CYP2C9: CYP2C9 accounts for about 20% of hepatic CYP content and metabolizes about 10% of therapeutically relevant drugs such as the anticoagulant warfarin, the anticonvulsant phenytoin, the antidiabetic drug tolbutamide, and numerous NSAIDs.340,341 CYP2C9 also is involved in the bioactivation of several carcinogens such as polycyclic aromatic hydrocarbons (PAHs) and heterocyclic aromatic amines,342,343 and the generation of endogenous active substances, especially EETs,344 leading to be associated with cancer risk. This evidence concerns the gene CYP2C9 and cancer.