Previous case-control studies on the association of the angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism with gastric cancer were controversial. A meta-analysis was conducted to further evaluate the association between polymorphism in the ACE gene I/D and gastric cancer. We searched MEDLINE (PubMed), EMBASE, Web of Science, and CBM without language restrictions to Nov 20, 2014. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of association. Eight studies involving 1480 gastric cancer cases and 3773 cancer-free controls were included. Overall, no significant association between ACE I/D polymorphism and gastric cancer risk was observed (OR = 1.15; 95% CI 0.90-1.46, P = 0.26). The subgroup analysis on the basis of H. Pylori status showed the decreased gastric cancer risk in H. Pylori negative subgroup (OR = 0.40; 95% CI: 0.27-0.59; P < 0.00001) rather than in H. Pylori positive subgroup (OR = 1.82, 95% CI: 0.87-3.82, P = 0.11). Subgroup analysis was performed according to ethnicity (Caucasian and Asian). The results showed no genetic effects between ACE I/D polymorphism and gastric cancer risk. This meta-analysis suggested that the ACE gene I/D polymorphism was associated gastric cancer risk in H. Pylori negative subjects.
Keywords: ACE; Gastric cancer; gene polymorphism; meta-analysis.