ESR1 and breast cancer: To validate our hypothesis that EZH2 plays a significant role in NIC-mediated increased breast cancer progression without limiting to specific cell line, we included one normal breast epithelial cell line MCF-10A, two estrogen receptor positive cell lines T47D and MCF-7, and two aggressive estrogen receptor negative breast cancer cell lines MDA-MB-231 and MDA-MB-453 in the study where we found similar kind of results.