scholarly journals Synergism of Heat Shock Protein 90 and Histone Deacetylase Inhibitors in Synovial Sarcoma

Sarcoma ◽  
2009 ◽  
Vol 2009 ◽  
pp. 1-10 ◽  
Author(s):  
Anne Nguyen ◽  
Le Su ◽  
Belinda Campbell ◽  
Neal M. Poulin ◽  
Torsten O. Nielsen

Current systemic therapies have little curative benefit for synovial sarcoma. Histone deacetylase (HDAC) inhibitors and the heat shock protein 90 (Hsp90) inhibitor 17-AAG have recently been shown to inhibit synovial sarcoma in preclinical models. We tested combinations of 17-AAG with the HDAC inhibitor MS-275 for synergism by proliferation and apoptosis assays. The combination was found to be synergistic at multiple time points in two synovial sarcoma cell lines. Previous studies have shown that HDAC inhibitors not only induce cell death but also activate the survival pathway NF-κB, potentially limiting therapeutic benefit. As 17-AAG inhibits activators of NF-κB, we tested if 17-AAG synergizes with MS-275 through abrogating NF-κB activation. In our assays, adding 17-AAG blocks NF-κB activation by MS-275 and siRNA directed against histone deacetylase 3 (HDAC3) recapitulates the effects of MS-275. Additionally, we find that the NF-κB inhibitor BAY 11-7085 synergizes with MS-275. We conclude that agents inhibiting NF-κB synergize with HDAC inhibitors against synovial sarcoma.

2008 ◽  
Vol 294 (4) ◽  
pp. L755-L763 ◽  
Author(s):  
Anuran Chatterjee ◽  
Connie Snead ◽  
Gunay Yetik-Anacak ◽  
Galina Antonova ◽  
Jingmin Zeng ◽  
...  

Endothelial hyperperme ability leading to vascular leak is an important consequence of sepsis and sepsis-induced lung injury. We previously reported that heat shock protein (hsp) 90 inhibitor pretreatment improved pulmonary barrier dysfunction in a murine model of sepsis-induced lung injury. We now examine the effects of hsp90 inhibitors on LPS-mediated endothelial hyperpermeability, as reflected in changes in transendothelial electrical resistance (TER) of bovine pulmonary arterial endothelial cells (BPAEC). Vehicle-pretreated cells exposed to endotoxin exhibited a concentration-dependent decrease in TER, activation of pp60Src, phosphorylation of the focal adhesion protein paxillin, and reduced expression of the adherens junction proteins, vascular endothelial (VE)-cadherin and β-catenin. Pretreatment with the hsp90 inhibitor, radicicol, prevented the decrease in TER, maintained VE-cadherin and β-catenin expression, and inhibited activation of pp60Src and phosphorylation of paxillin. Similarly, when BPAEC hyperpermeability was induced by endotoxin-activated neutrophils, pretreatment of neutrophils and/or endothelial cells with radicicol protected against the activated neutrophil-induced decrease in TER. Increased paxillin phosphorylation and decreased expression of β-catenin and VE-cadherin were also observed in mouse lungs 12 h after intraperitoneal endotoxin and attenuated in mice pretreated with radicicol. These results suggest that hsp90 plays an important role in sepsis-associated endothelial barrier dysfunction.


2018 ◽  
Vol 293 (43) ◽  
pp. 16596-16607 ◽  
Author(s):  
Jackson B. Trotman ◽  
Bernice A. Agana ◽  
Andrew J. Giltmier ◽  
Vicki H. Wysocki ◽  
Daniel R. Schoenberg

The N7-methylguanosine cap is added in the nucleus early in gene transcription and is a defining feature of eukaryotic mRNAs. Mammalian cells also possess cytoplasmic machinery for restoring the cap at uncapped or partially degraded RNA 5′ ends. Central to both pathways is capping enzyme (CE) (RNA guanylyltransferase and 5′-phosphatase (RNGTT)), a bifunctional, nuclear and cytoplasmic enzyme. CE is recruited to the cytoplasmic capping complex by binding of a C-terminal proline-rich sequence to the third Src homology 3 (SH3) domain of NCK adapter protein 1 (NCK1). To gain broader insight into the cellular context of cytoplasmic recapping, here we identified the protein interactome of cytoplasmic CE in human U2OS cells through two complementary approaches: chemical cross-linking and recovery with cytoplasmic CE and protein screening with proximity-dependent biotin identification (BioID). This strategy unexpectedly identified 66 proteins, 52 of which are RNA-binding proteins. We found that CE interacts with several of these proteins independently of RNA, mediated by sequences within its N-terminal triphosphatase domain, and we present a model describing how CE-binding proteins may function in defining recapping targets. This analysis also revealed that CE is a client protein of heat shock protein 90 (HSP90). Nuclear and cytoplasmic CEs were exquisitely sensitive to inhibition of HSP90, with both forms declining significantly following treatment with each of several HSP90 inhibitors. Importantly, steady-state levels of capped mRNAs decreased in cells treated with the HSP90 inhibitor geldanamycin, raising the possibility that the cytotoxic effect of these drugs may partially be due to a general reduction in translatable mRNAs.


2021 ◽  
Vol 28 ◽  
Author(s):  
Davide Bonanni ◽  
Andrea Citarella ◽  
Davide Moi ◽  
Luca Pinzi ◽  
Elisa Bergamini ◽  
...  

: The design of multi-target drugs acting simultaneously on multiple signaling pathways is a growing field in medicinal chemistry, especially for the treatment of complex diseases such as cancer. Histone deacetylase 6 (HDAC6) is an established anticancer drug target involved in tumor cells transformation. Being an epigenetic enzyme at the interplay of many biological processes, HDAC6 has become an attractive target for polypharmacology studies aimed at improving therapeutic efficacy of anticancer drugs. For example, the molecular chaperone Heat shock protein 90 (Hsp90) is a substrate of HDAC6 deacetylation, and several lines of evidence demonstrate that simultaneous inhibition of HDAC6 and Hsp90 promote synergistic antitumor effects on different cancer cell lines, highlighting the potential benefits of developing a single molecule endowed with multi-target activity. This review will summarize the complex interplay between HDAC6 and Hsp90, providing also useful hints for multi-target drug design and discovery approaches in this field. To this end, crystallographic structures of HDAC6 and Hsp90 complexes will be extensively reviewed in the light of discussing binding pockets features and pharmacophore requirements and providing useful guidelines for the design of dual inhibitors. The few examples of multi-target inhibitors obtained so far, mostly based on chimeric approaches, will be summarized and put into context. Finally, the main features of HDAC6 and Hsp90 inhibitors will be compared, and ligand- and structure-based strategies potentially useful for the development of small molecular weight dual inhibitors will be proposed and discussed.


ACS Omega ◽  
2020 ◽  
Vol 5 (20) ◽  
pp. 11473-11480 ◽  
Author(s):  
Luca Pinzi ◽  
Rosaria Benedetti ◽  
Lucia Altucci ◽  
Giulio Rastelli

Blood ◽  
2007 ◽  
Vol 110 (2) ◽  
pp. 678-685 ◽  
Author(s):  
Cong Peng ◽  
Julia Brain ◽  
Yiguo Hu ◽  
Ami Goodrich ◽  
Linghong Kong ◽  
...  

Abstract Development of kinase domain mutations is a major drug-resistance mechanism for tyrosine kinase inhibitors (TKIs) in cancer therapy. A particularly challenging example is found in Philadelphia chromosome–positive chronic myelogenous leukemia (CML) where all available kinase inhibitors in clinic are ineffective against the BCR-ABL mutant, T315I. As an alternative approach to kinase inhibition, an orally administered heat shock protein 90 (Hsp90) inhibitor, IPI-504, was evaluated in a murine model of CML. Treatment with IPI-504 resulted in BCR-ABL protein degradation, decreased numbers of leukemia stem cells, and prolonged survival of leukemic mice bearing the T315I mutation. Hsp90 inhibition more potently suppressed T315I-expressing leukemia clones relative to the wild-type (WT) clones in mice. Combination treatment with IPI-504 and imatinib was more effective than either treatment alone in prolonging survival of mice simultaneously bearing both WT and T315I leukemic cells. These results provide a rationale for use of an Hsp90 inhibitor as a first-line treatment in CML by inhibiting leukemia stem cells and preventing the emergence of imatinib-resistant clones in patients. Rather than inhibiting kinase activity, elimination of mutant kinases provides a new therapeutic strategy for treating BCR-ABL–induced leukemia as well as other cancers resistant to treatment with tyrosine kinase inhibitors.


2019 ◽  
Vol 46 (10) ◽  
pp. 925
Author(s):  
Erina Matsuoka ◽  
Naoki Kato ◽  
Masakazu Hara

The heat shock protein 90 (HSP90) inhibitor, geldanamycin, is a chemical inducer of the heat shock response (HSR) in Arabidopsis. Geldanamycin is thought to activate the heat shock signal by dissociating the HSP90-heat shock factor (HSF) complex. Recent studies have indicated that plant HSP70 is also associated with HSF, suggesting that inhibition of HSP70 may induce the HSR. However, no studies have been conducted to test this hypothesis. Here, we found that a specific HSP70 inhibitor VER-155008 activated the promoter of a small HSP gene (At1 g53540, HSP17.6C-CI) of Arabidopsis, which was shown to be activated by geldanamycin and other HSP90 inhibitors. The production of HSP17.6C-CI, HSP70 and HSP90.1 proteins in Arabidopsis was enhanced by the addition of VER-155008. The reduction of chlorophyll contents by heat shock was ameliorated by VER-155008. Chaperone analyses indicated that VER-155008 inhibited the chaperone activities of wheat germ extract and human HSP70/HSP40, respectively. These results suggest that the inhibition of HSP70 by VER-155008 enhanced the heat tolerance of Arabidopsis by inducing the HSR in the plant.


Sign in / Sign up

Export Citation Format

Share Document