Association of the IL-1B+3954 C/T polymorphism with the risk of gastric cancer in a population in Western China

With an estimate of 380 000 new cases each year, gastric cancer (GC) is one of the most frequently occurring cancers in China. Genes encoding proinflammatory and anti-inflammatory cytokines are good candidates for the study of susceptibility to GC. We tested the hypothesis that the polymorphisms of interleukin 1B (IL-1B) and IL-1RN contribute toward host susceptibility to GC. In a matched case-control design, we enrolled 308 pairs of GC and control participants between October 2010 and August 2011. We sequenced IL-1B +3954 C/T, IL-1RN -9876 G/A, -9739 A/G, and IL-1RN -9091 A/C using MALDI-TOF MS and collected demographic data as well as lifestyle factors using a questionnaire. GC patients reported statistically significantly greater proportions with family history of cancer (29.9 vs. 10.7%, P<0.01) and alcohol drinking (54.5 vs. 43.2%, P<0.01) than the controls. The proportion of irregular eaters was statistically higher among the patients than among the controls (66.7 vs. 24.4%, P<0.01). The IL-1B +3954 CT or the TT variant genotype was statistically significantly associated with a risk of GC [adjusted odds ratio (OR), 2.94; 95% confidence interval (CI), 1.06-8.15], whereas variants of IL-1RN -9876 G/A, IL-1RN -9739 A/G, and IL-1RN -9091 A/C were not associated (adjusted OR, 1.29, 95% CI, 0.77-2.16; adjusted OR, 1.25, 95% CI, 0.75-2.07; adjusted OR, 1.09, 95% CI, 0.71-1.67, respectively). Haplotypes established from the three polymorphisms of IL-1RN were not associated with a risk of GC. The IL-1B +3954 C/T polymorphism is associated with a risk of GC in our study. Lifestyle and environmental factors such as drinking, eating irregularly, and family history of cancer increase the risk.