Targeting gene transfer vectors to oral squamous cell carcinoma cells
Nejat Düzgüneş: 0000-0001-6159-1391
85th General Session of the International Association for Dental Research (IADR) and 36rd Annual Meeting of the American Association for Dental Research (AADR)
New Orleans, LA
March 21-24, 2007
Date of Presentation
Journal of Dental Research
Journal Volume Number
86 (Special issue A)
Squamous cell carcinoma (SSC) of the head and neck causes approximately 11,000 deaths/year in the US. Cytotoxic gene therapy approaches may be able to target cancer cells specifically, while sparing normal cells. Objectives: Since SCC cells overexpress the receptor for Epidermal Growth Factor (EGF), we tested the hypothesis that targeting non-viral gene delivery vectors to EGF receptors would increase reporter gene expression in these cells. Methods: Murine SCC VII and non-tumor-derived NIH-3T3 cells, and human KB epidermoid carcinoma and non-tumor GMSM-K oral keratinocytes were seeded in 48-well culture plates, and used at about 80% confluence 24 h later. The pCMV.Luc plasmid expressing luciferase was complexed with cationic liposomes (DOTAP:cholesterol; 1:1) with or without recombinant epidermal growth factor, forming “lipoplexes,” which were incubated with the cells for 4 h and then removed. Luciferase activity was determined after 48 h, using the Promega Luciferase Assay System. Results: In KB cells, complexation of 5 µg EGF with lipoplexes increased luciferase activity from 5,000±1700 to 71,000±4,800 relative light units (RLU)/ml, a 14-fold increase, while In GMSM-K cells, the increase was only 3-fold. In SCCVII cells, luciferase expression increased from 6,500±1,800 RLU/ml for controls to 718,000±80,000 RLU/ml with EGF-lipoplexes, a 109-fold increase. In NIH-3T3 cells gene expression increased by only 7-fold with EGF, and was much lower than that in SCCVII cells. The gene expression ratio SCC VII/NIH-3T3 was 115. Conclusions: The use of EGF-lipoplexes facilitated greater transfer of reporter genes to cancer cells. This differential expression is likely to be useful in “suicide” gene therapy of oral SCC (Supported by a Research Pilot Project Award 03-Activity 041 from the Arthur A. Dugoni School of Dentistry to A. Streeter).
Targeting gene transfer vectors to oral squamous cell carcinoma cells.
Paper presented at 85th General Session of the International Association for Dental Research (IADR) and 36rd Annual Meeting of the American Association for Dental Research (AADR) in New Orleans, LA.