In a recent study published in Nature Cancer, Shi et al. reported the identification of the small molecule YC-1 as the selective drug against primary liver tumor cells due to the specific expression of sulfotransferase family 1A member 1 (SULT1A1) in hepatocyte-lineage cells.1 This study offered new insights into repurposing an old anti-cancer drug via harnessing hepatocyte-specific metabolic enzymes to treat primary liver tumors. The gene discussed is SULT1A1; the disease is cancer.