title: Systemically delivered antisense oligomers upregulate gene expression in mouse tissues.
abstract: Systemically injected 2'-O-methoxyethyl (2'-O-MOE)-phosphorothioate and PNA-4K oligomers (peptide nucleic acid with four lysines linked at the C terminus) exhibited sequence-specific antisense activity in a number of mouse organs. Morpholino oligomers were less effective, whereas PNA oligomers with only one lysine (PNA-1K) were completely inactive. The latter result indicates that the four-lysine tail is essential for the antisense activity of PNA oligomers in vivo. These results were obtained in a transgenic mouse model designed as a positive readout test for activity, delivery, and distribution of antisense oligomers. In this model, the expressed gene (EGFP-654) encoding enhanced green fluorescence protein (EGFP) is interrupted by an aberrantly spliced mutated intron of the human beta-globin gene. Aberrant splicing of this intron prevented expression of EGFP-654 in all tissues, whereas in tissues and organs that took up a splice site-targeted antisense oligomer, correct splicing was restored and EGFP-654 expression upregulated. The sequence-specific ability of PNA-4K and the 2'-O-MOE oligomers to upregulate EGFP-654 provides strong evidence that systemically delivered, chemically modified oligonucleotides affect gene expression by sequence-specific true antisense activity, validating their application as potential therapeutics.
authors.affiliation: Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, USA.
authors.forename: Peter
authors.initials: P
authors.lastname: Sazani
authors.forename: Federica
authors.initials: F
authors.lastname: Gemignani
authors.forename: Shin-Hong
authors.initials: SH
authors.lastname: Kang
authors.forename: Martin A
authors.initials: MA
authors.lastname: Maier
authors.forename: Muthiah
authors.initials: M
authors.lastname: Manoharan
authors.forename: Magnus
authors.initials: M
authors.lastname: Persmark
authors.forename: Donna
authors.initials: D
authors.lastname: Bortner
authors.forename: Ryszard
authors.initials: R
authors.lastname: Kole
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D005347:Fibroblasts / Q000187:drug effects / Q000502:physiology*; D005786:Gene Expression Regulation / Q000187:drug effects*; D015316:Genetic Therapy / Q000379:methods; D007275:Injections, Intravenous; D008099:Liver / Q000187:drug effects / Q000502:physiology*; D051379:Mice; D008822:Mice, Transgenic; D016376:Oligonucleotides, Antisense / Q000008:administration & dosage* / Q000493:pharmacokinetics; D009928:Organ Specificity; D020135:Peptide Nucleic Acids / Q000008:administration & dosage / Q000493:pharmacokinetics; D014018:Tissue Distribution; D015854:Up-Regulation / Q000187:drug effects
chemical_list: D016376:Oligonucleotides, Antisense; D020135:Peptide Nucleic Acids