title: Enhanced gene expression in tumors after intravenous administration of arginine-, lysine- and leucine-bearing polyethylenimine polyplex.
abstract: The potential of gene therapy to treat cancer is currently limited by the low expression of therapeutic genes in the tumors. Because amino acids are known to have excellent properties in cell penetration and gene expression regulation, we investigated if the conjugation of arginine (Arg), lysine (Lys) and leucine (Leu) onto the surface of the gene delivery system polyethylenimine (PEI) could lead to an improved gene expression in tumors. The intravenous administration of Arg-, Lys- and Leu-bearing PEI polyplexes led to a significant increase of gene expression in the tumor, with a β-galactosidase expression amount at least threefold higher than that obtained after treatment with unmodified PEI polyplex. The three amino acid-bearing PEI polyplexes led to similar levels of gene expression in the tumor. The treatments were well tolerated by the mice. Arg-, Lys- and Leu-bearing PEI polyplexes are therefore highly promising gene delivery systems for cancer therapy.
authors.affiliation: Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom.
authors.forename: Hibah
authors.initials: H
authors.lastname: Aldawsari
authors.forename: Behin Sundara
authors.initials: BS
authors.lastname: Raj
authors.forename: RuAngelie
authors.initials: R
authors.lastname: Edrada-Ebel
authors.forename: David R
authors.initials: DR
authors.lastname: Blatchford
authors.forename: Rothwelle J
authors.initials: RJ
authors.lastname: Tate
authors.forename: Laurence
authors.initials: L
authors.lastname: Tetley
authors.forename: Christine
authors.initials: C
authors.lastname: Dufès
mesh_terms: D000818:Animals; D001120:Arginine / Q000008:administration & dosage* / Q000737:chemistry; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects*; D018014:Gene Transfer Techniques; D015316:Genetic Therapy / Q000379:methods*; D006801:Humans; D007930:Leucine / Q000008:administration & dosage* / Q000737:chemistry; D008239:Lysine / Q000008:administration & dosage* / Q000737:chemistry; D051379:Mice; D008807:Mice, Inbred BALB C; D009369:Neoplasms / Q000628:therapy*; D011094:Polyethyleneimine / Q000737:chemistry*; D001616:beta-Galactosidase / Q000187:drug effects / Q000235:genetics
chemical_list: D011094:Polyethyleneimine; D001120:Arginine; D001616:beta-Galactosidase; D007930:Leucine; D008239:Lysine