Targeting the glyoxalase pathway enhances TRAIL efficacy in cancer cells by downregulating the expression of antiapoptotic molecules

Mol Cancer Ther. 2012 Oct;11(10):2294-300. doi: 10.1158/1535-7163.MCT-12-0031. Epub 2012 Jul 11.


Methylglyoxal is an essential component in glycolysis and is known to be an inducer of apoptosis. Glyoxalase I (GLO1) metabolizes and inactivates methylglyoxal. GLO1 is known to be overexpressed in cancer cells and causes resistance to anticancer agents. We show for the first time that methylglyoxal treatment or the silencing of GLO1 enhances sensitivity to the promising anticancer agent TRAIL in malignant tumor cells. Methylglyoxal suppressed the expression of antiapoptotic factors, X-linked inhibitor of apoptosis protein (XIAP), survivin, cIAP1, Bcl-2, and Bcl-xL, without affecting TRAIL receptors, DR4 and DR5. Knockdown of XIAP or survivin by siRNA also enhanced TRAIL-induced apoptosis, indicating that downregulation of XIAP and survivin expression by methylglyoxal contributes to the enhancement of TRAIL activity. Furthermore, methylglyoxal decreased NF-κB activity with or without TRAIL treatment. On the other hand, the knockdown of GLO1 by siRNA enhanced TRAIL-induced apoptosis via the downregulation of XIAP and survivin expression. In conclusion, our results strongly suggest that sensitivity to TRAIL is increased by inhibition of the glyoxalase pathway and that the combination of TRAIL with methylglyoxal or glyoxalase inhibitors may be useful for a novel combination chemotherapy.

MeSH terms

  • Apoptosis / drug effects
  • Apoptosis / genetics
  • Apoptosis Regulatory Proteins / genetics*
  • Apoptosis Regulatory Proteins / metabolism
  • Caspases / metabolism
  • Cell Line, Tumor
  • Down-Regulation / drug effects*
  • Down-Regulation / genetics
  • Drug Screening Assays, Antitumor
  • G1 Phase / drug effects
  • G1 Phase / genetics
  • Gene Expression Regulation, Neoplastic / drug effects
  • Gene Knockdown Techniques
  • Humans
  • Inhibitor of Apoptosis Proteins / genetics
  • Inhibitor of Apoptosis Proteins / metabolism
  • Lactoylglutathione Lyase / antagonists & inhibitors*
  • Lactoylglutathione Lyase / metabolism
  • Molecular Targeted Therapy*
  • NF-kappa B / metabolism
  • Neoplasms / drug therapy*
  • Neoplasms / enzymology
  • Neoplasms / genetics
  • Neoplasms / pathology*
  • Pyruvaldehyde / pharmacology
  • Survivin
  • TNF-Related Apoptosis-Inducing Ligand / pharmacology*
  • X-Linked Inhibitor of Apoptosis Protein / genetics
  • X-Linked Inhibitor of Apoptosis Protein / metabolism


  • Apoptosis Regulatory Proteins
  • BIRC5 protein, human
  • Inhibitor of Apoptosis Proteins
  • NF-kappa B
  • Survivin
  • TNF-Related Apoptosis-Inducing Ligand
  • X-Linked Inhibitor of Apoptosis Protein
  • XIAP protein, human
  • Pyruvaldehyde
  • Caspases
  • Lactoylglutathione Lyase