Association between cytochrome P450 2C9 gene polymorphisms and colorectal cancer susceptibility: evidence from 16 case-control studies.

Previous epidemiological studies have evaluated the association between common variations of cytochrome P450 (CYP)2C9 (430C>T and 1075A>C) and the risk of colorectal cancer (CRC) with conflicting results. To derive a more precise estimation of the relationship between these CYP2C9 polymorphisms and CRC, a meta-analysis was performed. PubMed, Embase, CNKI, and Web of Science databases were searched. A total of 16 studies including 9,463 cases and 11,416 controls were identified. Potential sources of heterogeneity including ethnicity, sample size of study, genotyping method, diagnostic criteria, and outcome were systematically assessed. Overall, the summary odds ratio of 430T variant for CRC was 0.92 (95% confidence interval (CI) 0.86-0.98; P = 0.012) and 1.39 (95% CI 1.07-1.81; P = 0.013) for colorectal adenomas (CRAs). As for CYP2C9 1075A>C polymorphism, no significant results were observed in overall and subgroup analysis. There was no evidence of publication bias. In conclusion, there is evidence to indicate a significant association between CYP2C9 430C>T polymorphism and CRC/CRA risk.