Novel nanostructured lipid-dextran sulfate hybrid carriers overcome tumor multidrug resistance of mitoxantrone hydrochloride

Novel nanostructured lipid-dextran sulfate hybrid carriers (NLDCs) were successfully developed for sustained delivery of water-soluble cationic mitoxantrone hydrochloride (MTO) and overcoming multidrug resistance. The introduction of negative polymer of dextran sulfate sodium significantly improved the encapsulation efficiency (97.4%) and sustained the release of MTO (86.9% at 72 hours). In vivo pharmacokinetics in rats after intravenous administration demonstrated that MTO-loaded NLDCs (MTO-NLDCs) had higher area under the curve and longer half-life than MTO solution (MTO-Sol). In the biodistribution study, NLDCs significantly improved the MTO levels in plasma, spleen, and brain, and decreased the distribution of MTO in heart and kidney. In comparison with MTO-Sol, MTO-NLDCs efficiently enhanced cytotoxicity through the higher accumulation of MTO in breast cancer resistance protein (BCRP)-overexpressing MCF7/MX cells. MTO-NLDCs entered into the resistant cancer cells by the clathrin-mediated endocytosis pathway, which escaped the efflux induced by BCRP transporter and thereby overcame the multidrug resistance of MCF-7/MX cells. From the Clinical Editor: In this study, novel nanostructured lipid-dextran sulfate hybrid carriers were synthesized and utilized for sustained delivery of mitoxantrone hydrochloride. The utilized methods successfully addressed multidrug resistance to this chemotherapy agent. (C) 2012 Elsevier Inc. All rights reserved.