2UWD

Inhibition of the HSP90 molecular chaperone in vitro and in vivo by novel, synthetic, potent resorcinylic pyrazole, isoxazole amide analogs


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.259 
  • R-Value Work: 0.201 
  • R-Value Observed: 0.204 

Starting Model: experimental
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Ligand Structure Quality Assessment 


This is version 1.4 of the entry. See complete history


Literature

Inhibition of the heat shock protein 90 molecular chaperone in vitro and in vivo by novel, synthetic, potent resorcinylic pyrazole/isoxazole amide analogues.

Sharp, S.Y.Prodromou, C.Boxall, K.Powers, M.V.Holmes, J.L.Box, G.Matthews, T.P.Cheung, K.M.Kalusa, A.James, K.Hayes, A.Hardcastle, A.Dymock, B.Brough, P.A.Barril, X.Cansfield, J.E.Wright, L.Surgenor, A.Foloppe, N.Hubbard, R.E.Aherne, W.Pearl, L.Jones, K.McDonald, E.Raynaud, F.Eccles, S.Drysdale, M.Workman, P.

(2007) Mol Cancer Ther 6: 1198-1211

  • DOI: https://doi.org/10.1158/1535-7163.MCT-07-0149
  • Primary Citation of Related Structures:  
    2UWD

  • PubMed Abstract: 

    Although the heat shock protein 90 (HSP90) inhibitor 17-allylamino-17-demethoxygeldanamycin (17-AAG) shows clinical promise, potential limitations encourage development of alternative chemotypes. We discovered the 3,4-diarylpyrazole resorcinol CCT018159 by high-throughput screening and used structure-based design to generate more potent pyrazole amide analogues, exemplified by VER-49009. Here, we describe the detailed biological properties of VER-49009 and the corresponding isoxazole VER-50589. X-ray crystallography showed a virtually identical HSP90 binding mode. However, the dissociation constant (K(d)) of VER-50589 was 4.5 +/- 2.2 nmol/L compared with 78.0 +/- 10.4 nmol/L for VER-49009, attributable to higher enthalpy for VER-50589 binding. A competitive binding assay gave a lower IC(50) of 21 +/- 4 nmol/L for VER-50589 compared with 47 +/- 9 nmol/L for VER-49009. Cellular uptake of VER-50589 was 4-fold greater than for VER-49009. Mean cellular antiproliferative GI(50) values for VER-50589 and VER-49009 for a human cancer cell line panel were 78 +/- 15 and 685 +/- 119 nmol/L, respectively, showing a 9-fold potency gain for the isoxazole. Unlike 17-AAG, but as with CCT018159, cellular potency of these analogues was independent of NAD(P)H:quinone oxidoreductase 1/DT-diaphorase and P-glycoprotein expression. Consistent with HSP90 inhibition, VER-50589 and VER-49009 caused induction of HSP72 and HSP27 alongside depletion of client proteins, including C-RAF, B-RAF, and survivin, and the protein arginine methyltransferase PRMT5. Both caused cell cycle arrest and apoptosis. Extent and duration of pharmacodynamic changes in an orthotopic human ovarian carcinoma model confirmed the superiority of VER-50589 over VER-49009. VER-50589 accumulated in HCT116 human colon cancer xenografts at levels above the cellular GI(50) for 24 h, resulting in 30% growth inhibition. The results indicate the therapeutic potential of the resorcinylic pyrazole/isoxazole amide analogues as HSP90 inhibitors.


  • Organizational Affiliation

    Cancer Research UK Centre for Cancer Therapeutics, The Institute of Cancer Research, Haddow Laboratories, Sutton, Surrey, United Kingdom.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
HEAT SHOCK PROTEIN HSP 90-ALPHA236Homo sapiensMutation(s): 0 
UniProt & NIH Common Fund Data Resources
Find proteins for P07900 (Homo sapiens)
Explore P07900 
Go to UniProtKB:  P07900
PHAROS:  P07900
GTEx:  ENSG00000080824 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP07900
Sequence Annotations
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  • Reference Sequence
Small Molecules
Binding Affinity Annotations 
IDSourceBinding Affinity
2GG PDBBind:  2UWD Kd: 4.5 (nM) from 1 assay(s)
BindingDB:  2UWD IC50: 28 (nM) from 1 assay(s)
EC50: 120 (nM) from 1 assay(s)
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.90 Å
  • R-Value Free: 0.259 
  • R-Value Work: 0.201 
  • R-Value Observed: 0.204 
  • Space Group: I 2 2 2
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 65.297α = 90
b = 88.683β = 90
c = 99.701γ = 90
Software Package:
Software NamePurpose
REFMACrefinement
d*TREKdata reduction
d*TREKdata scaling
AMoREphasing

Structure Validation

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Ligand Structure Quality Assessment 


Entry History 

Revision History  (Full details and data files)

  • Version 1.0: 2007-04-24
    Type: Initial release
  • Version 1.1: 2011-05-08
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance
  • Version 1.3: 2018-02-28
    Changes: Database references
  • Version 1.4: 2023-12-13
    Changes: Data collection, Database references, Derived calculations, Other, Refinement description