CYP3A5*3 polymorphism and cancer risk: a meta-analysis and meta-regression.

CYP3A5 is a cytochrome P450 superfamily member which is involved in the metabolism of drugs, steroid hormones, and other xenobiotics. Emerging evidences suggest that CYP3A5*3 (rs776746 A>G) polymorphism may play a role in the etiology of carcinogenesis and affect an individual's susceptibility to cancer in humans, but individually published studies showed inconclusive results. This meta-analysis aimed to derive a more accurate estimation of the correlation between CYP3A5*3 polymorphism and cancer risk. A literature search of PubMed, Embase, Web of Science, and China BioMedicine databases was conducted on articles published before January 1, 2013. Seventeen case-control studies were included with a total of 7,458 cancer patients and 7,166 healthy controls. The meta-analysis results showed that CYP3A5*3 polymorphism may increase the risk of cancer, especially in acute leukemia, chronic leukemia, and colorectal cancer. However, no statistically significant associations were found in prostate cancer, liver cancer, and other cancers. Further subgroup analysis by ethnicity indicated that CYP3A5*3 polymorphism was associated with an increased risk of cancer among Asian and Caucasian populations, but not among African populations. In conclusion, the current meta-analysis suggests that CYP3A5*3 polymorphism may play an important role in the development of acute and chronic leukemia and colorectal cancer, especially among Asian and Caucasian populations.