Inhibition of Casein kinase-2 induces p53-dependent cell cycle arrest and sensitizes glioblastoma cells to tumor necrosis factor (TNFα)-induced apoptosis through SIRT1 inhibition

Cell Death Dis. 2012 Feb 9;3(2):e271. doi: 10.1038/cddis.2012.10.

Abstract

Glioblastoma multiforme (GBM) are resistant to TNFα-induced apoptosis and blockade of TNFα-induced NF-κB activation sensitizes glioma cells to apoptosis. As Casein kinase-2 (CK2) induces aberrant NF-κB activation and as we observed elevated CK2 levels in GBM tumors, we investigated the potential of CK2 inhibitors (CK2-Is) - DRB and Apigenin in sensitizing glioma cells to TNFα-induced apoptosis. CK2-Is and CK2 small interfering RNA (siRNA) reduced glioma cell viability, inhibited TNFα-mediated NF-κB activation, and sensitized cell to TNFα-induced apoptosis. Importantly, CK2-Is activated p53 function in wild-type but not in p53 mutant cells. Activation of p53 function involved its increased transcriptional activation, DNA-binding ability, increased expression of p53 target genes associated with cell cycle progression and apoptosis. Moreover, CK2-Is decreased telomerase activity and increased senescence in a p53-dependent manner. Apoptotic gene profiling indicated that CK2-Is differentially affect p53 and TNFα targets in p53 wild-type and mutant glioma cells. CK2-I decreased MDM2-p53 association and p53 ubiquitination to enhance p53 levels. Interestingly, CK2-Is downregulated SIRT1 activity and over-expression of SIRT1 decreased p53 transcriptional activity and rescued cells from CK2-I-induced apoptosis. This ability of CK2-Is to sensitize glioma to TNFα-induced death via multiple mechanisms involving abrogation of NF-κB activation, reactivation of wild-type p53 function and SIRT1 inhibition warrants investigation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apigenin / pharmacology
  • Apigenin / therapeutic use
  • Apoptosis
  • Brain / drug effects
  • Brain / metabolism
  • Brain / pathology
  • Brain Neoplasms / genetics
  • Brain Neoplasms / metabolism
  • Brain Neoplasms / pathology*
  • Casein Kinase II / antagonists & inhibitors*
  • Casein Kinase II / genetics
  • Cell Cycle Checkpoints / drug effects
  • Cell Line, Tumor
  • Dichlororibofuranosylbenzimidazole / pharmacology
  • Dichlororibofuranosylbenzimidazole / therapeutic use
  • Gene Expression Regulation, Neoplastic
  • Glioblastoma / genetics
  • Glioblastoma / metabolism
  • Glioblastoma / pathology*
  • Humans
  • NF-kappa B / genetics
  • NF-kappa B / metabolism
  • Protein Binding / genetics
  • Protein Kinase Inhibitors / pharmacology*
  • Proto-Oncogene Proteins c-mdm2 / genetics
  • Proto-Oncogene Proteins c-mdm2 / metabolism
  • RNA, Small Interfering / genetics
  • Signal Transduction
  • Sirtuin 1 / antagonists & inhibitors*
  • Sirtuin 1 / genetics
  • Telomerase / genetics
  • Telomerase / metabolism
  • Transfection
  • Tumor Necrosis Factor-alpha / pharmacology
  • Tumor Suppressor Protein p53 / genetics
  • Tumor Suppressor Protein p53 / metabolism

Substances

  • NF-kappa B
  • Protein Kinase Inhibitors
  • RNA, Small Interfering
  • Tumor Necrosis Factor-alpha
  • Tumor Suppressor Protein p53
  • Dichlororibofuranosylbenzimidazole
  • Apigenin
  • MDM2 protein, human
  • Proto-Oncogene Proteins c-mdm2
  • Casein Kinase II
  • Telomerase
  • SIRT1 protein, human
  • Sirtuin 1