title: Butyric acid prodrugs are histone deacetylase inhibitors that show antineoplastic activity and radiosensitizing capacity in the treatment of malignant gliomas.
abstract: Histone modification has emerged as a promising approach to cancer therapy. We explored the efficacy of a novel class of histone deacetylase inhibitors in the treatment of malignant gliomas. Treatment of glioma cell lines with two butyric acid derivatives, pivaloylomethyl butyrate (AN-9) and butyroyloxymethyl butyrate (AN-1), induced hyperacetylation, increased p21(Cip1) expression, inhibited proliferation, and enhanced apoptosis. Histone deacetylase inhibitor-induced apoptosis was mediated primarily by caspase-8. Treatment of cells with AN-1 or AN-9 for 24 hours before exposure to gamma-irradiation potentiated further caspase-8 activity and resultant apoptosis. Clonogenic survival curves revealed marked reductions in cell renewal capacity of U251 MG cells exposed to combinations of AN-1 and radiation. Preliminary in vivo experiments using human glioma cell lines grown as xenografts in mouse flanks suggest in vivo efficacy of AN-9. The data suggest that novel butyric acid prodrugs provide a promising treatment strategy for malignant gliomas as single agents and in combination with radiation therapy.
authors.affiliation: Comprehensive Cancer Center, University of California at San Francisco, 2340 Sutter Street, San Francisco, CA 94115, USA. memeer@cc.ucsf.edu
authors.forename: Michal
authors.initials: M
authors.lastname: Entin-Meer
authors.forename: Ada
authors.initials: A
authors.lastname: Rephaeli
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Yang
authors.forename: Abraham
authors.initials: A
authors.lastname: Nudelman
authors.forename: Scott R
authors.initials: SR
authors.lastname: VandenBerg
authors.forename: Daphne Adele
authors.initials: DA
authors.lastname: Haas-Kogan
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D001253:Astrocytes / Q000187:drug effects; D015153:Blotting, Western; D020148:Butyric Acid / Q000494:pharmacology*; D020169:Caspases / Q000378:metabolism; D045744:Cell Line, Tumor; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005910:Glioma / Q000201:enzymology / Q000473:pathology*; D056572:Histone Deacetylase Inhibitors; D006655:Histone Deacetylases / Q000378:metabolism; D006801:Humans; D011355:Prodrugs / Q000494:pharmacology*; D011838:Radiation-Sensitizing Agents / Q000494:pharmacology*
chemical_list: D000970:Antineoplastic Agents; C493956:CDKN1A protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; D004791:Enzyme Inhibitors; D056572:Histone Deacetylase Inhibitors; D011355:Prodrugs; D011838:Radiation-Sensitizing Agents; D020148:Butyric Acid; D020169:Caspases; D006655:Histone Deacetylases