In order to find out the relationship between the anticancer potency and the PARP-1 suppression effect, the most effective compounds as PARP-1 inhibitors (4, 5, 8a, 10b, 11b) were further evaluated for their in vitro cytotoxicity against the mutant BRCA1 (MDA-MB-436, breast cancer) using an MTT assay [37]. The gene discussed is BRCA1; the disease is breast cancer.