The genetically engineered mouse models TgMMTV-neu and C3(1)Tag were selected because they are immunocompetent models of breast cancer, their spontaneous tumors have similar immune environments to specific human breast cancer subtypes, and they are genetically similar to luminal B (TgMMTV-neu) and triple negative (C3(1)Tag) human breast cancer7,8. Here, ERBB2 is linked to breast cancer.