Nordamnacanthal and damnacanthal exhibit apoptotic and anti-proliferative effects in breast cancer (MCF-7, MDA-MB231, 4T1), promoting annexin V+ expression, G1 arrest, and modulation of apoptotic regulators such as p53, Bax, Bcl-2, XIAP, and ER-α (97–99). The gene discussed is ESR1; the disease is breast cancer.