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Zhao K, Zhou G, Liu Y, Zhang J, Chen Y, Liu L, Zhang G. HSP70 Family in Cancer: Signaling Mechanisms and Therapeutic Advances. Biomolecules 2023; 13:601. [PMID: 37189349 PMCID: PMC10136146 DOI: 10.3390/biom13040601] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 03/10/2023] [Accepted: 03/17/2023] [Indexed: 03/29/2023] Open
Abstract
The 70 kDa heat shock proteins (HSP70s) are a group of highly conserved and inducible heat shock proteins. One of the main functions of HSP70s is to act as molecular chaperones that are involved in a large variety of cellular protein folding and remodeling processes. HSP70s are found to be over-expressed and may serve as prognostic markers in many types of cancers. HSP70s are also involved in most of the molecular processes of cancer hallmarks as well as the growth and survival of cancer cells. In fact, many effects of HSP70s on cancer cells are not only related to their chaperone activities but rather to their roles in regulating cancer cell signaling. Therefore, a number of drugs directly or indirectly targeting HSP70s, and their co-chaperones have been developed aiming to treat cancer. In this review, we summarized HSP70-related cancer signaling pathways and corresponding key proteins regulated by the family of HSP70s. In addition, we also summarized various treatment approaches and progress of anti-tumor therapy based on targeting HSP70 family proteins.
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Affiliation(s)
- Kejia Zhao
- Department of Thoracic Surgery and Institute of Thoracic Oncology, West China Hospital, Sichuan University, Chengdu 610041, China
- Western China Collaborative Innovation Center for Early Diagnosis and Multidisciplinary Therapy of Lung Cancer, Chengdu 610041, China
| | - Guanyu Zhou
- Department of Thoracic Surgery and Institute of Thoracic Oncology, West China Hospital, Sichuan University, Chengdu 610041, China
- Western China Collaborative Innovation Center for Early Diagnosis and Multidisciplinary Therapy of Lung Cancer, Chengdu 610041, China
- Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Yu Liu
- Faculty of Dentistry, The University of Hong Kong, Prince Philip Dental Hospital, Hong Kong 999077, China
| | - Jian Zhang
- Department of Thoracic Surgery and Institute of Thoracic Oncology, West China Hospital, Sichuan University, Chengdu 610041, China
- Western China Collaborative Innovation Center for Early Diagnosis and Multidisciplinary Therapy of Lung Cancer, Chengdu 610041, China
| | - Yaohui Chen
- Department of Thoracic Surgery and Institute of Thoracic Oncology, West China Hospital, Sichuan University, Chengdu 610041, China
- Western China Collaborative Innovation Center for Early Diagnosis and Multidisciplinary Therapy of Lung Cancer, Chengdu 610041, China
| | - Lunxu Liu
- Department of Thoracic Surgery and Institute of Thoracic Oncology, West China Hospital, Sichuan University, Chengdu 610041, China
- Western China Collaborative Innovation Center for Early Diagnosis and Multidisciplinary Therapy of Lung Cancer, Chengdu 610041, China
| | - Gao Zhang
- Faculty of Dentistry, The University of Hong Kong, Prince Philip Dental Hospital, Hong Kong 999077, China
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Xia L, Wang Z, Wu X, Zeng T, Luo W, Hu X, Ni Y, Che G, Liu L, Zhang W, Xie D, Li W. Multiplatform discovery and regulatory function analysis of structural variations in non-small cell lung carcinoma. Cell Rep 2021; 36:109660. [PMID: 34496260 DOI: 10.1016/j.celrep.2021.109660] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 06/06/2021] [Accepted: 08/11/2021] [Indexed: 02/08/2023] Open
Abstract
Non-small cell lung carcinoma (NSCLC), the most common form of lung cancer, is the leading cause of cancer-related death worldwide. We perform whole-genome sequencing (WGS) on samples from 43 primary patients with NSCLC and matched normal samples and analyze their matched open chromatin data and transcriptome data. Our results indicate that next-generation sequencing (NGS) and the Bionano Genomics (BNG) platform should be viewed as complementary technologies in terms of structural variations detection. By creating a framework integrating these two platforms, we detect high-technical-confidence somatic structural variations (SVs) in NSCLC cases, which could aid in the efficient investigation of new candidate oncogenes, such as TRIO and SESTD1. Our findings highlight the impact of somatic SVs on NSCLC oncogenesis and lay a foundation for exploring associations among somatic SVs, gene expression, and regulatory networks in patients with NSCLC.
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Affiliation(s)
- Lin Xia
- Frontier Science Center for Disease Molecular Network, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, No. 17 People's South Road, Chengdu, Sichuan 610041, China
| | - Zhoufeng Wang
- Frontier Science Center for Disease Molecular Network, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, No. 17 People's South Road, Chengdu, Sichuan 610041, China; Precision Medicine Research Center, West China Hospital, Sichuan University, No. 37 Guoxue Alley, Chengdu, Sichuan 610041, China; The Research Units of West China, Chinese Academy of Medical Sciences, West China Hospital, No. 37 Guoxue Alley, Chengdu, Sichuan 610041, China
| | - Xinyue Wu
- Frontier Science Center for Disease Molecular Network, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, No. 17 People's South Road, Chengdu, Sichuan 610041, China
| | - Tianfu Zeng
- Frontier Science Center for Disease Molecular Network, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, No. 17 People's South Road, Chengdu, Sichuan 610041, China
| | - Wenxin Luo
- Department of Respiratory and Critical Care Medicine, West China Hospital, Sichuan University, No. 37 Guoxue Alley, Chengdu, Sichuan 610041, China
| | - Xinlei Hu
- Frontier Science Center for Disease Molecular Network, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, No. 17 People's South Road, Chengdu, Sichuan 610041, China
| | - Yinyun Ni
- Precision Medicine Research Center, West China Hospital, Sichuan University, No. 37 Guoxue Alley, Chengdu, Sichuan 610041, China
| | - Guowei Che
- Department of Thoracic Surgery, West China Hospital, Sichuan University, No. 37 Guoxue Alley, Chengdu, Sichuan 610041, China
| | - Lunxu Liu
- Department of Thoracic Surgery, West China Hospital, Sichuan University, No. 37 Guoxue Alley, Chengdu, Sichuan 610041, China
| | - Wei Zhang
- Department of Respiratory and Critical Care Medicine, Shanghai Changhai Hospital, the Second Military Medical University, No. 168 Changhai Road, Shanghai 200433, China
| | - Dan Xie
- Frontier Science Center for Disease Molecular Network, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, No. 17 People's South Road, Chengdu, Sichuan 610041, China; Precision Medicine Research Center, West China Hospital, Sichuan University, No. 37 Guoxue Alley, Chengdu, Sichuan 610041, China.
| | - Weimin Li
- Frontier Science Center for Disease Molecular Network, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, No. 17 People's South Road, Chengdu, Sichuan 610041, China; Precision Medicine Research Center, West China Hospital, Sichuan University, No. 37 Guoxue Alley, Chengdu, Sichuan 610041, China; Department of Respiratory and Critical Care Medicine, West China Hospital, Sichuan University, No. 37 Guoxue Alley, Chengdu, Sichuan 610041, China; The Research Units of West China, Chinese Academy of Medical Sciences, West China Hospital, No. 37 Guoxue Alley, Chengdu, Sichuan 610041, China.
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Zempleni J, Liu D, Camara DT, Cordonier EL. Novel roles of holocarboxylase synthetase in gene regulation and intermediary metabolism. Nutr Rev 2014; 72:369-76. [PMID: 24684412 DOI: 10.1111/nure.12103] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The role of holocarboxylase synthetase (HLCS) in catalyzing the covalent binding of biotin to the five biotin-dependent carboxylases in humans is well established, as are the essential roles of these carboxylases in the metabolism of fatty acids, the catabolism of leucine, and gluconeogenesis. This review examines recent discoveries regarding the roles of HLCS in assembling a multiprotein gene repression complex in chromatin. In addition, emerging evidence suggests that the number of biotinylated proteins is far larger than previously assumed and includes members of the heat-shock superfamily of proteins and proteins coded by the ENO1 gene. Evidence is presented linking biotinylation of heat-shock proteins HSP60 and HSP72 with redox biology and immune function, respectively, and biotinylation of the two ENO1 gene products MBP-1 and ENO1 with tumor suppression and glycolysis, respectively.
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Affiliation(s)
- Janos Zempleni
- Department of Nutrition and Health Sciences, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
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Xue J, Zhou J, Zempleni J. Holocarboxylase synthetase catalyzes biotinylation of heat shock protein 72, thereby inducing RANTES expression in HEK-293 cells. Am J Physiol Cell Physiol 2013; 305:C1240-5. [PMID: 24133061 DOI: 10.1152/ajpcell.00279.2013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In a recent mass spectrometry screen, we identified 108 new proteins that were modified endogenously by covalent binding of biotin; members of the heat shock superfamily of proteins, including heat shock protein 72 (HSP72), were overrepresented among the biotinylated proteins. Mammals respond to infections by secreting extracellular HSP72 (eHSP72), which elicits an immune response. Here, using mass spectrometry and site-directed mutagenesis, we identified five biotinylation sites in HSP72. We used coimmunoprecipitation, mass spectrometry, and limited proteolysis assays to demonstrate that HSP72 interacts physically with the protein biotin ligase holocarboxylase synthetase (HLCS), leading to biotinylation of residues K112, K128 K348, K361, K415, and, probably, additional lysines. Finally, we demonstrated that HLCS-dependent biotinylation of eHSP72 increases expression of the chemokine regulated on activation normal T-expressed and presumably secreted (RANTES) by human embryonic kidney (HEK-293) cells. In conclusion, we report a novel endogenous modification of HSP72 and demonstrated that binding of biotin to eHSP72 prepares cells for a strong immune response.
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Affiliation(s)
- Jing Xue
- Department of Nutrition and Health Sciences, University of Nebraska at Lincoln, Lincoln, Nebraska
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May LA, Kramarenko II, Brandon CS, Voelkel-Johnson C, Roy S, Truong K, Francis SP, Monzack EL, Lee FS, Cunningham LL. Inner ear supporting cells protect hair cells by secreting HSP70. J Clin Invest 2013; 123:3577-87. [PMID: 23863716 DOI: 10.1172/jci68480] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Accepted: 05/03/2013] [Indexed: 02/02/2023] Open
Abstract
Mechanosensory hair cells are the receptor cells of hearing and balance. Hair cells are sensitive to death from exposure to therapeutic drugs with ototoxic side effects, including aminoglycoside antibiotics and cisplatin. We recently showed that the induction of heat shock protein 70 (HSP70) inhibits ototoxic drug-induced hair cell death. Here, we examined the mechanisms underlying the protective effect of HSP70. In response to heat shock, HSP70 was induced in glia-like supporting cells but not in hair cells. Adenovirus-mediated infection of supporting cells with Hsp70 inhibited hair cell death. Coculture with heat-shocked utricles protected nonheat-shocked utricles against hair cell death. When heat-shocked utricles from Hsp70-/- mice were used in cocultures, protection was abolished in both the heat-shocked utricles and the nonheat-shocked utricles. HSP70 was detected by ELISA in the media surrounding heat-shocked utricles, and depletion of HSP70 from the media abolished the protective effect of heat shock, suggesting that HSP70 is secreted by supporting cells. Together our data indicate that supporting cells mediate the protective effect of HSP70 against hair cell death, and they suggest a major role for supporting cells in determining the fate of hair cells exposed to stress.
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Affiliation(s)
- Lindsey A May
- National Institute on Deafness and Other Communication Disorders, NIH, Rockville, Maryland 20850, USA
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Jakobsohn K, Motiei M, Sinvani M, Popovtzer R. Towards real-time detection of tumor margins using photothermal imaging of immune-targeted gold nanoparticles. Int J Nanomedicine 2012; 7:4707-13. [PMID: 22956871 PMCID: PMC3431967 DOI: 10.2147/ijn.s34157] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND One of the critical problems in cancer management is local recurrence of disease. Between 20% and 30% of patients who undergo tumor resection surgery require reoperation due to incomplete excision. Currently, there are no validated methods for intraoperative tumor margin detection. In the present work, we demonstrate the potential use of gold nanoparticles (GNPs) as a novel contrast agent for photothermal molecular imaging of cancer. METHODS Phantoms containing different concentrations of GNPs were irradiated with continuous-wave laser and measured with a thermal imaging camera which detected the temperature field of the irradiated phantoms. RESULTS The results clearly demonstrate the ability to distinguish between cancerous cells specifically targeted with GNPs and normal cells. This technique, which allows highly sensitive discrimination between adjacent low GNP concentrations, will allow tumor margin detection while the temperature increases by only a few degrees Celsius (for GNPs in relevant biological concentrations). CONCLUSION We expect this real-time intraoperative imaging technique to assist surgeons in determining clear tumor margins and to maximize the extent of tumor resection while sparing normal background tissue.
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Affiliation(s)
- Kobi Jakobsohn
- Faculty of Engineering, Institute of Nanotechnology and Advanced Materials, Bar Ilan University, Ramat Gan, Israel
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Henderson B, Pockley AG. Proteotoxic stress and circulating cell stress proteins in the cardiovascular diseases. Cell Stress Chaperones 2012; 17:303-11. [PMID: 22215517 PMCID: PMC3312955 DOI: 10.1007/s12192-011-0318-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2011] [Revised: 12/15/2011] [Accepted: 12/16/2011] [Indexed: 12/28/2022] Open
Abstract
The cardiovasculature is one of the major body systems and probably the one most exposed to stress. There is clear evidence that increasing levels of cell stress proteins within the heart is cardioprotective. In addition, there is rapidly emerging evidence that secreted cell stress proteins play a role in the function of the cardiovascular tissues. Those secreted proteins have three potential functions: (1) as normal homeostatic cardiovascular signals (e.g. protein disulphide isomerase); (2) as anti-inflammatory molecules, which are able to inhibit cardiovascular pathology (e.g. Hsp27); and (iii) as pro-inflammatory signals that can induce and promote cardiovascular pathology (e.g. Hsp60). As all of these various proteins may be released-at different rates-and in different cardiovascular diseases-we need to consider the cohort of potential secreted cell stress proteins as a dynamic system (network) that can aid and/or damage the equally dynamic cardiovascular system.
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Affiliation(s)
- Brian Henderson
- Department of Microbial Diseases, UCL-Eastman Dental Institute, University College London, London, UK.
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Wolf F, Li W, Li F, Li CY. Non-invasive, quantitative monitoring of hyperthermia-induced EGFR activation in xenograft tumours. Int J Hyperthermia 2011; 27:427-34. [PMID: 21756040 DOI: 10.3109/02656736.2011.566593] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
PURPOSE To examine the molecular mechanism of cellular EGFR activation during hyperthermia treatment. MATERIALS AND METHODS EGR activities in tumour cells were quantified through the use of a recently developed split-luciferase-based EGFR reporter system which allowed us to monitor EGFR activation in vitro as well as in vivo in a non-invasive manner. RESULTS We found that hyperthermia treatment of MDA-MB231 breast cancer cells resulted in a strong induction of EGFR activity in tissue culture as well as in xenograft tumours. Furthermore, we found that this induction is mediated by the heat shock protein Hsp90. Administration of the specific Hsp90 inhibitor geldanamycin as well as RNAi directed against HSP90 effectively inhibited EGFR activation, suggesting an essential role for Hsp90 in hyperthermia-induced EGFR activation. In addition, cells treated with geldanamycin were sensitised to heat treatment, suggesting that adding Hsp90 inhibitors to hyperthermia regimens might have a beneficial effect for cancer treatment. CONCLUSIONS Our bioluminescent imaging reporter provided a powerful tool to examine hyperthermia-induced EGFR activation in vitro as well as in vivo. Hsp90 was found to be a key factor mediating heat-induced EGFR activation in tumour cells.
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Affiliation(s)
- Frank Wolf
- Department of Radiation Oncology, University of Colorado School of Medicine, Aurorao, CO 80010, USA
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Yashin DV, Dukhanina EA, Kabanova OD, Romanova EA, Lukyanova TI, Tonevitskii AG, Belogurov AA, Raynes DA, Sheludchenkov AA, Gnuchev NV, Guerriero V, Georgiev GP, Sashchenko LP. Extracellular HspBP1 inhibits formation of a cytotoxic Tag7-Hsp70 complex in vitro and in human serum. Biochimie 2011; 94:203-6. [PMID: 22037021 DOI: 10.1016/j.biochi.2011.10.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2011] [Accepted: 10/13/2011] [Indexed: 10/16/2022]
Abstract
Tag7 (PGRP-S) was described as an innate immunity protein. Earlier we have shown that Tag7 forms with Hsp70 a stable complex with cytotoxic and antitumor activity. The same complex is formed in and secreted by cytotoxic T-lymphocytes. We have also found that Hsp-binding protein HspBP1 incapacitates the Tag7-Hsp70 complex. Here we have studied the interaction of extracellular Tag7 and HspBP1. We have shown that HspBP1 binds Tag7 in the conditioned medium of tumor CSML0 cells, thereby preventing formation of the cytotoxic Tag7-Hsp70 complex. We have also found that Tag7, if present in serum (in every third donor on average), is always in complex with HspBP1. This may be a protective measure against indiscriminate attack of the cytotoxic complex on normal cells.
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Affiliation(s)
- Denis V Yashin
- Institute of Gene Biology, Russian Academy of Sciences (RAS), Moscow 119344, Russia
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Yashin DV, Dukhanina EA, Kabanova OD, Romanova EA, Lukyanova TI, Tonevitskii AG, Raynes DA, Gnuchev NV, Guerriero V, Georgiev GP, Sashchenko LP. The heat shock-binding protein (HspBP1) protects cells against the cytotoxic action of the Tag7-Hsp70 complex. J Biol Chem 2011; 286:10258-64. [PMID: 21247889 PMCID: PMC3060480 DOI: 10.1074/jbc.m110.163436] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2010] [Revised: 12/22/2010] [Indexed: 01/02/2023] Open
Abstract
Heat shock-binding protein HspBP1 is a member of the Hsp70 co-chaperone family. The interaction between HspBP1 and the ATPase domain of the major heat shock protein Hsp70 up-regulates nucleotide exchange and reduces the affinity between Hsp70 and the peptide in its peptide-binding site. Previously we have shown that Tag7 (also known as peptidoglycan recognition protein PGRP-S), an innate immunity protein, interacts with Hsp70 to form a stable Tag7-Hsp70 complex with cytotoxic activity against some tumor cell lines. This complex can be produced in cytotoxic lymphocytes and released during interaction with tumor cells. Here the effect of HspBP1 on the cytotoxic activity of the Tag7-Hsp70 complex was examined. HspBP1 could bind not only to Hsp70, but also to Tag7. This interaction eliminated the cytotoxic activity of Tag7-Hsp70 complex and decreased the ATP concentration required to dissociate Tag7 from the peptide-binding site of Hsp70. Moreover, HspBP1 inhibited the cytotoxic activity of the Tag7-Hsp70 complex secreted by lymphocytes. HspBP1 was detected in cytotoxic CD8+ lymphocytes. This protein was released simultaneously with Tag7-Hsp70 during interaction of these lymphocytes with tumor cells. The simultaneous secretion of the cytotoxic complex with its inhibitor could be a mechanism protecting normal cells from the cytotoxic effect of this complex.
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Affiliation(s)
- Denis V. Yashin
- From the Institute of Gene Biology and
- the Centre for Medical Studies, University of Oslo, Moscow 119344, Russia
| | - Elena A. Dukhanina
- From the Institute of Gene Biology and
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences (RAS), Moscow 119344, Russia
| | | | | | | | | | | | | | - Vince Guerriero
- the Department of Animal Sciences and
- Department of Molecular and Cellular Biology, University of Arizona, Tucson, Arizona 85721, and
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Graner MW, Raynes DA, Bigner DD, Guerriero V. Heat shock protein 70-binding protein 1 is highly expressed in high-grade gliomas, interacts with multiple heat shock protein 70 family members, and specifically binds brain tumor cell surfaces. Cancer Sci 2009; 100:1870-9. [PMID: 19659607 DOI: 10.1111/j.1349-7006.2009.01269.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Chaperone proteins and heat shock proteins (HSP) are essential components of cellular protein folding systems under normal conditions; their expression and activities are upregulated during stress. Chronically stressed tumors frequently exhibit high chaperone protein levels, exploiting their anti-apoptotic mechanisms and general proteome homeostasis amidst a background of genetic instability. Co-chaperones interact with chaperones as malleable regulatory components of protein folding activity and may represent a conduit for modification of chaperone activity to the detriment of the tumor. We have initially characterized one such co-chaperone, heat shock protein 70-binding protein (HspBP) 1 from human brain tumors, their xenografts grown in immune-compromised mice, and in syngeneic murine models in immune-competent mice. Immunohistochemical analyses show HspBP1 overexpression (with unusual subcellular localizations) in patient brain tumors relative to normal brain tissue. This holds true for the xenograft and syngeneic murine tumor models. In biochemical affinity chromatography assays, HspBP1 interacts with members of the HSP70 family from brain tumor lysates and from surface-derived samples, including HSP70, glucose regulated protein (GRP)75, GRP78, and HSP110. From normal brain lysates, only heat shock cognate (HSC)70, GRP75, and HSP110 bind to HspBP1. FACS analyses indicate that HspBP1 binds to brain tumor cell surfaces, possibly via HSP70 family members, and internalizes into cells. This has implications for HspBP1 biology as well as its utility as a tumor-targeting agent. Our results suggest that HspBP1 may play a role in tumor (dys)regulation of chaperone proteins, and that HspBP1 may have extracellular roles with therapeutic implications.
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Affiliation(s)
- Michael W Graner
- Department of Pathology, and the Preston Robert Tisch Brain Tumor Center, Duke University Medical Center, Durham, NC, USA.
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