To this end, we used K14cre;Brca2del/del;p53del/del mouse mammary tumor cells (further denoted as Brca2−/−), together with an isogenic line in which BRCA2 expression was reconstituted using an infectious bacterial artificial chromosome (iBAC) containing the mouse Brca2 gene (denoted as Brca2iBAC) (Evers et al., 2008, 2010). This evidence concerns the gene BRCA2 and breast cancer.