Efficient gene delivery to oral cancer cells by polyethylenimine-DNA complexes
Nejat Düzgüneş: 0000-0001-6159-1391
39th Annual Meeting of the American Association for Dental Research (AADR)
March 3-6, 2010
Date of Presentation
Journal of Dental Research
Journal Volume Number
89 (Special issue A)
Objective: One of the problems in the use of cationic-lipid-DNA complexes (lipoplexes) for gene therapy of oral squamous cell carcinoma (OSCC) is the low efficiency of transfection of OSCC cell, and its variability from one cell type to another. Cationic polymer-DNA complexes (polyplexes) are internalized via caveolae, instead of coated pits as in the case with lipoplexes. We therefore tested whether polyplexes mediate efficient gene delivery to various human OSCC cells. Methods: HSC-3, H413 and H357 cells were seeded the day before transfection, and used at 85% or 50% confluence. The plasmid pCMV.luc (1 µg DNA) expressing luciferase under the control of the cytomegalovirus promoter was complexed with 1, 2 or 4 µl of the cationic polyethylenimine, jetPEI (Polyplus transfection). The plasmid was also complexed with a cationic lipid transfection reagent, Metafectene (Biontex) (1 µg DNA/2 µl Metafectene). Luciferase expression was assayed 48 h after transfection. Results: The efficiency of transfection with jetPEI polyplexes was much higher than that obtained with lipoplexes, and higher gene expression was observed at 50% confluence compared to that at 85% confluence with all three cell lines. For example, in lipofection-resitant H357 cells at 50% confluence, the use of 1, 2 or 4 µl jetPEI resulted in a 922-, 1081- and 1440-fold increase, respectively, in luciferase activity over that obtained with Metafectene. At 85% confluence, polyplexes enhanced gene expression by 149-, 252- and 545-fold at jetPEI volumes of 1, 2 and 4 µl, respectively. Conclusion: Cell density is a significant variable in efficient transfection of OSCC cells. The use of polyplexes instead of lipoplexes can drastically increase transfection efficiency in OSCC cells. Our laboratory is currently investigating whether jetPEI-DNA complexes are internalized by caveolae. Funded by an AADR Student Research Fellowship and a Research Pilot Project Award from the Dugoni School of Dentistry (JF).
Efficient gene delivery to oral cancer cells by polyethylenimine-DNA complexes.
Paper presented at 39th Annual Meeting of the American Association for Dental Research (AADR) in Washington, DC.