We therefore tested the anti-cancer activity of the drugs individually and combined on breast cancer cell lines from the major molecular subtypes, MDA-MB-231 (TNBC), T47D (ER+/PR+), MCF7 (ER+/PR−), and BT-474 (HER2+), and looked for potential synergy between the two drugs. The gene discussed is ERBB2; the disease is breast cancer.