Unknown,Transcriptomics,Genomics,Proteomics

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High-throughput small molecule screen identifies inhibitors of aberrant chromatin accessibility

ABSTRACT: Mutations in chromatin modifying proteins are associated with a variety of cancers. These mutations may result in characteristic patterns of accessible chromatin indicative of altered nucleosome positioning and depletion at regulatory elements. We describe the adaptation of Formaldehyde-Assisted Isolation of Regulatory Elements (FAIRE), a chemical method to enrich for nucleosome-depleted genomic regions, as a high-throughput, automated assay. We applied this method in a screen of epigenetically targeted small molecules by evaluating regions of aberrant nucleosome depletion mediated by EWS-FLI1, the chimeric transcription factor critical for the bone and soft tissue tumor Ewing Sarcoma. We identified a novel compound, UNC0621, which exhibited a dose-dependent reduction in chromatin accessibility, decreased Ewing Sarcoma cell viability, and inhibited anchorage-independent growth. We demonstrate that chromatin accessibility can be exploited for drug discovery efforts offering the advantage that it does not depend on the a priori selection of a single molecular target. Identified compounds can then be used for biological target discovery and potential therapeutic validation. HT-FAIRE was performed on Human Umbilical Vein Endothelial Cells (HUVEC) in duplicate. No reference/control experiment is necessary.

ORGANISM(S): Homo sapiens

SUBMITTER: Ian Davis

PROVIDER: E-GEOD-61735 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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High-throughput small molecule screen identifies inhibitors of aberrant chromatin accessibility

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