To recapitulate BRCA1 deficiency in breast cancer, tumors derived from the K14-Cre-Brca1f/f;Trp53f/f immunocompetent genetically engineered mouse model of TNBC were orthotopically implanted into the mammary fat pads of FVB/129P2 syngeneic mice. Here, BRCA1 is linked to breast cancer.