title: Tumor-specific gene delivery mediated by a novel peptide-polyethylenimine-DNA polyplex targeting aminopeptidase N/CD13.
abstract: We have developed a novel polyethylenimine (PEI)-DNA vector formulation that is capable of efficient tumor-specific delivery after intravenous administration to nude mice. To further increase the specificity of delivery, we have attached the peptide CNGRC to the vector, which is specific for aminopeptidase N (CD13). The strategy for coupling this peptide to PEI was based on a novel method involving the strong affinity between phenyl(di)boronic acid (PDBA) and salicylhydroxamic acid (SHA) as well as a polyethylene glycol (PEG) linker to reduce steric hindrance between the vector and the peptide. In vitro assessment of targeting by the CNGRC/PEG/PEI/DNA vector carrying a beta-galactosidase (beta-Gal)-expressing plasmid showed as much as a 5-fold increase in transduction, relative to the untargeted PEG/PEI/DNA-betagal vector, of CD13-positive lung cancer, fibrosarcoma, bladder cancer, and human umbilical vein endothelial cells. Competition with free peptide resulted in up to a 90% reduction in delivery, indicating that gene delivery was specific for CD13-positive cells. Intravenous administration of the CNGRC/PEG/PEI/DNA-betagal vector to nude mice bearing subcutaneous tumors resulted in as much as a 12-fold increase in beta-Gal expression in tumors as compared with expression in either lungs or tumors from animals treated with the original PEI/DNA-betagal vector. In vivo transduction analysis using the CNGRC/PEG/PEI/DNA vector to target the intravenous delivery of a yellow fluorescence protein (YFP)-expressing plasmid to subcutaneous H1299 tumors confirmed delivery of YFP to both tumor cells and tumor endothelial cells. The use of this peptide to further increase tumor-specific delivery mediated by our novel PEI/DNA vector now provides a basis for developing tumor-targeted gene therapies for use in the clinical treatment of cancer.
authors.affiliation: Department of Genitourinary Medical Oncology, University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA.
authors.forename: Stanley
authors.initials: S
authors.lastname: Moffatt
authors.forename: Sandra
authors.initials: S
authors.lastname: Wiehle
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Cristiano
mesh_terms: D000818:Animals; D018826:CD13 Antigens / Q000008:administration & dosage / Q000378:metabolism / Q000627:therapeutic use*; D002478:Cells, Cultured; D004247:DNA / Q000008:administration & dosage*; D016503:Drug Delivery Systems; D042783:Endothelial Cells / Q000378:metabolism; D005260:Female; D005354:Fibrosarcoma / Q000235:genetics / Q000378:metabolism / Q000628:therapy; D018390:Gene Targeting; D005822:Genetic Vectors / Q000627:therapeutic use; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics / Q000378:metabolism / Q000628:therapy; D051379:Mice; D008819:Mice, Nude; D009842:Oligopeptides / Q000378:metabolism / Q000494:pharmacology*; D011092:Polyethylene Glycols / Q000737:chemistry / Q000494:pharmacology; D011094:Polyethyleneimine / Q000008:administration & dosage*; D014161:Transduction, Genetic; D014471:Umbilical Veins / Q000378:metabolism; D001749:Urinary Bladder Neoplasms / Q000235:genetics / Q000378:metabolism / Q000628:therapy; D001616:beta-Galactosidase / Q000378:metabolism
chemical_list: D009842:Oligopeptides; D011092:Polyethylene Glycols; D011094:Polyethyleneimine; D004247:DNA; D001616:beta-Galactosidase; D018826:CD13 Antigens