Gene therapy in colon cancer cells with a fiber-modified adenovector expressing the TRAIL gene driven by the hTERT promoter.
BACKGROUND
Repeated administration of adenoviral vectors can lead to cell resistance, probably because of the initial coxsackie-adenovirus receptor (CAR). Modified adenoviral vectors containing an Arg-Gly-Asp (RGD) sequence can overcome resistance. 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 tested its antitumor activity in 5 colon carcinoma cell lines.


METHODS
Colon cancer cells were infected with Ad/CMV-GFP (vector control), Ad/gTRAIL (positive control) and Ad/TRAIL-FIRGD. PBS was used as a control. Cell viability was determined by proliferation assay. Cell-cycle analysis and quantification of Caspase-8 and TRAIL were used to identify apoptosis.


RESULTS
Treatment with Ad/TRAIL-F/RGD resulted in significantly less cell viability, increased Caspase-8 and TRAIL activity, and a greater apoptotic fraction than treatment with PBS or Ad/CMV-GFP.


CONCLUSIONS
The adenoviral vector Ad/TRAIL-F/RGD could become a potent therapeutic agent for the treatment of colon carcinoma.
Jacob
Dietmar
D
Department of General, Visceral and Transplantation Surgery, Humboldt University of Berlin, Charité Campus-Virchow, Berlin, Germany. dietmar.jacob@charite.de
Bahra
Marcus
M
Schumacher
Guido
G
Neuhaus
Peter
P
Fang
Bingliang
B
D000260:Adenoviruses, Human / Q000235:genetics*; D017209:Apoptosis / Q000235:genetics; D051017:Apoptosis Regulatory Proteins; D053181:Caspase 8; D020169:Caspases / Q000378:metabolism; D045744:Cell Line, Tumor; D003110:Colonic Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology / Q000628:therapy*; D004268:DNA-Binding Proteins; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors / Q000235:genetics; D049452:Green Fluorescent Proteins / Q000096:biosynthesis / Q000235:genetics; D006801:Humans; D008562:Membrane Glycoproteins / Q000096:biosynthesis / Q000235:genetics*; D009842:Oligopeptides / Q000235:genetics; D011401:Promoter Regions, Genetic; D053221:TNF-Related Apoptosis-Inducing Ligand; D019098:Telomerase / Q000235:genetics*; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis / Q000235:genetics*
D051017:Apoptosis Regulatory Proteins; D004268:DNA-Binding Proteins; D008562:Membrane Glycoproteins; D009842:Oligopeptides; D053221:TNF-Related Apoptosis-Inducing Ligand; C505653:TNFSF10 protein, human; D014409:Tumor Necrosis Factor-alpha; D049452:Green Fluorescent Proteins; C047981:arginyl-glycyl-aspartic acid; D019098:Telomerase; C505530:CASP8 protein, human; D053181:Caspase 8; D020169:Caspases