ERBB2 and breast cancer: To study the effects of influenza virus infection on awakening of dormant breast DCC in the lung, we used the MMTV-erbB2/neu/HER2 mouse model (hereafter MMTVHer2) where mice overexpress rat Neu (Erbb2; paralog of human Her2) in epithelial mammary gland cells, a well-established mouse model of breast cancer metastatic dormancy14,38.