Resistance of hepatocellular carcinoma to sorafenib can be overcome with co-delivery of PI3K/mTOR inhibitor BEZ235 and sorafenib in nanoparticles.

: The combination of BEZ235 with sorafenib (SFB) enhances anti-hepatocellular carcinoma (HCC) efficacy of the two agents. However, pharmacokinetic profiles in vivo and different endocytosis abilities of these two drugs hinder their therapeutic application.: In this work, we developed d-α-tocopheryl polyethylene glycol 1000 succinate - polycaprolactone polymer nanoparticles (NPs) for co-delivery of SFB and BEZ235 (SFB/BEZ235-NPs). Explored the anti-proliferative and pro-apoptotic effects of SFB/BEZ235-NPs through in vitro and in vivo experiments.: Stabilized SFB/BEZ235-NPs were prepared with optimized drug ratio, yielding high encapsulation efficiency, low polydispersity, and enhanced cellular internalization in HepG2 cells. Synergistic cytotoxicity and pro-apoptotic ability were documented. In vivo pharmacokinetic results revealed extended circulation and bioavailability of SFB/BEZ235-NPs compared with those of free drugs. SFB/BEZ235-NPs enhanced antitumor effectiveness in SFB-resistant HCC xenograft mouse models.: Taken together, the results of this study describe a promising strategy using SFB and BEZ235 in a nanoparticle formulation for treatment of SFB-resistant HCC.