BRCA1 and cancer: The relationship between expression profiles of HRR and EMT genes might be explained by the following hypotheses: (1) the co-existence of deficient BRCA1/2 or HRR genes and altered expression of EMT genes together lead cancer cells to extinction; or (2) altered expression of EMT genes may contribute to the tumor microenvironment being nonviable for cancer cells with defects in BRCA1/2 or HRR genes.