ERBB2 and breast cancer: For modeling tumorigenesis in breast tissue, we use an inducible mouse model of breast cancer (TetO-MYC/TetO-Neu/MMTV-rtTA transgenic mice) (Fry et al., 2016; Moody et al., 2002; Podsypanina et al., 2008) that has been shown to recapitulate hallmarks of human breast disease (Havas et al., 2017; Jechlinger et al., 2009; Figure 1a).