Targeting tumor associated macrophages using clodronate-loaded PLGA nanoparticles

It is now widely accepted that tumor associated macrophages (TAMs) are vital for tumor growth. In this study, we propose a novel strategy against cancer by targeting TAMs using drug-loaded nanoparticles. PLGA NPs containing clodronate, a bisphosphonate compound, were prepared by w/o/w emulsion method. Clodronateloaded NPs showed a significant inhibitory effect on macrophage-like RAW264.7 cells while showing low toxicity towards CCL-110 human fibroblast cell line. Inteavenously injected NPs functionalized with a TAMtargeting LyP-1 peptide also showed preferential accumulation in 4T1 tumor bearing mice. Our preliminary results suggests that clodronate-loaded PLGA NPs functionalized with the LyP-1 peptide can be potential antitumor agents.