title: Antisense inhibition of Flk-1 by oligonucleotides composed of 2'-deoxy-2'-fluoro-beta-D-arabino- and 2'-deoxy-nucleosides.
abstract: The design of new antisense oligomers with improved binding affinity for targeted RNA, while still activating RNase H, is a major research area in medicinal chemistry. RNase H recognizes the RNA-DNA duplex and cleaves the complementary mRNA strand, providing the main mechanism by which antisense oligomers elicit their activities. It has been shown that configuration inversion at the C2' position of the DNA sugar moiety (arabinonucleic acid, ANA), combined with the substitution of the 2'OH group by a fluorine atom (2'F-ANA) increases the oligomer's binding affinity for targeted RNA. In the present study, we evaluated the antisense activity of mixed-backbone phosphorothioate oligomers composed of 2'-deoxy-2'-fluoro-beta-D-arabinose and 2'-deoxyribose sugars (S-2'F-ANA-DNA chimeras). We determined their abilities to inhibit the protein expression and phosphorylation of Flk-1, a vascular endothelial growth factor receptor (VEGF), and VEGF biological effects on endothelial cell proliferation, migration, and platelet-activating factor synthesis. Treatment of endothelial cells with chimeric oligonucleotides reduced Flk-1 protein expression and phosphorylation more efficiently than with phosphorothioate antisenses (S-DNA). Nonetheless, these two classes of antisenses inhibited VEGF activities equally. Herein, we also demonstrated the capacity of the chimeric oligomers to elicit RNase H activity and their improved binding affinity for complementary RNA as compared with S-DNA.
authors.forename: Julie
authors.initials: J
authors.lastname: Lacombe
authors.forename: Ekaterina
authors.initials: E
authors.lastname: Viazovkina
authors.forename: Pascal N
authors.initials: PN
authors.lastname: Bernatchez
authors.forename: Annie
authors.initials: A
authors.lastname: Galarneau
authors.forename: Masad J
authors.initials: MJ
authors.lastname: Damha
authors.forename: Martin G
authors.initials: MG
authors.lastname: Sirois
mesh_terms: D000818:Animals; D001011:Aorta / Q000166:cytology / Q000187:drug effects; D001087:Arabinonucleosides / Q000737:chemistry*; D002417:Cattle; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D002633:Chemotaxis / Q000187:drug effects; D016228:Endothelial Growth Factors / Q000494:pharmacology; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000494:pharmacology; D008222:Lymphokines / Q000494:pharmacology; D020319:Oligodeoxyribonucleotides, Antisense / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D010766:Phosphorylation; D010972:Platelet Activating Factor / Q000096:biosynthesis; D016914:Ribonuclease H / Q000378:metabolism; D042461:Vascular Endothelial Growth Factor A; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000037:antagonists & inhibitors* / Q000378:metabolism; D042442:Vascular Endothelial Growth Factors
chemical_list: D001087:Arabinonucleosides; D016228:Endothelial Growth Factors; D036341:Intercellular Signaling Peptides and Proteins; D008222:Lymphokines; D020319:Oligodeoxyribonucleotides, Antisense; D010972:Platelet Activating Factor; D042461:Vascular Endothelial Growth Factor A; D042442:Vascular Endothelial Growth Factors; D040301:Vascular Endothelial Growth Factor Receptor-2; D016914:Ribonuclease H