1
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Murphy CS, DeMambro VE, Fadel S, Fairfield H, Garter CA, Rodriguez P, Qiang YW, Vary CPH, Reagan MR. Inhibition of Acyl-CoA Synthetase Long Chain Isozymes Decreases Multiple Myeloma Cell Proliferation and Causes Mitochondrial Dysfunction. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.13.583708. [PMID: 38559245 PMCID: PMC10979990 DOI: 10.1101/2024.03.13.583708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Multiple myeloma (MM) is an incurable cancer of plasma cells with a 5-year survival rate of 59%. Dysregulation of fatty acid (FA) metabolism is associated with MM development and progression; however, the underlying mechanisms remain unclear. Acyl-CoA synthetase long-chain family members (ACSLs) convert free long-chain fatty acids into fatty acyl-CoA esters and play key roles in catabolic and anabolic fatty acid metabolism. The Cancer Dependency Map data suggested that ACSL3 and ACSL4 were among the top 25% Hallmark Fatty Acid Metabolism genes that support MM fitness. Here, we show that inhibition of ACSLs in human myeloma cell lines using the pharmacological inhibitor Triascin C (TriC) causes apoptosis and decreases proliferation in a dose- and time-dependent manner. RNA-seq of MM.1S cells treated with TriC for 24 h showed a significant enrichment in apoptosis, ferroptosis, and ER stress. Proteomics of MM.1S cells treated with TriC for 48 h revealed that mitochondrial dysfunction and oxidative phosphorylation were significantly enriched pathways of interest, consistent with our observations of decreased mitochondrial membrane potential and increased mitochondrial superoxide levels. Interestingly, MM.1S cells treated with TriC for 24 h also showed decreased mitochondrial ATP production rates and overall lower cellular respiration.
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Affiliation(s)
- Connor S Murphy
- Center for Molecular Medicine, MaineHealth Institute for Research, Scarborough, ME, USA
- University of Maine, University of Maine Graduate School of Biomedical Science and Engineering, Orono, ME, USA
| | - Victoria E DeMambro
- Center for Molecular Medicine, MaineHealth Institute for Research, Scarborough, ME, USA
- University of Maine, University of Maine Graduate School of Biomedical Science and Engineering, Orono, ME, USA
| | - Samaa Fadel
- Center for Molecular Medicine, MaineHealth Institute for Research, Scarborough, ME, USA
- University of New England, Biddeford, ME, USA
| | - Heather Fairfield
- Center for Molecular Medicine, MaineHealth Institute for Research, Scarborough, ME, USA
- University of Maine, University of Maine Graduate School of Biomedical Science and Engineering, Orono, ME, USA
- Tufts University School of Medicine, Boston MA, USA
| | - Carlos A Garter
- Center for Molecular Medicine, MaineHealth Institute for Research, Scarborough, ME, USA
- University of Maine, University of Maine Graduate School of Biomedical Science and Engineering, Orono, ME, USA
| | | | - Ya-Wei Qiang
- Center for Molecular Medicine, MaineHealth Institute for Research, Scarborough, ME, USA
| | - Calvin P H Vary
- Center for Molecular Medicine, MaineHealth Institute for Research, Scarborough, ME, USA
- University of Maine, University of Maine Graduate School of Biomedical Science and Engineering, Orono, ME, USA
- Tufts University School of Medicine, Boston MA, USA
| | - Michaela R Reagan
- Center for Molecular Medicine, MaineHealth Institute for Research, Scarborough, ME, USA
- University of Maine, University of Maine Graduate School of Biomedical Science and Engineering, Orono, ME, USA
- Tufts University School of Medicine, Boston MA, USA
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2
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Perea V, Baron KR, Dolina V, Aviles G, Kim G, Rosarda JD, Guo X, Kampmann M, Wiseman RL. Pharmacologic activation of a compensatory integrated stress response kinase promotes mitochondrial remodeling in PERK-deficient cells. Cell Chem Biol 2023; 30:1571-1584.e5. [PMID: 37922906 PMCID: PMC10842031 DOI: 10.1016/j.chembiol.2023.10.006] [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: 05/16/2023] [Revised: 08/21/2023] [Accepted: 10/10/2023] [Indexed: 11/07/2023]
Abstract
The integrated stress response (ISR) comprises the eIF2α kinases PERK, GCN2, HRI, and PKR, which induce translational and transcriptional signaling in response to diverse insults. Deficiencies in PERK signaling lead to mitochondrial dysfunction and contribute to the pathogenesis of numerous diseases. We define the potential for pharmacologic activation of compensatory eIF2α kinases to rescue ISR signaling and promote mitochondrial adaptation in PERK-deficient cells. We show that the HRI activator BtdCPU and GCN2 activator halofuginone promote ISR signaling and rescue ER stress sensitivity in PERK-deficient cells. However, BtdCPU induces mitochondrial depolarization, leading to mitochondrial fragmentation and activation of the OMA1-DELE1-HRI signaling axis. In contrast, halofuginone promotes mitochondrial elongation and adaptive mitochondrial respiration, mimicking regulation induced by PERK. This shows halofuginone can compensate for deficiencies in PERK signaling and promote adaptive mitochondrial remodeling, highlighting the potential for pharmacologic ISR activation to mitigate mitochondrial dysfunction and motivating the pursuit of highly selective ISR activators.
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Affiliation(s)
- Valerie Perea
- Department of Molecular and Cellular Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Kelsey R Baron
- Department of Molecular and Cellular Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Vivian Dolina
- Department of Molecular and Cellular Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Giovanni Aviles
- Department of Biophysics and Biochemistry and Institute for Neurodegenerative Diseases, UCSF, San Francisco, CA 94158, USA
| | - Grace Kim
- Department of Molecular and Cellular Biology, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Jessica D Rosarda
- Department of Molecular and Cellular Biology, The Scripps Research Institute, La Jolla, CA 92037, USA; Department of Anatomy, Physiology, and Genetics, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| | - Xiaoyan Guo
- Department of Biophysics and Biochemistry and Institute for Neurodegenerative Diseases, UCSF, San Francisco, CA 94158, USA; Department of Genetics and Genome Sciences, University of Connecticut Health, Farmington, CT 06030, USA
| | - Martin Kampmann
- Department of Biophysics and Biochemistry and Institute for Neurodegenerative Diseases, UCSF, San Francisco, CA 94158, USA
| | - R Luke Wiseman
- Department of Molecular and Cellular Biology, The Scripps Research Institute, La Jolla, CA 92037, USA.
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3
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Kalinin A, Zubkova E, Menshikov M. Integrated Stress Response (ISR) Pathway: Unraveling Its Role in Cellular Senescence. Int J Mol Sci 2023; 24:17423. [PMID: 38139251 PMCID: PMC10743681 DOI: 10.3390/ijms242417423] [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: 11/02/2023] [Revised: 12/11/2023] [Accepted: 12/12/2023] [Indexed: 12/24/2023] Open
Abstract
Cellular senescence is a complex process characterized by irreversible cell cycle arrest. Senescent cells accumulate with age, promoting disease development, yet the absence of specific markers hampers the development of selective anti-senescence drugs. The integrated stress response (ISR), an evolutionarily highly conserved signaling network activated in response to stress, globally downregulates protein translation while initiating the translation of specific protein sets including transcription factors. We propose that ISR signaling plays a central role in controlling senescence, given that senescence is considered a form of cellular stress. Exploring the intricate relationship between the ISR pathway and cellular senescence, we emphasize its potential as a regulatory mechanism in senescence and cellular metabolism. The ISR emerges as a master regulator of cellular metabolism during stress, activating autophagy and the mitochondrial unfolded protein response, crucial for maintaining mitochondrial quality and efficiency. Our review comprehensively examines ISR molecular mechanisms, focusing on ATF4-interacting partners, ISR modulators, and their impact on senescence-related conditions. By shedding light on the intricate relationship between ISR and cellular senescence, we aim to inspire future research directions and advance the development of targeted anti-senescence therapies based on ISR modulation.
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Affiliation(s)
- Alexander Kalinin
- National Medical Research Centre of Cardiology Named after Academician E.I. Chazov, 121552 Moscow, Russia; (A.K.); (E.Z.)
- Faculty of Fundamental Medicine, Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Ekaterina Zubkova
- National Medical Research Centre of Cardiology Named after Academician E.I. Chazov, 121552 Moscow, Russia; (A.K.); (E.Z.)
| | - Mikhail Menshikov
- National Medical Research Centre of Cardiology Named after Academician E.I. Chazov, 121552 Moscow, Russia; (A.K.); (E.Z.)
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4
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Perea V, Baron KR, Dolina V, Aviles G, Rosarda JD, Guo X, Kampmann M, Wiseman RL. Pharmacologic Activation of a Compensatory Integrated Stress Response Kinase Promotes Mitochondrial Remodeling in PERK-deficient Cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.11.532186. [PMID: 36945406 PMCID: PMC10029010 DOI: 10.1101/2023.03.11.532186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/13/2023]
Abstract
The integrated stress response (ISR) comprises the eIF2α kinases PERK, GCN2, HRI, and PKR, which induce translational and transcriptional signaling in response to diverse insults. Deficiencies in PERK signaling lead to mitochondrial dysfunction and contribute to the pathogenesis of numerous diseases. We define the potential for pharmacologic activation of compensatory eIF2α kinases to rescue ISR signaling and promote mitochondrial adaptation in PERK-deficient cells. We show that the HRI activator BtdCPU and GCN2 activator halofuginone promote ISR signaling and rescue ER stress sensitivity in PERK-deficient cells. However, BtdCPU induces mitochondrial depolarization, leading to mitochondrial fragmentation and activation of the OMA1-DELE1-HRI signaling axis. In contrast, halofuginone promotes mitochondrial elongation and adaptive mitochondrial respiration, mimicking regulation induced by PERK. This shows halofuginone can compensate for deficiencies in PERK signaling and promote adaptive mitochondrial remodeling, highlighting the potential for pharmacologic ISR activation to mitigate mitochondrial dysfunction and motivating the pursuit of highly-selective ISR activators.
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Affiliation(s)
- Valerie Perea
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA 92037
- Authors contributed equally
| | - Kelsey R. Baron
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA 92037
- Authors contributed equally
| | - Vivian Dolina
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA 92037
| | - Giovanni Aviles
- Department of Biophysics and Biochemistry and Institute for Neurodegenerative Diseases, UCSF, San Francisco, CA 94158
| | - Jessica D. Rosarda
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA 92037
| | - Xiaoyan Guo
- Department of Biophysics and Biochemistry and Institute for Neurodegenerative Diseases, UCSF, San Francisco, CA 94158
- Department of Genetics and Genome Sciences, University of Connecticut Health, Farmington, CT 06030
| | - Martin Kampmann
- Department of Biophysics and Biochemistry and Institute for Neurodegenerative Diseases, UCSF, San Francisco, CA 94158
| | - R. Luke Wiseman
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA 92037
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5
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Nwosu GO, Powell JA, Pitson SM. Targeting the integrated stress response in hematologic malignancies. Exp Hematol Oncol 2022; 11:94. [DOI: 10.1186/s40164-022-00348-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Accepted: 10/22/2022] [Indexed: 11/09/2022] Open
Abstract
AbstractWhile numerous targeted therapies have been recently adopted to improve the treatment of hematologic malignancies, acquired or intrinsic resistance poses a significant obstacle to their efficacy. Thus, there is increasing need to identify novel, targetable pathways to further improve therapy for these diseases. The integrated stress response is a signaling pathway activated in cancer cells in response to both dysregulated growth and metabolism, and also following exposure to many therapies that appears one such targetable pathway for improved treatment of these diseases. In this review, we discuss the role of the integrated stress response in the biology of hematologic malignancies, its critical involvement in the mechanism of action of targeted therapies, and as a target for pharmacologic modulation as a novel strategy for the treatment of hematologic malignancies.
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6
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Yerlikaya A. Heme-regulated inhibitor: an overlooked eIF2α kinase in cancer investigations. Med Oncol 2022; 39:73. [PMID: 35568791 DOI: 10.1007/s12032-022-01668-1] [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: 12/30/2021] [Accepted: 01/24/2022] [Indexed: 10/18/2022]
Abstract
Heme-regulated inhibitor (HRI) kinase is a serine-threonine kinase, controlling the initiation of protein synthesis via phosphorylating α subunit of eIF2 on serine 51 residue, mainly in response to heme deprivation in erythroid cells. However, recent studies showed that HRI is also activated by several diverse signals, causing dysregulations in intracellular homeostatic mechanisms in non-erythroid cells. For instance, it was reported that the decrease in protein synthesis upon the 26S proteasomal inhibition by MG132 or bortezomib is mediated by increased eIF2α phosphorylation in an HRI-dependent manner in mouse embryonic fibroblast cells. The increase in eIF2α phosphorylation level through the activation of HRI upon 26S proteasomal inhibition is believed to protect cells against the buildup of misfolded and ubiquitinated proteins, having the potential to trigger the apoptotic response. In contrast, prolonged and sustained HRI-mediated eIF2α phosphorylation can induce cell death, which may involve ATF4 and CHOP expression. Altogether, these studies suggest that HRI-mediated eIF2α phosphorylation may be cytoprotective or cytotoxic depending on the cells, type, and duration of pharmacological agents used. It is thus hypothesized that both HRI activators, inducing eIF2α phosphorylation or HRI inhibitors causing disturbances in eIF2α phosphorylation, may be effective as novel strategies in cancer treatment if the balance in eIF2α phosphorylation is shifted in favor of autophagic or apoptotic response in cancer cells. It is here aimed to review the role of HRI in various biological mechanisms as well as the therapeutic potentials of recently developed HRI activators and inhibitors, targeting eIF2α phosphorylation in cancer cells.
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Affiliation(s)
- Azmi Yerlikaya
- Department of Medical Biology, Faculty of Medicine, Kutahya Health Sciences University, Kutahya, Turkey.
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7
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Fabbri L, Chakraborty A, Robert C, Vagner S. The plasticity of mRNA translation during cancer progression and therapy resistance. Nat Rev Cancer 2021; 21:558-577. [PMID: 34341537 DOI: 10.1038/s41568-021-00380-y] [Citation(s) in RCA: 83] [Impact Index Per Article: 27.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/14/2021] [Indexed: 02/07/2023]
Abstract
Translational control of mRNAs during gene expression allows cells to promptly and dynamically adapt to a variety of stimuli, including in neoplasia in response to aberrant oncogenic signalling (for example, PI3K-AKT-mTOR, RAS-MAPK and MYC) and microenvironmental stress such as low oxygen and nutrient supply. Such translational rewiring allows rapid, specific changes in the cell proteome that shape specific cancer phenotypes to promote cancer onset, progression and resistance to anticancer therapies. In this Review, we illustrate the plasticity of mRNA translation. We first highlight the diverse mechanisms by which it is regulated, including by translation factors (for example, eukaryotic initiation factor 4F (eIF4F) and eIF2), RNA-binding proteins, tRNAs and ribosomal RNAs that are modulated in response to aberrant intracellular pathways or microenvironmental stress. We then describe how translational control can influence tumour behaviour by impacting on the phenotypic plasticity of cancer cells as well as on components of the tumour microenvironment. Finally, we highlight the role of mRNA translation in the cellular response to anticancer therapies and its promise as a key therapeutic target.
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Affiliation(s)
- Lucilla Fabbri
- Institut Curie, PSL Research University, CNRS UMR3348, INSERM U1278, Orsay, France
- Université Paris Sud, Université Paris-Saclay, CNRS UMR3348, INSERM U1278, Orsay, France
- Equipe Labellisée Ligue Nationale Contre le Cancer, Orsay, France
| | - Alina Chakraborty
- Institut Curie, PSL Research University, CNRS UMR3348, INSERM U1278, Orsay, France
- Université Paris Sud, Université Paris-Saclay, CNRS UMR3348, INSERM U1278, Orsay, France
- Equipe Labellisée Ligue Nationale Contre le Cancer, Orsay, France
| | - Caroline Robert
- INSERM U981, Gustave Roussy Cancer Campus, Villejuif, France
- Université Paris-Sud, Université Paris-Saclay, Kremlin-Bicêtre, France
- Dermato-Oncology, Gustave Roussy Cancer Campus, Villejuif, France
| | - Stéphan Vagner
- Institut Curie, PSL Research University, CNRS UMR3348, INSERM U1278, Orsay, France.
- Université Paris Sud, Université Paris-Saclay, CNRS UMR3348, INSERM U1278, Orsay, France.
- Equipe Labellisée Ligue Nationale Contre le Cancer, Orsay, France.
- Dermato-Oncology, Gustave Roussy Cancer Campus, Villejuif, France.
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8
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Xiong S, Chng WJ, Zhou J. Crosstalk between endoplasmic reticulum stress and oxidative stress: a dynamic duo in multiple myeloma. Cell Mol Life Sci 2021; 78:3883-3906. [PMID: 33599798 PMCID: PMC8106603 DOI: 10.1007/s00018-021-03756-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 12/19/2020] [Accepted: 01/05/2021] [Indexed: 02/07/2023]
Abstract
Under physiological and pathological conditions, cells activate the unfolded protein response (UPR) to deal with the accumulation of unfolded or misfolded proteins in the endoplasmic reticulum. Multiple myeloma (MM) is a hematological malignancy arising from immunoglobulin-secreting plasma cells. MM cells are subject to continual ER stress and highly dependent on the UPR signaling activation due to overproduction of paraproteins. Mounting evidence suggests the close linkage between ER stress and oxidative stress, demonstrated by overlapping signaling pathways and inter-organelle communication pivotal to cell fate decision. Imbalance of intracellular homeostasis can lead to deranged control of cellular functions and engage apoptosis due to mutual activation between ER stress and reactive oxygen species generation through a self-perpetuating cycle. Here, we present accumulating evidence showing the interactive roles of redox homeostasis and proteostasis in MM pathogenesis and drug resistance, which would be helpful in elucidating the still underdefined molecular pathways linking ER stress and oxidative stress in MM. Lastly, we highlight future research directions in the development of anti-myeloma therapy, focusing particularly on targeting redox signaling and ER stress responses.
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Affiliation(s)
- Sinan Xiong
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117597, Republic of Singapore
| | - Wee-Joo Chng
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117597, Republic of Singapore.
- Centre for Translational Medicine, Cancer Science Institute of Singapore, National University of Singapore, 14 Medical Drive, Singapore, 117599, Republic of Singapore.
- Department of Hematology-Oncology, National University Cancer Institute of Singapore (NCIS), The National University Health System (NUHS), 1E, Kent Ridge Road, Singapore, 119228, Republic of Singapore.
| | - Jianbiao Zhou
- Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117597, Republic of Singapore.
- Centre for Translational Medicine, Cancer Science Institute of Singapore, National University of Singapore, 14 Medical Drive, Singapore, 117599, Republic of Singapore.
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9
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Rahem SM, Epsi NJ, Coffman FD, Mitrofanova A. Genome-wide analysis of therapeutic response uncovers molecular pathways governing tamoxifen resistance in ER+ breast cancer. EBioMedicine 2020; 61:103047. [PMID: 33099086 PMCID: PMC7585053 DOI: 10.1016/j.ebiom.2020.103047] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 09/02/2020] [Accepted: 09/18/2020] [Indexed: 01/10/2023] Open
Abstract
Background Prioritization of breast cancer patients based on the risk of resistance to tamoxifen plays a significant role in personalized therapeutic planning and improving disease course and outcomes. Methods In this work, we demonstrate that a genome-wide pathway-centric computational framework elucidates molecular pathways as markers of tamoxifen resistance in ER+ breast cancer patients. In particular, we associated activity levels of molecular pathways with a wide spectrum of response to tamoxifen, which defined markers of tamoxifen resistance in patients with ER+ breast cancer. Findings We identified five biological pathways as markers of tamoxifen failure and demonstrated their ability to predict the risk of tamoxifen resistance in two independent patient cohorts (Test cohort1: log-rank p-value = 0.02, adjusted HR = 3.11; Test cohort2: log-rank p-value = 0.01, adjusted HR = 4.24). We have shown that these pathways are not markers of aggressiveness and outperform known markers of tamoxifen response. Furthermore, for adoption into clinic, we derived a list of pathway read-out genes and their associated scoring system, which assigns a risk of tamoxifen resistance for new incoming patients. Interpretation We propose that the identified pathways and their read-out genes can be utilized to prioritize patients who would benefit from tamoxifen treatment and patients at risk of tamoxifen resistance that should be offered alternative regimens. Funding This work was supported by the Rutgers SHP Dean's research grant, Rutgers start-up funds, Libyan Ministry of Higher Education and Scientific Research, and Katrina Kehlet Graduate Award from The NJ Chapter of the Healthcare Information Management Systems Society.
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Affiliation(s)
- Sarra M Rahem
- Department of Biomedical and Health Informatics, Rutgers School of Health Professions, Rutgers Biomedical and Health Sciences, USA
| | - Nusrat J Epsi
- Department of Biomedical and Health Informatics, Rutgers School of Health Professions, Rutgers Biomedical and Health Sciences, USA
| | - Frederick D Coffman
- Department of Biomedical and Health Informatics, Rutgers School of Health Professions, Rutgers Biomedical and Health Sciences, USA; Department of Physician Assistant Studies and Practice, USA; Department of Pathology & Laboratory Medicine, New Jersey Medical School, Newark, New Jersey 07107, USA
| | - Antonina Mitrofanova
- Department of Biomedical and Health Informatics, Rutgers School of Health Professions, Rutgers Biomedical and Health Sciences, USA; Rutgers Cancer Institute of New Jersey, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901, USA.
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10
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Emanuelli G, Nassehzadeh-Tabriz N, Morrell NW, Marciniak SJ. The integrated stress response in pulmonary disease. Eur Respir Rev 2020; 29:29/157/200184. [PMID: 33004527 PMCID: PMC7116220 DOI: 10.1183/16000617.0184-2020] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2020] [Accepted: 07/15/2020] [Indexed: 02/07/2023] Open
Abstract
The respiratory tract and its resident immune cells face daily exposure
to stress, both from without and from within. Inhaled pathogens, including
severe acute respiratory syndrome coronavirus 2, and toxins from pollution
trigger a cellular defence system that reduces protein synthesis to minimise
viral replication or the accumulation of misfolded proteins. Simultaneously, a
gene expression programme enhances antioxidant and protein folding machineries
in the lung. Four kinases (PERK, PKR, GCN2 and HRI) sense a diverse range of
stresses to trigger this “integrated stress response”. Here we review recent
advances identifying the integrated stress response as a critical pathway in the
pathogenesis of pulmonary diseases, including pneumonias, thoracic malignancy,
pulmonary fibrosis and pulmonary hypertension. Understanding the integrated
stress response provides novel targets for the development of therapies.
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Affiliation(s)
- Giulia Emanuelli
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge, UK.,Division of Respiratory Medicine, Dept of Medicine, University of Cambridge, Cambridge, UK.,Equal first authors
| | - Nikou Nassehzadeh-Tabriz
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge, UK.,Equal first authors
| | - Nick W Morrell
- Division of Respiratory Medicine, Dept of Medicine, University of Cambridge, Cambridge, UK
| | - Stefan J Marciniak
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge, UK .,Division of Respiratory Medicine, Dept of Medicine, University of Cambridge, Cambridge, UK
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11
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Clarisse D, Offner F, De Bosscher K. Latest perspectives on glucocorticoid-induced apoptosis and resistance in lymphoid malignancies. Biochim Biophys Acta Rev Cancer 2020; 1874:188430. [PMID: 32950642 DOI: 10.1016/j.bbcan.2020.188430] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 08/13/2020] [Accepted: 09/14/2020] [Indexed: 02/09/2023]
Abstract
Glucocorticoids are essential drugs in the treatment protocols of lymphoid malignancies. These steroidal hormones trigger apoptosis of the malignant cells by binding to the glucocorticoid receptor (GR), which is a member of the nuclear receptor superfamily. Long term glucocorticoid treatment is limited by two major problems: the development of glucocorticoid-related side effects, which hampers patient quality of life, and the emergence of glucocorticoid resistance, which is a gradual process that is inevitable in many patients. This emphasizes the need to reevaluate and optimize the widespread use of glucocorticoids in lymphoid malignancies. To achieve this goal, a deep understanding of the mechanisms governing glucocorticoid responsiveness is required, yet, a recent comprehensive overview is currently lacking. In this review, we examine how glucocorticoids mediate apoptosis by detailing GR's genomic and non-genomic action mechanisms in lymphoid malignancies. We continue with a discussion of the glucocorticoid-related problems and how these are intertwined with one another. We further zoom in on glucocorticoid resistance by critically analyzing the plethora of proposed mechanisms and highlighting therapeutic opportunities that emerge from these studies. In conclusion, early detection of glucocorticoid resistance in patients remains an important challenge as this would result in a timelier treatment reorientation and reduced glucocorticoid-instigated side effects.
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Affiliation(s)
- Dorien Clarisse
- Translational Nuclear Receptor Research, VIB-UGent Center for Medical Biotechnology, Ghent, Belgium; Department of Biomolecular Medicine, Ghent University, Ghent, Belgium; Cancer Research Institute Ghent (CRIG), Ghent, Belgium.
| | - Fritz Offner
- Cancer Research Institute Ghent (CRIG), Ghent, Belgium; Department of Internal Medicine and Pediatrics, Ghent University Hospital, Ghent, Belgium
| | - Karolien De Bosscher
- Translational Nuclear Receptor Research, VIB-UGent Center for Medical Biotechnology, Ghent, Belgium; Department of Biomolecular Medicine, Ghent University, Ghent, Belgium; Cancer Research Institute Ghent (CRIG), Ghent, Belgium.
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12
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In vitro and ex vivo gene expression profiling reveals differential kinetic response of HSPs and UPR genes is associated with PI resistance in multiple myeloma. Blood Cancer J 2020; 10:78. [PMID: 32724061 PMCID: PMC7387444 DOI: 10.1038/s41408-020-00344-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Revised: 05/16/2020] [Accepted: 05/21/2020] [Indexed: 12/18/2022] Open
Abstract
Extensive inter-individual variation in response to chemotherapy (sensitive vs resistant tumors) is a serious cause of concern in the treatment of multiple myeloma (MM). In this study, we used human myeloma cell lines (HMCLs), and patient-derived CD138+ cells to compare kinetic changes in gene expression patterns between innate proteasome inhibitor (PI)-sensitive and PI-resistant HMCLs following test dosing with the second-generation PI Ixazomib. We found 1553 genes that changed significantly post treatment in PI-sensitive HMCLs compared with only seven in PI-resistant HMCLs (p < 0.05). Genes that were uniquely regulated in PI-resistant lines were RICTOR (activated), HNF4A, miR-16-5p (activated), MYCN (inhibited), and MYC (inhibited). Ingenuity pathway analysis (IPA) using top kinetic response genes identified the proteasome ubiquitination pathway (PUP), and nuclear factor erythroid 2-related factor 2 (NRF2)-mediated oxidative stress response as top canonical pathways in Ix-sensitive cell lines and patient-derived cells, whereas EIF2 signaling and mTOR signaling pathways were unique to PI resistance. Further, 10 genes were common between our in vitro and ex vivo post-treatment kinetic PI response profiles and Shaughnessy’s GEP80-postBz gene expression signature, including the high-risk PUP gene PSMD4. Notably, we found that heat shock proteins and PUP pathway genes showed significant higher upregulation in Ix-sensitive lines compared with the fold-change in Ix-resistant myelomas.
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13
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Heme-regulated eIF2α kinase in erythropoiesis and hemoglobinopathies. Blood 2020; 134:1697-1707. [PMID: 31554636 DOI: 10.1182/blood.2019001915] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Accepted: 09/11/2019] [Indexed: 12/12/2022] Open
Abstract
As essential components of hemoglobin, iron and heme play central roles in terminal erythropoiesis. The impairment of this process in iron/heme deficiency results in microcytic hypochromic anemia, the most prevalent anemia globally. Heme-regulated eIF2α kinase, also known as heme-regulated inhibitor (HRI), is a key heme-binding protein that senses intracellular heme concentrations to balance globin protein synthesis with the amount of heme available for hemoglobin production. HRI is activated during heme deficiency to phosphorylate eIF2α (eIF2αP), which simultaneously inhibits the translation of globin messenger RNAs (mRNAs) and selectively enhances the translation of activating transcription factor 4 (ATF4) mRNA to induce stress response genes. This coordinated translational regulation is a universal hallmark across the eIF2α kinase family under various stress conditions and is termed the integrated stress response (ISR). Inhibition of general protein synthesis by HRI-eIF2αP in erythroblasts is necessary to prevent proteotoxicity and maintain protein homeostasis in the cytoplasm and mitochondria. Additionally, the HRI-eIF2αP-ATF4 pathway represses mechanistic target of rapamycin complex 1 (mTORC1) signaling, specifically in the erythroid lineage as a feedback mechanism of erythropoietin-stimulated erythropoiesis during iron/heme deficiency. Furthermore, ATF4 target genes are most highly activated during iron deficiency to maintain mitochondrial function and redox homeostasis, as well as to enable erythroid differentiation. Thus, heme and translation regulate erythropoiesis through 2 key signaling pathways, ISR and mTORC1, which are coordinated by HRI to circumvent ineffective erythropoiesis (IE). HRI-ISR is also activated to reduce the severity of β-thalassemia intermedia in the Hbbth1/th1 murine model. Recently, HRI has been implicated in the regulation of human fetal hemoglobin production. Therefore, HRI-ISR has emerged as a potential therapeutic target for hemoglobinopathies.
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14
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Stevens AM, Xiang M, Heppler LN, Tošić I, Jiang K, Munoz JO, Gaikwad AS, Horton TM, Long X, Narayanan P, Seashore EL, Terrell MC, Rashid R, Krueger MJ, Mangubat-Medina AE, Ball ZT, Sumazin P, Walker SR, Hamada Y, Oyadomari S, Redell MS, Frank DA. Atovaquone is active against AML by upregulating the integrated stress pathway and suppressing oxidative phosphorylation. Blood Adv 2019; 3:4215-4227. [PMID: 31856268 PMCID: PMC6929386 DOI: 10.1182/bloodadvances.2019000499] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2019] [Accepted: 11/11/2019] [Indexed: 12/31/2022] Open
Abstract
Atovaquone, a US Food and Drug Administration-approved antiparasitic drug previously shown to reduce interleukin-6/STAT3 signaling in myeloma cells, is well tolerated, and plasma concentrations of 40 to 80 µM have been achieved with pediatric and adult dosing. We conducted preclinical testing of atovaquone with acute myeloid leukemia (AML) cell lines and pediatric patient samples. Atovaquone induced apoptosis with an EC50 <30 µM for most AML lines and primary pediatric AML specimens. In NSG mice xenografted with luciferase-expressing THP-1 cells and in those receiving a patient-derived xenograft, atovaquone-treated mice demonstrated decreased disease burden and prolonged survival. To gain a better understanding of the mechanism of atovaquone, we performed an integrated analysis of gene expression changes occurring in cancer cell lines after atovaquone exposure. Atovaquone promoted phosphorylation of eIF2α, a key component of the integrated stress response and master regulator of protein translation. Increased levels of phosphorylated eIF2α led to greater abundance of the transcription factor ATF4 and its target genes, including proapoptotic CHOP and CHAC1. Furthermore, atovaquone upregulated REDD1, an ATF4 target gene and negative regulator of the mechanistic target of rapamycin (mTOR), and caused REDD1-mediated inhibition of mTOR activity with similar efficacy as rapamycin. Additionally, atovaquone suppressed the oxygen consumption rate of AML cells, which has specific implications for chemotherapy-resistant AML blasts that rely on oxidative phosphorylation for survival. Our results provide insight into the complex biological effects of atovaquone, highlighting its potential as an anticancer therapy with novel and diverse mechanisms of action, and support further clinical evaluation of atovaquone for pediatric and adult AML.
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MESH Headings
- Activating Transcription Factor 4/metabolism
- Adolescent
- Animals
- Apoptosis/drug effects
- Atovaquone/pharmacology
- Cell Line, Tumor
- Cell Survival/drug effects
- Child
- Child, Preschool
- Disease Models, Animal
- Female
- Humans
- Infant
- Leukemia, Myeloid, Acute/genetics
- Leukemia, Myeloid, Acute/metabolism
- Leukemia, Myeloid, Acute/mortality
- Leukemia, Myeloid, Acute/pathology
- Male
- Mice
- Mice, Knockout
- Oxidative Phosphorylation/drug effects
- Signal Transduction/drug effects
- Xenograft Model Antitumor Assays
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Affiliation(s)
- Alexandra M Stevens
- Division of Pediatric Hematology/Oncology, Department of Pediatrics, Baylor College of Medicine, Houston, TX
| | - Michael Xiang
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA
| | - Lisa N Heppler
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA
| | - Isidora Tošić
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA
- Department of Biochemistry, Faculty of Medicine, University of Novi Sad, Novi Sad, Serbia
| | - Kevin Jiang
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA
| | - Jaime O Munoz
- Division of Pediatric Hematology/Oncology, Department of Pediatrics, Baylor College of Medicine, Houston, TX
| | - Amos S Gaikwad
- Division of Pediatric Hematology/Oncology, Department of Pediatrics, Baylor College of Medicine, Houston, TX
| | - Terzah M Horton
- Division of Pediatric Hematology/Oncology, Department of Pediatrics, Baylor College of Medicine, Houston, TX
| | - Xin Long
- Division of Pediatric Hematology/Oncology, Department of Pediatrics, Baylor College of Medicine, Houston, TX
| | - Padmini Narayanan
- Division of Pediatric Hematology/Oncology, Department of Pediatrics, Baylor College of Medicine, Houston, TX
| | - Elizabeth L Seashore
- Division of Pediatric Hematology/Oncology, Department of Pediatrics, Baylor College of Medicine, Houston, TX
| | - Maci C Terrell
- Division of Pediatric Hematology/Oncology, Department of Pediatrics, Baylor College of Medicine, Houston, TX
| | - Raushan Rashid
- Division of Pediatric Hematology/Oncology, Department of Pediatrics, Baylor College of Medicine, Houston, TX
| | - Michael J Krueger
- Division of Pediatric Hematology/Oncology, Department of Pediatrics, Baylor College of Medicine, Houston, TX
| | | | | | - Pavel Sumazin
- Division of Pediatric Hematology/Oncology, Department of Pediatrics, Baylor College of Medicine, Houston, TX
| | - Sarah R Walker
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA; and
| | - Yoshimasa Hamada
- Division of Molecular Biology, Institute for Genome Research, and
- Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
| | - Seiichi Oyadomari
- Division of Molecular Biology, Institute for Genome Research, and
- Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
| | - Michele S Redell
- Division of Pediatric Hematology/Oncology, Department of Pediatrics, Baylor College of Medicine, Houston, TX
| | - David A Frank
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA
- Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA; and
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15
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Zhang Q, Du R, Reis Monteiro Dos Santos GR, Yefidoff-Freedman R, Bohm A, Halperin J, Chorev M, Aktas BH. New activators of eIF2α Kinase Heme-Regulated Inhibitor (HRI) with improved biophysical properties. Eur J Med Chem 2019; 187:111973. [PMID: 31881453 DOI: 10.1016/j.ejmech.2019.111973] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 12/13/2019] [Accepted: 12/13/2019] [Indexed: 01/21/2023]
Abstract
Heme-regulated inhibitor (HRI), a eukaryotic translation initiation factor 2 alpha (eIF2α) kinase, is critically important for coupling protein synthesis to heme availability in reticulocytes and adaptation to various environmental stressors in all cells. HRI modifies the severity of several hemoglobin misfolding disorders including β-thalassemia. Small molecule activators of HRI are essential for studying normal- and patho-biology of this kinase as well as for the treatment of various human disorders for which activation of HRI or phosphorylation of eIF2α may be beneficial. We previously reported development of 1-((1,4-trans)-4-aryloxycyclohexyl)-3-arylureas (cHAUs) as specific HRI activators and demonstrated their potential as molecular probes for studying HRI biology and as lead compounds for treatment of various human disorders. To develop more druglike cHAUs for in vivo studies and drug development and to expand the chemical space, we undertook bioassay guided structure-activity relationship studies replacing cyclohexyl ring with various 4-6-membered rings and explored further substitutions on the N-phenyl ring. We tested all analogs in the surrogate eIF2α phosphorylation and cell proliferation assays, and a subset of analogs in secondary mechanistic assays that included endogenous eIF2α phosphorylation and expression of C/EBP homologous protein (CHOP), a downstream effector. Finally, we determined specificity of these compounds for HRI by testing their anti-proliferative activity in cells transfected with siRNA targeting HRI or mock. These compounds have significantly improved cLogPs with no loss of potencies, making them excellent candidates for lead optimization for development of investigational new drugs that potently and specifically activate HRI.
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Affiliation(s)
- Qingwen Zhang
- Division of Medicinal and Process Chemistry, Shanghai Institute of Pharmaceutical Industry, Pudong, Shanghai, 201203, China; Hematology Laboratory for Translational Research, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, 02115, USA
| | - Ronghui Du
- Hematology Laboratory for Translational Research, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, 02115, USA; Medicine School of Nanjing University, Nanjing, Jiangsu, 210093, China
| | | | - Revital Yefidoff-Freedman
- Hematology Laboratory for Translational Research, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, 02115, USA
| | - Andrew Bohm
- Tufts University Medical School, Boston, MA, 02117, USA
| | - Jose Halperin
- Hematology Laboratory for Translational Research, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, 02115, USA
| | - Michael Chorev
- Hematology Laboratory for Translational Research, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, 02115, USA
| | - Bertal H Aktas
- Hematology Laboratory for Translational Research, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, 02115, USA.
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16
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Khan AM, Devarakonda S, Bumma N, Chaudhry M, Benson DM. Potential of NK cells in multiple Myeloma therapy. Expert Rev Hematol 2019; 12:425-435. [PMID: 31070067 DOI: 10.1080/17474086.2019.1617128] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Introduction: Despite rapid advances in myeloma treatment with the development of new drugs, curative therapies remain elusive. Relapsed/refractory disease related to progressive dysregulation of immune system and acquired genetic abnormalities continues to be a major obstacle in achieving cure. Immune-based therapy harnessing the host defense mechanism of natural killer (NK) cells is a promising avenue in the treatment of myeloma. Areas covered: Here, we discuss the biology and cytotoxic activity of NK cells and the potential role of these innate immune cells in defense against cancer and specifically multiple myeloma. We also discuss the role of NK cells in the anti-myeloma effects of autologous and allogeneic stem cell transplantation, various novel drugs, and treatment modalities such as chimeric antigen receptor therapy. Immune evasion, either directly or indirectly involving NK cell dysfunction, may be a key and under-recognized mechanism in myeloma progression. We reviewed extensive literature identified using the keywords immunotherapy, natural killer cells, and multiple myeloma. Expert opinion: Novel treatment approaches in myeloma utilizing the immunomodulatory and cytotoxic properties of NK cells to eradicate resistant and quiescent clones could pave the way for potentially curative interventions.
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Affiliation(s)
- Abdullah M Khan
- a Division of Hematology, Department of Medicine , The Ohio State University Comprehensive Cancer Center , Columbus , OH , USA
| | - Srinivas Devarakonda
- a Division of Hematology, Department of Medicine , The Ohio State University Comprehensive Cancer Center , Columbus , OH , USA
| | - Naresh Bumma
- a Division of Hematology, Department of Medicine , The Ohio State University Comprehensive Cancer Center , Columbus , OH , USA
| | - Maria Chaudhry
- a Division of Hematology, Department of Medicine , The Ohio State University Comprehensive Cancer Center , Columbus , OH , USA
| | - Don M Benson
- a Division of Hematology, Department of Medicine , The Ohio State University Comprehensive Cancer Center , Columbus , OH , USA
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17
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Burwick N, Sharma S. Glucocorticoids in multiple myeloma: past, present, and future. Ann Hematol 2018; 98:19-28. [PMID: 30073393 DOI: 10.1007/s00277-018-3465-8] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 07/26/2018] [Indexed: 12/14/2022]
Abstract
Glucocorticoids are a backbone of treatment for multiple myeloma in both the upfront and relapsed/refractory setting. While glucocorticoids have single agent activity in multiple myeloma, in the modern era, they are paired with novel agents to induce high clinical response rates. On the other hand, toxicities of steroid therapy limit high dose delivery and impact patient quality of life. We provide a history of steroid use in multiple myeloma with the aim to understand how steroids have emerged and persisted in the treatment of multiple myeloma. We review mechanisms of glucocorticoid sensitivity and resistance and highlight potential future directions to evaluate steroid responsiveness. Further research in this area will aid in optimizing steroid utilization and help determine when glucocorticoid therapy may no longer benefit patients.
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Affiliation(s)
- Nicholas Burwick
- VA Puget Sound Health Care System, Seattle, WA, USA. .,Department of Medicine, University of Washington, 1705 NE Pacific St, M/S 358280, Seattle, WA, 98195, USA.
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18
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White MC, Schroeder RD, Zhu K, Xiong K, McConkey DJ. HRI-mediated translational repression reduces proteotoxicity and sensitivity to bortezomib in human pancreatic cancer cells. Oncogene 2018; 37:4413-4427. [PMID: 29720726 PMCID: PMC6138554 DOI: 10.1038/s41388-018-0227-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Revised: 10/26/2017] [Accepted: 11/03/2017] [Indexed: 12/31/2022]
Abstract
Human cancer cells display extensive heterogeneity in their sensitivities to the proteasome inhibitor bortezomib (Velcade). The molecular mechanisms underlying this heterogeneity remain unclear, and strategies to overcome resistance are limited. Here, we discover that inherent differences in eIF2α phosphorylation among a panel of ten human pancreatic cancer cell lines significantly impacts bortezomib sensitivity, and implicate the HRI (heme-regulated inhibitor) eIF2α kinase as a novel therapeutic target. Within our panel, we identified a subset of cell lines with defective induction of eIF2α phosphorylation, conferring a high degree of sensitivity to bortezomib. These bortezomib-sensitive cells exhibited impaired translation attenuation followed by toxic accumulation of protein aggregates and reactive oxygen species (ROS), whereas the bortezomib-resistant cell lines displayed increased phosphorylation of eIF2α, decreased translation, few protein aggregates, and minimal ROS production. Importantly, we identified HRI as the primary bortezomib-activated eIF2α kinase, and demonstrated that HRI knockdown promoted cell death in the bortezomib-resistant cells. Overall, our data implicate inducible HRI-mediated phosphorylation of eIF2α as a central cytoprotective mechanism following exposure to bortezomib and provide proof-of-concept for the development of HRI inhibitors to overcome proteasome inhibitor resistance.
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Affiliation(s)
- Matthew C White
- Departments of Urology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA.,Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA.,The Program in Experimental Therapeutics, The University of Texas Graduate School of Biomedical Sciences, Houston, TX, 77030, USA
| | - Rebecca D Schroeder
- The Program in Experimental Therapeutics, The University of Texas Graduate School of Biomedical Sciences, Houston, TX, 77030, USA
| | - Keyi Zhu
- Departments of Urology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA.,Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - Katherine Xiong
- Departments of Urology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA.,Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA
| | - David J McConkey
- Departments of Urology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA. .,Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, 77030, USA. .,The Program in Experimental Therapeutics, The University of Texas Graduate School of Biomedical Sciences, Houston, TX, 77030, USA. .,Johns Hopkins Greenberg Bladder Cancer Institute, Baltimore, MD, 21287, USA.
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19
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Patent highlights from December 2017 to January 2018. Pharm Pat Anal 2018; 7:111-119. [PMID: 29676211 DOI: 10.4155/ppa-2018-0003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A snapshot of noteworthy recent developments in the patent literature of relevance to pharmaceutical and medical research and development.
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20
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Burwick N, Aktas BH. The eIF2-alpha kinase HRI: a potential target beyond the red blood cell. Expert Opin Ther Targets 2017; 21:1171-1177. [PMID: 29063813 DOI: 10.1080/14728222.2017.1397133] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
INTRODUCTION The eIF2α kinase heme-regulated inhibitor (HRI) is one of four well-described kinases that phosphorylate eIF2α in response to various cell stressors, resulting in reduced ternary complex formation and attenuation of mRNA translation. Although HRI is well known for its role as a heme sensor in erythroid progenitors, pharmacologic activation of HRI has been demonstrated to have anti-cancer activity across a wide range of tumor sub-types. Here, the potential of HRI activators as novel cancer therapeutics is explored. Areas covered: We provide an introduction to eIF2 signaling pathways in general, and specifically review data on the eIF2α kinase HRI in erythroid and non-erythroid cells. We review aspects of targeting eIF2 signaling in cancer and highlight promising data using HRI activators against tumor cells. Expert opinion: Pharmacologic activation of HRI inhibits tumor growth as a single agent without appreciable toxicity in vivo. The ability of HRI activators to provide direct and sustained eIF2α phosphorylation without inducing oxidative stress or broad eIF2α kinase activation may be especially advantageous for tolerability. Combination therapy with established therapeutics may further augment anti-cancer activity to overcome disease resistance.
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Affiliation(s)
- Nicholas Burwick
- a Division of hematology , VA Puget Sound Health Care System , Seattle , WA , USA.,b Division of Hematology , University of Washington School of Medicine , Seattle WA , USA
| | - Bertal H Aktas
- c Department of Medicine , Brigham and Women's Hospital and Harvard Medical School , Boston , MA , USA
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