Development of novel AAV serotype 6 based vectors with selective tropism for human cancer cells.
Viral vectors-based gene therapy is an attractive alternative to common anti-cancer treatments. In the present studies, AAV serotype 6 vectors were identified to be particularly effective in the transduction of human prostate (PC3), breast (T47D) and liver (Huh7) cancer cells. Next, we developed chimeric AAV vectors with Arg-Gly-Asp (RGD) peptide incorporated into the viral capsid to enable specific targeting of integrin-overexpressing malignant cells. These AAV6-RGD vectors improved transduction efficiency approximately 3-fold compared with wild-type AAV6 vectors by enhancing the viral entry into the cells. We also observed that transduction efficiency significantly improved, up to approximately 5-fold, by the mutagenesis of surface-exposed tyrosine and threonine residues involved in the intracellular trafficking of AAV vectors. Therefore, in our study, the AAV6-Y705-731F+T492V vector was identified as the most efficient. The combination of RGD peptide, tyrosine and threonine mutations on the same AAV6 capsid further increased the transduction efficiency, approximately 8-fold in vitro. In addition, we mutated lysine (K531E) to impair the affinity of AAV6 vectors to heparan sulfate proteoglycan. Finally, we showed a significant increase in both specificity and efficiency of AAV6-RGD-Y705-731F+T492V+K531E vectors in a xenograft animal model in vivo. In summary, the approach described here can lead to the development of AAV vectors with selective tropism to human cancer cells.
Department of Biology, University of Florida, College of Medicine, Gainesville, FL, USA.|Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida, College of Medicine, Gainesville, FL, USA.
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Sayroo
Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida, College of Medicine, Gainesville, FL, USA.|Department of Microbiology and Cell Science, University of Florida, College of Medicine, Gainesville, FL, USA.
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Nolasco
Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida, College of Medicine, Gainesville, FL, USA.
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Yin
Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida, College of Medicine, Gainesville, FL, USA.|Pulmonary Division, Department of Pediatrics, University of Florida, College of Medicine, Gainesville, FL, USA.
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Colon-Cortes
Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida, College of Medicine, Gainesville, FL, USA.|Department of Microbiology and Cell Science, University of Florida, College of Medicine, Gainesville, FL, USA.
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Pandya
Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida, College of Medicine, Gainesville, FL, USA.|Shands Cancer Center, University of Florida, College of Medicine, Gainesville, FL, USA.
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Ling
Division of Cellular and Molecular Therapy, Department of Pediatrics, University of Florida, College of Medicine, Gainesville, FL, USA.|Shands Cancer Center, University of Florida, College of Medicine, Gainesville, FL, USA.
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Aslanidi
D000818:Animals; D036022:Capsid Proteins / Q000235:genetics / Q000378:metabolism; D045744:Cell Line, Tumor; D000229:Dependovirus / Q000235:genetics*; D004195:Disease Models, Animal; D015316:Genetic Therapy; D005822:Genetic Vectors; D057809:HEK293 Cells; D022781:Hepatocytes / Q000378:metabolism; D006801:Humans; D008297:Male; D051379:Mice; D009369:Neoplasms / Q000628:therapy*; D009842:Oligopeptides / Q000235:genetics / Q000378:metabolism; D010957:Plasmids / Q000235:genetics; D011994:Recombinant Proteins / Q000235:genetics; D014161:Transduction, Genetic; D056189:Viral Tropism / Q000235:genetics*; D023041:Xenograft Model Antitumor Assays
D036022:Capsid Proteins; D009842:Oligopeptides; D011994:Recombinant Proteins; C047981:arginyl-glycyl-aspartic acid