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Kondo A, Tanaka H, Rai S, Shima H, Matsumura I, Watanabe T. Depletion of Ppp6c in hematopoietic and vascular endothelial cells causes embryonic lethality and decreased hematopoietic potential. Exp Hematol 2024; 133:104205. [PMID: 38490577 DOI: 10.1016/j.exphem.2024.104205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 03/02/2024] [Accepted: 03/04/2024] [Indexed: 03/17/2024]
Abstract
Protein phosphatase 6 (PP6) is a serine/threonine (Ser/Thr) protein phosphatase, and its catalytic subunit is Ppp6c. PP6 forms the PP2A subfamily with PP2A and PP4. The diverse phenotypes observed following small interfering RNA (siRNA)-based knockdown of Ppp6c in cultured mammalian cells suggest that PP6 plays roles in cell growth and DNA repair. There is also evidence that PP6 regulates nuclear factor kappa B (NF-κB) signaling and mitogen-activated protein kinases and inactivates transforming growth factor-β-activated kinase 1 (TAK1). Loss of Ppp6c causes several abnormalities, including those of T cell and regulatory T cell function, neurogenesis, oogenesis, and spermatogenesis. PP2A has been reported to play an important role in erythropoiesis. However, the roles of PP6 in other hematopoietic cells have not been investigated. We generated Ppp6cfl/fl;Tie2-Cre (Ppp6cTKO) mice, in which Ppp6c was specifically deleted in hematopoietic and vascular endothelial cells. Ppp6cTKO mice displayed embryonic lethality. Ppp6c deficiency increased the number of dead cells and decreased the percentages of erythroid and monocytic cells during fetal hematopoiesis. By contrast, the number of Lin-Sca-1+c-Kit+ cells, which give rise to all hematopoietic cells, was slightly increased, but their colony-forming cell activity was markedly decreased. Ppp6c deficiency also increased phosphorylation of extracellular signal-regulated kinase 1/2 and c-Jun amino (N)-terminal kinase in fetal liver hematopoietic cells.
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Affiliation(s)
- Ayumi Kondo
- Department of Biological Science, Graduate School of Humanities and Sciences, Nara Women's University, Nara, Japan
| | - Hirokazu Tanaka
- Department of Hematology and Rheumatology, Kindai University Faculty of Medicine, Osaka-Sayama, Osaka, Japan
| | - Shinya Rai
- Department of Hematology and Rheumatology, Kindai University Faculty of Medicine, Osaka-Sayama, Osaka, Japan
| | - Hiroshi Shima
- Division of Cancer Chemotherapy, Miyagi Cancer Center Research Institute, Natori, Miyagi, Japan
| | - Itaru Matsumura
- Department of Hematology and Rheumatology, Kindai University Faculty of Medicine, Osaka-Sayama, Osaka, Japan
| | - Toshio Watanabe
- Department of Biological Science, Graduate School of Humanities and Sciences, Nara Women's University, Nara, Japan.
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2
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Sun SJ, Aguirre-Gamboa R, de Bree LCJ, Sanz J, Dumaine A, Joosten LA, Divangahi M, Netea MG, Barreiro LB. BCG vaccination impacts the epigenetic landscape of progenitor cells in human bone marrow. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.28.569076. [PMID: 38077046 PMCID: PMC10705418 DOI: 10.1101/2023.11.28.569076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
While the Bacille-Calmette-Guérin (BCG) vaccine is used to prevent tuberculosis, it also offers protection against a diverse range of non-mycobacterial infections. However, the underlying protective mechanisms in humans are not yet fully understood. Here, we surveyed at single-cell resolution the gene expression and chromatin landscape of human bone marrow, aspirated before and 90 days after BCG vaccination or placebo administration. We show that BCG vaccination significantly alters both the gene expression and epigenetic profiles of human hematopoietic stem and progenitor cells (HSPCs). Changes in gene expression occur primarily on the most uncommitted stem cells and are reflective of a persistent myeloid bias. In contrast, BCG-induced changes in chromatin accessibility are most prevalent within differentiated progenitor cells at sites influenced by Kruppel-like factor (KLF)/SP and EGR transcription factors (TFs). These TFs are also activated in the most uncommitted stem cells, indicating that activated TFs, which drive persistent changes in HSC gene expression, likely also drive chromatin dynamics appearing within downstream progenitor cells. This perspective contests the prevailing notion that epigenetic modifications linked to innate immune memory transfer directly from stem cells to their differentiated derivatives. Finally, we show that alterations in gene expression and chromatin accessibility in HSPCs due to BCG vaccination were highly correlated (r>0.8) with the IL-1β secretion capacity of paired PBMCs upon secondary immune challenge. Overall, our findings shed light on BCG vaccination's profound and lasting effects on HSPCs and its influence on innate immune responses.
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Affiliation(s)
- Sarah J. Sun
- Committee on Immunology, University of Chicago, Chicago, IL, USA
- Medical Scientist Training program, University of Chicago, Chicago, IL, USA
| | - Raúl Aguirre-Gamboa
- Section of Genetic Medicine, Department of Medicine, University of Chicago, Chicago, IL, USA
| | - L. Charlotte J. de Bree
- Department of Internal Medicine and Radbound Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Joaquin Sanz
- Institute for Biocomputation and Physics of Complex Systems (BIFI) and Dept. of Theoretical Physics, University of Zaragoza, Zaragoza, Spain
| | - Anne Dumaine
- Section of Genetic Medicine, Department of Medicine, University of Chicago, Chicago, IL, USA
| | - Leo A.B. Joosten
- Department of Internal Medicine and Radbound Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, the Netherlands
- Department of Medical Genetics, Iuliu Hatieganu University of Medicine and Pharmacy, Cluj-Napoca, Romania
| | - Maziar Divangahi
- Department of Internal Medicine and Radbound Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, the Netherlands
- Department of Medicine, Meakins-Christie Laboratories, Research Institute McGill University Health Centre, McGill University, Montreal, Canada
| | - Mihai G. Netea
- Department of Internal Medicine and Radbound Center for Infectious Diseases, Radboud University Medical Center, Nijmegen, the Netherlands
- Department of Immunology and Metabolism, Life and Medical Sciences Institute, University of Bonn, Bonn, Germany
| | - Luis B. Barreiro
- Committee on Immunology, University of Chicago, Chicago, IL, USA
- Section of Genetic Medicine, Department of Medicine, University of Chicago, Chicago, IL, USA
- Department of Human Genetics, University of Chicago, Chicago, IL, USA
- Committee on Genetics, Genomics, and Systems Biology, University of Chicago, Chicago, IL, USA
- Lead contact
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3
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Olson WJ, Derudder E. The miR-142 miRNAs: Shaping the naïve immune system. Immunol Lett 2023; 261:37-46. [PMID: 37459958 DOI: 10.1016/j.imlet.2023.07.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Revised: 06/21/2023] [Accepted: 07/10/2023] [Indexed: 08/01/2023]
Abstract
Immunity in a naïve organism is tightly controlled. Adequate proportions of the many immune cell subsets must be produced to mount efficient responses to eventual challenges. In addition, a functioning immune system is highly dynamic at steady state. Mature immune cells must be positioned properly and/or circulate to facilitate the detection of dangers. They must also be poised to promptly react to unusual encounters, while ignoring innocuous germs and self. Numerous regulatory mechanisms act at the molecular level to generate such an exquisite structure, including miRNA-mediated repression of protein synthesis. Notably, the miRNAs from the miR-142 locus are preferentially expressed in hematopoietic cells. Their importance is underscored by the deeply disturbed immune system seen upon inactivation of the locus in mice. In this review, we explore reported roles for the miR-142 miRNAs in the shaping of immunity in vertebrates, discussing in particular their contributions to the generation, migration and survival of hematopoietic cells.
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Affiliation(s)
- William J Olson
- Institute for Biomedical Aging Research, University of Innsbruck, Innsbruck, Austria
| | - Emmanuel Derudder
- Institute for Biomedical Aging Research, University of Innsbruck, Innsbruck, Austria.
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4
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Akıncılar SC, Wu L, NG QF, Chua JYH, Unal B, Noda T, Chor WHJ, Ikawa M, Tergaonkar V. NAIL: an evolutionarily conserved lncRNA essential for licensing coordinated activation of p38 and NFκB in colitis. Gut 2021; 70:1857-1871. [PMID: 33239342 PMCID: PMC8458091 DOI: 10.1136/gutjnl-2020-322980] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 10/19/2020] [Accepted: 10/29/2020] [Indexed: 12/14/2022]
Abstract
OBJECTIVE NFκB is the key modulator in inflammatory disorders. However, the key regulators that activate, fine-tune or shut off NFκB activity in inflammatory conditions are poorly understood. In this study, we aim to investigate the roles that NFκB-specific long non-coding RNAs (lncRNAs) play in regulating inflammatory networks. DESIGN Using the first genetic-screen to identify NFκB-specific lncRNAs, we performed RNA-seq from the p65-/- and Ikkβ-/- mouse embryonic fibroblasts and report the identification of an evolutionary conserved lncRNA designated mNAIL (mice) or hNAIL (human). hNAIL is upregulated in human inflammatory disorders, including UC. We generated mNAILΔNFκB mice, wherein deletion of two NFκB sites in the proximal promoter of mNAIL abolishes its induction, to study its function in colitis. RESULTS NAIL regulates inflammation via sequestering and inactivating Wip1, a known negative regulator of proinflammatory p38 kinase and NFκB subunit p65. Wip1 inactivation leads to coordinated activation of p38 and covalent modifications of NFκB, essential for its genome-wide occupancy on specific targets. NAIL enables an orchestrated response for p38 and NFκB coactivation that leads to differentiation of precursor cells into immature myeloid cells in bone marrow, recruitment of macrophages to inflamed area and expression of inflammatory genes in colitis. CONCLUSION NAIL directly regulates initiation and progression of colitis and its expression is highly correlated with NFκB activity which makes it a perfect candidate to serve as a biomarker and a therapeutic target for IBD and other inflammation-associated diseases.
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Affiliation(s)
- Semih Can Akıncılar
- Laboratory of NFκB Signalling, Institute of Molecular and Cell Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Institute of Molecular and Cell Biology, Singapore
| | - Lele Wu
- Laboratory of NFκB Signalling, Institute of Molecular and Cell Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Institute of Molecular and Cell Biology, Singapore
| | - Qin Feng NG
- Laboratory of NFκB Signalling, Institute of Molecular and Cell Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Institute of Molecular and Cell Biology, Singapore
| | - Joelle Yi Heng Chua
- Laboratory of NFκB Signalling, Institute of Molecular and Cell Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Institute of Molecular and Cell Biology, Singapore
| | - Bilal Unal
- Laboratory of NFκB Signalling, Institute of Molecular and Cell Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Institute of Molecular and Cell Biology, Singapore
| | - Taichi Noda
- Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Wei Hong Jeff Chor
- Laboratory of NFκB Signalling, Institute of Molecular and Cell Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Institute of Molecular and Cell Biology, Singapore
| | - Masahito Ikawa
- Research Institute for Microbial Diseases, Osaka University, Osaka, Japan
| | - Vinay Tergaonkar
- Laboratory of NFκB Signalling, Institute of Molecular and Cell Biology (IMCB), A*STAR (Agency for Science, Technology and Research), Institute of Molecular and Cell Biology, Singapore .,Department of Pathology, Yong Loo Lin School of Medicine, National University of Singapore (NUS), Singapore
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Sasaki Y, Guo YM, Goto T, Ubukawa K, Asanuma K, Kobayashi I, Sawada K, Wakui H, Takahashi N. IL-6 Generated from Human Hematopoietic Stem and Progenitor Cells through TLR4 Signaling Promotes Emergency Granulopoiesis by Regulating Transcription Factor Expression. THE JOURNAL OF IMMUNOLOGY 2021; 207:1078-1086. [PMID: 34341172 DOI: 10.4049/jimmunol.2100168] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 06/16/2021] [Indexed: 11/19/2022]
Abstract
Emergency granulopoiesis, also known as demand-adapted granulopoiesis, is defined as the response of an organism to systemic bacterial infections, and it results in neutrophil mobilization from reservoir pools and increased myelopoiesis in the bone marrow. Indirect and direct initiating mechanisms of emergency granulopoiesis have been hypothesized. However, the detailed mechanism of hyperactive myelopoiesis in the bone marrow, which leads to granulocyte left shift, remains unknown. In this study, we report that TLR4 is expressed on granulo-monocytic progenitors, as well as mobilized human peripheral blood CD34+ cells, which account for 0.2% of monocytes in peripheral blood, and ∼ 10% in bone marrow. LPS, a component of Gram-negative bacteria that results in a systemic bacterial infection, induces the differentiation of peripheral blood CD34+ cells into myelocytes and monocytes in vitro via the TLR4 signaling pathway. Moreover, CD34+ cells directly responded to LPS stimulation by activating the MAPK and NF-κB signaling pathways, and they produced IL-6 that promotes emergency granulopoiesis by phosphorylating C/EBPα and C/EBPβ, and this effect was suppressed by the action of an IL-6 receptor inhibitor. This work supports the finding that TLR is expressed on human hematopoietic stem and progenitor cells, and it provides evidence that human hematopoietic stem and progenitor cells can directly sense pathogens and produce cytokines exerting autocrine and/or paracrine effects, thereby promoting differentiation.
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Affiliation(s)
- Yumi Sasaki
- Department of Life Science, Graduate School of Engineering Science, Akita University, Akita, Japan
| | - Yong-Mei Guo
- Department of Hematology, Nephrology, and Rheumatology, Akita University Graduate School of Medicine, Akita, Japan;
| | - Tatsufumi Goto
- Department of Life Science, Graduate School of Engineering Science, Akita University, Akita, Japan
| | - Kumi Ubukawa
- Department of Hematology, Nephrology, and Rheumatology, Akita University Graduate School of Medicine, Akita, Japan
| | - Ken Asanuma
- Division of Radio Isotope, Bioscience Education and Research Support Center, Akita University School of Medicine, Akita, Japan; and
| | - Isuzu Kobayashi
- Department of Hematology, Nephrology, and Rheumatology, Akita University Graduate School of Medicine, Akita, Japan
| | - Kenichi Sawada
- Medical Corporation Hokubukai Utsukushigaoka Hospital, Hokkaido, Japan
| | - Hideki Wakui
- Department of Life Science, Graduate School of Engineering Science, Akita University, Akita, Japan
| | - Naoto Takahashi
- Department of Hematology, Nephrology, and Rheumatology, Akita University Graduate School of Medicine, Akita, Japan
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6
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Germic N, Hosseini A, Yousefi S, Karaulov A, Simon HU. Regulation of eosinophil functions by autophagy. Semin Immunopathol 2021; 43:347-362. [PMID: 34019141 PMCID: PMC8241657 DOI: 10.1007/s00281-021-00860-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Accepted: 04/22/2021] [Indexed: 12/13/2022]
Abstract
Eosinophils are granule-containing leukocytes which develop in the bone marrow. For many years, eosinophils have been recognized as cytotoxic effector cells, but recent studies suggest that they perform additional immunomodulatory and homeostatic functions. Autophagy is a conserved intracellular process which preserves cellular homeostasis. Autophagy defects have been linked to the pathogenesis of many human disorders. Evidence for abnormal regulation of autophagy, including decreased or increased expression of autophagy-related (ATG) proteins, has been reported in several eosinophilic inflammatory disorders, such as Crohn's disease, bronchial asthma, eosinophilic esophagitis, and chronic rhinosinusitis. Despite the increasing extent of research using preclinical models of immune cell-specific autophagy deficiency, the physiological relevance of autophagic pathway in eosinophils has remained unknown until recently. Owing to the increasing evidence that eosinophils play a role in keeping organismal homeostasis, the regulation of eosinophil functions is of considerable interest. Here, we discuss the most recent advances on the role of autophagy in eosinophils, placing particular emphasis on insights obtained in mouse models of infections and malignant diseases in which autophagy has genetically dismantled in the eosinophil lineage. These studies pointed to the possibility that autophagy-deficient eosinophils exaggerate inflammation. Therefore, the pharmacological modulation of the autophagic pathway in these cells could be used for therapeutic interventions.
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Affiliation(s)
- Nina Germic
- Institute of Pharmacology, University of Bern, Inselspital, INO-F, 3010, Bern, Switzerland
| | - Aref Hosseini
- Institute of Pharmacology, University of Bern, Inselspital, INO-F, 3010, Bern, Switzerland
| | - Shida Yousefi
- Institute of Pharmacology, University of Bern, Inselspital, INO-F, 3010, Bern, Switzerland
| | - Alexander Karaulov
- Department of Clinical Immunology and Allergology, Sechenov University, 119991, Moscow, Russia
| | - Hans-Uwe Simon
- Institute of Pharmacology, University of Bern, Inselspital, INO-F, 3010, Bern, Switzerland. .,Department of Clinical Immunology and Allergology, Sechenov University, 119991, Moscow, Russia. .,Laboratory of Molecular Immunology, Institute of Fundamental Medicine and Biology, Kazan Federal University, 420012, Kazan, Russia.
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7
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Nuclear P38: Roles in Physiological and Pathological Processes and Regulation of Nuclear Translocation. Int J Mol Sci 2020; 21:ijms21176102. [PMID: 32847129 PMCID: PMC7504396 DOI: 10.3390/ijms21176102] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 08/20/2020] [Accepted: 08/21/2020] [Indexed: 02/07/2023] Open
Abstract
The p38 mitogen-activated protein kinase (p38MAPK, termed here p38) cascade is a central signaling pathway that transmits stress and other signals to various intracellular targets in the cytoplasm and nucleus. More than 150 substrates of p38α/β have been identified, and this number is likely to increase. The phosphorylation of these substrates initiates or regulates a large number of cellular processes including transcription, translation, RNA processing and cell cycle progression, as well as degradation and the nuclear translocation of various proteins. Being such a central signaling cascade, its dysregulation is associated with many pathologies, particularly inflammation and cancer. One of the hallmarks of p38α/β signaling is its stimulated nuclear translocation, which occurs shortly after extracellular stimulation. Although p38α/β do not contain nuclear localization or nuclear export signals, they rapidly and robustly translocate to the nucleus, and they are exported back to the cytoplasm within minutes to hours. Here, we describe the physiological and pathological roles of p38α/β phosphorylation, concentrating mainly on the ill-reviewed regulation of p38α/β substrate degradation and nuclear translocation. In addition, we provide information on the p38α/β ’s substrates, concentrating mainly on the nuclear targets and their role in p38α/β functions. Finally, we also provide information on the mechanisms of nuclear p38α/β translocation and its use as a therapeutic target for p38α/β-dependent diseases.
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8
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Jaiswal AK, Makhija S, Stahr N, Sandey M, Suryawanshi A, Saxena A, Dagur PK, McCoy JP, Levine SJ, Mishra A. Dendritic Cell-Restricted Progenitors Contribute to Obesity-Associated Airway Inflammation via Adam17-p38 MAPK-Dependent Pathway. Front Immunol 2020; 11:363. [PMID: 32184787 PMCID: PMC7058657 DOI: 10.3389/fimmu.2020.00363] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 02/14/2020] [Indexed: 01/08/2023] Open
Abstract
Proliferation of dendritic cell (DC)—restricted progenitor cells in bone marrow compartment is tightly regulated at steady state and responds to multiple tissue-specific triggers during disturbed homeostasis such as obesity. DCs in the lung stem from a rapidly dividing DC-restricted progenitor cells and are effective at generating adaptive immune responses in allergic airway inflammation. Precisely, how DC-restricted progenitor expansion and differentiation are influenced by airway inflammation to maintain constant supply of myeloid DCs is poorly understood. Here we show that a high fat diet (HFD) induces oxidative stress and accelerates the expansion of DC- restricted progenitor cells in bone marrow and correlates with persistent induction of p38 mitogen activated protein kinase (MAPK), which is blocked with a selective p38α/β MAPK inhibitor. Mice fed a HFD and sensitized to inhaled allergen house dust mite (HDM) led to alterations of DC- restricted progenitor cells that were characterized by increased expansion and seeding of lung DCs in airway inflammation. Mechanistically, we establish that the expansion induced by HFD dysregulates the expression of a disintegrin and metallopeptidase domain 17 (Adam17) and is required for p38 MAPK activation in DC-restricted progenitors. These results demonstrates that obesity produces persistent changes in DC precursors and that elevation of Adam17 expression is tightly coupled to p38 MAPK and is a key driver of proliferation. Altogether, these data provide phenotypic and mechanistic insight into dendritic cell supply chain in obesity-associated airway inflammation.
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Affiliation(s)
- Anil Kumar Jaiswal
- Laboratory of Lung Inflammation, College of Veterinary Medicine, Auburn University, Auburn, AL, United States.,Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL, United States
| | - Sangeet Makhija
- Laboratory of Lung Inflammation, College of Veterinary Medicine, Auburn University, Auburn, AL, United States.,Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL, United States
| | - Natalie Stahr
- Laboratory of Lung Inflammation, College of Veterinary Medicine, Auburn University, Auburn, AL, United States.,Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL, United States
| | - Maninder Sandey
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL, United States
| | - Amol Suryawanshi
- Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL, United States
| | - Ankit Saxena
- Flow Cytometry Core Facility, Division of Intramural Research, National Heart, Lung, and Blood Institute (NHLBI), National Institutes of Health (NIH), Bethesda, MD, United States
| | - Pradeep K Dagur
- Flow Cytometry Core Facility, Division of Intramural Research, National Heart, Lung, and Blood Institute (NHLBI), National Institutes of Health (NIH), Bethesda, MD, United States
| | - J Philip McCoy
- Flow Cytometry Core Facility, Division of Intramural Research, National Heart, Lung, and Blood Institute (NHLBI), National Institutes of Health (NIH), Bethesda, MD, United States
| | - Stewart J Levine
- Laboratory of Asthma and Lung Inflammation, Division of Intramural Research, National Heart, Lung, and Blood Institute (NHLBI), National Institutes of Health (NIH), Bethesda, MD, United States
| | - Amarjit Mishra
- Laboratory of Lung Inflammation, College of Veterinary Medicine, Auburn University, Auburn, AL, United States.,Department of Pathobiology, College of Veterinary Medicine, Auburn University, Auburn, AL, United States
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9
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Sui Z, Sun H, Weng Y, Zhang X, Sun M, Sun R, Zhao B, Liang Z, Zhang Y, Li C, Zhang L. Quantitative proteomics analysis of deer antlerogenic periosteal cells reveals potential bioactive factors in velvet antlers. J Chromatogr A 2020; 1609:460496. [DOI: 10.1016/j.chroma.2019.460496] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 08/17/2019] [Accepted: 08/28/2019] [Indexed: 01/15/2023]
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10
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MAPK p38alpha Kinase Influences Haematopoiesis in Embryonic Stem Cells. Stem Cells Int 2019; 2019:5128135. [PMID: 31281375 PMCID: PMC6589316 DOI: 10.1155/2019/5128135] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 03/14/2019] [Accepted: 04/28/2019] [Indexed: 01/23/2023] Open
Abstract
The activation of p38alpha kinase mediates cell response to various extracellular factors including many interleukins and growth factors important for haematopoiesis. The role of p38alpha kinase was previously analysed in particular haematopoietic cells. In this study and for the first time, the role of p38alpha kinase in haematopoiesis was studied using a model of continuous haematopoietic development in pluripotent embryonic stem cells in vitro. The expression of transcripts associated with haematopoiesis and the potential for the formation of specific haematopoietic cell colonies were compared between wild-type and mutant p38alpha gene-depleted cells. The absence of p38alpha kinase led to the inhibition of hemangioblast formation during the first step of haematopoiesis. Later, during differentiation, due to the lack of p38alpha kinase, erythrocyte maturation was impaired. Mutant p38α−/− cells also exhibited decreased potential with respect to the expansion of granulocyte colony-forming units. This effect was reversed in the absence of erythropoietin as shown by colony-forming unit assay in media for colony-forming unit granulocytes/macrophages. p38alpha kinase thus plays an important role in the differentiation of common myeloid precursor cells into granulocyte lineages.
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11
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Zarrabi M, Afzal E, Ebrahimi M. Manipulation of Hematopoietic Stem Cell Fate by Small Molecule Compounds. Stem Cells Dev 2018; 27:1175-1190. [DOI: 10.1089/scd.2018.0091] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Affiliation(s)
- Morteza Zarrabi
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
- Royan Stem Cell Technology Company, Cord Blood Bank, Tehran, Iran
| | - Elaheh Afzal
- Royan Stem Cell Technology Company, Cord Blood Bank, Tehran, Iran
| | - Marzieh Ebrahimi
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
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12
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Alachkar H, Mutonga M, Malnassy G, Park JH, Fulton N, Woods A, Meng L, Kline J, Raca G, Odenike O, Takamatsu N, Miyamoto T, Matsuo Y, Stock W, Nakamura Y. T-LAK cell-originated protein kinase presents a novel therapeutic target in FLT3-ITD mutated acute myeloid leukemia. Oncotarget 2016; 6:33410-25. [PMID: 26450903 PMCID: PMC4741775 DOI: 10.18632/oncotarget.5418] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 09/22/2015] [Indexed: 11/25/2022] Open
Abstract
Gain-of-function mutations of FLT3 (FLT3-ITD), comprises up to 30% of normal karyotype acute myeloid leukemia (AML) and is associated with an adverse prognosis. Current FLT3 kinase inhibitors have been tested extensively, but have not yet resulted in a survival benefit and novel therapies are awaited. Here we show that T-LAK cell-originated protein kinase (TOPK), a mitotic kinase highly expressed in and correlated with more aggressive phenotype in several types of cancer, is expressed in AML but not in normal CD34+ cells and that TOPK knockdown decreased cell viability and induced apoptosis. Treatment of AML cells with TOPK inhibitor (OTS514) resulted in a dose-dependent decrease in cell viability with lower IC50 in FLT3-mutated cells, including blasts obtained from patients relapsed after FLT3-inhibitor treatment. Using a MV4-11-engrafted mouse model, we found that mice treated with 7.5 mg/kg IV daily for 3 weeks survived significantly longer than vehicle treated mice (median survival 46 vs 29 days, P < 0.001). Importantly, we identified TOPK as a FLT3-ITD and CEBPA regulated kinase, and that modulating TOPK expression or activity resulted in significant decrease of FLT3 expression and CEBPA phosphorylation. Thus, targeting TOPK in FLT3-ITD AML represents a novel therapeutic approach for this adverse risk subset of AML.
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Affiliation(s)
- Houda Alachkar
- Department of Medicine, Section of Hematology/Oncology, University of Chicago, Chicago, IL, USA
| | - Martin Mutonga
- Department of Medicine, Section of Hematology/Oncology, University of Chicago, Chicago, IL, USA
| | - Gregory Malnassy
- Department of Medicine, Section of Hematology/Oncology, University of Chicago, Chicago, IL, USA
| | - Jae-Hyun Park
- Department of Medicine, Section of Hematology/Oncology, University of Chicago, Chicago, IL, USA
| | - Noreen Fulton
- Department of Medicine, Section of Hematology/Oncology, University of Chicago, Chicago, IL, USA
| | - Alex Woods
- Department of Medicine, Section of Hematology/Oncology, University of Chicago, Chicago, IL, USA
| | - Liping Meng
- Department of Medicine, Section of Hematology/Oncology, University of Chicago, Chicago, IL, USA
| | - Justin Kline
- Department of Medicine, Section of Hematology/Oncology, University of Chicago, Chicago, IL, USA
| | - Gordana Raca
- Department of Medicine, Section of Hematology/Oncology, University of Chicago, Chicago, IL, USA
| | - Olatoyosi Odenike
- Department of Medicine, Section of Hematology/Oncology, University of Chicago, Chicago, IL, USA
| | | | | | - Yo Matsuo
- OncoTherapy Science, Inc., Kanagawa, Japan
| | - Wendy Stock
- Department of Medicine, Section of Hematology/Oncology, University of Chicago, Chicago, IL, USA
| | - Yusuke Nakamura
- Department of Medicine, Section of Hematology/Oncology, University of Chicago, Chicago, IL, USA
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13
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Friedman AD. C/EBPα in normal and malignant myelopoiesis. Int J Hematol 2015; 101:330-41. [PMID: 25753223 DOI: 10.1007/s12185-015-1764-6] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Revised: 02/18/2015] [Accepted: 02/19/2015] [Indexed: 12/22/2022]
Abstract
CCAAT/enhancer binding protein α (C/EBPα) dimerizes via its leucine zipper (LZ) domain to bind DNA via its basic region and activate transcription via N-terminal trans-activation domains. The activity of C/EBPα is modulated by several serine/threonine kinases and via sumoylation, its gene is activated by RUNX1 and additional transcription factors, its mRNA stability is modified by miRNAs, and its mRNA is subject to translation control that affects AUG selection. In addition to inducing differentiation, C/EBPα inhibits cell cycle progression and apoptosis. Within hematopoiesis, C/EBPα levels increase as long-term stem cells progress to granulocyte-monocyte progenitors (GMP). Absence of C/EBPα prevents GMP formation, and higher levels are required for granulopoiesis compared to monopoiesis. C/EBPα interacts with AP-1 proteins to bind hybrid DNA elements during monopoiesis, and induction of Gfi-1, C/EBPε, KLF5, and miR-223 by C/EBPα enables granulopoiesis. The CEBPA ORF is mutated in approximately 10 % of acute myeloid leukemias (AML), leading to expression of N-terminally truncated C/EBPαp30 and C-terminal, in-frame C/EBPαLZ variants, which inhibit C/EBPα activities but also play additional roles during myeloid transformation. RUNX1 mutation, CEBPA promoter methylation, Trib1 or Trib2-mediated C/EBPαp42 degradation, and signaling pathways leading to C/EBPα serine 21 phosphorylation reduce C/EBPα expression or activity in additional AML cases.
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Affiliation(s)
- Alan D Friedman
- Division of Pediatric Oncology, Johns Hopkins University, Cancer Research Building I, Room 253, 1650 Orleans Street, Baltimore, MD, 21231, USA,
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14
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Instruction of hematopoietic lineage choice by cytokine signaling. Exp Cell Res 2014; 329:207-13. [PMID: 25046868 DOI: 10.1016/j.yexcr.2014.07.011] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Revised: 07/08/2014] [Accepted: 07/10/2014] [Indexed: 01/06/2023]
Abstract
Hematopoiesis is the cumulative consequence of finely tuned signaling pathways activated through extrinsic factors, such as local niche signals and systemic hematopoietic cytokines. Whether extrinsic factors actively instruct the lineage choice of hematopoietic stem and progenitor cells or are only selectively allowing survival and proliferation of already intrinsically lineage-committed cells has been debated over decades. Recent results demonstrated that cytokines can instruct lineage choice. However, the precise function of individual cytokine-triggered signaling molecules in inducing cellular events like proliferation, lineage choice, and differentiation remains largely elusive. Signal transduction pathways activated by different cytokine receptors are highly overlapping, but support the production of distinct hematopoietic lineages. Cellular context, signaling dynamics, and the crosstalk of different signaling pathways determine the cellular response of a given extrinsic signal. New tools to manipulate and continuously quantify signaling events at the single cell level are therefore required to thoroughly interrogate how dynamic signaling networks yield a specific cellular response.
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15
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IL-4 and IL-13 differentially regulate TLR-induced eosinophil-basophil differentiation of cord blood CD34+ progenitor cells. PLoS One 2014; 9:e100734. [PMID: 24971469 PMCID: PMC4074087 DOI: 10.1371/journal.pone.0100734] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2013] [Accepted: 05/30/2014] [Indexed: 11/20/2022] Open
Abstract
Intrauterine environmental exposures have been shown to influence neonatal immunity and subsequent allergic disease development. We have previously shown that fewer lipopolysaccharide (LPS)-stimulated eosinophil-basophil (Eo/B) colonies grow from cord blood (CB) of high-atopic risk infants, compared to low-atopic risk infants. In the present study, we investigated whether a surrogate ex vivo TH2 milieu (i.e., either IL-4 or IL-13) could represent an underlying mechanism to explain our previous findings. CB CD34+ cells from healthy donors were cultured with IL-4 or IL-13 (in combination with LPS) and assessed for Eo/B differentiation using methylcellulose cultures and flow cytometry for related intracellular signalling pathways. Pharmacological inhibitors were added to the methylcellulose cultures to determine the effect of blocking intracellular signalling in CB CD34+ cells in relation to Eo/B colony forming unit (CFU) formation. Stimulation of CD34+ cells with IL-4, but not IL-13, reduced Eo/B CFU formation in the presence of LPS; this was found to be dependent on IL-4Rα and not IL-13Rα1. Additionally, IL-4 reduced the expression of ERK 1/2 after LPS stimulation, which was recovered by inhibition of IL-4Rα. While IL-13 did not have an inhibitory effect on ERK 1/2 expression, inhibition of ERK 1/2 significantly reduced Eo/B CFU formation. Thus, the responsiveness of CB CD34+ progenitor cells to LPS is differentially regulated by the TH2 cytokines, IL-4 and IL-13. This may have implications for in utero interactions between placental-derived pro-allergic cytokines and neonatal progenitor cells influencing Eo/B-mediated inflammatory responses in early life.
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16
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Gao M, Zhao D, Schouteden S, Sorci-Thomas MG, Van Veldhoven PP, Eggermont K, Liu G, Verfaillie CM, Feng Y. Regulation of high-density lipoprotein on hematopoietic stem/progenitor cells in atherosclerosis requires scavenger receptor type BI expression. Arterioscler Thromb Vasc Biol 2014; 34:1900-9. [PMID: 24969774 DOI: 10.1161/atvbaha.114.304006] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
OBJECTIVE Recently, we demonstrated that scavenger receptor type BI (SR-BI), a high-density lipoprotein (HDL) receptor, was expressed on murine hematopoietic stem/progenitor cells (HSPC) and infusion of reconstituted HDL and purified human apolipoprotein A-I (apoA-I) suppressed HSPC proliferation. We hypothesized that SR-B1 expression is required for the observed antiproliferative effects of HDL on HSPC. APPROACH AND RESULTS SR-BI-deficient (SR-BI(-/-)) mice and wild-type controls were fed on chow or high-fat diet (HFD) for 8 to 10 weeks. Under chow diet, a significant increase in Lin(-) Sca1(+) cKit(+) cells (LSK cells, so-called HSPC) was found in the bone marrow of SR-BI(-/-) mice when compared with wild-type mice. HFD induced a further expansion of CD150(+)CD48(-) LSK cells (HSC), HSPC, and granulocyte monocyte progenitors in SR-BI(-/-) mice. Injection of reactive oxygen species inhibitor N-acetylcysteine attenuated HFD-induced HSPC expansion, leukocytosis, and atherosclerosis in SR-BI(-/-) mice. ApoA-I infusion inhibited HSPC cell proliferation, Akt phosphorylation and reactive oxygen species production in HSPC and plaque progression in low-density lipoprotein receptor knockout (LDLr(-/-)) apoA-I(-/-) mice on HFD but had no effect on SR-BI(-/-) mice on HFD. Transplantation of SR-BI(-/-) bone marrow cells into irradiated LDLr(-/-) recipients resulted in enhanced white blood cells reconstitution, inflammatory cell production, and plaque development. In patients with coronary heart disease, HDL levels were negatively correlated with white blood cells count and HSPC frequency in the peripheral blood. By flow cytometry, SR-BI expression was detected on human HSPC. CONCLUSIONS SR-BI plays a critical role in the HDL-mediated regulation HSPC proliferation and differentiation, which is associated with atherosclerosis progression.
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Affiliation(s)
- Mingming Gao
- From the Institute of Cardiovascular Sciences and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University, Beijing, China (M.G., G.L.); Beijing Key Laboratory of Diabetes Research and Care, LuHe Hospital, Capital University, Peking, China (D.Z.); Interdepartmental Stem Cell Institute (S.S., K.E., C.M.V., Y.F.) and Laboratory of Lipid Biochemistry and Protein Interactions, Department of Cellular and Molecular Medicine (P.P.V.V.), Katholieke Universiteit Leuven, Leuven, Belgium; and Section on Molecular Medicine, Department of Medicine, Wake Forest University School of Medicine, Winston-Salem, NC (M.G.S.-T.)
| | - Dong Zhao
- From the Institute of Cardiovascular Sciences and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University, Beijing, China (M.G., G.L.); Beijing Key Laboratory of Diabetes Research and Care, LuHe Hospital, Capital University, Peking, China (D.Z.); Interdepartmental Stem Cell Institute (S.S., K.E., C.M.V., Y.F.) and Laboratory of Lipid Biochemistry and Protein Interactions, Department of Cellular and Molecular Medicine (P.P.V.V.), Katholieke Universiteit Leuven, Leuven, Belgium; and Section on Molecular Medicine, Department of Medicine, Wake Forest University School of Medicine, Winston-Salem, NC (M.G.S.-T.)
| | - Sarah Schouteden
- From the Institute of Cardiovascular Sciences and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University, Beijing, China (M.G., G.L.); Beijing Key Laboratory of Diabetes Research and Care, LuHe Hospital, Capital University, Peking, China (D.Z.); Interdepartmental Stem Cell Institute (S.S., K.E., C.M.V., Y.F.) and Laboratory of Lipid Biochemistry and Protein Interactions, Department of Cellular and Molecular Medicine (P.P.V.V.), Katholieke Universiteit Leuven, Leuven, Belgium; and Section on Molecular Medicine, Department of Medicine, Wake Forest University School of Medicine, Winston-Salem, NC (M.G.S.-T.)
| | - Mary G Sorci-Thomas
- From the Institute of Cardiovascular Sciences and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University, Beijing, China (M.G., G.L.); Beijing Key Laboratory of Diabetes Research and Care, LuHe Hospital, Capital University, Peking, China (D.Z.); Interdepartmental Stem Cell Institute (S.S., K.E., C.M.V., Y.F.) and Laboratory of Lipid Biochemistry and Protein Interactions, Department of Cellular and Molecular Medicine (P.P.V.V.), Katholieke Universiteit Leuven, Leuven, Belgium; and Section on Molecular Medicine, Department of Medicine, Wake Forest University School of Medicine, Winston-Salem, NC (M.G.S.-T.)
| | - Paul P Van Veldhoven
- From the Institute of Cardiovascular Sciences and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University, Beijing, China (M.G., G.L.); Beijing Key Laboratory of Diabetes Research and Care, LuHe Hospital, Capital University, Peking, China (D.Z.); Interdepartmental Stem Cell Institute (S.S., K.E., C.M.V., Y.F.) and Laboratory of Lipid Biochemistry and Protein Interactions, Department of Cellular and Molecular Medicine (P.P.V.V.), Katholieke Universiteit Leuven, Leuven, Belgium; and Section on Molecular Medicine, Department of Medicine, Wake Forest University School of Medicine, Winston-Salem, NC (M.G.S.-T.)
| | - Kristel Eggermont
- From the Institute of Cardiovascular Sciences and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University, Beijing, China (M.G., G.L.); Beijing Key Laboratory of Diabetes Research and Care, LuHe Hospital, Capital University, Peking, China (D.Z.); Interdepartmental Stem Cell Institute (S.S., K.E., C.M.V., Y.F.) and Laboratory of Lipid Biochemistry and Protein Interactions, Department of Cellular and Molecular Medicine (P.P.V.V.), Katholieke Universiteit Leuven, Leuven, Belgium; and Section on Molecular Medicine, Department of Medicine, Wake Forest University School of Medicine, Winston-Salem, NC (M.G.S.-T.)
| | - George Liu
- From the Institute of Cardiovascular Sciences and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University, Beijing, China (M.G., G.L.); Beijing Key Laboratory of Diabetes Research and Care, LuHe Hospital, Capital University, Peking, China (D.Z.); Interdepartmental Stem Cell Institute (S.S., K.E., C.M.V., Y.F.) and Laboratory of Lipid Biochemistry and Protein Interactions, Department of Cellular and Molecular Medicine (P.P.V.V.), Katholieke Universiteit Leuven, Leuven, Belgium; and Section on Molecular Medicine, Department of Medicine, Wake Forest University School of Medicine, Winston-Salem, NC (M.G.S.-T.)
| | - Catherine M Verfaillie
- From the Institute of Cardiovascular Sciences and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University, Beijing, China (M.G., G.L.); Beijing Key Laboratory of Diabetes Research and Care, LuHe Hospital, Capital University, Peking, China (D.Z.); Interdepartmental Stem Cell Institute (S.S., K.E., C.M.V., Y.F.) and Laboratory of Lipid Biochemistry and Protein Interactions, Department of Cellular and Molecular Medicine (P.P.V.V.), Katholieke Universiteit Leuven, Leuven, Belgium; and Section on Molecular Medicine, Department of Medicine, Wake Forest University School of Medicine, Winston-Salem, NC (M.G.S.-T.)
| | - Yingmei Feng
- From the Institute of Cardiovascular Sciences and Key Laboratory of Molecular Cardiovascular Sciences, Ministry of Education, Peking University, Beijing, China (M.G., G.L.); Beijing Key Laboratory of Diabetes Research and Care, LuHe Hospital, Capital University, Peking, China (D.Z.); Interdepartmental Stem Cell Institute (S.S., K.E., C.M.V., Y.F.) and Laboratory of Lipid Biochemistry and Protein Interactions, Department of Cellular and Molecular Medicine (P.P.V.V.), Katholieke Universiteit Leuven, Leuven, Belgium; and Section on Molecular Medicine, Department of Medicine, Wake Forest University School of Medicine, Winston-Salem, NC (M.G.S.-T.).
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17
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BMP signaling balances murine myeloid potential through SMAD-independent p38MAPK and NOTCH pathways. Blood 2014; 124:393-402. [PMID: 24894772 DOI: 10.1182/blood-2014-02-556993] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Bone morphogenetic protein (BMP) signaling regulates early hematopoietic development, proceeding from mesoderm patterning through the progressive commitment and differentiation of progenitor cells. The BMP pathway signals largely through receptor-mediated activation of Mothers Against Decapentaplegic homolog (SMAD) proteins, although alternate pathways are modulated through various components of mitogen-activated protein kinase (MAPK) signaling. Using a conditional, short hairpin RNA (shRNA)-based knockdown system in the context of differentiating embryonic stem cells (ESCs), we demonstrated previously that Smad1 promotes hemangioblast specification, but then subsequently restricts primitive progenitor potential. Here we show that co-knockdown of Smad5 restores normal progenitor potential of Smad1-depleted cells, suggesting opposing functions for Smad1 and Smad5. This balance was confirmed by cotargeting Smad1/5 with a specific chemical antagonist, LDN193189 (LDN). However, we discovered that LDN treatment after hemangioblast commitment enhanced primitive myeloid potential. Moreover, inhibition with LDN (but not SMAD depletion) increased expression of Delta-like ligands Dll1 and Dll3 and NOTCH activity; abrogation of NOTCH activity restored LDN-enhanced myeloid potential back to normal, corresponding with expression levels of the myeloid master regulator, C/EBPα. LDN but not SMAD activity was also associated with activation of the p38MAPK pathway, and blocking this pathway was sufficient to enhance myelopoiesis. Therefore, NOTCH and p38MAPK pathways balance primitive myeloid progenitor output downstream of the BMP pathway.
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18
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Abstract
Eosinophil differentiation is a complex series of events regulated by cytokines at multiple levels, including proliferation, survival, and maturation. The development of an ex vivo eosinophil differentiation model, using the current knowledge on factors involved in this process, has facilitated efforts to understand the molecular mechanisms underlying human eosinophil development. Differentiation of human hematopoietic progenitor cells, isolated by density centrifugation and immunomagnetic cell separation, towards mature eosinophils, involves a 17-day culture period in the presence of a mixture of cytokines. At early stages of differentiation, these cells can be retrovirally transduced resulting in modulation of the expression of genes of interest to examine their role in eosinophil development. Eosinophil maturation can be analyzed by combining three different methods: histochemical analysis, flow cytometric analysis, and Luxol Fast Blue staining. In addition to this ex vivo differentiation model, human hematopoietic progenitors can be transplanted into immune-deficient mice resulting in the development of all human hematopoietic lineages in the mouse bone marrow, including eosinophils. Although the ex vivo differentiation model can be used separately, combining it with the transplantation model will give insight into not only regulation of human eosinophil development but also hematopoiesis in general.
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Affiliation(s)
- Miranda Buitenhuis
- Department of Hematology, Erasmus MC, Dr. Molewaterplein 50, Rotterdam, The Netherlands,
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19
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Reece P, Baatjes AJ, Cyr MM, Sehmi R, Denburg JA. Toll-like receptor-mediated eosinophil-basophil differentiation: autocrine signalling by granulocyte-macrophage colony-stimulating factor in cord blood haematopoietic progenitors. Immunology 2013; 139:256-64. [PMID: 23347362 DOI: 10.1111/imm.12078] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Revised: 01/10/2013] [Accepted: 01/17/2013] [Indexed: 12/30/2022] Open
Abstract
Eosinophils are multi-functional leucocytes that play a role in inflammatory processes including allergy and infection. Although bone marrow (BM) inflammatory cells are the main source of eosinophil-basophil (Eo/B) differentiation-inducing cytokines, a recent role has been demonstrated for cytokine induction through Toll-like receptor (TLR)-mediated signalling in BM progenitors. Having previously demonstrated that cord blood (CB) progenitors induce Eo/B colony-forming units (CFU) after lipopolysaccharide (LPS) stimulation, we sought to investigate the intracellular mechanisms by which LPS induces Eo/B differentiation. Freshly isolated CD34-enriched human CB cells were stimulated with LPS (and/or pharmacological inhibitors) and assessed for alterations in haematopoietic cytokine receptor expression and signalling pathways by flow cytometry, Eo/B CFU in methylcellulose cultures, and cytokine secretion using Luminex assays. The LPS stimulation resulted in a significant increase in granulocyte-macrophage colony-stimulating factor (GM-CSF)-responsive, as opposed to interleukin-5-responsive, Eo/B CFU, which also correlated with significant increases in CD34(+) cell GM-CSFRα expression. Functionally, CB CD34(+) cells secrete abundant amounts of GM-CSF following LPS stimulation, via a p38 mitogen-activated protein kinase (MAPK)-dependent mechanism; this secretion was responsible for Eo/B CFU formation ex vivo, as shown by antibody blockade. We show for the first time that LPS stimulation of CB progenitor cells results in autocrine activation of p38 MAPK-dependent GM-CSF secretion facilitating Eo/B differentiation ex vivo. This work provides evidence that early life exposure to products of bacterial agents can modulate Eo/B differentiation, representing a novel mechanism by which progenitor cells can respond to microbial stimuli and so affect immune and inflammatory responses.
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Affiliation(s)
- Pia Reece
- Division of Clinical Immunology and Allergy, McMaster University, Hamilton, ON, Canada
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20
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Pharmacological inhibition of p38 mitogen-activated protein kinases affects KC/CXCL1-induced intraluminal crawling, transendothelial migration, and chemotaxis of neutrophils in vivo. Mediators Inflamm 2013; 2013:290565. [PMID: 23533303 PMCID: PMC3603207 DOI: 10.1155/2013/290565] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Revised: 01/15/2013] [Accepted: 01/29/2013] [Indexed: 01/26/2023] Open
Abstract
p38 mitogen-activated protein kinase (MAPK) signalling is critical in the pathophysiology of a variety of inflammatory processes. Leukocyte recruitment to the site of inflammation is a multistep process governed by specific signalling cascades. After adhesion in the lumen, many leukocytes crawl to optimal sites at endothelial junctions and transmigrate to extravascular tissue in a Mac-1-dependent manner. The signalling mechanisms that regulate postadhesion steps of intraluminal crawling, transmigration, and chemotaxis in tissue remain incompletely understood. The present study explored the effect of p38 MAPK inhibitor SB203580 on various parameters of neutrophil recruitment triggered by chemokine KC (CXCL1) gradient. Neutrophil-endothelial interactions in microvasculature of murine cremaster muscle were determined using intravital microscopy and time-lapsed video analysis. SB203580 (100 nM) did not change leukocyte rolling but significantly attenuated neutrophil adhesion, emigration, and transmigration and impaired the initiation of neutrophil crawling and transmigration. In response to KC chemotactic gradient, SB203580 significantly reduced the velocity of migration and chemotaxis index of neutrophils in tissue. The upregulation of Mac-1 expression in neutrophils stimulated by KC was significantly blunted by SB203580 in vitro. Collectively, our findings demonstrate that pharmacological suppression of p38 MAPK significantly impairs multiple steps of neutrophil recruitment in vivo.
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21
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Sato A, Yamada N, Ogawa Y, Ikegami M. CCAAT/enhancer-binding protein-α suppresses lung tumor development in mice through the p38α MAP kinase pathway. PLoS One 2013; 8:e57013. [PMID: 23437297 PMCID: PMC3577786 DOI: 10.1371/journal.pone.0057013] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Accepted: 01/16/2013] [Indexed: 01/02/2023] Open
Abstract
The transcription factor CCAAT/enhancer-binding protein α (C/EBPα) is a basic leucine zipper transcription factor and is expressed in alveolar type II cells, alveolar macrophages and Clara cells in the lung. Although decrease or absence of C/EBPα expression in human non-small cell lung cancer suggests a possible role of C/EBPα as a lung tumor suppressor, there is no direct proof for this hypothesis. In this study, we investigated, for the first time, the role of C/EBPα in lung tumors in vivo using transgenic mice with lung epithelial specific conditional deletion of Cebpa (Cebpα(Δ/Δ) mice) and a urethane-induced lung tumor model. C/EBPα expression in the lung was dispensable, and its deletion was not oncogenic under unstressed conditions. However, at 28 wk after urethane injection, the number and size of tumors and the tumor burden were significantly higher in Cebpα(Δ/Δ) mice than in littermate control mice. Urethane-injected Cebpα(Δ/Δ) mice showed highly proliferative adenomas and adenocarcinomas in the lung, and survival time after urethane-injection was significantly shorter than that in control mice. In control mice, C/EBPα was strongly induced in the tumor tissues at 28 weeks after urethane-injection, but became weakened or absent as tumors progressed after long-term observation for over 1 year. Using intraperitoneal injection of p38 inhibitor (SB203580), we demonstrated that the induction of C/EBPα is strongly regulated by the p38 MAP kinase in murine alveolar epithelial cells. A high correlation was demonstrated between the expression of C/EBPα and p38α MAP kinase in tumor cells, suggesting that C/EBPα silencing in tumor cells is caused by down-regulation of p38α MAP kinase. In conclusion, the role of C/EBPα as a lung tumor suppressor was demonstrated for the first time in the present study, and the extinguished C/EBPα expression through p38α inactivation leads tumor promotion and progression.
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Affiliation(s)
- Atsuyasu Sato
- Division of Pulmonary Biology, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, United States of America
| | - Norishige Yamada
- Division of Reproductive Sciences, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, United States of America
| | - Yuya Ogawa
- Division of Reproductive Sciences, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, United States of America
| | - Machiko Ikegami
- Division of Pulmonary Biology, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, United States of America
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22
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Abstract
Neutrophils are critically involved in host defense and tissue damage. Intrinsic molecular mechanisms controlling neutrophil differentiation and activities are poorly defined. Herein we found that p53-induced phosphatase 1(Wip1) is preferentially expressed in neutrophils among immune cells. The Wip1 expression is gradually up-regulated during the differentiation of myeloid precursors into mature neutrophils. Wip1-deficient mice and chimera mice with Wip1(-/-) hematopoietic cells had an expanded pool of neutrophils with hypermature phenotypes in the periphery. The in vivo and in vitro studies showed that Wip1 deficiency mainly impaired the developing process of myeloid progenitors to neutrophils in an intrinsic manner. Mechanism studies showed that the enhanced development and maturation of neutrophils caused by Wip1 deficiency were mediated by p38 MAPK-STAT1 but not p53-dependent pathways. Thus, our findings identify a previously unrecognized p53-independent function of Wip1 as a cell type-specific negative regulator of neutrophil generation and homeostasis through limiting the p38 MAPK-STAT1 pathway.
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23
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Yang SH, Sharrocks AD, Whitmarsh AJ. MAP kinase signalling cascades and transcriptional regulation. Gene 2012; 513:1-13. [PMID: 23123731 DOI: 10.1016/j.gene.2012.10.033] [Citation(s) in RCA: 313] [Impact Index Per Article: 26.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2012] [Revised: 10/08/2012] [Accepted: 10/18/2012] [Indexed: 02/06/2023]
Abstract
The MAP kinase (MAPK) signalling pathways play fundamental roles in a wide range of cellular processes and are often deregulated in disease states. One major mode of action for these pathways is in controlling gene expression, in particular through regulating transcription. In this review, we discuss recent significant advances in this area. In particular we focus on the mechanisms by which MAPKs are targeted to the nucleus and chromatin, and once there, how they impact on chromatin structure and subsequent gene regulation. We also discuss how systems biology approaches have contributed to our understanding of MAPK signaling networks, and also how the MAPK pathways intersect with other regulatory pathways in the nucleus. Finally, we summarise progress in studying the physiological functions of key MAPK transcriptional targets.
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Affiliation(s)
- Shen-Hsi Yang
- Faculty of Life Sciences, University of Manchester, Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK
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24
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Fragliasso V, Chiodo Y, Ferrari-Amorotti G, Soliera AR, Manzotti G, Cattelani S, Candini O, Grisendi G, Vergalli J, Mariani SA, Guerzoni C, Calabretta B. Phosphorylation of serine 21 modulates the proliferation inhibitory more than the differentiation inducing effects of C/EBPα in K562 cells. J Cell Biochem 2012; 113:1704-13. [PMID: 22212957 DOI: 10.1002/jcb.24040] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The CCAAT/enhancer binding protein α (C/EBPα) is a transcription factor required for differentiation of myeloid progenitors. In acute myeloid leukemia (AML) cells expressing the constitutively active FLT3-ITD receptor tyrosine kinase, MAP kinase-dependent phosphorylation of serine 21 (S21) inhibits the ability of C/EBPα to induce granulocytic differentiation. To assess whether this post-translational modification also modulates the activity of C/EBPα in BCR/ABL-expressing cells, we tested the biological effects of wild-type and mutant C/EBPα mimicking phosphorylated or non-phosphorylatable serine 21 (S21D and S21A, respectively) in K562 cells ectopically expressing tamoxifen-regulated C/EBPα-ER chimeric proteins. We show here that S21D C/EBPα-ER induced terminal granulocytic differentiation of K562 cells almost as well as wild-type C/EBPα-ER, while S21A C/EBPα-ER was less efficient. Furthermore, wild-type C/EBPα suppressed the proliferation and colony formation of K562 cells vigorously, while S21D and S21A C/EBPα mutants had more modest anti-proliferative effects. Both mutants were less effective than wild-type C/EBPα in suppressing endogenous E2F-dependent transactivation and bound less E2F-2 and/or E2F-3 proteins in anti-C/EBPα immunoprecipitates. Together, these findings suggest that mutation of S21 more than its phosphorylation inhibits the anti-proliferative effects of C/EBPα due to reduced interaction with or impaired regulation of the activity of E2F proteins. By contrast, phosphorylation of serine 21 appears to have a modest role in modulating the differentiation-inducing effects of C/EBPα in K562 cells.
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Affiliation(s)
- Valentina Fragliasso
- Department of Biomedical Sciences, University of Modena and Reggio Emilia, Modena, Italy
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25
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Radomska HS, Alberich-Jordà M, Will B, Gonzalez D, Delwel R, Tenen DG. Targeting CDK1 promotes FLT3-activated acute myeloid leukemia differentiation through C/EBPα. J Clin Invest 2012; 122:2955-66. [PMID: 22797303 DOI: 10.1172/jci43354] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2010] [Accepted: 06/07/2012] [Indexed: 11/17/2022] Open
Abstract
Mutations that activate the fms-like tyrosine kinase 3 (FLT3) receptor are among the most prevalent mutations in acute myeloid leukemias. The oncogenic role of FLT3 mutants has been attributed to the abnormal activation of several downstream signaling pathways, such as STAT3, STAT5, ERK1/2, and AKT. Here, we discovered that the cyclin-dependent kinase 1 (CDK1) pathway is also affected by internal tandem duplication mutations in FLT3. Moreover, we also identified C/EBPα, a granulopoiesis-promoting transcription factor, as a substrate for CDK1. We further demonstrated that CDK1 phosphorylates C/EBPα on serine 21, which inhibits its differentiation-inducing function. Importantly, we found that inhibition of CDK1 activity relieves the differentiation block in cell lines with mutated FLT3 as well as in primary patient-derived peripheral blood samples. Clinical trials with CDK1 inhibitors are currently under way for various malignancies. Our data strongly suggest that targeting the CDK1 pathway might be applied in the treatment of FLT3ITD mutant leukemias, especially those resistant to FLT3 inhibitor therapies.
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Affiliation(s)
- Hanna S Radomska
- Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA, USA
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The many faces of p38 mitogen-activated protein kinase in progenitor/stem cell differentiation. Biochem J 2012; 445:1-10. [DOI: 10.1042/bj20120401] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Regulation of stem cells is essential for development and adult tissue homoeostasis. The proper control of stem cell self-renewal and differentiation maintains organ physiology, and disruption of such a balance results in disease. There are many mechanisms that have been established as stem cell regulators, such as Wnt or Notch signals. However, the intracellular mechanisms that mediate and integrate these signals are not well understood. A new intracellular pathway that has been reported to be involved in the regulation of many stem cell types is that of p38 MAPK (mitogen-activated protein kinase). In particular, p38α is essential for the proper differentiation of many haematopoietic, mesenchymal and epithelial stem/progenitor cells. Many reports have shown that disruption of this kinase pathway has pathological consequences in many organs. Understanding the extracellular cues and downstream targets of p38α in stem cell regulation may help to tackle some of the pathologies associated with improper differentiation and regulation of stem cell function. In the present review we present a vision of the current knowledge on the roles of the p38α signal as a regulator of stem/progenitor cells in different tissues in physiology and disease.
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Koleva RI, Ficarro SB, Radomska HS, Carrasco-Alfonso MJ, Alberta JA, Webber JT, Luckey CJ, Marcucci G, Tenen DG, Marto JA. C/EBPα and DEK coordinately regulate myeloid differentiation. Blood 2012; 119:4878-88. [PMID: 22474248 PMCID: PMC3367892 DOI: 10.1182/blood-2011-10-383083] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Accepted: 03/10/2012] [Indexed: 11/20/2022] Open
Abstract
The transcription factor C/EBPα is a critical mediator of myeloid differentiation and is often functionally impaired in acute myeloid leukemia. Recent studies have suggested that oncogenic FLT3 activity disrupts wild-type C/EBPα function via phosphorylation on serine 21 (S21). Despite the apparent role of pS21 as a negative regulator of C/EBPα transcription activity, the mechanism by which phosphorylation tips the balance between transcriptionally competent and inhibited forms remains unresolved. In the present study, we used immuno-affinity purification combined with quantitative mass spectrometry to delineate the proteins associated with C/EBPα on chromatin. We identified DEK, a protein with genetic links to leukemia, as a member of the C/EBPα complexes, and demonstrate that this association is disrupted by S21 phosphorylation. We confirmed that DEK is recruited specifically to chromatin with C/EBPα to enhance GCSFR3 promoter activation. In addition, we demonstrated that genetic depletion of DEK reduces the ability of C/EBPα to drive the expression of granulocytic target genes in vitro and disrupts G-CSF-mediated granulocytic differentiation of fresh human BM-derived CD34(+) cells. Our data suggest that C/EBPα and DEK coordinately activate myeloid gene expression and that S21 phosphorylation on wild-type C/EBPα mediates protein interactions that regulate the differentiation capacity of hematopoietic progenitors.
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Affiliation(s)
- Rositsa I Koleva
- Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA 02215-5450, USA
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Park K, Elias PM, Oda Y, Mackenzie D, Mauro T, Holleran WM, Uchida Y. Regulation of cathelicidin antimicrobial peptide expression by an endoplasmic reticulum (ER) stress signaling, vitamin D receptor-independent pathway. J Biol Chem 2011; 286:34121-30. [PMID: 21832078 DOI: 10.1074/jbc.m111.250431] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Vitamin D receptor (VDR)-dependent mechanisms regulate human cathelicidin antimicrobial peptide (CAMP)/LL-37 in various cell types, but CAMP expression also increases after external perturbations (such as infection, injuries, UV irradiation, and permeability barrier disruption) in parallel with induction of endoplasmic reticulum (ER) stress. We demonstrate that CAMP mRNA and protein expression increase in epithelial cells (human primary keratinocytes, HaCaT keratinocytes, and HeLa cells), but not in myeloid (U937 and HL-60) cells, following ER stress generated by two mechanistically different, pharmacological stressors, thapsigargin or tunicamycin. The mechanism for increased CAMP following exposure to ER stress involves NF-κB activation leading to CCAAT/enhancer-binding protein α (C/EBPα) activation via MAP kinase-mediated phosphorylation. Furthermore, both increased CAMP secretion and its proteolytic processing to LL-37 are required for antimicrobial activities occur following ER stress. In addition, topical thapsigargin also increases production of the murine homologue of CAMP in mouse epidermis. Finally and paradoxically, ER stress instead suppresses the 1,25(OH)(2) vitamin D(3)-induced activation of VDR, but blockade of VDR activity does not alter ER stress-induced CAMP up-regulation. Hence, ER stress increases CAMP expression via NF-κB-C/EBPα activation, independent of VDR, illuminating a novel VDR-independent role for ER stress in stimulating innate immunity.
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Affiliation(s)
- Kyungho Park
- Department of Dermatology, School of Medicine, University of California, San Francisco, California 94143, USA
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Duong V, Rochette-Egly C. The molecular physiology of nuclear retinoic acid receptors. From health to disease. Biochim Biophys Acta Mol Basis Dis 2011; 1812:1023-31. [DOI: 10.1016/j.bbadis.2010.10.007] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2010] [Accepted: 10/15/2010] [Indexed: 12/20/2022]
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Abstract
The p38 MAPK (mitogen-activated protein kinase) signalling pathway allows cells to interpret a wide range of external signals and respond appropriately by generating a plethora of different biological effects. The diversity and specificity in cellular outcomes is achieved with an apparently simple linear architecture of the pathway, consisting of a core of three protein kinases acting sequentially. In the present review, we dissect the molecular mechanisms underlying p38 MAPK functions, with special emphasis on the activation and regulation of the core kinases, the interplay with other signalling pathways and the nature of p38 MAPK substrates as a source of functional diversity. Finally, we discuss how genetic mouse models are facilitating the identification of physiological functions for p38 MAPKs, which may impinge on their eventual use as therapeutic targets.
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Ruela-de-Sousa RR, Queiroz KCS, Peppelenbosch MP, Fuhler GM. Reversible phosphorylation in haematological malignancies: potential role for protein tyrosine phosphatases in treatment? Biochim Biophys Acta Rev Cancer 2010; 1806:287-303. [PMID: 20659529 DOI: 10.1016/j.bbcan.2010.07.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2010] [Revised: 07/16/2010] [Accepted: 07/20/2010] [Indexed: 01/12/2023]
Abstract
Most aspects of leukocyte physiology are under the control of reversible tyrosine phosphorylation. It is clear that excessive phosphorylation of signal transduction elements is a pivotal element of many different pathologies including haematological malignancies and accordingly, strategies that target such phosphorylation have clinically been proven highly successful for treatment of multiple types of leukemias and lymphomas. Cellular phosphorylation status is dependent on the resultant activity of kinases and phosphatases. The cell biology of the former is now well understood; for most cellular phosphoproteins we now know the kinases responsible for their phosphorylation and we understand the principles of their aberrant activity in disease. With respect to phosphatases, however, our knowledge is much patchier. Although the sequences of whole genomes allow us to identify phosphatases using in silico methodology, whereas transcription profiling allows us to understand how phosphatase expression is regulated during disease, most functional questions as to substrate specificity, dynamic regulation of phosphatase activity and potential for therapeutic intervention are still to a large degree open. Nevertheless, recent studies have allowed us to make meaningful statements on the role of tyrosine phosphatase activity in the three major signaling pathways that are commonly affected in leukemias, i.e. the Ras-Raf-ERK1/2, the Jak-STAT and the PI3K-PKB-mTOR pathways. Lessons learned from these pathways may well be applicable elsewhere in leukocyte biology as well.
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Affiliation(s)
- Roberta R Ruela-de-Sousa
- Center for Experimental and Molecular Medicine, Academic Medical Center, Meibergdreef 9 1105 AZ Amsterdam, The Netherlands
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