IL-1β Polymorphism and Expression Associated with Decreased Risk of Gastric Carcinoma: a Case Control Study in the Ethnic Kashmiri Population, India

Abstract

The aim of this research was to investigate the possible association between gastric carcinoma (GC) andpolymorphisms of the IL-1β gene in the Kashmiri population using peripheral blood DNA from 150 gastriccarcinoma cases and 250 population controls with detailed data for clinicopathological characteristics of thedisease. Two SNPs in the IL-1β gene were selected for this study. Expression of IL-1β was studied in 50 gastriccarcinoma cases using immunohistochemistry and RT-PCR and then correlated with genotype. The frequencyof the IL-1β-511 C allele was significantly higher in the GC case group (53.3%) than in controls (45.4%) withan odds ratio (OR) of 0.73 and a P value of 0.03. Multivariate regression analysis showed associations of gastriccarcinoma with mutant form of IL-1β-511 TT (OR 0.309; P value <0.001) and the CC genotype of IL-1β-31(OR 0.313; P value of 0.002). Haplotype analysis of IL-1β-31 and IL-1β-511 showed decreased association of IL-1β-31 T with IL-1β-511 C with gastric carcinoma (OR 0.728; P value 0.03). Expression study of 50 samples byimmunohistochemistry (IHC) and RT-PCR showed association with grade III and stage III+IV. After correlatingthe expression with polymorphism no association was found.