ESR1 and breast cancer: Induction by such drugs of a decrease of efficiency of signal transductions initiated by the putative action of ERαABs at the level of HER2 might alter growth of breast cancer cells, which in connection with the known antibody-dependent cellular cytotoxicity (ADCC) of these compounds related to their ability to recruit and activate natural killer cells (NK) would generate a major curative effect, even in the absence of ERα.