Genetic polymorphism of MTHFR A1298C and esophageal cancer susceptibility: a meta-analysis.

BACKGROUND Associations between the methylenetetrahydrofolate reductase (MTHFR) A1298C polymorphism and esophageal cancer risk have been reported in many articles recently, but results were controversial. Therefore the present meta-analysis was conducted to to provide a more precise estimation. METHODS Odds ratios (ORs) with 95% confidence intervals (CIs) were used to evaluate the strength of associations. RESULTS Finally, six case- control studies involving a total of 1,302 cases and 2,391controls for the A1298C polymorphism were included. The meta-analysis showed that significantly increased risk for Asians (CC versus AA, OR=3.799, 95%CI=1.541-9.365, P=0.004; CCversusCA+AA, OR=3.997, 95%CI=1.614-9.900, P=0.003) and Caucasians (CC versus AA, OR=1.797, 95%CI=1.335-2.418, P=0.000; CC+CA versus AA,OR=1.240, 95%CI=1.031-1.492, P=0.022; CCversusCA+AA, OR=1.693, 95%CI=1.280-2.240, P=0.000). In addition, there was an association with risk for both ESCC (CC versus AA, OR=2.529, 95%CI=1.688-3.788, P=0.000; CCversusCA+AA, OR=2.572, 95%CI=1.761-3.758, P=0.000) and esophageal adenocarcinoma (EAC) (CC versus AA, OR=1.592, 95%CI=1.139-2.227, P=0.007; CC+CA versus AA,OR=1.247, 95%CI=1.016-1.530, P=0.035; CCversusCA+AA, OR=1.466, 95%CI=1.069-2.011, P=0.018). CONCLUSION This meta-analysis suggested associations of the A1298C polymorphism with increased risk of esophageal cancer in both Asians and Caucasians. In addition, we found that the MTHFR A1298C polymorphism might influence risk ofESCC and EAC in the overall studies.