Association of Methylenetetrahydrofolate reductase genetic polymorphisms and folate intake with susceptibility of esophageal squamous cell carcinoma: A meta-analysis

Objectives: We conducted an update meta-analysis to investigate the association of MTHFR C677T and folate intake with esophageal cancer risk. Methodology: PubMed, EMBASE and the CNKI were searched in our study. The pooled Odds ratio (ORs) and 95% confidence intervals (CIs) of MTHFR C677T and folate intake and ESCC risk from each study were pooled using meta-analysis. Results: Twenty studies (4271 cases and 5559 controls) were included for meta-analysis. MTHFR 677 CT and TT genotypes were associated with an increased risk of ESCC, with OR(95% CI) of 1.48(1.25-1.77) and 1.65(1.24-2.20). By subgroup analysis, we found individuals carrying CT+TT genotype and low intake of folate had an increased risk of ESCC risk when compared with CC genotype [OR(95CI%)=1.55(1.02-2.57)]. There was a significant interaction between folate intake and ESCC. No publication bias was found among studies regarding MTHFR 677 CT and TT by Egger's test. Conclusions: Our meta-analysis indicated MTHFR 677CT and/or TT genotypes are associated with the risk of ESCC, and folate could modify their association.