Downregulation of Src enhances the cytotoxic effect of temozolomide through AKT in glioma

Oncol Rep. 2013 Apr;29(4):1395-8. doi: 10.3892/or.2013.2240. Epub 2013 Jan 17.

Abstract

Src is an attractive target since it is overexpressed in a number of malignancies, including glioma. However, the mechanism of Src signaling as well as its silencing effect on temozolomide in glioma is not well known. We hypothesized that downregulation of Src may enhance the cytotoxic effect of temozolomide on glioma. As expected, Src was overexpressed in glioblastoma multiforme (GBM) compared with normal brain tissues. Src silencing suppressed tumor proliferation and induced apoptosis in glioma. In addition, Src silencing combined with temozolomide treatment resulted in significant inhibition of tumor growth. These effects may be mediated by AKT which is a downstream effector of Src, since downregulation of AKT exhibited a similar effect as Src siRNA when combined with temozolomide. Finally, we demonstrated that overexpression of AKT suppressed the enhanced cytotoxic effect of temozolomide mediated by Src silencing. Thus, the present study demonstrated that Src plays a biologically significant role in tumor proliferation and apoptosis and enhances the cytotoxic effect of temozolomide through AKT supression in glioma.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis / drug effects
  • Brain Neoplasms / drug therapy
  • Brain Neoplasms / genetics
  • Brain Neoplasms / pathology
  • Cell Line, Tumor
  • Dacarbazine / administration & dosage
  • Dacarbazine / analogs & derivatives*
  • Down-Regulation
  • Gene Expression Regulation, Neoplastic / drug effects
  • Glioblastoma / drug therapy
  • Glioblastoma / genetics
  • Glioblastoma / pathology
  • Glioma / drug therapy*
  • Glioma / genetics
  • Glioma / pathology
  • Humans
  • Mice
  • Oncogene Protein v-akt / antagonists & inhibitors
  • Oncogene Protein v-akt / genetics*
  • Signal Transduction / drug effects
  • Temozolomide
  • Xenograft Model Antitumor Assays
  • src-Family Kinases / genetics*

Substances

  • Dacarbazine
  • src-Family Kinases
  • Oncogene Protein v-akt
  • Temozolomide