Interleukin-1 genetic polymorphism: association with gastric cancer in the high-risk Central-Western population of Venezuela

Genetic predisposition may play a role in the prevalence of gastric cancer (GC). To investigate the relationship between selected interleukin-1 (IL-1) loci polymorphisms and gastric cancer risk in the Central-Western region of Venezuela, where gastric cancer represents the first cause of cancer-related deaths. In a case-control study we compared the frequencies of IL-1B-511 and IL-1B+3954 biallelic polymorphism, and the pentallelic VNTR of IL-IRN in 84 gastric adenocarcinoma paraffin-embedded biopsies and 84 endoscopic biopsies from cancer-free controls. No significant increase in genotypic frequencies in gastric cancer was observed for any of the IL-1B-511 allelic combinations. However, in a logistic regression analysis, a significant association emerged for the IL-1B+3954C carrier genotype (odds ratio (OR): 6.2; 95% confidence intervals (CI) 1.3-28.8). On the other hand, a significantly higher risk was evidenced for the IL-IRN*2/*2 genotype (OR: 7.0; 95% CI2.3-21.5). Only patients with a well/moderately-differentiated adenocarcinoma that were homozygotes for the E-IRN*2/*2 genotype, had a higher risk than the complete gastric cancer group (OR: 8.1, 95% CI 2.5-26.8). Some genotype combinations among IL-1B-511, IL-1B+3954 and IL-IRN showed an increased risk for developing gastric cancer and well/moderate differentiated adenocarcinoma, that was dependent of the presence of IL-IRN*2/*2 genotype. IL-IRN*2/*2 genotype is associated with increased risk of gastric cancer in the Venezuelan population.