A semi-quantitative food frequency questionnaire was used to assess the dietary intake of six flavonoid subclasses (flavonols, flavones, flavanones, flavan-3-ols, anthocyanidins, and isoflavones) in 923 patients with colorectal cancer and 1,846 controls; furthermore, CYP1A1 genetic variants (rs4646903 and rs1048943) were genotyped.
This meta-analysis demonstrated CYP1A1 rs1048943 A > G may increase the susceptibility to CRCinstead ofrs4646903 T > C. This conclusion suggested CYP1A1 may contribute to the pathogenesis of CRC.
CYP1A1*2A (6235 T/C, rs4646903, MspI) is thought to be associated with an increased risk of CRC because of its role in metabolic activation of polycyclic aromatic hydrocarbons; however, the results of previous studies are conflicting.