Abstract: Angiogenesis plays an important role in tumor development and metastasis, and many cancer cells upregulate VEGF expression to promote angiogenesis. Silencing VEGF expression by RNA interference is expected to be a promising strategy to suppress the tumor growth. However, low transfection efficiency and instability are the main barriers for small interfering RNA (siRNA) delivery. In this study, we developed polycation liposome-encapsulated calcium phosphate nanoparticles (PLCP) for siRNA delivery in vivo. VEGF expression silencing effect in MCF-7 cells was investigated by real-time quantitative polymerase chain reaction and Western blot assay. VEGF siRNA mediated by PLCP can reduce 60%–80% VEGF expression in vitro, which was significantly higher than that mediated by Lipofectamine 2000. Furthermore, significant tumor growth and angiogenesis inhibition were observed in MCF-7 xenografts mice when treated with PLCP/VEGF siRNA or combined with doxorubicin. In conclusion, the combination of silencing VEGF expression and chemotherapeutics would be a potential treatment for cancer therapy.
Keywords: polycation liposomes, calcium phosphate nanoparticles, VEGF, siRNA, angiogenesis inhibition