Improved antitumor activity of epirubicin-loaded CXCR4-targeted polymeric nanoparticles in liver cancers.

A liver-targeted drug delivery system (CX-EPNP) composed of PLGA/TPGS was prepared and characterized. The surface of nanoparticle was conjugated with LFC131 peptide to increase the specific interaction of carrier with CXCR4 overexpressing liver cancers to enhance the Epirubicin (EPI) delivery to tumors. The particles were nanosized with size than 150 nm and portrayed a sustained release kinetics suggesting its suitability for cancer targeting. The in vitro cell uptake results showed that the introduction of LFC131 to the nanoparticles could increase significantly the affinity to human hepatic carcinoma cells (HepG2) with approximately a 3-fold improvement in cellular uptake than non-targeted one. A specific receptor-mediated uptake was observed by confocal laser scanning microscopy. In addition, CX-EPNP showed remarkable cytotoxicity towards HepG2 cells, and could effectively inhibit tumor growth. The more significant EPI accumulation from CX-EPNP in the cancer cells gave rise to the enhanced EPI cytotoxicity and cell apoptosis. The CX-EPNP distributed mostly in the xenograft tumor after intravenous administration to mice and adequately remained in the blood for at least 24h. It seemed that CX-EPNP upon intravenous injection avoided rapid recognition by Kupffer cells and adequately remained in the blood. These findings suggest that CX-EPNP could effectively inhibit the growth of liver tumors in situ and could potentially reduce the systemic side effects. However, extensive investigation is still needed to assess the possible applications of the CX-EPNP in humans.