GABAA-receptor expression in glioma cells is triggered by contact with neuronal cells


  • M. Synowitz
  • P. Ahmann
  • M. Matyash
  • S.A. Kuhn
  • B. Hofmann
  • C. Zimmer
  • F. Kirchhoff
  • J.C.W. Kiwit
  • H. Kettenmann


  • European Journal of Neuroscience


  • Eur J Neurosci 14 (8): 1294-1302


  • The expression of functional GABAA-receptors in glioma cells correlates with low malignancy of tumours and cell lines from glioma lack these receptors. Here we show that contact with neurons induces the expression of functional GABAA-receptors. C6 and F98 glioma cell lines were labelled by recombinant expression of enhanced green fluorescent protein injected into rat brain and studied in acute slices after two to three weeks of tumour growth. The cells responded to GABA or the specific agonist, muscimol with a current typical for GABAA-receptors, as studied with the patch-clamp technique. To get insight into the mechanism of GABAA receptor induction, the C6 or F98 cells were co-cultured with neurons, astrocytes, oligodendrocytes and microglia. Glioma cells expressed functional GABAA receptors within 24 h only in cultures where physical contact to neurons occurred. Activation of GABAA-receptors in the co-cultures attenuated glioma cell metabolism while blockade of the receptors increased metabolism. We conclude that with this form of interaction, neurons can influence tumour behaviour in the brain.