Objective: This study aimed to investigate the effects of multiwalled carbon nanotubes (MWNTs) co-delivering sorafenib (Sor) and epidermal growth factor receptor (EGFR) siRNA (MWNT/Sor/siRNA) on tumor growth in liver cancer (LC).

Results: MWNT/Sor/siRNA was proved to possess increased Sor release, high siRNA stability, and enhanced cellular uptake. In addition, MWNT treatment has few effects on cell proliferation and apoptosis in HepG2 cells; however, MWNT/Sor/siRNA treatment significantly inhibited clone number and induced cell apoptosis, which shows a more favorable antitumor effect than MWNT/Sor and free Sor and free siRNA in HepG2 cells. Moreover MWNT/Sor/siRNA treatment has the most significant antitumor effect in vivo.

Conclusions: MWNT/Sor/siRNA exhibited a superior antitumor effect in vitro and in vivo.

Methods: The MWNT/Sor and MWNT/Sor/siRNA were prepared, and then the morphologies of MWNT/Sor/siRNA were analyzed. In vitro Sor release assay, siRNA stability and cellular uptake of MWNT/Sor/siRNA were performed as well. Next, the effects of MWNT, free Sor, free siRNA, MWNT/Sor and MWNT/Sor/siRNA were evaluated by colony-forming assay, and cell apoptosis assay in HepG2 cells. Meanwhile, the level of EGFR and proteins associated with apoptosis was tested. Furthermore, the anti-tumor effects of MWNT/Sor/siRNA on LC xenograft mice were also unraveled.