It is well known that MDA-MB-231 cells, which are epithelial cell carcinomas from estrogen receptor (ER−), progesterone receptor (PR−), and epidermal growth factor receptor 2 (HER2−) triple-negative breast cancer (TNBC), possess higher invasion and metastasis capability than MCF-7 cells, which are duct cell carcinomas with (ER+/PR+/HER2−) profile [2, 16, 27]. Here, ESR1 is linked to triple-negative breast carcinoma.