Meta-analysis of the CYP1A2 -163C>A polymorphism and lung cancer risk

Many published studies have concerned associations between the CYP1A2 -163 C>A polymorphism and risk of lung cancer, but the results have been inconsistent. Therefore, we performed a meta-analysis to obtain a more precise estimate. We searched the PubMed database up to March 1, 2013 for relevant cohort and case-control studies. Supplementary search was conducted manually by searching the references of the included studies and relevant meta-analyses. A meta-analysis was performed using RevMan 5.2 software for calculation of pooled odds ratios (ORs) and relevant 95% confidence intervals (CIs) after data extraction. Finally, seven case-control studies and one nested case-control study involving 1,675 lung cancer patients and 2,393 controls were included. The meta-analysis showed that there was no association of CYP1A2 -163 C>A polymorphism with risk of lung cancer overall [(OR=0.89, 95%CI= 0.74-1.07) for C vs. A; (OR=0.73, 95%CI= 0.50-1.07) for AA vs. CC ; (OR=0.82, 95%CI= 0.62-1.09) for AC vs. CC; (OR=0.79, 95%CI= 0.58-1.07) for (AC+AA) vs. CC; and (OR=0.87, 95%CI= 0.67-1.13) for AA vs. (CC+AC)]. Subgroup analysis indicated that there was an associationbetween CYP1A2 -163C>A polymorphism and lung cancer risk for population-based controls, a trend risk for SCCL (squamous cell carcinoma of lung) and Caucasians. These results suggested that -163 C>A polymorphism is likely to be associated with risk of lung cancer compared with population-based controls.