The pooled estimate revealed an association between IL-17A rs2275913 polymorphism and the risk of GC under all genetic models (A vs. G, OR 1.187, 95% CI 1.086-1.297, P < 0.001; GA vs. GG, OR 1.108, 95% CI 1.008-1.218, P = 0.033; AA vs. GG, OR 1.484, 95% CI 1.236-1.781, P < 0.001), while no evidence of association was found with IL-17A rs3748067 or IL-17F rs763780 polymorphisms.
In conclusion, our results suggest that the IL-17A rs3748067C>T and IL-17F rs763780 T>C polymorphisms play an important role in the risk of gastric cancer in a Chinese population.
The rs2275913 AA (adjusted OR = 1.69, 95 % CI = 1.15-2.49) and rs3748067 TT (adjusted OR = 1.73, 95 % CI = 1.03-2.94) genotypes were associated with an increased risk of gastric cancer.
A significant interaction was observed between the rs2275913G>A and rs3748067C>T genotype and subsites of gastric cancer (p for interaction of 0.044 and 0.008, respectively).
However, no significant positive signals were observed in the association analysis of the rs3748067 and rs763780 polymorphisms with the risk of gastric cancer in IL-17A and IL-17F, respectively.
The rs3748067 T polymorphism was associated with a decreased risk for intestinal GC (OR, 0.511; 95%CI, 0.272-0.962; p = 0.037), whereas rs2505901 C locus carried a decreased risk overall for GC (OR, 0.733; 95%CI, 0.545-0.985; p = 0.039).