Ligands used for drugs and drug delivery platforms to tumor vasculature include antibody fragment L19 [31], as well as several cyclic and linear derivatives of the oligopeptide RGD and NGR, which bind to angiogenic endothelium through the integrins (α2bβ3, αvβ3, and α5β1) and aminopeptidase-N (CD13), respectively [32, 33]. This evidence concerns the gene ANPEP and neoplasm.