Association between the COMT 158 G/A polymorphism and lung cancer risk: a meta-analysis

Catechol-O-methyltransferase (COMT) 158 G/A gene polymorphism seem to associate with lung cancer, but the results are inconclusive. This meta-analysis aims to investigate the association between COMT 158 G/A gene polymorphism and lung cancer susceptibility. We searched PubMed, Embase, China National Knowledge Infrastructure (CNKI), VIP Chinese science and technology periodical database (VIP) and Wanfang databases up to March 25, 2015 for articles on the connection between the COMT 158 G/A polymorphism and the risk of lung cancer. Pooled odds ratio (OR) and corresponding 95% confidence interval (CI) were used to estimate the connection. STATA (Version 12.0) was adopted for data analysis. Overall, 6 articles of 7 studies including 2,293 cases and 2,768 controls were included in our meta-analysis. In general analysis, no significant association was found between COMT 158 G/A polymorphism and the risk of lung cancer (AA + AG vs. GG: OR 1.14, 95% CI 0.90-1.44, P=0.28). However, in subgroup analysis of different method of genotyping, we found significant increase of lung cancer risk (OR 1.30, 95% CI 1.04-1.62, I(2)=61.5%, P=0.02), also there was significant association between COMT 158 G/A polymorphism and the risk of lung cancer in Chinese non-smoker women of unsorted cancer type (OR 1.48, 95% CI 1.24-1.77, I(2)=0%, P=0.00). The study indicates that COMT 158 G/A G->A gene transition might contribute to lung cancer, especially in Chinese non-smoker women.