title: Key role of microRNA-15a in the KLF4 suppressions of proliferation and angiogenesis in endothelial and vascular smooth muscle cells.
abstract: While recent insights indicate that the transcription factor Krüppel-like factor 4 (KLF4) is indispensable for vascular homeostasis, its exact role in proliferation and angiogenesis and how it functions remain unresolved. Thus, the aim of the present study was to evaluate the role of KLF4 in the proliferations of endothelial and vascular smooth muscle cells, as well as the angiogenesis. The overexpression of KLF4 in endothelial cells significantly impaired tube formation. KLF4 inhibited the formation of a vascular network in implanted Matrigel plugs in nude mice. Importantly, we found that KLF4 significantly upregulated the miR-15a expression in endothelial cells and vascular smooth muscle cells, and conversely, KLF4 depletion reduced the amount of miR-15a. Furthermore, KLF4 blocked cell cycle progression and decreased cyclin D1 expression in endothelial cells and vascular smooth muscle cells through the induction of miR-15a. Intriguingly, the delivery of a miR-15a antagomir to nude mice resulted in marked attenuation of the anti-angiogenic effect of KLF4. Collectively, our present study provide the first evidence that miR-15a as a direct transcriptional target of KLF4 that mediates the anti-proliferative and anti-angiogenic actions of KLF4, which indicates that KLF4 upregulation of miR-15a may represent a therapeutic option to suppress proliferative vascular disorders.
authors.affiliation: Institute of Cardiovascular Science, Peking University Health Science Center, Beijing, China.
authors.forename: Xuemei
authors.initials: X
authors.lastname: Zheng
authors.forename: Aiqin
authors.initials: A
authors.lastname: Li
authors.forename: Liang
authors.initials: L
authors.lastname: Zhao
authors.forename: Tengfei
authors.initials: T
authors.lastname: Zhou
authors.forename: Qiang
authors.initials: Q
authors.lastname: Shen
authors.forename: Qinghua
authors.initials: Q
authors.lastname: Cui
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Qin
mesh_terms: D020413:3' Untranslated Regions; D000818:Animals; D002453:Cell Cycle; D049109:Cell Proliferation; D003094:Collagen / Q000737:chemistry; D019938:Cyclin D1 / Q000378:metabolism; D004338:Drug Combinations; D042783:Endothelial Cells / Q000166:cytology*; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D000090062:Kruppel-Like Factor 4; D051741:Kruppel-Like Transcription Factors / Q000378:metabolism*; D007797:Laminin / Q000737:chemistry; D051379:Mice; D008819:Mice, Nude; D035683:MicroRNAs / Q000378:metabolism*; D032389:Myocytes, Smooth Muscle / Q000166:cytology*; D009389:Neovascularization, Pathologic; D011509:Proteoglycans / Q000737:chemistry
chemical_list: D020413:3' Untranslated Regions; D004338:Drug Combinations; C000715467:KLF4 protein, human; C000715468:Klf4 protein, mouse; D000090062:Kruppel-Like Factor 4; D051741:Kruppel-Like Transcription Factors; D007797:Laminin; C505361:MIRN15 microRNA, human; D035683:MicroRNAs; D011509:Proteoglycans; C059485:matrigel; D019938:Cyclin D1; D003094:Collagen
keywords: 3′-UTRs; 3′-untranslated regions; BAECs; Cell cycle; ChIP; Cyclin D1; DMEM; Dulbecco’s modified Eagle’s medium; ECs; FBS; HE; HUVEC; KLF4; Krüppel-like factor 4; NC; Proliferation; RT-PCR; VE-Cad; VE-cadherin; VSMCs; bovine aortic endothelial cells; chromatin immunoprecipitation; endothelial cells; fetal bovine serum; hematoxylin eosin; human umbilical vein endothelial cell; krüppel-like factor 4; miR-15a; miRNA; microRNAs; negative control; reverse transcription polymerase chain reaction; vascular smooth muscle cells