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Wei Y, Li W. Calcium, an Emerging Intracellular Messenger for the Hippo Pathway Regulation. Front Cell Dev Biol 2021; 9:694828. [PMID: 34268313 PMCID: PMC8275986 DOI: 10.3389/fcell.2021.694828] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 06/09/2021] [Indexed: 12/22/2022] Open
Abstract
The Hippo pathway is a conserved signaling network regulating organ development and tissue homeostasis. Dysfunction of this pathway may lead to various diseases, such as regeneration defect and cancer. Studies over the past decade have found various extracellular and intracellular signals that can regulate this pathway. Among them, calcium (Ca2+) is emerging as a potential messenger that can transduce certain signals, such as the mechanical cue, to the main signaling machinery. In this process, rearrangement of the actin cytoskeleton, such as calcium-activated actin reset (CaAR), may construct actin filaments at the cell cortex or other subcellular domains that provide a scaffold to launch Hippo pathway activators. This article will review studies demonstrating Ca2+-mediated Hippo pathway modulation and discuss its implication in understanding the role of actin cytoskeleton in regulating the Hippo pathway.
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Affiliation(s)
- Yiju Wei
- Division of Hematology and Oncology, Department of Pediatrics, Penn State College of Medicine, Hershey, PA, United States
| | - Wei Li
- Division of Hematology and Oncology, Department of Pediatrics, Penn State College of Medicine, Hershey, PA, United States.,Department of Biochemistry and Molecular Biology, Penn State College of Medicine, Hershey, PA, United States
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2
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Xue T, Li C, Zhang H, Han Y, Wu J. Effects of Aster B-mediated intracellular accumulation of cholesterol on inflammatory process and myocardial cells in acute myocardial infarction. Hellenic J Cardiol 2021; 63:32-39. [PMID: 34147675 DOI: 10.1016/j.hjc.2021.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 06/07/2021] [Accepted: 06/08/2021] [Indexed: 11/04/2022] Open
Abstract
BACKGROUND To investigate the effect of cholesterol accumulation in cells on the inflammatory process of acute myocardial infarction and cardiomyocytes and its mechanism. METHODS Blood samples of 15 patients with myocardial infarction were clinically collected to detect enzyme levels of cholesterol and related myocardial parameters in the serum. Correlation analysis was carried out. At the cellular level, simulation of cholesterol entry and exit from cells was conducted by a liposome-loaded cholesterol model in this study, and BNP and inflammatory factors were detected with enzyme-linked immunosorbent assay. Moreover, to investigate the molecular mechanism of myocardial damage caused by cholesterol, Gramd1b and Prkaca of HL-1 were knocked down with small interference RNA technique. Then, inhibitor C3 was used to weaken RhoA activity to explore the level of cardiac muscle cell BNP in order to identify key protein target sites that may be involved in the process of cholesterol damage to cardiac muscle cells. RESULTS Serum cholesterol concentration showed a significantly positive correlation with the levels of AST, CK, and LD in serum of patients with myocardial infarction. Cholesterol accumulation in cardiac muscle cells significantly increased the levels of BNP, inflammatory factors (IL-1β, IL-6, TNF-α, and CCL-2) in cardiac muscle cells, which exacerbated cardiomyocyte damage. Conversely, cholesterol excretion caused significant downregulation of BNP and inflammatory factors. Moreover, after knocking down Gramd1b, the accumulation of cholesterol in myocardial cells decreased, the levels of BNP and inflammatory factors significantly reduced, and the degree of myocardial cell damage was weakened. Knockdown of Prkaca inhibited RhoA activity and reversed cholesterol-induced elevation of BNP and inflammatory factors. CONCLUSION ASTER B-mediated intracellular accumulation of cholesterol in cardiac muscle cells may cause cardiomyocyte damage and inflammatory factor infiltration through PKA-Ca2+-RhoA pathways.
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Affiliation(s)
- Tan Xue
- Department of Cardiology, The Second Affiliated Hospital of Qiqihar Medical College, Qiqihar 161006, China
| | - Chunfeng Li
- Department of Cardiology, The Second Affiliated Hospital of Qiqihar Medical College, Qiqihar 161006, China
| | - Hongyan Zhang
- Department of Cardiology, The Second Affiliated Hospital of Qiqihar Medical College, Qiqihar 161006, China
| | - Yunfeng Han
- Department of Epidemiology and Health Statistics, Public Health, Qiqihar Medical University, Qiqihar 161006, China
| | - Jiahui Wu
- Department of Environment and Occupational Health, School of Public Health, Qiqihar Medical University, Qiqihar 161006, China.
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Wang X, Cai B, Yang X, Sonubi OO, Zheng Z, Ramakrishnan R, Shi H, Valenti L, Pajvani UB, Sandhu J, Infante RE, Radhakrishnan A, Covey DF, Guan KL, Buck J, Levin LR, Tontonoz P, Schwabe RF, Tabas I. Cholesterol Stabilizes TAZ in Hepatocytes to Promote Experimental Non-alcoholic Steatohepatitis. Cell Metab 2020; 31:969-986.e7. [PMID: 32259482 PMCID: PMC7313619 DOI: 10.1016/j.cmet.2020.03.010] [Citation(s) in RCA: 100] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Revised: 01/04/2020] [Accepted: 03/11/2020] [Indexed: 12/15/2022]
Abstract
Incomplete understanding of how hepatosteatosis transitions to fibrotic non-alcoholic steatohepatitis (NASH) has limited therapeutic options. Two molecules that are elevated in hepatocytes in human NASH liver are cholesterol, whose mechanistic link to NASH remains incompletely understood, and TAZ, a transcriptional regulator that promotes fibrosis but whose mechanism of increase in NASH is unknown. We now show that increased hepatocyte cholesterol upregulates TAZ and promotes fibrotic NASH. ASTER-B/C-mediated internalization of plasma membrane cholesterol activates soluble adenylyl cyclase (sAC; ADCY10), triggering a calcium-RhoA-mediated pathway that suppresses β-TrCP/proteasome-mediated TAZ degradation. In mice fed with a cholesterol-rich NASH-inducing diet, hepatocyte-specific silencing of ASTER-B/C, sAC, or RhoA decreased TAZ and ameliorated fibrotic NASH. The cholesterol-TAZ pathway is present in primary human hepatocytes, and associations among liver cholesterol, TAZ, and RhoA in human NASH liver are consistent with the pathway. Thus, hepatocyte cholesterol contributes to fibrotic NASH by increasing TAZ, suggesting new targets for therapeutic intervention.
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Affiliation(s)
- Xiaobo Wang
- Department of Medicine, Columbia University Irving Medical Center, New York, NY 10032, USA.
| | - Bishuang Cai
- Department of Medicine, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Xiaoming Yang
- Department of Pathophysiology, School of Basic Medical Sciences, Ningxia Medical University, Yinchuan, Ningxia 750004, PRC
| | - Oluwatoni O Sonubi
- Department of Pharmacology, Weill Cornell Medical College, New York, NY 10065, USA
| | - Ze Zheng
- Department of Medicine, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Rajasekhar Ramakrishnan
- Department of Pediatrics, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Hongxue Shi
- Department of Medicine, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Luca Valenti
- Department of Pathophysiology and Transplantation, Università degli Studi di Milano, Milano 20122, Italy; Translational Medicine - Transfusion Medicine and Hematology, Fondazione Ca' Granda IRCCS Ospedale Maggiore Policlinico, Milano 20122, Italy
| | - Utpal B Pajvani
- Department of Medicine, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Jaspreet Sandhu
- Department of Pathology and Laboratory Medicine, Molecular Biology Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90272, USA
| | - Rodney E Infante
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Arun Radhakrishnan
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Douglas F Covey
- Department of Developmental Biology and Taylor Family Institute for Innovative Psychiatric Research, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Kun-Liang Guan
- Department of Pharmacology and Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jochen Buck
- Department of Pharmacology, Weill Cornell Medical College, New York, NY 10065, USA
| | - Lonny R Levin
- Department of Pharmacology, Weill Cornell Medical College, New York, NY 10065, USA
| | - Peter Tontonoz
- Department of Pathology and Laboratory Medicine, Molecular Biology Institute, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90272, USA
| | - Robert F Schwabe
- Department of Medicine, Columbia University Irving Medical Center, New York, NY 10032, USA; Institute of Human Nutrition, Columbia University, New York, NY 10032, USA
| | - Ira Tabas
- Department of Medicine, Columbia University Irving Medical Center, New York, NY 10032, USA; Department of Physiology and Cellular Biophysics, Columbia University Irving Medical Center, New York, NY 10032, USA.
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Scheible N, McCubbin A. Signaling in Pollen Tube Growth: Beyond the Tip of the Polarity Iceberg. PLANTS (BASEL, SWITZERLAND) 2019; 8:E156. [PMID: 31181594 PMCID: PMC6630365 DOI: 10.3390/plants8060156] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 06/04/2019] [Accepted: 06/06/2019] [Indexed: 12/15/2022]
Abstract
The coordinated growth of pollen tubes through floral tissues to deliver the sperm cells to the egg and facilitate fertilization is a highly regulated process critical to the Angiosperm life cycle. Studies suggest that the concerted action of a variety of signaling pathways underlies the rapid polarized tip growth exhibited by pollen tubes. Ca2+ and small GTPase-mediated pathways have emerged as major players in the regulation of pollen tube growth. Evidence suggests that these two signaling pathways not only integrate with one another but also with a variety of other important signaling events. As we continue to elucidate the mechanisms involved in pollen tube growth, there is a growing importance in taking a holistic approach to studying these pathways in order to truly understand how tip growth in pollen tubes is orchestrated and maintained. This review considers our current state of knowledge of Ca2+-mediated and GTPase signaling pathways in pollen tubes, how they may intersect with one another, and other signaling pathways involved. There will be a particular focus on recent reports that have extended our understanding in these areas.
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Affiliation(s)
- Nolan Scheible
- School of Biological Sciences, Washington State University, Pullman, WA 99164-4236, USA.
| | - Andrew McCubbin
- School of Biological Sciences, Washington State University, Pullman, WA 99164-4236, USA.
- Center for Reproductive Biology, Pullman, WA, 99164, USA.
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Dekraker C, Boucher E, Mandato CA. Regulation and Assembly of Actomyosin Contractile Rings in Cytokinesis and Cell Repair. Anat Rec (Hoboken) 2018; 301:2051-2066. [PMID: 30312008 DOI: 10.1002/ar.23962] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Revised: 08/24/2018] [Accepted: 08/27/2018] [Indexed: 01/17/2023]
Abstract
Cytokinesis and single-cell wound repair both involve contractile assemblies of filamentous actin (F-actin) and myosin II organized into characteristic ring-like arrays. The assembly of these actomyosin contractile rings (CRs) is specified spatially and temporally by small Rho GTPases, which trigger local actin polymerization and myosin II contractility via a variety of downstream effectors. We now have a much clearer view of the Rho GTPase signaling cascade that leads to the formation of CRs, but some factors involved in CR positioning, assembly, and function remain poorly understood. Recent studies show that this regulation is multifactorial and goes beyond the long-established Ca2+ -dependent processes. There is substantial evidence that the Ca2+ -independent changes in cell shape, tension, and plasma membrane composition that characterize cytokinesis and single-cell wound repair also regulate CR formation. Elucidating the regulation and mechanistic properties of CRs is important to our understanding of basic cell biology and holds potential for therapeutic applications in human disease. In this review, we present a primer on the factors influencing and regulating CR positioning, assembly, and contraction as they occur in a variety of cytokinetic and single-cell wound repair models. Anat Rec, 301:2051-2066, 2018. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Corina Dekraker
- Department of Anatomy and Cell Biology, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
| | - Eric Boucher
- Department of Anatomy and Cell Biology, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
| | - Craig A Mandato
- Department of Anatomy and Cell Biology, Faculty of Medicine, McGill University, Montreal, Quebec, Canada
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He L, Tao J, Maity D, Si F, Wu Y, Wu T, Prasath V, Wirtz D, Sun SX. Role of membrane-tension gated Ca 2+ flux in cell mechanosensation. J Cell Sci 2018; 131:jcs208470. [PMID: 29361533 PMCID: PMC5868948 DOI: 10.1242/jcs.208470] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 01/12/2018] [Indexed: 01/10/2023] Open
Abstract
Eukaryotic cells are sensitive to mechanical forces they experience from the environment. The process of mechanosensation is complex, and involves elements such as the cytoskeleton and active contraction from myosin motors. Ultimately, mechanosensation is connected to changes in gene expression in the cell, known as mechanotransduction. While the involvement of the cytoskeleton in mechanosensation is known, the processes upstream of cytoskeletal changes are unclear. In this paper, by using a microfluidic device that mechanically compresses live cells, we demonstrate that Ca2+ currents and membrane tension-sensitive ion channels directly signal to the Rho GTPase and myosin contraction. In response to membrane tension changes, cells actively regulate cortical myosin contraction to balance external forces. The process is captured by a mechanochemical model where membrane tension, myosin contraction and the osmotic pressure difference between the cytoplasm and extracellular environment are connected by mechanical force balance. Finally, to complete the picture of mechanotransduction, we find that the tension-sensitive transcription factor YAP family of proteins translocate from the nucleus to the cytoplasm in response to mechanical compression.
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Affiliation(s)
- Lijuan He
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Jiaxiang Tao
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Debonil Maity
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA
- Physical Sciences in Oncology Center (PSOC), Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Fangwei Si
- Department of Physics, University of California San Diego, San Diego, CA 92010, USA
| | - Yi Wu
- Department of Cell Biology, University of Connecticut Health Center, Farmington, CT 06030, USA
| | - Tiffany Wu
- Department of Molecular and Cellular Biology, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Vishnu Prasath
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Denis Wirtz
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA
- Physical Sciences in Oncology Center (PSOC), Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Sean X Sun
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA
- Physical Sciences in Oncology Center (PSOC), Johns Hopkins University, Baltimore, Maryland 21218, USA
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Barjaktarovic Z, Merl-Pham J, Azimzadeh O, Kempf SJ, Raj K, Atkinson MJ, Tapio S. Low-dose radiation differentially regulates protein acetylation and histone deacetylase expression in human coronary artery endothelial cells. Int J Radiat Biol 2016; 93:156-164. [DOI: 10.1080/09553002.2017.1237059] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Zarko Barjaktarovic
- Institute of Radiation Biology, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Juliane Merl-Pham
- Research Unit Protein Science, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Omid Azimzadeh
- Institute of Radiation Biology, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Stefan J. Kempf
- Institute of Radiation Biology, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
| | - Ken Raj
- Biological Effects Department, Centre for Radiation, Chemicals and Environmental Hazards, Public Health England, Chilton, Oxfordshire, UK
| | - Michael J. Atkinson
- Institute of Radiation Biology, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
- Chair of Radiation Biology, Technical University Munich, Munich, Germany
| | - Soile Tapio
- Institute of Radiation Biology, Helmholtz Zentrum München, German Research Center for Environmental Health, Neuherberg, Germany
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Christodoulou N, Skourides P. Cell-Autonomous Ca 2+ Flashes Elicit Pulsed Contractions of an Apical Actin Network to Drive Apical Constriction during Neural Tube Closure. Cell Rep 2015; 13:2189-202. [DOI: 10.1016/j.celrep.2015.11.017] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Revised: 09/13/2015] [Accepted: 11/03/2015] [Indexed: 01/08/2023] Open
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Li Q, Chen B, Zeng C, Fan A, Yuan Y, Guo X, Huang X, Huang Q. Differential activation of receptors and signal pathways upon stimulation by different doses of sphingosine-1-phosphate in endothelial cells. Exp Physiol 2014; 100:95-107. [PMID: 25557733 DOI: 10.1113/expphysiol.2014.082149] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Accepted: 10/21/2014] [Indexed: 01/08/2023]
Abstract
NEW FINDINGS What is the central question of this study? Why do different doses of sphingosine-1-phosphate (S1P) induce distinct biological effects in endothelial cells? What is the main finding and its importance? S1P at physiological concentrations preserved endothelial barrier function by binding to S1P receptor 1, then triggering Ca(2+) release from endoplasmic reticulum through phosphoinositide phospholipase C and inositol triphosphate, and consequently strengthening tight junction and F-actin assembly through Rac1 activation. Excessive S1P induced endothelial malfunction by activating S1P receptor 2 and RhoA/ROCK pathway, causing F-actin and tight junction disorganisation. Extracellular Ca(2+) influx was involved in this process. Sphingosine-1-phosphate (S1P) is a bioactive sphingolipid in plasma, and its plasma concentration can be adjusted through a complex metabolic process. The alterations in S1P levels and the activation of receptors collaboratively regulate distinct biological effects. This study was performed to investigate comparatively the effect of different concentrations of S1P on endothelial barrier function and to explore the roles of S1P receptors (S1PRs), Rho GTPases and calcium in S1P-induced endothelial responses. Endothelial barrier function was studied using transendothelial electric resistance and a resistance meter in human umbilical vein endothelial cells. Specific agonists or antagonists were applied to control the activation of S1P receptors and the release of calcium from different cellular compartments. The results indicated that at physiological concentrations, S1P preserved endothelial barrier function by binding with S1PR1. The activation of S1PR1 triggered the release of intracellular Ca(2+) from the endoplasmic reticulum through the PI-phospholipase C and inositol trisphosphate pathways. Consequently, the Rho GTPase Rac1 was activated, strengthening the assembly of tight junction proteins and F-actin. However, excessive S1P induced endothelial barrier dysfunction by activating S1PR2 followed by the RhoA/RhoA kinase pathway, causing the disorganization of F-actin and the disassembly of the tight junction protein ZO-1. An influx of extracellular Ca(2+) was involved in this process. These data suggest that physiological and excessive amounts of S1P induce different responses in human umbilical vein endothelial cells; the activation of the 1PR1-PLC-IP3 R-Ca(2+) -Rac1 pathway governs the low-dose S1P-enhanced endothelial barrier integrity, and the activation of S1PR2-calcium influx-RhoA/ROCK dominates the high-dose S1P-induced endothelial monolayer hyperpermeability response.
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Affiliation(s)
- Qiang Li
- Department of Pathophysiology, Key Laboratory for Shock and Microcirculation Research of Guangdong Province, Southern Medical University, Guangzhou, 510515, PR China
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Ebeling S, Naumann K, Pollok S, Wardecki T, Vidal-y-Sy S, Nascimento JM, Boerries M, Schmidt G, Brandner JM, Merfort I. From a traditional medicinal plant to a rational drug: understanding the clinically proven wound healing efficacy of birch bark extract. PLoS One 2014; 9:e86147. [PMID: 24465925 PMCID: PMC3899119 DOI: 10.1371/journal.pone.0086147] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Accepted: 12/05/2013] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND Birch bark has a long lasting history as a traditional medicinal remedy to accelerate wound healing. Recently, the efficacy of birch bark preparations has also been proven clinically. As active principle pentacyclic triterpenes are generally accepted. Here, we report a comprehensive study on the underlying molecular mechanisms of the wound healing properties of a well-defined birch bark preparation named as TE (triterpene extract) as well as the isolated single triterpenes in human primary keratinocytes and porcine ex-vivo wound healing models. METHODOLOGY/PRINCIPAL FINDINGS We show positive wound healing effects of TE and betulin in scratch assay experiments with primary human keratinocytes and in a porcine ex-vivo wound healing model (WHM). Mechanistical studies elucidate that TE and betulin transiently upregulate pro-inflammatory cytokines, chemokines and cyclooxygenase-2 on gene and protein level. For COX-2 and IL-6 this increase of mRNA is due to an mRNA stabilizing effect of TE and betulin, a process in which p38 MAPK and HuR are involved. TE promotes keratinocyte migration, putatively by increasing the formation of actin filopodia, lamellipodia and stress fibers. Detailed analyses show that the TE components betulin, lupeol and erythrodiol exert this effect even in nanomolar concentrations. Targeting the actin cytoskeleton is dependent on the activation of Rho GTPases. CONCLUSION/SIGNIFICANCE Our results provide insights to understand the molecular mechanism of the clinically proven wound healing effect of birch bark. TE and betulin address the inflammatory phase of wound healing by transient up-regulation of several pro-inflammatory mediators. Further, they enhance migration of keratinocytes, which is essential in the second phase of wound healing. Our results, together with the clinically proven efficacy, identify birch bark as the first medical plant with a high potential to improve wound healing, a field which urgently needs effective remedies.
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Affiliation(s)
- Sandra Ebeling
- Pharmaceutical Biology and Biotechnology, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Katrin Naumann
- Pharmaceutical Biology and Biotechnology, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Simone Pollok
- Department of Dermatology and Venerology, University Hospital Hamburg-Eppendorf, Hamburg, Germany
| | - Tina Wardecki
- Pharmaceutical Biology and Biotechnology, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Sabine Vidal-y-Sy
- Department of Dermatology and Venerology, University Hospital Hamburg-Eppendorf, Hamburg, Germany
| | - Juliana M. Nascimento
- Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University Freiburg, Freiburg, Germany
- German Cancer Consortium (DKTK), Heidelberg, Germany
| | - Melanie Boerries
- Institute of Molecular Medicine and Cell Research, Albert-Ludwigs-University Freiburg, Freiburg, Germany
- German Cancer Consortium (DKTK), Heidelberg, Germany
- German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Gudula Schmidt
- Institute for Experimental and Clinical Pharmacology and Toxicology, Albert-Ludwigs-University Freiburg, Freiburg, Germany
| | - Johanna M. Brandner
- Department of Dermatology and Venerology, University Hospital Hamburg-Eppendorf, Hamburg, Germany
| | - Irmgard Merfort
- Pharmaceutical Biology and Biotechnology, Albert-Ludwigs-University Freiburg, Freiburg, Germany
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Antunes M, Pereira T, Cordeiro JV, Almeida L, Jacinto A. Coordinated waves of actomyosin flow and apical cell constriction immediately after wounding. J Cell Biol 2013; 202:365-79. [PMID: 23878279 PMCID: PMC3718973 DOI: 10.1083/jcb.201211039] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Accepted: 06/14/2013] [Indexed: 12/31/2022] Open
Abstract
Epithelial wound healing relies on tissue movements and cell shape changes. Our work shows that, immediately after wounding, there was a dramatic cytoskeleton remodeling consisting of a pulse of actomyosin filaments that assembled in cells around the wound edge and flowed from cell to cell toward the margin of the wound. We show that this actomyosin flow was regulated by Diaphanous and ROCK and that it elicited a wave of apical cell constriction that culminated in the formation of the leading edge actomyosin cable, a structure that is essential for wound closure. Calcium signaling played an important role in this process, as its intracellular concentration increased dramatically immediately after wounding, and down-regulation of transient receptor potential channel M, a stress-activated calcium channel, also impaired the actomyosin flow. Lowering the activity of Gelsolin, a known calcium-activated actin filament-severing protein, also impaired the wound response, indicating that cleaving the existing actin filament network is an important part of the cytoskeleton remodeling process.
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Affiliation(s)
- Marco Antunes
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, 1649-028 Lisboa, Portugal
- Centro de Estudos de Doenças Crónicas (CEDOC), Faculdade de Ciências Médicas, Universidade Nova de Lisboa, 1169-056 Lisboa, Portugal
| | - Telmo Pereira
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, 1649-028 Lisboa, Portugal
- Centro de Estudos de Doenças Crónicas (CEDOC), Faculdade de Ciências Médicas, Universidade Nova de Lisboa, 1169-056 Lisboa, Portugal
| | - João V. Cordeiro
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | - Luis Almeida
- Laboratoire Jacques-Louis Lions, Université Pierre et Marie Curie and Centre National de la Recherche Scientifique, F75252 Paris, France
| | - Antonio Jacinto
- Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, 1649-028 Lisboa, Portugal
- Centro de Estudos de Doenças Crónicas (CEDOC), Faculdade de Ciências Médicas, Universidade Nova de Lisboa, 1169-056 Lisboa, Portugal
- Instituto Gulbenkian de Ciência, 2780-156 Oeiras, Portugal
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12
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Garland P, Broom LJ, Quraishe S, Dalton PD, Skipp P, Newman TA, Perry VH. Soluble axoplasm enriched from injured CNS axons reveals the early modulation of the actin cytoskeleton. PLoS One 2012; 7:e47552. [PMID: 23115653 PMCID: PMC3480358 DOI: 10.1371/journal.pone.0047552] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Accepted: 09/18/2012] [Indexed: 12/12/2022] Open
Abstract
Axon injury and degeneration is a common consequence of diverse neurological conditions including multiple sclerosis, traumatic brain injury and spinal cord injury. The molecular events underlying axon degeneration are poorly understood. We have developed a novel method to enrich for axoplasm from rodent optic nerve and characterised the early events in Wallerian degeneration using an unbiased proteomics screen. Our detergent-free method draws axoplasm into a dehydrated hydrogel of the polymer poly(2-hydroxyethyl methacrylate), which is then recovered using centrifugation. This technique is able to recover axonal proteins and significantly deplete glial contamination as confirmed by immunoblotting. We have used iTRAQ to compare axoplasm-enriched samples from naïve vs injured optic nerves, which has revealed a pronounced modulation of proteins associated with the actin cytoskeleton. To confirm the modulation of the actin cytoskeleton in injured axons we focused on the RhoA pathway. Western blotting revealed an augmentation of RhoA and phosphorylated cofilin in axoplasm-enriched samples from injured optic nerve. To investigate the localisation of these components of the RhoA pathway in injured axons we transected axons of primary hippocampal neurons in vitro. We observed an early modulation of filamentous actin with a concomitant redistribution of phosphorylated cofilin in injured axons. At later time-points, RhoA is found to accumulate in axonal swellings and also colocalises with filamentous actin. The actin cytoskeleton is a known sensor of cell viability across multiple eukaryotes, and our results suggest a similar role for the actin cytoskeleton following axon injury. In agreement with other reports, our data also highlights the role of the RhoA pathway in axon degeneration. These findings highlight a previously unexplored area of axon biology, which may open novel avenues to prevent axon degeneration. Our method for isolating CNS axoplasm also represents a new tool to study axon biology.
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Affiliation(s)
- Patrick Garland
- Centre for Biological Sciences, University of Southampton, Southampton General Hospital, Southampton, United Kingdom.
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Cheng H, Wang B, Tang C, Feng G, Zhang C, Li L, Lin T, Du F, Duan H, Shi M, Zhao G. Infrasonic noise induces axonal degeneration of cultured neurons via a Ca2+ influx pathway. Toxicol Lett 2012; 212:190-7. [DOI: 10.1016/j.toxlet.2012.05.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Revised: 05/09/2012] [Accepted: 05/14/2012] [Indexed: 11/17/2022]
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14
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Exosomes released by K562 chronic myeloid leukemia cells promote angiogenesis in a Src-dependent fashion. Angiogenesis 2011; 15:33-45. [PMID: 22203239 DOI: 10.1007/s10456-011-9241-1] [Citation(s) in RCA: 251] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Accepted: 11/04/2011] [Indexed: 12/11/2022]
Abstract
Exosomes, microvesicles of endocytic origin released by normal and tumor cells, play an important role in cell-to-cell communication. Angiogenesis has been shown to regulate progression of chronic myeloid leukemia (CML). The mechanism through which this happens has not been elucidated. We isolated and characterized exosomes from K562 CML cells and evaluated their effects on human umbilical endothelial cells (HUVECs). Fluorescent-labeled exosomes were internalized by HUVECs during tubular differentiation on Matrigel. Exosome localization was perinuclear early in differentiation, moving peripherally in cells undergoing elongation and connection. Exosomes move within and between nanotubular structures connecting the remodeling endothelial cells. They stimulated angiotube formation over a serum/growth factor-limited medium control, doubling total cumulative tube length (P = 0.003). Treatment of K562 cells with two clinically active tyrosine kinase inhibitors, imatinib and dasatinib, reduced their total exosome release (P < 0.009); equivalent concentrations of drug-treated exosomes induced a similar extent of tubular differentiation. However, dasatinib treatment of HUVECs markedly inhibited HUVEC response to drug control CML exosomes (P < 0.002). In an in vivo mouse Matrigel plug model angiogenesis was induced by K562 exosomes and abrogated by oral dasatinib treatment (P < 0.01). K562 exosomes induced dasatinib-sensitive Src phosphorylation and activation of downstream Src pathway proteins in HUVECs. Imatinib was minimally active against exosome stimulation of HUVEC cell differentiation and signaling. Thus, CML cell-derived exosomes induce angiogenic activity in HUVEC cells. The inhibitory effect of dasatinib on exosome production and vascular differentiation and signaling reveals a key role for Src in both the leukemia and its microenvironment.
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15
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Recognition of CD146 as an ERM-binding protein offers novel mechanisms for melanoma cell migration. Oncogene 2011; 31:306-21. [DOI: 10.1038/onc.2011.244] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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16
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Röck K, Grandoch M, Majora M, Krutmann J, Fischer JW. Collagen fragments inhibit hyaluronan synthesis in skin fibroblasts in response to ultraviolet B (UVB): new insights into mechanisms of matrix remodeling. J Biol Chem 2011; 286:18268-76. [PMID: 21454612 DOI: 10.1074/jbc.m110.201665] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
UVB irradiation causes characteristic features of skin aging including remodeling of the dermal extracellular matrix. A key feature during this process is the up-regulation of matrix metalloproteinases and cleavage of collagen. Hyaluronic acid (HA), a major component of the dermal matrix, decreases after chronic UVB exposure. However, the factors that govern the decline of HA synthesis during the course of actinic aging are largely unknown. The aim of the present study was to explore whether collagen degradation causes inhibition of HA synthesis in human skin fibroblasts. After treatment of fibroblasts with collagen fragments (CF) in vitro, resolution of the actin cytoskeleton and inhibition of HA secretion occurred because of specific down-regulation of hyaluronan synthase 2 (HAS2) expression. The α(v)β(3)-agonist, RGDS, latrunculin A, and an inhibitor of Rho-activated kinase inhibited HAS2 expression. Conversely, blocking antibodies to α(v)β(3) abolished the down-regulation of HAS2 and the cytoskeletal effects. Furthermore, inhibition of cofilin phosphorylation in response to CF was prevented by α(v)β(3)-blocking antibodies. The key role of ERK signaling was shown by reduced nuclear accumulation of phosphoERK and of ELK-1 phosphorylation in response to CF. In addition, the ERK inhibitor PD98059 reduced HAS2 expression. Also, UVB irradiation of fibroblasts caused down-regulation of HAS2, which was sensitive to matrix metalloproteinase inhibitors and to α(v)β(3)-blocking antibodies. In conclusion, these data suggest that CF activate α(v)β(3)-integrins and in turn inhibit Rho kinase (ROCK) signaling and nuclear translocation of phosphoERK, resulting in reduced HAS2 expression. Therefore, a novel mechanism is presented how proteolytic collagen cleavage may inhibit HA synthesis in dermal fibroblasts during extrinsic skin aging.
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Affiliation(s)
- Katharina Röck
- Institut für Pharmakologie und Klinische Pharmakologie, Universitätsklinikum Düsseldorf, 40225 Düsseldorf, Germany
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17
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Matsumoto N, Kitani R, Maricle A, Mueller M, Kalinec F. Pivotal role of actin depolymerization in the regulation of cochlear outer hair cell motility. Biophys J 2010; 99:2067-76. [PMID: 20923640 PMCID: PMC3042570 DOI: 10.1016/j.bpj.2010.08.015] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2010] [Revised: 08/09/2010] [Accepted: 08/13/2010] [Indexed: 11/28/2022] Open
Abstract
Cochlear outer hair cells undergo reversible changes in shape when externally stimulated. This response, known as OHC motility, is a central component of the cochlear amplifier, the mechanism responsible for the high sensitivity of mammalian hearing. We report that actin depolymerization, as regulated by activation/inhibition of LIMK/cofilin-mediated pathways, has a pivotal role in OHC motility. LIMK-mediated cofilin phosphorylation, which inhibits the actin depolymerizing activity of this protein, increases both electromotile amplitude and total length of guinea pig OHCs. In contrast, a decrease in cofilin phosphorylation reduces both OHC electromotile amplitude and OHC length. Experiments with acetylcholine and lysophosphatidic acid indicate that the effects of these agents on OHC motility are associated with regulation of cofilin phosphorylation via different signaling cascades. On the other hand, nonlinear capacitance measurements confirmed that all observed changes in OHC motile response were independent of the performance of the motor protein prestin. Altogether, these results strongly support the hypothesis that the cytoskeleton has a major role in the regulation of OHC motility, and identify actin depolymerization as a key process for modulating cochlear amplification.
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MESH Headings
- Acetylcholine/pharmacology
- Actin Depolymerizing Factors/metabolism
- Actins/metabolism
- Animals
- Bridged Bicyclo Compounds, Heterocyclic/pharmacology
- Cell Movement/drug effects
- Cell Separation
- Guinea Pigs
- Hair Cells, Auditory, Outer/cytology
- Hair Cells, Auditory, Outer/drug effects
- Hair Cells, Auditory, Outer/enzymology
- Hair Cells, Auditory, Outer/metabolism
- Lim Kinases/metabolism
- Lysophospholipids/pharmacology
- Models, Biological
- Phosphorylation/drug effects
- Protein Transport/drug effects
- Receptors, Lysophosphatidic Acid/metabolism
- Signal Transduction/drug effects
- Thiazolidines/pharmacology
- rho-Associated Kinases/metabolism
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Affiliation(s)
- Nozomu Matsumoto
- Department of Otorhinolaryngology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
- Division of Cell Biology and Genetics, House Ear Institute, Los Angeles, California
| | - Rei Kitani
- Division of Cell Biology and Genetics, House Ear Institute, Los Angeles, California
| | - Anastasiya Maricle
- Division of Cell Biology and Genetics, House Ear Institute, Los Angeles, California
| | - Melissa Mueller
- Division of Cell Biology and Genetics, House Ear Institute, Los Angeles, California
| | - Federico Kalinec
- Division of Cell Biology and Genetics, House Ear Institute, Los Angeles, California
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18
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Inamori M, Mizumoto H, Kajiwara T. An approach for formation of vascularized liver tissue by endothelial cell-covered hepatocyte spheroid integration. Tissue Eng Part A 2009; 15:2029-37. [PMID: 19320555 DOI: 10.1089/ten.tea.2008.0403] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Tissue vascularization in vitro is necessary for cell transplantation and is a major challenge in tissue engineering. To construct large and regularly vascularized tissue, we focused on the integration of endothelial cell-covered spheroids. Primary rat hepatocytes were cultured on a rotary shaker, and 100-150 mum spheroids were obtained by filtration. The hepatocyte spheroids were coated with collagen by conjugation with a type 1 collagen solution. Collagen-coated hepatocyte spheroids were cocultured with human umbilical vein endothelial cells (HUVECs), and monolayered HUVEC-covered hepatocyte spheroids were constructed. Without a collagen coat, many HUVECs invaded hepatocyte spheroids but did not cover the spheroid surface. To construct regularly vascularized tissue, we packed HUVEC-covered hepatocyte spheroids in hollow fibers used for plasma separation. Packed spheroids attached to each other forming a large cellular tissue with regular distribution of HUVECs. At day 9 after packing, HUVECs invaded the hepatocyte spheroids and a dense vascular network was constructed. Collagen coating of spheroids is useful for the formation of endothelial cell-covered spheroids and subsequent regular vascularized tissue construction.
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Affiliation(s)
- Masakazu Inamori
- Department of Chemical Engineering, Faculty of Engineering, Kyushu University , Fukuoka, Japan
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19
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Sachdev S, Bu Y, Gelman IH. Paxillin-Y118 phosphorylation contributes to the control of Src-induced anchorage-independent growth by FAK and adhesion. BMC Cancer 2009; 9:12. [PMID: 19138410 PMCID: PMC2651180 DOI: 10.1186/1471-2407-9-12] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2008] [Accepted: 01/12/2009] [Indexed: 01/10/2023] Open
Abstract
Background Focal adhesion kinase (FAK) and Src are protein tyrosine kinases that physically and functionally interact to facilitate cancer progression by regulating oncogenic processes such as cell motility, survival, proliferation, invasiveness, and angiogenesis. Method To understand how FAK affects oncogenesis through the phosphorylation of cellular substrates of Src, we analyzed the phosphorylation profile of a panel of Src substrates in parental and v-Src-expressing FAK+/+ and FAK-/- mouse embryo fibroblasts, under conditions of anchorage-dependent (adherent) and -independent (suspension) growth. Results Total Src-induced cellular tyrosine phosphorylation as well as the number of phosphotyrosyl substrates was higher in suspension versus adherent cultures. Although the total level of Src-induced cellular phosphorylation was similar in FAK+/+ and FAK-/- backgrounds, the phosphorylation of some substrates was influenced by FAK depending on adherence state. Specifically, in the absence of FAK, Src induced higher phosphorylation of p190RhoGAP, paxillin (poY118) and Crk irrespective of adhesion state, PKC-δ (poY311), connexin-43 (poY265) and Sam68 only under adherent conditions, and p56Dok-2 (poY351) and p120catenin (poY228) only under suspension conditions. In contrast, FAK enhanced the Src-induced phosphorylation of vinculin (poY100 and poY1065) and p130CAS (poY410) irrespective of adherence state, p56Dok-2 (poY351) and p120catenin (poY228) only under adherent conditions, and connexin-43 (poY265), cortactin (poY421) and paxillin (poY31) only under suspension conditions. The Src-induced phosphorylation of Eps8, PLC-γ1 and Shc (poY239/poY240) were not affected by either FAK or adherence status. The enhanced anchorage-independent growth of FAK-/-[v-Src] cells was selectively decreased by expression of paxillinY118F, but not by WT-paxillin, p120cateninY228F or ShcY239/240F, identifying for the first time a role for paxillinpoY118 in Src-induced anchorage-independent growth. Knockdown of FAK by siRNA in the human colon cancer lines HT-25 and RKO, resulted in increased paxillinpoY118 levels under suspension conditions as well as increased anchorage-independent growth, supporting the notion that FAK attenuates anchorage-independent growth by suppressing adhesion-dependent phosphorylation of paxillinY118. Conclusion These data suggest that phosphorylation of Src substrates is a dynamic process, influenced temporally and spatially by factors such as FAK and adhesion.
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Affiliation(s)
- Sanjay Sachdev
- Department of Cancer Genetics, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263, USA.
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20
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Dubash AD, Menold MM, Samson T, Boulter E, García-Mata R, Doughman R, Burridge K. Chapter 1 Focal Adhesions: New Angles on an Old Structure. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2009; 277:1-65. [DOI: 10.1016/s1937-6448(09)77001-7] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
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21
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Terryn C, Bonnomet A, Cutrona J, Coraux C, Tournier JM, Nawrocki-Raby B, Polette M, Birembaut P, Zahm JM. Video-microscopic imaging of cell spatio-temporal dispersion and migration. Crit Rev Oncol Hematol 2008; 69:144-52. [PMID: 18657992 DOI: 10.1016/j.critrevonc.2008.06.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2008] [Revised: 04/21/2008] [Accepted: 06/18/2008] [Indexed: 11/29/2022] Open
Abstract
Live-cell imaging has become a powerful analytical tool in most cell biology laboratories. The scope of this paper is to give an overview of the environmental considerations for maintaining living cells on the microscope stage and the technical advances permitting multi-parameter imaging. The paper will then focus on two-dimensional and three-dimensional analysis of cell dispersion and migration and finally give a brief insight on computational modeling of the cell behavior.
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22
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Tilghman RW, Parsons JT. Focal adhesion kinase as a regulator of cell tension in the progression of cancer. Semin Cancer Biol 2007; 18:45-52. [PMID: 17928235 DOI: 10.1016/j.semcancer.2007.08.002] [Citation(s) in RCA: 120] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2007] [Accepted: 08/28/2007] [Indexed: 01/13/2023]
Abstract
Growing evidence indicates that critical steps in cancer progression such as cell adhesion, migration, and cell cycle progression are regulated by the composition and organization of the microenvironment. The adhesion of cancer cells to components of the microenvironment and the forces transmitted to the cells via the actinomyosin network and the signaling complexes organized within focal adhesions allow cancer cells to sense the local topography of the extracellular matrix and respond efficiently to proximal growth and migration promoting cues. Focal adhesion kinase (FAK) is a nonreceptor tyrosine kinase that is over expressed in a variety of cancers and plays an important role in cell adhesion, migration, and anchorage-dependent growth. In this review, we summarize evidence which implicate FAK in the ability of cells to sense and respond to local forces from the microenvironment through the regulation of adhesion dynamics and actinomyosin contractility, and we discuss the potential roles of FAK as a mechanosensor in the progression of cancer.
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Affiliation(s)
- Robert W Tilghman
- Department of Microbiology, University of Virginia Health System, Charlottesville, VA 22908, USA
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Holinstat M, Knezevic N, Broman M, Samarel AM, Malik AB, Mehta D. Suppression of RhoA activity by focal adhesion kinase-induced activation of p190RhoGAP: role in regulation of endothelial permeability. J Biol Chem 2005; 281:2296-305. [PMID: 16308318 DOI: 10.1074/jbc.m511248200] [Citation(s) in RCA: 126] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The interaction of endothelial cells with extracellular matrix proteins at focal adhesions sites contributes to the integrity of vascular endothelial barrier. Although focal adhesion kinase (FAK) activation is required for the recovery of the barrier function after increased endothelial junctional permeability, the basis for the recovery remains unclear. We tested the hypothesis that FAK activates p190RhoGAP and, thus, negatively regulates RhoA activity and promotes endothelial barrier restoration in response to the permeability-increasing mediator thrombin. We observed that thrombin caused a transient activation of RhoA but a more prolonged FAK activation temporally coupled to the recovery of barrier function. Thrombin also induced tyrosine phosphorylation of p190RhoGAP, which coincided with decrease in RhoA activity. We further showed that FAK was associated with p190RhoGAP, and importantly, recombinant FAK phosphorylated p190RhoGAP in vitro. Inhibition of FAK by adenoviral expression of FRNK (a dominant negative FAK construct) in monolayers prevented p190RhoGAP phosphorylation, increased RhoA activity, induced actin stress fiber formation, and produced an irreversible increase in endothelial permeability in response to thrombin. We also observed that p190RhoGAP was unable to attenuate RhoA activation in the absence of FAK activation induced by FRNK. The inhibition of RhoA by the C3 toxin (Clostridium botulinum toxin) restored endothelial barrier function in the FRNK-expressing cells. These findings in endothelial cells were recapitulated in the lung microcirculation in which FRNK expression in microvessel endothelia increased vascular permeability. Our studies demonstrate that FAK-induced down-modulation of RhoA activity via p190RhoGAP is a crucial step in signaling endothelial barrier restoration after increased endothelial permeability.
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Affiliation(s)
- Michael Holinstat
- Department of Pharmacology and Center for Lung and Vascular Biology, College of Medicine, The University of Illinois, 835 S. Wolcott Avenue, Chicago, IL 60612, USA
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Palm D, Lang K, Brandt B, Zaenker KS, Entschladen F. In vitro and in vivo imaging of cell migration: Two interdepending methods to unravel metastasis formation. Semin Cancer Biol 2005; 15:396-404. [PMID: 16054391 DOI: 10.1016/j.semcancer.2005.06.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Metastasis development requires the migratory activity of tumor cells. It is therefore important to understand the molecular mechanisms of this migration in order to prevent metastasis development, which is the pernicious step in most solid tumor diseases. A lot of methods have been invented to investigate tumor cell migration, but not all are equally suited and no method alone is able to deliver a complete picture of tumor cell migration. We herein suggest a combination of three-dimensional in vitro and in vivo methods for the investigation of tumor cell migration and summarize the knowledge, which has been reached so far.
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Affiliation(s)
- Daniel Palm
- Institute of Immunology, Witten/Herdecke University, Stockumer Str. 10, 58448 Witten, Germany
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25
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Hoffmann S, He S, Jin ML, Masiero L, Wiedemann P, Ryan SJ, Kohn EC. Carboxyamido-triazole modulates retinal pigment epithelial and choroidal endothelial cell attachment, migration, proliferation, and MMP-2 secretion of choroidal endothelial cells. Curr Eye Res 2005; 30:103-13. [PMID: 15814468 DOI: 10.1080/02713680490894595] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
PURPOSE To determine the effect of the calcium signaling modulating drug carboxyamido-triazole (CAI) on substeps of exudative age-related macular degeneration (AMD) in vitro. MATERIALS AND METHODS Zymography and ELISA determined the effect of CAI on MMP-2 production of choroidal endothelial cells (CECs) stimulated by bFGF and VEGF. The effects of CAI on attachment of retinal pigment endothelial (RPE) cells/CECs onto fibronectin, laminin, collagen IV, and migration toward fibronectin were investigated. Proliferation induced by serum and bFGF (10 microg/ml) with and without CAI (0.1-10 microM) was measured by cell counting and 3H-uptake. Viability and apoptosis of the exposed cells was assessed by an MTT and an apoptosis assay. RESULTS CAI inhibited serum- and bFGF-induced proliferation, cell attachment onto fibronectin and collagen IV, but only CEC attachment onto laminin. Inhibition of MMP-2 production was observed (10 microM CAI). CAI reduced the cellular viability by apoptosis induction. CONCLUSIONS CAI inhibits substeps of exudative macular degeneration and may be of value for the treatment of the disease.
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Affiliation(s)
- Stephan Hoffmann
- Department of Ophthalmology, University of Leipzig, Leipzig, Germany.
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Entschladen F, Drell TL, Lang K, Masur K, Palm D, Bastian P, Niggemann B, Zaenker KS. Analysis methods of human cell migration. Exp Cell Res 2005; 307:418-26. [PMID: 15950622 DOI: 10.1016/j.yexcr.2005.03.029] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2005] [Revised: 03/22/2005] [Accepted: 03/24/2005] [Indexed: 11/26/2022]
Abstract
The autonomous migration of specialized cells is an essential characteristic in both physiological and pathological functions in the adult human organism. Leukocytes, fibroblasts, and stem cells, but also tumor cells, are thus the subject of intense investigation in a broad range of research fields. A wide spectrum of methods have therefore been established to analyze chemokinetic and chemotactic cell migration, ranging from easy-to-handle two-dimensional surface migration assays to highly specialized three-dimensional and intravital analysis methods. It is now manifest that the results obtained with these various migration assays substantially differ. This review therefore gives an overview of the migration assays which are currently in use, describes the methods, and critically enlightens the particular advantages and disadvantages of each method.
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Affiliation(s)
- Frank Entschladen
- Institute of Immunology, Witten/Herdecke University, Stockumer Street 10, 58448 Witten, Germany.
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Continolo S, Baruzzi A, Majeed M, Caveggion E, Fumagalli L, Lowell CA, Berton G. The proto-oncogene Fgr regulates cell migration and this requires its plasma membrane localization. Exp Cell Res 2005; 302:253-69. [PMID: 15561106 DOI: 10.1016/j.yexcr.2004.09.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2004] [Revised: 08/25/2004] [Indexed: 12/31/2022]
Abstract
Fgr participates in integrin signaling in myeloid leukocytes. To examine the role of its specific domains in regulating cell migration, we expressed various Fgr molecules in COS-7 cells. Full-length, membrane-bound Fgr, but not an N-terminal truncation mutant that distributed to an intracellular compartment, increased cell migration on fibronectin and enhanced phosphorylation of the p85 subunit of phosphatidylinositol 3-kinase (PI3K), cortactin and focal adhesion kinase (FAK) at Y397 and Y576. Fgr increased Rac GTP loading, and phosphorylation of the Rac GEF Vav2, and bound to a protein complex formed by the Rho inhibitor p190RhoGAP and FAK, increasing p190RhoGAP phosphorylation, in a manner absolutely dependent on membrane localization. A kinase-defective truncation mutant of Fgr increased cell migration, albeit to a much lower extent than full-length Fgr, and was found to associate with the plasma membrane, to activate Rac and to form complexes with p190RhoGAP/FAK. Formation of complexes between p190RhoGAP, Fgr, and the FAK-related protein Pyk2 were also detected in murine macrophages. These findings suggest that the proto-oncogene Fgr regulates cell migration impinging on a signaling pathway implicating FAK/Pyk2 and leading to activation of Rac and the Rho inhibitor p190RhoGAP.
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Affiliation(s)
- Silvia Continolo
- Department of Pathology, Section of General Pathology, University of Verona, Verona, Italy
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Abstract
The inositol 1,4,5 trisphosphate (IP3) receptor (IP3R) is a Ca2+ release channel that responds to the second messenger IP3. Exquisite modulation of intracellular Ca2+ release via IP3Rs is achieved by the ability of IP3R to integrate signals from numerous small molecules and proteins including nucleotides, kinases, and phosphatases, as well as nonenzyme proteins. Because the ion conduction pore composes only approximately 5% of the IP3R, the great bulk of this large protein contains recognition sites for these substances. Through these regulatory mechanisms, IP3R modulates diverse cellular functions, which include, but are not limited to, contraction/excitation, secretion, gene expression, and cellular growth. We review the unique properties of the IP3R that facilitate cell-type and stimulus-dependent control of function, with special emphasis on protein-binding partners.
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Affiliation(s)
- Randen L Patterson
- Department of Neuroscience, Johns Hopkins University, Johns Hopkins Medical School, Baltimore, Maryland 21205, USA.
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29
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Zheng PP, Sieuwerts AM, Luider TM, van der Weiden M, Sillevis-Smitt PAE, Kros JM. Differential expression of splicing variants of the human caldesmon gene (CALD1) in glioma neovascularization versus normal brain microvasculature. THE AMERICAN JOURNAL OF PATHOLOGY 2004; 164:2217-28. [PMID: 15161654 PMCID: PMC1615785 DOI: 10.1016/s0002-9440(10)63778-9] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 02/23/2004] [Indexed: 12/15/2022]
Abstract
Caldesmon is a cytoskeleton-associated protein which has not yet been related to neoplastic angiogenesis. In this study we investigated the expression of the caldesmon gene (CALD1) splicing variants and the protein expression level in glioma microvessels versus normal brain microvasculature. To exclude sources of splice variant expression from non-vascular components all possible cellular components present in control and glioma samples were pre-screened by laser-capture microdissection followed by RT-PCR before the cohort study. We discovered differential expression of the splicing variants of CALD1 in the tumor microvessels in contrast to normal brain microvasculature. Missplicing of exons 1, 1 + 4, and 1' + 4 of the gene is exclusively found in glioma microvessels. To exclude the possibility that this missplicing results from splice-site mutations, mutation scanning was performed by a coupled in vitro transcription/translation assay (IVTT). No premature stop mutations were traced by the IVTT. The transcriptional changes consequently resulted in up-regulation at the protein expression level. The up-regulated expression of caldesmon was coincident with the down-regulated expression of tight junction proteins (occludin and ZO-1). The results support the notion that missplicing of the CALD1 gene in glioma microvasculature is an independent epigenetic event regulated at the transcriptional level. The event coexists with tight junction (TJ) breakdown of the endothelial cells in glioma microvasculature. The data reveal a novel mechanism contributing to dysfunctionality of glioma neovascularization.
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Affiliation(s)
- Ping-Pin Zheng
- Department of Pathology, Internal Oncology, Neuro-Oncology and Neurology, Erasmus Medical Center, Rotterdam, The Netherlands
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Kole TP, Tseng Y, Huang L, Katz JL, Wirtz D. Rho kinase regulates the intracellular micromechanical response of adherent cells to rho activation. Mol Biol Cell 2004; 15:3475-84. [PMID: 15146061 PMCID: PMC452598 DOI: 10.1091/mbc.e04-03-0218] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Local sol-gel transitions of the cytoskeleton modulate cell shape changes, which are required for essential cellular functions, including motility and adhesion. In vitro studies using purified cytoskeletal proteins have suggested molecular mechanisms of regulation of cytoskeleton mechanics; however, the mechanical behavior of living cells and the signaling pathways by which it is regulated remains largely unknown. To address this issue, we used a nanoscale sensing method, intracellular microrheology, to examine the mechanical response of the cell to activation of the small GTPase Rho. We observe that the cytoplasmic stiffness and viscosity of serum-starved Swiss 3T3 cells transiently and locally enhances upon treatment with lysophosphatidic acid, and this mechanical behavior follows a trend similar to Rho activity. Furthermore, the time-dependent activation of Rho decreases the degree of microheterogeneity of the cytoplasm. Our results reveal fundamental differences between intracellular elasticity and cellular tension and suggest a critical role for Rho kinase in the regulation of intracellular mechanics.
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Affiliation(s)
- Thomas P Kole
- Department of Chemical and Biomolecular Engineering, The Johns Hopkins University, Baltimore, Maryland 21218, USA
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31
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Gottfried C, Cechin SR, Gonzalez MA, Vaccaro TS, Rodnight R. The influence of the extracellular matrix on the morphology and intracellular pH of cultured astrocytes exposed to media lacking bicarbonate. Neuroscience 2004; 121:553-62. [PMID: 14568017 DOI: 10.1016/s0306-4522(03)00557-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In previous work we showed that the polygonal shape of hippocampal astrocytes cultured on poly-L-lysine changes to a stellate morphology with loss of actinomyosin stress fibers on exchanging the culture medium for saline buffered with HEPES [Brain Res 946 (2002)12]. By contrast, in bicarbonate-buffered saline containing Ca(2+) astrocytes remained polygonal and continued to express stress fibers. Evidence suggests that stellation induced by saline buffered with HEPES is related to intracellular acidification due to the absence of bicarbonate. Here we studied the influence of the matrix used in preparing astrocyte cultures. Stellation in HEPES-saline occurred on a matrix of fibronectin, but not on matrices of collagen I or IV provided Ca(2+) was present. Laminin partially prevented stellation in HEPES-saline. Further, the intracellular acidification induced by HEPES-saline observed in astrocytes cultured on polylysine was abolished in cells cultured on collagens and was attentuated on a matrix of laminin. Two observations suggested the involvement of integrins and focal adhesions. (1) Treatment of cultures on collagens with a blocking antibody to the beta1 integrin subunit abolished protection against HEPES-induced stellation. (2) Compared with polylysine, astrocytes cultured on collagens expressed increased contents of phosphotyrosine proteins, focal adhesion proteins vinculin and paxillin, the beta1 integrin subunit and increased numbers of focal adhesions labelled with anti-vinculin. The observation that astrocytes cultured on collagen I or IV, in contrast to polylysine, express stress fibers and a constant intracellular pH in the absence of buffering by bicarbonate may be related to the fact that in the intact brain astrocytic processes (or end-feet) encounter and bind to collagen IV and laminin in the basement membrane of the endothelial cells which surround the cerebral capillaries. It is also possible that astrocytes retain this capacity from early development when fibrous matrix proteins are present.
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Affiliation(s)
- C Gottfried
- Centro de Ciências da Saúde, Unisinos, Sao Leopoldo, Brazil
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32
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Hussain MM, Kotz H, Minasian L, Premkumar A, Sarosy G, Reed E, Zhai S, Steinberg SM, Raggio M, Oliver VK, Figg WD, Kohn EC. Phase II trial of carboxyamidotriazole in patients with relapsed epithelial ovarian cancer. J Clin Oncol 2004; 21:4356-63. [PMID: 14645425 DOI: 10.1200/jco.2003.04.136] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
PURPOSE Carboxyamidotriazole (CAI) is a cytostatic inhibitor of nonvoltage-operated calcium channels and calcium channel-mediated signaling pathways. It inhibits angiogenesis, tumor growth, invasion, and metastasis. We hypothesized that CAI would promote disease stabilization lasting >/= 6 months in patients with relapsed ovarian cancer. PATIENTS AND METHODS Patients with epithelial ovarian cancer, good end-organ function, measurable disease, and three or fewer prior regimens were eligible. Oral CAI was given daily using a pharmacokinetic-dosing approach to maintain plasma concentrations between 2 and 4 microg/mL. Radiographic imaging to assess response was performed every 8 weeks. Positive outcome included stabilization or improvement of disease lasting >/= 6 months. Plasma vascular endothelial growth factor (VEGF), interleukin (IL)-8, and matrix metalloproteinase (MMP)-2 were measured. RESULTS Thirty-six patients were assessable for primary end point analysis, and 38 were assessable for toxicity. Forty-four percent of patients had three prior regimens, more than 50% had four or more disease sites, and 48% had liver metastases. Thirty-three patients reached the targeted concentration range during the first cycle. Eleven patients (31%) attained the >/= 6-month outcome end point, with one partial response (8 months) and three minor responses (8, 12+, and 13 months). Median time to progression was 3.6 months (range, 1.6 to 13.3 months). CAI was well tolerated, with mostly grade 1 to 2 toxicity. Grade 3 events included fatigue (5%), vomiting (2%), neutropenic fever (2%), and neutropenia (2%). There were no grade 4 adverse events. No associations between VEGF, IL-8, and MMP-2 with CAI concentration or clinical outcome were observed. CONCLUSION CAI is a potential agent for additional study in the stabilization of relapsed ovarian cancer. Given a limited toxicity profile, it may have utility as a maintenance therapeutic agent for this disease.
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MESH Headings
- Administration, Oral
- Adult
- Aged
- Aged, 80 and over
- Antineoplastic Agents/adverse effects
- Antineoplastic Agents/pharmacokinetics
- Antineoplastic Agents/therapeutic use
- Biomarkers/analysis
- Calcium Channel Blockers/adverse effects
- Calcium Channel Blockers/pharmacokinetics
- Calcium Channel Blockers/therapeutic use
- Carcinoma, Endometrioid/drug therapy
- Carcinoma, Endometrioid/metabolism
- Carcinoma, Papillary/drug therapy
- Carcinoma, Papillary/metabolism
- Cystadenocarcinoma, Serous/drug therapy
- Cystadenocarcinoma, Serous/metabolism
- Female
- Humans
- Middle Aged
- Neoplasm Recurrence, Local/drug therapy
- Neoplasm Recurrence, Local/metabolism
- Neoplasms, Glandular and Epithelial/drug therapy
- Neoplasms, Glandular and Epithelial/metabolism
- Ovarian Neoplasms/drug therapy
- Ovarian Neoplasms/metabolism
- Salvage Therapy
- Survival Rate
- Treatment Outcome
- Triazoles/adverse effects
- Triazoles/pharmacokinetics
- Triazoles/therapeutic use
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Affiliation(s)
- Mahrukh M Hussain
- Medical Oncology Clinical Research Unit, Medical Ovarian Cancer Clinic and Biostatistics and Data Management Section, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892-1500, USA
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Oliver VK, Patton AM, Desai S, Lorang D, Libutti SK, Kohn EC. Regulation of the pro-angiogenic microenvironment by carboxyamido-triazole. J Cell Physiol 2003; 197:139-48. [PMID: 12942550 DOI: 10.1002/jcp.10350] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Anti-angiogenic agents regulate tumor growth by inhibiting endothelial cell proliferation and invasion. Carboxyamido-triazole (CAI), an inhibitor of non-voltage-operated calcium entry and calcium influx-mediated pathways, has angiogenesis and invasion inhibitory activity. We hypothesized that CAI may express its anti-angiogenic effects through negative regulation of pro-angiogenic cytokine production and/or function. In vivo, orally administered CAI prevented A2058 human melanoma xenograft growth and concomitantly resulted in a marked reduction in circulating vascular endothelial growth factor (VEGF) and interleukin-8 (IL-8). In vitro, A2058 cell secretion of VEGF was inhibited by CAI treatment under limiting micronutrient conditions that approximate the tumor microenvironment, media restriction, and acidification to pH 6.8 (P=0.0003 and P=0.0006, respectively). VEGF and HIF-1alpha message and protein were also reduced by CAI treatment. Oral CAI treatment reduced vascular ingrowth in vivo into VEGF-containing Matrigel plugs. Commensurate with those findings, human umbilical vein endothelial cell (HUVEC) migration towards VEGF was reduced below background by exposure to CAI in the migration chamber (P<0.0001). An 88% reduction in circulating IL-8 concentration was measured in CAI-treated animals. However, IL-8 protein secretion and gene expression were increased by CAI treatment in culture (P< or =0.01), where CAI caused a dose-dependent acidification of the culture milieu (P< or =0.005). This paradox suggests that IL-8 production in vitro may be more sensitive to ambient pH than cytosolic calcium. These observations suggest that CAI inhibition of tumor cell VEGF production and endothelial cell response to VEGF results in disruption of signaling between the tumor and its microenvironment, causing a net anti-angiogenic effect.
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Affiliation(s)
- Vyta Kulpa Oliver
- Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland 20892-1500, USA
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Büyükafşar K, Levent A. Involvement of Rho/Rho-kinase signalling in the contractile activity and acetylcholine release in the mouse gastric fundus. Biochem Biophys Res Commun 2003; 303:777-81. [PMID: 12670478 DOI: 10.1016/s0006-291x(03)00422-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
In this study effects of Rho kinase inhibitors have been examined on the mouse gastric fundal smooth muscle reactivity and neurotransmitter (acetylcholine) release. Two Rho-kinase inhibitors, Y-27632 and fasudil (HA-1077), conspicuously suppressed the contractile responses to carbachol (CCh) and KCl as well as electrical field stimulation (EFS, 40 V, 0.5 ms, and 20 s). pEC(50) value for CCh and EC(50) value for KCl were 6.68+/-0.15 M and 10.4+/-2.8 mM, respectively. EFS induced reproducible contraction (38.3+/-4.75 mN/g tissue) which was almost abolished and potentiated in the presence of atropine (10(-6)M) and eserine (10(-6)M), respectively. The Rho-kinase inhibitors relaxed the fundic strips preconstricted by submaximal concentration of CCh or KCl in a concentration dependent manner. With CCh-elicited contraction, the pEC(50) values of Y-27632 and fasudil were 5.45+/-0.14 and 5.11+/-0.14 M, respectively (p>0.05). However, the pEC(50) values for Y-27632 and fasudil on KCl-induced tone were 6.09+/-0.1 and 5.35+/-0.06 M (p<0.001), respectively. Moreover, [3H]acetylcholine ([3H]ACh) release upon EFS from the gastric fundus was measured and it was found that Y-27632 (10(-4)M) significantly impaired the release. At 3 Hz the radioactivity ratio obtained after and before EFS (S(2)/S(1) ratio) was 0.88+/-0.03 in control but 0.63+/-0.08 in the presence of 10(-4)M Y-27632 (p<0.05). These results suggest that Rho kinase inhibitors can not only relax the gastric fundus but also modulate CCh, cholinergic nerve stimulation, and KCl-induced contraction. Furthermore, Rho/Rho kinase signalling may play a role in the neurotransmitter (ACh) release in the mouse gastric fundus.
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Affiliation(s)
- Kansu Büyükafşar
- Department of Pharmacology, Medical Faculty, Mersin University Campus, Yenişehir, Mersin 33169,
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35
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Singleton PA, Bourguignon LYW. CD44v10 interaction with Rho-kinase (ROK) activates inositol 1,4,5-triphosphate (IP3) receptor-mediated Ca2+ signaling during hyaluronan (HA)-induced endothelial cell migration. CELL MOTILITY AND THE CYTOSKELETON 2002; 53:293-316. [PMID: 12378540 DOI: 10.1002/cm.10078] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Aortic endothelial cells (GM7372A) express a major cell adhesion molecule, CD44v10, which binds the extracellular matrix component, hyaluronan (HA), at its external domain and interacts with various signaling molecules at its cytoplasmic domain. In this study, we have determined that CD44v10 and Rho-Kinase (ROK) are physically associated as a complex in vivo. Using a recombinant fragment of ROK (in particular, the pleckstrin homology [PH] domain) and in vitro binding assays, we have detected a specific binding interaction between the PH domain of ROK and the cytoplasmic domain of CD44. Scatchard plot analysis indicates that there is a single high-affinity CD44 binding site in the PH domain of ROK with an apparent dissociation constant (Kd) of 1.76 nM, which is comparable to CD44 binding (Kd approximately 1.56 nM) to intact ROK. These findings suggest that the PH domain is the primary ROK binding region for CD44. Furthermore, HA binding to GM7372A cells promotes RhoA-mediated ROK activity, which, in turn, increases phosphorylation of three different inositol 1, 4, 5-trisphosphate receptors (IP(3)Rs) [in particular, subtype 1 (IP(3)R1), and to a lesser extent subtype 2 (IP(3)R2) and subtype 3 (IP(3)R3)] all known as IP(3)-gated Ca(2+) channels. The phosphorylated IP(3)R1 (but not IP(3)R2 or IP(3)R3) is enhanced in its binding to IP(3) which subsequently stimulates IP(3)-mediated Ca(2+) flux. Transfection of the endothelial cells with ROK's PH cDNA significantly reduces ROK association with CD44v10, and effectively inhibits ROK-mediated phosphorylation of IP(3)Rs and IP(3)R-mediated Ca(2+) flux in vitro. The PH domain of ROK also functions as a dominant-negative mutant in vivo to block HA-dependent, CD44v10-specific intracellular Ca(2+) mobilization and endothelial cell migration. Taken together, we believe that CD44v10 interaction with ROK plays a pivotal role in IP(3)R-mediated Ca(2+) signaling during HA-mediated endothelial cell migration.
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Affiliation(s)
- Patrick A Singleton
- Department of Medicine, University of California San Francisco, Endocrine Unit (111N), San Francisco VA Medical Center, 94121, USA
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36
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Carter RW, Begaye M, Kanagy NL. Acute and chronic NOS inhibition enhances alpha(2)- adrenoreceptor-stimulated RhoA and Rho kinase in rat aorta. Am J Physiol Heart Circ Physiol 2002; 283:H1361-9. [PMID: 12234786 DOI: 10.1152/ajpheart.01101.2001] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We demonstrated that arteries from rats made hypertensive with chronic nitric oxide (NO) synthase (NOS) inhibition (N(omega)-nitro-L-arginine in drinking water, LHR) have enhanced contractile sensitivity to alpha(2)-adrenergic receptors (alpha(2)-AR) agonist UK-14304 compared with arteries from normotensive rats (NR). NO may regulate vascular tone in part through suppression of RhoA and Rho kinase (ROK). We hypothesized that enhanced RhoA and ROK activity augments alpha(2)-AR contraction in LHR aortic rings. Y-27632 eliminated UK-14304 contraction in LHR and NR aortic rings. The order of increasing sensitivity to Y-27632 was the following: endothelium-intact NR, LHR, and endothelium-denuded NR. UK-14304 stimulated RhoA translocation to the membrane fraction in LHR and denuded NR but not in intact NR aorta. Basally, more RhoA was present in the membrane fraction in denuded NR than in intact NR or LHR aorta. Relaxation to S-nitroso-N-acetyl-penicillamine and Y-27632 in denuded ionomycin-permeabilized rings was greater in NR than in LHR. Together these studies indicate alpha(2)-AR contraction depends on ROK activity more in NR than LHR aorta. Additionally, endogenous NO may regulate RhoA activation, whereas chronic NOS inhibition appears to cause RhoA desensitization.
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Affiliation(s)
- Rebecca W Carter
- Cell Biology and Physiology Department, University of New Mexico Health Sciences Center, Albuquerque 87131-5218, USA.
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37
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Arthur WT, Burridge K. RhoA inactivation by p190RhoGAP regulates cell spreading and migration by promoting membrane protrusion and polarity. Mol Biol Cell 2001; 12:2711-20. [PMID: 11553710 PMCID: PMC59706 DOI: 10.1091/mbc.12.9.2711] [Citation(s) in RCA: 365] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The binding of extracellular matrix proteins to integrins triggers rearrangements in the actin cytoskeleton by regulating the Rho family of small GTPases. The signaling events that mediate changes in the activity of Rho proteins in response to the extracellular matrix remain largely unknown. We have demonstrated in previous studies that integrin signaling transiently suppresses RhoA activity through stimulation of p190RhoGAP. Here, we investigated the biological significance of adhesion-dependent RhoA inactivation by manipulating p190RhoGAP signaling in Rat1 fibroblasts. The inhibition of RhoA activity that is induced transiently by adhesion was antagonized by expression of dominant negative p190RhoGAP. This resulted in impaired cell spreading on a fibronectin substrate, reduced cell protrusion, and premature assembly of stress fibers. Conversely, overexpression of p190RhoGAP augmented cell spreading. Dominant negative p190RhoGAP elevated RhoA activity in cells on fibronectin and inhibited migration, whereas overexpression of the wild-type GAP decreased RhoA activity, promoted the formation of membrane protrusions, and enhanced motility. Cells expressing dominant negative p190RhoGAP, but not control cells or cells overexpressing the wild-type GAP, were unable to establish polarity in the direction of migration. Taken together, these data demonstrate that integrin-triggered RhoA inhibition by p190RhoGAP enhances spreading and migration by regulating cell protrusion and polarity.
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Affiliation(s)
- W T Arthur
- Department of Cell and Developmental Biology, Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, NC 27599, USA.
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Kimura C, Oike M, Koyama T, Ito Y. Alterations of Ca2+ mobilizing properties in migrating endothelial cells. Am J Physiol Heart Circ Physiol 2001; 281:H745-54. [PMID: 11454579 DOI: 10.1152/ajpheart.2001.281.2.h745] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Endothelial migration is one of the major events of pathological neovascularization. We compared the characteristics of Ca2+ mobilization in nonconfluent, confluent, and migrating endothelial cells. Migration of endothelial cells was induced by wounding the confluent cell monolayer. The basal intracellular Ca2+ concentration was lower in migrating cells and higher in confluent cells than in nonconfluent cells. Thapsigargin (TG)-induced Ca2+ leak and TG-evoked Ca2+ entry were accelerated in migrating cells, whereas the latter was suppressed in confluent cells. The ATP-induced Ca2+ transient was also much larger in migrating cells than in confluent cells. These alterations were also observed in a cell as an intracellular polarization, i.e., the leading edge showed an acceleration of TG-evoked Ca2+ entry and an augmentation of the ATP-induced Ca2+ transient. Endothelial migration was significantly suppressed by TG or cyclopiazonic acid. These observations suggest that the alterations of Ca2+ store site-related Ca2+ mobilizations, i.e., Ca2+ sequestration, release, and TG-evoked Ca2+ entry, may be involved in the cellular mechanisms of endothelial migration.
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Affiliation(s)
- C Kimura
- Department of Pharmacology, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan
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Abstract
Throughout the entire process of cancer aetiology, progression and metastasis, the microenvironment of the local host tissue can be an active participant. Invasion occurs within a tumour-host microecology, where stroma and tumour cells exchange enzymes and cytokines that modify the local extracellular matrix, stimulate migration, and promote proliferation and survival. A new class of cancer therapies that targets this pathological communication interface between tumour cells and host cells is currently under development.
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Affiliation(s)
- L A Liotta
- Laboratory of Pathology, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland 20892, USA
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40
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Gupta N, Nodzenski E, Khodarev NN, Yu J, Khorasani L, Beckett MA, Kufe DW, Weichselbaum RR. Angiostatin effects on endothelial cells mediated by ceramide and RhoA. EMBO Rep 2001; 2:536-40. [PMID: 11415988 PMCID: PMC1083909 DOI: 10.1093/embo-reports/kve115] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Angiostatin is a cleavage product of plasminogen that has anti-angiogenic properties. We investigated whether the effects of angiostatin on endothelial cells are mediated by ceramide, a lipid implicated in endothelial cell signaling. Our results demonstrate that angiostatin produces a transient increase in ceramide that correlates with actin stress fiber reorganization, detachment and death. DNA array expression analysis performed on ceramide-treated human endothelial cells demonstrated induction of certain genes involved in cytoskeleton organization. Specifically, we report that treatment with angiostatin or ceramide results in the activation of RhoA, an important effector of cytoskeletal structure. We also show that treatment of endothelial cells with the antioxidant N-acetylcysteine abrogates morphological changes and cytotoxic effects of treatment with angiostatin or ceramide. These findings support a model in which angiostatin induces a transient rise in ceramide, RhoA activation and free radical production.
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Affiliation(s)
- N Gupta
- Department of Surgery, University of Chicago, MC 9006, 5758 South Maryland Avenue, Chicago, IL 60637, USA
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Abstract
Angiogenesis, the formation of new vessels from pre-existing vasculature, is critical to ascites development and metastasis in ovarian cancer. Many growth factors important to ovarian cancer invasion are also prominent in its associated angiogenesis. Deregulation of normal angiogenic processes occurs with the cancer's acquisition of the ability to secrete pro-angiogenic factors. The local imbalance of endogenous angio-stimulators and angio-inhibitors promotes vascularization and vascular leak. Assessment of these pro-angiogenic growth factors and enumeration of tumour-associated microvessels have been shown to be prognosticators of ovarian cancer outcome, and may also be surrogates of ovarian cancer tumour burden and/or ascites formation. The process of angiogenesis has been targeted for therapeutics development. Ovarian cancer is a primary cancer against which these new agents are being tested. Thus, further understanding of the molecular and cell biology of angiogenesis in the context of ovarian cancer offers important directions for estimation of patient outcome and for patient treatment.
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Affiliation(s)
- M R Brown
- Molecular Signaling Section, Laboratory of Pathology, National Cancer Institute, Bethesda, MD 20892, USA
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42
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Lee OH, Lee DJ, Kim YM, Kim YS, Kwon HJ, Kim KW, Kwon YG. Sphingosine 1-phosphate stimulates tyrosine phosphorylation of focal adhesion kinase and chemotactic motility of endothelial cells via the G(i) protein-linked phospholipase C pathway. Biochem Biophys Res Commun 2000; 268:47-53. [PMID: 10652210 DOI: 10.1006/bbrc.2000.2087] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have previously shown that sphingosine 1-phosphate (S1P) stimulates motility of human umbilical vein endothelial cells (HUVECs) (O.-H. Lee et al., Biochem. Biophys. Res. Commun. 264, 743-750, 1999). To investigate the molecular mechanisms by which S1P stimulates HUVEC motility, we examined tyrosine phosphorylation of p125 focal adhesion kinase (p125(FAK)) which is important for cell migration. S1P induces a rapid increase in tyrosine phosphorylation of p125(FAK). Compared with other structurally related lipid metabolites such as sphingosine, C2-ceramide, and lysophosphatidic acid, S1P uniquely stimulated p125(FAK) tyrosine phosphorylation and migration of HUVECs. The effect of S1P on p125(FAK) tyrosine phosphorylation was markedly reduced by treatment with pertussis toxin or U73122, a phospholipase C (PLC) inhibitor. As a downstream signal of PLC, p125(FAK) tyrosine phosphorylation in response to S1P was totally blocked by depletion of the intracellular calcium pool. However, protein kinase C (PKC) inhibitor had no effect on the response to S1P. Finally, chemotaxis assays revealed that inhibition of PLC but not PKC significantly abrogated S1P-stimulated HUVEC migration. These results suggest that the G(i)-coupled receptor-mediated PLC-Ca(2+) signaling pathway may be importantly involved in S1P-stimulated focal adhesion formation and migration of endothelial cells.
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Affiliation(s)
- O H Lee
- Institute of Environment and Life Science, Hallym Academy of Science, Hallym University, Kangwon-Do, Chunchon, 200-702, Korea
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