Objective: To evaluate the killing effects of the cytosine deaminase (CD) gene mediated by adenovirus vector on human pancreatic cancer cell lines in vitro.
Methods: The CD gene was cloned into pAdTrack-CMV-CD, and pAdTrack-CMV-CD and pAdEasy-1 were recombinated in bacteria. The newly recombinated Ad-CD containing green fluorescent protein (GFP) was propagated in 293 cells and purified by cesium chloride gradient centrifugation. Human pancreatic cancer cell lines Patu8988 and SW1990 were infected with this virus, then 5-FC was added. XTT assay was used to estimate relative numbers of viable cells.
Results: The positive clones were selected by using endonuclease to digest the combinatants and the concentration of viral liquids containing the CD gene was 2X10(11) pfu/ml. It was found that significant cytotoxic activities were possessed by 5-FC for the CD gene transduced pancreatic cell lines, but little effects exerted on the nontransduced pancreatic carcinoma cells.
Conclusions: The CD gene mediated by adenovirus with a high infectivity is efficient for gene therapy of pancreatic carcinoma cell lines. These data demonstrate the therapeutic efficacy of an enzyme prodrug strategy in experimental pancreatic cancer.