MicroRNA miR-210 modulates cellular response to hypoxia through the MYC antagonist MNT

Cell Cycle. 2009 Sep 1;8(17):2756-68. doi: 10.4161/cc.8.17.9387. Epub 2009 Sep 29.

Abstract

The hypoxia-inducible factor (HIF) pathway is essential for cell survival under low oxygen and plays an important role in tumor cell homeostasis. We investigated the function of miR-210, the most prominent microRNA upregulated by hypoxia and a direct transcriptional target of HIFs. miR-210 expression was elevated in multiple cancer types and correlated with metastasis of breast and melanoma tumors. miR-210 overexpression in cancer cell lines bypassed hypoxia-induced cell cycle arrest and partially reversed the hypoxic gene expression signature. We identified MNT, a known MYC antagonist, as a miR-210 target. MNT mRNA contains multiple miR-210 binding sites in the 3' UTR and its knockdown phenocopied miR-210 overexpression. Furthermore, loss of MYC abolished miR-210-mediated override of hypoxia-induced cell cycle arrest. Comparison of miR-210 and MYC overexpression with MNT knockdown signatures also indicated that miR-210 triggered a "MYC-like" transcriptional response. Thus, miR-210 influences the hypoxia response in tumor cells through targeting a key transcriptional repressor of the MYC-MAX network.

MeSH terms

  • Basic Helix-Loop-Helix Leucine Zipper Transcription Factors / genetics
  • Basic Helix-Loop-Helix Leucine Zipper Transcription Factors / metabolism*
  • Basic Helix-Loop-Helix Transcription Factors / metabolism
  • Binding Sites
  • Cell Cycle
  • Cell Hypoxia
  • Cell Line, Tumor
  • Cluster Analysis
  • Gene Knockdown Techniques
  • Humans
  • Hypoxia-Inducible Factor 1 / metabolism
  • MicroRNAs / metabolism*
  • Models, Biological
  • Proto-Oncogene Proteins c-myc / antagonists & inhibitors*
  • Proto-Oncogene Proteins c-myc / genetics
  • Proto-Oncogene Proteins c-myc / metabolism
  • RNA, Small Interfering / metabolism
  • Repressor Proteins / genetics
  • Repressor Proteins / metabolism*
  • Up-Regulation

Substances

  • Basic Helix-Loop-Helix Leucine Zipper Transcription Factors
  • Basic Helix-Loop-Helix Transcription Factors
  • Hypoxia-Inducible Factor 1
  • MIRN210 microRNA, human
  • MNT protein, human
  • MicroRNAs
  • Proto-Oncogene Proteins c-myc
  • RNA, Small Interfering
  • Repressor Proteins
  • endothelial PAS domain-containing protein 1