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Yao L, Xu Z, Davies DE, Jones MG, Wang Y. Dysregulated bidirectional epithelial-mesenchymal crosstalk: a core determinant of lung fibrosis progression. CHINESE MEDICAL JOURNAL PULMONARY AND CRITICAL CARE MEDICINE 2024; 2:27-33. [PMID: 38558961 PMCID: PMC7615773 DOI: 10.1016/j.pccm.2024.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Progressive lung fibrosis is characterised by dysregulated extracellular matrix (ECM) homeostasis. Understanding of disease pathogenesis remains limited and has prevented the development of effective treatments. While an abnormal wound healing response is strongly implicated in lung fibrosis initiation, factors that determine why fibrosis progresses rather than regular tissue repair occurs are not fully explained. Within human lung fibrosis there is evidence of altered epithelial and mesenchymal lung populations as well as cells undergoing epithelial-mesenchymal transition (EMT), a dynamic and reversible biological process by which epithelial cells lose their cell polarity and down-regulate cadherin-mediated cell-cell adhesion to gain migratory properties. This review will focus upon the role of EMT and dysregulated epithelial-mesenchymal crosstalk in progressive lung fibrosis.
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Affiliation(s)
- Liudi Yao
- Biological Sciences, Faculty of Environmental and Life Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Zijian Xu
- Biological Sciences, Faculty of Environmental and Life Sciences, University of Southampton, Southampton SO17 1BJ, UK
| | - Donna E. Davies
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton SO16 6YD, UK
- Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK
- NIHR Southampton Biomedical Research Centre, University Hospital Southampton, Southampton SO16 6YD, UK
| | - Mark G. Jones
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton SO16 6YD, UK
- Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK
- NIHR Southampton Biomedical Research Centre, University Hospital Southampton, Southampton SO16 6YD, UK
| | - Yihua Wang
- Biological Sciences, Faculty of Environmental and Life Sciences, University of Southampton, Southampton SO17 1BJ, UK
- Institute for Life Sciences, University of Southampton, Southampton SO17 1BJ, UK
- NIHR Southampton Biomedical Research Centre, University Hospital Southampton, Southampton SO16 6YD, UK
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2
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Yao L, Zhou Y, Li J, Wickens L, Conforti F, Rattu A, Ibrahim FM, Alzetani A, Marshall BG, Fletcher SV, Hancock D, Wallis T, Downward J, Ewing RM, Richeldi L, Skipp P, Davies DE, Jones MG, Wang Y. Bidirectional epithelial-mesenchymal crosstalk provides self-sustaining profibrotic signals in pulmonary fibrosis. J Biol Chem 2021; 297:101096. [PMID: 34418430 PMCID: PMC8435701 DOI: 10.1016/j.jbc.2021.101096] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 08/06/2021] [Accepted: 08/17/2021] [Indexed: 11/11/2022] Open
Abstract
Idiopathic pulmonary fibrosis (IPF) is the prototypic progressive fibrotic lung disease with a median survival of 2 to 4 years. Injury to and/or dysfunction of the alveolar epithelium is strongly implicated in IPF disease initiation, but the factors that determine whether fibrosis progresses rather than normal tissue repair occurs remain poorly understood. We previously demonstrated that zinc finger E-box-binding homeobox 1-mediated epithelial-mesenchymal transition in human alveolar epithelial type II (ATII) cells augments transforming growth factor-β-induced profibrogenic responses in underlying lung fibroblasts via paracrine signaling. Here, we investigated bidirectional epithelial-mesenchymal crosstalk and its potential to drive fibrosis progression. RNA-Seq of lung fibroblasts exposed to conditioned media from ATII cells undergoing RAS-induced epithelial-mesenchymal transition identified many differentially expressed genes including those involved in cell migration and extracellular matrix regulation. We confirmed that paracrine signaling between RAS-activated ATII cells and fibroblasts augmented fibroblast recruitment and demonstrated that this involved a zinc finger E-box-binding homeobox 1-tissue plasminogen activator axis. In a reciprocal fashion, paracrine signaling from transforming growth factor-β-activated lung fibroblasts or IPF fibroblasts induced RAS activation in ATII cells, at least partially through the secreted protein acidic and rich in cysteine, which may signal via the epithelial growth factor receptor via epithelial growth factor-like repeats. Together, these data identify that aberrant bidirectional epithelial-mesenchymal crosstalk in IPF drives a chronic feedback loop that maintains a wound-healing phenotype and provides self-sustaining profibrotic signals.
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Affiliation(s)
- Liudi Yao
- Biological Sciences, Faculty of Environmental and Life Sciences, University of Southampton, Southampton, United Kingdom
| | - Yilu Zhou
- Biological Sciences, Faculty of Environmental and Life Sciences, University of Southampton, Southampton, United Kingdom; Institute for Life Sciences, University of Southampton, Southampton, United Kingdom
| | - Juanjuan Li
- Biological Sciences, Faculty of Environmental and Life Sciences, University of Southampton, Southampton, United Kingdom
| | - Leanne Wickens
- Centre for Proteomic Research, Institute for Life Sciences, University of Southampton, Southampton, United Kingdom; Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom; NIHR Southampton Biomedical Research Centre, University Hospital Southampton, Southampton, United Kingdom
| | - Franco Conforti
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom; NIHR Southampton Biomedical Research Centre, University Hospital Southampton, Southampton, United Kingdom
| | - Anna Rattu
- Biological Sciences, Faculty of Environmental and Life Sciences, University of Southampton, Southampton, United Kingdom
| | - Fathima Maneesha Ibrahim
- Biological Sciences, Faculty of Environmental and Life Sciences, University of Southampton, Southampton, United Kingdom
| | - Aiman Alzetani
- NIHR Southampton Biomedical Research Centre, University Hospital Southampton, Southampton, United Kingdom; University Hospital Southampton, Southampton, United Kingdom
| | - Ben G Marshall
- NIHR Southampton Biomedical Research Centre, University Hospital Southampton, Southampton, United Kingdom; University Hospital Southampton, Southampton, United Kingdom
| | - Sophie V Fletcher
- NIHR Southampton Biomedical Research Centre, University Hospital Southampton, Southampton, United Kingdom; University Hospital Southampton, Southampton, United Kingdom
| | - David Hancock
- Oncogene Biology, The Francis Crick Institute, London, United Kingdom
| | - Tim Wallis
- NIHR Southampton Biomedical Research Centre, University Hospital Southampton, Southampton, United Kingdom; University Hospital Southampton, Southampton, United Kingdom
| | - Julian Downward
- Oncogene Biology, The Francis Crick Institute, London, United Kingdom
| | - Rob M Ewing
- Biological Sciences, Faculty of Environmental and Life Sciences, University of Southampton, Southampton, United Kingdom; Institute for Life Sciences, University of Southampton, Southampton, United Kingdom
| | - Luca Richeldi
- Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom; NIHR Southampton Biomedical Research Centre, University Hospital Southampton, Southampton, United Kingdom; Unità Operativa Complessa di Pneumologia, Università Cattolica del Sacro Cuore, Fondazione Policlinico A. Gemelli, Rome, Italy
| | - Paul Skipp
- Biological Sciences, Faculty of Environmental and Life Sciences, University of Southampton, Southampton, United Kingdom; Institute for Life Sciences, University of Southampton, Southampton, United Kingdom; Centre for Proteomic Research, Institute for Life Sciences, University of Southampton, Southampton, United Kingdom
| | - Donna E Davies
- Institute for Life Sciences, University of Southampton, Southampton, United Kingdom; Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom; NIHR Southampton Biomedical Research Centre, University Hospital Southampton, Southampton, United Kingdom
| | - Mark G Jones
- Institute for Life Sciences, University of Southampton, Southampton, United Kingdom; Clinical and Experimental Sciences, Faculty of Medicine, University of Southampton, Southampton, United Kingdom; NIHR Southampton Biomedical Research Centre, University Hospital Southampton, Southampton, United Kingdom.
| | - Yihua Wang
- Biological Sciences, Faculty of Environmental and Life Sciences, University of Southampton, Southampton, United Kingdom; Institute for Life Sciences, University of Southampton, Southampton, United Kingdom; NIHR Southampton Biomedical Research Centre, University Hospital Southampton, Southampton, United Kingdom.
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3
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Jaiswal RK, Varshney AK, Yadava PK. Diversity and functional evolution of the plasminogen activator system. Biomed Pharmacother 2018; 98:886-898. [PMID: 29571259 DOI: 10.1016/j.biopha.2018.01.029] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 12/29/2017] [Accepted: 01/03/2018] [Indexed: 01/08/2023] Open
Abstract
The urokinase plasminogen activator system is a family of serine proteases which consists of uPA (urokinase plasminogen activator), uPAR (urokinase type plasminogen activator receptor) and PAI-1 (plasminogen activator inhibitor 1). In addition to their significant roles in activation, these proteases act as key regulators of the tumor microenvironment and are involved in the metastatic process in many cancers. High levels of uPA system proteases in many human cancer predicts poor patient prognosis and strongly indicated a key role of uPA system in cancer metastasis. Individual components of uPA system are found to be differentially expressed in cancer cells compared to normal cells and therefore are potential therapeutic targets. In this review, we present the molecular and cellular mechanisms underlying the role of uPA system in cancer progression. Epithelial to mesenchymal transitions (EMT) is the main cause of the cancer cell metastasis. We have also attempted to relate the role of uPA signaling in EMT of cancer cells.
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Affiliation(s)
- Rishi Kumar Jaiswal
- Applied Molecular Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Akhil Kumar Varshney
- Applied Molecular Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India
| | - Pramod Kumar Yadava
- Applied Molecular Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India.
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Odaka T, Kobayashi K, Takahashi K, Nakamura H, Matsuoka T. Effect of prostaglandin E2 on urokinase-type plasminogen activator production by human lung fibroblasts. Scandinavian Journal of Clinical and Laboratory Investigation 2009; 69:225-33. [PMID: 18949628 DOI: 10.1080/00365510802478294] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Human lung fibroblasts are components of stromal tissue and produce various proteins as occasion demands, such as extracellular matrix (ECM) components and proteases. Pulmonary tumour cells produce high levels of prostaglandin E(2) (PGE(2)), which regulates tumour growth and metastasis. Urokinase-type plasminogen activator (uPA) is essential in the degradation of peritumour ECM. Furthermore, uPA is an important protease believed responsible for several tumour characteristics through its activation of certain proteases and growth factors. We hypothesized that the PGE(2) overexpression from tumour cells would have some effect on uPA expression in lung fibroblasts. In this study, the influence of PGE(2) on uPA expression in human lung fibroblasts was investigated using two lines of such fibroblasts. Although the cell surface uPA level was comparable to that of PGE(2) untreated cells, the expression of uPA mRNA and production was increased by the addition of PGE(2) in both lines of fibroblasts. These fibroblasts expressed both the EP(2) and EP(4) PGE(2) receptor mRNAs. Pretreatment with EP(2) and/or EP(4) receptor antagonists reduced the intercellular and cell surface uPA expression of the human lung fibroblasts. These results indicated that there is a relationship between the PGE(2) system and uPA production in human lung fibroblasts operating through EP(2) and/or EP(4) receptor signalling. uPA induced by PGE(2) from stromal fibroblasts surrounding lung tumour thus appears to play an important role through these EP receptors. Inhibition of EPs in tumour tissue might be a useful strategy for anti-metastasis therapy.
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Affiliation(s)
- Tomotada Odaka
- Tokyo Medical University Kasumigaura Hospital, Fifth Department of Internal Medicine, Ami, Inashiki, Ibaraki, Japan.
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5
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BECHTEL MJ, SCHAEFER BM, KRAMER MD. Plasminogen activator inhibitor type-2 in the lesional epidermis of lupus erythematosus. Br J Dermatol 2008. [DOI: 10.1046/j.1365-2133.1996.24759.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Plekhanova OS, Stepanova VV, Ratner EI, Bobik A, Tkachuk VA, Parfyonova YV. Urokinase plasminogen activator in injured adventitia increases the number of myofibroblasts and augments early proliferation. J Vasc Res 2006; 43:437-46. [PMID: 16899994 DOI: 10.1159/000094906] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2005] [Accepted: 06/12/2006] [Indexed: 11/19/2022] Open
Abstract
Myofibroblasts are involved in vessel remodeling during the development of hypertension as well as after angioplasty and aortocoronary grafting, but the mechanisms of myofibroblastic phenotypic modulation are not fully elucidated. We assessed the role of urokinase plasminogen activator (uPA) and its proteolytic activity in myofibroblast differentiation and the early proliferation following mechanical injury of the rat carotid adventitia. The effects of perivascular application of recombinant uPA (r-uPA), proteolytically inactive r-uPA(H/Q) and uPA neutralizing antibody were evaluated 4 days after surgical injury to the adventitia. The phenotype of adventitial cells was assessed using anti-alpha-smooth muscle actin (alpha-SM actin) antibody, anti-SM heavy chain myosin, anti-high-molecular-weight caldesmon, anti-smoothelin and anti-ED-1 antibodies, proliferation by the expression of proliferating cell nuclear antigen, and the size of the adventitia by quantitative morphometry. Four days after injury, the intensive immunostaining for urokinase appeared in the rat carotid artery adventitia. At the same time, the frequency of alpha-SM actin-positive adventitial cells was 1.8+/-1.1% in uninjured arteries and 25.2+/-5.4% in injured arteries (p<0.05), and the respective frequency of ED-1-positive cells 1.5+/-1.1 and 25.0+/-5.2%. The application of exogenous r-uPA doubled the numbers of alpha-SM actin-positive adventitial cells to 55.7+/-6.8% (p<0.05). ED-1-positive cells and proliferating cell nuclear antigen-positive cells as well as the size of the adventitia were also significantly increased after r-uPA compared with injury alone. In contrast, the proteolytically inactive r-uPA(H/Q) did not affect any parameters. The application of uPA neutralizing antibody attenuated the frequency of alpha-SM actin-positive cells to 12.6+/-3.5% (p<0.05), the frequency of ED-1-positive cells, and the numbers of adventitial cells. r-uPA stimulation of cultured human skin fibroblasts significantly increased the alpha-SM actin content in a concentration-dependent manner. In contrast, r-uPAH/Q did not induce changes in alpha-SM actin content. We conclude that uPA, which is upregulated in the injured adventitia, can augment adventitial cell accumulation, including myofibroblasts, and adventitia growth early after injury of the rat carotid artery adventitia by mechanisms involving proteolysis.
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Roychoudhury PK, Khaparde SS, Mattiasson B, Kumar A. Synthesis, regulation and production of urokinase using mammalian cell culture: a comprehensive review. Biotechnol Adv 2006; 24:514-28. [PMID: 16822639 DOI: 10.1016/j.biotechadv.2006.05.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2006] [Revised: 05/17/2006] [Accepted: 05/20/2006] [Indexed: 11/19/2022]
Abstract
Urokinase, a serine protease, catalyzes the conversion of plasminogen to plasmin, which is responsible for dissolution of clots in blood vessels. It is an important drug for treatment of thromboembolic disease. Production of urokinase by mammalian cell culture has the following important steps: synthesis, regulation and secretion. Production and accumulation of this product in a bioreactor is a real challenge for biochemical engineers. Considerable information at molecular level needs to be understood for production of urokinase in order to correlate different parameters, which in turn can maximize the productivity. This information will be highlighted in this review. Moreover, urokinase production is a product-inhibited process. Therefore, in situ urokinase separation strategy is required to operate a bioreactor at its maximum urokinase formation rate. Integrated urokinase production and isolation processes developed recently will also be discussed briefly in this review.
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Affiliation(s)
- Pradip K Roychoudhury
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology, Hauz Khas, New Delhi 110 016, India
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Legrand C, Polette M, Tournier JM, de Bentzmann S, Huet E, Monteau M, Birembaut P. uPA/plasmin system-mediated MMP-9 activation is implicated in bronchial epithelial cell migration. Exp Cell Res 2001; 264:326-36. [PMID: 11262189 DOI: 10.1006/excr.2000.5125] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
To examine the effects of the uPA/plasmin system on cell migration in relation to the activation of MMP-9, we used ex vivo and in vitro wound-repair models of human bronchial epithelial cells and videomicroscopy techniques that make possible cell tracking and quantification of cell migration speeds. We observed that uPA was only detected in migrating cells at the wound edges and located at crucial sites for cell/extracellular matrix interactions. The implication of uPA in human bronchial epithelial cell migration was studied by incubating cultures with a monoclonal antibody raised against uPA and these experiments led to a 70% reduction in cell velocity. To examine the effects of the plasmin system on cell migration, we incubated cultures with increasing concentrations of plasmin or activated MMP-9. We observed a significant dose-dependent increase in cell migration velocity with plasmin (P < 0.001) and MMP-9 (P < 0.001). Moreover, addition of exogenous plasmin led to a twofold increase of activated MMP-9 in migrating cells. We also demonstrated that the addition of anti-uPA IgG led to an inhibition of 43% of activated MMP-9. In conclusion, these results show that uPA is involved in human bronchial epithelial cells migration. This action is mediated by the generation of plasmin, which in turn activates MMP-9, thus making possible cell migration.
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Affiliation(s)
- C Legrand
- Laboratoire Pol Bouin-CHU, INSERM Unité 514, IFR 53, and, Reims, France
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9
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Description of the plasminogen activating system in canine gingival crevicular fluid. ACTA ACUST UNITED AC 2000. [DOI: 10.1054/fipr.2000.0091] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Kinnby B, Lindberg P, Lecander I, Matsson L. Localization of plasminogen activators and plasminogen-activator inhibitors in human gingival tissues demonstrated by immunohistochemistry and in situ hybridization. Arch Oral Biol 1999; 44:1027-34. [PMID: 10669081 DOI: 10.1016/s0003-9969(99)00098-9] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The plasminogen-activating system plays an important part in tissue proteolysis in physiological as well as pathological processes. Plasminogen activators u-PA (urokinase) and t-PA (tissue) as well as the inhibitors PAI-1 and PAI-2 are present in gingival crevicular fluid in concentrations significantly greater than in plasma. This fact, and the finding that the concentrations of t-PA and PAI-2 are higher in areas with gingival inflammation, indicate local production of these components. The present study describes, by means of in situ hybridization and immunohistochemistry, the localization of the plasminogen activators and their inhibitors in gingival tissues from patients undergoing periodontal surgery. t-PA mRNA and t-PA antigen were primarily found in the epithelial tissues, predominantly in the sulcular and junctional regions, although occasionally in the oral epithelium and in blood vessels of the connective tissue. u-PA and u-PA-receptor signals were seen in single cells within the junctional and sulcular epithelia and adjacent to blood vessels close to the junctional epithelium, but rarely in the oral epithelium. Similar to t-PA, the predominant location of PAI-2 mRNA was the gingival epithelia. In the junctional and sulcular epithelia, PAI-2 mRNA was seen throughout the thickness, while in the oral epithelium the strongest signals were seen in stratum granulosum and stratum spinosum. PAI-1 mRNA was invariably found in the connective tissue associated with blood vessels. The present study confirms earlier indications of local production of plasminogen activators and their inhibitors in gingival tissues. In addition, the results demonstrate that t-PA and PAI-2 in these patients are produced predominantly in the epithelial tissues. Furthermore, the presence of t-PA and PAI-2 seems to be most pronounced in the areas likely to be subjected to bacterial assault.
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Affiliation(s)
- B Kinnby
- Center for Oral Health Sciences, Malmö University, Sweden
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11
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Yebra M, Goretzki L, Pfeifer M, Mueller BM. Urokinase-type plasminogen activator binding to its receptor stimulates tumor cell migration by enhancing integrin-mediated signal transduction. Exp Cell Res 1999; 250:231-40. [PMID: 10388537 DOI: 10.1006/excr.1999.4510] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Urokinase-type plasminogen activator (uPA) and its receptor (uPAR) participate in matrix degradation and cell migration by focusing proteolysis and functioning as a signaling ligand/receptor complex. uPAR, anchored by a lipid moiety in the membrane, is thought to require a transmembrane adapter to transduce signals into the cytoplasm. To study uPAR signaling, we transfected the prostate carcinoma cell line LNCaP, which does not express endogenous uPA or uPAR, with a uPAR encoding cDNA, resulting in high-level surface expression. We studied migration of these cells on fibronectin, which is mediated by the integrin alpha5beta1. Ligation of uPAR with uPA or its amino-terminal fragment enhanced haptotactic migration to fibronectin. In cells on fibronectin, but not on poly-l-lysine, ligation of uPAR also resulted in tyrosine phosphorylation of several proteins, including two proteins involved in integrin signaling, focal adhesion kinase and the crk-associated substrate p130(Cas). Furthermore, after uPAR ligation, uPAR was co-immunoprecipitated with beta1 integrins from the detergent-insoluble fraction of cell lysates. Thus, our data suggest that uPAR occupancy results in an interaction between uPAR and integrins and a potentiation of integrin-mediated signaling, which leads to enhanced cell migration.
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Affiliation(s)
- M Yebra
- Department of Immunology, The Scripps Research Institute, 10550 North Torrey Pines Road, IMM13, La Jolla, California, 92037, USA
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Gordon SR, DeMoss J. Exposure to lysosomotropic amines and protease inhibitors retard corneal endothelial cell migration along the natural basement membrane during wound repair. Exp Cell Res 1999; 246:233-42. [PMID: 9882532 DOI: 10.1006/excr.1998.4298] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Regulation of cell migration along the natural basement membrane during wound repair in the organ culture corneal endothelium was investigated using various lysosomotropic amines and protease inhibitors. Following a circular transcorneal freeze injury, cells within the area die and expose the underlying basement membrane (Descemet's membrane). During normal wound repair, cells traverse this expanse and repopulate the region by approximately 48 h postinjury. During this time, acid phosphatase histochemistry revealed distinct alterations in the lysosomal population of cells that were adjacent to, and migrated into, the wound region. To explore whether relationships may exist between changes in the lysosome population and cell migration, injured endothelia were organ cultured in the presence of either methylamine or chloroquine, two lysosomotropic amines. Methylamine significantly retarded cell translocation (85%) into the injury zone when compared to nontreated controls. In comparison, chloroquine was less effective in restricting injury-induced cell migration and propylamine, also a lysosomotropic amine, had no influence on the repair process. In addition, two serine/thio protease inhibitors, leupeptin and antipain, were both able to impede cell translocation during wound repair by 85 and 52%, respectively, whereas soybean trypsin inhibitor, a serine protease inhibitor, exhibited no inhibitory effect on the repair process. Similarly, incubating injured tissues in either 1,10-phenanthroline or phosphoramidon, both metalloproteinase inhibitors, did not prevent endothelial cell movement nor wound repair. Results indicate that corneal endothelial cell migration along the natural basement membrane is dependent on protease function. Although the precise nature of the proteases involved has yet to be ascertained, results indicate that lysosomal enzymes may have a distinct role in corneal endothelial cell movement along the natural basement membrane during wound repair.
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Affiliation(s)
- S R Gordon
- Department of Biological Sciences, Oakland University, Rochester, Michigan, 48309-4476, USA.
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13
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Parry MA, Fernandez-Catalan C, Bergner A, Huber R, Hopfner KP, Schlott B, Gührs KH, Bode W. The ternary microplasmin-staphylokinase-microplasmin complex is a proteinase-cofactor-substrate complex in action. NATURE STRUCTURAL BIOLOGY 1998; 5:917-23. [PMID: 9783753 DOI: 10.1038/2359] [Citation(s) in RCA: 122] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The serine proteinase plasmin is the key fibrinolytic enzyme that dissolves blood clots and also promotes cell migration and tissue remodeling. Here, we report the 2.65 A crystal structure of a ternary complex of microplasmin-staphylokinase bound to a second microplasmin. The staphylokinase 'cofactor' does not affect the active-site geometry of the plasmin 'enzyme', but instead modifies its subsite specificity by providing additional docking sites for enhanced presentation of the plasminogen 'substrate' to the 'enzymes's' active site. The activation loop of the plasmin 'substrate', cleaved in these crystals, can be reconstructed to show how it runs across the active site of the plasmin 'enzyme' prior to activation cleavage. This is the first experimental structure of a productive proteinase-cofactor-macromolecular substrate complex. Furthermore, it provides a template for the design of improved plasminogen activators and plasmin inhibitors with considerable therapeutical potential.
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Affiliation(s)
- M A Parry
- Max-Planck Institute of Biochemistry, Department for Structural Research, Martinsried, Germany.
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14
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Bator JM, Cohen RL, Chambers DA. Hydrocortisone regulates the dynamics of plasminogen activator and plasminogen activator inhibitor expression in cultured murine keratinocytes. Exp Cell Res 1998; 242:110-9. [PMID: 9665808 DOI: 10.1006/excr.1998.4065] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The plasminogen activators tPA and uPA, and their inhibitors, PAI-1 and PAI-2, have been associated with epithelial homeostasis and wound healing. In these studies, we investigate the effect of the steroid hormone hydrocortisone, a commonly used therapeutic modality for skin, on PAs/PAIs in serum- and plasminogen-free primary cultures of murine keratinocytes. SDS-PAGE fibrin zymography showed that addition of 1 microM hydrocortisone to cultures significantly reduced tPA fibrinolytic activity in both cell extracts and conditioned medium. uPA activity in conditioned medium was similarly inhibited. Cells were also cultured in the presence of dibutyryl cyclic AMP (dbcAMP). dbcAMP (5 mM) alone enhanced uPA and tPA fibrinolytic activity in conditioned medium, but this increase was diminished in the presence of 1 microM hydrocortisone. Immunoblots revealed a three- to fivefold induction of free PAI-1 by hydrocortisone which was partially blocked by dbcAMP. Northern blots showed that PAI-1 mRNA increased threefold 2 h after addition of hydrocortisone and remained elevated at least 8 h. In contrast, uPA and tPA mRNA were unchanged over the same time course. uPA, tPA, and PAI-1 mRNA increased in the presence of dbcAMP; levels remained elevated at least 8 h. HC suppressed the induction of uPA and tPA by dbcAMP. Studies directed at identifying plasminogen mRNA showed that in this culture system, keratinocytes produce no plasminogen mRNA either in the presence or in the absence of hydrocortisone or dbcAMP. Collectively, these results show that keratinocyte plasminogen activator activity is suppressed by hydrocortisone as a function of increased PAI-1 combined with an attenuation of PA induction by agents that increase intracellular cAMP. These results provide additional information to further define the mechanism by which glucocorticoids inhibit wound healing.
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Affiliation(s)
- J M Bator
- Center for Molecular Biology of Oral Diseases, University of Illinois at Chicago, Illinois 60612, USA
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15
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Hatane T, Yoshida E, Kawano J, Sugiki M, Onitsuka T, Maruyama M. Prostaglandin I2 analog enhances the expression of urokinase-type plasminogen activator and wound healing in cultured human fibroblast. BIOCHIMICA ET BIOPHYSICA ACTA 1998; 1403:189-98. [PMID: 9630624 DOI: 10.1016/s0167-4889(98)00041-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
This study examines the effects of prostaglandin I2 (PGI2) on urokinase-type plasminogen activator (uPA) production and wound healing by human fibroblasts. Employing fibrin autography, it was found that beraprost sodium, a stable PGI2 analog, enhanced the fibrinolytic activity in media conditioned by human fibroblasts, TIG-3-20 cells. Fibrin zymography, ELISA, and Northern blot analysis confirmed that the enhanced activity was caused by an increase in uPA synthesis and secretion and a decrease in type-1 plasminogen activator inhibitor. While cycloheximide and 2',5'-dideoxyadenosine, an adenylate cyclase inhibitor, suppressed the effect of PGI2, dibutyryl cyclic AMP increased the fibrinolytic activity and uPA mRNA. These findings indicate that PGI2 promotes uPA production in TIG-3-20 cells via direct stimulation of the cyclic AMP intracellular pathway. A similar effect was observed in two other fibroblast cell lines, TIG-7-20 and TIG-7-30. Although PGI2 itself did not affect cellular proliferation, it promoted in vitro repopulation of the denuded area in a wounded monolayer. These observations suggest that PGI2 can stimulate wound healing through the enhanced production of uPA.
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Affiliation(s)
- T Hatane
- Department of Physiology, Miyazaki Medical College, 5200 Kihara, Kiyotake, Miyazaki 889-16, Japan.
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16
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Hrzenjak T, Popović M, Bozić T, Grdisa M, Kobrehel D, Tiska-Rudman L. Fibrinolytic and anticoagulative activities from the earthworm Eisenia foetida. Comp Biochem Physiol B Biochem Mol Biol 1998; 119:825-32. [PMID: 9787773 DOI: 10.1016/s0305-0491(98)00060-1] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Biologically active glycolipoprotein complex (G-90) isolated from whole earthworm tissue extract shows anticoagulative and fibrinolytic activities. We isolated two tyrosine like serine peptidases with molecular masses of 34 kDa (P I) and 23 kDa (P II), respectively. P I peptidase is autocatalytically degraded to P II. Both peptidases exhibit fibrinolytic and anticoagulative activities. The activity of P I is much higher. P I in concentration of 10(5) ng ml-1 of plasma shortened the physiological time of fibrin clot lysis by 54% and completely inhibited blood clotting at a concentration of 10(3) ng ml-1 of venous blood.
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Affiliation(s)
- T Hrzenjak
- Department of Biology, Faculty of Veterinary Medicine, University of Zagreb, Croatia
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17
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Wakita H, Matsushita K, Nishimura K, Tokura Y, Furukawa F, Takigawa M. Sphingosylphosphorylcholine stimulates proliferation and upregulates cell surface-associated plasminogen activator activity in cultured human keratinocytes. J Invest Dermatol 1998; 110:253-8. [PMID: 9506444 DOI: 10.1046/j.1523-1747.1998.00120.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Of the various sphingolipid metabolites, including sphingosine, sphingosylphosphorylcholine (SPC), dimethylsphingosine, sphingosine-1-phosphate, N-acetylsphingosine, and skin-specific ceramides, only SPC accelerated cutaneous wound healing in full-thickness excision wounds in genetically healing-impaired diabetic (db/db) mice. A histologic examination revealed that SPC promoted not only granulation tissue formation, but also the re-epithelization of epidermal keratinocytes. As the direct effects of SPC on keratinocytes are completely unknown, we investigated the effects of SPC on normal cultured human keratinocytes. SPC concentration-dependently enhanced DNA synthesis in keratinocytes, with an increase in intracellular calcium concentrations due to the release of calcium ions from intracellular stores. SPC upregulated cell surface plasminogen activity, and at the same time increased the cell surface expression of urokinase-type plasminogen activator (uPA) and urokinase-type plasminogen activator-receptor (uPA-R) in keratinocytes. Furthermore, SPC promoted the in vitro wound repair of cultured keratinocytes, which was partially blocked by an anti-uPA monoclonal antibody. Our results suggest that one of the mechanisms responsible for the SPC-mediated promotion of cutaneous wound healing seems to be an enhancement of re-epithelization caused by the direct stimulation of the proliferation of keratinocytes, and an activation of the uPA/uPA-R system, which enhances the migration of keratinocytes.
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Affiliation(s)
- H Wakita
- Department of Dermatology, Hamamatsu University School of Medicine, Japan
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18
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Abstract
The urokinase-type plasminogen activator (u-PA) system consists of the serine proteinases plasmin and u-PA; the serpin inhibitors alpha2-anti-plasmin, PAI-1 and PAI-2; and the u-PA receptor (u-PAR). Two lines of evidence have strongly suggested an important and apparently causal role for the u-PA system in cancer metastasis: results from experimental model systems with animal tumor metastasis and the finding that high levels of u-PA, PAI-1 and u-PAR in many tumor types predict poor patient prognosis. We discuss here recent observations related to the molecular and cellular mechanisms underlying this role of the u-PA system. Many findings suggest that the system does not support tumor metastasis by the unrestricted enzyme activity of u-PA and plasmin. Rather, pericellular molecular and functional interactions between u-PA, u-PAR, PAI-1, extracellular matrix proteins, integrins, endocytosis receptors and growth factors appear to allow temporal and spatial re-organizations of the system during cell migration and a selective degradation of extracellular matrix proteins during invasion. Differential expression of components of the system by cancer and non-cancer cells, regulated by paracrine mechanisms, appear to determine the involvement of the system in cancer cell-directed tissue remodeling. A detailed knowledge of these processes is necessary for utilization of the therapeutic potential of interfering with the action of the system in cancers.
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Affiliation(s)
- P A Andreasen
- Department of Molecular and Structural Biology, University of Aarhus, Denmark.
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Kjøller L, Kanse SM, Kirkegaard T, Rodenburg KW, Rønne E, Goodman SL, Preissner KT, Ossowski L, Andreasen PA. Plasminogen activator inhibitor-1 represses integrin- and vitronectin-mediated cell migration independently of its function as an inhibitor of plasminogen activation. Exp Cell Res 1997; 232:420-9. [PMID: 9168821 DOI: 10.1006/excr.1997.3540] [Citation(s) in RCA: 182] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Cell migration involves the integrins, their extracellular matrix ligands, and pericellular proteolytic enzyme systems. We have studied the role of plasminogen activator inhibitor-1 (PAI-1) in cell migration, using human amnion WISH cells and human epidermoid carcinoma HEp-2 cells in an assay measuring migration from microcarrier beads and a modified Boyden-chamber assay. Active, but not latent or reactive center-cleaved, PAI-1 inhibited migration. A PAI-1 mutant without ability to inhibit plasminogen activation was as active as wild-type PAI-1 as a migration inhibitor, showing that inhibition of plasminogen activation was not involved. PAI-1 specifically interfered with intergrin- and vitronectin-mediated migration: Migration onto vitronectin-coated but not onto fibronectin-coated surfaces was inhibited by PAI-1, a cyclic RGD peptide inhibited migration, and both cell lines expressed vitronectin-binding alpha v-integrins. In addition, active PAI-1, but not latent or reactive center-cleaved PAI-1, inhibited vitronectin binding to integrins in an in vitro binding assay, without affecting binding of fibronectin. Monoclonal antibodies against the urokinase receptor, another vitronectin binding protein, did not affect cell migration in the beads assay, while some inhibitory effect was observed in the Boyden-chamber assay. We conclude that PAI-1, independently of its role as a proteinase inhibitor, inhibits cell migration by competing for vitronectin binding to integrins, while the interference of PAI-1 with binding of vitronectin to the urokinase receptor may play a secondary role. These data define a novel function for the serpin PAI-1, enabling it to regulate cell migration over vitronectin-rich extracellular matrix in the body.
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Affiliation(s)
- L Kjøller
- Department of Molecular and Structural Biology, University of Arhus, Denmark
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Bizik J, Bessou S, Felnerova D, Vaheri A, Taïeb A. The proteolytic potential of normal human melanocytes: comparison with other skin cells and melanoma cell lines. PIGMENT CELL RESEARCH 1996; 9:255-64. [PMID: 9014212 DOI: 10.1111/j.1600-0749.1996.tb00115.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
To understand the contribution of epidermal melanocytes in the proteolytic potential of human skin, we have studied melanocytes grown in a low-serum medium deprived of phorbol esters, cholera toxin, and other non-physiological supplements. We focused on the plasminogen activation system and certain matrix metalloproteinases (gelatinases). Supposing that the proteolytic activity of cells can influence binding to collagen matrix and its reorganization, we have analyzed these parameters as well. We found that human melanocytes secreted tissue-type plasminogen activator and utilised it to generate cell-bound plasmin. No urokinase-type plasminogen activator was detected in the cultures but its receptor was found in cell extracts. Both the 72 kDa and 92 kDa gelatinases were secreted by the cells and in equal amounts. In addition, melanocytes secreted the wide-spectrum proteinase inhibitor alpha-2-macroglobulin. Melanocytes cast into collagen matrices retained a rounded morphology, did not extend processes, and were unable to contract collagen lattices. As a control, these parameters were investigated in parallel in cultures of human keratinocytes, dermal fibroblasts, and two melanoma cell lines. The obtained characteristics suggest that normal human melanocytes are proteolytically active cells. This function may pertain to skin physiology and pathophysiology.
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Affiliation(s)
- J Bizik
- Laboratoire de Dermatologie, Hôpital Pellegrin-Enfants, Université Victor Ségalen Bordeaux II, France
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21
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Wijnberg M, Nieuwenbroek N, Slomp J, Quax P, Verheijen J. Urokinase and tissue-type plasminogen activator stimulate human vascular smooth muscle cell migration. ACTA ACUST UNITED AC 1996. [DOI: 10.1016/s0268-9499(96)80055-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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22
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BECHTEL MJ, SCHAEFER BM, KRAMER MD. Plasminogen activator inhibitor type-2 in the lesional epidermis of lupus erythematosus. Br J Dermatol 1996. [DOI: 10.1111/j.1365-2133.1996.tb16223.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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Buessecker F, Reinartz J, Kramer MD. tPA of human keratinocytes: contribution to cell surface-associated plasminogen activation and upregulation by retinoic acid. Exp Dermatol 1995; 4:357-64. [PMID: 8608343 DOI: 10.1111/j.1600-0625.1995.tb00060.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We tested distinct variants of a human keratinocyte line (HaCaT) for the expression of tissue-type plasminogen activator (tPA)-specific mRNA, as well as cell surface-associated and secreted tPA. Cells of early passages (passage no. 22) only expressed urokinase plasminogen activator (uPA)- but not tPA-specific mRNA. Cells after prolonged culture (passage no. 44) expressed uPA- and tPA-specific mRNA, but did not release tPA in the extracellular space and did not display surface-associated tPA. HaCaT cells transformed with the c-Ha-ras oncogene (HaCaTras) showed both secreted and surface-associated tPA antigen. The secreted and the surface-associated plasminogen activator (PA)-activity of HaCaTras cells were in part inhibitable by anticatalytic anti-tPA antibodies, thus indicating that tPA contributes to extracellular and surface-associated plasminogen activation. Finally, we demonstrate that tPA secretion of HaCaT 44 cells can be induced by retinoic acid, most likely via interaction of retinoic acid with nuclear-associated retinoic acid-receptor(s).
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Affiliation(s)
- F Buessecker
- Institut für Immunologie der Universität Laboratorium für Immunpathologie, Heidelberg, Germany
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Conese M, Blasi F. The urokinase/urokinase-receptor system and cancer invasion. BAILLIERE'S CLINICAL HAEMATOLOGY 1995; 8:365-89. [PMID: 7549068 DOI: 10.1016/s0950-3536(05)80273-2] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
u-PA binds with high affinity to its specific GPI-anchored receptor on the cell surface. The binding has at least two important consequences: (1) it enhances the rate of plasminogen activation on the cell surface; and (2) it focuses the u-PA proteolytic activity at the leading front of migrating cells. Several recent findings suggest that surface-bound u-PA is essential for the invasive ability of tumour cells, even if a picture is emerging indicating a concerted action with other proteases, like collagenases and cathepsin B (Kobayashi et al, 1992; Ossowski, 1992; Schmitt et al, 1992; (Danø et al, 1994). In some tumours, e.g. colon, breast and skin cancer, in situ hybridization studies have given an insight into the u-PA/u-PAR tumour biology showing a complex interplay between stromal and cancer cells Danø et al, 1994). u-PA, u-PAR, and PAI-1 tumour content are now well established prognostic factor in breast cancer. This body of knowledge could be used for theurapeutic purposes. For example, a large study with 671 patients has allowed the identification of node-negative patients which, according to their u-PA levels, would need adjuvant therapy (Foekens et al, 1992). Many other tumours, especially colorectal cancer, expect a direct clinical evaluation of u-PA, u-PAR and serpins as prognostic factors.
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Affiliation(s)
- M Conese
- Dipartimento di Scienze Biomedicine e Oncologia Umana, Sezione di Patologia Generale Policlinico, Bari, Italy
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25
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Boxman IL, Quax PH, Löwik CW, Papapoulos SE, Verheijen J, Ponec M. Differential regulation of plasminogen activation in normal keratinocytes and SCC-4 cells by fibroblasts. J Invest Dermatol 1995; 104:374-8. [PMID: 7861005 DOI: 10.1111/1523-1747.ep12665844] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The plasminogen activator (PA)/plasmin system is thought to be involved in processes such as tumor invasion and wound healing, during which epithelial and mesenchymal cells come close together. However, information on regulation of the PA/plasmin system during epithelial-mesenchymal interactions is scarce. Therefore, we examined the in vitro modulation of the production and activity of the components of the PA/plasmin system in squamous carcinoma cells (SCC-4) and normal human keratinocytes in relation to cell density and the presence or absence of fibroblasts (3T3 cells). There was an inverse relation between cell density and mRNA expression for urokinase-type plasminogen activator (u-PA) and u-PA receptor in both SCC-4 cells and keratinocytes. In addition, such a relation was found for plasminogen activator inhibitor types 1 (PAI-1) and 2 (PAI-2) in SCC-4 monocultures, but not in keratinocyte monocultures. In contrast to monocultures, variation of cell density did not affect the mRNA expression of the components of the PA/plasmin system in cocultures of SCC-4 cells or keratinocytes with 3T3 cells. However, the relative expression of mRNAs in co-cultures was clearly different from that in monocultures, especially at low cell density. For most of the components of the PA/plasmin system, a decrease in mRNA expression and u-PA receptor protein was observed at most cell densities, whereas for PAI-1 only in keratinocytes a marked increase was documented. Zymography of supernatants revealed that the levels of both free u-PA and PA-PAI were increased in SCC-4/3T3 co-cultures, whereas in keratinocytes/3T3 co-cultures, only levels of the PA-PAI complex were increased, while the amount of free u-PA activity decreased. This occurred despite the increase u-PA immunoreactivity and was probably caused by the markedly elevated levels of immunoreactive PAI-1. The results of the present study reveal that the production and synthesis of various components of the PA/plasmin system in keratinocytes and SCC-4 cells depend on the density of epithelial cells and are modulated by fibroblasts, probably through a direct cell-cell or cell-matrix contact. Fibroblast-induced modulations are similar in keratinocytes and SCC-4 cells except for the regulation of PAI-1, which is markedly enhanced only in keratinocytes. This suggests that the modulation of PA activity in the direct microenvironment may be different under physiologic and pathologic conditions.
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Affiliation(s)
- I L Boxman
- Department of Dermatology, University Hospital Leiden, The Netherlands
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