ANPEP and cancer: Classical vascular-homing peptides arepeptides containing the NGR motif, which binds to aminopeptidase N(CD13) or the RGD motif, which binds to αν integrins.106 Aminopeptidase N is overexpressed by endothelialcells of tumor vasculature and has been demonstrated to be involvedin angiogenesis and cancer progression.