 2.0, BIOSTAT, Englewood, NJ) a Random-effects model was applied. Begg's funnel plots, Fail-safe number, Egger's regression intercept and Begg and Mazumdar rank correlation tests were performed for the potential publication bias and sensitivity analysis. The studies were also sub-grouped into European and non-European groups to find out role of ethnicity, if any, on GSD risk. Studies included in quantitative synthesis were ABCG8 T400K rs4148217 (cases/controls, n = 671/1416) (4 studies), ABCG8 D19H rs11887534 (n = 1633/2306) (8 studies), ABCG8 C54Y rs4148211 (n = 445/1194) (3 studies), ApoB100 EcoRI rs1042031 (n = 503/390) (4 studies), ApoB100 XbaI rs693 (n = 1214/1389) (9 studies), ApoE HhaI rs429358 (n = 1335/1482) (12 studies), CETP TaqI rs708272 (n = 1038/1025) (5 studies), CYP7A1 Bsa rs3808607 (n = 565/514) (3 studies), LRPAP1 I/D rs11267919 (n = 849/900) (3 studies), TNF-α A308G rs1800629 (n = 997/1413) (3 studies). The combined results displayed significant association of ABCG8 D19H (GC + CC) [OR with 95%CI = 2.2(1.7-2.8); p < 0.00001], ABCG8 Y54C (GA + GG) [OR with 95%CI = 0.65(0.5-0.9); p = 0.01]. APOB100 EcoRI (GG vs. AA) [OR with 95%CI = 0.51(0.3-0.9); p = 0.05], (GG vs. GA) [OR with 95%CI = 0.6(0.4-0.9); p = 0.04], (GA + AA) [OR with 95%CI = 0.6(0.4-0.9); p = 0.006]. APOB Xba I (X- vs. X+) [OR with 95%CI = 0.53(0.3-0.8); p = 0.006. APOE Hha I (E4/E4 vs. E3/E3) [OR with 95%CI = 3.5(1.1-14.9); p = 0.04] and LRPAP1 I/D (ID + II) [OR with 95%CI = 1.27(1.0-1.6); p = 0.03] with the GSD risk. It was found that ABCG D19H was significantly associated with GSD in both European and Non-European populations. While APOB XbaI and LRPAP1 I/D markers were associated with gallstone disease only in Non- European population. Additionally, APOE HhaI and APOB 100 ECoRI were found to be associated with GSD only in European population. The results of quantitative synthesis suggest that the ABCG8 D19H polymorphism was associated with the increased risk of GSD in both European and Non-European populations, APOE Hha I and LRPAP1 I/D polymorphisms were associated with the increased risk of GSD in European and Non-European population respectively. However, no association was found in ABCG8 T400K, CETP Taq1, CYP7A1 Bsa and TNF-A308G polymorphisms with Gallstone Disease.

Higher alleles of apolipoprotein B gene 3' VNTR: Risk for gallstone disease

Imbalance in cholesterol homeostasis may lead to gallstone disease. Apolipoprotein B is sole component of low-density lipoprotein and plays an important role in cholesterol metabolism. The present study was carried out to explore the association of APOB 3' VNTR, exon 26 XbaI and signal peptide insertion/ deletion polymorphisms with gallstone disease. 214 ultrasonographically proven gallstone patients and 322 healthy, age and sex matched controls were taken for the study. Genotyping was done using PCR followed by polyacrylamide gel electrophoresis for VNTR and insertion/ deletion analysis. For APOB XbaI polymorphism PCR product was digested with XbaI restriction enzyme, followed by agarose gel electrophoresis. All statistical analyses were done using SPSS v11.5. Higher repeat alleles of APOB 3' VNTR polymorphism were more frequent in gallstone patients than in controls. Alleles with more than 57 repeats were present only in patient group. Long (L) alleles with repeat higher than 49, were significantly higher (P=0.000; OR=3.705, 95% CI 2.577-5.326) and medium (M) alleles were lower (P=0.000; OR=0.406, 95% CI 0.304-0.542) in patients than in controls. To nullify the effect of gender, data was further stratified into male and female population. APOB 3' VNTR, L alleles were imposing risk and M alleles were protective in both male and female population. APOBXbaI and insertion/deletion polymorphisms were not found to be associated with the gallstone disease. Longer alleles of APOB 3' VNTR occur more frequently in gallstone patients, and may be an important risk factor for the development of gallstone disease. APOB XbaI and signal peptide insertion/deletion polymorphisms may not be contributing to the risk for gallstone disease.

Phosphodiesterase 4 D gene polymorphism in relation to intracranial and extracranial atherosclerosis in ischemic stroke

In ischemic stroke, extracranial MR angiography (ECMRA) is more frequently abnormal in Caucasians and intracranial (ICMRA) in Asians which may have a genetic basis. We report phosphodiesterase (PDE4D) gene polymorphism and its correlation with MRA findings in patients with ischemic stroke. Consecutive patients with MRI proven ischemic stroke undergoing MRA were included in this study. The severity of atherosclerotic stenosis on MRA was categorized into moderate 50%-80%, severe 80%-99%, and total occlusion 100% using NASCET criteria. The polymorphism in SNP 32, SNP 83 and SNP 87 of PDE4D gene was analyzed by PCR both in the patients and in 188 controls. Among the 148 patients, MRA was abnormal in 77% patients; ECMRA in 53.8%, ICMRA in 66% and both were abnormal in 42% patients. The frequency of CC genotype of PDE4D83 was significantly higher in the patients with ischemic stroke compared to controls (OR 3.38, 95% CI 1.61-7.11, P= 0.001). The frequency of TT genotype of PDE4D87 was significantly higher ICMRA abnormalities (20%) compared to normal ICMRA (2%). The genotype and allele frequency of PDE4D83 and PDE4D32 were not significantly related to MRA abnormalities. The role of PDE4D87 in atherosclerosis needs confirmation in larger studies.

Is IL-10-819C/T gene polymorphism modulating the risk of gallbladder disease in north Indian population?

BACKGROUND

Gallbladder carcinoma (GBC) is a highly aggressive neoplasm that arises in the background of gall stones and inflammation. Anti-inflammatory cytokine interleukin-10 (IL-10) gene polymorphisms have been associated with susceptibility to various inflammatory diseases and cancers.

AIM

of the study The aim of the present study was to investigate whether IL-10-819C/T polymorphism is associated with GBC susceptibility.

METHODS

The study subjects comprised 124 GBC patients, 135 patients with symptomatic gallstone disease, and 200 healthy subjects. Genomic DNA was extracted from blood leukocytes and IL-10-819C/T gene polymorphism was analyzed by polymerase chain reaction-restriction fragment length polymorphism.

RESULTS

Frequency distributions of IL-10-819C/T genotypes were similar in GBC, gallstone patients, and healthy subjects. However, after stratification on the basis of sex, in male GBC patients, the TT genotype of IL-10-819C/T polymorphism showed an approximately sevenfold risk (p value = 0.038; odds ratio = 6.58; 95% confidence interval = 1.11-39.11) in the presence of gall stones when compared with gallstone patients.

CONCLUSION

These results suggest that interplay of sex hormones and IL-10-819C/T polymorphism may lead to the susceptibility of gallstone-mediated gallbladder carcinogenesis.

Role of angiotensin II type I (AT1 A1166C) receptor polymorphism in susceptibility of left ventricular dysfunction

BACKGROUND

Left ventricular dysfunction (LVD) with subsequent congestive heart failure (CHF) constitutes the final common pathway for a host of cardiac disorders. The impaired LV function develops in response to an ischemic insult followed by a fall in cardiac output that leads to activation of renin-angiotensin-system (RAS). Angiotensin II type I receptor (AT1), which mediate the vasoconstrictive and salt-conserving actions of the RAS, represent interesting candidate genes for cardiovascular diseases. Therefore, we conducted an association study between single nucleotide polymorphism (SNP) in AT1 gene and LVD in CAD patients.

METHODS AND RESULTS

The present study recruited a total of 950 subjects including 720 angiography confirmed CAD patients and 230 healthy controls. Among 720 CAD patients, 229 with reduced left ventricle ejection fraction (LVEF≤45%) were categorized as LVD. The AT1 (A1166C, rs5186) polymorphism was determined by ARMS-PCR. Our results showed that the frequency of AT1 1166AC and CC genotypes were significantly higher in LVD patients in comparison to non-LVD (LVEF >45%) patients (p value = 0.003; OR = 1.81 and p value <0.001; OR = 4.33). Further analysis showed that AT1 A1166C polymorphism was significantly associated with LV end diastole (p-value = 0.031), end systole (p-value = 0.038) dimensions, and mean LVEF (p-value = 0.035). Moreover, on comparing the AT1 A1166C polymorphism in CAD patients with healthy controls, we did not find any association both at genotypic and allelic level (p value = 0.927; OR = 1.04 and p value = 0.219; OR = 0.83) respectively.

CONCLUSIONS

Our study suggests that AT1 A1166C polymorphism may play significant role in conferring genetic susceptibility of LVD.

Multi-analytic approach elucidates significant role of hormonal and hepatocanalicular transporter genetic variants in gallstone disease in North Indian population

OBJECTIVE

Cholesterol gallstone disease (CGD) is a multifactorial and multistep disease. Apart from female gender and increasing age being the documented non-modifiable risk factor for gallstones the pathobiological mechanisms underlying the phenotypic expression of CGD appear to be rather complex, and one or more variations in genes could play critical roles in the diverse pathways further progressing to cholesterol crystal formation. In the present study we performed genotyping score, Multifactor dimensionality reduction (MDR) and Classification and Regression Tree analysis (CART) to identify combinations of alleles among the hormonal, hepatocanalicular transporter and adipogenesis differentiation pathway genes in modifying the risk for CGD.

DESIGN

The present case-control study recruited total of 450 subjects, including 230 CGD patients and 220 controls. We analyzed common ESR1, ESR2, PGR, ADRB3, ADRA2A, ABCG8, SLCO1B1, PPARγ2, and SREBP2 gene polymorphisms to find out combinations of genetic variants contributing to CGD risk, using multi-analytical approaches (G-score, MDR, and CART).

RESULTS

Single locus analysis by logistic regression showed association of ESR1 IVS1-397C>T (rs2234693), IVS1-351A>G (rs9340799) PGR ins/del (rs1042838) ADRB3-190 T>C (rs4994) ABCG8 D19H (rs11887534), SLCO1B1 Exon4 C>A (rs11045819) and SREBP2 1784G>C (rs2228314) with CGD risk. However, the MDR and CART analysis revealed ESR1 IVS1-397C>T (rs2234693) ADRB3-190 T>C (rs4994) and ABCG8 D19H (rs11887534) polymorphisms as the best polymorphic signature for discriminating between cases and controls. The overall odds ratio for the applied multi-analytical approaches ranged from 4.33 to 10.05 showing an incremental risk for cholesterol crystal formation. In conclusion, our muti-analytical approach suggests that, ESR1, ADRB3, in addition to ABCG8 genetic variants confer significant risk for cholesterol gallstone disease.

Influence of IL-1β, STAT3 & 5 and TLR-5 gene polymorphisms on rheumatic heart disease susceptibility in north Indian population

BACKGROUND

Rheumatic heart disease (RHD) is the most serious complication of heart that comprises inflammatory reactions in heart valves. Many studies have demonstrated the contribution of host genetic factors in susceptibility to RHD and many cytokine gene variants have been linked with susceptibility to RHD. We sought to determine the role of genetic variants in IL-1β, STAT3, STAT5B and TLR5 genes in conferring risk of RHD in two cohorts of RHD patients.

METHODS

The study included 400 echocardiography confirmed RHD patients and 300 controls from North Indian Population. We categorized RHD patients into two sub-groups based on involvement of heart valves, mitral valve lesion alone (MVL), and combined valve lesions including mitral valve (CVL). Genotyping for all the polymorphisms was done using TaqMan /PCR-RFLP methods.

RESULTS

Our results showed that the genotypic frequencies of IL-1β, STAT3, STAT5B andTLR5 genes polymorphisms were significantly associated with RHD risk. To validate our results, we performed a replication study in additional 200 cases with similar clinical characteristics and results again confirmed consistent findings with RHD risk. In subgroup analysis, STAT3 polymorphism remained significant with MVL in RHD patients.

CONCLUSION

IL-1β, STAT3, STAT5B and TLR5 genes polymorphism may be useful markers for the identification of individuals with high risk of RHD in the susceptible population.