[Correlation of interleukin-10-1082G/a single nucleotide polymorphism to the risk of gastric cancer in north China: a case-control study]

Abstract

Background & objective: The individual genetic susceptibility is important in the development of gastric cancer. The 1082G/A single nucleotide polymorphism (SNP) of interleukin-10 (IL-10), an immune suppressor gene, became a research hot spot in this field. This study was to analyze the distribution of IL-10-1082G/A SNP in a population from northern China, and explore its correlation to the susceptibility to gastric cancer.

Methods: Blood samples were taken from 983 subjects in a high risk area of gastric cancer and 533 in a low risk area. The genotype of IL-10-1082G/A was analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Serum level of anti-Helicobacter pylori (H. pylori) IgG was measured by enzyme-linked immunosorbent assay. Matched by sex and age, 111 specimens of normal gastric mucosa (NOR), 111 specimens of superficial gastritis (GS), 111 specimens of gastric erosion ulcer (GEU), 111 specimens of atrophic gastritis (AG) and 111 specimens of gastric cancer (GC) were selected to analyze the correlation of IL-10-1082G/A SNP to the susceptibility to gastric cancer.

Results: The detection rates of IL-10-1082 AA, AG, GG genotypes in the 1516 subjects were 88.5%, 10.9% and 0.6%, respectively. There were no differences in region and sex distribution of IL-10-1082AG+GG genotype between the high and low risk areas of gastric cancer. The detection rate of IL-10-1082 AG+GG genotype was significantly higher in gastric cancer than in benign lesions and normal mucosa (19.8% vs. 9.7% and 6.3%, P=0.003). As compared with the subjects with IL-10-1082 AA genotype and without H.pylori infection, the subjects with AG+GG genotype and without H.pylori infection [odds ratio (OR)=3.3, 95% confidence interval (CI)=1.3-8.6], the subjects with AA genotype and H.pylori infection (OR=4.3, 95% CI=2.0-9.5) and the subjects with AG+GG genotype and H. pylori infection [OR=2.5, 95% CI=2.1-3.1] had higher susceptibility to gastric cancer, but there was no significant difference between every 2 of the 3 groups (P>0.05).

Conclusions: The susceptibility to gastric cancer is higher in the subjects with IL-10-1082 AG+GG genotype. There is no synergism between IL-10-1082G/A SNP and H.pylori infection.