Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
24
pubmed:dateCreated
2007-12-19
pubmed:abstractText
Currently, the most efficacious treatment for malignant gliomas is temozolomide; however, gliomas expressing the DNA repair enzyme O(6)-methylguanine-DNA methyltransferase (MGMT) are resistant to this drug. Strong clinical evidence shows that gliomas with methylation and subsequent silencing of the MGMT promoter are sensitive to temozolomide. Based on the fact that adenoviral proteins directly target and inactivate key DNA repair genes, we hypothesized that the oncolytic adenovirus Delta-24-RGD could be successfully combined with temozolomide to overcome the reported MGMT-mediated resistance. Our studies showed that the combination of Delta-24-RGD and temozolomide induces a profound therapeutic synergy in glioma cells. We observed that Delta-24-RGD treatment overrides the temozolomide-mediated G(2)-M arrest. Furthermore, Delta-24-RGD infection was followed by down-modulation of the RNA levels of MGMT. Chromatin immunoprecipitation assays showed that Delta-24-RGD prevented the recruitment of p300 to the MGMT promoter. Importantly, using mutant adenoviruses and wild-type and dominant-negative forms of the p300 protein, we showed that Delta-24-RGD interaction with p300 was required to induce silencing of the MGMT gene. Of further clinical relevance, the combination of Delta-24-RGD and temozolomide significantly improved the survival of glioma-bearing mice. Collectively, our data provide a strong mechanistic rationale for the combination of oncolytic adenoviruses and temozolomide, and should propel the clinical testing of this therapy approach in patients with malignant gliomas.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
1538-7445
pubmed:author
pubmed:issnType
Electronic
pubmed:day
15
pubmed:volume
67
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
11499-504
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Adenovirus-based strategies overcome temozolomide resistance by silencing the O6-methylguanine-DNA methyltransferase promoter.
pubmed:affiliation
Department of Neuro-Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030, USA. mmalonso@mdanderson.org
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural