ERBB2 and breast cancer: In this study we sought to (1) determine whether Th1 cytokines, tumor necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ), induce senescence and apoptosis in HER2-expressing breast cancer cells, assess the impact of (2) Th1 cytokines combined with simultaneous HER2 and HER3 blockade in HER2-expressing cells and (3) EGFR and HER3 blockade in TNBC cells.