ERBB2 and breast cancer: Immunotherapies and targeted therapies implying the inhibition of human epidermal growth factor receptor 2 (HER2) signaling with either antibodies (e.g., trastuzumab and pertuzumab) or small molecule tyrosine kinase inhibitors (TKIs as lapatinib) have improved the outcomes of patients with HER2-positive (+) breast cancer [13,14].