Driving Neuronal Differentiation through Reversal of an ERK1/2-miR-124-SOX9 Axis Abrogates Glioblastoma Aggressiveness

Cell Rep. 2019 Aug 20;28(8):2064-2079.e11. doi: 10.1016/j.celrep.2019.07.071.

Abstract

Identifying cellular programs that drive cancers to be stem-like and treatment resistant is critical to improving outcomes in patients. Here, we demonstrate that constitutive extracellular signal-regulated kinase 1/2 (ERK1/2) activation sustains a stem-like state in glioblastoma (GBM), the most common primary malignant brain tumor. Pharmacological inhibition of ERK1/2 activation restores neurogenesis during murine astrocytoma formation, inducing neuronal differentiation in tumorspheres. Constitutive ERK1/2 activation globally regulates miRNA expression in murine and human GBMs, while neuronal differentiation of GBM tumorspheres following the inhibition of ERK1/2 activation requires the functional expression of miR-124 and the depletion of its target gene SOX9. Overexpression of miR124 depletes SOX9 in vivo and promotes a stem-like-to-neuronal transition, with reduced tumorigenicity and increased radiation sensitivity. Providing a rationale for reports demonstrating miR-124-induced abrogation of GBM aggressiveness, we conclude that reversal of an ERK1/2-miR-124-SOX9 axis induces a neuronal phenotype and that enforcing neuronal differentiation represents a therapeutic strategy to improve outcomes in GBM.

Keywords: brain; cancer; differentiation; glioblastoma; glioma; microRNA; neural stem cell; neurogenesis; neuron; tumor.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Astrocytoma / genetics
  • Astrocytoma / pathology
  • Benzamides / pharmacology
  • Brain Neoplasms / genetics
  • Brain Neoplasms / pathology*
  • Cell Differentiation* / drug effects
  • Cell Line, Tumor
  • Cell Survival / drug effects
  • Diphenylamine / analogs & derivatives
  • Diphenylamine / pharmacology
  • Disease Progression
  • Female
  • Glioblastoma / genetics
  • Glioblastoma / pathology*
  • Humans
  • MAP Kinase Signaling System* / drug effects
  • Male
  • Mice, Nude
  • MicroRNAs / genetics
  • MicroRNAs / metabolism*
  • Neoplasm Invasiveness
  • Neoplastic Stem Cells / drug effects
  • Neoplastic Stem Cells / metabolism
  • Neoplastic Stem Cells / pathology
  • Neurogenesis / drug effects
  • Neurons / drug effects
  • Neurons / metabolism
  • Neurons / pathology*
  • Phenotype
  • Protein Kinase Inhibitors / pharmacology
  • Radiation Tolerance / drug effects
  • SOX9 Transcription Factor / metabolism*

Substances

  • Benzamides
  • MIRN124 microRNA, human
  • MicroRNAs
  • Protein Kinase Inhibitors
  • SOX9 Transcription Factor
  • mirdametinib
  • Diphenylamine