CYP2D6 and hepatocellular carcinoma: Considering that talazoparib is already used in the clinical setting, and consistently demonstrated CYP2D6-dependent cytotoxicity in both HEK293T and HepG2 spheroids, we proceeded to culture and treat human hepatocellular cancer organoids from 11 patients with talazoparib (two-tailed t-test, Fig. 5c).