Parmeet Kaur Manchanda

Association of interleukin (IL)-4 intron-3 and IL-6 −174 G/C gene polymorphism with susceptibility to end-stage renal disease

Earlier studies suggest that end-stage renal disease (ESRD) is associated with inflammatory state and have become a major cause of morbidity and mortality worldwide. This study speculated the role of interleukins (IL)-2, -4, and -6 cytokines gene polymorphism with risk of susceptibility to ESRD. Polymorphism in IL-2 (−330 T/G, polymerase chain reaction [PCR]-restriction fragment length polymorphism), IL-4 (intron-3, variable number of tandem repeat, variable number tandem repeats analysis), and IL-6 (-174 G/C, amplification refractory mutation system, i.e. ARMS-PCR) were genotyped in 193 ESRD patients and 180 controls. Significant difference was observed in genotype frequencies of IL-4 and IL-6 between ESRD patients and control group (pu2009<u20090.001 and pu2009=u20090.032, respectively). Patients had higher frequency of homozygous B2B2 genotype (IL-4) than controls (62.7% vs 46.7) and GG genotype of IL-6 (73.1% vs 60.6%). The genotypic frequencies of IL-2 were comparable in patients and controls (pu2009=u20090.102). Significant association of IL-4 was also observed in patients with glomerulonephritis (pu2009=u20090.001). Combination of low IL-4 and high IL-6 genotypes were significantly associated with ESRD showing the highest risk, i.e. >threefolds risk (odds ratio=3.48, 95%CI=1.88–6.42; pu2009<u20090.001) among the four possible combinations taking high IL-4 and low IL-6 as reference. Our study suggests that polymorphism in IL-4 and IL-6 may be associated with susceptibility to ESRD. Further, combined analysis implicated a higher risk in ESRD patients with low IL-4 and high IL-6 producing genotypes. This study provided the basis for defined anti-inflammatory approaches to limit renal disease progression.

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.

Analysis of cytokine gene polymorphisms in recipient’s matched with living donors on acute rejection after renal transplantation

Despite advances in immunosuppressive therapy in last few years, allograft rejection still remains the concern for kidney graft failure. Cytokines are key mediators in the induction and effector phases of all immune and inflammatory responses. They are not allospecific so both recipient as well as donor cells may be subjected to cytokine changes. We sought to ascertain whether IL-1B −511, IL-1Bxa0+3954, TNF-A −308, TGF-B Codon 10 and 25, IL-2 −330, IL-6 −174, IL-10 −1082, IL-10 −819 (SNPs), IL-1RN, IL-4 (VNTR) and TGF-B C-del (deletion) genes in two hundred subjects including recipients and their live matched donors influence renal allograft outcome. Screening was performed using PCR-RFLP and amplification refractory mutation system (ARMS-PCR). The risk for rejection appeared significant amongst recipients for pro-inflammatory cytokines IL-1B +xa03954 (Pxa0=xa00.045) and TNF-A −308 (0.031). No association of cytokine gene variants with rejection was observed in donors group. Further evaluating combinational effect of TNF-A (−308), IL-4 and IL-10 (−819) genes with the risk of allograft rejection showed no additive influence. Haplotype analysis between IL-1 gene cluster, TGF-B Codon 10 and 25 and IL-10 −1082 and −819 revealed that haplotypes of IL-1 gene 240-T–C, 410-T–C and 410-T–T showed very high risk among the recipients (>16, >5 and >12 folds risk respectively) when compared to donors. Interestingly, all these three haplotypes contained the variant allele T* of IL-B −511. In conclusion, our results suggest that high producing genotypes of pro-inflammatory cytokine genes in recipients have risk for allograft rejection. Lack of association in donors may be suggestive of having no conspicuous role in allograft outcome. Further analysis of diversity in haplotype variations in large populations could conceivably provide the basis for defined approaches to limit the rejections.

Implications of XRCC1, XPD and APE1 gene polymorphism in North Indian population: a comparative approach in different ethnic groups worldwide.

Identifying risk factors for human cancers should consider combinations of genetic variations and environmental exposures. Several polymorphisms in DNA repair genes have impact on repair and cancer susceptibility. We focused on X-ray repair cross-complementing group 1 (XRCC1), Xeroderma pigmentosum D (XPD) and apurinic/apyrimidinic endonuclease (APE1) as these are most extensively studied in cancer. Present study was conducted to determine distribution of XRCC1 C26304T, G27466A, G23591A, APE1 T2197G and XPD A35931C gene polymorphisms in North Indian population and compare with different populations globally. PCR-based analysis was conducted in 209 normal healthy individuals of similar ethnicity. Allelic frequencies in wild type of XRCC1 C26304T were 91.1% C(Arg); G27466A 62.9% G(Arg); G23591A 60.3% G(Arg); APE1 T2197G 75.1% T(Asp) and XPD A35931C 71.8% A(Lys). The variant allele frequency were 8.9% T(Trp) in XRCC1 C26304T; 37.1% A(His) in G27466A; 39.7% A(Gln) in G23591A; 24.9% G(Glu) in APE1 and 28.2% C(Gln) in XPD respectively. We further compared frequency distribution for these genes with various published studies in different ethnicity. Our results suggest that frequency in these DNA repair genes exhibit distinctive pattern in India that could be attributed to ethnicity variation. This could assist in high-risk screening of humans exposed to environmental carcinogens and cancer predisposition in different ethnic groups.

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

Abstract:u2002 Introduction:u2002 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.

POLYMORPHISMS IN THE VITAMIN D RECEPTOR AND THE ANDROGEN RECEPTOR GENE ASSOCIATED WITH THE RISK OF UROLITHIASIS

Transcriptional activity of the vitamin D receptor (VDR) gene is regulated by androgen receptor (AR) gene and both are associated with renal stone formation. We examined gene polymorphisms of VDR (PCR-RFLP) and AR (GeneScan analysis) in 125 stone formers and 150 controls from north India. Genotype Ff of Fok-I and Tt of Taq-I demonstrated significantly higher risk (P<0.001, OR=3.559 and P=0.019, 1.830 respectively). Variant f allele exhibited 1.7-folds higher risk. Ff of Fok-I and Aa of Apa-I gene polymorphism showed higher risk in males only. Mean CAG repeat was significantly higher in hypercalciuric patients as compared to normocalciuric (mean=21.62 ± 3.384 vs. 20.11 ± 3.182; P=0.034). Combined effects 1.8-folds higher risk in patients with Tt genotype of Taq-I and short CAG repeat. Thus, association of FokI and TaqI VDR gene polymorphisms suggest VDR as an important genetic marker for urolithiasis. Further, patients with combination of Tt of Taq-I and short CAG repeat were at higher risk for stone formation.

Interleukin-1β and receptor antagonist (IL-1Ra) gene polymorphisms and the prediction of the risk of end-stage renal disease

Abstract Cytokines play an important role in the pathogenesis of kidney disease and its progression to end-stage renal disease (ESRD). Inflammation is regulated by the genes of the interleukin 1 (IL-1) gene cluster. Therefore, it was hypothesized that a polymorphism in this gene cluster may be associated with the risk of ESRD. Polymorphisms in the IL-1 gene cluster were examined in a cohort of 222 ESRD patients and 206 controls of similar ethnicity. These individuals were genotyped for IL-1 β (promoter –511 and exon-5 +3953) genes and a variable number of tandem repeats (VNTR) in the IL-1 receptor antagonist gene (IL-1Ra). There was significant difference in genotype frequencies between ESRD patients and control group for IL-1β (promoter region and exon-5) and IL-1Ra gene polymorphism (p<0.001, 0.006 andu200a<u200a0.001, respectively). A significant difference was observed in IL-1Ra for 1/1 (410/410) and 1/2 (410/240) genotypes, and the risk for ESRD was higher in those carrying the 1/1 genotype (p=0.014, ORu200a=u200a1.692, and p<0.001, ORu200a=u200a0.163). Also identified was a novel, rare allele of a single copy of 86 bp in ESRD patients as compared with the controls. The haplotype ‘T-E2-1’ frequency distribution between patients and controls revealed greater than threefold risk (p=0.001, ORu200a=u200a3.572, 95% CIu200a=u200a1.589–8.032). Genetic linkage between the IL-1β promoter region and exon-5 and between the IL-1β promoter and IL-1Ra of IL-1 gene demonstrated a strong association among the variants in controls (D′u200a=u200a0.42, p<0.001, and D′u200a=u200a0.39, p=0.001). Thus, the three polymorphisms within the IL-1 cluster are associated with ESRD. This finding is perhaps one of the strongest associations between genotype and ESRD reported, and it suggests that the IL-1 gene cluster affects the risk of development of ESRD.

Association of Urokinase Gene 3′-UTR T/C Polymorphism with Bladder Cancer

Introduction: Bladder cancer is a disease characterized by multiple recurrences. Some investigators assume urokinase to be involved in the causation of bladder cancer, although there is lack of genetic evidence. Our aim was to evaluate whether polymorphism of the urokinase gene is associated with transitional cell carcinoma (TCC) of the urinary bladder. Materials and Methods: The study included 100 patients (mean age 62.5 ± 10.2 years) with TCC of urinary bladder and 150 healthy controls (mean age 60 ± 11.5 years) living in the same area. Polymerase chain reaction (PCR)-based restriction analysis was used to identify the C/T polymorphism of the urokinase gene. Genotyping distribution and allelic frequencies between patients and controls were compared. Results and Conclusion: There was a significant difference in the frequency distribution of the urokinase gene 3′-UTR C/T polymorphism in bladder cancer patients as compared to the normal control group (p < 0.05), but no significant difference in allelic frequencies or in carriage rates between bladder cancer patients and normal controls were observed. Our study suggests that urokinase gene polymorphism may be associated with bladder cancer and can thus serve as a potential genetic marker in screening for the possible causes of bladder cancer. Perhaps analysis of patients with superficial bladder TCC and mutated urokinase might help clarify this aspect in large cohort studies in different populations.