ERBB2 and breast cancer: We explored whether an exacerbated response of HER2-overexpressing breast cancer cells to oleuropein aglycone could be exploited to positively modulate the growth inhibitory effects of trastuzumab (HerceptinTM), a humanized monoclonal antibody binding with high affinity to the ectodomain of p185HER2 oncoprotein [38-40].