MicroRNA-21 down-regulates the expression of tumor suppressor PDCD4 in human glioblastoma cell T98G

Cancer Lett. 2008 Dec 18;272(2):197-205. doi: 10.1016/j.canlet.2008.06.034. Epub 2008 Nov 13.


MicroRNAs have been linked to different cancer-related processes. The microRNA miR-21 appears to function as an anti-apoptosis factor in glioblastomas. However, the functional target genes of miR-21 are largely unknown in glioblastomas. In this study, bioinformatics analysis was used to identify miR-21 target sites in various genes. Luciferase activity assay showed that a number of genes involved in apoptosis, PDCD4, MTAP, and SOX5, carry putative miR-21 binding sites. Expression of PDCD4 protein correlates inversely with expression of miR-21 in a number of human glioblastoma cell lines such as T98G, A172, U87, and U251. Inhibition of miR-21 increases endogenous levels of PDCD4 in cell line T98G and over-expression miR-21 inhibits PDCD4-dependent apoptosis. Together, these results indicate that miR-21 expression plays a key role in regulating cellular processes in glioblastomas and may serve as a target for effective therapies.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoptosis Regulatory Proteins / genetics*
  • Base Sequence
  • Blotting, Northern
  • Blotting, Western
  • Brain Neoplasms / genetics*
  • Brain Neoplasms / pathology
  • Cell Line, Tumor
  • DNA Primers
  • Down-Regulation / physiology*
  • Gene Expression Regulation, Neoplastic / physiology*
  • Glioblastoma / genetics*
  • Glioblastoma / pathology
  • Humans
  • In Situ Nick-End Labeling
  • MicroRNAs / physiology*
  • RNA-Binding Proteins / genetics*
  • Reverse Transcriptase Polymerase Chain Reaction


  • Apoptosis Regulatory Proteins
  • DNA Primers
  • MicroRNAs
  • PDCD4 protein, human
  • RNA-Binding Proteins