EGFR and neoplasm: Other anti-cancer MAbs that target receptors for growth or angiogenic factors expressed by tumor cells, like the epidermal growth factor receptors HER2 (trastuzumab and pertuzumab) and EGFR (cetuximab, panitumumab and necitumumab), or the vascular endothelial growth factor 2 (VEGFR2) (ramicirumab) act at least in part by inhibiting the growth or angiogenic signaling functions of the target receptors, and could therefore be constructed as IgG2 or IgG4 antibodies.