Involvement of Hydrogen Peroxide in Safingol-Induced Endonuclease G-Mediated Apoptosis of Squamous Cell Carcinoma Cells

  title={Involvement of Hydrogen Peroxide in Safingol-Induced Endonuclease G-Mediated Apoptosis of Squamous Cell Carcinoma Cells},
  author={Masakazu Hamada and Ken Wakabayashi and Atsushi Masui and So-ichi Iwai and Tomoaki Imai and Yoshiaki Yura},
  journal={International Journal of Molecular Sciences},
  pages={2660 - 2671}
Safingol, a L-threo-dihydrosphingosine, induced the nuclear translocation of a mitochondrial apoptogenic mediator—endonuclease G (endo G)—and apoptosis of human oral squamous cell carcinoma (SCC) cells. Upstream mediators remain largely unknown. The levels of hydrogen peroxide (H2O2) in cultured oral SCC cells were measured. Treatment with safingol increased intracellular H2O2 levels but not extracellular H2O2 levels, indicating the production of H2O2. The cell killing effect of safingol and… Expand
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