Phosphorylcholine-Based Stealthy Nanocapsules Decorating TPGS for Combatting Multi-Drug-Resistant Cancer

Improving the anticancer efficacy of chemotherapeutics not only demands for efficient delivery into tumor sites, but also always needs to combat the multidrug resistance of cancer. Here we attempted to conquer both these problems by decorating D-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) onto a phosphorylcholine-based stealthy nanocapsule. This TPGS-decorated stealthy nanocapsule, referred as nBSA-TPGS-Dox, conjugated anticancer drug doxorubicin (Dox) through an acid-responsive benzoic-imine bond. nBSA-TPGS-Dox was demonstrated to be stable in PBS and exhibited acid-responsive Dox release behavior. In vitro results showed this nanocapsule could be efficiently uptaken by the Dox-resistant HepG2/ADR human liver cancer cells through clathrin-mediated endocytosis and greatly prevented the Dox efflux, causing much more cytotoxicity than free Dox and non-TPGS-decorated nBSA-Dox. Furthermore, nBSA-TPGS-Dox exhibited much prolonged in vivo half-life compared to conventional PEGylated nanoparticles and achieved excellent tumor accumulation. Finally, this TPGS-decorated stealthy nanocapsule performed outstanding suppression of Dox-resistant tumor, much superior than non TPGS-decorated nBSA-Dox and free Dox. Thus, this TPGS-decorated stealthy nanocapsule provides a novel powerful nanomedicine platform for combatting multi-drug-resistant cancer.