Efficient Delivery of Therapeutic siRNA with Nanoparticles Induces Apoptosis in Prostate Cancer Cells

Gene silencing using small interfering RNA (siRNA) has shown significant potential in the treatment of cancer. Herein, we developed the lipid-polymer hybrid nanoparticles (PEG-LP/siRNA NPs) for siRNA delivery. The cell viability assay indicated that PEG-LP/siRNA NPs had negligible cell cytotoxicity. The cellular uptake efficiency of PEG-LP/siRNA NPs measured by flow cytometry was up to 94.4%. Importantly, in vitro gene knockdown experiments demonstrated that PEG-LP/siJnk-1 NPs could significantly downregulate the expression of Jnk-1 at both the mRNA and protein levels in DU145 cells. Gene knockdown of Jnk-1 could activate apoptosis in part by the mitochondrial pathway in DU145 cells. Moreover, the PEG-LP/siJnk-1 NPs could inhibit tumor growth in a DU145 xenograft murine model, suggesting its therapeutic promise in cancer therapy.