The aim of the present study was to determine the correlation between hepatocellular carcinoma (HCC) and heat shock protein 90 (HSP90), involved in tumor angiogenesis, and to evaluate the effect of AUY922, a HSP90 inhibitor, in HCC. The expression of HSP90 and microvessel density (MVD) were measured in tissue samples from 76 patients with HCC by immunohistochemistry. Western blot analysis was p...

Structurally related tetratricopeptide repeat motifs in steroid receptor-associated immunophilins and the STI1 homolog, Hop, mediate the interaction with a common cellular target, hsp90. We have identified the binding domain in hsp90 for cyclophilin 40 (CyP40) using a two-hybrid system screen of a mouse cDNA library. All isolated clones encoded the intact carboxyl terminus of hsp90 and overlapp...

The action of the molecular chaperone Hsp90 is essential for the activation and assembly of an increasing number of client proteins. This function of Hsp90 has been proposed to be governed by conformational changes driven by ATP binding and hydrolysis. Association of co-chaperones and client proteins regulate the ATPase activity of Hsp90. Here, we have examined the inhibition of the ATPase acti...

PURPOSE Histone deacetylase 6 (HDAC6) is an enzyme that deacetylates heat-shock protein 90 (HSP90). Many studies have investigated the role of HDAC6 and HSP90 in tumorigenesis and in the prognosis of cancer patients. This study aimed to evaluate the prognostic value of HDAC6 and acetylated HSP90 (acetyl-HSP90) in a cohort of breast cancer patients. METHODS Immunohistochemical analysis of 314 ...

Hsp90, an evolutionarily conserved molecular chaperone, is involved in the folding, stabilization, activation, and assembly of a wide range of 'client' proteins, thus playing a central role in many biological processes. Especially, several oncoproteins act as Hsp90 client proteins and tumor cells require higher Hsp90 activity than normal cells to maintain their malignancy. For this reason, Hsp9...

The development of lethal, castration resistant prostate cancer is associated with adaptive changes to the androgen receptor (AR), including the emergence of mutant receptors and truncated, constitutively active AR variants. AR relies on the molecular chaperone HSP90 for its function in both normal and malignant prostate cells, but the requirement for HSP90 in environments with aberrant AR expr...

Introduction Hsp90 (heat-shock protein 90) is an abundant molecular chaperone, but its function seems to be restricted to the folding of proteins involved in cell signalling, such as transcription factors and protein kinases. This restricted set of ‘clients’ (see Fig. 1) makes Hsp90 an attractive target for cancer therapeutics. As an anti-Hsp90 drug is now in clinical trials, the meeting was re...

Protein phosphatase 5 is involved in the regulation of kinases and transcription factors. The dephosphorylation activity is modulated by the molecular chaperone Hsp90, which binds to the TPR-domain of protein phosphatase 5. This interaction is dependent on the C-terminal MEEVD motif of Hsp90. We show that C-terminal Hsp90 fragments differ in their regulation of the phosphatase activity hinting ...

HSP90 is an essential heat shock protein found in all eukaryotes studied so far. This protein is known for its role in facilitating maturation of signaling molecules, manage protein folding, cell cycle control, protein degradation and protein trafficking. In plants HSP90 is localized in cytosol, chloroplast, mitochondria and ER. In present investigation an amplicon of ~2.5 kb was amplified from...

Heat shock protein 90 (Hsp90) is a promising cancer drug target as a molecular chaperone critical for stabilization and activation of several of the oncoproteins that drive cancer progression. Its actions depend upon its essential ATPase, an activity fortuitously inhibited with a very high degree of selectivity by natural antibiotics: notably the actinomycete-derived benzoquinone ansamycins (e....