ESR1 and breast cancer: To evaluate the in vitro proliferative activities of AS extract, four human breast cancer cell lines with different immunoprofiles, namely MDA-MB-361 (ER+HER2+), MCF-7 (ER+HER2-), SKBR3 (ER-HER2+), and MDA-MB-231 (ER-HER2-), were used.