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: 1.9 Å
  • R-Value Free: 0.259 
  • R-Value Work: 0.201 

wwPDB Validation 3D Report Full Report


This is version 1.2 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.M.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

  • DOI: 10.1158/1535-7163.MCT-07-0149

  • 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 CCT018 ...

    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: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
HEAT SHOCK PROTEIN HSP 90-ALPHA
A
236Homo sapiensGene Names: HSP90AA1 (HSP90A, HSPC1, HSPCA)
Find proteins for P07900 (Homo sapiens)
Go to Gene View: HSP90AA1
Go to UniProtKB:  P07900
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
2GG
Query on 2GG

Download SDF File 
Download CCD File 
A
5-(5-CHLORO-2,4-DIHYDROXYPHENYL)-N-ETHYL-4-(4-METHOXYPHENYL)ISOXAZOLE-3-CARBOXAMIDE
C19 H17 Cl N2 O5
JXPCDMPJCKNLBY-UHFFFAOYSA-N
 Ligand Interaction
SO4
Query on SO4

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Download CCD File 
A
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
MG
Query on MG

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Download CCD File 
A
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
2GGEC50: 120 nM (92) BINDINGDB
2GGIC50: 28 nM (92) BINDINGDB
2GGKd: 4.5 nM BINDINGMOAD
2GGKd: 4.5 nM PDBBIND
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.259 
  • R-Value Work: 0.201 
  • Space Group: I 2 2 2
Unit Cell:
Length (Å)Angle (°)
a = 65.297α = 90.00
b = 88.683β = 90.00
c = 99.701γ = 90.00
Software Package:
Software NamePurpose
REFMACrefinement
AMoREphasing
d*TREKdata reduction
d*TREKdata scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Revision History 

  • Version 1.0: 2007-04-24
    Type: Initial release
  • Version 1.1: 2011-05-08
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance