VEGFR2 Specific Delivery of Multistage Nanovectors-

A nanomedicine-based approach to treat cancer by targeting blood vessel formation

Cancer cells are able to survive and grow in the human body due to the process of Vascular Endothelial Growth Factor Receptor-2 (VEGFR2)-mediated angiogenesis (formation of new blood vessels).  Preventing blood vessel formation by blocking the action of VEGFR2 is a viable option for controlling tumor growth, but its clinical application is only partially successful due to limitations in the efficiency of delivery of the anti-angiogenesis agents. The aim of the present study was to create multistage nanovectors (MSV) that specifically target the VEGFR2 of endothelial cells and hence have the potential to deliver therapeutic agents in a targeted manner, while avoiding biological barriers. The small size, specific shape and distinct chemical properties of the MSV make them a promising delivery system to blood vessels that support the growth of cancer cells. The study was performed by creating MSV that had anti-VEGFR2 antibodies conjugated to their surface and then using these particles to target the VEGFR2 receptor of an endothelial cell line (PAEC) in vitro. The results show that anti-VEGFR2 antibody conjugated to MSV bind to VEGFR2 receptors of endothelial cells in a specific manner and are internalized by the cells. These in vitro studies suggest that MSV conjugated with anti-VEGFR2 antibodies may be effective for targeting and hence inactivating the VEGFR2 of endothelial cells in blood vessels around tumors and therefore may have important clinical applications for anti-angiogenesis cancer therapy.