Gefitinib's Limited Effectiveness in Treating Glioma Highlighted in New Study

Strategic Insights -

Researchers in Caen, France, have found that the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor gefitinib (Iressa, ZD1839) has limited effectiveness in treating malignant glioma, a type of brain cancer. The study, published in Clinical Cancer Research, used a panel of six human malignant gliomas with different molecular alterations to investigate responses to gefitinib. The results showed that EGFR amplification was associated with profuse tumor cell invasion, but treatment with gefitinib inhibited invasion in a dose-dependent manner. However, PTEN loss was found to be a determinant of resistance to treatment, and none of the tumors showed shrinkage after gefitinib treatment.

Key Takeaways:

  • Gefitinib (Iressa, ZD1839) has limited effectiveness in treating malignant glioma, a type of brain cancer.
  • EGFR amplification is associated with profuse tumor cell invasion, but gefitinib treatment inhibited invasion in a dose-dependent manner.
  • PTEN loss was found to be a determinant of resistance to gefitinib treatment.
  • Gefitinib had similar antiangiogenic effect in all of the tumors.
  • None of the tumors showed shrinkage after gefitinib treatment.
  • The study highlights the need for further research into the molecular mechanisms underlying glioma aggressiveness and treatment resistance.

Statistics:

  • 6 human malignant gliomas were used in the study.
  • 3 tumors with EGFR amplification showed inhibition of invasion after treatment with gefitinib.
  • 2 tumors with EGFR amplification showed only an antiproliferative effect after treatment with gefitinib.
  • 1 tumor with PTEN loss was resistant to treatment with gefitinib.
  • No mutations of the EGFR kinase domain were found in any of the tumors.
  • Gefitinib had similar antiangiogenic effect in all of the tumors.

Sources:

  • Guillamo, J.S. et al. "Molecular Mechanisms Underlying Effects of Epidermal Growth Factor Receptor Inhibition on Invasion, Proliferation, and Angiogenesis in Experimental Glioma." Clinical Cancer Research, vol. 15, no. 11, 2009, pp. 3697-3704.
  • Angiogenesis Weekly editors. Angiogenesis Weekly, 2009, courtesy of NewsRx.com.