miR-124 radiosensitizes human glioma cells by targeting CDK4

J Neurooncol. 2013 Sep;114(3):263-74. doi: 10.1007/s11060-013-1179-2. Epub 2013 Jun 13.

Abstract

The aberrant expression of cyclin-dependent kinase-4 (CDK4) has previously been observed in human brain glioma. Furthermore, it is observed that up-regulation of CDK4 is associated with therapy resistance and relapse. However, the mechanisms behind these phenomena remain unclear. Here, we demonstrated that elevated CDK4 expression is correlated with poor prognosis in glioma after radiotherapy and that CDK4 knockdown conferred radiosensitivity in glioma cell lines. CDK4 was identified as potential downstream target of miR-124 through bioinformatics analysis and dual-firefly luciferase reporter assay. Furthermore, restoration of miR-124 could confer radiosensitivity. Cell differentiation agent-2 (CDA-2) mimicked the effect of miR-124 restoration and CDK4 knockdown, and sensitized xenografts to radiation in an animal model. Our findings demonstrated for the first time that CDK4 was a downstream target of miR-124 and that CDA-2 could radiosensitize Glioblastoma multiforme cells through the MiR-124-CDK4 axis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Animals
  • Apoptosis
  • Blotting, Western
  • Brain Neoplasms / genetics
  • Brain Neoplasms / pathology*
  • Brain Neoplasms / radiotherapy
  • Cell Differentiation
  • Cell Proliferation
  • Cyclin-Dependent Kinase 4 / antagonists & inhibitors
  • Cyclin-Dependent Kinase 4 / genetics
  • Cyclin-Dependent Kinase 4 / metabolism*
  • Cytidine Deaminase / genetics
  • Cytidine Deaminase / metabolism
  • Female
  • Fluorescent Antibody Technique
  • Glioblastoma / genetics
  • Glioblastoma / pathology*
  • Glioblastoma / radiotherapy
  • Humans
  • Immunoenzyme Techniques
  • In Situ Hybridization
  • Luciferases / metabolism
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Mice, Nude
  • MicroRNAs / genetics*
  • Middle Aged
  • RNA, Messenger / genetics
  • RNA, Small Interfering / genetics
  • Radiation Tolerance / genetics*
  • Radiation, Ionizing
  • Real-Time Polymerase Chain Reaction
  • Reverse Transcriptase Polymerase Chain Reaction
  • Tumor Cells, Cultured

Substances

  • MIRN124 microRNA, human
  • MicroRNAs
  • RNA, Messenger
  • RNA, Small Interfering
  • Luciferases
  • CDK4 protein, human
  • Cyclin-Dependent Kinase 4
  • AICDA (activation-induced cytidine deaminase)
  • Cytidine Deaminase