5-azacytidine reduces methylation, promotes differentiation and induces tumor regression in a patient-derived IDH1 mutant glioma xenograft Journal Article


Authors: Borodovsky, A.; Salmasi, V.; Turcan, S.; Fabius, A. W. M.; Baia, G. S.; Eberhart, C. G.; Weingart, J. D.; Gallia, G. L.; Baylin, S. B.; Chan, T. A.; Riggins, G. J.
Article Title: 5-azacytidine reduces methylation, promotes differentiation and induces tumor regression in a patient-derived IDH1 mutant glioma xenograft
Abstract: Somatic mutations in Isocitrate Dehydrogenase 1 (IDH1) are frequent in low grade and progressive gliomas and are characterized by the production of 2-hydroxyglutarate (2-HG) from α-ketoglutarate by the mutant enzyme. 2-HG is an "oncometabolite" that competitively inhibits α-KG dependent dioxygenases resulting in various widespread cellular changes including abnormal hypermethylation of genomic DNA and suppression of cellular differentiation. Despite the growing understanding of IDH mutant gliomas, the development of effective therapies has proved challenging in part due to the scarcity of endogenous mutant in vivo models. Here we report the generation of an endogenous IDH1 anaplastic astrocytoma model which rapidly grows in vivo, produces 2-HG and exhibits DNA hypermethylation. Using this model, we have demonstrated the preclinical efficacy and mechanism of action of the FDA approved demethylating drug 5-azacytidine in vivo. Long term administration of 5-azacytidine resulted in reduction of DNA methylation of promoter loci, induction of glial differentiation, reduction of cell proliferation and a significant reduction in tumor growth. Tumor regression was observed at 14 weeks and subsequently showed no signs of re-growth at 7 weeks despite discontinuation of therapy. These results have implications for clinical trials of demethylating agents for patients with IDH mutated gliomas.
Keywords: methylation; xenograft; astrocytoma; idh; 5-azacytidine; progressive glioma
Journal Title: Oncotarget
Volume: 4
Issue: 10
ISSN: 1949-2553
Publisher: Impact Journals  
Date Published: 2013-10-01
Start Page: 1737
End Page: 1747
Language: English
PROVIDER: scopus
PMCID: PMC3858560
PUBMED: 24077805
DOI/URL:
Notes: --- - Cited By (since 1996):1 - "Export Date: 2 December 2013" - "Source: Scopus"
Citation Impact
MSK Authors
  1. Timothy Chan
    317 Chan
  2. Armida Wanda Mathilde Fabius
    13 Fabius
  3. Sevin Turcan
    25 Turcan