1. EZH2 Inhibition Sensitizes IDH1R132H-Mutant Gliomas to Histone Deacetylase Inhibitor
- Author
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Sprinzen, Lisa, Garcia, Franklin, Mela, Angeliki, Lei, Liang, Upadhyayula, Pavan, Mahajan, Aayushi, Humala, Nelson, Manier, Lisa, Caprioli, Richard, Quiñones-Hinojosa, Alfredo, Casaccia, Patrizia, and Canoll, Peter
- Subjects
Biomedical and Clinical Sciences ,Oncology and Carcinogenesis ,Genetics ,Stem Cell Research ,Brain Disorders ,Rare Diseases ,Neurosciences ,Cancer ,Clinical Research ,Brain Cancer ,Animals ,Mice ,Histone Deacetylase Inhibitors ,Histones ,Glioma ,Benzamides ,Biphenyl Compounds ,Morpholines ,Pyridones ,EZH2 ,H3K27 ,HDAC ,IDH1 ,OPC ,gliomagenesis ,Biological sciences ,Biomedical and clinical sciences - Abstract
Isocitrate Dehydrogenase-1 (IDH1) is commonly mutated in lower-grade diffuse gliomas. The IDH1R132H mutation is an important diagnostic tool for tumor diagnosis and prognosis; however, its role in glioma development, and its impact on response to therapy, is not fully understood. We developed a murine model of proneural IDH1R132H-mutated glioma that shows elevated production of 2-hydroxyglutarate (2-HG) and increased trimethylation of lysine residue K27 on histone H3 (H3K27me3) compared to IDH1 wild-type tumors. We found that using Tazemetostat to inhibit the methyltransferase for H3K27, Enhancer of Zeste 2 (EZH2), reduced H3K27me3 levels and increased acetylation on H3K27. We also found that, although the histone deacetylase inhibitor (HDACi) Panobinostat was less cytotoxic in IDH1R132H-mutated cells (either isolated from murine glioma or oligodendrocyte progenitor cells infected in vitro with a retrovirus expressing IDH1R132H) compared to IDH1-wild-type cells, combination treatment with Tazemetostat is synergistic in both mutant and wild-type models. These findings indicate a novel therapeutic strategy for IDH1-mutated gliomas that targets the specific epigenetic alteration in these tumors.
- Published
- 2024