John Park, M.D., leads a group that is trying to develop antibody-targeted liposomal nanoparticles for treating cancer. Earlier work from this team had shown that drug-loaded liposomes can effectively deliver anticancer agents to brain tumors, but Park and his colleagues wanted to improve the delivery of drug-loaded liposomes so that they better targeted tumor cells. To do that, the investigators used an antibody that targets the tumor cell-surface protein HER2. They then dosed animals bearing HER2-overexpressing breast tumors with these targeted nanoparticles.
Data from this study showed that the antibody-targeted liposomes were no better at increasing the amount of drug that reached tumors. However, the antibody-targeted tumor cells delivered up to six times more drug into cells than did non-targeted, drug-laden liposomes. The research hypothesized that antibody binding to its target triggers endocytosis, a process that cells use to engulf large biomolecules for internalization. This work is reported in the journal Cancer Research.