ERBB2 and breast cancer: The production of chimeric or humanized mAbs with lower immunogenicity than murine mAbs prompted the clinical development of immunotherapy, and the anti-tumor effects reported with trastuzumab in breast cancer (BC) expressing HER2 and of the anti-CD20 rituximab in B-cell non-Hodgkin lymphoma demonstrated for the first time the high potential of mAbs for cancer therapy.