siRNA-loaded selenium nanoparticle modified with hyaluronic acid for enhanced hepatocellular carcinoma therapy.

Background: Small interfering RNA (siRNA) as a new therapeutic modality holds promise for cancer treatment. However, the traditional viral carriers are prone to immunogenicity and risk of insertional mutagenesis.

Methods: In order to provide a tumor-targeted delivery carrier of siRNA in cancer therapy, the hyaluronic acid (HA)-selenium (Se)-polyethylenimine (PEI) nanoparticle (NP) was fabricated by decorating SeNP with HA as a tumor-targeting moiety and by linking the polycationic polymers polyethylenimine PEI onto the surface of SeNP. The siRNA was loaded to the surface of SeNP HA-Se-PEI via the electrostatic interaction between siRNA and PEI to prepare the functionalized SeNP HA-Se-PEI@siRNA.

Results: The HA-Se-PEI@siRNA was internalized into the HepG2 cell mainly in a clathrin-mediated endocytosis manner. Owing to the active tumor-targeted effect mediated by HA, HA-Se-PEI@siRNA achieved the obvious higher transfection efficiency, greater gene silencing ability, and stronger cytotoxicity in the HepG2 cell compared with the passive tumor-targeted NP Se-PEI@siRNA. The knockdown of hairy and enhancer of split 5 by HA-Se-PEI@siRNA induced the HepG2 cell cycle arrest at the G0/G1 phase and apoptosis. Furthermore, the treatment with HA-Se-PEI@siRNA resulted in greater antitumor efficacy compared with the Se-PEI@siRNA in vitro and in vivo. In addition, the HA-Se-PEI@siRNA was almost no toxic to the key organs of mice.

Conclusion: These findings provided an alternative therapeutic route for targeted cancer treatments.