microRNA miR-142-3p Inhibits Breast Cancer Cell Invasiveness by Synchronous Targeting of WASL, Integrin Alpha V, and Additional Cytoskeletal Elements

PLoS One. 2015 Dec 10;10(12):e0143993. doi: 10.1371/journal.pone.0143993. eCollection 2015.

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3' Untranslated Regions
  • Actins / metabolism
  • Base Sequence
  • Breast Neoplasms / genetics
  • Breast Neoplasms / pathology
  • Cell Line, Tumor
  • Cell Movement
  • Cell Proliferation
  • Cell Size
  • Cytoskeleton / metabolism*
  • Down-Regulation
  • Female
  • Humans
  • Integrin alphaV / chemistry
  • Integrin alphaV / genetics
  • Integrin alphaV / metabolism*
  • Kruppel-Like Factor 4
  • MCF-7 Cells
  • MicroRNAs / chemistry
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • RNA Interference
  • RNA, Small Interfering / metabolism
  • Sequence Alignment
  • Wiskott-Aldrich Syndrome Protein, Neuronal / antagonists & inhibitors
  • Wiskott-Aldrich Syndrome Protein, Neuronal / genetics
  • Wiskott-Aldrich Syndrome Protein, Neuronal / metabolism*

Substances

  • 3' Untranslated Regions
  • Actins
  • Integrin alphaV
  • KLF4 protein, human
  • Kruppel-Like Factor 4
  • MIRN142 microRNA, human
  • MicroRNAs
  • RNA, Small Interfering
  • WASL protein, human
  • Wiskott-Aldrich Syndrome Protein, Neuronal

Grant support

This study was funded by Innovative Medizinische Forschung (IMF), Medical Faculty Münster University, grant number I-Gö 111110, URL: http://campus.uni-muenster.de/imf.html; IZKF, Medical Faculty Münster University, grant numberIZKF Eb2/020/14, URL: http://campus.uni-muenster.de/izkf.html; BMBF grants FKZ13N10937 and 01DJ130022A; URL: http://www.bmbf.de/en/index.php; Open Access Publication Fund of University of Muenster (no grant number); URL: http://www.uni-muenster.de/Publizieren/service/publikationsfonds/; EU H2020 RISE-MSCA Project grant number 645756 (GLYCANC) URL: http://cordis.europa.eu/search/result_en?q=GLYCANC&searchType=simple. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.