title: MiR-214 negatively regulates proliferation and WNT/β-catenin signaling in breast cancer.
abstract: To analyze the function and mechanism of miR-214 in regulating breast cancer cell proliferation.
  
  
  
  MiR-214 expression level was measured by quantitative reverse transcription Polymerase Chain Reaction (qRT-PCR). The protein level of β-catenin, PCNA and WNT targets (cyclin D1 and c-Myc) was evaluated by Western blot analysis. The effects of miR-214 on cell proliferation and cisplatin sensitivity were assessed by Cell Counting Kit-8 (CCK-8) assay and/or 5-bromo-2'-deoxyuridine (BrdU) assay. The effect of miR-214 on β-catenin and WNT signaling activity was tested by luciferase reporter assay.
  
  
  
  MiR-214 was significantly downregulated in breast cancer tissues and was inversely correlated with β-catenin expression. Forced expression of miR-214 in breast cancer cell line MCF-7 led to a decrease in cell proliferation and an increase in cisplatin sensitivity. Moreover, forced expression of miR-214 decreased the activity of WNT luciferase reporter and the luciferase reporter containing the 3'-untranslated region (3'UTR) of β-catenin, whereas antisense inhibitor of miR-214 showed an opposite effect. Finally, miR-214 decreased the expression of β-catenin and multiple WNT target genes.
  
  
  
  MiR-214 is downregulated and serves as a novel tumor suppressor in breast cancer. Forced expression of miR-214 in breast cancer cells diminished cancer cell survival possibly through inhibiting WNT signaling by direct repression of β-catenin.
authors.affiliation: General Surgery Department of Shenzhen University Affiliated Hospital, Shenzhen, China. sjyi2009@163.com.
authors.forename: S-J
authors.initials: SJ
authors.lastname: Yi
authors.forename: L-L
authors.initials: LL
authors.lastname: Li
authors.forename: W-B
authors.initials: WB
authors.lastname: Tu
mesh_terms: D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology*; D049109:Cell Proliferation; D005260:Female; D006801:Humans; D035683:MicroRNAs / Q000235:genetics*; D060449:Wnt Signaling Pathway; D051176:beta Catenin / Q000378:metabolism*
chemical_list: C547397:MIRN214 microRNA, human; D035683:MicroRNAs; D051176:beta Catenin