Geldanamycin (SM55-250)

Geldanamycin is a natural existing HSP90 (Heat Schock Protein 90) inhibitor, specifically disrupts glucocorticoid receptor (GR)/HSP association. The HSP90 chaperone is required for the activation of several families of eukaryotic protein kinases and nuclear hormone receptors, many of which are proto-oncogenic and play a prominent role in cancer.