MCF7, T47D, and ZR75.1 are estrogen receptor-positive (ER+); BT474, SKBR3, and MBA-MB-361 are human epidermal receptor 2 amplified and overexpressed (HER2+); and MDA-MB-453, MDA-MB-231, SUM159PT, and SUM185PE are triple-negative breast cancer cell lines (TNBC). This evidence concerns the gene ESR1 and triple-negative breast carcinoma.