Cell Microenvironment-Controlled Antitumor Drug Releasing-Nanomicelles for GLUT1-Targeting Hepatocellular Carcinoma Therapy

In clinical therapy, the poor prognosis of hepatocellular carcinoma (HCC) is mainly attributed to the failure of chemotherapeutical agents to accumulate in tumor as well as their serious systemic toxicity. In this work, we developed actively tumor-targeting trilayer micelles with microenvironment-sensitive cross-links as a novel nanocarrier for HCC therapy. These micelles comprised biodegradable PEG-pLys-pPhe polymers, in which pLys could react with a disulfide-containing agent to form redox-responsive cross-links. In vitro drug release and pharmacokinetics studies showed that these cross-links were stable in physiological condition whereas cleaved once internalized into cells due to the high level of glutathione, resulting in facilitated intracellular doxorubicin release. In addition, dehydroascorbic acid (DHAA) was decorated on the surface of micelles for specific recognition of tumor cells via GLUT1, a member of glucose transporter family overexpressed on hepatocarcinoma cells. Moreover, DHAA exhibited a "one-way" continuous accumulation within tumor cells. Cellular uptake and in vivo imaging studies proved that these micelles had remarkable targeting property toward hepatocarcinoma cells and tumor. Enhanced anti-HCC efficacy of the micelles was also confirmed both in vitro and in vivo. Therefore, this micellar system may be a potential platform of chemotherapeutics delivery for HCC therapy.