Polymorphisms in IL-10 and TGF-β gene promoter are associated with lower risk to gastric cancer in a Mexican population.

Background: Helicobacter pylori infection is recognized as the main risk factor for gastric cancer (GC), the fifth most common neoplasia worldwide. H. pylori interacts with the immune system, disrupting the cytokine network and inducing chronic inflammation. This work aimed to evaluate the association between single nucleotide polymorphisms (SNPs) in selected cytokine gene promoters and GC.

Methods: The study included 359 subjects, 125 GC patients, 109 intestinal metaplasia (IM) patients and 125 asymptomatic controls. DNA was extracted from white blood cells and nine SNPs in cytokine gene promoters were genotyped using predesigned 5'-endonulease assays. The association of the SNPs with IM and GC was evaluated using multinomial regression models.

Results: Both genotypes, TC (OR = 0.51, 95% CI = 0.27-0.98) and TT (OR = 0.42, 95% CI = 0.20-0.91) in the locus - 509 of the TGF-β promoter were significantly associated with GC. The TT genotype in the locus - 819 of the IL-10 promoter was also significantly associated with GC (OR = 0.37, 95% CI = 0.17-0.81). No significant association was found with SNPs IL-4 -590 T/C (rs1800629), IL-6 -573G/C (rs1800796), IL-10 -592C/A (rs1800872), IL-10 -1082A/G (rs1800896), and, IFN-γ -1615C/T (rs2069705).

Conclusions: SNPs in TGFβ (- 509 C/T, rs1800469) and IL-10 (- 819 C/T, rs1800871) promoters were associated with a lower risk for GC in a Mexican population.