NCIt definition : A humanized monoclonal antibody directed against the domain II of the extracellular
domain of human epidermal growth factor receptor 2 (HER2; ErbB2; HER-2), with potential
antineoplastic activity. Upon administration, anti-HER2 monoclonal antibody QL1209
targets and binds to HER2 on HER2-expressing tumor cells. This prevents HER2-mediated
signaling and may lead to an inhibition of proliferation in HER2-expressing tumor
cells. HER2, a tyrosine kinase receptor, is overexpressed by many cancer cell types.;