A possible regulatory role of glyoxalase I in cell viability of human prostate cancer

Urol Res. 2002 May;30(2):116-21. doi: 10.1007/s00240-002-0244-7.

Abstract

A role of glyoxalase I (Gly-I), a detoxifying enzyme, in cell viability of prostate cancer was investigated. Cell extracts obtained from 66 prostate tissue specimens and prostatic cancer PC-3 cells were assayed for Gly-I activity using the spectrophotometric method. Gly-I activity was consistently more than eightfold higher in prostate cancer (CAP) specimens (n = 37) than in non-cancerous (NCP) specimens (n = 29). To understand the importance of such a high Gly-I activity in CAP specimens, the effects of methylglyoxal (MG) on PC-3 cells were examined in vitro. MG, a putative toxic glycolytic metabolite, was capable of inducing severe (> 99%) cell death in 24 h, along with a significant reduction in activities of Gly-I as well as glyceraldehyde 3-phosphate dehydrogenase (G3PDH), a key glycolytic enzyme. However, such severe cell death was effectively (approximately 85%) prevented with N-acetylcysteine (NAC), a precursor of reduced glutathione (GSH) that is an essential cofactor for Gly-I, accompanied by the intact Gly-I and G3PDH activities. Therefore, Gly-I may play a critical detoxifying role in glycolysis to maintain cellular activity and viability of prostatic cancer cells.

MeSH terms

  • Acetylcysteine / pharmacology
  • Cell Survival / drug effects
  • Enzyme Inhibitors / pharmacology
  • Glyceraldehyde-3-Phosphate Dehydrogenases / antagonists & inhibitors
  • Glycolysis / drug effects
  • Humans
  • In Vitro Techniques
  • Lactoylglutathione Lyase / antagonists & inhibitors
  • Lactoylglutathione Lyase / metabolism*
  • Male
  • Prostatic Neoplasms / physiopathology*
  • Pyruvaldehyde / pharmacology
  • Tumor Cells, Cultured

Substances

  • Enzyme Inhibitors
  • Pyruvaldehyde
  • Glyceraldehyde-3-Phosphate Dehydrogenases
  • Lactoylglutathione Lyase
  • Acetylcysteine