Effective siRNA therapy of hepatoma mediated by a nonviral vector with MRI-visibility and biodegradability

Abstract

Although RNA interference (RNAi) has demonstrated great potential in tumor therapy in recent years, the lack of an effective approach for non-invasive monitoring of in vivo siRNA delivery is still impeding its clinical application. Based on the biodegradable and redox-sensitive cationic polymer synthesized in our lab, an MRI-visible nanocarrier was prepared to codeliver siRNA and SPIO into HepG2 cancer cells. The highly efficient codelivery of siRNA and SPIO were achieved both in vitro and in vivo. Consequently, the survivin-specific siRNA delivered with the vector could effectively suppress the survivin gene expression and promote hepatic tumor cell apoptosis. Moreover, incorporation of SPIO made the siRNA delivery and therapy trackable with noninvasive magnetic resonance imaging (MRI), which in turn may provide real-time and reliable information to guide the optimization of carrier properties for targeted siRNA delivery.