Targeting liposomes to tumor endothelial cells for neutron capture therapy

The aim of our work is to target B-10 to the tumor vasculature for neutron capture therapy (NCT). Alpha (v)-integrin specific RGD-peptides were coupled to liposomes that encapsulated dodecahydrododecaborate. These RGD-liposomes strongly associated with human umbilical vein endothelial cells (HUVEC) expressing this integrin and were internalized. Proliferating HUVEC proved sensitive to treatment with gamma-irradiation resulting in decreased cell viability and pronounced inhibition of DNA-synthesis with increasing dose. Irradiation of RGD-B-10-liposome incubated HUVEC with neutrons strongly inhibited endothelial cell viability. These results suggest that efficient NCT can be achieved by targeting B-10-liposomes to angiogenic endothelium in tumors. (C) 2004 Elsevier Ltd. All rights reserved.