Mammary Tumor Mouse Model Development

All animal studies were conducted under protocol 2016–1143 approved by the Georgetown University Animal Care and Use Committee in accordance with NIH guidelines for the ethical treatment of animals. MMTV-NeuT mice [46 (link)] were obtained from Jackson Labs (FVB-Tg(MMTV-Erbb2)NK1Mul/J), and exhibit 100% penetrance of mammary tumorigenesis by 6–7 months [47 (link)]. FAT-ATTAC mice on a C57BL/6 background were kindly provided by Dr. Philipp Scherer, University of Texas Southwestern [28 (link), 48 (link)]. Mice were crossed into the FVB strain for four generations before crossing with MMTV-NeuT mice to produce NeuT/ATTAC mice. A schematic of the breeding is shown in Figure 1A.