Accordingly, an in vitro study of 102 HCC patient samples was performed that focused on the clearance changes for 10 CYPs–CYP1A2, 2A6, 2B6, 2C8, 2C9, 2C19, 2D6, 2E1, and 3A4/5. The gene discussed is CYP1A2; the disease is hepatocellular carcinoma.