Discovery of epigenetic probes against the bromodomain family of proteins

<p>Chemical probes are necessary for elucidating the biochemical roles of proteins. Bromodomains are protein-interaction modules found in a family of proteins implicated in the epigenetic regulation of transcription; however, the individual roles remain unknown for many bromodomain proteins, w...

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Main Author: Clark, P
Other Authors: Dixon, D
Format: Thesis
Language:English
Published: 2015
Subjects:
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author Clark, P
author2 Dixon, D
author_facet Dixon, D
Clark, P
author_sort Clark, P
collection OXFORD
description <p>Chemical probes are necessary for elucidating the biochemical roles of proteins. Bromodomains are protein-interaction modules found in a family of proteins implicated in the epigenetic regulation of transcription; however, the individual roles remain unknown for many bromodomain proteins, without potent and selective ligands available to assist in their study. From lead compounds, a structure-based drug discovery program was to be explored with the use of biophysical assays and appropriate chemical methods to expediate development of probes against a number of these proteins. A fragment lead against BRD4 was developed into PNZ5, a potent (<em>K</em><sub>D</sub> 5 nM) BRD4 probe with a high ligand efficiency. Although enantioselective syntheses and the use of an alternative synthetic route were unsuccessful, PNZ5 showed cytotoxic activity against gastric cancer cell lines that had proved resilient to existing anticancer agents. Optimisation of a lead compound against BRD9 resulted in the development of LP99, the first reported BRD7/9 probe, that was potent (BRD9 <em>K</em><sub>D</sub> 99 nM, BRD7 <em>K</em><sub>D</sub> 909 nM), selective amongst bromodomain proteins and active in cells. An enantioselective synthesis was performed using chiral organocatalyts and LP99 was used to identify a previously unknown role of BRD7/9 in the regulation of inflammatory processes. Research is ongoing to assess further biochemical roles of these proteins with LP99. Arising from a more potent lead against BRD9, a series of structurally related compounds were synthesised to explore SAR around this ligand, however no improvement on the affinity of the lead was realised. Finally, based on disclosed lead structures against PCAF, a series of compounds were synthesised to replicate their activity. A number of important binding interactions were assessed and a lead structure was identified (<em>K</em><sub>D</sub> 1 μM). Development is ongoing to progress this lead into the first reported PCAF probe.</p>
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spelling oxford-uuid:a589d1f3-c8f6-4219-a10b-79099eafe1c82022-03-27T02:41:12ZDiscovery of epigenetic probes against the bromodomain family of proteinsThesishttp://purl.org/coar/resource_type/c_db06uuid:a589d1f3-c8f6-4219-a10b-79099eafe1c8Chemistry, MedicinalChemistry, OrganicEnglishORA Deposit2015Clark, PDixon, D<p>Chemical probes are necessary for elucidating the biochemical roles of proteins. Bromodomains are protein-interaction modules found in a family of proteins implicated in the epigenetic regulation of transcription; however, the individual roles remain unknown for many bromodomain proteins, without potent and selective ligands available to assist in their study. From lead compounds, a structure-based drug discovery program was to be explored with the use of biophysical assays and appropriate chemical methods to expediate development of probes against a number of these proteins. A fragment lead against BRD4 was developed into PNZ5, a potent (<em>K</em><sub>D</sub> 5 nM) BRD4 probe with a high ligand efficiency. Although enantioselective syntheses and the use of an alternative synthetic route were unsuccessful, PNZ5 showed cytotoxic activity against gastric cancer cell lines that had proved resilient to existing anticancer agents. Optimisation of a lead compound against BRD9 resulted in the development of LP99, the first reported BRD7/9 probe, that was potent (BRD9 <em>K</em><sub>D</sub> 99 nM, BRD7 <em>K</em><sub>D</sub> 909 nM), selective amongst bromodomain proteins and active in cells. An enantioselective synthesis was performed using chiral organocatalyts and LP99 was used to identify a previously unknown role of BRD7/9 in the regulation of inflammatory processes. Research is ongoing to assess further biochemical roles of these proteins with LP99. Arising from a more potent lead against BRD9, a series of structurally related compounds were synthesised to explore SAR around this ligand, however no improvement on the affinity of the lead was realised. Finally, based on disclosed lead structures against PCAF, a series of compounds were synthesised to replicate their activity. A number of important binding interactions were assessed and a lead structure was identified (<em>K</em><sub>D</sub> 1 μM). Development is ongoing to progress this lead into the first reported PCAF probe.</p>
spellingShingle Chemistry, Medicinal
Chemistry, Organic
Clark, P
Discovery of epigenetic probes against the bromodomain family of proteins
title Discovery of epigenetic probes against the bromodomain family of proteins
title_full Discovery of epigenetic probes against the bromodomain family of proteins
title_fullStr Discovery of epigenetic probes against the bromodomain family of proteins
title_full_unstemmed Discovery of epigenetic probes against the bromodomain family of proteins
title_short Discovery of epigenetic probes against the bromodomain family of proteins
title_sort discovery of epigenetic probes against the bromodomain family of proteins
topic Chemistry, Medicinal
Chemistry, Organic
work_keys_str_mv AT clarkp discoveryofepigeneticprobesagainstthebromodomainfamilyofproteins