The IC50 of CSC-3436 in different types of breast cancer cell lines including TNBC (MDA-MB-231, MDA-MB-468, BT-549, and BT-20), ERα-positive (MCF-7 and T47D) and HER-2 amplified (BT-474) narrow down to nanomolar. The gene discussed is ESR1; the disease is breast carcinoma.