CYP2C9 and cancer: Benzo[a]pyrene can be metabolized by CYP2C subfamily members and finally transformed into DNA adducts, including (+)‐trans‐benzo[a]pyrene‐7, 8‐dihydrodiol‐9, and 10‐oxide (BPDE)‐N2‐dG, which are known to induce cancers of the skin, lung, and stomach (Fig. 2).