A sphingosine kinase inhibitor induces cell death in temozolomide resistant glioblastoma cells

Cancer Chemother Pharmacol. 2009 Oct;64(5):1053-8. doi: 10.1007/s00280-009-1063-0. Epub 2009 Jul 12.


Purpose: Sphingosine kinase is an oncogene that is up-regulated in several solid tumors. The product of the sphingosine kinase activity, sphingosine-1-phosphate is a potent mitogen involved in diverse cell processes such as cell survival and migration. Current standard therapy in the treatment of glioblastoma multiforme (GBM) is a combination of surgery, radiation, and chemotherapy using the drug temozolomide (TMZ). However, virtually all tumors become resistant to TMZ. Therefore, new drug targets are necessary. In this study, we investigated whether inhibiting sphingosine kinase could induce cell death in TMZ-resistant GBM cells.

Methods: To study TMZ resistance in vitro, we have generated TMZ-resistant cell lines from established GBM cells. We used a potent inhibitor of sphingosine kinase to study its effect on colony formation and cell growth in GBM cells with a limited dilution and WST assay. Moreover, cell death was determined by measuring caspase-3 activity using flow cytometry.

Results: A sphingosine kinase inhibitor reduced cell colony formation and activated caspase-3 in both TMZ-sensitive and resistant GBM cells.

Conclusion: Addition of a sphingosine kinase inhibitor to the standard chemotherapy regimen against GBM may be beneficial.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Aniline Compounds / pharmacology*
  • Antineoplastic Agents, Alkylating / pharmacology*
  • Apoptosis / drug effects
  • Caspase 3 / metabolism
  • Cell Death / drug effects
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Dacarbazine / analogs & derivatives*
  • Dacarbazine / pharmacology
  • Drug Resistance, Neoplasm
  • Enzyme Inhibitors / pharmacology*
  • Flow Cytometry
  • Glioblastoma / drug therapy*
  • Glioblastoma / pathology
  • Humans
  • Indicator Dilution Techniques
  • Oligonucleotide Array Sequence Analysis
  • Phosphotransferases (Alcohol Group Acceptor) / antagonists & inhibitors*
  • Reverse Transcriptase Polymerase Chain Reaction
  • Temozolomide
  • Thiazoles / pharmacology*


  • 2-(4-hydroxyanilino)-4-(4-chlorophenyl)thiazole
  • Aniline Compounds
  • Antineoplastic Agents, Alkylating
  • Enzyme Inhibitors
  • Thiazoles
  • Dacarbazine
  • Phosphotransferases (Alcohol Group Acceptor)
  • sphingosine kinase
  • Caspase 3
  • Temozolomide