TRP-2 specifically decreases WM35 cell sensitivity to oxidative stress

Free Radic Biol Med. 2008 Mar 15;44(6):1023-31. doi: 10.1016/j.freeradbiomed.2007.11.021. Epub 2007 Dec 14.

Abstract

TRP-2 (dopachrome tautomerase) is a melanogenic enzyme whose expression was recently reported to modulate melanocyte response to different cytotoxic events. Here we studied a possible role of TRP-2 in the oxidative stress response in the amelanotic WM35 melanoma cell line. Cell viability assays showed that TRP-2 overexpression in WM35 cells reduced their sensitivity to oxidative stress. Comet assays linked TRP-2 expression to DNA damage protection, and high-performance liquid chromotography-tandem mass spectrometry experiments showed an increase in intracellular glutathione in TRP-2-overexpressing cells. These effects were specifically reversed when TRP-2 was silenced by RNA interference. Nevertheless, these properties appeared to depend on a particular cell environment because expression of TRP-2 failed to rescue HEK epithelial cells exposed to similar treatments.

MeSH terms

  • Blotting, Western
  • Cell Line, Tumor
  • Chromatography, High Pressure Liquid
  • Comet Assay
  • DNA Damage / physiology
  • Epithelial Cells / metabolism*
  • Glutathione
  • Humans
  • Immunohistochemistry
  • Intramolecular Oxidoreductases / metabolism*
  • Melanoma / metabolism*
  • Oxidative Stress / physiology*
  • RNA Interference
  • Tandem Mass Spectrometry

Substances

  • Intramolecular Oxidoreductases
  • dopachrome isomerase
  • Glutathione