Specific IKKbeta inhibitor IV blocks Streptonigrin-induced NF-kappaB activity and potentiates its cytotoxic effect on cancer cells

Mol Carcinog. 2009 Aug;48(8):678-84. doi: 10.1002/mc.20550.

Abstract

Many anticancer agents activate NF-kappaB, which plays an important role in the survival of cancer cells. Inhibition of NF-kappaB activity may therefore potentiate the efficacy of anticancer agents. We found that a previously used anticancer agent Streptonigrin (SN) was also a potent NF-kappaB inducer. Using a specific IKKbeta inhibitor IV (Podolin et al., J Pharmacol Exp Ther 2005; 312: 373-381), we revealed that the activation of NF-kappaB was mediated through DNA damage-induced activation of IKK complex. Furthermore, we demonstrated that SN-induced DNA damage was unrelated to reactive oxygen species but to the hydroquinone form of SN converted by the NAD(P)H:quinine oxidoreductase (NQO1). The study suggests that the combination of SN with IKK inhibitor may improve efficacy over the use of single agent.

MeSH terms

  • Antibiotics, Antineoplastic / pharmacology*
  • Blotting, Western
  • Caspases / metabolism
  • Cell Proliferation / drug effects
  • DNA Damage
  • Enzyme Inhibitors / pharmacology*
  • Histones / genetics
  • Histones / metabolism
  • Humans
  • I-kappa B Kinase / antagonists & inhibitors*
  • Melanoma / drug therapy*
  • Melanoma / metabolism
  • Melanoma / pathology
  • NAD(P)H Dehydrogenase (Quinone) / genetics
  • NAD(P)H Dehydrogenase (Quinone) / metabolism
  • NF-kappa B / antagonists & inhibitors
  • NF-kappa B / genetics
  • NF-kappa B / metabolism*
  • Pancreatic Neoplasms / drug therapy*
  • Pancreatic Neoplasms / metabolism
  • Pancreatic Neoplasms / pathology
  • Phosphorylation / drug effects
  • Reactive Oxygen Species / metabolism
  • Streptonigrin / pharmacology*
  • Tumor Cells, Cultured

Substances

  • Antibiotics, Antineoplastic
  • Enzyme Inhibitors
  • H2AX protein, human
  • Histones
  • NF-kappa B
  • Reactive Oxygen Species
  • Streptonigrin
  • NAD(P)H Dehydrogenase (Quinone)
  • NQO1 protein, human
  • I-kappa B Kinase
  • IKBKB protein, human
  • Caspases