title: The miR-200 family and miR-205 regulate epithelial to mesenchymal transition by targeting ZEB1 and SIP1.
abstract: Epithelial to mesenchymal transition (EMT) facilitates tissue remodelling during embryonic development and is viewed as an essential early step in tumour metastasis. We found that all five members of the microRNA-200 family (miR-200a, miR-200b, miR-200c, miR-141 and miR-429) and miR-205 were markedly downregulated in cells that had undergone EMT in response to transforming growth factor (TGF)-beta or to ectopic expression of the protein tyrosine phosphatase Pez. Enforced expression of the miR-200 family alone was sufficient to prevent TGF-beta-induced EMT. Together, these microRNAs cooperatively regulate expression of the E-cadherin transcriptional repressors ZEB1 (also known as deltaEF1) and SIP1 (also known as ZEB2), factors previously implicated in EMT and tumour metastasis. Inhibition of the microRNAs was sufficient to induce EMT in a process requiring upregulation of ZEB1 and/or SIP1. Conversely, ectopic expression of these microRNAs in mesenchymal cells initiated mesenchymal to epithelial transition (MET). Consistent with their role in regulating EMT, expression of these microRNAs was found to be lost in invasive breast cancer cell lines with mesenchymal phenotype. Expression of the miR-200 family was also lost in regions of metaplastic breast cancer specimens lacking E-cadherin. These data suggest that downregulation of the microRNAs may be an important step in tumour progression.
authors: Hanson Institute and Division of Human Immunology, Institute of Medical and Veterinary Science, Adelaide, SA 5000, Australia.
authors: Philip A
authors: PA
authors: Gregory
authors: Andrew G
authors: AG
authors: Bert
authors: Emily L
authors: EL
authors: Paterson
authors: Simon C
authors: SC
authors: Barry
authors: Anna
authors: A
authors: Tsykin
authors: Gelareh
authors: G
authors: Farshid
authors: Mathew A
authors: MA
authors: Vadas
authors: Yeesim
authors: Y
authors: Khew-Goodall
authors: Gregory J
authors: GJ
authors: Goodall
mesh_terms: D000199:Actins / Q000378:metabolism; D000818:Animals; D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology; D015820:Cadherins / Q000235:genetics / Q000378:metabolism; D002460:Cell Line; D004285:Dogs; D004848:Epithelium / Q000502:physiology*; D005260:Female; D017930:Genes, Reporter; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism; D008648:Mesoderm / Q000502:physiology*; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D046228:Microarray Analysis; D009361:Neoplasm Invasiveness; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D010641:Phenotype; D010750:Phosphoproteins / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D053773:Transforming Growth Factor beta1 / Q000378:metabolism; D000071799:Zinc Finger E-box-Binding Homeobox 1; D062826:Zonula Occludens-1 Protein
chemical_list: D000199:Actins; D015820:Cadherins; C108381:GEMIN2 protein, human; D018398:Homeodomain Proteins; D008565:Membrane Proteins; D035683:MicroRNAs; D009419:Nerve Tissue Proteins; D010750:Phosphoproteins; D034741:RNA, Small Interfering; D016601:RNA-Binding Proteins; C569042:TJP1 protein, human; D014157:Transcription Factors; D053773:Transforming Growth Factor beta1; C486307:ZEB1 protein, human; D000071799:Zinc Finger E-box-Binding Homeobox 1; D062826:Zonula Occludens-1 Protein