
Linus[a]
Mol Cancer Ther. 2005 Dec;4(12):1952-61
Butyric acid prodrugs are histone deacetylase inhibitors that show antineoplastic activity and radiosensitizing capacity in the treatment of malignant gliomas.
Entin-Meer M, Rephaeli A, Yang X, Nudelman A, VandenBerg SR, Haas-Kogan DA.
Comprehensive Cancer Center, University of California at San Francisco, 2340 Sutter Street, San Francisco, CA 94115, USA. memeer@cc.ucsf.edu
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.