MiR-200 can repress breast cancer metastasis through ZEB1-independent but moesin-dependent pathways

Oncogene. 2014 Jul 31;33(31):4077-88. doi: 10.1038/onc.2013.370. Epub 2013 Sep 16.

Abstract

The microRNA-200 (miR-200) family has a critical role in regulating epithelial-mesenchymal transition and cancer cell invasion through inhibition of the E-cadherin transcriptional repressors ZEB1 and ZEB2. Recent studies have indicated that the miR-200 family may exert their effects at distinct stages in the metastatic process, with an overall effect of enhancing metastasis in a syngeneic mouse breast cancer model. We find in a xenograft orthotopic model of breast cancer metastasis that ectopic expression of members of the miR-200b/200c/429, but not the miR-141/200a, functional groups limits tumour cell invasion and metastasis. Despite modulation of the ZEB1-E-cadherin axis, restoration of ZEB1 in miR-200b-expressing cells was not able to alter metastatic potential suggesting that other targets contribute to this process. Instead, we found that miR-200b repressed several actin-associated genes, with the knockdown of the ezrin-radixin-moesin family member moesin alone phenocopying the repression of cell invasion by miR-200b. Moesin was verified to be directly targeted by miR-200b, and restoration of moesin in miR-200b-expressing cells was sufficient to alleviate metastatic repression. In breast cancer cell lines and patient samples, the expression of moesin significantly inversely correlated with miR-200 expression, and high levels of moesin were associated with poor relapse-free survival. These findings highlight the context-dependent effects of miR-200 in breast cancer metastasis and demonstrate the existence of a moesin-dependent pathway, distinct from the ZEB1-E-cadherin axis, through which miR-200 can regulate tumour cell plasticity and metastasis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Breast Neoplasms / genetics
  • Breast Neoplasms / metabolism*
  • Breast Neoplasms / pathology
  • Cadherins / metabolism
  • Cell Line, Tumor
  • Female
  • Gene Expression Regulation, Neoplastic
  • Gene Knockdown Techniques
  • Homeodomain Proteins / genetics
  • Homeodomain Proteins / metabolism
  • Humans
  • Lung Neoplasms / genetics
  • Lung Neoplasms / secondary
  • Mammary Neoplasms, Experimental
  • Mice
  • MicroRNAs / metabolism*
  • Microfilament Proteins / metabolism*
  • Neoplasm Invasiveness*
  • Repressor Proteins / genetics
  • Repressor Proteins / metabolism*
  • Signal Transduction*
  • Transcription Factors / genetics
  • Transcription Factors / metabolism
  • Zinc Finger E-box Binding Homeobox 2
  • Zinc Finger E-box-Binding Homeobox 1

Substances

  • Cadherins
  • Homeodomain Proteins
  • MIRN200 microRNA, human
  • MicroRNAs
  • Microfilament Proteins
  • Repressor Proteins
  • Transcription Factors
  • ZEB1 protein, human
  • ZEB2 protein, human
  • Zinc Finger E-box Binding Homeobox 2
  • Zinc Finger E-box-Binding Homeobox 1
  • moesin