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Wang J, Yang C, Xu H, Fan X, Jia L, Du Y, Liu S, Wang W, Zhang J, Zhang Y, Wang X, Liu Z, Bao J, Li S, Yang J, Wu C, Tang J, Chen G, Wang L. The Interplay Between HIF-1α and EZH2 in Lung Cancer and Dual-Targeted Drug Therapy. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2024; 11:e2303904. [PMID: 38072662 PMCID: PMC10870044 DOI: 10.1002/advs.202303904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Revised: 10/26/2023] [Indexed: 02/17/2024]
Abstract
Interactions between oncogenic proteins contribute to the phenotype and drug resistance. Here, EZH2 (enhancer of zest homolog 2) is identified as a crucial factor that mediates HIF-1 (hypoxia-inducible factor) inhibitor resistance. Mechanistically, targeting HIF-1 enhanced the activity of EZH2 through transcription activation of SUZ12 (suppressor of zest 12 protein homolog). Conversely, inhibiting EZH2 increased HIF-1α transcription, but not the transcription of other HIF family members. Additionally, the negative feedback regulation between EZH2 and HIF-1α is confirmed in lung cancer patient tissues and a database of cell lines. Moreover, molecular prediction showed that a newly screened dual-target compound, DYB-03, forms multiple hydrogen bonds with HIF-1α and EZH2 to effectively inhibit the activity of both targets. Subsequent studies revealed that DYB-03 could better inhibit migration, invasion, and angiogenesis of lung cancer cells and HUVECs in vitro and in vivo compared to single agent. DYB-03 showed promising antitumor activity in a xenograft tumor model by promoting apoptosis and inhibiting angiogenesis, which could be almost abolished by the deletion of HIF-1α and EZH2. Notably, DYB-03 could reverse 2-ME2 and GSK126-resistance in lung cancer. These findings clarified the molecular mechanism of cross-regulation of HIF-1α and EZH2, and the potential of DYB-03 for clinical combination target therapy.
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Affiliation(s)
- Jianmin Wang
- School of Life Science and BiopharmaceuticsShenyang Pharmaceutical UniversityShenyang110016P. R. China
- Benxi Institute of Pharmaceutical ResearchShenyang Pharmaceutical UniversityBenxi117004P. R. China
| | - Cheng Yang
- School of Life Science and BiopharmaceuticsShenyang Pharmaceutical UniversityShenyang110016P. R. China
- Benxi Institute of Pharmaceutical ResearchShenyang Pharmaceutical UniversityBenxi117004P. R. China
| | - Huashen Xu
- Key Laboratory of Structure‐Based Drug Design & Discovery of Ministry of EducationSchool of Pharmaceutical EngineeringShenyang Pharmaceutical UniversityShenyang110016P. R. China
| | - Xinyu Fan
- Department of PharmacyShengjing Hospital of China Medical UniversityShenyang110004P. R. China
| | - Lina Jia
- School of Life Science and BiopharmaceuticsShenyang Pharmaceutical UniversityShenyang110016P. R. China
- Benxi Institute of Pharmaceutical ResearchShenyang Pharmaceutical UniversityBenxi117004P. R. China
| | - Yang Du
- Key Laboratory of Structure‐Based Drug Design & Discovery of Ministry of EducationSchool of Pharmaceutical EngineeringShenyang Pharmaceutical UniversityShenyang110016P. R. China
| | - Shougeng Liu
- School of Life Science and BiopharmaceuticsShenyang Pharmaceutical UniversityShenyang110016P. R. China
- Benxi Institute of Pharmaceutical ResearchShenyang Pharmaceutical UniversityBenxi117004P. R. China
| | - Wenjing Wang
- School of Life Science and BiopharmaceuticsShenyang Pharmaceutical UniversityShenyang110016P. R. China
- Benxi Institute of Pharmaceutical ResearchShenyang Pharmaceutical UniversityBenxi117004P. R. China
| | - Jie Zhang
- School of Life Science and BiopharmaceuticsShenyang Pharmaceutical UniversityShenyang110016P. R. China
- Benxi Institute of Pharmaceutical ResearchShenyang Pharmaceutical UniversityBenxi117004P. R. China
| | - Yu Zhang
- School of Life Science and BiopharmaceuticsShenyang Pharmaceutical UniversityShenyang110016P. R. China
- Benxi Institute of Pharmaceutical ResearchShenyang Pharmaceutical UniversityBenxi117004P. R. China
| | - Xiaoxue Wang
- School of Life Science and BiopharmaceuticsShenyang Pharmaceutical UniversityShenyang110016P. R. China
- Benxi Institute of Pharmaceutical ResearchShenyang Pharmaceutical UniversityBenxi117004P. R. China
| | - Zhongbo Liu
- School of PharmacyShenyang Pharmaceutical UniversityShenyang110016P. R. China
| | - Jie Bao
- Research Program in Systems OncologyFaculty of MedicineUniversity of HelsinkiHelsinki00290Finland
| | - Songping Li
- School of Life Science and BiopharmaceuticsShenyang Pharmaceutical UniversityShenyang110016P. R. China
| | - Jingyu Yang
- School of Life Science and BiopharmaceuticsShenyang Pharmaceutical UniversityShenyang110016P. R. China
- Benxi Institute of Pharmaceutical ResearchShenyang Pharmaceutical UniversityBenxi117004P. R. China
| | - Chunfu Wu
- School of Life Science and BiopharmaceuticsShenyang Pharmaceutical UniversityShenyang110016P. R. China
- Benxi Institute of Pharmaceutical ResearchShenyang Pharmaceutical UniversityBenxi117004P. R. China
| | - Jing Tang
- Research Program in Systems OncologyFaculty of MedicineUniversity of HelsinkiHelsinki00290Finland
| | - Guoliang Chen
- Key Laboratory of Structure‐Based Drug Design & Discovery of Ministry of EducationSchool of Pharmaceutical EngineeringShenyang Pharmaceutical UniversityShenyang110016P. R. China
| | - Lihui Wang
- School of Life Science and BiopharmaceuticsShenyang Pharmaceutical UniversityShenyang110016P. R. China
- Benxi Institute of Pharmaceutical ResearchShenyang Pharmaceutical UniversityBenxi117004P. R. China
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2
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Shin SY, Centenera MM, Hodgson JT, Nguyen EV, Butler LM, Daly RJ, Nguyen LK. A Boolean-based machine learning framework identifies predictive biomarkers of HSP90-targeted therapy response in prostate cancer. Front Mol Biosci 2023; 10:1094321. [PMID: 36743211 PMCID: PMC9892654 DOI: 10.3389/fmolb.2023.1094321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 01/06/2023] [Indexed: 01/20/2023] Open
Abstract
Precision medicine has emerged as an important paradigm in oncology, driven by the significant heterogeneity of individual patients' tumour. A key prerequisite for effective implementation of precision oncology is the development of companion biomarkers that can predict response to anti-cancer therapies and guide patient selection for clinical trials and/or treatment. However, reliable predictive biomarkers are currently lacking for many anti-cancer therapies, hampering their clinical application. Here, we developed a novel machine learning-based framework to derive predictive multi-gene biomarker panels and associated expression signatures that accurately predict cancer drug sensitivity. We demonstrated the power of the approach by applying it to identify response biomarker panels for an Hsp90-based therapy in prostate cancer, using proteomic data profiled from prostate cancer patient-derived explants. Our approach employs a rational feature section strategy to maximise model performance, and innovatively utilizes Boolean algebra methods to derive specific expression signatures of the marker proteins. Given suitable data for model training, the approach is also applicable to other cancer drug agents in different tumour settings.
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Affiliation(s)
- Sung-Young Shin
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia
- Cancer Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Margaret M. Centenera
- South Australian Immunogenomics Cancer Institute and Freemasons Foundation Centre for Men’s Health, University of Adelaide, Adelaide, SA, Australia
- South Australian Health and Medical Research Institute, Adelaide, SA, Australia
| | - Joshua T. Hodgson
- South Australian Immunogenomics Cancer Institute and Freemasons Foundation Centre for Men’s Health, University of Adelaide, Adelaide, SA, Australia
- South Australian Health and Medical Research Institute, Adelaide, SA, Australia
| | - Elizabeth V. Nguyen
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia
- Cancer Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Lisa M. Butler
- South Australian Immunogenomics Cancer Institute and Freemasons Foundation Centre for Men’s Health, University of Adelaide, Adelaide, SA, Australia
- South Australian Health and Medical Research Institute, Adelaide, SA, Australia
| | - Roger J. Daly
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia
- Cancer Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
| | - Lan K. Nguyen
- Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia
- Cancer Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC, Australia
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Abstract
The total synthesis of geldanamycin, a well-known polyketide that exhibited potent anticancer activity by inhibiting Hsp90, was finished in 26 long linear steps with 2.65% overall yield. High convergency of the synthesis was achieved by the disconnection between C12 and C13 that gives C5-C12 and C13-C21 fragments as major building blocks. The use of an alkynyl ketone as the precursor of the C5-C12 fragment enabled a reagent-controlled establishment of C7 chirality and a highly flexible substituent exchange at C8, making the synthetic route suitable for deep-seated structural modifications on geldanamycin.
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Affiliation(s)
- Zhi Zhang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicine, Institute of Materia Medica, Peking Union Medical College & Chinese Academy of Medical Sciences, No. 1 Xiannongtan Street, Beijing 100050, China
| | - Yunfeng Li
- State Key Laboratory of Bioactive Substance and Function of Natural Medicine, Institute of Materia Medica, Peking Union Medical College & Chinese Academy of Medical Sciences, No. 1 Xiannongtan Street, Beijing 100050, China
| | - Rentao Zhang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicine, Institute of Materia Medica, Peking Union Medical College & Chinese Academy of Medical Sciences, No. 1 Xiannongtan Street, Beijing 100050, China
| | - Xiaoming Yu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicine, Institute of Materia Medica, Peking Union Medical College & Chinese Academy of Medical Sciences, No. 1 Xiannongtan Street, Beijing 100050, China
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4
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Single-cell RNA sequencing reveals that targeting HSP90 suppresses PDAC progression by restraining mitochondrial bioenergetics. Oncogenesis 2021; 10:22. [PMID: 33658487 PMCID: PMC7930118 DOI: 10.1038/s41389-021-00311-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2020] [Revised: 02/08/2021] [Accepted: 02/10/2021] [Indexed: 12/15/2022] Open
Abstract
Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest cancers, which lacks effective treatment strategies. There is an urgent need for the development of new strategies for PDAC therapy. The genetic and phenotypic heterogeneity of PDAC cancer cell populations poses further challenges in the clinical management of PDAC. In this study, we performed single-cell RNA sequencing to characterize PDAC tumors from KPC mice. Functional studies and clinical analysis showed that PDAC cluster 2 cells with highly Hsp90 expression is much more aggressive than the other clusters. Genetic and pharmacologic inhibition of Hsp90 impaired tumor cell growth both in vitro and in vivo. Further mechanistic study revealed that HSP90 inhibition disrupted the interaction between HSP90 and OPA1, leading to a reduction in mitochondrial cristae amount and mitochondrial energy production. Collectively, our study reveals that HSP90 might be a potential therapeutic target for PDAC.
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Zhang Z, Xue N, Bian C, Yan R, Jin L, Chen X, Yu X. C15-methoxyphenylated 18-deoxy-herbimycin A analogues, their in vitro anticancer activity and heat shock protein 90 binding affinity. Bioorg Med Chem Lett 2016; 26:4287-91. [PMID: 27476419 DOI: 10.1016/j.bmcl.2016.07.040] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2016] [Revised: 07/11/2016] [Accepted: 07/19/2016] [Indexed: 11/30/2022]
Abstract
Benzoquinone ansamycins are important leads for the discovery of novel inhibitors of heat shock protein 90 (Hsp90), a promising target of cancer chemotherapeutics. Intrinsic hepatotoxicity caused by the benzoquinone moiety appeared to be a serious limitation to the development of these compounds. To solve this problem by rational structure optimization, a short series of C18-deoxy analogues of herbimycin A were designed based on putative interactions between the compound and the protein. Chemical synthesis of the target molecules were attempted by following the established synthetic route to the natural product, but resulted in the isolation of four serendipitous C15 phenylated final products. In vitro antiproliferative activity and Hsp90 binding affinity of the compounds were determined, suggesting the C18-oxygen of herbimycin A is removable and bulky lipophilic groups can be accommodated at C15 without loss of activity.
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Affiliation(s)
- Zhi Zhang
- State Key Laboratory of Bioactive Substance and Function of Natural Medicine, Institute of Materia Medica, Peking Union Medical College & Chinese Academy of Medical Sciences, No. 1 Xiannongtan Street, Beijing 100050, China
| | - Nina Xue
- State Key Laboratory of Bioactive Substance and Function of Natural Medicine, Institute of Materia Medica, Peking Union Medical College & Chinese Academy of Medical Sciences, No. 1 Xiannongtan Street, Beijing 100050, China
| | - Chuancai Bian
- State Key Laboratory of Bioactive Substance and Function of Natural Medicine, Institute of Materia Medica, Peking Union Medical College & Chinese Academy of Medical Sciences, No. 1 Xiannongtan Street, Beijing 100050, China
| | - Rui Yan
- State Key Laboratory of Bioactive Substance and Function of Natural Medicine, Institute of Materia Medica, Peking Union Medical College & Chinese Academy of Medical Sciences, No. 1 Xiannongtan Street, Beijing 100050, China
| | - Longlong Jin
- State Key Laboratory of Bioactive Substance and Function of Natural Medicine, Institute of Materia Medica, Peking Union Medical College & Chinese Academy of Medical Sciences, No. 1 Xiannongtan Street, Beijing 100050, China
| | - Xiaoguang Chen
- State Key Laboratory of Bioactive Substance and Function of Natural Medicine, Institute of Materia Medica, Peking Union Medical College & Chinese Academy of Medical Sciences, No. 1 Xiannongtan Street, Beijing 100050, China.
| | - Xiaoming Yu
- State Key Laboratory of Bioactive Substance and Function of Natural Medicine, Institute of Materia Medica, Peking Union Medical College & Chinese Academy of Medical Sciences, No. 1 Xiannongtan Street, Beijing 100050, China.
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6
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Wang H, Lu M, Yao M, Zhu W. Effects of treatment with an Hsp90 inhibitor in tumors based on 15 phase II clinical trials. Mol Clin Oncol 2016; 5:326-334. [PMID: 27602225 DOI: 10.3892/mco.2016.963] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 07/01/2016] [Indexed: 01/05/2023] Open
Abstract
Heat shock protein (Hsp)90 serves as a chaperone protein that promotes the proper folding of proteins involved in a variety of signal transduction processes involved in cell growth. Hsp90 inhibitors, which inhibit the activity of critical client proteins, have emerged as the accessory therapeutic agents for multiple human cancer types. To better understand the effects of Hsp90 inhibitors in cancer treatment, the present study reviewed 15 published phase II clinical trials to investigate whether Hsp90 inhibitors will benefit patients with cancer. Information of complete response, partial response, stable disease, objective response and objective response rate was collected to evaluate clinical outcomes. Overall, Hsp90 inhibitors are effective against a variety of oncogene-addicted cancers, including those that have developed resistance to specific receptors.
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Affiliation(s)
- He Wang
- Department of Oncology, The Third Affiliated Hospital of Nanjing Medical University, Nanjing 211100, P.R. China
| | - Mingjie Lu
- Department of Oncology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, P.R. China
| | - Mengqian Yao
- Department of Oncology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, P.R. China
| | - Wei Zhu
- Department of Oncology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, P.R. China
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7
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Pennisi R, Ascenzi P, di Masi A. Hsp90: A New Player in DNA Repair? Biomolecules 2015; 5:2589-618. [PMID: 26501335 PMCID: PMC4693249 DOI: 10.3390/biom5042589] [Citation(s) in RCA: 78] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 09/08/2015] [Accepted: 09/10/2015] [Indexed: 12/21/2022] Open
Abstract
Heat shock protein 90 (Hsp90) is an evolutionary conserved molecular chaperone that, together with Hsp70 and co-chaperones makes up the Hsp90 chaperone machinery, stabilizing and activating more than 200 proteins, involved in protein homeostasis (i.e., proteostasis), transcriptional regulation, chromatin remodeling, and DNA repair. Cells respond to DNA damage by activating complex DNA damage response (DDR) pathways that include: (i) cell cycle arrest; (ii) transcriptional and post-translational activation of a subset of genes, including those associated with DNA repair; and (iii) triggering of programmed cell death. The efficacy of the DDR pathways is influenced by the nuclear levels of DNA repair proteins, which are regulated by balancing between protein synthesis and degradation as well as by nuclear import and export. The inability to respond properly to either DNA damage or to DNA repair leads to genetic instability, which in turn may enhance the rate of cancer development. Multiple components of the DNA double strand breaks repair machinery, including BRCA1, BRCA2, CHK1, DNA-PKcs, FANCA, and the MRE11/RAD50/NBN complex, have been described to be client proteins of Hsp90, which acts as a regulator of the diverse DDR pathways. Inhibition of Hsp90 actions leads to the altered localization and stabilization of DDR proteins after DNA damage and may represent a cell-specific and tumor-selective radiosensibilizer. Here, the role of Hsp90-dependent molecular mechanisms involved in cancer onset and in the maintenance of the genome integrity is discussed and highlighted.
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Affiliation(s)
- Rosa Pennisi
- Department of Sciences, Roma Tre University, Viale Guglielmo Marconi 446, Roma I-00146, Italy.
| | - Paolo Ascenzi
- Department of Sciences, Roma Tre University, Viale Guglielmo Marconi 446, Roma I-00146, Italy.
- Istituto Nazionale di Biostrutture e Biosistemi, Viale Medaglie d'Oro 305, Roma I-00136, Italy.
| | - Alessandra di Masi
- Department of Sciences, Roma Tre University, Viale Guglielmo Marconi 446, Roma I-00146, Italy.
- Istituto Nazionale di Biostrutture e Biosistemi, Viale Medaglie d'Oro 305, Roma I-00136, Italy.
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Hsueh YS, Chang HH, Chiang NJ, Yen CC, Li CF, Chen LT. MTOR inhibition enhances NVP-AUY922-induced autophagy-mediated KIT degradation and cytotoxicity in imatinib-resistant gastrointestinal stromal tumors. Oncotarget 2015; 5:11723-36. [PMID: 25375091 PMCID: PMC4294368 DOI: 10.18632/oncotarget.2607] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 10/21/2014] [Indexed: 01/16/2023] Open
Abstract
Our previous study demonstrated NVP-AUY922, a HSP90AA1 inhibitor, could enhance mutant KIT degradation in gastrointestinal stromal tumor (GIST) cells through both proteasome- and autophagy-mediated pathways. Herein, we showed rapamycin, a MTOR inhibitor and autophagy inducer, could reduce total and phospho-KIT expression levels and enhance apoptosis in imatinib-resistant GIST cells. The involvement of autophagy in rapamycin-induced KIT downregulation was further confirmed by co-localization of KIT and autophagosome, and partial recovery of KIT expression level by either siRNA-mediated BECN1 and ATG5 silencing or autophagy inhibitors after rapamycin. Rapamycin and NVP-AUY922 synergistically inhibited GIST cells growth in vitro. The combination of low-dose NVP-AUY922 with rapamycin had comparable effects on reducing KIT expression, increasing MAP1LC3B puncta and tumor necrosis, and inhibiting tumor growth as high-dose NVP-AUY922 did in GIST430 xenograft model. Our results suggest the addition of a MTOR inhibitor may reduce NVP-AUY922 dose requirement and potentially improve its therapeutic index in mutant KIT-expressing GISTs.
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Affiliation(s)
- Yuan-Shuo Hsueh
- National Institute of Cancer Research, National Health Research Institutes, Tainan, Taiwan
| | - Hui Hua Chang
- Institute of Clinical Pharmacy and Pharmaceutical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan
| | - Nai-Jung Chiang
- National Institute of Cancer Research, National Health Research Institutes, Tainan, Taiwan. Department of Internal Medicine, National Cheng Kung University Hospital, Tainan, Taiwan
| | - Chueh-Chuan Yen
- Division of Hematology and Oncology, Department of Medicine, Taipei Veterans General Hospital, Taipei, Taiwan. National Yang-Ming University School of Medicine, Taipei, Taiwan
| | - Chien-Feng Li
- National Institute of Cancer Research, National Health Research Institutes, Tainan, Taiwan. Department of Pathology, Chi-Mei Foundation Medical Center, Tainan, Taiwan. Department of Biotechnology, Southern Taiwan University of Science and Technology, Tainan, Taiwan. Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Li-Tzong Chen
- National Institute of Cancer Research, National Health Research Institutes, Tainan, Taiwan. Institute of Clinical Pharmacy and Pharmaceutical Sciences, College of Medicine, National Cheng Kung University, Tainan, Taiwan. Department of Internal Medicine, National Cheng Kung University Hospital, Tainan, Taiwan. Department of Internal Medicine, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwann
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9
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Ku S, Lasorsa E, Adelaiye R, Ramakrishnan S, Ellis L, Pili R. Inhibition of Hsp90 augments docetaxel therapy in castrate resistant prostate cancer. PLoS One 2014; 9:e103680. [PMID: 25072314 PMCID: PMC4114978 DOI: 10.1371/journal.pone.0103680] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Accepted: 07/06/2014] [Indexed: 11/18/2022] Open
Abstract
First line treatment of patients with castrate resistant prostate cancer (CRPC) primarily involves administration of docetaxel chemotherapy. Unfortunately, resistance to docetaxel therapy is an ultimate occurrence. Alterations in androgen receptor (AR) expression and signaling are associated mechanisms underlying resistance to docetaxel treatment in CRPC. Heat shock protein 90 (Hsp90) is a molecular chaperone, which regulates the activation, maturation and stability of critical signaling proteins involved in prostate cancer, including the AR. This knowledge and recent advances in compound design and development have highlighted Hsp90 as an attractive therapeutic target for the treatment of CRPC. We recently reported the development of a MYC-CaP castrate resistant (MYC-CaP/CR) transplant tumor model, which expresses amplified wild type AR. Within, we report that a second generation Hsp90 inhibitor, NVP-AUY922, inhibits cell growth and significantly induces cell death in MYC-CaP/CR and Pten-CaP/cE2 cell lines. NVP-AUY922 induced proteasome degradation of AR, though interestingly does not require loss of AR protein to inhibit AR transcriptional activity. Further, NVP-AUY922 increased docetaxel toxicity in MYC-CaP/CR and Pten-CaP/cE2 cell lines in vitro. Finally, NVP-AUY922/docetaxel combination therapy in mice bearing MYC-CaP/CR tumors resulted in greater anti-tumor activity compared to single treatment. This study demonstrates that NVP-AUY922 elicits potent activity towards AR signaling and augments chemotherapy response in a mouse model of CRPC, providing rationale for the continued clinical development of Hsp90 inhibitors in clinical trials for treatment of CRPC patients.
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MESH Headings
- Animals
- Antineoplastic Agents/pharmacology
- Antineoplastic Agents/therapeutic use
- Apoptosis/drug effects
- Cell Line, Tumor
- Cell Proliferation/drug effects
- Docetaxel
- Drug Resistance, Neoplasm
- Drug Therapy, Combination
- HSP90 Heat-Shock Proteins/antagonists & inhibitors
- HSP90 Heat-Shock Proteins/metabolism
- Isoxazoles/pharmacology
- Isoxazoles/therapeutic use
- Male
- Mice
- Mice, SCID
- Prostatic Neoplasms, Castration-Resistant/drug therapy
- Prostatic Neoplasms, Castration-Resistant/pathology
- Proteasome Endopeptidase Complex/metabolism
- Receptors, Androgen/genetics
- Receptors, Androgen/metabolism
- Resorcinols/pharmacology
- Resorcinols/therapeutic use
- Taxoids/pharmacology
- Taxoids/therapeutic use
- Transcription, Genetic
- Transplantation, Heterologous
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Affiliation(s)
- ShengYu Ku
- Genitourinary Program, Roswell Park Cancer Institute, Buffalo, New York, United States of America
- Department of Cancer Prevention and Pathology, Roswell Park Cancer Institute, Buffalo, New York, United States of America
| | - Elena Lasorsa
- Genitourinary Program, Roswell Park Cancer Institute, Buffalo, New York, United States of America
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, New York, United States of America
| | - Remi Adelaiye
- Genitourinary Program, Roswell Park Cancer Institute, Buffalo, New York, United States of America
- Department of Cancer Prevention and Pathology, Roswell Park Cancer Institute, Buffalo, New York, United States of America
| | - Swathi Ramakrishnan
- Genitourinary Program, Roswell Park Cancer Institute, Buffalo, New York, United States of America
- Department of Cancer Prevention and Pathology, Roswell Park Cancer Institute, Buffalo, New York, United States of America
| | - Leigh Ellis
- Genitourinary Program, Roswell Park Cancer Institute, Buffalo, New York, United States of America
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Buffalo, New York, United States of America
- * E-mail: (LE); (RP)
| | - Roberto Pili
- Genitourinary Program, Roswell Park Cancer Institute, Buffalo, New York, United States of America
- Department of Medicine, Roswell Park Cancer Institute, Buffalo, New York, United States of America
- * E-mail: (LE); (RP)
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10
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White matter loss in a mouse model of periventricular leukomalacia is rescued by trophic factors. Brain Sci 2013; 3:1461-82. [PMID: 24961618 PMCID: PMC4061895 DOI: 10.3390/brainsci3041461] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2013] [Revised: 10/15/2013] [Accepted: 10/28/2013] [Indexed: 11/16/2022] Open
Abstract
Periventricular leukomalacia (PVL) is the most frequent cause of cerebral palsy and other intellectual disabilities, and currently there is no treatment. In PVL, glutamate excitotoxicity (GME) leads to abnormal oligodendrocytes (OLs), myelin deficiency, and ventriculomegaly. We have previously identified that the combination of transferrin and insulin growth factors (TSC1) promotes endogenous OL regeneration and remyelination in the postnatal and adult rodent brain. Here, we produced a periventricular white matter lesion with a single intracerebral injection of N-methyl-d-aspartate (NMDA). Comparing lesions produced by NMDA alone and those produced by NMDA + TSC1 we found that: NMDA affected survival and reduced migration of OL progenitors (OLPs). In contrast, mice injected with NMDA + TSC1 proliferated twice as much indicating that TSC1 supported regeneration of the OLP population after the insult. Olig2-mRNA expression showed 52% OLP survival in mice receiving a NMDA injection and increased to 78% when TSC1 + NMDA were injected simultaneously and ventricular size was reduced by TSC1. Furthermore, in striatal slices TSC1 reduced the inward currents induced by NMDA in medium-sized spiny neurons, demonstrating neuroprotection. Thus, white matter loss after excitotoxicity can be partially rescued as TSC1 conferred neuroprotection to preexisting OLP and regeneration via OLP proliferation. Furthermore, we showed that early TSC1 administration maximizes neuroprotection.
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11
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Danzer KM, McLean PJ. Drug targets from genetics: α-synuclein. CNS & NEUROLOGICAL DISORDERS-DRUG TARGETS 2013; 10:712-23. [PMID: 21838671 DOI: 10.2174/187152711797247867] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2010] [Revised: 07/22/2011] [Accepted: 07/24/2011] [Indexed: 02/08/2023]
Abstract
One of the critical issues in Parkinson disease (PD) research is the identity of the specific toxic, pathogenic moiety. In PD, mutations in α-synuclein (αsyn) or multiplication of the SNCA gene encoding αsyn, result in a phenotype of cellular inclusions, cell death, and brain dysfunction. While the historical point of view has been that the macroscopic aggregates containing αsyn are the toxic species, in the last several years evidence has emerged that suggests instead that smaller soluble species--likely oligomers containing misfolded αsyn--are actually the toxic moiety and that the fibrillar inclusions may even be a cellular detoxification pathway and less harmful. If soluble misfolded species of αsyn are the toxic moieties, then cellular mechanisms that degrade misfolded αsyn would be neuroprotective and a rational target for drug development. In this review we will discuss the fundamental mechanisms underlying αsyn toxicity including oligomer formation, oxidative stress, and degradation pathways and consider rational therapeutic strategies that may have the potential to prevent or halt αsyn induced pathogenesis in PD.
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Affiliation(s)
- Karin M Danzer
- MassGeneral Institute for Neurodegenerative Disease, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Charlestown, 02129, USA
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12
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Pore SK, Choudhary A, Rathore B, Ganguly A, Sujitha P, Kumar CG, Agawane SB, Kumar JM, Scaria V, Pillai B, Banerjee R. Hsp90-targeted miRNA-liposomal formulation for systemic antitumor effect. Biomaterials 2013; 34:6804-17. [PMID: 23773821 DOI: 10.1016/j.biomaterials.2013.05.054] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 05/08/2013] [Indexed: 12/20/2022]
Abstract
Chaperone protein Hsp90 maintains functional integrity and maturation of a large number of cellular proteins including transcription factors, kinases, etc. It is often over-expressed in cancer cells for simultaneous maintenance of many non-regulated and/or genetically mutated proteins. Small molecule-based regimens inhibiting over-expressing Hsp90 in cancer cells often plagued with improper targeting leading to non-specific toxicity. Recently using a glucocorticoid receptor (GR)-targeted cationic lipoplex, we observed cancer cell-specific GR-transactivation and transgene expression by utilizing an unprecedentedly compromised chaperone-activity of cancer cell-associated Hsp90. In normal cells, GR is expressed ubiquitously and is highly regulated and chaperoned by Hsp90. This does not allow cancer cell-alike GR-mediated transgene expression. As a novel anticancer strategy, we showed that compromising Hsp90 in cancer cells can be utilized to selectively deplete its own level by delivering a specially designed artificial miRNA-plasmid against Hsp90 (amiR-Hsp90). Practically, GR-mediated delivery of amiR-Hsp90 plasmid in tumor-bearing mice, depleted Hsp90, critically down-regulated levels of Akt, VEGFR2 and other Hsp90-client proteins but up-regulated wild-type p53 in tumor. These enforced apoptosis in angiogenic vessels and in tumor mass and significantly shrunk tumor-volume. The present study describes gene therapy strategy against Hsp90 using a new GR-targeted liposome-amiR-Hsp90 lipoplex formulation for treating cancer.
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Affiliation(s)
- Subrata Kumar Pore
- Division of Lipid Science & Technology, CSIR-Indian Institute of Chemical Technology, Hyderabad 500 007, India
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Cano LQ, Lavery DN, Bevan CL. Mini-review: Foldosome regulation of androgen receptor action in prostate cancer. Mol Cell Endocrinol 2013; 369:52-62. [PMID: 23395916 DOI: 10.1016/j.mce.2013.01.023] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 01/28/2013] [Accepted: 01/29/2013] [Indexed: 11/24/2022]
Abstract
Steroid hormone receptors play diverse roles in many aspects of human physiology including cell division, apoptosis and homeostasis, tissue differentiation, sexual development and response to stress. These ligand-activated transcription factors require the functional activity of numerous chaperone and chaperone-associated proteins, collectively termed the foldosome, at the crucial step of ligand recognition and binding. Since the initial isolation of foldosome components and pioneering research by Pratt, Toft and colleagues we understand much regarding cytosolic receptor function. The classical view, that the role of foldosome components is restricted to the cytosol, has been modified over recent years by research highlighting additional roles of chaperone proteins in nuclear translocation and target gene expression. Further, dysregulation of chaperone activity and expression has been implicated in various cancers, including breast and prostate cancer. Consequently, the foldosome provides an attractive therapeutic target in steroid hormone receptor-driven malignancies. This review summarises current knowledge of how the foldosome impacts upon androgen receptor signalling, which is the key therapeutic target on prostate cancer, and how foldosome components may be used as biomarkers or therapeutic targets in this disease.
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Affiliation(s)
- Laia Querol Cano
- Department of Surgery and Cancer, Imperial Centre for Translational and Experimental Medicine, Hammersmith Hospital Campus, Imperial College London, London, United Kingdom
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14
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Hsueh YS, Yen CC, Shih NY, Chiang NJ, Li CF, Chen LT. Autophagy is involved in endogenous and NVP-AUY922-induced KIT degradation in gastrointestinal stromal tumors. Autophagy 2012. [PMID: 23196876 PMCID: PMC3552885 DOI: 10.4161/auto.22802] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Gastrointestinal stromal tumor (GIST) is a prototype of mutant KIT oncogene-driven tumor. Prolonged tyrosine kinase inhibitor (TKI) treatment may result in a resistant phenotype through acquired secondary KIT mutation. Heat shock protein 90 (HSP90AA1) is a chaperone protein responsible for protein maturation and stability, and KIT is a known client protein of HSP90AA1. Inhibition of HSP90AA1 has been shown to destabilize KIT protein by enhancing its degradation via the proteasome-dependent pathway. In this study, we demonstrated that NVP-AUY922 (AUY922), a new class of HSP90AA1 inhibitor, is effective in inhibiting the growth of GIST cells expressing mutant KIT protein, the imatinib-sensitive GIST882 and imatinib-resistant GIST48 cells. The growth inhibition was accompanied with a sustained reduction of both total and phosphorylated KIT proteins and the induction of apoptosis in both cell lines. Surprisingly, AUY922-induced KIT reduction could be partially reversed by pharmacological inhibition of either autophagy or proteasome degradation pathway. The blockade of autophagy alone led to the accumulation of the KIT protein, highlighting the role of autophagy in endogenous KIT turnover. The involvement of autophagy in endogenous and AUY922-induced KIT protein turnover was further confirmed by the colocalization of KIT with MAP1LC3B-, acridine orange- or SQSTM1-labeled autophagosome, and by the accumulation of KIT in GIST cells by silencing either BECN1 or ATG5 to disrupt autophagosome activity. Therefore, the results not only highlight the potential application of AUY922 for the treatment of KIT-expressing GISTs, but also provide the first evidence for the involvement of autophagy in endogenous and HSP90AA1 inhibitor-induced KIT degradation.
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Affiliation(s)
- Yuan-Shuo Hsueh
- Institute of Clinical Pharmacy and Pharmaceutical Science, National Cheng Kung University, Tainan, Taiwan
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15
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Hong DS, Banerji U, Tavana B, George GC, Aaron J, Kurzrock R. Targeting the molecular chaperone heat shock protein 90 (HSP90): lessons learned and future directions. Cancer Treat Rev 2012. [PMID: 23199899 DOI: 10.1016/j.ctrv.2012.10.001] [Citation(s) in RCA: 190] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Due to the critical role of heat shock protein 90 (HSP90) in regulating the stability, activity and intracellular sorting of its client proteins involved in multiple oncogenic processes, HSP90 inhibitors are promising therapeutic agents for cancer treatment. In cancer cells, HSP90 client proteins play a major role in oncogenic signal transduction (i.e., mutant epidermal growth factor receptor), angiogenesis (i.e., vascular endothelial growth factor), anti-apoptosis (i.e., AKT), and metastasis (i.e., matrix metalloproteinase 2 and CD91), processes central to maintaining the cancer phenotype. Thus, HSP90 has emerged as a viable target for antitumor drug development, and several HSP90 inhibitors have transitioned to clinical trials. HSP90 inhibitors include geldanamycin and its derivatives (i.e., tanespimycin, alvespimycin, IPI-504), synthetic and small molecule inhibitors (i.e., AUY922, AT13387, STA9090, MPC3100), other inhibitors of HSP90 and its isoforms (i.e., shepherdin and 5'-N-ethylcarboxamideadenosine). With more than 200 "client" proteins, many of them meta-stable and oncogenic, HSP90 inhibition can affect an array of tumors. Here we review the molecular structure of HSP90, structural features of HSP90 inhibition, pharmacodynamic effects and tumor responses in clinical trials of HSP90 inhibitors. We also discuss lessons learned from completed clinical trials of HSP90 inhibitors, and future directions for these promising therapeutic agents.
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Affiliation(s)
- David S Hong
- Department of Investigational Cancer Therapeutics, Division of Cancer Medicine, The University of Texas M.D. Anderson Cancer Center, Houston, TX, USA.
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Centenera MM, Gillis JL, Hanson AR, Jindal S, Taylor RA, Risbridger GP, Sutherland PD, Scher HI, Raj GV, Knudsen KE, Yeadon T, Tilley WD, Butler LM. Evidence for efficacy of new Hsp90 inhibitors revealed by ex vivo culture of human prostate tumors. Clin Cancer Res 2012; 18:3562-70. [PMID: 22573351 DOI: 10.1158/1078-0432.ccr-12-0782] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Targeting Hsp90 has significant potential as a treatment for prostate cancer, but prototypical agents such as 17-allylamino-17 demethoxygeldanamycin (17-AAG) have been ineffective in clinical trials. Recently, a phase I study aimed at defining a biologically active dose reported the first response to an Hsp90 inhibitor in a patient with prostate cancer, which supports the development of new generation compounds for this disease. EXPERIMENTAL DESIGN The biological actions of two new synthetic Hsp90 inhibitors, NVP-AUY922 and NVP-HSP990, were evaluated in the prostate cancer cell lines PC-3, LNCaP, and VCaP and in an ex vivo culture model of human prostate cancer. RESULTS In cell lines, both NVP-AUY922 and NVP-HSP990 showed greater potency than 17-AAG with regard to modulation of Hsp90 client proteins, inhibition of proliferation, and induction of apoptotic cell death. In prostate tumors obtained from radical prostatectomy that were cultured ex vivo, treatment with 500 nmol/L of NVP-AUY922, NVP-HSP990, or 17-AAG caused equivalent target modulation, determined by the pharmacodynamic marker Hsp70, but only NVP-AUY922 and NVP-HSP990 showed antiproliferative and proapoptotic activity. CONCLUSIONS This study provides some of the first evidence that new generation Hsp90 inhibitors are capable of achieving biologic responses in human prostate tumors, with both NVP-AUY922 and NVP-HSP990 showing potent on-target efficacy. Importantly, the ex vivo culture technique has provided information on Hsp90 inhibitor action not previously observed in cell lines or animal models. This approach, therefore, has the potential to enable more rational selection of therapeutic agents and biomarkers of response for clinical trials.
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Affiliation(s)
- Margaret M Centenera
- Dame Roma Mitchell Cancer Research Laboratories and Adelaide Prostate Cancer Research Centre, University of Adelaide and Hanson Institute, Adelaide, Australia
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17
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Lodi A, Ronen SM. Magnetic resonance spectroscopy detectable metabolomic fingerprint of response to antineoplastic treatment. PLoS One 2011; 6:e26155. [PMID: 22022547 PMCID: PMC3192145 DOI: 10.1371/journal.pone.0026155] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Accepted: 09/21/2011] [Indexed: 01/10/2023] Open
Abstract
Targeted therapeutic approaches are increasingly being implemented in the clinic, but early detection of response frequently presents a challenge as many new therapies lead to inhibition of tumor growth rather than tumor shrinkage. Development of novel non-invasive methods to monitor response to treatment is therefore needed. Magnetic resonance spectroscopy (MRS) and magnetic resonance spectroscopic imaging are non-invasive imaging methods that can be employed to monitor metabolism, and previous studies indicate that these methods can be useful for monitoring the metabolic consequences of treatment that are associated with early drug target modulation. However, single-metabolite biomarkers are often not specific to a particular therapy. Here we used an unbiased 1H MRS-based metabolomics approach to investigate the overall metabolic consequences of treatment with the phosphoinositide 3-kinase inhibitor LY294002 and the heat shock protein 90 inhibitor 17AAG in prostate and breast cancer cell lines. LY294002 treatment resulted in decreased intracellular lactate, alanine fumarate, phosphocholine and glutathione. Following 17AAG treatment, decreased intracellular lactate, alanine, fumarate and glutamine were also observed but phosphocholine accumulated in every case. Furthermore, citrate, which is typically observed in normal prostate tissue but not in tumors, increased following 17AAG treatment in prostate cells. This approach is likely to provide further information about the complex interactions between signaling and metabolic pathways. It also highlights the potential of MRS-based metabolomics to identify metabolic signatures that can specifically inform on molecular drug action.
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Affiliation(s)
- Alessia Lodi
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, United States of America
| | - Sabrina M. Ronen
- Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, California, United States of America
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Yap TA, Zivi A, Omlin A, de Bono JS. The changing therapeutic landscape of castration-resistant prostate cancer. Nat Rev Clin Oncol 2011; 8:597-610. [PMID: 21826082 DOI: 10.1038/nrclinonc.2011.117] [Citation(s) in RCA: 118] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Castration-resistant prostate cancer (CRPC) has a poor prognosis and remains a significant therapeutic challenge. Before 2010, only docetaxel-based chemotherapy improved survival in patients with CRPC compared with mitoxantrone. Our improved understanding of the underlying biology of CRPC has heralded a new era in molecular anticancer drug development, with a myriad of novel anticancer drugs for CRPC entering the clinic. These include the novel taxane cabazitaxel, the vaccine sipuleucel-T, the CYP17 inhibitor abiraterone, the novel androgen-receptor antagonist MDV-3100 and the radioisotope alpharadin. With these developments, the management of patients with CRPC is changing. In this Review, we discuss these promising therapies along with other novel agents that are demonstrating early signs of activity in CRPC. We propose a treatment pathway for patients with CRPC and consider strategies to optimize the use of these agents, including the incorporation of predictive and intermediate end point biomarkers, such as circulating tumor cells.
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Affiliation(s)
- Timothy A Yap
- Drug Development Unit, The Royal Marsden NHS Foundation Trust and The Institute of Cancer Research, Downs Road, Sutton, Surrey SM2 5PT, UK
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19
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Modi S, Stopeck A, Linden H, Solit D, Chandarlapaty S, Rosen N, D'Andrea G, Dickler M, Moynahan ME, Sugarman S, Ma W, Patil S, Norton L, Hannah AL, Hudis C. HSP90 inhibition is effective in breast cancer: a phase II trial of tanespimycin (17-AAG) plus trastuzumab in patients with HER2-positive metastatic breast cancer progressing on trastuzumab. Clin Cancer Res 2011; 17:5132-9. [PMID: 21558407 DOI: 10.1158/1078-0432.ccr-11-0072] [Citation(s) in RCA: 320] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
PURPOSE HSP90 is a chaperone protein required for the stability of a variety of client proteins. 17-Demethoxygeldanamycin (17-AAG) is a natural product that binds to HSP90 and inhibits its activity, thereby inducing the degradation of these clients. In preclinical studies, HER2 is one of the most sensitive known client proteins of 17-AAG. On the basis of these data and activity in a phase I study, we conducted a phase II study of 17-AAG (tanespimycin) with trastuzumab in advanced trastuzumab-refractory HER2-positive breast cancer. EXPERIMENTAL DESIGN We enrolled patients with metastatic HER2(+) breast cancer whose disease had previously progressed on trastuzumab. All patients received weekly treatment with tanespimycin at 450 mg/m(2) intravenously and trastuzumab at a conventional dose. Therapy was continued until disease progression. The primary endpoint was response rate by Response Evaluation Criteria in Solid Tumors (RECIST) criteria. RESULTS Thirty-one patients were enrolled with a median age of 53 years and a median Karnofsky performance status (KPS) of 90%. The most common toxicities, largely grade 1, were diarrhea, fatigue, nausea, and headache. The overall response rate was 22%, the clinical benefit rate [complete response + partial response + stable disease] was 59%, the median progression-free survival was 6 months (95% CI: 4-9), and the median overall survival was 17 months (95% CI: 16-28). CONCLUSIONS This is the first phase II study to definitively show RECIST-defined responses for 17-AAG in solid tumors. Tanespimycin plus trastuzumab has significant anticancer activity in patients with HER2-positive, metastatic breast cancer previously progressing on trastuzumab. Further research exploring this therapeutic interaction and the activity of HSP90 inhibitors is clearly warranted.
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Affiliation(s)
- Shanu Modi
- Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA.
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In Vitro Activity of Geldanamycin Derivatives against Schistosoma japonicum and Brugia malayi. J Parasitol Res 2010; 2010:716498. [PMID: 21253549 PMCID: PMC3021863 DOI: 10.1155/2010/716498] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2010] [Revised: 10/22/2010] [Accepted: 11/23/2010] [Indexed: 12/24/2022] Open
Abstract
Geldanamycin (GA) is a benzoquinone-containing ansamycin that inhibits heat shock protein 90. GA derivatives are being evaluated as anti-neoplastic agents, but their utility against parasites whose heat shock proteins (Hsps) have homology with human Hsp90 is unknown. The activities of four synthetic GA derivatives were tested in vitro using adult Brugia malayi and Schistosoma japonicum. Two of the derivatives, 17-N-allyl-17-demethoxygeldanamycin (17-AAG) and 17-N-(2-dimethylaminoethylamino)-17-demethoxygeldanamycin (DMAG), are currently in human clinical trials as anticancer drugs. Using concentrations considered safe peak plasma concentrations for these two derivatives, all four derivatives were active against both parasites. The less toxic derivative 17-AAG was as effective as GA in killing S. japonicum, and both DMAG and 5′-bromogeldanoxazinone were more active than 17-AAG against B. malayi. This work supports continued evaluation of ansamycin derivatives as broad spectrum antiparasitic agents.
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Gong X, An Z, Wang Y, Guan L, Fang W, Strömblad S, Jiang Y, Zhang H. Kindlin-2 controls sensitivity of prostate cancer cells to cisplatin-induced cell death. Cancer Lett 2010; 299:54-62. [DOI: 10.1016/j.canlet.2010.08.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2010] [Revised: 08/05/2010] [Accepted: 08/09/2010] [Indexed: 01/06/2023]
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Pallavi R, Roy N, Nageshan RK, Talukdar P, Pavithra SR, Reddy R, Venketesh S, Kumar R, Gupta AK, Singh RK, Yadav SC, Tatu U. Heat shock protein 90 as a drug target against protozoan infections: biochemical characterization of HSP90 from Plasmodium falciparum and Trypanosoma evansi and evaluation of its inhibitor as a candidate drug. J Biol Chem 2010; 285:37964-75. [PMID: 20837488 DOI: 10.1074/jbc.m110.155317] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Using a pharmacological inhibitor of Hsp90 in cultured malarial parasite, we have previously implicated Plasmodium falciparum Hsp90 (PfHsp90) as a drug target against malaria. In this study, we have biochemically characterized PfHsp90 in terms of its ATPase activity and interaction with its inhibitor geldanamycin (GA) and evaluated its potential as a drug target in a preclinical mouse model of malaria. In addition, we have explored the potential of Hsp90 inhibitors as drugs for the treatment of Trypanosoma infection in animals. Our studies with full-length PfHsp90 showed it to have the highest ATPase activity of all known Hsp90s; its ATPase activity was 6 times higher than that of human Hsp90. Also, GA brought about more robust inhibition of PfHsp90 ATPase activity as compared with human Hsp90. Mass spectrometric analysis of PfHsp90 expressed in P. falciparum identified a site of acetylation that overlapped with Aha1 and p23 binding domain, suggesting its role in modulating Hsp90 multichaperone complex assembly. Indeed, treatment of P. falciparum cultures with a histone deacetylase inhibitor resulted in a partial dissociation of PfHsp90 complex. Furthermore, we found a well known, semisynthetic Hsp90 inhibitor, namely 17-(allylamino)-17-demethoxygeldanamycin, to be effective in attenuating parasite growth and prolonging survival in a mouse model of malaria. We also characterized GA binding to Hsp90 from another protozoan parasite, namely Trypanosoma evansi. We found 17-(allylamino)-17-demethoxygeldanamycin to potently inhibit T. evansi growth in a mouse model of trypanosomiasis. In all, our biochemical characterization, drug interaction, and animal studies supported Hsp90 as a drug target and its inhibitor as a potential drug against protozoan diseases.
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Affiliation(s)
- Rani Pallavi
- Department of Biochemistry, Indian Institute of Science, Bangalore, Karnataka 560012, India
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Abstract
Heat shock protein 90 (Hsp90) is a molecular chaperone involved in the trafficking of proteins in the cell. Under stressful conditions, Hsp90 stabilizes its client proteins and provides protection to the cell against cellular stressors such as in cancer cells. Disruption of Hsp90 leads to client protein degradation and often cell death. As Hsp90 has been found to be either overexpressed or constitutively more active in cancer cells, inhibitors of Hsp90 may have cancer cell selectivity. The N-terminal inhibitors, geldanamycin and radiciol, were the first two described inhibitors of Hsp90, but were not clinically useful. Subsequent analogues-17 allylamino-17demethoxygeldanamycin and 17 dimethylaminoethylamino-17-demethoxygeldanamycin-were found to be more clinically appropriate and have been studied in a number of clinical trials since 1999. In addition, to the N-terminal site of Hsp90, the C-terminal site appears to be another target for inhibition of Hsp90. More recently, inhibitors of the C terminus of Hsp90 have been developed and studied in vitro with promising results.
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Affiliation(s)
- Jeffrey M Holzbeierlein
- Department of Urology, University of Kansas Hospital, 3901 Rainbow Boulevard, Mail Stop 3016, Kansas, KS, 66160, USA.
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25
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Le HC, Lupu M, Kotedia K, Rosen N, Solit D, Koutcher JA. Proton MRS detects metabolic changes in hormone sensitive and resistant human prostate cancer models CWR22 and CWR22r. Magn Reson Med 2010; 62:1112-9. [PMID: 19780165 DOI: 10.1002/mrm.22137] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
17-Allylamino, 17-demethoxygeldanamycin (17-AAG), an effective inhibitor of the heat shock protein hsp90, preferentially inhibiting tumor hsp90 compared to hsp90 from normal cells, has shown promising results against several cancers, including hormone-resistant prostate cancer. Levels of several oncogenic proteins critical to tumor growth and progression, such as androgen receptor and HER2/neu, were reduced 4 h post 17-allylamino, 17-demethoxygeldanamycin treatment. Posttreatment metabolic changes have also been observed in several tumor cell lines. In this study, total choline distributions in hormone sensitive CWR22 and hormone resistant CWR22r prostate cancer xenograft tumors in mice were measured before and at 4 h and 48 h after a single-bolus 17-allylamino, 17-demethoxygeldanamycin treatment at 100 mg/kg, using proton MR spectroscopy. Our results show that tumor total choline levels declined 4 h after the treatment for CWR22 (P = 0.001) and 48 h post treatment for CWR22r (P = 0.003). Metabolic changes, in particular of total choline intensity detected by proton magnetic resonance spectroscopic imaging (MRSI), are consistent with the observed immunohistochemistry changes, tumor growth inhibition for CWR22r (P = 0.01 at 14 days post treatment), and a constant prostate specific antigen level versus increasing prostate specific antigen for control CWR22 (P = 0.01). Metabolic changes in total choline by proton MRSI can be used as an early biomarker of response for advanced-stage prostate cancer in targeted therapy such as 17-allylamino, 17-demethoxygeldanamycin.
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Affiliation(s)
- H Carl Le
- Department of Medical Physics, Memorial Sloan-Kettering Cancer Center, New York, New York 10021, USA.
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26
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Zhang T, Li Y, Yu Y, Zou P, Jiang Y, Sun D. Characterization of celastrol to inhibit hsp90 and cdc37 interaction. J Biol Chem 2009; 284:35381-9. [PMID: 19858214 PMCID: PMC2790967 DOI: 10.1074/jbc.m109.051532] [Citation(s) in RCA: 141] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2009] [Revised: 09/29/2009] [Indexed: 12/20/2022] Open
Abstract
The molecular chaperone heat shock protein 90 (Hsp90) is required for the stabilization and conformational maturation of various oncogenic proteins in cancer. The loading of protein kinases to Hsp90 is actively mediated by the cochaperone Cdc37. The crucial role of the Hsp90-Cdc37 complex has made it an exciting target for cancer treatment. In this study, we characterize Hsp90 and Cdc37 interaction and drug disruption using a reconstituted protein system. The GST pull-down assay and ELISA assay show that Cdc37 binds to ADP-bound/nucleotide-free Hsp90 but not ATP-bound Hsp90. Celastrol disrupts Hsp90-Cdc37 complex formation, whereas the classical Hsp90 inhibitors (e.g. geldanamycin) have no effect. Celastrol inhibits Hsp90 ATPase activity without blocking ATP binding. Proteolytic fingerprinting indicates celastrol binds to Hsp90 C-terminal domain to protect it from trypsin digestion. These data suggest that celastrol may represent a new class of Hsp90 inhibitor by modifying Hsp90 C terminus to allosterically regulate its chaperone activity and disrupt Hsp90-Cdc37 complex.
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Affiliation(s)
- Tao Zhang
- From the Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, Michigan 48109
| | - Yanyan Li
- From the Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, Michigan 48109
| | - Yanke Yu
- From the Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, Michigan 48109
| | - Peng Zou
- From the Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, Michigan 48109
| | - Yiqun Jiang
- From the Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, Michigan 48109
| | - Duxin Sun
- From the Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, Michigan 48109
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Putcha P, Danzer KM, Kranich LR, Scott A, Silinski M, Mabbett S, Hicks CD, Veal JM, Steed PM, Hyman BT, McLean PJ. Brain-permeable small-molecule inhibitors of Hsp90 prevent alpha-synuclein oligomer formation and rescue alpha-synuclein-induced toxicity. J Pharmacol Exp Ther 2009; 332:849-57. [PMID: 19934398 DOI: 10.1124/jpet.109.158436] [Citation(s) in RCA: 140] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Aggregation of alpha-synuclein (alphasyn) is a hallmark of sporadic and familial Parkinson's disease (PD) and dementia with Lewy bodies. Lewy bodies contain alphasyn and several heat shock proteins (Hsp), a family of molecular chaperones up-regulated by the cell under stress. We have previously shown that direct expression of Hsp70 and pharmacological up-regulation of Hsp70 by geldanamycin, an Hsp90 inhibitor, are protective against alphasyn-induced toxicity and prevent aggregation in culture. Here, we use a novel protein complementation assay to screen a series of small-molecule Hsp90 inhibitors for their ability to prevent alphasyn oligomerization and rescue toxicity. By use of this assay, we found that several compounds prevented alphasyn oligomerization as measured by decreased luciferase activity, led to a reduction in high-molecular-mass oligomeric alphasyn, and protected against alphasyn cytotoxicity. A lead compound, SNX-0723 (2-fluoro-6-[(3S)-tetrahydrofuran-3-ylamino]-4-(3,6,6-trimethyl-4-oxo-4,5,6,7-tetrahydro-1H-indol-1-yl)benzamide) was determined to have an EC(50) for inhibition of alphasyn oligomerization of approximately 48 nM and was able to rescue alphasyn-induced toxicity. In vivo assessment of SNX-0723 showed significant brain concentrations along with induction of brain Hsp70. With a low EC(50), brain permeability, and oral availability, these novel inhibitors represent an exciting new therapeutic strategy for PD.
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Affiliation(s)
- Preeti Putcha
- Department of Neurology, Massachusetts General Hospital, MassGeneral Institute for Neurodegenerative Disease, 114 16th Street, Charlestown, MA 02129, USA
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Li Y, Zhang T, Schwartz SJ, Sun D. New developments in Hsp90 inhibitors as anti-cancer therapeutics: mechanisms, clinical perspective and more potential. Drug Resist Updat 2009; 12:17-27. [PMID: 19179103 DOI: 10.1016/j.drup.2008.12.002] [Citation(s) in RCA: 128] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2008] [Revised: 11/26/2008] [Accepted: 12/04/2008] [Indexed: 12/20/2022]
Abstract
The molecular chaperone Hsp90 (heat shock protein 90) is a promising target in cancer therapy. Preclinical and clinical evaluations of a variety of Hsp90 inhibitors have shown anti-tumor effect as a single agent and in combination with chemotherapy. Current Hsp90 inhibitors are categorized into several classes based on distinct modes of inhibition, including (i) blockade of ATP binding, (ii) disruption of co-chaperone/Hsp90 interactions, (iii) antagonism of client/Hsp90 associations and (iv) interference with post-translational modifications of Hsp90. The different functions of Hsp90 isoforms and the isoform selectivity of drugs need further investigation. The correlation of cell surface Hsp90 with cancer metastasis and the emerging involvement of Hsp90 inhibition in cancer stem cells have become exciting areas that could be exploited. Therefore, the aim of this review is (1) to summarize the up-to-date knowledge of mechanistic studies and clinical prospect of currently available Hsp90 inhibitors, (2) to enhance our perspectives for designing and discovering novel Hsp90 inhibitors, and (3) to provide an insight into less-understood potential of Hsp90 inhibition in cancer therapy.
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Affiliation(s)
- Yanyan Li
- Department of Pharmaceutical Sciences, University of Michigan, MI 48109, USA
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Abstract
Heat shock protein 90 (HSP90) is a ubiquitously expressed chaperone that is involved in the posttranslational folding and stability of proteins. Inhibition at the NH(2)-terminal ATP-binding site leads to the degradation of client proteins by the ubiquitin proteasome pathway. Inhibition of HSP90 leads to the degradation of known oncogenes, such as ERB-B2, BRAF, and BCR-ABL, leading to the combinatorial blockade of multiple signal transduction pathways, such as the RAS-RAF-mitogen-activated protein/extracellular signal-regulated kinase kinase-extracellular signal-regulated kinase and phosphatidylinositol 3-kinase pathways. Multiple structurally diverse HSP90 inhibitors are undergoing early clinical evaluation. The clinical focus of these drugs should be solid tumors, such as breast, prostate, and lung cancers, along with malignant melanoma, in addition to hematologic malignancies, such as chronic myeloid leukemia and multiple myeloma. HSP90 inhibitors can be used as single agents or in combination with other targeted treatments or conventional forms of treatment such as chemotherapy and radiotherapy. Clinical trials evaluating efficacy of these agents should include innovative designs to capture cytostasis evidenced by clinical nonprogression and enrichment of patient populations by molecular characterization. The results of clinical trials evaluating the efficacy of drugs targeting this exciting target are awaited.
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Affiliation(s)
- Udai Banerji
- Section of Medicine, The Royal Marsden Hospital/The Institute of Cancer Research, Surrey, United Kingdom.
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Tenenbaum JD, Walker MG, Utz PJ, Butte AJ. Expression-based Pathway Signature Analysis (EPSA): mining publicly available microarray data for insight into human disease. BMC Med Genomics 2008; 1:51. [PMID: 18937865 PMCID: PMC2588448 DOI: 10.1186/1755-8794-1-51] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2008] [Accepted: 10/20/2008] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Publicly available data repositories facilitate the sharing of an ever-increasing amount of microarray data. However, these datasets remain highly underutilized. Reutilizing the data could offer insights into questions and diseases entirely distinct from those considered in the original experimental design. METHODS We first analyzed microarray datasets derived from known perturbations of specific pathways using the samr package in R to identify specific patterns of change in gene expression. We refer to these pattern of gene expression alteration as a "pathway signatures." We then used Spearman's rank correlation coefficient, a non-parametric measure of correlation, to determine similarities between pathway signatures and disease profiles, and permutation analysis to evaluate false discovery rate. This enabled detection of statistically significant similarity between these pathway signatures and corresponding changes observed in human disease. Finally, we evaluated pathway activation, as indicated by correlation with the pathway signature, as a risk factor for poor prognosis using multiple unrelated, publicly available datasets. RESULTS We have developed a novel method, Expression-based Pathway Signature Analysis (EPSA). We demonstrate that ESPA is a rigorous computational approach for statistically evaluating the degree of similarity between highly disparate sources of microarray expression data. We also show how EPSA can be used in a number of cases to stratify patients with differential disease prognosis. EPSA can be applied to many different types of datasets in spite of different platforms, different experimental designs, and different species. Applying this method can yield new insights into human disease progression. CONCLUSION EPSA enables the use of publicly available data for an entirely new, translational purpose to enable the identification of potential pathways of dysregulation in human disease, as well as potential leads for therapeutic molecular targets.
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Affiliation(s)
- Jessica D Tenenbaum
- Stanford Medical Informatics, 251 Campus Drive MSOB x215, Stanford, CA 94305, USA.
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McCollum AK, TenEyck CJ, Stensgard B, Morlan BW, Ballman KV, Jenkins RB, Toft DO, Erlichman C. P-Glycoprotein-mediated resistance to Hsp90-directed therapy is eclipsed by the heat shock response. Cancer Res 2008; 68:7419-27. [PMID: 18794130 DOI: 10.1158/0008-5472.can-07-5175] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Despite studies that show the antitumor activity of Hsp90 inhibitors, such as geldanamycin (GA) and its derivative 17-allylamino-demethoxygeldanamycin (17-AAG), recent reports indicate that these inhibitors lack significant single-agent clinical activity. Resistance to Hsp90 inhibitors has been previously linked to expression of P-glycoprotein (P-gp) and the multidrug resistant (MDR) phenotype. However, the stress response induced by GA treatment can also cause resistance to Hsp90-targeted therapy. Therefore, we chose to further investigate the relative importance of P-gp and the stress response in 17-AAG resistance. Colony-forming assays revealed that high expression of P-gp could increase the 17-AAG IC(50) 6-fold in cells transfected with P-gp compared with parent cells. A549 cells selected for resistance to GA overexpressed P-gp, but verapamil did not reverse the resistance. These cells also overexpressed Hsp27, and Hsp70 was induced with 17-AAG treatment. When the GA and 17-AAG resistant cells were transfected with Hsp27 and/or Hsp70 small interfering RNA (siRNA), the 17-AAG IC(50) decreased 10-fold compared with control transfected cells. Transfection with siRNA directed against Hsp27, Hsp70, or Hsp27 and Hsp70 also increased sensitivity to EC78, a purine scaffold-based Hsp90 inhibitor that is not a P-gp substrate. We conclude that P-gp may contribute, in part, to resistance to 17-AAG, but induction of stress response proteins, such as Hsp27 and Hsp70, by Hsp90-targeted therapy plays a larger role. Taken together, our results indicate that targeting of Hsp27 and Hsp70 should be exploited to increase the clinical efficacy of Hsp90-directed therapy.
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Affiliation(s)
- Andrea K McCollum
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA
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Development and validation of a rapid and sensitive high-performance liquid chromatography-mass spectroscopy assay for determination of 17-(allylamino)-17-demethoxygeldanamycin and 17-(amino)-17-demethoxygeldanamycin in human plasma. J Chromatogr B Analyt Technol Biomed Life Sci 2008; 871:15-21. [PMID: 18635408 DOI: 10.1016/j.jchromb.2008.06.029] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2008] [Revised: 06/09/2008] [Accepted: 06/13/2008] [Indexed: 11/23/2022]
Abstract
A sensitive method was developed and validated for the measurement of 17-(allylamino)-17-demethoxygeldanamycin (17AAG) and its active metabolite 17-amino-17-demethoxygeldanamycin (17AG) in human plasma using 17-(dimethylaminoethylamino)-17-demethoxygeldanamycin (17DMAG) as an internal standard. After the addition of internal standard, 200 microL of plasma was extracted using ice cold acetonitrile followed by analysis on a Thermo Finnigan triple-quadruple mass spectrometer coupled to an Agilent 1100 HPLC system. Chromatography was carried out on a 50 mm x 2.1 mm Agilent Zorbax SB-phenyl 5 microm column coupled to a 3mm Varian metaguard diphenyl pre-column using glacial acetic acid 0.1% and a gradient of acetonitrile and water at a flow rate of 500 microL/min. Atmospheric pressure chemical ionization and detection of 17AAG, 17AG and 17DMAG were accomplished using selected reaction monitoring of m/z 584.3>541.3, 544.2>501.2, and 615.3>572.3, respectively in negative ion mode. Retention times for 17AAG, 17AG, and 17DMAG were 4.1, 3.5, and 2.9 min, respectively, with a total run time of 7 min. The assay was linear over the range 0.5-3000 ng/mL for 17AAG and 17AG. Replicate sample analysis indicated within- and between-run accuracy and precision within 15%. The recovery of 17AAG and 17AG from 200 microL of plasma containing 1, 25, 300, and 2500 ng/mL was 93% or greater. This high-performance liquid chromatographic tandem mass spectroscopy (HPLC/MS/MS) method is superior to previous methods. It is the first analytical method reported to date for the quantitation of both 17AAG and its metabolite 17AG and can reliably quantitate concentrations of both compounds as low as 0.5 ng/mL.
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Lang SA, Moser C, Gaumann A, Klein D, Glockzin G, Popp FC, Dahlke MH, Piso P, Schlitt HJ, Geissler EK, Stoeltzing O. Targeting heat shock protein 90 in pancreatic cancer impairs insulin-like growth factor-I receptor signaling, disrupts an interleukin-6/signal-transducer and activator of transcription 3/hypoxia-inducible factor-1alpha autocrine loop, and reduces orthotopic tumor growth. Clin Cancer Res 2008; 13:6459-68. [PMID: 17975158 DOI: 10.1158/1078-0432.ccr-07-1104] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Inhibitors of heat-shock protein 90 (Hsp90) may interfere with oncogenic signaling pathways, including Erk, Akt, and hypoxia-inducible factor-1alpha (HIF-1alpha). Because insulin-like growth factor-I receptor (IGF-IR) and signal transducer and activator of transcription 3 (STAT3) signaling pathways are implicated in the progression of pancreatic cancer, we hypothesized that blocking Hsp90 with geldanamycin derivates [17-allylamino-geldanamycin (17-AAG), 17-(dimethylaminoethylamino)-17-demethoxygeldanamycin (17-DMAG)] would impair IGF-I- and interleukin-6-mediated signaling and thus reduce pancreatic tumor growth and angiogenesis in vivo. EXPERIMENTAL DESIGN Human pancreatic cancer cells (HPAF-II, L3.6pl) were used for experiments. Changes in signaling pathway activation upon Hsp90 blockade were investigated by Western blotting. Effects of Hsp90 inhibition (17-AAG) on vascular endothelial growth factor were determined by ELISA and real-time PCR. Effects of 17-DMAG (25 mg/kg; thrice a week; i.p.) on tumor growth and vascularization were investigated in a s.c. xenograft model and in an orthotopic model of pancreatic cancer. RESULTS 17-AAG inhibited IGF-IR signaling by down-regulating IGF-IRbeta and directly impairing IGF-IR phosphorylation. Hypoxia- and IL-6-mediated activation of HIF-1alpha or STAT3/STAT5 were substantially inhibited by 17-AAG. Moreover, a novel IL-6/STAT3/HIF-1alpha autocrine loop was effectively disrupted by Hsp90 blockade. In vivo, 17-DMAG significantly reduced s.c. tumor growth and diminished STAT3 phosphorylation and IGF-IRbeta expression in tumor tissues. In an orthotopic model, pancreatic tumor growth and vascularization were both significantly reduced upon Hsp90 inhibition, as reflected by final tumor weights and CD31 staining, respectively. CONCLUSIONS Blocking Hsp90 disrupts IGF-I and IL-6-induced proangiogenic signaling cascades by targeting IGF-IR and STAT3 in pancreatic cancer, leading to significant growth-inhibitory effects. Therefore, we suggest that Hsp90 inhibitors could prove to be valuable in the treatment of pancreatic cancer.
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Affiliation(s)
- Sven A Lang
- Department of Surgery, University of Regensburg Medical Center, Regensburg, Germany
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Apoptotic pathways in tumor progression and therapy. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2008; 615:47-79. [PMID: 18437891 DOI: 10.1007/978-1-4020-6554-5_4] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Apoptosis is a cell suicide program that plays a critical role in development and tissue homeostasis. The ability of cancer cells to evade this programmed cell death (PCD) is a major characteristic that enables their uncontrolled growth. The efficiency of chemotherapy in killing such cells depends on the successful induction of apoptosis, since defects in apoptosis signaling are a major cause of drug resistance. Over the past decades, much progress has been made in our understanding of apoptotic signaling pathways and their dysregulation in cancer progression and therapy. These advances have provided new molecular targets for proapoptotic cancer therapies that have recently been used in drug development. While most of those therapies are still at the preclinical stage, some of them have shown much promise in the clinic. Here, we review our current knowledge of apoptosis regulation in cancer progression and therapy, as well as the new molecular targeted molecules that are being developed to reinstate cancer cell death.
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Abstract
Over the past 5 years, the Raf kinase family has emerged as a promising target for protein-directed cancer therapy development. The goal of this review is to first provide a concise summary of the data validating Raf proteins as high-interest therapeutic targets. The authors then outline the mode of action of Raf kinases, emphasizing how Raf activities and protein interactions suggest specific approaches to inhibiting Raf. The authors then summarize the set of drugs, antisense reagents and antibodies available or in development for therapeutically targeting Raf or Raf-related proteins, as well as existing strategies combining these and other therapeutic agents. Finally, the authors discuss recent results from systems biology analyses that have the potential to increasingly guide the intelligent selection of combination therapies involving Raf-targeting agents and other therapeutics.
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Moser C, Lang SA, Kainz S, Gaumann A, Fichtner-Feigl S, Koehl GE, Schlitt HJ, Geissler EK, Stoeltzing O. Blocking heat shock protein-90 inhibits the invasive properties and hepatic growth of human colon cancer cells and improves the efficacy of oxaliplatin in p53-deficient colon cancer tumors in vivo. Mol Cancer Ther 2007; 6:2868-78. [DOI: 10.1158/1535-7163.mct-07-0410] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Tsutsumi S, Scroggins B, Koga F, Lee MJ, Trepel J, Felts S, Carreras C, Neckers L. A small molecule cell-impermeant Hsp90 antagonist inhibits tumor cell motility and invasion. Oncogene 2007; 27:2478-87. [PMID: 17968312 DOI: 10.1038/sj.onc.1210897] [Citation(s) in RCA: 131] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Heat shock protein 90 (Hsp90) is a molecular chaperone that maintains function of numerous intracellular signaling nodes utilized by cancer cells for proliferation and survival. Hsp90 is also detected on the plasma membrane of tumor cells and its expression has been suggested to correlate with metastatic potential. Given the abundance and diverse functions of the intracellular pool of this protein, the precise contribution of cell surface Hsp90 to cell motility and tumor metastasis remains to be determined. In this study we utilized the small molecule DMAG-N-oxide, a novel cell-impermeable Hsp90 inhibitor, to specifically examine the role of cell surface Hsp90 in cell motility. We observed that, while not affecting intracellular Hsp90 function, DMAG-N-oxide significantly retarded tumor cell migration and integrin/extracellular matrix-dependent cytoskeletal reorganization. Concomitant with these findings, targeting cell surface Hsp90 significantly inhibited tumor cell motility and invasion in vitro, and had a dramatic impact on melanoma cell lung colonization in vivo. These data indicate that cell surface Hsp90 plays an important role in modulating cancer cell migration that is independent of the function of the intracellular Hsp90 pool, and that small molecule inhibitors of surface Hsp90 may provide a new approach to targeting the metastatic phenotype.
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Affiliation(s)
- S Tsutsumi
- Urologic Oncology Branch, National Cancer Institute, Bethesda, MD 20892-1107, USA
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Lang SA, Klein D, Moser C, Gaumann A, Glockzin G, Dahlke MH, Dietmaier W, Bolder U, Schlitt HJ, Geissler EK, Stoeltzing O. Inhibition of heat shock protein 90 impairs epidermal growth factor-mediated signaling in gastric cancer cells and reduces tumor growth and vascularization in vivo. Mol Cancer Ther 2007; 6:1123-32. [PMID: 17363505 DOI: 10.1158/1535-7163.mct-06-0628] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Oncogenic signaling through activation of epidermal growth factor receptor (EGFR), HER-2, and hypoxia inducible-factor-1alpha (HIF-1alpha) has been implicated in gastric cancer growth and angiogenesis through up-regulation of vascular endothelial growth factor (VEGF). Recently, heat shock protein 90 (Hsp90) has been identified as a critical regulator of oncogenic protein stability, including EGFR, HER-2, and HIF-1alpha. We hypothesized that inhibition of Hsp90 impairs EGF- and hypoxia-mediated angiogenic signaling in gastric cancer cells and consequently inhibits angiogenesis and tumor growth. In vitro, the geldanamycin derivate 17-allylamino-17-demethoxygeldanamycin (17-AAG) led to marked reduction in constitutive and inducible activation of extracellular signal-regulated kinase 1/2, Akt, and signal transducer and activator of transcription 3 and decreased nuclear HIF-1alpha protein. In addition, EGFR and HER-2 were down-regulated after Hsp90 inhibition. With respect to regulation of angiogenic molecules, 17-AAG significantly reduced EGF-mediated VEGF secretion. Phosphorylation of focal adhesion kinase and paxillin were both abrogated by 17-AAG, which resulted in significant impairment of cancer cell motility. Interestingly, cytotoxic effects of 17-AAG in vitro were higher on cancer cells and gastric fibroblasts than on pericytes. In vivo, the water-soluble compound 17-dimethylaminoethylamino-17-demethoxygeldanamycin (17-DMAG; 25 mg/kg, thrice per week) significantly reduced s.c. xenografted tumor growth. By immunohistochemistry, 17-DMAG significantly reduced vessel area and numbers of proliferating tumor cells in sections. Furthermore, similar significant growth-inhibitory effects of 17-DMAG were achieved when administered as low-dose therapy (5 mg/kg, thrice per week). In conclusion, blocking Hsp90 disrupts multiple proangiogenic signaling pathways in gastric cancer cells and inhibits xenografted tumor growth in vivo. Hence, gastric cancer harbors attractive molecular targets for therapy with Hsp90 inhibitors, which could lead to improved efficacy of antineoplastic therapy regimens.
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MESH Headings
- Angiogenesis Inhibitors/therapeutic use
- Animals
- Benzoquinones/pharmacology
- Blood Vessels/drug effects
- Blood Vessels/growth & development
- Blood Vessels/metabolism
- Cell Hypoxia/drug effects
- Cell Line, Tumor/drug effects
- Cell Movement/drug effects
- Cell Proliferation/drug effects
- Cyclic AMP Response Element-Binding Protein/metabolism
- Enzyme-Linked Immunosorbent Assay
- Epidermal Growth Factor/metabolism
- ErbB Receptors/metabolism
- Extracellular Signal-Regulated MAP Kinases/metabolism
- Fibroblasts/drug effects
- Fibroblasts/metabolism
- HSP90 Heat-Shock Proteins/antagonists & inhibitors
- HSP90 Heat-Shock Proteins/metabolism
- Humans
- Hypoxia-Inducible Factor 1, alpha Subunit/metabolism
- Lactams, Macrocyclic/pharmacology
- Male
- Mice
- Mice, Inbred BALB C
- Mitogen-Activated Protein Kinases/metabolism
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/metabolism
- Neovascularization, Pathologic/drug therapy
- Pericytes/drug effects
- Pericytes/metabolism
- Proto-Oncogene Proteins c-akt
- Receptor, ErbB-2/metabolism
- Signal Transduction/physiology
- Stomach Neoplasms/blood supply
- Stomach Neoplasms/metabolism
- Vascular Endothelial Growth Factor A/metabolism
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Affiliation(s)
- Sven A Lang
- Departments of Surgery and Surgical Oncology, University of Regensburg, Franz-Josef-Strauss Allee 11, 93042 Regensburg, Germany
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Oh SH, Woo JK, Yazici YD, Myers JN, Kim WY, Jin Q, Hong SS, Park HJ, Suh YG, Kim KW, Hong WK, Lee HY. Structural basis for depletion of heat shock protein 90 client proteins by deguelin. J Natl Cancer Inst 2007; 99:949-61. [PMID: 17565155 DOI: 10.1093/jnci/djm007] [Citation(s) in RCA: 113] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND The molecular chaperone heat shock protein 90 (Hsp90) participates in preserving the expression and activity of various oncoproteins, including hypoxia-inducible factor 1alpha (HIF-1alpha) and Akt. Deguelin is a rotenoid with antitumor activities. We investigated whether the antitumor activities of deguelin involve the functional inhibition of Hsp90. METHOD Human xenograft tumors were generated in mice from H1299 (n = 6 per group) and A549 (n = 4 per group) non-small-cell lung cancer cells, UMSCC38 (n = 5 per group) head and neck cancer cells, MKN45 (n = 5 per group) stomach cancer cells, and PC-3 (n = 3 per group) prostate cancer cells. Tumor-bearing mice were treated with deguelin at 4 or 8 mg/kg or with vehicle (as a control) twice a day by oral gavage for 15-28 days. Protein expression was assessed by western blot analysis. Akt and Hsp90 were assessed by use of adenoviral vectors expressing constitutively active Akt or Hsp90. Binding of deguelin to Hsp90 was examined by docking analysis and by competition binding experiments with ATP-Sepharose beads. The proteasome inhibitor MG132 was used to investigate deguelin's effect on the induction of ubiquitin-mediated proteasomal degradation of HIF-1alpha. All statistical tests were two-sided. RESULTS Deguelin bound to the ATP-binding pocket of Hsp90 and disrupted Hsp90 function, leading to ubiquitin-mediated degradation of HIF-1alpha. Administration of deguelin to xenograft-bearing mice statistically significantly decreased tumor growth by inducing apoptosis and decreasing the expression of Hsp90 client proteins, without detectable toxic effects. For example, at 15 days after the start of deguelin treatment, the volume of untreated control H1299 xenograft tumors was 798 mm3 and that of xenograft tumors treated with deguelin at 4 mg/kg was 115.9 mm3 (difference = 682.1 mm3, 95% confidence interval = 480.4 to 883.9 mm3; P<.001). CONCLUSIONS The antitumor activities of deguelin appear to involve its binding to the ATP-binding pocket of Hsp90, which suppresses Hsp90 function.
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Affiliation(s)
- Seung Hyun Oh
- Department of Thoracic/Head and Neck Medical Oncology, The University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA
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Abstract
Irrespective of the morphological features of end-stage cell death (that may be apoptotic, necrotic, autophagic, or mitotic), mitochondrial membrane permeabilization (MMP) is frequently the decisive event that delimits the frontier between survival and death. Thus mitochondrial membranes constitute the battleground on which opposing signals combat to seal the cell's fate. Local players that determine the propensity to MMP include the pro- and antiapoptotic members of the Bcl-2 family, proteins from the mitochondrialpermeability transition pore complex, as well as a plethora of interacting partners including mitochondrial lipids. Intermediate metabolites, redox processes, sphingolipids, ion gradients, transcription factors, as well as kinases and phosphatases link lethal and vital signals emanating from distinct subcellular compartments to mitochondria. Thus mitochondria integrate a variety of proapoptotic signals. Once MMP has been induced, it causes the release of catabolic hydrolases and activators of such enzymes (including those of caspases) from mitochondria. These catabolic enzymes as well as the cessation of the bioenergetic and redox functions of mitochondria finally lead to cell death, meaning that mitochondria coordinate the late stage of cellular demise. Pathological cell death induced by ischemia/reperfusion, intoxication with xenobiotics, neurodegenerative diseases, or viral infection also relies on MMP as a critical event. The inhibition of MMP constitutes an important strategy for the pharmaceutical prevention of unwarranted cell death. Conversely, induction of MMP in tumor cells constitutes the goal of anticancer chemotherapy.
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Affiliation(s)
- Guido Kroemer
- Institut Gustave Roussy, Institut National de la Santé et de la Recherche Médicale Unit "Apoptosis, Cancer and Immunity," Université de Paris-Sud XI, Villejuif, France
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Lattouf JB, Srinivasan R, Pinto PA, Linehan WM, Neckers L. Mechanisms of disease: the role of heat-shock protein 90 in genitourinary malignancy. ACTA ACUST UNITED AC 2007; 3:590-601. [PMID: 17088927 DOI: 10.1038/ncpuro0604] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2006] [Accepted: 08/14/2006] [Indexed: 12/28/2022]
Abstract
Insight into the molecular biology of cancer has allowed the development of novel therapeutic strategies that target specific oncogenic pathways. Molecular therapeutic strategies are now part of the armamentarium available against urologic malignancy. Among the many targets of interest in urologic cancer, heat-shock protein 90 (HSP90) shows great promise. This molecule has a major role in prostate as well as in renal malignancy. In contrast to other targets, where cancer might escape inhibition via alternative pathways, HSP90 operates at multiple checkpoints in a cancer cell. Its inhibition could, therefore, prove more difficult for neoplastic cells to overcome. Inhibitors of HSP90, such as geldanamycin and its derivatives (17-allylamino-17-demethoxygeldanamycin and 17-dimethylaminoethylamino-17-demethoxygeldanamycin, known as 17AAG and 17DMAG, respectively) are available and have shown activity both in vivo and in vitro. 17AAG is currently being tested for efficacy in humans after having completed phase I trials, while 17DMAG is still in phase I evaluation. Phase II trials of HSP90 inhibitors in urologic malignancy are being conducted in kidney and advanced prostate cancer. Beyond monotherapy, HSP90 inhibitors might also prove to be beneficial in combination therapy with other chemotherapeutic agents in advanced disease. Studies being conducted in prostate cancer will hopefully help to define this potential application better.
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Affiliation(s)
- Jean-Baptiste Lattouf
- Urologic Oncology Branch, National Cancer Institute, Room 1-5942, Building 10 CRC, 9000 Rockville Pike, Bethesda, MD 20892, USA
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Bachetti T, Bocca P, Borghini S, Matera I, Prigione I, Ravazzolo R, Ceccherini I. Geldanamycin promotes nuclear localisation and clearance of PHOX2B misfolded proteins containing polyalanine expansions. Int J Biochem Cell Biol 2007; 39:327-39. [PMID: 17045833 DOI: 10.1016/j.biocel.2006.08.014] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2006] [Revised: 08/17/2006] [Accepted: 08/18/2006] [Indexed: 12/19/2022]
Abstract
Polyalanine expansions in the PHOX2B gene have been detected in the vast majority of patients affected with congenital central hypoventilation syndrome, a neurocristopathy characterized by absence of adequate control of breathing, especially during sleep, with decreased sensitivity to hypoxia and hypercapnia. The correlation between length of the alanine expanded tracts and severity of congenital central hypoventilation syndrome respiratory phenotype has been confirmed by length-dependent cytoplasmic PHOX2B retention with formation of aggregates. To deepen into the molecular mechanisms mediating the effects of PHOX2B polyalanine expansions, we have set up experiments aimed at assessing the fate of cells characterized by PHOX2B polyalanine aggregates. In particular, we have observed that activation of the heat shock response by the drug geldanamycin is efficient both in preventing formation and in inducing clearance of PHOX2B pre-formed polyalanine aggregates in COS-7 cells expressing PHOX2B-GFP fused proteins, and ultimately also in rescuing the PHOX2B ability to transactivate the Dopamine-beta-Hydroxilase promoter. In addition, we have demonstrated elimination of PHOX2B mutant proteins by the proteasome and autophagy, two cellular mechanisms already been involved in the clearance of proteins containing expanded polyglutamine and polyalanine tracts. Moreover, our data suggest that geldanamycin effects on PHOX2B aggregates may be also mediated by the proteasome pathway. Finally, analysis of cellular toxicity due to polyalanine aggregates has confirmed the occurrence of cell apoptosis consequent to expression of PHOX2B carrying the longest expanded alanine tract and shown that geldanamycin can delay cell progression toward the most advanced apoptotic stages.
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Affiliation(s)
- Tiziana Bachetti
- Laboratorio di Genetica Molecolare, Istituto Giannina Gaslini, Largo G. Gaslini 5, 16148 Genova, Italy.
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Abstract
Our understanding of growth factors and growth-factor receptors, signal transduction pathways, cellular survival pathways, angiogenesis, and their potential roles in prostate-cancer tumorigenesis remains a work in progress. Novel agents targeting these key mechanisms are showing promise in clinical trials. Many more agents, including those not discussed in this article, such as radio-pharmaceuticals, bisphosphonates, nutriceuticals, immunotherapy, and newer generation chemotherapy, are also showing promise as emerging treatments for prostate cancer. It is important to recognize when designing clinical trials of novel agents that traditional endpoints of disease response may not be applicable in measuring success of biologic compounds. Especially in a disease where tumor marker levels are critical for both patient and physician, additional biomarkers are necessary to better assess response. Halting drug development due to lack of response in serum PSA may lead to an unnecessary demise of an active agent.As expected, the combination of biologic agent with cytotoxic chemotherapy has a higher traditional response rate compared with biologic agent alone. The challenge of combination trials is to determine if the combination of agents will produce a higher traditional response rate compared with chemotherapy alone. For several of the agents discussed, the clinical benefit derived from a combination of biologic agent and cytotoxic chemotherapy may not justify additional drug toxicity. Efficient trial design, appropriate selection of correlative markers,and close toxicity monitoring will help improve our ability to identify promising novel agents.
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Affiliation(s)
- Elisabeth I Heath
- Barbara Ann Karmanos Cancer Institute, 4100 John R, 4 HWCRC, Detroit, MI 48201, USA.
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Waza M, Adachi H, Katsuno M, Minamiyama M, Tanaka F, Doyu M, Sobue G. Modulation of Hsp90 function in neurodegenerative disorders: a molecular-targeted therapy against disease-causing protein. J Mol Med (Berl) 2006; 84:635-46. [PMID: 16741751 DOI: 10.1007/s00109-006-0066-0] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2006] [Accepted: 03/14/2006] [Indexed: 10/24/2022]
Abstract
Abnormal accumulation of disease-causing protein is a commonly observed characteristic in chronic neurodegenerative disorders such as Alzheimer's disease, Parkinson's disease, and polyglutamine (polyQ) diseases. A therapeutic approach that could selectively eliminate would be a promising remedy for neurodegenerative disorders. Spinal and bulbar muscular atrophy (SBMA), one of the polyQ diseases, is a late-onset motor neuron disease characterized by proximal muscle atrophy, weakness, contraction fasciculations, and bulbar involvement. The pathogenic gene product is polyQ-expanded androgen receptor (AR), which belongs to the heat shock protein (Hsp) 90 client protein family. 17-Allylamino-17-demethoxygeldanamycin (17-AAG), a novel Hsp90 inhibitor, is a new derivative of geldanamycin that shares its important biological activities but shows less toxicity. 17-AAG is now in phase II clinical trials as a potential anti-cancer agent because of its ability to selectively degrade several oncoproteins. We have recently demonstrated the efficacy and safety of 17-AAG in a mouse model of SBMA. The administration of 17-AAG significantly ameliorated polyQ-mediated motor neuron degeneration by reducing the total amount of mutant AR. 17-AAG accomplished the preferential reduction of mutant AR mainly through Hsp90 chaperone complex formation and subsequent proteasome-dependent degradation. 17-AAG induced Hsp70 and Hsp40 in vivo as previously reported; however, its ability to induce HSPs was limited, suggesting that the HSP induction might support the degradation of mutant protein. The ability of 17-AAG to preferentially degrade mutant protein would be directly applicable to SBMA and other neurodegenerative diseases in which the disease-causing proteins also belong to the Hsp90 client protein family. Our proposed therapeutic approach, modulation of Hsp90 function by 17-AAG treatment, has emerged as a candidate for molecular-targeted therapies for neurodegenerative diseases. This review will consider our research findings and discuss the possibility of a clinical application of 17-AAG to SBMA and other neurodegenerative diseases.
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Affiliation(s)
- Masahiro Waza
- Department of Neurology, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, 466-8550 Nagoya, Japan
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