ESR1 and triple-negative breast carcinoma: Immunohistochemical analysis of the chemoresistant and sensitive groups showed that the expression changes of most of the genes found in MCF-7 cells were more consistent with those from triple-negative breast cancer (TNBC) patients, than from all individuals regardless of their estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (Her2) status.