Gentherapie durch einen RGD-modifizierten, hTERT-regulierten, TRAIL-exprimierenden adenoviralen vektor in malignen tumoren

Background: Resistance can be overcome by modified adenoviral vectors containing an Arg-Gly-Asp (RGD) sequence. We constructed an adenoviral vector with RGD-modified fibers, expressing the TRAIL gene from the human telomerase reverse transcriptase (hTERT) promoter (designated Ad/TRAIL-F/RGD), and evaluated its antitumor activity in vitro and in vivo. Methods: The induction of apoptosis by the new vector Ad/TRAIL-F/RGD was evaluated in human carcinoma cells derived from hepatocellular carcinoma (Hep G2, Hep 3b), pancreatic carcinoma (Panc-1, Capan-1), and colon carcinoma (LOVO, SW 620). Cell viability was measured by the XTT assay and GFP expression and apoptosis induction by fluorescence-activated cell sorting (FACS) and Western blot. In vivo experiments were performed in an orthotopic pancreas tumor model in nu/nu nude mice. Results: Treatment with Ad/TRAIL-F/RGD and Ad/gTRAIL resulted in significantly reduced cell viability in comparison to PBS and Ad/CMV-GFP treatment in all examined human carcinoma cell lines. In addition, mice treated with Ad/TRAIL-F/RGD showed a significantly decreased tumor growth than both control groups. Conclusions: Our results suggest that Ad/TRAIL-F/RGD may become a potent therapeutic agent for the treatment of different human solid carcinomas.