title: microRNA miR-142-3p Inhibits Breast Cancer Cell Invasiveness by Synchronous Targeting of WASL, Integrin Alpha V, and Additional Cytoskeletal Elements.
abstract: MicroRNAs (miRNAs, micro ribonucleic acids) are pivotal post-transcriptional regulators of gene expression. These endogenous small non-coding RNAs play significant roles in tumorigenesis and tumor progression. miR-142-3p expression is dysregulated in several breast cancer subtypes. We aimed at investigating the role of miR-142-3p in breast cancer cell invasiveness. Supported by transcriptomic Affymetrix array analysis and confirmatory investigations at the mRNA and protein level, we demonstrate that overexpression of miR-142-3p in MDA-MB-231, MDA-MB-468 and MCF-7 breast cancer cells leads to downregulation of WASL (Wiskott-Aldrich syndrome-like, protein: N-WASP), Integrin-αV, RAC1, and CFL2, molecules implicated in cytoskeletal regulation and cell motility. ROCK2, IL6ST, KLF4, PGRMC2 and ADCY9 were identified as additional targets in a subset of cell lines. Decreased Matrigel invasiveness was associated with the miR-142-3p-induced expression changes. Confocal immunofluorescence microscopy, nanoscale atomic force microscopy and digital holographic microscopy revealed a change in cell morphology as well as a reduced cell volume and size. A more cortical actin distribution and a loss of membrane protrusions were observed in cells overexpressing miR-142-3p. Luciferase activation assays confirmed direct miR-142-3p-dependent regulation of the 3'-untranslated region of ITGAV and WASL. siRNA-mediated depletion of ITGAV and WASL resulted in a significant reduction of cellular invasiveness, highlighting the contribution of these factors to the miRNA-dependent invasion phenotype. While knockdown of WASL significantly reduced the number of membrane protrusions compared to controls, knockdown of ITGAV resulted in a decreased cell volume, indicating differential contributions of these factors to the miR-142-3p-induced phenotype. Our data identify WASL, ITGAV and several additional cytoskeleton-associated molecules as novel invasion-promoting targets of miR-142-3p in breast cancer.
authors.affiliation: Department of Gynecology and Obstetrics, Münster University Hospital, Münster, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Schwickert
authors.affiliation: Department of Gynecology and Obstetrics, Münster University Hospital, Münster, Germany.
authors.forename: Esther
authors.initials: E
authors.lastname: Weghake
authors.affiliation: Department of Gynecology and Obstetrics, Münster University Hospital, Münster, Germany.
authors.forename: Kathrin
authors.initials: K
authors.lastname: Brüggemann
authors.affiliation: Department of Gynecology and Obstetrics, Münster University Hospital, Münster, Germany.
authors.forename: Annika
authors.initials: A
authors.lastname: Engbers
authors.affiliation: Institute-associated Research Group "Cell adhesion and cell polarity", Institute of Medical Biochemistry, ZMBE, University of Münster, Münster, Germany.
authors.forename: Benjamin F
authors.initials: BF
authors.lastname: Brinkmann
authors.affiliation: Center for Biomedical Optics and Photonics, University of Muenster, Muenster, Germany.|Biomedical Technology Center, Medical Faculty, University of Münster, Münster, Germany.
authors.forename: Björn
authors.initials: B
authors.lastname: Kemper
authors.affiliation: Institute for Human Genetics, Medical Faculty of the University of Münster, Münster, Germany.
authors.forename: Jochen
authors.initials: J
authors.lastname: Seggewiß
authors.affiliation: Institute of Physiology II, University of Münster, Münster, Germany.|Department of Gastroenterology, Hepatology and Endocrinology, Hannover Medical School, Hannover, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Stock
authors.affiliation: Institute-associated Research Group "Cell adhesion and cell polarity", Institute of Medical Biochemistry, ZMBE, University of Münster, Münster, Germany.
authors.forename: Klaus
authors.initials: K
authors.lastname: Ebnet
authors.affiliation: Department of Gynecology and Obstetrics, Münster University Hospital, Münster, Germany.
authors.forename: Ludwig
authors.initials: L
authors.lastname: Kiesel
authors.affiliation: Center for Nanotechnology, Serend-ip GmbH, Münster, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Riethmüller
authors.affiliation: Department of Gynecology and Obstetrics, Münster University Hospital, Münster, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Götte
mesh_terms: D020413:3' Untranslated Regions; D000199:Actins / Q000378:metabolism; D001483:Base Sequence; D001943:Breast Neoplasms / Q000235:genetics / Q000473:pathology; D045744:Cell Line, Tumor; D002465:Cell Movement; D049109:Cell Proliferation; D048429:Cell Size; D003599:Cytoskeleton / Q000378:metabolism*; D015536:Down-Regulation; D005260:Female; D006801:Humans; D039564:Integrin alphaV / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D000090062:Kruppel-Like Factor 4; D061986:MCF-7 Cells; D035683:MicroRNAs / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000378:metabolism; D016415:Sequence Alignment; D051317:Wiskott-Aldrich Syndrome Protein, Neuronal / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*
chemical_list: D020413:3' Untranslated Regions; D000199:Actins; D039564:Integrin alphaV; C000715467:KLF4 protein, human; D000090062:Kruppel-Like Factor 4; C555159:MIRN142 microRNA, human; D035683:MicroRNAs; D034741:RNA, Small Interfering; C495771:WASL protein, human; D051317:Wiskott-Aldrich Syndrome Protein, Neuronal