Journal of biomedical nanotechnology

Gene delivery with active targeting to ovarian cancer cells mediated by folate receptor alpha.

PMID 23802413


Folate receptor alpha (FRalpha) is overexpressed on ovarian cancer cells and is a promising molecular target for ovarian cancer gene therapy, but there was still no related report. In this study, folate modified cationic liposomes (F-PEG-CLPs) for ovarian cancer gene delivery were developed for the first time. Folate-poly(ethylene glycol)-succinate-cholesterol (F-PEG-suc-Chol) was firstly synthesized and then used to prepare folate-targeted cationic liposomes/plasmid DNA complexes (F-targeted lipoplexes). F-targeted lipoplexes were prepared by post-insertion method, and displayed membrane structure by transmission electron microscopy observation with the diameter of 193 nm-200 nm and the zeta potential of 35 mV-38 mV. DNase degradation experiments showed that plasmid DNA could be effectively shielded by F-targeted lipoplexes in vitro. F-targeted lipoplexes could transfer gene into human ovarian carcinoma cell line SKOV-3, and 0.1% F-PEG-CLPs composed by DOTAP/Chol/mPEG-Chol/F-PEG-suc-Chol (50:45:5:0.1, molar ratio) had the highest transfection efficiency. The transfection activity of F-targeted lipoplexes could be competitively inhibited by free folic acid, demonstrating that folate-FRalpha interaction caused high transfection efficiency of F-targeted lipoplexes. The uptake mechanism of F-targeted lipoplexes was further validated on human oral carcinoma cell line KB and human liver carcinoma cell line HepG2. The concentration-dependent and time-dependent cytotoxicity of targeted material F-PEG-suc-Chol was observed by MTT assay on SKOV-3 cell and its application would not increase the cytotoxicity of F-targeted lipoplexes in SKOV-3 cells. All the data indicated that F-PEG-CLPs would be a promising gene vector targeting for ovarian cancer therapy.