title: Effect of microRNA-206 on cytoskeleton remodelling by downregulating Cdc42 in MDA-MB-231 cells.
abstract: OBJECTIVE
  MicroRNAs are small, noncoding, single-stranded RNAs that regulate gene expression post-transcriptionally. miR-206 is known to play an important role in breast cancer metastasis. When we sought to predict the target of miR-206 by Targetscan, Pictar and miRanda, we found Cdc42 was a potential one. In this study, we transfected miR-206 into MDA-MB-231 cells and examined Cdc42 protein expression as well as MMP-2 and MMP-9, which are also associated with metastasis of breast cancer. Since Cdc42 is involved in filopodia and invadopodia formation, we examined the morphological changes of MDA-MB-231 cells.
  
  
  METHODS
  miR-206 mimics were transfected into MDA-MB-231 cells using LipofectamineTM 2000. Protein expression was detected by Western blot. Cells were stained with FITC-phalloidin to visualize F-actin. Invasive ability and migratory ability were examined by invasion assay and migration assay in vitro.
  
  
  RESULTS
  Cdc42, MMP-2 and MMP-9 were downregulated on the protein level. The formation of filopodia, which requires Cdc42, was inhibited in miR-206 transfected cells, even under the stimulation of EGF. The invasion and migration of MDA-MB-231 cells in vitro was inhibited by miR-206 too.
  
  
  CONCLUSIONS
  The results suggest that miR-206 may suppress invasion and migration of MDA-MB-231 cells in vitro partly via regulating actin cytoskeleton remodelling such as filopodia formation.
authors.affiliation: Department of Pathology Molecular Medicine and Cancer Research Center, Chongqing Medical University, Chongqing, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Liu
authors.forename: You-De
authors.initials: YD
authors.lastname: Cao
authors.forename: Wei-Xia
authors.initials: WX
authors.lastname: Ye
authors.forename: Yang-Yang
authors.initials: YY
authors.lastname: Sun
mesh_terms: D000199:Actins / Q000378:metabolism; D015153:Blotting, Western; D045744:Cell Line, Tumor; D002465:Cell Movement; D003599:Cytoskeleton / Q000235:genetics / Q000378:metabolism*; D015536:Down-Regulation; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism; D035683:MicroRNAs / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D016133:Polymerase Chain Reaction; D014162:Transfection; D020764:cdc42 GTP-Binding Protein / Q000378:metabolism*
chemical_list: D000199:Actins; C546087:MIRN206 microRNA, human; D035683:MicroRNAs; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9; D020764:cdc42 GTP-Binding Protein