Trastuzumab blocks dimerization and activation of the HER2 receptor by binding the extracellular domain of HER2, inhibits shedding of the HER2 extracellular region to inactivate multiple intracellular signaling pathways, and mediates antibody-induced cytotoxicity to inhibit the proliferation of tumor cells29,30. Here, ERBB2 is linked to neoplasm.