MicroRNA-145 inhibits the growth, invasion, metastasis and angiogenesis of neuroblastoma cells through targeting hypoxia-inducible factor 2 alpha

Oncogene. 2014 Jan 16;33(3):387-97. doi: 10.1038/onc.2012.574. Epub 2012 Dec 10.

Abstract

Recent evidence shows that hypoxia-inducible factor 2 alpha (HIF-2α) may have critical roles in the growth and progression of neuroblastoma (NB) under non-hypoxic conditions. However, the underlying mechanisms and clinical potentials of normoxic HIF-2α expression in NB still remain largely unknown. In this study, HIF-2α immunostaining was identified in 26/42 NB tissues, which was correlated with clinicopathological features. In subtotal 20 NB cases, microRNA-145 (miR-145) was downregulated and inversely correlated with HIF-2α expression. Bioinformatics analysis revealed a putative miR-145 binding site in the 3'-untranslated region (3'-UTR) of HIF-2α messenger RNA (mRNA). Overexpression or knockdown of miR-145 responsively altered both the mRNA and protein levels of HIF-2α and its downstream genes, cyclin D1, matrix metalloproteinase 14 and vascular endothelial growth factor, in normoxically cultured NB cell lines SH-SY5Y and SK-N-SH. In a luciferase reporter system, miR-145 downregulated the luciferase activity of HIF-2α 3'-UTR, and these effects were abolished by a mutation in the putative miR-145-binding site. Overexpression of miR-145 suppressed the growth, invasion, metastasis and angiogenesis of SH-SY5Y and SK-N-SH cells in vitro and in vivo, while restoration of HIF-2α expression rescued the tumor cells from miR-145-mediated defects in these biological features. Furthermore, anti-miR-145 inhibitor rescued the HIF-2α knockdown-mediated repression on the growth, migration, invasion and angiogenesis of NB cells. These data indicate that miR-145 suppresses HIF-2α expression via the binding site in the 3'-UTR under normoxic conditions, thus inhibiting the aggressiveness and angiogenesis of NB.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Basic Helix-Loop-Helix Transcription Factors / genetics*
  • Basic Helix-Loop-Helix Transcription Factors / metabolism
  • Blotting, Western
  • Cell Line
  • Cell Proliferation*
  • Cells, Cultured
  • Child, Preschool
  • Cyclin D1 / genetics
  • Cyclin D1 / metabolism
  • Female
  • Gene Expression Regulation, Neoplastic
  • Gene Knockdown Techniques
  • Humans
  • Infant
  • Male
  • Matrix Metalloproteinase 14 / genetics
  • Matrix Metalloproteinase 14 / metabolism
  • Mice
  • Mice, Nude
  • MicroRNAs / genetics*
  • Neoplasm Invasiveness
  • Neoplasm Metastasis
  • Neovascularization, Pathologic / genetics*
  • Neovascularization, Pathologic / pathology
  • Neuroblastoma / genetics*
  • Neuroblastoma / pathology
  • Neuroblastoma / therapy
  • Reverse Transcriptase Polymerase Chain Reaction
  • Vascular Endothelial Growth Factor A / genetics
  • Vascular Endothelial Growth Factor A / metabolism
  • Xenograft Model Antitumor Assays / methods

Substances

  • Basic Helix-Loop-Helix Transcription Factors
  • MIRN145 microRNA, human
  • MicroRNAs
  • Vascular Endothelial Growth Factor A
  • Cyclin D1
  • endothelial PAS domain-containing protein 1
  • Matrix Metalloproteinase 14