[The correlation between polymorphisms of Toll-like receptor 2 and Toll-like receptor 9 and susceptibility to gastric cancer].

OBJECTIVE: To explore the relationship between the polymorphisms of Toll-like receptor 2 (TLR2) and TLR9 and the susceptibility to gastric cancer. METHODS: A population-based case-control study was conducted at Linqu county, Shandong province, China, including a total of 248 cases of gastric cancer. Another total of 496 age and sex-matched controls were randomly selected from the same cohorts. TLR2 rs3804099 and TLR9 rs187084 were detected by polymerase chain reaction-restriction fragment length polymorphism method. Odds ratios (ORs) and 95% confidence interval (CI) were computed from logistic regression models after adjusting for age, sex, Helicobacter pylori (H. pylori) infection and smoking status. RESULTS: The frequencies of TT, TC and CC genotype on TLR2 rs3804099 in control group were 43.5% (216/496), 46.6% (231/496) and 9.9% (49/496), respectively; whereas those in case group were 53.2% (132/248), 39.9% (99/248) and 6.9% (17/248), respectively. Significant differences in the frequencies of TLR2 rs3804099 were found between case and control groups (χ(2) = 6.665, P = 0.036). It was found that compared with the TT genotype, TC + CC genotype carriers obviously less susceptible to gastric cancer (OR = 0.68, 95%CI: 0.50 - 0.93). Joint effects analysis indicated that the TLR2 rs3804099 TT genotype carriers and H.pylori infectors had higher susceptibility to gastric cancer(OR = 3.42, 95%CI: 2.16 - 5.42), compared with TC + CC genotype carriers and non-H.pylori infection group. The frequencies of TT, TC and CC genotype on TLR9 rs187084 in control group were 33.3% (165/496), 49.0% (243/496) and 17.7% (88/496), respectively; whereas those in case group were 35.9% (89/248), 50.0% (124/248) and 14.1% (35/248), respectively. No significant association with gastric cancer was observed for TLR9 rs187084 polymorphism (χ(2) = 1.684, P = 0.431). CONCLUSION: Our findings indicate that TLR2 rs3804099 is closely associated with susceptibility to gastric cancer.