The present study demonstrates the applicability of a novel strategy that employs targeted delivery of combined treatment against tumor neovasculature. Briefly, a ligand of integrins, cyclic arginine-glycine-aspartic acid-tyrosine-lysine pentapeptide (cRGDyK), was conjugated to the PEG end of polyethylene glycol-b-poly lactic acid (PEG-b-PLA), and doxorubicin was chemically linked to the PLA end of PEG-b-PLA. The targeted dual-drug micelle system was prepared by mixing combretastatin A4 (an antivascular agent), PEG-b-PLA, and the above two conjugates using a solution-casting method. The targeted micelles significantly enhanced cellular uptake of the drug by B16-F10 cells and human umbilical vein endothelial cells through a receptor-mediated endocytosis. The cRGDyK-modified dual-drug system achieved an optimal antitumor effect, lifespan increase, antineovasculature, antiproliferation, and apoptosis induction, revealing the advantage of active targeting and the modified combination therapy. In conclusion, the integration of targeted delivery and combination therapy against tumor neovasculature represents a promising approach for cancer treatment.
From the clinical editor: A ligand of integrins was conjugated to PEG-b-PLA, and doxorubicin was chemically linked to the PLA. Efficiency was demonstrated in a cancer model. The integration of targeted delivery and combination therapy against tumor neovasculature represents a promising approach for cancer treatment.
2012 Elsevier Inc. All rights reserved.