4BJX

N-TERMINAL BROMODOMAIN OF HUMAN BRD4 WITH GSK1324726A (I-BET726)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.59 Å
  • R-Value Free: 0.185 
  • R-Value Work: 0.157 
  • R-Value Observed: 0.158 

wwPDB Validation   3D Report Full Report


Ligand Structure Quality Assessment 


This is version 1.3 of the entry. See complete history


Literature

Bet Inhibition Silences Expression of Mycn and Bcl2 and Induces Cytotoxicity in Neuroblastoma Tumor Models.

Wyce, A.Ganji, G.Smitheman, K.N.Chung, C.Korenchuk, S.Bai, Y.Barbash, O.Le, B.Craggs, P.D.Mccabe, M.T.Kennedy-Wilson, K.M.Sanchez, L.V.Gosmini, R.L.Parr, N.Mchugh, C.F.Dhanak, D.Prinjha, R.K.Auger, K.R.Tummino, P.J.

(2013) PLoS One 8: 72967

  • DOI: https://doi.org/10.1371/journal.pone.0072967
  • Primary Citation of Related Structures:  
    4BJX

  • PubMed Abstract: 

    BET family proteins are epigenetic regulators known to control expression of genes involved in cell growth and oncogenesis. Selective inhibitors of BET proteins exhibit potent anti-proliferative activity in a number of hematologic cancer models, in part through suppression of the MYC oncogene and downstream Myc-driven pathways. However, little is currently known about the activity of BET inhibitors in solid tumor models, and whether down-regulation of MYC family genes contributes to sensitivity. Here we provide evidence for potent BET inhibitor activity in neuroblastoma, a pediatric solid tumor associated with a high frequency of MYCN amplifications. We treated a panel of neuroblastoma cell lines with a novel small molecule inhibitor of BET proteins, GSK1324726A (I-BET726), and observed potent growth inhibition and cytotoxicity in most cell lines irrespective of MYCN copy number or expression level. Gene expression analyses in neuroblastoma cell lines suggest a role of BET inhibition in apoptosis, signaling, and N-Myc-driven pathways, including the direct suppression of BCL2 and MYCN. Reversal of MYCN or BCL2 suppression reduces the potency of I-BET726-induced cytotoxicity in a cell line-specific manner; however, neither factor fully accounts for I-BET726 sensitivity. Oral administration of I-BET726 to mouse xenograft models of human neuroblastoma results in tumor growth inhibition and down-regulation MYCN and BCL2 expression, suggesting a potential role for these genes in tumor growth. Taken together, our data highlight the potential of BET inhibitors as novel therapeutics for neuroblastoma, and suggest that sensitivity is driven by pleiotropic effects on cell growth and apoptotic pathways in a context-specific manner.


  • Organizational Affiliation

    Cancer Epigenetics Discovery Performance Unit, GlaxoSmithKline, Collegeville, Pennsylvania, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
BROMODOMAIN-CONTAINING PROTEIN 4153Homo sapiensMutation(s): 0 
UniProt & NIH Common Fund Data Resources
Find proteins for O60885 (Homo sapiens)
Explore O60885 
Go to UniProtKB:  O60885
PHAROS:  O60885
GTEx:  ENSG00000141867 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupO60885
Sequence Annotations
Expand
  • Reference Sequence
Small Molecules
Ligands 1 Unique
IDChains Name / Formula / InChI Key2D Diagram3D Interactions
73B
Query on 73B

Download Ideal Coordinates CCD File 
B [auth A]4-[(2S,4R)-1-acetyl-4-[(4-chlorophenyl)amino]-2-methyl-1,2,3,4-tetrahydroquinolin-6-yl]benzoic acid
C25 H23 Cl N2 O3
FAWSUKOIROHXAP-NPMXOYFQSA-N
Binding Affinity Annotations 
IDSourceBinding Affinity
73B BindingDB:  4BJX Kd: min: 4.4, max: 23 (nM) from 2 assay(s)
IC50: min: 0.4, max: 501 (nM) from 6 assay(s)
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.59 Å
  • R-Value Free: 0.185 
  • R-Value Work: 0.157 
  • R-Value Observed: 0.158 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 44.78α = 90
b = 47.906β = 90
c = 58.757γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
XDSdata reduction
SCALAdata scaling

Structure Validation

View Full Validation Report



Ligand Structure Quality Assessment 


Entry History 

Deposition Data

  • Released Date: 2013-10-02 
  • Deposition Author(s): Chung, C.

Revision History  (Full details and data files)

  • Version 1.0: 2013-10-02
    Type: Initial release
  • Version 1.1: 2014-04-23
    Changes: Database references, Source and taxonomy
  • Version 1.2: 2019-05-15
    Changes: Data collection, Experimental preparation, Other
  • Version 1.3: 2024-05-08
    Changes: Data collection, Database references, Derived calculations, Other