title: Design of a targeted peptide nucleic acid prodrug to inhibit hepatic human microsomal triglyceride transfer protein expression in hepatocytes.
abstract: In this study, we present the design and synthesis of an antisense peptide nucleic acid (asPNA) prodrug, which displays an improved biodistribution profile and an equally improved capacity to reduce the levels of target mRNA. The prodrug, K(GalNAc)(2)-asPNA, comprised of a 14-mer sequence complementary to the human microsomal triglyceride transfer protein (huMTP) gene, conjugated to a high-affinity tag for the hepatic asialoglycoprotein receptor (K(GalNAc)(2)). The prodrug was avidly bound and rapidly internalized by HepG2s. After iv injection into mice, K(GalNAc)(2)-asPNA accumulated in the parenchymal liver cells to a much greater extent than nonconjugated PNA (46% +/- 1% vs 3.1% +/- 0.5% of the injected dose, respectively). The prodrug was able to reduce MTP mRNA levels in HepG2 cells by 35-40% (P < 0.02) at 100 nM in an asialoglycoprotein receptor- and sequence-dependent fashion. In conclusion, hepatocyte-targeted PNA prodrugs combine a greatly improved tropism with an enhanced local intracellular availability and activity, making them attractive therapeutics to lower the expression level of hepatic target genes such as MTP.
authors.affiliation: Division of Biopharmaceutics, Leiden/Amsterdam Center for Drug Research, Leiden University, P.O. Box 9503, 2300 RA Leiden, The Netherlands. biessen@LACDR.LeidenUniv.nl
authors.forename: Erik A L
authors.initials: EA
authors.lastname: Biessen
authors.forename: Karen
authors.initials: K
authors.lastname: Sliedregt-Bol
authors.forename: Peter A Chr
authors.initials: PA
authors.lastname: 'T Hoen
authors.forename: Perry
authors.initials: P
authors.lastname: Prince
authors.forename: Erica
authors.initials: E
authors.lastname: Van der Bilt
authors.forename: A Rob P M
authors.initials: AR
authors.lastname: Valentijn
authors.forename: Nico J
authors.initials: NJ
authors.lastname: Meeuwenoord
authors.forename: Hans
authors.initials: H
authors.lastname: Princen
authors.forename: Martin K
authors.initials: MK
authors.lastname: Bijsterbosch
authors.forename: Gijs A
authors.initials: GA
authors.lastname: Van der Marel
authors.forename: Jacques H
authors.initials: JH
authors.lastname: Van Boom
authors.forename: Theo J C
authors.initials: TJ
authors.lastname: Van Berkel
mesh_terms: D000818:Animals; D001212:Asialoglycoproteins / Q000494:pharmacology; D001483:Base Sequence; D001692:Biological Transport / Q000187:drug effects; D002352:Carrier Proteins / Q000235:genetics*; D002478:Cells, Cultured; D016503:Drug Delivery Systems; D015195:Drug Design; D060748:Fetuins; D005786:Gene Expression Regulation / Q000187:drug effects*; D022781:Hepatocytes / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D051379:Mice; D008810:Mice, Inbred C57BL; D008862:Microsomes, Liver / Q000187:drug effects / Q000378:metabolism; D015394:Molecular Structure; D020135:Peptide Nucleic Acids / Q000138:chemical synthesis* / Q000737:chemistry / Q000235:genetics / Q000494:pharmacology*; D011355:Prodrugs / Q000138:chemical synthesis* / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D014407:Tumor Cells, Cultured; D000509:alpha-Fetoproteins / Q000494:pharmacology
chemical_list: D001212:Asialoglycoproteins; D002352:Carrier Proteins; D060748:Fetuins; D020135:Peptide Nucleic Acids; D011355:Prodrugs; D012333:RNA, Messenger; D000509:alpha-Fetoproteins; C017029:asialofetuin; C106092:microsomal triglyceride transfer protein