A self-assembled system for tumor-targeted co-delivery of drug and gene.

A new cationic polymer eprosartan-graft-PEI (ESP) containing eprosartan (ES) and polyethylenimine 1.8K was successfully developed and employed as a safe gene vector to assemble a drug (ES) and gene co-delivery complex (ESP/pDNA). Chondroitin sulfate (CS) was then used as a coating polymer to shield the surface charge of ESP/pDNA complexes, as well as a tumor targeting entity to ensure specific delivery of CS/ESP/pDNA complexes. The CS/ESP/pDNA complexes with desirable particle size and zeta potential, exhibited amidase-responsive drug release and CS-mediated endocytosis in vitro. As compared with ESP/pDNA complexes, in vivo imaging results demonstrated decreased reticuloendothelial system uptake and remarkably increased tumor accumulation of CS/ESP/pDNA complexes. All these findings indicated the potential of CS/ESP/pDNA as a promising tumor-targeted drug and gene co-delivery system.