Conjugation of bevacizumab to cationic liposomes enhances their tumor-targeting potential

Cationic liposomes have been shown to preferentially target the tumor vasculature, but not uniformly. Bevacizumab antibody selectively accumulates in tumors expressing VEGF. We thus developed bevacizumab-modified, pegylated cationic liposomes (PCLs) to improve the distribution of liposomes along tumor vessels, and to enhance tumor targeting.

We evaluated the delivery vehicle both in the absence and presence of VEGF, using human pancreatic cancer (Capan-1, HPAF-II and PANC-1) and endothelial (MS1-VEGF and HMEC-1) cell lines.

All cell lines except for HMEC-1 secreted VEGF. Modification of PCLs with bevacizumab did not alter zeta-potential, but increased overall liposome size. The toxicity profile for bevacizumab-modified PCLs was cell line dependent and, in general, bevacizumab improved cellular uptake and tumor targeting of PCLs.

Bevacizumab-modified PCLs represent a potential improvement over the unmodified variety, supporting their future development for the treatment of cancer.