FLT1 and cancer: For instance, polyplex micelles based on the self-assembly of PEG20kDa-poly{N0-[N-(2-aminoethyl)-2-aminoehtyl]aspartamide}-cholesteryl [PEGPAsp(DET)-cholesteryl] (PEG20C), and plasmid DNA encoding soluble vascular endothelial growth factor receptor-1 (sVEGFR-1) or soluble fms-like tyrosine kinase-1, sFlt-1 (endowed with antiangiogenic property), conjugated with cRGD peptide ligands, selectively targeting ⍺vβ5 and ⍺vβ3 integrin receptors [116], which are greatly expressed on cancer cells and tumor vascular endothelial cells [117,118,119,120].