Pravin Kesarwani

Anti- and proinflammatory cytokine gene polymorphism and genetic predisposition: association with smoking, tumor stage and grade, and bacillus Calmette-Guérin immunotherapy in bladder cancer

Cytokines mediate many immune and inflammatory responses contributing to tumorigenesis. The present study evaluated polymorphisms of IL4, IL6, and TNF (previously TNFA) genes influencing risk in development of transitional cell carcinoma of bladder and recurrence after bacillus Calmette-Guérin (BCG) immunotherapy. The study included 136 unrelated histopathologically confirmed cases and 200 population-based controls. Genomic DNA was extracted from peripheral leukocytes and genotyped for polymorphism in IL4 intron 3, with point mutations identified by amplification refractory mutation system polymerase chain reaction (ARMS-PCR) in IL6-174 G/C and by PCR-restriction fragment length polymorphism analysis in TNF-308 G/A. The IL6 variant C/C exhibited significant association with bladder cancer risk (odds ratio OR = 2.811, P = 0.004), but IL4 and TNF genetic variants did not. Significant association was observed for IL4 (B1/B2+B2/B2) with high-grade or late-stage tumor for TaG3+T1 and T2+ (OR = 5.950, and 6.342 respectively) and with smoking (P = 0.004, OR = 4.202). Low recurrence risk was observed in BCG-treated patients carrying C/C genotype of IL6 (hazard ratio = 0.298, P = 0.03), and also higher recurrence-free survival (log rank P = 0.021). TNF and IL4 demonstrated no association of bladder cancer risk and BCG therapy. The low-producing variant C/C of IL6 may be a risk factor for bladder cancer, whereas high-producing genotypes of IL4 (B1/B2+B2/B2) may predispose to higher risk in patients with high-grade or late-stage tumor and smoking habits. The low-producing C/C IL6 genotype, which favors Th1 response, may be a beneficial prognostic indicator for treatment and survival of BCG-treated patients.

XRCC1 codon 399 mutant allele: A risk factor for recurrence of urothelial bladder carcinoma in patients on BCG immunotherapy

XRCC1 protein plays crucial role in base excision repair (BER) by acting as a scaffold for other BER enzymes. Variants in XRCC1 gene might alter protein structure/function or create alternatively spliced protein influencing BER efficiency and affect individual susceptibility/recurrence to urinary bladder cancer (BC). We tested whether polymorphisms in XRCC1 gene were associated with BC risk and further to substantiate risk of recurrence after Bacillus Calmette-Guerin (BCG) immunotherapy. Genotyping for three polymorphic sites of XRCC1 gene at codon Arg194Trp (PvuII), Arg280His (RsaI) and, Arg399Gln (MspI) in 140 BC cases and 190 controls by PCR-RFLP method was done. We observed significant association in heterozygous genotype (GA) of codon 280 and 399 with BC risk (OR=1.96, p=0.021 and OR = 1.81, p=0.021, respectively), however no association was seen for variant AA genotype. A trend of increased risk with high stage and grade in patients with codon 194 variant genotypes (CT+TT) was observed. Haplotype analysis showed that individuals with haplotype 194C-280G-399A were at >3-fold higher risk for BC (OR=3.48, p=0.01). The A/A genotype of codon 399 was associated with high risk for recurrence in BCG treated patients (HR=5.05, P=0.01) thus, showing reduced recurrence free survival (AA/GG=12/60months; log rank P=0.004). The study suggested no association of variant genotypes with the susceptibility to BC. Haplotype analysis however, revealed that XRCC1 399 A allele may have a major role as patients with haplotype 194C-280G-399A carrying variant allele of 399 were at higher risk. Running Title XRCC1 gene polymorphism and risk of recurrence after BCG immunotherapy

Association of tumour necrosis factor‐α gene (T‐1031C, C‐863A, and C‐857T) polymorphisms with bladder cancer susceptibility and outcome after bacille Calmette‐Guérin immunotherapy

To investigate the association of tumour necrosis factor‐α gene (TNF‐α) polymorphisms T‐1031C, C‐863A, and C‐857T with bladder cancer risk and recurrence after bacille Calmette‐Guérin (BCG) immunotherapy, as TNF‐α regulates inflammatory process influencing bladder cancer susceptibility and outcome of BCG immunotherapy.

Association between −174 G/C Promoter Polymorphism of the Interleukin-6 Gene and Progression of Prostate Cancer in North Indian Population

The cellular alterations that give rise to cancer initiate changes in cytokine expression. Though IL-6 is known to play a major role in proliferation of tumor cells, IL-4 upregulates androgen receptors and prostate-specific antigen (PSA). The present study was undertaken to evaluate the association of IL-4 and IL-6 gene polymorphisms for the susceptibility to prostate cancer (PCa) risk. Our study included 200 controls and 200 histologically confirmed cases of PCa. Polymorphisms in IL-4 (intron 3, by VNTR analysis) and IL-6 (-174 G/C, by amplification refractory mutation system, i.e., ARMS-PCR) were genotyped in all the subjects. There was no significant association of IL-4 and IL-6 gene polymorphisms with the risk of PCa. Nevertheless, twofold risk with progression to bone metastasis (odds ratio = 2.09; 95% confidence interval = 1.16-3.75; p = 0.014) in PCa patients was observed. No association with other confounding factors such as PSA level, Gleason score, and lifestyle-associated risk factors like tobacco chewing and cigarette smoking was seen. Our study suggests that an IL-6 gene variant may be associated with prostate progression and bone metastasis.

Influence of caspases 8 and 9 gene promoter polymorphism on prostate cancer susceptibility and early development of hormone refractory prostate cancer

What’s known on the subject? and What does the study add?

Polymorphisms in Tumor Necrosis Factor-A Gene and Prostate Cancer Risk in North Indian Cohort

PURPOSE The proinflammatory cytokine tumor necrosis factor-alpha has an important role in the pathogenesis of prostate cancer. Single nucleotide polymorphisms in the promoter region of the TNF-A gene alter tumor necrosis factor-alpha transcription. Thus, we studied the association of 4 SNPs in the promoter region of TNF-A gene, including -1031T>C, -863C>A, -857 C>T and -308 G>A, in a North Indian cohort of patients with prostate cancer. MATERIALS AND METHODS The study involved 453 subjects. All 197 case and 256 control samples were genotyped for the 4 promoter polymorphisms in the TNF-A gene using allele specific polymerase chain reaction and polymerase chain reaction-restriction fragment length polymorphism. RESULTS Results showed an increased risk of prostate cancer for the TNF-A -1031 CC genotype (OR 2.01, p = 0.03). No significant association was observed for the TNF-A -863 C>A, TNF-A -857 C>T or -308 G>A polymorphisms. Haplotype analysis revealed that TNF-A -1031C-863C-857T-308G was significantly associated with prostate cancer risk (OR 2.22, p = 0.013). Moreover, the TNF-A -1031 C and -857 T alleles were associated with higher tumor grade and an increased risk of tumor progression and metastasis. CONCLUSIONS These results show that TNF-A polymorphisms have an important role in prostate cancer pathogenesis. Results are in line with findings in other studies from the West and to our knowledge for the first time from India indicating the involvement of immune system genes in prostate cancer pathogenesis.

Role of Tumor Necrosis Factor-Alpha (C-863A) Polymorphism in Pathogenesis of Inflammatory Bowel Disease in Northern India

ObjectiveInflammatory bowel diseases (IBDs), namely ulcerative colitis (UC) and Crohn’s disease (CD), are characterized by chronic and idiopathic inflammatory conditions of gastrointestinal tract that are immunologically mediated. Single nucleotide polymorphisms in cytokine genes have been reported to modulate inflammation. Therefore, we analyzed the association of pro/anti-inflammatory cytokine genes polymorphism with IBD susceptibility.MethodsGenotyping of interleukin (IL)-4 repeat polymorphism in intron-3, IL-10 (G-1082A and C-819T), and tumor necrosis factor-alpha (TNF-A) (−1031 T>C, −863 C>A, and −857 C>T) was performed in 153 patients with IBD and in 207 controls.ResultsTNF-A −863 AA genotype was associated with enhanced IBD susceptibility (odds ratio (OR), 4.82; 95% confidence interval (CI), 2.60–8.96), more so for UC (OR, 5.79; 95% CI, 2.99–11.21), Crohn’s disease [CD] (OR, 3.13; 95% CI, 1.16–8.47). TNF-A T/C/T (OR, 4.40; 95% CI, 1.64–11.81) and C/A/C (OR, 4.15; 95% CI, 2.48–6.96) haplotypes were associated with increased IBD risk. The frequency of IL-4, B2 carrier (B1/B2 + B2/B2) was significantly lower in left-sided UC (17.1%) than proctosigmoiditis (47.6%); p, 0.016. In contrast, TNF-A −863 AA genotype frequency was much higher in pancolitis (45.5) than in proctosigmoiditis (14.2); p, 0.037. Variant genotypes of IL-4 (B1/B2 + B2/B2) were absent in colonic type CD. IL-10 polymorphisms did not demonstrate any association with IBD. None of the polymorphisms were associated with steroid treatment and surgery.ConclusionThe present study depicts that high-producing genotype of TNF-A (−863 AA) was associated with increased risk of IBD more so with UC. Similarly, combined effect of TNF-A polymorphisms in haplotype analysis demonstrated additively increased risk of IBD.

Influence of genetic polymorphisms in GSTM1, GSTM3, GSTT1 and GSTP1 on allograft outcome in renal transplant recipients

Abstract:  Introduction:  Glutathione S‐transferases (GSTs) are important in protection against xenobiotic compounds and toxicity caused by immunosuppressants in renal transplant recipients. In the present study we hypothesize that genetic variability in GSTM1, GSTM3, GSTP1 and GSTT1 genes may be associated with allograft outcome.

Interleukin 8 −251T>A and Interferon gamma +874A>T polymorphism: Potential predictors of allograft outcome in renal transplant recipients from north India

BACKGROUND Episodes of acute rejection represent an important risk factor for the development of chronic allograft nephropathy. We explored whether certain cytokine gene polymorphisms in renal transplant recipients may be useful markers for susceptibility to allograft rejection. Interleukin 8 (IL8) -251 T>A and interferon gamma (IFNG) +874A>T gene polymorphisms were correlated with allograft outcome in renal transplant recipients. METHODS Genotyping was done by amplification refractory mutational system-polymerase chain reaction (ARMS-PCR) in 264 healthy controls and 296 renal transplant recipients categorized into 235 non-rejecters and 61 rejecters. RESULTS IL8 -251AA genotype was associated with 2.7-folds increased risk for allograft rejection in recipients experiencing rejection episodes as compared to non-rejecters (OR=2.70, P=0.032). Cox proportional analysis revealed >2-folds increased susceptibility for allograft rejection (HR=2.38, P=0.010) in IL8 -251AA recipients. Kaplan-Meier analysis also demonstrated lower mean time to first rejection episode for IL8 -251AA recipients (23 months) as compared to TT recipients (30 months) (log rank P=0.022). No association of IFNG +874A>T was observed with allograft rejection, however, an increasing trend towards immunosuppressant toxicity was observed in patients with +874TT genotype at one month post transplantation. CONCLUSION Thus, IL8 -251AA genotype may serve as potential predictor of allograft outcome in our North Indian cohort of renal transplant recipients.

GSTM1, GSTM3 and GSTT1 Gene Variants and Risk of Benign Prostate Hyperplasia in North India

Glutathione S-transferases (GSTs) play an important role in detoxification of various toxic compounds like carcinogens in cigarette smoke and tobacco by conjugating to toxic compounds and inactivating their hazardous effect. Variation in Glutathione S-Transferases (GSTs) genes may alter the catalytic efficiency of GST isoenzymes leading to potential increase in cancer susceptibility due to various carcinogens. We therefore, investigated association of GSTM1, GSTM3 and GSTT1 variants with susceptibility to benign prostate hyperplasia (BPH) and cigarette, tobacco chewing and alcohol consumption as confounding factors in 141 BPH and 184 healthy controls. Results showed increased risk for BPH susceptibility in patients with GSTM1 null genotype (OR-2.03, p = 0.013) and smoking (OR-3.12, p = 0.028), tobacco chewing (OR-2.54, p = 0.039) and alcohol habits (OR-3.39, p = 0.010). Null genotype of GSTM1 with cigarette, tobacco and alcohol habits predisposed increased risk for BPH.