Methylenetetrahydrofolate Reductase (MTHFR) Gene rs1801133 C>T Polymorphisms and Lung Cancer Susceptibility: An Updated Meta-analysis

Objective: The aim of this study was to investigate the methylenetetrahydrofolate reductase (MTHFR) gene rs1801133 C>T polymorphisms and lung cancer susceptibility by pooling openly published data. Methods: Electronic databases of Medline, Web of Science, Embase, Google scholar, CBM and CNKI were systematic searched to find the relevant studies related to MTHFR gene rs1801133 C>T polymorphisms and lung cancer susceptibility. The odds of TT, CT and CC alleles in lung cancer patients compared with healthy controls was pooled by the effect size of odds ratio (OR) and corresponding 95% confidence interval (95%CI) under random or fixed effect model. Publication bias was analyzed by Begg's funnel plot and Egger's line regression test. Results: Overall, twenty-one studies relevant to MTHFR gene rs1801133 C>T polymorphisms and lung cancer susceptibility were included. The pooled data showed subject with T allele had significant increased risk of developing lung cancer in dominant (OR=1.14, 95%CI: 1.01-1.28, p<0.05), recessive (OR=1.26, 95%CI:1.081.48, p<0.01) and homologous (OR=1.36, 95%CI:1.12-1.65, p<0.01) genetic model. Begg's funnel plot and Egger's line regression test showed significant publication bias in all genetic models. Conclusion: Based on present data, subjects with TT or CT alleles may have increased susceptibility to lung cancer. However, due to significant publication bias, the conclusion should be drawn with caution and should be proved by further well-designed case-control or cohort studies relevant to MTHFR gene rs1801133 C>T polymorphisms and lung cancer risk.