gamma-Aminobutyric acid inhibits cholangiocarcinoma growth by cyclic AMP-dependent regulation of the protein kinase A/extracellular signal-regulated kinase 1/2 pathway | Academic Article individual record
abstract

We studied the effect of the inhibitory neurotransmitter, gamma-aminobutyric acid (GABA), in the regulation of cholangiocarcinoma growth. We determined the in vitro effect of GABA on the proliferation of the cholangiocarcinoma cell lines (Mz-ChA-1, HuH-28, and TFK-1) and evaluated the intracellular pathways involved. The effect of GABA on migration of Mz-ChA-1 cells was also evaluated. In vivo, Mz-ChA-1 cells were s.c. injected in athymic mice, and the effects of GABA on tumor size, tumor cell proliferation, apoptosis, collagen quantity, and the expression of vascular endothelial growth factor-A (VEGF-A) and VEGF-C (cancer growth regulators) were measured after 82 days. GABA decreased in vitro cholangiocarcinoma growth in a time-dependent and dose-dependent manner, by both cyclic AMP/protein kinase A- and D-myo-inositol-1,4,5-thriphosphate/Ca(2+)-dependent pathways, leading to down-regulation of extracellular signal-regulated kinase 1/2 phosphorylation. Blocking of GABA(A), GABA(B), and GABA(C) receptors prevented GABA inhibition of cholangiocarcinoma proliferation. GABA inhibited Mz-ChA-1 cell migration and, in vivo, significantly decreased tumor volume, tumor cell proliferation, and VEGF-A/C expression whereas increasing apoptosis compared with controls. An increase in collagen was evident in GABA-treated tumors. GABA decreases biliary cancer proliferation and reduces the metastatic potential of cholangiocarcinoma. GABA may represent a therapeutic agent for patients affected by malignancies of the biliary tract.

author list (cited authors)
Fava, G., Marucci, L., Glaser, S., Francis, H., De Morrow, S., Benedetti, A., ... Alpini, G.
publication date
2005
published in
keywords
  • Cyclic AMP-Dependent Protein Kinases
  • Gamma-Aminobutyric Acid
  • Cell Movement
  • Signal Transduction
  • Mice
  • Cholangiocarcinoma
  • Vascular Endothelial Growth Factor A
  • Male
  • Receptors, GABA-A
  • Humans
  • Cyclic AMP
  • GABA Agents
  • Receptors, GABA-B
  • Bile Duct Neoplasms
  • Mice, Inbred BALB C
  • Tumor Cells, Cultured
  • Mitogen-Activated Protein Kinase 3
  • Collagen
  • Cell Proliferation
  • Mitogen-Activated Protein Kinase 1
  • Phosphorylation
  • Animals
  • Mice, Nude
  • Vascular Endothelial Growth Factor C
citation count

68