Up-regulation of miR-182 by β-catenin in breast cancer increases tumorigenicity and invasiveness by targeting the matrix metalloproteinase inhibitor RECK

Biochim Biophys Acta. 2013 Apr;1830(4):3067-76. doi: 10.1016/j.bbagen.2013.01.009. Epub 2013 Jan 16.

Abstract

Background: MiR-182 is a member of the miR-183 cluster located at human chromosome 7q32 region and is up-regulated in human cancers. We study the regulation of miR-182 expression and its oncogenic role.

Methods: MiR-182 level was investigated by real-time reverse transcription-PCR. Chromatin immunoprecipitation assay was used to confirm promoter binding of transcription factors. The correlation between miR-182 and RECK was analyzed by Western blotting, real-time RT-PCR and 3(')-untranslated region reporter assay. Zymography, matrix metalloproteinase activity, invasion and colony formation were used to study the tumorigenic activity.

Results: MiR-182 is over-expressed in human breast tumor tissues and cell lines. Inhibition or knockdown of β-catenin reduced miR-182 level in MDA-MB-231 cells. ChIP assay confirmed the binding of β-catenin on miR-182 promoter. Anti-miR-182 increased the MMP inhibitor RECK protein in MDA-MB-231 cells while pre-miR-182 reduced RECK protein but not mRNA in normal mammary epithelial H184B5F5/M10 cells. Restoration of RECK protein by anti-miR-182 attenuated MMP-9 activity, cell invasion and colony formation. Ectopic expression of miR-182 inhibited restoration of RECK protein by β-catenin inhibitor indicating miR-182 is important for β-catenin-induced down-regulation of RECK. An inverse association between miR-182 and RECK was demonstrated in breast tumor tissues.

Conclusions: We provide evidence that miR-182 is up-regulated by β-catenin signaling pathway in breast cancer and its up-regulation increases tumorigenicity and invasiveness by repressing RECK.

General significance: Our data demonstrate for the first time that miR-182 expression is controlled by β-catenin. In addition, we identify a new miR-182 target RECK which is important for miR-182-induced tumorigenesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Breast Neoplasms / etiology*
  • Breast Neoplasms / pathology
  • Cell Line, Tumor
  • Cell Transformation, Neoplastic*
  • Female
  • GPI-Linked Proteins / antagonists & inhibitors
  • GPI-Linked Proteins / physiology*
  • Humans
  • Matrix Metalloproteinase Inhibitors*
  • MicroRNAs / physiology*
  • Middle Aged
  • Neoplasm Invasiveness
  • Signal Transduction
  • Up-Regulation
  • beta Catenin / antagonists & inhibitors
  • beta Catenin / physiology*

Substances

  • CTNNB1 protein, human
  • GPI-Linked Proteins
  • Matrix Metalloproteinase Inhibitors
  • MicroRNAs
  • Mirn182 microRNA, human
  • RECK protein, human
  • beta Catenin