A pH-sensitive gene delivery system based on folic acid-PEG-chitosan - PAMAM-plasmid DNA complexes for cancer cell targeting.
In this study, pH-sensitive biomaterials coated polymer/DNA nanocomplexes containing a high mobility group box 1 (HMGB1) were developed as an efficient non-viral gene delivery system. HMGB1 is a family of endogenous molecules that contains nuclear locating sequences (NSL). Polyethylene glycol tethered carboxylated chitosan modified with folic acid (FA-PEG-CCTS) was synthesized and its buffering capacity was determined by acid-base titration. A pH-sensitive core-shell system FA-PEG-CCTS/PAMAM/HMGB1/pDNA nanocomplexes (FPCPHDs), was prepared and characterized. Electrophoresis showed that FPCPHDs were resistant to heparin replacement and DNase I digestion. FPCPHDs exhibited only minor toxic effects on HepG2 and KB cells. The results of both luciferase activity assay and RFP fluorescence intensity analysis showed that FPCPHDs enhanced gene transfection and expression in KB cells. Moreover, gene transfection and expression in KB cells were inhibited by free folic acid. Intracellular trafficking of FPCPHDs in KB cells showed that FPCPHDs could rapidly escape from endo-lysosomes and become exclusively located in the nucleus at 3 h post transfection. In addition, FPCPHDs exhibited increased red fluorescence protein (RFP) expression at the tumor site of S180 xenograft nude mice. All results suggest that FPCPHDs is an efficient approach to improve the transfection and expression efficiency in most FR-positive cancer cells.
['Wang|Mingyue|M|', 'Hu|Haiyang|H|', 'Sun|Yuqi|Y|', 'Qiu|Lipeng|L|', 'Zhang|Jie|J|', 'Guan|Guannan|G|', 'Zhao|Xiuli|X|', 'Qiao|Mingxi|M|', 'Cheng|Liang|L|', 'Cheng|Lifang|L|', 'Chen|Dawei|D|']
D000818:Animals D045744:Cell Line, Tumor D048271:Chitosan D004247:DNA D050091:Dendrimers D005260:Female D005492:Folic Acid D018014:Gene Transfer Techniques D056945:Hep G2 Cells D006801:Humans D051379:Mice D008819:Mice, Nude D010957:Plasmids D011092:Polyethylene Glycols
Gene delivery system Nuclear locating sequence Gene transfection Lysosomal escape Tumor targeting