2YI6

Structural characterization of 5-Aryl-4-(5-substituted-2-4- dihydroxyphenyl)-1,2,3-thiadiazole Hsp90 inhibitors.


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.238 
  • R-Value Work: 0.188 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Co-Crystalization and in Vitro Biological Characterization of 5-Aryl-4-(5-Substituted-2-4-Dihydroxyphenyl)-1,2,3-Thiadiazole Hsp90 Inhibitors.

Sharp, S.Y.Roe, S.M.Kazlauskas, E.Cikotiene, I.Workman, P.Matulis, D.Prodromou, C.

(2012) Plos One 7: 44642

  • DOI: 10.1371/journal.pone.0044642
  • Primary Citation of Related Structures:  2YI0, 2YI5, 2YI7

  • PubMed Abstract: 
  • A potential therapeutic strategy for targeting cancer that has gained much interest is the inhibition of the ATP binding and ATPase activity of the molecular chaperone Hsp90. We have determined the structure of the human Hsp90α N-terminal domain in c ...

    A potential therapeutic strategy for targeting cancer that has gained much interest is the inhibition of the ATP binding and ATPase activity of the molecular chaperone Hsp90. We have determined the structure of the human Hsp90α N-terminal domain in complex with a series of 5-aryl-4-(5-substituted-2-4-dihydroxyphenyl)-1,2,3-thiadiazoles. The structures provide the molecular details for the activity of these inhibitors. One of these inhibitors, ICPD 34, causes a structural change that affects a mobile loop, which adopts a conformation similar to that seen in complexes with ADP, rather than the conformation generally seen with the pyrazole/isoxazole-resorcinol class of inhibitors. Competitive binding to the Hsp90 N-terminal domain was observed in a biochemical assay, and these compounds showed antiproliferative activity and induced apoptosis in the HCT116 human colon cancer cell line. These inhibitors also caused induction of the heat shock response with the upregulation of Hsp72 and Hsp27 protein expression and the depletion of Hsp90 clients, CRAF, ERBB2 and CDK4, thus confirming that antiproliferative activity was through the inhibition of Hsp90. The presence of increased levels of the cleavage product of PARP indicated apoptosis in response to Hsp90 inhibitors. This work provides a framework for the further optimization of thiadiazole inhibitors of Hsp90. Importantly, we demonstrate that the thiadiazole inhibitors display a more limited core set of interactions relative to the clinical trial candidate NVP-AUY922, and consequently may be less susceptible to resistance derived through mutations in Hsp90.


    Organizational Affiliation

    Cancer Research UK Cancer Therapeutics Unit, Division of 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
229Homo sapiensGene Names: HSP90AA1 (HSP90A, HSPC1, HSPCA)
Find proteins for P07900 (Homo sapiens)
Go to Gene View: HSP90AA1
Go to UniProtKB:  P07900
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
MG
Query on MG

Download SDF File 
Download CCD File 
A
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
6QM
Query on 6QM

Download SDF File 
Download CCD File 
A
4-[5-(4-ETHOXYPHENYL)-1,2,3-THIADIAZOL-4-YL]-6-ETHYLBENZENE-1,3-DIOL
C18 H18 N2 O3 S
DUXCVYIPXRRATG-UHFFFAOYSA-N
 Ligand Interaction
External Ligand Annotations 
IDBinding Affinity (Sequence Identity %)
6QMKd: 42 nM (100) BINDINGDB
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.8 Å
  • R-Value Free: 0.238 
  • R-Value Work: 0.188 
  • Space Group: I 2 2 2
Unit Cell:
Length (Å)Angle (°)
a = 65.155α = 90.00
b = 88.830β = 90.00
c = 99.635γ = 90.00
Software Package:
Software NamePurpose
PHASERphasing
SCALAdata scaling
REFMACrefinement
MOSFLMdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2012-05-16
    Type: Initial release
  • Version 1.1: 2012-09-26
    Type: Database references