title: Potent and selective bivalent inhibitors of BET bromodomains.
abstract: Proteins of the bromodomain and extraterminal (BET) family, in particular bromodomain-containing protein 4 (BRD4), are of great interest as biological targets. BET proteins contain two separate bromodomains, and existing inhibitors bind to them monovalently. Here we describe the discovery and characterization of probe compound biBET, capable of engaging both bromodomains simultaneously in a bivalent, in cis binding mode. The evidence provided here was obtained in a variety of biophysical and cellular experiments. The bivalent binding results in very high cellular potency for BRD4 binding and pharmacological responses such as disruption of BRD4-mediator complex subunit 1 foci with an EC50of 100 pM. These compounds will be of considerable utility as BET/BRD4 chemical probes. This work illustrates a novel concept in ligand design-simultaneous targeting of two separate domains with a drug-like small molecule-providing precedent for a potentially more effective paradigm for developing ligands for other multi-domain proteins.
authors: AstraZeneca, Alderley Park, UK.|Northern Institute for Cancer Research, School of Chemistry, Newcastle University, Newcastle upon Tyne, UK.
authors: Michael J
authors: MJ
authors: Waring
authors: AstraZeneca, Waltham, Massachusetts, USA.
authors: Huawei
authors: H
authors: Chen
authors: AstraZeneca, Alderley Park, UK.
authors: Alfred A
authors: AA
authors: Rabow
authors: AstraZeneca, Alderley Park, UK.
authors: Graeme
authors: G
authors: Walker
authors: AstraZeneca, Alderley Park, UK.
authors: Romel
authors: http://orcid.org/0000-0001-5652-4098
authors: R
authors: Bobby
authors: AstraZeneca, Waltham, Massachusetts, USA.
authors: Scott
authors: S
authors: Boiko
authors: AstraZeneca, Alderley Park, UK.
authors: Rob H
authors: RH
authors: Bradbury
authors: AstraZeneca, Alderley Park, UK.
authors: Rowena
authors: R
authors: Callis
authors: AstraZeneca, Waltham, Massachusetts, USA.
authors: Edwin
authors: E
authors: Clark
authors: AstraZeneca, Alderley Park, UK.
authors: Ian
authors: I
authors: Dale
authors: Promega Corporation, Madison, Wisconsin, USA.
authors: Danette L
authors: DL
authors: Daniels
authors: AstraZeneca, Waltham, Massachusetts, USA.
authors: Austin
authors: A
authors: Dulak
authors: AstraZeneca, Alderley Park, UK.
authors: Liz
authors: L
authors: Flavell
authors: AstraZeneca, Alderley Park, UK.
authors: Geoff
authors: G
authors: Holdgate
authors: Wellcome Trust Centre for Cell-Matrix Research, University of Manchester, Manchester, UK.
authors: Thomas A
authors: TA
authors: Jowitt
authors: European Molecular Biology Laboratory, Hamburg, Germany.
authors: Alexey
authors: http://orcid.org/0000-0003-1321-3956
authors: A
authors: Kikhney
authors: AstraZeneca, Alderley Park, UK.
authors: Mark
authors: M
authors: McAlister
authors: Promega Corporation, Madison, Wisconsin, USA.
authors: Jacqui
authors: J
authors: Méndez
authors: AstraZeneca, Alderley Park, UK.
authors: Derek
authors: D
authors: Ogg
authors: AstraZeneca, Waltham, Massachusetts, USA.
authors: Joe
authors: J
authors: Patel
authors: AstraZeneca, Waltham, Massachusetts, USA.
authors: Philip
authors: P
authors: Petteruti
authors: AstraZeneca, Alderley Park, UK.
authors: Graeme R
authors: GR
authors: Robb
authors: Promega Corporation, Madison, Wisconsin, USA.
authors: Matthew B
authors: MB
authors: Robers
authors: AstraZeneca, Waltham, Massachusetts, USA.
authors: Sakina
authors: S
authors: Saif
authors: AstraZeneca, Alderley Park, UK.
authors: Natalie
authors: N
authors: Stratton
authors: European Molecular Biology Laboratory, Hamburg, Germany.
authors: Dmitri I
authors: DI
authors: Svergun
authors: AstraZeneca, Waltham, Massachusetts, USA.
authors: Wenxian
authors: W
authors: Wang
authors: AstraZeneca, Alderley Park, UK.
authors: David
authors: D
authors: Whittaker
authors: AstraZeneca, Alderley Park, UK.
authors: David M
authors: DM
authors: Wilson
authors: AstraZeneca, Waltham, Massachusetts, USA.
authors: Yi
authors: Y
authors: Yao
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D018797:Cell Cycle Proteins; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D018360:Crystallography, X-Ray; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008024:Ligands; D008958:Models, Molecular; D015394:Molecular Structure; D009687:Nuclear Proteins / Q000037:antagonists & inhibitors* / Q000737:chemistry* / Q000378:metabolism; D000072417:Protein Domains / Q000187:drug effects*; D054852:Small Molecule Libraries / Q000737:chemistry / Q000494:pharmacology*; D013329:Structure-Activity Relationship; D013379:Substrate Specificity; D014157:Transcription Factors / Q000037:antagonists & inhibitors* / Q000737:chemistry* / Q000378:metabolism; D000092468:Bromodomain Containing Proteins
chemical_list: D018797:Cell Cycle Proteins; D008024:Ligands; D009687:Nuclear Proteins; D054852:Small Molecule Libraries; D014157:Transcription Factors; C441289:BRD4 protein, human; D000092468:Bromodomain Containing Proteins