ESR1 and breast cancer: A recently published study also confirms a pro-tumourigenic role of AT1R demonstrating that overexpression of AT1R in an ER+ve breast cancer cell line resulted in increased proliferation, increased expression of poly(ADP-ribose) polymerase (PARP) and X-linked inhibitor of apoptosis (XIAP), increased ERK, p-Smad3/4 activation [39].