BRCA1 and breast cancer: Finally, we have demonstrated that loss of p16 or p18 rescues the premature senescence of MECs caused by Brca1 deficiency [11, 31, 33, 34] and that loss of Brca1 in p16- or p18-deficient mice leads to the development of mammary tumors resembling BLBC accompanied by features of EMT [11, 31].