1
|
Sverchinsky DV, Alhasan BA, Mikeladze MA, Lazarev VF, Kuznetcova LS, Morshneva AV, Nikotina AD, Ziewanah A, Koludarova LV, Starkova TY, Margulis BA, Guzhova IV. Autocrine regulation of tumor cell repopulation by Hsp70-HMGB1 alarmin complex. J Exp Clin Cancer Res 2023; 42:279. [PMID: 37880798 PMCID: PMC10598926 DOI: 10.1186/s13046-023-02857-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Accepted: 10/08/2023] [Indexed: 10/27/2023] Open
Abstract
BACKGROUND Cancer recurrence is regulated by a variety of factors, among which is the material of dying tumor cells; it is suggested that remaining after anti-cancer therapy tumor cells receive a signal from proteins called damage-associated molecular patterns (DAMPs), one of which is heat shock protein 70 (Hsp70). METHODS Two models of tumor repopulation were employed, based on minimal population of cancer cells and application of conditioned medium (CM). To deplete the CMs of Hsp70 affinity chromatography on ATP-agarose and immunoprecipitation were used. Cell proliferation and the dynamics of cell growth were measured using MTT assay and xCELLigence technology; cell growth markers were estimated using qPCR and with the aid of ELISA for prostaglandin E detection. Immunoprecipitation followed by mass-spectrometry was employed to identify Hsp70-binding proteins and protein-protein interaction assays were developed to reveal the above protein complexes. RESULTS It was found that CM of dying tumor cells contains tumor regrowth-initiating factors and the removal of one of them, Hsp70, caused a reduction in the relapse-activating capacity. The pull out of Hsp70 alone using ATP-agarose had no effect on repopulation, while the immunodepletion of Hsp70 dramatically reduced its repopulation activity. Using proteomic and immunochemical approaches, we showed that Hsp70 in conditioned medium binds and binds another abundant alarmin, the High Mobility Group B1 (HMGB1) protein; the complex is formed in tumor cells treated with anti-cancer drugs, persists in the cytosol and is further released from dying tumor cells. Recurrence-activating power of Hsp70-HMGB1 complex was proved by the enhanced expression of proliferation markers, Ki67, Aurka and MCM-10 as well as by increase of prostaglandin E production and autophagy activation. Accordingly, dissociating the complex with Hsp70 chaperone inhibitors significantly inhibited the pro-growth effects of the above complex, in both in vitro and in vivo tumor relapse models. CONCLUSIONS These data led us to suggest that the abundance of the Hsp70-HMGB1 complex in the extracellular matrix may serve as a novel marker of relapse state in cancer patients, while specific targeting of the complex may be promising in the treatment of cancers with a high risk of recurrence.
Collapse
Affiliation(s)
- Dmitry V Sverchinsky
- Department of Molecular and Cellular Interaction, Institute of Cytology of Russian Academy of Sciences, Tikhoretsky prospect, 4, St. Petersburg, 194064, Russia
| | - Bashar A Alhasan
- Department of Molecular and Cellular Interaction, Institute of Cytology of Russian Academy of Sciences, Tikhoretsky prospect, 4, St. Petersburg, 194064, Russia
| | - Marina A Mikeladze
- Department of Molecular and Cellular Interaction, Institute of Cytology of Russian Academy of Sciences, Tikhoretsky prospect, 4, St. Petersburg, 194064, Russia
| | - Vladimir F Lazarev
- Department of Molecular and Cellular Interaction, Institute of Cytology of Russian Academy of Sciences, Tikhoretsky prospect, 4, St. Petersburg, 194064, Russia
| | - Liubov S Kuznetcova
- Department of Molecular and Cellular Interaction, Institute of Cytology of Russian Academy of Sciences, Tikhoretsky prospect, 4, St. Petersburg, 194064, Russia
| | - Alisa V Morshneva
- Department of Molecular and Cellular Interaction, Institute of Cytology of Russian Academy of Sciences, Tikhoretsky prospect, 4, St. Petersburg, 194064, Russia
| | - Alina D Nikotina
- Department of Molecular and Cellular Interaction, Institute of Cytology of Russian Academy of Sciences, Tikhoretsky prospect, 4, St. Petersburg, 194064, Russia
| | - Amr Ziewanah
- Department of Molecular and Cellular Interaction, Institute of Cytology of Russian Academy of Sciences, Tikhoretsky prospect, 4, St. Petersburg, 194064, Russia
- University of Kaiserslautern, Erwin-Schrödinger-Straße 52, 67663, Kaiserslautern, Germany
| | - Lidia V Koludarova
- Department of Molecular and Cellular Interaction, Institute of Cytology of Russian Academy of Sciences, Tikhoretsky prospect, 4, St. Petersburg, 194064, Russia
- Institute of Biotechnology, University of Helsinki, Viikinkaari 5, Biocenter 2, Helsinki, 00790, Finland
| | - Tatiana Y Starkova
- Department of Molecular and Cellular Interaction, Institute of Cytology of Russian Academy of Sciences, Tikhoretsky prospect, 4, St. Petersburg, 194064, Russia
| | - Boris A Margulis
- Department of Molecular and Cellular Interaction, Institute of Cytology of Russian Academy of Sciences, Tikhoretsky prospect, 4, St. Petersburg, 194064, Russia
| | - Irina V Guzhova
- Department of Molecular and Cellular Interaction, Institute of Cytology of Russian Academy of Sciences, Tikhoretsky prospect, 4, St. Petersburg, 194064, Russia.
| |
Collapse
|
2
|
Ambrose AJ, Chapman E. Function, Therapeutic Potential, and Inhibition of Hsp70 Chaperones. J Med Chem 2021; 64:7060-7082. [PMID: 34009983 DOI: 10.1021/acs.jmedchem.0c02091] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Hsp70s are among the most highly conserved proteins in all of biology. Through an iterative binding and release of exposed hydrophobic residues on client proteins, Hsp70s can prevent aggregation and promote folding to the native state of their client proteins. The human proteome contains eight canonical Hsp70s. Because Hsp70s are relatively promiscuous they play a role in folding a large proportion of the proteome. Hsp70s are implicated in disease through their ability to regulate protein homeostasis. In recent years, researchers have attempted to develop selective inhibitors of Hsp70 isoforms to better understand the role of individual isoforms in biology and as potential therapeutics. Selective inhibitors have come from rational design, forced localization, and serendipity, but the development of completely selective inhibitors remains elusive. In the present review, we discuss the Hsp70 structure and function, the known Hsp70 client proteins, the role of Hsp70s in disease, and current efforts to discover Hsp70 modulators.
Collapse
Affiliation(s)
- Andrew J Ambrose
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, 1703 East Mabel Street, Tucson, Arizona 85721, United States
| | - Eli Chapman
- Department of Pharmacology and Toxicology, College of Pharmacy, University of Arizona, 1703 East Mabel Street, Tucson, Arizona 85721, United States
| |
Collapse
|
3
|
Uwada J, Mukai S, Terada N, Nakazawa H, Islam MS, Nagai T, Fujii M, Yamasaki K, Taniguchi T, Kamoto T, Yazawa T. Pleiotropic effects of probenecid on three-dimensional cultures of prostate cancer cells. Life Sci 2021; 278:119554. [PMID: 33932444 DOI: 10.1016/j.lfs.2021.119554] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 04/19/2021] [Accepted: 04/24/2021] [Indexed: 12/30/2022]
Abstract
AIMS Chemoresistance remains a persistent challenge in advanced prostate cancer therapy. Probenecid reportedly inhibits multiple drug-efflux transporters; hence, it can be employed as a potential sensitizer for chemotherapy. In the present study, we evaluated the effects of probenecid on three-dimensional (3D)-cultures of prostate cancer cells. MAIN METHODS Prostate cancer cell lines, 22Rv1 and PC-3 were cultured as multicellular tumor spheroids. The effects of probenecid were evaluated using the MTT assay for viability, microscopy for spheroid size, and soft agar colony formation assay for anchorage-independent growth. KEY FINDINGS The 3D-cultured 22Rv1 cells were less sensitive to cisplatin and doxorubicin than two-dimensional (2D) cell culture. Co-administration of probenecid at a low (100 or 300 μM), but not high (500 μM), concentration increased the sensitivity to cisplatin or doxorubicin in 22Rv1 spheroids. Probenecid increased the expression of ABCG2, a multidrug resistance transporter, in a dose-dependent manner. Furthermore, treatment with probenecid alone reduced the growth of 22Rv1 spheroids. Conversely, probenecid inhibited spheroid compaction rather than growth inhibition in 3D-cultured PC-3 cells. Moreover, probenecid inhibited colony formation of 22Rv1 and PC-3 cells in soft agar, as well as downregulated focal adhesion kinase (FAK), a crucial factor in anchorage-independent growth. SIGNIFICANCE In 3D-cultured prostate cancer cells, probenecid demonstrated pleiotropic effects such as chemosensitization, growth suppression, inhibition of spheroid compaction, and suppression of anchorage-independent growth. Elucidating the detailed mechanism underlying these probenecid actions could result in the identification of novel therapeutic targets toward the advanced prostate cancer.
Collapse
Affiliation(s)
- Junsuke Uwada
- Department of Biochemistry, Asahikawa Medical University, Asahikawa 078-8510, Japan.
| | - Shoichiro Mukai
- Department of Urology, Faculty of Medicine, University of Miyazaki, Kiyotake, Miyazaki 889-1692, Japan
| | - Naoki Terada
- Department of Urology, Faculty of Medicine, University of Miyazaki, Kiyotake, Miyazaki 889-1692, Japan
| | - Hitomi Nakazawa
- Department of Functional Anatomy and Neuroscience, Asahikawa Medical University, Asahikawa 078-8510, Japan
| | | | - Takahiro Nagai
- Department of Urology, Faculty of Medicine, University of Miyazaki, Kiyotake, Miyazaki 889-1692, Japan
| | - Masato Fujii
- Department of Urology, Faculty of Medicine, University of Miyazaki, Kiyotake, Miyazaki 889-1692, Japan
| | - Koji Yamasaki
- Department of Urology, Faculty of Medicine, University of Miyazaki, Kiyotake, Miyazaki 889-1692, Japan
| | | | - Toshiyuki Kamoto
- Department of Urology, Faculty of Medicine, University of Miyazaki, Kiyotake, Miyazaki 889-1692, Japan
| | - Takashi Yazawa
- Department of Biochemistry, Asahikawa Medical University, Asahikawa 078-8510, Japan
| |
Collapse
|
4
|
Yang X, Gao Y, Zhao M, Wang X, Zhou H, Zhang A. Cloning and identification of grass carp transcription factor HSF1 and its characterization involving the production of fish HSP70. FISH PHYSIOLOGY AND BIOCHEMISTRY 2020; 46:1933-1945. [PMID: 32627093 DOI: 10.1007/s10695-020-00842-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Accepted: 06/18/2020] [Indexed: 06/11/2023]
Abstract
In mammals, heat shock transcription factor 1 (HSF1) is well documented as the critical transcript factor to regulate heat shock protein 70 (HSP70) expression under different stresses, such as heat shock or bacterial infection. In fish, Hsf1 responses to physiological and environmental stresses and regulates Hsp70 expression under thermal exposure. However, the functional role of Hsf1 in Hsp70 production is still elusive under bacterial infection. In the present study, a coding sequence of grass carp hsf1 (gchsf1) gene was cloned and identified. Using Ctenopharyngodon idellus kidney (CIK) cells as the model, we found that lipopolysaccharide (LPS) exerted stimulatory effects on the expression of grass carp hsp70 (gchsp70) and hsf1, implying possible relationship of Hsp70 and Hsf1 under immune stimulation in fish. To validate the hypothesis, overexpression of gcHsf1 was performed in CIK cells, and the effects of overexpressing gcHsf1 on the expression of gcHsp70 in the absence or presence of LPS were examined. Results showed that LPS significantly upregulated the transcription and protein synthesis of gcHsp70, and these stimulatory effects were further amplified when overexpression of gcHsf1 was performed. Furthermore, luciferase reporter assays in CIK cells revealed that both overexpression of Hsf1 and LPS upregulated gchsp70 transcription, and their combined treatment further enhanced the gchsp70 promoter activity. Moreover, the regions responsive to these treatments were mapped to the promoter of gchsp70. Besides transcriptional level and cellular protein contents, gcHsp70 secretion was measured by competitive ELISA, uncovering that gcHsf1 enhanced the release of gcHsp70 induced by LPS in the same cells. These data not only demonstrated the enhancement of Hsf1 in Hsp70 production but also initially revealed the involvement of Hsf1-Hsp70 axis in mediating inflammatory response in fish.
Collapse
Affiliation(s)
- Xinrui Yang
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, 610054, People's Republic of China
- Department of Biology, Lawrence University, Appleton, WI, USA
| | - Yajun Gao
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, 610054, People's Republic of China
| | - Minghui Zhao
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, 610054, People's Republic of China
| | - Xinyan Wang
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, 610054, People's Republic of China
| | - Hong Zhou
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, 610054, People's Republic of China
| | - Anying Zhang
- School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, 610054, People's Republic of China.
| |
Collapse
|
5
|
Distinct expression and localization patterns of HSP70 in developmental reproductive organs of rams. Gene 2020; 760:145029. [PMID: 32758578 DOI: 10.1016/j.gene.2020.145029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 07/15/2020] [Accepted: 08/01/2020] [Indexed: 11/21/2022]
Abstract
Heat shock protein 70 (HSP70) has been widely reported to play a vital role in maintaining intracellular homeostasis, mainly through cellular protection and immune regulation. The expression and function of HSP70 can vary depending upon species and age. To explore the expression signatures and regulatory functions of HSP70 in the reproductive organs of male sheep, we evaluated the expression and distribution patterns of HSP70 in the testes and epididymides (caput, corpus, and cauda) of Tibetan sheep at three developmental stages (i.e., 3 months, 1 year and 3 years after birth) by qRT-PCR, Western blot and immunofluorescence. HSP70 was found to be expressed in testes, caput, corpus, and cauda epididymides throughout the developmental stages but is mainly expressed postpuberty (1 year and 3 years old). Immunofluorescence results revealed that in the testes, a positive reaction for HSP70 protein was mainly seen in round spermatids and luminal sperms from the groups aged 1 year and 3 years. In caput epididymides, the positive signals for HSP70 protein was notably observed in sperm and principal cells of the epididymal epithelium from the groups aged 1 year and 3 years, and positive signals in the epididymal interstitium were found in all three age groups. In corpus and cauda epididymides, HSP70 protein was present in the epididymal epithelium and interstitium, and the positive signals gradually increased with age. In conclusion, these findings suggest that Tibetan sheep HSP70 may play a crucial role in further development and maturation of postmeiotic germ cells and participate in regulation of intraepididymal homeostasis maintenance in Tibetan sheep.
Collapse
|
6
|
Albakova Z, Armeev GA, Kanevskiy LM, Kovalenko EI, Sapozhnikov AM. HSP70 Multi-Functionality in Cancer. Cells 2020; 9:cells9030587. [PMID: 32121660 PMCID: PMC7140411 DOI: 10.3390/cells9030587] [Citation(s) in RCA: 117] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 02/20/2020] [Accepted: 02/28/2020] [Indexed: 12/20/2022] Open
Abstract
The 70-kDa heat shock proteins (HSP70s) are abundantly present in cancer, providing malignant cells selective advantage by suppressing multiple apoptotic pathways, regulating necrosis, bypassing cellular senescence program, interfering with tumor immunity, promoting angiogenesis and supporting metastasis. This direct involvement of HSP70 in most of the cancer hallmarks explains the phenomenon of cancer "addiction" to HSP70, tightly linking tumor survival and growth to the HSP70 expression. HSP70 operates in different states through its catalytic cycle, suggesting that it can multi-function in malignant cells in any of these states. Clinically, tumor cells intensively release HSP70 in extracellular microenvironment, resulting in diverse outcomes for patient survival. Given its clinical significance, small molecule inhibitors were developed to target different sites of the HSP70 machinery. Furthermore, several HSP70-based immunotherapy approaches were assessed in clinical trials. This review will explore different roles of HSP70 on cancer progression and emphasize the importance of understanding the flexibility of HSP70 nature for future development of anti-cancer therapies.
Collapse
Affiliation(s)
- Zarema Albakova
- Department of Biology, Lomonosov Moscow State University, 119192 Moscow, Russia; (G.A.A.); (A.M.S.)
- Department of Immunology, Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, 117997 Moscow, Russia; (L.M.K.); (E.I.K.)
- Correspondence:
| | - Grigoriy A. Armeev
- Department of Biology, Lomonosov Moscow State University, 119192 Moscow, Russia; (G.A.A.); (A.M.S.)
| | - Leonid M. Kanevskiy
- Department of Immunology, Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, 117997 Moscow, Russia; (L.M.K.); (E.I.K.)
| | - Elena I. Kovalenko
- Department of Immunology, Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, 117997 Moscow, Russia; (L.M.K.); (E.I.K.)
| | - Alexander M. Sapozhnikov
- Department of Biology, Lomonosov Moscow State University, 119192 Moscow, Russia; (G.A.A.); (A.M.S.)
- Department of Immunology, Shemyakin and Ovchinnikov Institute of Bioorganic Chemistry of the Russian Academy of Sciences, 117997 Moscow, Russia; (L.M.K.); (E.I.K.)
| |
Collapse
|
7
|
Srivastava S, Vishwanathan V, Birje A, Sinha D, D'Silva P. Evolving paradigms on the interplay of mitochondrial Hsp70 chaperone system in cell survival and senescence. Crit Rev Biochem Mol Biol 2020; 54:517-536. [PMID: 31997665 DOI: 10.1080/10409238.2020.1718062] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The role of mitochondria within a cell has grown beyond being the prime source of cellular energy to one of the major signaling platforms. Recent evidence provides several insights into the crucial roles of mitochondrial chaperones in regulating the organellar response to external triggers. The mitochondrial Hsp70 (mtHsp70/Mortalin/Grp75) chaperone system plays a critical role in the maintenance of proteostasis balance in the organelle. Defects in mtHsp70 network result in attenuated protein transport and misfolding of polypeptides leading to mitochondrial dysfunction. The functions of Hsp70 are primarily governed by J-protein cochaperones. Although human mitochondria possess a single Hsp70, its multifunctionality is characterized by the presence of multiple specific J-proteins. Several studies have shown a potential association of Hsp70 and J-proteins with diverse pathological states that are not limited to their canonical role as chaperones. The role of mitochondrial Hsp70 and its co-chaperones in disease pathogenesis has not been critically reviewed in recent years. We evaluated some of the cellular interfaces where Hsp70 machinery associated with pathophysiological conditions, particularly in context of tumorigenesis and neurodegeneration. The mitochondrial Hsp70 machinery shows a variable localization and integrates multiple components of the cellular processes with varied phenotypic consequences. Although Hsp70 and J-proteins function synergistically in proteins folding, their precise involvement in pathological conditions is mainly idiosyncratic. This machinery is associated with a heterogeneous set of molecules during the progression of a disorder. However, the precise binding to the substrate for a specific physiological response under a disease subtype is still an undocumented area of analysis.
Collapse
Affiliation(s)
- Shubhi Srivastava
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | | | - Abhijit Birje
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| | - Devanjan Sinha
- Department of Zoology, Institute of Science, Banaras Hindu University, Varanasi, India
| | - Patrick D'Silva
- Department of Biochemistry, Indian Institute of Science, Bangalore, India
| |
Collapse
|
8
|
Meshalkina DA, Shevtsov MA, Dobrodumov AV, Komarova EY, Voronkina IV, Lazarev VF, Margulis BA, Guzhova IV. Knock-down of Hdj2/DNAJA1 co-chaperone results in an unexpected burst of tumorigenicity of C6 glioblastoma cells. Oncotarget 2017; 7:22050-63. [PMID: 26959111 PMCID: PMC5008343 DOI: 10.18632/oncotarget.7872] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 02/20/2016] [Indexed: 01/04/2023] Open
Abstract
The chaperone system based on Hsp70 and proteins of the DnaJ family is known to protect tumor cells from a variety of cytotoxic factors, including anti-tumor therapy. To analyze whether this also functions in a highly malignant brain tumor, we knocked down the expression of Hsp70 (HSPA1A) and its two most abundant co-chaperones, Hdj1 (DNAJB1) and Hdj2 (DNAJA1) in a C6 rat glioblastoma cell line. As expected, tumor depletion of Hsp70 caused a substantial reduction in its growth rate and increased the survival of tumor-bearing animals, whereas the reduction of Hdj1 expression had no effect. Unexpectedly, a reduction in the expression of Hdj2 led to the enhanced aggressiveness of the C6 tumor, demonstrated by its rapid growth, metastasis formation and a 1.5-fold reduction in the lifespan of tumor-bearing animals. The in vitro reduction of Hdj2 expression reduced spheroid density and simultaneously enhanced the migration and invasion of C6 cells. At the molecular level, a knock-down of Hdj2 led to the relocation of N-cadherin and the enhanced activity of metalloproteinases 1, 2, 8 and 9, which are markers of highly malignant cancer cells. The changes in the actin cytoskeleton in Hdj2-depleted cells indicate that the protein is also important for prevention of the amoeboid-like transition of tumor cells. The results of this study uncover a completely new role for the Hdj2 co-chaperone in tumorigenicity and suggest that the protein is a potential drug target.
Collapse
Affiliation(s)
- Darya A Meshalkina
- Institute of Cytology of Russian Academy of Sciences, St. Petersburg 194064, Russia
| | - Maxim A Shevtsov
- Institute of Cytology of Russian Academy of Sciences, St. Petersburg 194064, Russia.,First I.P. Pavlov State Medical University of St. Petersburg, St. Petersburg 197022, Russia
| | - Anatoliy V Dobrodumov
- Institute of Macromolecular Compounds of the Russian Academy of Sciences, St. Petersburg 199004, Russia
| | - Elena Y Komarova
- Institute of Cytology of Russian Academy of Sciences, St. Petersburg 194064, Russia
| | - Irina V Voronkina
- Institute of Cytology of Russian Academy of Sciences, St. Petersburg 194064, Russia
| | - Vladimir F Lazarev
- Institute of Cytology of Russian Academy of Sciences, St. Petersburg 194064, Russia
| | - Boris A Margulis
- Institute of Cytology of Russian Academy of Sciences, St. Petersburg 194064, Russia
| | - Irina V Guzhova
- Institute of Cytology of Russian Academy of Sciences, St. Petersburg 194064, Russia
| |
Collapse
|
9
|
Radons J. The human HSP70 family of chaperones: where do we stand? Cell Stress Chaperones 2016; 21:379-404. [PMID: 26865365 PMCID: PMC4837186 DOI: 10.1007/s12192-016-0676-6] [Citation(s) in RCA: 358] [Impact Index Per Article: 44.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Revised: 01/29/2016] [Accepted: 01/29/2016] [Indexed: 01/23/2023] Open
Abstract
The 70-kDa heat shock protein (HSP70) family of molecular chaperones represents one of the most ubiquitous classes of chaperones and is highly conserved in all organisms. Members of the HSP70 family control all aspects of cellular proteostasis such as nascent protein chain folding, protein import into organelles, recovering of proteins from aggregation, and assembly of multi-protein complexes. These chaperones augment organismal survival and longevity in the face of proteotoxic stress by enhancing cell viability and facilitating protein damage repair. Extracellular HSP70s have a number of cytoprotective and immunomodulatory functions, the latter either in the context of facilitating the cross-presentation of immunogenic peptides via major histocompatibility complex (MHC) antigens or in the context of acting as "chaperokines" or stimulators of innate immune responses. Studies have linked the expression of HSP70s to several types of carcinoma, with Hsp70 expression being associated with therapeutic resistance, metastasis, and poor clinical outcome. In malignantly transformed cells, HSP70s protect cells from the proteotoxic stress associated with abnormally rapid proliferation, suppress cellular senescence, and confer resistance to stress-induced apoptosis including protection against cytostatic drugs and radiation therapy. All of the cellular activities of HSP70s depend on their adenosine-5'-triphosphate (ATP)-regulated ability to interact with exposed hydrophobic surfaces of proteins. ATP hydrolysis and adenosine diphosphate (ADP)/ATP exchange are key events for substrate binding and Hsp70 release during folding of nascent polypeptides. Several proteins that bind to distinct subdomains of Hsp70 and consequently modulate the activity of the chaperone have been identified as HSP70 co-chaperones. This review focuses on the regulation, function, and relevance of the molecular Hsp70 chaperone machinery to disease and its potential as a therapeutic target.
Collapse
Affiliation(s)
- Jürgen Radons
- Scientific Consulting International, Mühldorfer Str. 64, 84503, Altötting, Germany.
| |
Collapse
|
10
|
Graham ZA, Touchberry CD, Gupte AA, Bomhoff GL, Geiger PC, Gallagher PM. Changes in α7β1 integrin signaling after eccentric exercise in heat-shocked rat soleus. Muscle Nerve 2015; 51:562-8. [PMID: 24956997 DOI: 10.1002/mus.24324] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/18/2014] [Indexed: 12/16/2022]
Abstract
INTRODUCTION α7β1 integrin links the extracellular matrix to the focal adhesion (FA) in skeletal muscle and serves as a stabilizing and signal relayer. Heat shock (HS) induces expression of proteins that interact with the FA. METHODS Male Wistar rats were assigned to 1 of 3 groups: control (CON); eccentric exercise (EE); or EE+HS (HS). Soleus muscle was analyzed at 2 h and 48 h post-exercise. RESULTS The 120-kDa α7 integrin decreased in the EE and HS groups, and the 70-kDa peptide decreased in the EE group at 2 h post-exercise. Total expression of focal adhesion kinase (FAK) and RhoA were decreased in EE and HS at 2 h post-exercise. Expression of phosphorylated FAK(397) decreased in the EE group but not the HS group at 2 h post-exercise. CONCLUSIONS Long-duration EE may cause alterations in the FA in rat soleus muscle through the α7 integrin subunit and FAK.
Collapse
Affiliation(s)
- Zachary A Graham
- Applied Physiology Laboratory, Department of Health, Sport, and Exercise Sciences, University of Kansas, 101DJ Robinson Center, 1301 Sunnyside Avenue, Lawrence, Kansas, 66045, USA
| | | | | | | | | | | |
Collapse
|
11
|
Bosch A, Panoutsopoulou K, Corominas JM, Gimeno R, Moreno-Bueno G, Martín-Caballero J, Morales S, Lobato T, Martínez-Romero C, Farias EF, Mayol X, Cano A, Hernández-Muñoz I. The Polycomb group protein RING1B is overexpressed in ductal breast carcinoma and is required to sustain FAK steady state levels in breast cancer epithelial cells. Oncotarget 2015; 5:2065-76. [PMID: 24742605 PMCID: PMC4039145 DOI: 10.18632/oncotarget.1779] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
In early stages of metastasis malignant cells must acquire phenotypic changes to enhance their migratory behavior and their ability to breach the matrix surrounding tumors and blood vessel walls. Epigenetic regulation of gene expression allows the acquisition of these features that, once tumoral cells have escape from the primary tumor, can be reverted. Here we report that the expression of the Polycomb epigenetic repressor Ring1B is enhanced in tumoral cells that invade the stroma in human ductal breast carcinoma and its expression is coincident with that of Fak in these tumors. Ring1B knockdown in breast cancer cell lines revealed that Ring1B is required to sustain Fak expression in basal conditions as well as in Tgfβ-treated cells. Functionally, endogenous Ring1B is required for cell migration and invasion in vitro and for in vivo invasion of the mammary fat pad by tumoral cells. Finally we identify p63 as a target of Ring1B to regulate Fak expression: Ring1B depletion results in enhanced p63 expression, which in turns represses Fak expression. Importantly, Fak downregulation upon Ring1B depletion is dependent on p63 expression. Our findings provide new insights in the biology of the breast carcinoma and open new avenues for breast cancer prognosis and therapy.
Collapse
Affiliation(s)
- Almudena Bosch
- Cancer Research Program. IMIM (Institut Hospital del Mar d'Investigacions Mèdiques). Barcelona. Spain
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
12
|
The complex function of hsp70 in metastatic cancer. Cancers (Basel) 2013; 6:42-66. [PMID: 24362507 PMCID: PMC3980608 DOI: 10.3390/cancers6010042] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Revised: 12/05/2013] [Accepted: 12/11/2013] [Indexed: 12/26/2022] Open
Abstract
Elevated expression of the inducible heat shock protein 70 (Hsp70) is known to correlate with poor prognosis in many cancers. Hsp70 confers survival advantage as well as resistance to chemotherapeutic agents, and promotes tumor cell invasion. At the same time, tumor-derived extracellular Hsp70 has been recognized as a "chaperokine", activating antitumor immunity. In this review we discuss localization dependent functions of Hsp70 in the context of invasive cancer. Understanding the molecular principles of metastasis formation steps, as well as interactions of the tumor cells with the microenvironment and the immune system is essential for fighting metastatic cancer. Although Hsp70 has been implicated in different steps of the metastatic process, the exact mechanisms of its action remain to be explored. Known and potential functions of Hsp70 in controlling or modulating of invasion and metastasis are discussed.
Collapse
|
13
|
Nguyen N, Yi JS, Park H, Lee JS, Ko YG. Mitsugumin 53 (MG53) ligase ubiquitinates focal adhesion kinase during skeletal myogenesis. J Biol Chem 2013; 289:3209-16. [PMID: 24344130 DOI: 10.1074/jbc.m113.525154] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The striated muscle-specific mitsugumin 53 (MG53) is a novel E3 ligase that induces the ubiquitination of insulin receptor substrate 1 (IRS-1) during skeletal myogenesis, negatively regulating insulin-like growth factor and insulin signaling. Here we show that focal adhesion kinase (FAK) is the second target of MG53 during skeletal myogenesis. The FAK protein level gradually decreased, whereas its mRNA level was constant during myogenesis in C2C12 cells and MyoD-overexpressing mouse embryonic fibroblasts. The FAK protein was associated with the E2 enzyme UBE2H and the E3 enzyme MG53 in endogenous and exogenous immunoprecipitation experiments. FAK ubiquitination and degradation was induced by MG53 overexpression in myoblasts but abolished by MG53 or UBE2H knockdown in myotubes. Because RING-disrupted MG53 mutants (C14A and ΔR) did not induce FAK ubiquitination and degradation, the RING domain was determined to be required for MG53-induced FAK ubiquitination. Taken together, these data indicate that MG53 induces FAK ubiquitination with the aid of UBE2H during skeletal myogenesis.
Collapse
Affiliation(s)
- Nga Nguyen
- From the Division of Life Sciences, Korea University, Seoul 136-701, Korea
| | | | | | | | | |
Collapse
|
14
|
Effects of decorin and biglycan on human airway smooth muscle cell adhesion. Matrix Biol 2012; 31:101-12. [DOI: 10.1016/j.matbio.2011.11.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Revised: 11/01/2011] [Accepted: 11/09/2011] [Indexed: 01/01/2023]
|
15
|
Li G, Xu Y, Guan D, Liu Z, Liu DX. HSP70 protein promotes survival of C6 and U87 glioma cells by inhibition of ATF5 degradation. J Biol Chem 2011; 286:20251-9. [PMID: 21521685 DOI: 10.1074/jbc.m110.211771] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Although both the heat shock protein 70 (HSP70) and the activating transcription factor 5 (ATF5) have been shown to promote cell survival of transformed cells but not survival of non-transformed cells, the relationship of the two molecules is unknown. Here we show that HSP70 and ATF5 are concomitantly up-regulated upon transient but down-regulated over prolonged cellular stress and apoptotic stimulation in the rat C6 glioma and human U87 glioma cells. HSP70 interacts strongly with the N-terminal activation domain of ATF5, which is expected to be rigid and uniquely structured under physiological conditions because of extraordinary high concentration (over 25%) of proline residues. Binding of HSP70 to ATF5 is an ATP-driven process and requires functional ATPase on the nucleotide binding domain of the HSP70 molecule. Overexpression of HSP70 dramatically stabilizes the ATF5 protein, which is otherwise subject to rapid degradation, facilitated by both proteasome-dependent and caspase-dependent processes, whereas HSP70 depletion leads to acceleration of ATF5 degradation and transcription repression of Bcl-2 and Egr-1, which are downstream targets of ATF5 in C6 and U87 glioma cells. Our data reveal an essential role for HSP70 in maintaining high levels of ATF5 expression in glioma cells and support the conclusion that ATF5 is an important substrate protein of HSP70 that mediates HSP70-promoted cell survival in glioma cells.
Collapse
Affiliation(s)
- Guangfu Li
- Department of Neural and Behavioral Sciences, Penn State University College of Medicine, Hershey, Pennsylvania 17033, USA
| | | | | | | | | |
Collapse
|
16
|
Sivaswamy S, Neafsey EJ, Collins MA. Neuroprotective preconditioning of rat brain cultures with ethanol: potential transduction by PKC isoforms and focal adhesion kinase upstream of increases in effector heat shock proteins. Eur J Neurosci 2010; 32:1800-12. [DOI: 10.1111/j.1460-9568.2010.07451.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
|
17
|
Xie J, Zhao J, Xiao C, Xu Y, Yang S, Ni W. Reduced heat shock protein 70 in airway smooth muscle in patients with chronic obstructive pulmonary disease. Exp Lung Res 2010; 36:219-26. [PMID: 20426530 DOI: 10.3109/01902140903349562] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Studies demonstrated that pathophysiological abnormalities of airway smooth muscle (ASM) contribute significantly to chronic obstructive pulmonary disease (COPD) pathogenesis, the aim of this study is to investigate heat shock protein 70 (Hsp70) in ASM in COPD. ASM from 8 COPD patients and 6 controls were isolated for detection of Hsp70 using Western blot. Male adult Wister rats were exposed to mixture of cigarette smoke/air or room air for an indicated period. The lung tissues were obtained for pathological analysis, and ASM were dissected for Hsp70 detection. Normalized Hsp70 in ASM from COPD patients was significantly lower than that from controls (P <.001), and it was a significant positive correlation of Hsp70 and lung function. One-month exposure of rats to cigarette smoke/air mixture led to increased expression of Hsp70 and heat shock transcription factor (Hsf1) in ASM as compared to controls, whereas 3-month exposure caused dramatically reduced Hsp70 and Hsf1 than control animals. In addition, 3-month exposure to cigarette smoke/air mixture resulted in significantly lower Hsp70 and Hsf1 in rats ASM than 1-month exposure (P <.001), and it was a positive correlation of Hsf1 and Hsp70. Long-term cigarette smoking results in reduced expression of Hsp70 in ASM. This finding provides additional insight in understanding molecular changes in ASM during COPD pathogenesis.
Collapse
Affiliation(s)
- Jungang Xie
- 1Department of Respiratory Medicine, Tongji Hospital Affiliated to Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, PR China.
| | | | | | | | | | | |
Collapse
|
18
|
Fleshner M, Johnson JD. Endogenous extra-cellular heat shock protein 72: Releasing signal(s) and function. Int J Hyperthermia 2009; 21:457-71. [PMID: 16048842 DOI: 10.1080/02656730500088211] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Exposure to acute physical and/or psychological stressors induces a cascade of physiological changes collectively termed the stress response. The stress response is demonstrable at the behavioural, neural, endocrine and cellular levels. Stimulation of the stress response functions to improve an organism's chance of survival during acute stressor challenge. The current review focuses on one ubiquitous cellular stress response, up-regulation of heat shock protein 72 (Hsp72). Although a great deal is known about the function of intra-cellular Hsp72 during exposure to acute stressors, little is understood about the potential function of endogenous extra-cellular Hsp72 (eHsp72). The current review will develop the hypothesis that eHsp72 release may be a previously unrecognized feature of the acute stress response and may function as an endogenous 'danger signal' for the immune system. Specifically, it is proposed that exposure to physical or psychological acute stressors stimulate the release of endogenous eHsp72 into the blood via an alpha1-adrenergic receptor-mediated mechanism and that elevated eHsp72 functions to facilitate innate immunity in the presence of bacterial challenge.
Collapse
Affiliation(s)
- M Fleshner
- Department of Integrative Physiology, University of Colorado-Bouler, CO 80309-0354, USA.
| | | |
Collapse
|
19
|
|
20
|
Guan X, Dei-Anane G, Bruns H, Chen J, Nickkholgh A, Liang R, Gross ML, Kern M, Ludwig J, Büchler MW, Schemmer P. Danshen protects kidney grafts from ischemia/reperfusion injury after experimental transplantation. Transpl Int 2008; 22:232-41. [PMID: 18954374 DOI: 10.1111/j.1432-2277.2008.00770.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Danshen (DS) is used for treatment of various ischemic events in the traditional Chinese medicine. Hence, this study was designed to investigate its effect on ischemia/reperfusion injury (IRI) after experimental kidney transplantation (eKTx). Nephrectomized Sprague-Dawley rats underwent eKTx. Some animals were infused with 1.5 ml DS 10 min before surgery. Kidney grafts were transplanted after cold storage for 20 h in Histidine-Tryptophane-Ketoglutarate solution. After reperfusion blood samples were collected for blood urinary nitrogen (BUN), creatinine, lactate dehydrogenase (LDH), and alanine transaminase. Further, tissue was assessed for morphologic and pathophysiologic changes. Donor preconditioning with DS (DS-d) significantly decreased BUN, creatinine, LDH, and aspartate aminotransferase to 65-97% of controls while preconditioning of the recipient (DS-r) decreased values to 58-82% (P < 0.05). Tubular damage and caspase-3 decreased significantly in both DS-d and DS-r (DS-d: 96% and 67%, DS-r: 83% and 75% of controls) while heat shock protein 72 and superoxide dismutase increased significantly (DS-d: 143% and 173%, DS-r: 166% and 194% of controls). Further, inducible nitric oxide synthase and tumor necrosis factor-alpha decreased (DS-d: 84% and 61%, DS-r: 79% and 67% of controls) after DS. Preconditioning of both donors and recipients with DS significantly reduces IRI and thus improves graft function after eKTx.
Collapse
Affiliation(s)
- Xiaohai Guan
- Department of General Surgery, Ruprecht-Karls-University, Heidelberg, Germany
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Chen PY, Lee KT, Chi WC, Hirt H, Chang CC, Huang HJ. Possible involvement of MAP kinase pathways in acquired metal-tolerance induced by heat in plants. PLANTA 2008; 228:499-509. [PMID: 18506480 DOI: 10.1007/s00425-008-0753-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2008] [Accepted: 05/09/2008] [Indexed: 05/26/2023]
Abstract
Cross tolerance is a phenomenon that occurs when a plant, in resisting one form of stress, develops a tolerance to another form. Pretreatment with nonlethal heat shock has been known to protect cells from metal stress. In this study, we found that the treatment of rice roots with more than 25 muM of Cu(2+) caused cell death. However, heat shock pretreatment attenuated Cu(2+)-induced cell death. The mechanisms of the cross tolerance phenomenon between heat shock and Cu(2+) stress were investigated by pretreated rice roots with the protein synthesis inhibitor cycloheximide (CHX). CHX effectively block heat shock protection, suggesting that protection of Cu(2+)-induced cell death by heat shock was dependent on de novo protein synthesis. In addition, heat pretreatment downregulated ROS production and mitogen-activated protein kinase (MAPK) activities, both of which can be greatly elicited by Cu(2+) stress in rice roots. Moreover, the addition of purified recombinant GST-OsHSP70 fusion proteins inhibited Cu(2+)-enhanced MAPK activities in an in vitro kinase assay. Furthermore, loss of heat shock protection was observed in Arabidopsis mkk2 and mpk6 but not in mpk3 mutants under Cu(2+) stress. Taken together, these results suggest that the interaction of OsHSP70 with MAPKs may contribute to the cellular protection in rice roots from excessive Cu(2+) toxicity.
Collapse
Affiliation(s)
- Po-Yu Chen
- Department of Life Sciences, National Cheng Kung University, Tainan, 701, Taiwan
| | | | | | | | | | | |
Collapse
|
22
|
Guan X, Dei-Anane G, Liang R, Gross ML, Nickkholgh A, Kern M, Ludwig J, Zeier M, Büchler MW, Schmidt J, Schemmer P. Donor Preconditioning with Taurine Protects Kidney Grafts from Injury After Experimental Transplantation. J Surg Res 2008; 146:127-34. [DOI: 10.1016/j.jss.2007.06.014] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2007] [Revised: 05/29/2007] [Accepted: 06/08/2007] [Indexed: 11/26/2022]
|
23
|
Mao H, Li Z, Zhou Y, Li Z, Zhuang S, An X, Zhang B, Chen W, Nie J, Wang Z, Borkan SC, Wang Y, Yu X. HSP72 attenuates renal tubular cell apoptosis and interstitial fibrosis in obstructive nephropathy. Am J Physiol Renal Physiol 2008; 295:F202-14. [PMID: 18417540 DOI: 10.1152/ajprenal.00468.2007] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Although heat shock protein 72 kDa (HSP72) protects tubular epithelium from a variety of acute insults, its role in chronic renal injury and fibrosis is poorly characterized. In this study, we tested the hypothesis that HSP72 reduces apoptosis and epithelial-to-mesenchymal transition (EMT), important contributors to tubular cell injury in vitro and in vivo. In rats, orally administered geranylgeranylacetone (GGA), an agent that selectively induces HSP72, markedly reduced both apoptosis and cell proliferation in tubular epithelium and decreased both interstitial fibroblast accumulation and collagen I deposition after unilateral ureteric obstruction, a model of chronic renal tubulointerstitial fibrosis and dysfunction. In cultured renal NRK52E cells, exposure to TGF-beta1 induced EMT and apoptosis, major causes of renal fibrosis and tubular atrophy, respectively. Exposure to a pan-caspase inhibitor (ZVAD-FMK) prevented TGF-beta1-induced apoptosis but did not reduce EMT. In contrast, selective HSP72 expression in vitro inhibited EMT caused by TGF-beta1 as indicated by preserving the E-cadherin expression level and alpha-smooth muscle actin induction. Small interfering RNA directed against HSP72 blocked the cytoprotective effects of HSP72 overexpression on EMT in TGF-beta1-exposed cells. Taken together, our data indicate that HSP72 ameliorates renal tubulointerstitial fibrosis in obstructive nephropathy by inhibiting both renal tubular epithelial cell apoptosis and EMT.
Collapse
Affiliation(s)
- Haiping Mao
- Department of Nephrology, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Taylor AR, Robinson MB, Gifondorwa DJ, Tytell M, Milligan CE. Regulation of heat shock protein 70 release in astrocytes: role of signaling kinases. Dev Neurobiol 2007; 67:1815-29. [PMID: 17701989 DOI: 10.1002/dneu.20559] [Citation(s) in RCA: 191] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The ability to mount a successful stress response in the face of injury is critical to the long-term viability of individual cells and to the organism in general. The stress response, characterized in part by the upregulation of heat shock proteins, is compromised in several neurodegenerative disorders and in some neuronal populations, including motoneurons (MNs). Because astrocytes have a greater capacity than neurons to survive metabolic stress, and because they are intimately associated with the regulation of neuronal function, it is important to understand their stress response, so that we may to better appreciate the impact of stress on neuronal viability during injury or disease. We show that astrocytes subjected to hyperthermia upregulate Hsp/c70 in addition to intracellular signaling components including activated forms of extracellular-signal-regulated kinase (ERK1/2), Akt, and c-jun N-terminal kinase/stress activated protein kinase (JNK/SAPK). Furthermore, astrocytes release increasing amounts of Hsp/c70 into the extracellular environment following stress, an event that is abrogated when signaling through the ERK1/2 and phosphatidylinositol-3 kinase (PI3K) pathways is compromised and enhanced by inhibition of the JNK pathway. Last, we show that the Hsp/c70 is released from astrocytes in exosomes. Together, these data illustrate the diverse regulation of stress-induced Hsp/c70 release in exosomes, and the way in which the balance of activated signal transduction pathways affects this release. These data highlight how stressful insults can alter the microenvironment of an astrocyte, which may ultimately have implications for the survival of neighboring neurons.
Collapse
Affiliation(s)
- Anna R Taylor
- Department of Neurobiology and Anatomy, Wake Forest University School of Medicine, Winston-Salem, North Carolina 27157, USA
| | | | | | | | | |
Collapse
|
25
|
van Nimwegen MJ, Huigsloot M, Camier A, Tijdens IB, van de Water B. Focal adhesion kinase and protein kinase B cooperate to suppress doxorubicin-induced apoptosis of breast tumor cells. Mol Pharmacol 2006; 70:1330-9. [PMID: 16825486 DOI: 10.1124/mol.106.026195] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Focal adhesion kinase (FAK) is up-regulated in a variety of cancers, including breast cancer, in association with poor disease prognosis. In the present study, we examined the role of FAK in the control of anticancer drug-induced apoptosis of mammary adenocarcinoma MTLn3 cells. Doxorubicin caused the formation of well defined focal adhesions and stress fibers early after treatment, which was later followed by their loss in association with the onset of apoptosis. Phosphorylation of FAK on tyrosine 397 decreased only during the onset of doxorubicin-induced apoptosis in a Bcl-2 and caspase-independent manner. Doxorubicin also caused an early activation of protein kinase B (PKB). Expression of the dominant-negative acting focal adhesion kinase-related nonkinase (FRNK) sensitized MTLn3 cells to apoptosis caused by doxorubicin. FRNK inhibited the doxorubicin-induced activation of PKB. In addition, inhibition of phosphatidylinositide-3 (PI-3) kinase with wortmannin inhibited the activation of PKB by doxorubicin. Both wortmannin and transient overexpression of the dual lipid/protein phosphatase and tensin homolog deleted on chromosome 10 enhanced doxorubicin-induced cell death. Altogether, these data fit with a model wherein FAK is involved in the doxorubicin-induced activation of the PI-3 kinase/PKB signaling route, thereby suppressing the onset of apoptosis caused by doxorubicin.
Collapse
Affiliation(s)
- Maroesja J van Nimwegen
- Division of Toxicology, LACDR, Leiden University, Einsteinweg 55, P.O. Box 9502, 2300 RA Leiden, The Netherlands
| | | | | | | | | |
Collapse
|
26
|
Wei H, Campbell W, Vander Heide RS. Heat shock-induced cardioprotection activates cytoskeletal-based cell survival pathways. Am J Physiol Heart Circ Physiol 2006; 291:H638-47. [PMID: 16565316 DOI: 10.1152/ajpheart.00144.2006] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To define better the subcellular mechanism of heat shock (HS)-induced cardioprotection, we examined the effect of HS, as well as selective expression of individual HS proteins (HSPs), on cell injury in neonatal rat ventricular myocytes (NRVM). HS was induced in NRVM by a rapid elevation of temperature to 42 degrees C for 20 min followed by 20-24 h of recovery at 37 degrees C. Other NRVM were infected with a replication-deficient adenovirus encoding HSP27 or HSP70. On the same day, all groups were subjected to metabolic inhibition (MI). Cell injury was assayed by measurement of the percentage of total lactate dehydrogenase released, the percentage of cells staining with trypan blue, or TdT-mediated dUTP nick-end labeling, whereas cell signaling was assayed by immunoblot analysis and coimmunoprecipitation. Before MI, the viability of all treated groups did not differ significantly from control NRVM. HS resulted in a significant increase in HSP70 and HSP27 expression. Infection with either virus caused a significant increase in selective HSP content compared with control NRVM. HS protected NRVM from injury. Selective expression of HSP27 or HSP70 alone was not protective in NRVM, but dual infection with both viral vectors (HSP27 + HSP70) was protective. HS and HSP27 + HSP70 expression caused increased paxillin localization in the membrane fraction, which persisted in response to MI, compared with control NRVM. HS increased the integrin-paxillin-focal adhesion kinase interaction, whereas targeted inhibition of focal adhesion kinase activity abolished the integrin-paxillin association and resulted in an increase in cell death. HS and HSP27 + HSP70 expression increased the association of members of the focal adhesion complex and protected NRVM against irreversible injury. Cytoskeletal-based signaling pathways at focal adhesion junctions may represent a unique pathway of cardioprotection.
Collapse
Affiliation(s)
- Hongguang Wei
- Department of Medicine, Wayne State University Medical School, Detroit, MI 48201, USA
| | | | | |
Collapse
|
27
|
Ruchalski K, Mao H, Li Z, Wang Z, Gillers S, Wang Y, Mosser DD, Gabai V, Schwartz JH, Borkan SC. Distinct hsp70 domains mediate apoptosis-inducing factor release and nuclear accumulation. J Biol Chem 2006; 281:7873-80. [PMID: 16407317 DOI: 10.1074/jbc.m513728200] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Although hsp70 antagonizes apoptosis-inducing factor (AIF)-mediated cell death, the relative importance of preventing its release from mitochondria versus sequestering leaked AIF in the cytosol remains controversial. To dissect these two protective mechanisms, hsp70 deletion mutants lacking either the chaperone function (hsp70-deltaEEVD) or ATPase function (hsp70-deltaATPase) were selectively overexpressed before exposing cells to a metabolic inhibitor, an insult sufficient to cause mitochondrial AIF release, nuclear AIF accumulation, and apoptosis. Compared with empty vector, overexpression of wild type human hsp70 inhibited bax activation and reduced mitochondrial AIF release after injury. In contrast, mutants lacking either the chaperone function (hsp70-deltaEEVD) or the ATP hydrolytic domain (hsp70-deltaATPase) failed to prevent mitochondrial AIF release. Although hsp70-deltaEEVD did not inhibit bax activation or mitochondrial membrane injury after cell stress, this hsp70 mutant co-immunoprecipitated with leaked AIF in injured cells and decreased nuclear AIF accumulation. In contrast, hsp70-deltaATPase did not interact with AIF either in intact cells or in a cell-free system and furthermore, failed to prevent nuclear AIF accumulation. These results demonstrate that mitochondrial protection against bax-mediated injury requires both intact chaperone and ATPase functions, whereas the ATPase domain is critical for sequestering AIF in the cytosol.
Collapse
Affiliation(s)
- Kathleen Ruchalski
- Renal Section, Department of Medicine, Boston Medical Center, Boston University, Boston, Massachusetts 02118-2518, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
28
|
Johnson JD, Fleshner M. Releasing signals, secretory pathways, and immune function of endogenous extracellular heat shock protein 72. J Leukoc Biol 2005; 79:425-34. [PMID: 16387837 DOI: 10.1189/jlb.0905523] [Citation(s) in RCA: 183] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Heat shock proteins (Hsp) were first characterized as intracellular proteins, which function to limit protein aggregation, facilitate protein refolding, and chaperone proteins. During times of cellular stress, intracellular Hsp levels increase to provide cellular protection. Recently, it has been recognized that Hsp, particularly Hsp72, are also found extracellularly (eHsp72), where they exhibit potent immunomodulatory effects on innate and acquired immunity. Circulating eHsp72 levels also greatly increase during times of stress (i.e., when an organism is exposed to a physical/psychological stressor or suffers from various pathological conditions). It has been proposed that elevated eHsp72 serves a protective role by facilitating immunological responses during times of increased risk of pathogenic challenge and/or tissue damage. This review focuses on the in vivo releasing signals and immunomodulatory function(s) of endogenous eHsp72. In addition, we present data that emphasize the importance of caution when conducting in vitro immunological tests of Hsp72 function.
Collapse
Affiliation(s)
- John D Johnson
- Department of Integrative Physiology, University of Colorado, Boulder, CO 80309-0354, USA
| | | |
Collapse
|
29
|
Beere HM. Death versus survival: functional interaction between the apoptotic and stress-inducible heat shock protein pathways. J Clin Invest 2005; 115:2633-9. [PMID: 16200196 PMCID: PMC1236700 DOI: 10.1172/jci26471] [Citation(s) in RCA: 330] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Induction of heat shock proteins (Hsps) following cellular damage can prevent apoptosis induced by both the intrinsic and the extrinsic pathways. The intrinsic pathway is characterized by mitochondrial outer membrane permeabilization (MOMP), cytochrome c release, apoptosome assembly, and caspase activation. Hsps promote cell survival by preventing MOMP or apoptosome formation as well as via regulation of Akt and JNK activities. Engagement of the TNF death receptors induces the extrinsic pathway that is characterized by Fas-associated death domain-dependent (FADD-dependent) caspase-8 activation or induction of NF-kappaB to promote cellular survival. Hsps can directly suppress proapoptotic signaling events or stabilizing elements of the NF-kappaB pathway to promote cellular survival.
Collapse
Affiliation(s)
- Helen M Beere
- St. Jude Children's Research Hospital, Department of Immunology, Memphis, Tennessee 38105, USA.
| |
Collapse
|
30
|
Watermann DO, Gabriel B, Jäger M, Orlowska-Volk M, Hasenburg A, zur Hausen A, Gitsch G, Stickeler E. Specific induction of pp125 focal adhesion kinase in human breast cancer. Br J Cancer 2005; 93:694-8. [PMID: 16136050 PMCID: PMC2361616 DOI: 10.1038/sj.bjc.6602744] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The pp125 focal adhesion kinase (FAK) is involved in integrin-mediated cell signalling and overexpressed in a variety of solid tumours. Focal adhesion kinase expression has been correlated to invasion and metastasis, but the data on breast cancer are inconclusive. We analysed FAK mRNA, protein levels and expression patterns in primary breast cancer and normal breast tissue. FAK expression on the functional protein level and mRNA was determined in 55 matched pairs of breast cancer and corresponding normal tissue by Western blot, immunohistochemistry and RT–PCR. Using a score ranging from 0 to +5 for Western blots, we determined in normal breast tissue a score of 1.51±0.84 (mean±standard deviation), which was strongly induced to 2.91 (±1.22) in breast cancers (P<0.001). Overall, 45 out of 55 tissue pairs (81.8%) showed this upregulation of FAK protein in tumours in comparison to normal tissue. Immunohistochemistry confirmed these findings with a significant higher score for tumours vs physiological tissue (1.0±0.63 vs 2.27±0.91; P=0.001). Interestingly, no overall significant difference in the mRNA levels (P=0.359) was observed. In conclusion, expression levels of the FAK protein are specifically upregulated in breast cancer in comparison to matched normal breast tissue supporting its pivotal role in neoplastic signal transduction and representing a potential marker for malignant transformation.
Collapse
Affiliation(s)
- D O Watermann
- Department of Obstetrics and Gynecology, University of Freiburg, Hugstetterstr. 55, 79106 Freiburg, Germany
| | - B Gabriel
- Department of Obstetrics and Gynecology, University of Freiburg, Hugstetterstr. 55, 79106 Freiburg, Germany
| | - M Jäger
- Department of Obstetrics and Gynecology, University of Freiburg, Hugstetterstr. 55, 79106 Freiburg, Germany
| | - M Orlowska-Volk
- Department of Pathology, University of Freiburg, 79106 Freiburg, Germany
| | - A Hasenburg
- Department of Obstetrics and Gynecology, University of Freiburg, Hugstetterstr. 55, 79106 Freiburg, Germany
| | - A zur Hausen
- Department of Pathology, University of Freiburg, 79106 Freiburg, Germany
| | - G Gitsch
- Department of Obstetrics and Gynecology, University of Freiburg, Hugstetterstr. 55, 79106 Freiburg, Germany
| | - E Stickeler
- Department of Obstetrics and Gynecology, University of Freiburg, Hugstetterstr. 55, 79106 Freiburg, Germany
- Department of Obstetrics and Gynecology, University of Freiburg, Hugstetterstr. 55, 79106 Freiburg, Germany. E-mail:
| |
Collapse
|
31
|
Wohlschlaeger J, Stubbe HD, Schmitz KJ, Kawaguchi N, Takeda A, Takeda N, Hinder F, Baba HA. Roles of MMP-2/-9 in cardiac dysfunction during early multiple organ failure in an ovine animal model. Pathol Res Pract 2005; 201:809-17. [PMID: 16308106 DOI: 10.1016/j.prp.2005.08.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2005] [Accepted: 08/31/2005] [Indexed: 11/26/2022]
Abstract
Biventricular dilation and severe cardiac dysfunction are observed during septic shock. However, when endotoxemia and vasoconstrictor-masked hypovolemia work in concert in the pathogenesis of shock, the clinical scenario is more adverse compared to one of the insults acting alone. Matrix metalloproteinases (MMPs) are involved in chronic and acute heart failure by degrading the mechanical scaffold of the heart and several intracellular proteins. Therefore, the roles of MMP-2, MMP-9, MT1-MMP, focal adhesion kinase (FAK), and Paxillin in hearts of early multiple organ failure induced by norfenefrine-masked hypovolemia and endotoxemia were investigated in an ovine model. Experimental groups included (1) norfenefrine-masked hypovolemia plus endotoxemia (NMH+ENDO) (n=6), (2) norfenefrine-masked hypovolemia without endotoxemia (NMH) (n=6), (3) recurrent endotoxemia during normovolemia (ENDO) (n=6), and (4) healthy untreated controls (CON) (n=3). Apoptosis was determined by TUNEL-staining. Gel zymography revealed significantly increased MMP-2 activity in NMH+ENDO compared to ENDO and controls. MMP-9 activity was significantly elevated in all experimental groups. MMP-2 was significantly increased at the protein level, while MMP-9 was unaltered. MT1-MMP was not significantly changed in any group. Increased MMP activities were associated with cardiac deterioration. MMP-2/-9 activity and phosphorylated Paxillin (p-Paxillin) expression correlated positively with cardiomyocyte apoptosis. This study underscores the pivotal roles of MMP in acute cardiac dysfunction during early multiple organ failure in combined vasoconstrictor-masked hypovolemic and endotoxemia shock.
Collapse
|
32
|
Carlin SM, Resink TJ, Tamm M, Roth M. Urokinase signal transduction and its role in cell migration. FASEB J 2005; 19:195-202. [PMID: 15677342 DOI: 10.1096/fj.04-1644com] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Urokinase and its receptor uPAR play a role in cell migration that is being actively characterized. We previously reported that urokinase potentiates cell migration in human airway smooth muscle cells only where there is some primary migratory stimulus such as PDGF or recent exposure to growth medium. In this study, we examined the signaling of urokinase through its receptor, which lacks an intracellular domain and is presumed to act through associations with other membrane proteins. Whereas PDGF (30 min) and PDGF with urokinase increased the amount of the tyrosine dephosphorylase SHP2 in the membrane fraction, urokinase alone (30 min) decreased membrane SHP2. Analysis of the time course of urokinase stimulation showed that SHP2 was brought into association with the urokinase receptor uPAR between 2.5 and 20 min of urokinase, and later dissociated from it. Focal adhesion kinase was steadily lost from association with uPAR during urokinase stimulation, but its phosphorylation state increased and it became cleaved to smaller molecules. Association of uPAR with caveolin also decreased during urokinase stimulation. In contrast, the tyrosine kinase Src increased in the membrane fraction in response to urokinase stimulation. Disruption of raft structures by cyclodextrin treatment led to potentiation of PDGF chemotaxis, similar to urokinase action. Blocking of dephosphorylase activity with vanadate reduced basal cell migration and blocked the action of urokinase on PDGF chemotaxis. These observations support a role for urokinase in altering the phosphorylation state of focal adhesions, leading to breakdown of their structure and facilitation of cell motility.-Carlin, S. M., Resink, T. J., Tamm, M., Roth, M. Urokinase signal transduction and its role in cell migration.
Collapse
Affiliation(s)
- Stephen M Carlin
- Pulmonary Cell Research, Department of Research, University Hospital Basel, Basel, Switzerland
| | | | | | | |
Collapse
|
33
|
Yamashita M, Kamitani W, Yanai H, Ohtaki N, Watanabe Y, Lee BJ, Tsuji S, Ikuta K, Tomonaga K. Persistent borna disease virus infection confers instability of HSP70 mRNA in glial cells during heat stress. J Virol 2005; 79:2033-41. [PMID: 15681405 PMCID: PMC546570 DOI: 10.1128/jvi.79.4.2033-2041.2005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Borna disease virus (BDV) is a highly neurotropic RNA virus that causes neurological disorders in many vertebrate species. Although BDV readily establishes lasting persistence, persistently infected cells maintain an apparently normal cell phenotype in terms of morphology, viability, and proliferation. In this study, to understand the regulation of stress responses in BDV infection, we investigated the expression of heat shock proteins (HSPs) in glial cells persistently infected with BDV. Interestingly, we found that BDV persistence did not upregulate HSP70 expression even in cells treated with heat stress. Furthermore, BDV-infected glial cells exhibited rapid rounding and detachment from the culture plate under various stressful conditions. Immunofluorescence analysis demonstrated that heat stress rapidly disrupts the cell cytoskeleton only in persistently infected cells, suggesting a lack of thermotolerance. Intriguingly, we found that although persistently infected glial cells expressed HSP70 mRNA after heat stress, its expression rapidly disappeared during the recovery period. These observations indicated that persistent BDV infection may affect the stability of HSP70 mRNA. Finally, we found that the double-stranded RNA-dependent protein kinase (PKR) is expressed at a constant level in persistently infected cells with or without heat shock. Considering the interrelationship between HSP70 and PKR production, our data suggest that BDV infection disturbs the cellular stress responses to abolish antiviral activities and maintain persistence.
Collapse
Affiliation(s)
- Makiko Yamashita
- Department of Virology, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamadaoka, Suita Osaka 565-0871, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
34
|
Abstract
HSP60 has primarily been known as a mitochondrial protein that is important for folding key proteins after import into the mitochondria. It is now clear that a significant amount of HSP60 is also present in the extra-mitochondrial cytosol of many cells. In the heart, this cytosolic HSP60 complexes with Bax, Bak and Bcl-XL, but not with Bcl-2. Reduction in HSP60 expression precipitates apoptosis, but does not alter mitochondrial function. During hypoxia, HSP60 cellular distribution changes, with HSP60 leaving the cytosol, and translocating to the plasma membrane. Total cellular HSP60 does not change until 10 h of reoxygenation; however, release of cytochrome c from the mitochondria occurs prior to reoxygenation, coinciding with the redistribution of HSP60. The changes in HSP60, Bax and cytochrome c during hypoxia can be replicated by ATP depletion. HSP60 has also been shown to accelerate the cleavage of pro-caspase3. Thus, HSP60 has a complex role in apoptosis in the cell. Its binding to Bax under normal conditions suggests a key regulatory role in apoptosis.
Collapse
Affiliation(s)
- S. Gupta
- Molecular and Cellular Cardiology, Department of Medicine, University of California, Davis, CA and VA Medical Center, Sacramento, CA, USA
| | - A. A. Knowlton
- Molecular and Cellular Cardiology, Department of Medicine, University of California, Davis, CA and VA Medical Center, Sacramento, CA, USA
| |
Collapse
|
35
|
Beere HM. "The stress of dying": the role of heat shock proteins in the regulation of apoptosis. J Cell Sci 2005; 117:2641-51. [PMID: 15169835 DOI: 10.1242/jcs.01284] [Citation(s) in RCA: 455] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Heat shock proteins (Hsps) are a family of highly homologous chaperone proteins that are induced in response to environmental, physical and chemical stresses and that limit the consequences of damage and facilitate cellular recovery. The underlying ability of Hsps to maintain cell survival correlates with an inhibition of caspase activation and apoptosis that can, but does not always, depend upon their chaperoning activities. Several mechanisms proposed to account for these observations impact on both the "intrinsic", mitochondria-dependent and the "extrinsic", death-receptor-mediated pathways to apoptosis. Hsps can inhibit the activity of pro-apoptotic Bcl-2 proteins to prevent permeabilization of the outer mitochondrial membrane and release of apoptogenic factors. The disruption of apoptosome formation represents another mechanism by which Hsps can prevent caspase activation and induction of apoptosis. Several signaling cascades involved in the regulation of key elements within the apoptotic cascade are also subject to modulation by Hsps, including those involving JNK, NF-kappaB and AKT. The coordinated activities of the Hsps thus modulate multiple events within apoptotic pathways to help sustain cell survival following damaging stimuli.
Collapse
Affiliation(s)
- Helen M Beere
- La Jolla Institute for Allergy and Immunology, 10355 Science Center Drive, San Diego, CA 92121, USA.
| |
Collapse
|
36
|
Fleshner M, Campisi J, Amiri L, Diamond DM. Cat exposure induces both intra- and extracellular Hsp72: the role of adrenal hormones. Psychoneuroendocrinology 2004; 29:1142-52. [PMID: 15219638 DOI: 10.1016/j.psyneuen.2004.01.007] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2002] [Revised: 01/19/2004] [Accepted: 01/26/2004] [Indexed: 11/18/2022]
Abstract
Heat-shock proteins (Hsp) play an important role in stress physiology. Exposure to a variety of stressors will induce intracellular Hsp72, and this induction is believed to be beneficial for cell survival. In contrast, Hsp72 released during stress (extracellular Hsp72; eHsp72) activates pro-inflammatory responses. Clearly, physical stressors such as heat, cold, H(2)O(2), intense exercise and tail shock will induce both intra- and extracellular Hsp72. The current study tested whether a psychological stressor, cat exposure, would also trigger this response. In addition, the potential role of adrenal hormones in the Hsp72 response was examined. Adult, male Sprague Dawley rats were either adrenalectomized (ADX) or sham operated. Ten days post-recovery, rats were exposed to either a cat with no physical contact or control procedures (n = 5-6/group) for 2 h. Levels of intracellular Hsp72 were measured in the brain (frontal cortex, hippocampus, hypothalamus, dorsal vagal complex) and pituitary (ELISA). Levels of eHsp72 (ELISA) and corticosterone (RIA) were measured from serum obtained at the end of the 2-h stress period. Rats that were exposed to a cat had elevated intracellular Hsp72 in hypothalamus and dorsal vagal complex, and elevated eHsp72 and corticosterone in serum. Both the intra- and extracellular Hsp72 responses were blocked or attenuated by ADX. This study demonstrates that cat exposure can stimulate the Hsp72 response and that adrenal hormones contribute to this response.
Collapse
Affiliation(s)
- Monika Fleshner
- Department of Integrative Physiology, University of Colorado--Boulder, Boulder, CO 80309, USA.
| | | | | | | |
Collapse
|
37
|
Abstract
Protein-damaging stresses induce the expression of 'heat-shock proteins', which have essential roles in protecting cells from the potentially lethal effects of stress and proteotoxicity. These stress-protective heat-shock proteins are often overexpressed in cells of various cancers and have been suggested to be contributing factors in tumorigenesis. An underlying basis of oncogenesis is the acquisition and accumulation of mutations that provide the transformed cell with the combined characteristics of deregulated cell proliferation and suppressed cell death. Heat-shock proteins with dual roles as regulators of protein conformation and stress sensors may therefore have intriguing and central roles in both cell proliferation and apoptosis. It has been established that heat-shock proteins exhibit specificity to particular classes of polypeptide substrates and client proteins in vivo, and that chaperones can stabilize mutations that affect the folded conformation. Likewise, overexpression of chaperones has also been shown to protect cells against apoptotic cell death. The involvement of chaperones, therefore, in such diverse roles might suggest novel anticancer therapeutic approaches targeting heat-shock protein function for a broad spectrum of tumor types.
Collapse
Affiliation(s)
- Dick D Mosser
- Department of Molecular Biology and Genetics, University of Guelph, Guelph, Ontario, Canada N1G 2W1.
| | | |
Collapse
|
38
|
Mao H, Wang Y, Li Z, Ruchalski KL, Yu X, Schwartz JH, Borkan SC. Hsp72 interacts with paxillin and facilitates the reassembly of focal adhesions during recovery from ATP depletion. J Biol Chem 2004; 279:15472-80. [PMID: 14718530 DOI: 10.1074/jbc.m313484200] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The cytoprotective effect of heat stress proteins on epithelial cell detachment, an important cause of acute, ischemic renal failure, was examined after ATP depletion by evaluating focal adhesion complex (FAC) integrity. The intracellular distribution of FAC proteins (paxillin, talin, and vinculin) was assessed by immunohistochemistry before, during, and after exposure of renal epithelial cells to metabolic inhibitors. The resulting ATP depletion caused reversible re-distribution of all three proteins from focal adhesions to the cytosol. Paxillin, a key adaptor protein, was selected as a surrogate marker for FAC integrity in subsequent studies. Prior heat stress increased hsp72, a molecular chaperone, in both the Triton X-100-soluble and -insoluble protein fractions. Compared with ATP depleted control, heat stress significantly decreased paxillin and hsp72 shift from the Triton X-100 soluble to the insoluble protein fraction (an established marker of denaturation and aggregation); increased paxillin-hsp72 interaction detected by co-immunoprecipitation; enhanced paxillin extractability from Triton X-100-insoluble precipitates, increased the reformation of focal adhesions, and improved cell attachment (p < 0.05). To determine whether hsp72 mediates protection afforded by heat stress, cells were infected with adenovirus containing human hsp72 or empty vector. Hsp72 overexpression increased its interaction with paxillin and improved focal adhesion reformation during recovery, mimicking the protective effects of heat stress. These data suggest that hsp72 facilitates the reassembly of focal adhesions and improves cell attachment by reducing paxillin denaturation and increasing its re-solubilization after ATP depletion.
Collapse
Affiliation(s)
- Haiping Mao
- Department of Nephrology, First Affiliated Hospital, Zhongshan University, GuangZhou, China 510080
| | | | | | | | | | | | | |
Collapse
|