Vibha Singh

Association of IL-12, IL-18 variants and serum IL-18 with bladder cancer susceptibility in North Indian population.

IL-12 and IL-18 are immunomodulatory cytokines that play important roles in host immune response against cancers. Variation in DNA sequence in gene promoter may lead to altered IL-18 production and/or activity, and hence can modulate an individuals susceptibility to BC. To test this hypothesis, we investigated the relationship of IL-18 gene promoter -137 G/C and -607C/A polymorphisms and IL12 (-16974) A/C with the risk of BC in North Indian population. Polymorphisms in IL-18 and IL-12 genes were analyzed in 200 BC patients and 200 age, ethnicity and sex-matched controls, using restriction fragment length polymorphism-polymerase chain reaction (PCR-RFLP) and amplification refractory mutation specific-polymerase chain reaction (ARMS) method. The concentrations of IL-18 in serum were determined by ELISA. Significant association was observed with IL18 (-137) G/C heterozygous genotype (GC) with 1.96 folds risk of BC as well at C allele carrier and variant C allele having 2 fold and 1.6 fold risk for BC respectively. IL18 (-607) C/A, heterozygous CA genotype also showed a high risk (OR=1.59) for BC. While IL12 (-16974) A/C heterozygote genotype and C allele carrier demonstrated reduced risk of BC. Hetero genotype of IL18 (-137) G/C was associated with risk of recurrence (HR=2.35) in superficial BC patients receiving BCG treatment thus showing least survival. The distributions of IL-18 gene haplotypes were not significantly different between patients and controls. Serum IL-18 levels were significantly higher in BC patients than in the healthy subjects (p=0.025). Serum IL-18 levels was also significantly associated with IL18 (-137) G/C in heterozygous genotype (GC) (p=0.048). Our results suggest that IL-18 gene polymorphism contributes to bladder cancer risk whereas IL-12 is protective. A relation between IL18 (-137) G/C in heterozygous genotype with elevated IL-18 serum level and bladder cancer risk has been registered in the present study.

Single-nucleotide polymorphisms in genes encoding toll-like receptor -2, -3, -4, and -9 in a case-control study with bladder cancer susceptibility in a North Indian population.

BACKGROUND AND AIMS Impairment of the immune system may contribute to the risk for having cancer as Toll-like receptors are important for innate immunity. We examined the association between candidate disease-susceptibility polymorphisms in the single nucleotide polymorphism (SNPs) like TLR2 (-196 to-174del), TLR3 (C1377T), TLR4 (Thr399Ile) and TLR9 (G2848A) genes in patients with bladder cancer in a North Indian population. METHODS SNPs were comprised of TLR2 (-196 to -174 Del), TLR3(C1377T), TLR4 (Thr399Ile) and TLR9 (G2848A) genes. Allelic and genotypic frequencies of these TLRs SNP from histopathologically confirmed patients of bladder cancer (n = 200) and unrelated healthy controls of similar ethnicity (n = 200) were genotyped by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) analysis. RESULTS In TLR2 I/D gene polymorphism, the combination of ID+DD showed a significant 3-fold increased risk (p = 0.001). TLR2 with heterozygous genotype ID showed a 3-fold risk and combination of heterozygous and variant genotype (ID+DD) also showed a 5-fold risk with tumor stage/grade of patients with bladder cancer. The other genotypes of TLR3, 4 and 9 did not exhibit any significant association with bladder cancer risk. CONCLUSIONS Our results suggested the involvement of TLR2 (-196 to-174 del) in bladder cancer susceptibility; however, TLR3, 4 and 9 genes were not associated with risk of bladder cancer, implicating that polymorphisms in these tested TLRs genes are not likely to be associated with increased risk for developing bladder cancer. Functional studies in ethnically diverse populations may provide a more comprehensive involvement of innate immunity in identifying the disease-associated variants for the etiology of bladder cancer.

Association of death receptor 4, Caspase 3 and 5 gene polymorphism with increased risk to bladder cancer in North Indians

PURPOSE Perturbed apoptosis due to missense alterations in candidate tumor suppressor gene Death receptor 4 (DR4) and in caspases (Casp) lead to deregulated cell proliferation and cancer predisposition. Some data indicate that normal variations within the sequence of apoptotic genes may lead to suboptimal apoptotic capacity and therefore increased cancer risk. To test our proposal we examined whether six single nucleotide polymorphisms (SNPs) of the DR4 and Casp3, 5 genes contrive the risk of bladder cancer (BC) in a North Indian population. MATERIALS AND METHODS Genotyping was performed in 200 BC patients and 225 controls by Allele-specific PCR and by polymerase chain reaction-restriction fragment length polymorphism. RESULTS In DR4 Arg141His, BC patients having AA genotype (p = 0.036; OR = 2.51. In Casp5Leu13Phe G > C, significant association was observed with GC (p = 0.025; OR = 1.78) and also in GC + CC (p = 0.026; OR = 1.68). C allele carriers in Casp5Ala90Thr T > C showed low risk of BC (p = 0.036; OR = 0.83). While in Casp3 G > A, AG (p = 0.003; OR = 2.11), GG (p = 0.050; OR = 2.18), G allele (p < 0.001; OR = 1.85) and its carrier AG + GG (p = 0.001; OR = 2.12) have shown significant BC risk. Significant association between DR4 Ala228Glu polymorphism and smoking was observed in BC risk. Haplotype analysis demonstrated that DR4 (Thr209Arg-Arg141His-Ala228Glu) C-G-C is associated with 1.8 folds (OR = 1.85; p = 0.033) risk. GG genotype of Casp3 G > A polymorphism showed increased risk of recurrence (p = 0.009; HR = 5.20). CONCLUSION This study provided new support for the association of DR4 and Casp3, 5 in BC development, the tumorigenic effect of which was observed to be more enhanced in case of smoking exposure.

Association of Common Variants of Vascular Endothelial Growth Factor and Interleukin-18 Genes with Allograft Survival in Renal Transplant Recipients of North India

Increased vascular endothelial growth factor (VEGF) production promotes enhanced endothelial permeability, enhanced leukocyte migration into the allograft, thereby leading to a clinically recognized rejection episode. Interleukin-18 (IL-18), a potent proinflammatory cytokine, may also be involved in mechanisms of kidney allograft rejection. The present study was, therefore, undertaken to investigate the association of functional polymorphisms in VEGF (2578C>A, 1154A>G) and IL-18 (607C>A, 137G>C) genes with risk of allograft rejection in renal transplant recipients of North India. Two hundred renal transplant recipients, 150 matched recipients-donors, and 200 unrelated healthy individuals were genotyped by amplification refractory mutation specific polymerase chain reaction and by polymerase chain reaction-restriction fragment length polymorphism. Variant allele VEGF 1154A>G (p = 0.56; odds ratio [OR] = 1.32) and variant allele (p = 0.004, OR = 1.54) and variant genotype (p = 0.007, OR = 3.26) of IL-18 607C>A, GC of IL-18 137G>C (p = 0.043, OR = 0.63) were significantly different in healthy individuals as compared with the patients with renal transplant. When 114 nonrejectors were compared with 36 rejectors (150 recipients) for association with allograft rejection, significant association was observed in heterozygous genotype of VEGF 2578C>A (p = 0.033), VEGF 1154A>G (p = 0.024). In IL-18 137G>C, CC genotype, C allele showed protective association with allograft rejection. Kaplan-Meier analysis indicated a higher mean time for first rejection episode in CA genotype carriers (31 months) as compared with AA (29 months) for VEGF 2578C>A (log p = 0.035). In VEGF, the haplotypes A-A and A-G (2578-1154) were associated with reduced risk and in IL-18 607A-137G, they were associated with high risk for allograft rejection. This observation suggests these polymorphisms are an ideal marker for prediction of pretransplant allograft outcome.

Do polymorphisms in XRCC4 influence prostate cancer susceptibility in North Indian population

Objective: XRCC4 play a key role in nonhomologous end-joining repair pathway. Alterations in DNA repair gene have been shown to reduce DNA repair capacity thereby inflicting carcinogenesis. Methods: In a hospital-based case-control study, 192 prostate cancer (PCa) and 224 healthy controls. They were genotyped for XRCC4 G-1394T (rs6869366), intron 3 (rs28360071) intron 7 (rs28360317) and intron 7 (rs1805377), polymorphisms using polymerase chain reaction–restriction fragment length polymorphism. Result: Carriers of GG genotype of rs6869366 were at reduced risk. Del/Del of rs28360071 and 28360317 demonstrated increased risk. The haplotype analysis was observed to be associated with a significant increase in PCa risk. Combined genotype of rs6869366, rs28360071 and rs1805377 have shown significant risk with high Gleason grade. Conclusion: Our results suggested that the variant genotype of XRCC4 rs28360071 and rs28360317 and haplotype analysis may be associated with PCa risk.

Role of p53 gene polymorphism and bladder cancer predisposition in northern India

p53 is a major orchestrator of cellular response to a broad array of stress types by regulating apoptosis, cell cycle arrest, etc. A few polymorphic sites, one at codon72 of exon4, intron3 16bpdel/ins, intron6G>A have been studied with regard to Bladder cancer (BC) risk in North Indians. Genotypes were assessed in hospital-based case-control study comprising of 200BC cases, 265healthy controls. After extraction of genomic DNA from blood, genotyping was done using PCR Restriction Fragment Length Polymorphism. Individuals with p53R72P G>C, CC genotype demonstrated marginally reduced risk of BC (p=0.053, OR=0.29, 95% 16bp-ins/del.

Replicative study of GWAS TP63C/T, TERTC/T, and SLC14A1C/T with susceptibility to bladder cancer in North Indians.

OBJECTIVE Genome-wide association studies have confirmed association of TP63C/T rs710521, TERTC/T rs2736098, and SLC14A1C/T rs17674580 gene variants with susceptibility to bladder cancer (BC) in European and White population. However, the risk conferred for BC for above gene variants in North Indians is unknown. We therefore, studied the association of TP63C/T, TERTC/T, and SLC14A1C/T single nucleotide polymorphisms (SNPs) with a risk of BC susceptibility in North Indian cohort. MATERIAL AND METHODS In histologically confirmed 225 BC cases and 240 healthy controls, 3 SNPs were genotyped by real-time polymerase chain reaction. To evaluate the SNP effects on BC susceptibility, odds ratio (OR) and CI 95% were calculated. RESULTS In case of TP63C/T, the variant genotype (TT) showed significant reduced risk for BC (P = 0.045, OR = 0.53). Combining heterozygous and variant genotypes also demonstrated reduced risk for BC (P< 0.001, OR = 0.54). In case of TERTC/T, heterozygous genotype (CT) as well as variant genotype (TT) showed significant risk for BC susceptibility (P = 0.031, OR = 1.77 and P = 0.004, OR = 2.78, respectively) along with T allelic level (P<0.001, OR = 4.19). Furthermore, in case of SLC14A1C/T gene polymorphism, the variant genotype (TT) showed significant high risk for BC susceptibility (P = 0.006; OR = 3.01) along with variant T allelic level (P = 0.003, OR = 1.52). Interestingly, smoking was also found to modulate risks for BC in case of TERT and SLC14A1 variant genotype (TT). Further clinical confounding factor, namely, tumor grade/stage level of cases, supports the genotypic data with TERT and SLC14A1 showing a risk for BC susceptibility. CONCLUSION Our results suggested that polymorphism in TERTC/T and SLC14A1C/T confirmed high risk for BC in North Indian population. However, TP63C/T showed reduced risk of BC susceptibility. More replicate studies with large sample size and diverse ethnicity are required to validate these observations.

Association studies of Toll-like receptor gene polymorphisms with allograft survival in renal transplant recipients of North India

Srivastava P, Singh A, Kesarwani P, Jaiswal PK, Singh V, Mittal RD. Association studies of Toll‐like receptor gene polymorphisms with allograft survival in renal transplant recipients of North India.

Polymorphism at P21 codon 31 and dinucleotide polymorphism of P73 gene and susceptibility to bladder cancer in individuals from North India.

BACKGROUND AND AIM: p73, a novel P53 homolog and plays an important role in modulating cell cycle control, apoptosis and cell growth while P21, functions to negatively control the cell cycle. P53 up regulates p21 expression in response to deoxyribonucleic acid damage leading to cell cycle arrest at G1 checkpoint. In the present study, we are targeting p21 codon 31 and p73 gene variants of G4C14-to-A4T14 (Exon 2) polymorphism for bladder cancer (BC) risk in North Indians. MATERIALS AND METHODS: The above gene variants of P21 and P73 were assessed in the case-control study comprising of 200 BC cases and 200 healthy controls of the same age, gender and similar ethnicity. Genotyping was performed by polymerase chain reaction (PCR) restriction fragment length polymorphism method and PCR-based confronting two-pair primers (PCR with CTPP). RESULTS: The variant genotype of p73Exon 2 polymorphism showed significant risk for BC (p = 0.014). While combining with heterozygous genotype, variant genotype of p73Exon2 showed a significant association with BC risk (p = 0.010). While in case of p21 codon31 showed no significant association for BC risk at genotypic level. Significant association between p73Exon2 polymorphism and smoking was observed for BC risk. Furthermore, gene combination analysis revealed that AT/AT-Ser/Ser is associated with risk for BC. Variant genotype of P73Exon2 was associated with reduced risk of recurrence (p = 0.039) in superficial BC patients receiving Bacillus Calmette-Guerin treatment thus showing least survival (log rank = 0.029). CONCLUSION: Our study provided evidence that the p73 G4C14 > A4T14 (Exon2) polymorphisms were associated with higher risk of BC in North Indian population.

Impact of chemokines CCR5∆32, CXCL12G801A, and CXCR2C1208T on bladder cancer susceptibility in north Indian population

Chemokines are small inducible pro-inflammatory cytokines. In the present study, we tested association of chemokine single nucleotide polymorphisms (SNPs) viz., CCR5∆32, CXCL12G801A and CXCR2C1208T genes in bladder cancer (BC) patients and normal healthy controls of north Indians. Genotyping of the above SNPs were done in 200 BC cases and 200 healthy controls, using RFLP and amplification refractory mutation system–polymerase chain reaction methodology. A significant association was found in CXCL12G801A with BC risk. In case of CXCL12G801A polymorphism, the heterozygous (GA) genotype showed significantly high risk (p < 0.001, odds ratio (OR) = 2.72), whereas A allele carrier (GA + AA) also showed risk with BC (p < 0.001, OR = 2.44). In CXCR2C1208T polymorphism, the variant genotype (TT) showed significant risk for BC (p = 0.028, OR = 1.58). The variant allele (T) of CXCR2C1208T polymorphism was found to be associated with BC risk (p = 0.003, OR = 1.29). Interestingly, smoking was also found to modulate 1.16-fold risks for BC in case of CXCR2C1208T, variant genotype (TT). Upon analyzing the gene–gene interaction between CXCR2C1208T and CXCL12G801A, the combination CT-GA showed 4-fold risk for BC (p = 0.009). Our results indicated that polymorphism in CXCR2C1208T and CXCL12G801A showed high risk for BC in north Indian population. However, CCR5∆32 exhibited no association. Study with large sample size and diverse ethnicity are required to validate these observations.