Polymorphisms in interleukin-1B (IL-1B) and interleukin 1 receptor antagonist (IL-1RN) genes associate with gastric cancer risk in the Chinese population.

Background: Gastric cancer is one of the most common malignancies afflicting the Chinese population. Polymorphisms in interleukin-1B (IL-1B) and interleukin-1 receptor antagonist (IL-1RN) genes have been associated with increased gastric cancer risk.

Aims: A case-control study enrolled 392 gastric cancer patients and 508 healthy were carried out to investigate the association between polymorphisms in IL-1B and IL-1RN and gastric cancer risk.

Methods: Polymerase chain reaction (PCR)-restriction fragment length polymorphism was used for detection of two potentially functional polymorphisms (IL-1B-31 and IL-1B-511) in the IL-1B gene promoter and PCR was used for detection of the variable tandem repeat in the second intron of IL-1RN.

Results: The data showed that the IL-1B-31CC genotype increased gastric cancer risk to an adjusted odd of 2.27 (95% CI, 1.49-3.46), IL-1B-31CT to 1.48 (95% CI, 1.01-2.16) and IL-1B-31CT/CC to 1.68 (95% CI, 1.17-2.40), while IL-1B-51TT genotype associated with increased gastric cancer risk to an adjusted odd of 2.53 (95% CI, 1.67-3.84), IL-1B-511TC to 1.45 (95% CI, 1.02-2.06), and IL-1B-511TC TT/TC to 1.72 (95% CI, 1.23, 2.39). Furthermore, IL-1RN heterogeneity genotype (IL-1RN2L) was associated with gastric cancer risk to an adjusted odd of 1.70 (95% CI, 1.05-2.74) compared to the wild-type homozygote (IL-1RNLL). In addition, H. pylori infection enhanced gastric cancer risk through these SNPs.

Conclusions: The data from the current study demonstrated that the genotype CC or CT of IL-1B-31, TT or CT of IL-1B-511, and 2L of IL-1RN increased risk of gastric cancer in this Chinese population and the risk was further enhanced by H. pylori.