title: MicroRNA MiR-199a-5p regulates smooth muscle cell proliferation and morphology by targeting WNT2 signaling pathway.
abstract: MicroRNA miR-199a-5p impairs tight junction formation, leading to increased urothelial permeability in bladder pain syndrome. Now, using transcriptome analysis in urothelial TEU-2 cells, we implicate it in the regulation of cell cycle, cytoskeleton remodeling, TGF, and WNT signaling pathways. MiR-199a-5p is highly expressed in the smooth muscle layer of the bladder, and we altered its levels in bladder smooth muscle cells (SMCs) to validate the pathway analysis. Inhibition of miR-199a-5p with antimiR increased SMC proliferation, reduced cell size, and up-regulated miR-199a-5p targets, including WNT2. Overexpression of WNT2 protein or treating SMCs with recombinant WNT2 closely mimicked the miR-199a-5p inhibition, whereas down-regulation of WNT2 in antimiR-expressing SMCs with shRNA restored cell phenotype and proliferation rates. Overexpression of miR-199a-5p in the bladder SMCs significantly increased cell size and up-regulated SM22, SM α-actin, and SM myosin heavy chain mRNA and protein levels. These changes as well as increased expression of ACTG2, TGFB1I1, and CDKN1A were mediated by up-regulation of the smooth muscle-specific transcriptional activator myocardin at mRNA and protein levels. Myocardin-related transcription factor A downstream targets Id3 and MYL9 were also induced. Up-regulation of myocardin was accompanied by down-regulation of WNT-dependent inhibitory Krüppel-like transcription factor 4 in miR-199a-5p-overexpressing cells. In contrast, Krüppel-like transcription factor 4 was induced in antimiR-expressing cells following the activation of WNT2 signaling, leading to repression of myocardin-dependent genes. MiR-199a-5p plays a critical role in the WNT2-mediated regulation of proliferative and differentiation processes in the smooth muscle and may behave as a key modulator of smooth muscle hypertrophy, which is relevant for organ remodeling.
authors.affiliation: From the Urology Research Laboratory, Department Clinical Research, University of Bern, 3010 Bern, Switzerland.
authors.forename: Ali
authors.initials: A
authors.lastname: Hashemi Gheinani
authors.affiliation: Department of Urology, University Hospital, 3010 Bern, Switzerland, and.
authors.forename: Fiona C
authors.initials: FC
authors.lastname: Burkhard
authors.affiliation: Functional Genomics Center Zurich, 8057 Zurich, Switzerland.
authors.forename: Hubert
authors.initials: H
authors.lastname: Rehrauer
authors.affiliation: Functional Genomics Center Zurich, 8057 Zurich, Switzerland.
authors.forename: Catharine
authors.initials: C
authors.lastname: Aquino Fournier
authors.affiliation: From the Urology Research Laboratory, Department Clinical Research, University of Bern, 3010 Bern, Switzerland, monastyk@dkf.unibe.ch.
authors.forename: Katia
authors.initials: K
authors.lastname: Monastyrskaya
mesh_terms: D002453:Cell Cycle; D002454:Cell Differentiation; D002460:Cell Line; D049109:Cell Proliferation; D048429:Cell Size; D015536:Down-Regulation; D005786:Gene Expression Regulation; D006801:Humans; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D032389:Myocytes, Smooth Muscle / Q000166:cytology* / Q000378:metabolism; D009687:Nuclear Proteins / Q000378:metabolism*; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics; D015534:Trans-Activators / Q000378:metabolism*; D015854:Up-Regulation; D001743:Urinary Bladder / Q000166:cytology / Q000378:metabolism; D019459:Urothelium / Q000166:cytology / Q000378:metabolism; D060449:Wnt Signaling Pathway; D051154:Wnt2 Protein / Q000235:genetics / Q000378:metabolism*; D000099251:Myocardin
chemical_list: D035683:MicroRNAs; D009687:Nuclear Proteins; D034741:RNA, Small Interfering; D015534:Trans-Activators; D051154:Wnt2 Protein; D000099251:Myocardin; C495244:WNT2 protein, human; C531408:mirn199 microRNA, human
keywords: Cell Proliferation; Differentiation; Gene Expression; MicroRNA (miRNA); Smooth Muscle; WNT Signaling