Document Detail


Bortezomib-induced sensitization of malignant human glioma cells to vorinostat-induced apoptosis depends on reactive oxygen species production, mitochondrial dysfunction, Noxa upregulation, Mcl-1 cleavage, and DNA damage.
MedLine Citation:
PMID:  22086447     Owner:  NLM     Status:  Publisher    
Abstract/OtherAbstract:
Glioblastomas are invasive tumors with poor prognosis despite current therapies. Histone deacetylase inhibitors (HDACIs) represent a class of agents that can modulate gene expression to reduce tumor growth, and we and others have noted some antiglioma activity from HDACIs, such as vorinostat, although insufficient to warrant use as monotherapy. We have recently demonstrated that proteasome inhibitors, such as bortezomib, dramatically sensitized highly resistant glioma cells to apoptosis induction, suggesting that proteasomal inhibition may be a promising combination strategy for glioma therapeutics. In this study, we examined whether bortezomib could enhance response to HDAC inhibition in glioma cells. Although primary cells from glioblastoma multiforme (GBM) patients and established glioma cell lines did not show significant induction of apoptosis with vorinostat treatment alone, the combination of vorinostat plus bortezomib significantly enhanced apoptosis. The enhanced efficacy was due to proapoptotic mitochondrial injury and increased generation of reactive oxygen species. Our results also revealed that combination of bortezomib with vorinostat enhanced apoptosis by increasing Mcl-1 cleavage, Noxa upregulation, Bak and Bax activation, and cytochrome c release. Further downregulation of Mcl-1 using shRNA enhanced cell killing by the bortezomib/vorinostat combination. Vorinostat induced a rapid and sustained phosphorylation of histone H2AX in primary GBM and T98G cells, and this effect was significantly enhanced by co-administration of bortezomib. Vorinostat/bortezomib combination also induced Rad51 downregulation, which plays an important role in the synergistic enhancement of DNA damage and apoptosis. The significantly enhanced antitumor activity that results from the combination of bortezomib and HDACIs offers promise as a novel treatment for glioma patients. © 2011 Wiley Periodicals, Inc.
Authors:
Daniel R Premkumar; Esther P Jane; Naomi R Agostino; Joseph D Didomenico; Ian F Pollack
Related Documents :
9054667 - Expression and function of cd95 (fas/apo-1) in leukaemia-lymphoma tumour lines.
16227577 - Viral flip enhances wnt signaling downstream of stabilized beta-catenin, leading to con...
12167637 - Hepatocyte fas-associating death domain protein/mediator of receptor-induced toxicity (...
14563117 - The cd95 type i/type ii model.
18520337 - 17beta-estradiol and soy phytochemicals selectively induce a type 2 polarization in mes...
17922947 - Moderate alcohol consumption and the immune system: a review.
Publication Detail:
Type:  JOURNAL ARTICLE     Date:  2011-11-15
Journal Detail:
Title:  Molecular carcinogenesis     Volume:  -     ISSN:  1098-2744     ISO Abbreviation:  -     Publication Date:  2011 Nov 
Date Detail:
Created Date:  2011-11-16     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  8811105     Medline TA:  Mol Carcinog     Country:  -    
Other Details:
Languages:  ENG     Pagination:  -     Citation Subset:  -    
Copyright Information:
Copyright © 2011 Wiley Periodicals, Inc.
Affiliation:
Department of Neurosurgery, Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania; University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Transient but Not Stable ZEB1 Knockdown Dramatically Inhibits Growth of Malignant Pleural Mesothelio...
Next Document:  Validation of the respiratory toxics exposure score (RTES) for chronic obstructive pulmonary disease...