1
|
Urokinase plasminogen activator as an anti-metastasis target: inhibitor design principles, recent amiloride derivatives, and issues with human/mouse species selectivity. Biophys Rev 2022; 14:277-301. [PMID: 35340592 PMCID: PMC8921380 DOI: 10.1007/s12551-021-00921-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Accepted: 11/18/2021] [Indexed: 01/09/2023] Open
Abstract
The urokinase plasminogen activator (uPA) is a widely studied anticancer drug target with multiple classes of inhibitors reported to date. Many of these inhibitors contain amidine or guanidine groups, while others lacking these groups show improved oral bioavailability. Most of the X-ray co-crystal structures of small molecule uPA inhibitors show a key salt bridge with the side chain carboxylate of Asp189 in the S1 pocket of uPA. This review summarises the different classes of uPA inhibitors, their binding interactions and experimentally measured inhibitory potencies and highlights species selectivity issues with attention to recently described 6-substituted amiloride and 5‑N,N-(hexamethylene)amiloride (HMA) derivatives.
Collapse
|
2
|
Demers-Mathieu V, Underwood MA, Dallas DC. Premature delivery impacts the concentration of plasminogen activators and a plasminogen activator inhibitor and the plasmin activity in human milk. Front Pediatr 2022; 10:917179. [PMID: 36016873 PMCID: PMC9396237 DOI: 10.3389/fped.2022.917179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2022] [Accepted: 07/20/2022] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND AND AIMS Plasmin in human milk partially hydrolyzes milk proteins within the mammary gland and may enhance the hydrolysis of milk proteins within the infant's stomach. This study examined the effects of extremely preterm (EP)-, very preterm (VP)-, and term-delivery on plasmin activity and the concentrations of plasminogen activators [urokinase-type plasminogen activator (uPA) and tissue-type plasminogen activator (tPA)], plasminogen activator inhibitor type 1 (PAI-1) and the complexes of PAI-1/uPA and PAI-1/tPA in human milk. MATERIALS AND METHODS Human milk samples were collected from mothers who delivered extremely preterm infants [24-27 weeks gestational age (GA), n = 20], very preterm infants (28-32 weeks GA, n = 12), and term infants (38-39 weeks GA, n = 8) during 2-72 days postnatally. Plasmin activity was determined using fluorometric substrate assay, whereas concentrations of uPA, tPA, PAI-1, the PAI-1/uPA complex and the PAI-1/tPA complex were quantified by ELISA. RESULTS Plasmin activity, uPA and tPA were detected in all human milk samples, PAI-1 and the PAI-1/uPA complex were present in 42.5 and 32.5% of milk samples, respectively, and the PAI-1/tPA complex was not detected. Plasmin activity was correlated negatively with postnatal age and postmenstrual age (PMA) in the VP group and positively with postnatal age in the term group. uPA and tPA concentrations decreased with increasing postnatal age in both EP and VP groups but did not correlate in the term group. uPA concentration was correlated positively with GA in the VP group and tended to be elevated with increasing GA in the combined three groups. In contrast, tPA concentrations were correlated negatively with GA and PMA in the combined three groups (P < 0.008) and with PMA in the EP and VP groups. PAI-1 concentration tended to be correlated positively with postnatal age in the combined three groups. No correlation was detected with the PAI-1/uPA complex. CONCLUSION Premature delivery impacted the plasmin activity and the concentrations of uPA, tPA, and PAI-1 in human milk. Whether these changes in milk plasminogen activators and inhibitors have a role in balancing the proteolytic digestion of premature infants remains to be investigated.
Collapse
Affiliation(s)
- Veronique Demers-Mathieu
- Nutrition Program, School of Biological and Population Health Sciences, College of Public Health and Human Sciences, Oregon State University, Corvallis, OR, United States
| | - Mark A Underwood
- Department of Pediatrics, University of California, Davis, Sacramento, CA, United States
| | - David C Dallas
- Nutrition Program, School of Biological and Population Health Sciences, College of Public Health and Human Sciences, Oregon State University, Corvallis, OR, United States
| |
Collapse
|
3
|
Stepanova V, Jayaraman PS, Zaitsev SV, Lebedeva T, Bdeir K, Kershaw R, Holman KR, Parfyonova YV, Semina EV, Beloglazova IB, Tkachuk VA, Cines DB. Urokinase-type Plasminogen Activator (uPA) Promotes Angiogenesis by Attenuating Proline-rich Homeodomain Protein (PRH) Transcription Factor Activity and De-repressing Vascular Endothelial Growth Factor (VEGF) Receptor Expression. J Biol Chem 2016; 291:15029-45. [PMID: 27151212 DOI: 10.1074/jbc.m115.678490] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Indexed: 01/09/2023] Open
Abstract
Urokinase-type plasminogen activator (uPA) regulates angiogenesis and vascular permeability through proteolytic degradation of extracellular matrix and intracellular signaling initiated upon its binding to uPAR/CD87 and other cell surface receptors. Here, we describe an additional mechanism by which uPA regulates angiogenesis. Ex vivo VEGF-induced vascular sprouting from Matrigel-embedded aortic rings isolated from uPA knock-out (uPA(-/-)) mice was impaired compared with vessels emanating from wild-type mice. Endothelial cells isolated from uPA(-/-) mice show less proliferation and migration in response to VEGF than their wild type counterparts or uPA(-/-) endothelial cells in which expression of wild type uPA had been restored. We reported previously that uPA is transported from cell surface receptors to nuclei through a mechanism that requires its kringle domain. Intranuclear uPA modulates gene transcription by binding to a subset of transcription factors. Here we report that wild type single-chain uPA, but not uPA variants incapable of nuclear transport, increases the expression of cell surface VEGF receptor 1 (VEGFR1) and VEGF receptor 2 (VEGFR2) by translocating to the nuclei of ECs. Intranuclear single-chain uPA binds directly to and interferes with the function of the transcription factor hematopoietically expressed homeodomain protein or proline-rich homeodomain protein (HHEX/PRH), which thereby lose their physiologic capacity to repress the activity of vehgr1 and vegfr2 gene promoters. These studies identify uPA-dependent de-repression of vegfr1 and vegfr2 gene transcription through binding to HHEX/PRH as a novel mechanism by which uPA mediates the pro-angiogenic effects of VEGF and identifies a potential new target for control of pathologic angiogenesis.
Collapse
Affiliation(s)
| | - Padma-Sheela Jayaraman
- School of Immunity and Infection, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B152TT, United Kingdom
| | - Sergei V Zaitsev
- Pharmacology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | | | - Khalil Bdeir
- From the Departments of Pathology and Laboratory Medicine and
| | - Rachael Kershaw
- School of Immunity and Infection, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B152TT, United Kingdom
| | - Kelci R Holman
- College of Arts and Sciences, Drexel University, Philadelphia, Pennsylvania 19104
| | - Yelena V Parfyonova
- Russian Cardiology Research Center, Moscow 121552, Russia, School (Faculty) of Fundamental Medicine, Lomonosov Moscow State University, Moscow, 117192, Russia, and
| | - Ekaterina V Semina
- Russian Cardiology Research Center, Moscow 121552, Russia, School (Faculty) of Fundamental Medicine, Lomonosov Moscow State University, Moscow, 117192, Russia, and
| | | | - Vsevolod A Tkachuk
- Russian Cardiology Research Center, Moscow 121552, Russia, School (Faculty) of Fundamental Medicine, Lomonosov Moscow State University, Moscow, 117192, Russia, and
| | - Douglas B Cines
- From the Departments of Pathology and Laboratory Medicine and
| |
Collapse
|
4
|
Ahmad A, Saha P, Evans C, Thurison T, Hoyer-Hansen G, Patel A, Modarai B, Smith A. The soluble urokinase plasminogen activator receptor and its fragments in venous ulcers. J Vasc Surg Venous Lymphat Disord 2014; 3:190-7. [PMID: 26993839 DOI: 10.1016/j.jvsv.2014.08.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Accepted: 08/08/2014] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Activation of proteolytic mechanisms at the cell surface through the activity of urokinase-type plasminogen activator (uPA) bound to its receptor, uPAR, is an important process in wound healing. The soluble forms of uPAR (suPAR and its fragments I, II, and III) have nonproteolytic functions that include chemotaxis, adhesion, and proliferation, which also have a role in wound healing. The aim of this study was to determine whether suPAR and its cleaved fragments are present in venous ulcers and whether their levels are associated with healing. METHODS Ulcer exudates were collected from patients with venous leg ulcers (n = 30). Healing was defined as complete re-epithelialization within 6 months of compression therapy. Time-resolved fluorescence immunoassays were validated for quantification of suPAR and its fragments in ulcer exudates. The effect of exudates on keratinocyte migration was analyzed by an in vitro scratch assay. RESULTS Ulcer exudates from patients who healed (n = 9) had approximately threefold higher levels of intact suPAR (P = .005), twofold higher levels of suPARI (P = .03), and approximately threefold higher levels suPARII-III (P < .0001) compared with nonhealers (n = 21). Exudate from healing ulcers stimulated keratinocyte migration (P = .02), whereas depletion of suPAR from exudates resulted in cell apoptosis. CONCLUSIONS We conclude that suPAR and its fragments are present in the environs of venous ulcers and may act as indicators of the propensity of venous ulcers to heal, with suPARII-III being the best discriminator. We speculate that suPAR and its fragments may have a role in the maintenance of an optimal ulcer-healing environment.
Collapse
Affiliation(s)
- Anwar Ahmad
- King's College London, BHF Centre of Research Excellence and NIHR Biomedical Research Centre at GSTT and King's College London, Academic Department of Vascular Surgery, Cardiovascular Division, St Thomas' Hospital, London, United Kingdom
| | - Prakash Saha
- King's College London, BHF Centre of Research Excellence and NIHR Biomedical Research Centre at GSTT and King's College London, Academic Department of Vascular Surgery, Cardiovascular Division, St Thomas' Hospital, London, United Kingdom
| | - Colin Evans
- King's College London, BHF Centre of Research Excellence and NIHR Biomedical Research Centre at GSTT and King's College London, Academic Department of Vascular Surgery, Cardiovascular Division, St Thomas' Hospital, London, United Kingdom
| | - Tine Thurison
- Finsen Laboratory, Copenhagen University Hospital, Copenhagen, Denmark
| | | | - Ashish Patel
- King's College London, BHF Centre of Research Excellence and NIHR Biomedical Research Centre at GSTT and King's College London, Academic Department of Vascular Surgery, Cardiovascular Division, St Thomas' Hospital, London, United Kingdom
| | - Bijan Modarai
- King's College London, BHF Centre of Research Excellence and NIHR Biomedical Research Centre at GSTT and King's College London, Academic Department of Vascular Surgery, Cardiovascular Division, St Thomas' Hospital, London, United Kingdom
| | - Alberto Smith
- King's College London, BHF Centre of Research Excellence and NIHR Biomedical Research Centre at GSTT and King's College London, Academic Department of Vascular Surgery, Cardiovascular Division, St Thomas' Hospital, London, United Kingdom.
| |
Collapse
|
5
|
Hildenbrand R, Allgayer H, Marx A, Stroebel P. Modulators of the urokinase-type plasminogen activation system for cancer. Expert Opin Investig Drugs 2010; 19:641-52. [PMID: 20402599 DOI: 10.1517/13543781003767400] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
IMPORTANCE OF THE FIELD The serine protease urokinase-type plasminogen activator (uPA) and its receptor uPAR as well as two specific inhibitors, the plasminogen activator inhibitor type-1 (PAI-1) and type-2 (PAI-2), are involved in the control of extracellular matrix turnover and tumor growth. Data accumulating over the past 20 years have made increasingly clear that the uPA system has a multifunctional role in neoplastic evolution, affecting cancer cell proliferation, tumor angiogenesis, adhesion and migration. AREAS COVERED IN THIS REVIEW Several therapeutic strategies inhibiting the uPA system have been or are currently being developed for suppression of tumor growth. This review examines the role of the uPA system in tumor progression and assesses the various therapeutic strategies developed to selectively exploit this system. WHAT WILL THE READER GAIN We focus on the therapeutic developments of the last 15 years. In addition to antibodies and recombinant uPA- or uPAR-derived proteins, various antagonistic peptides as well as small molecules have been designed and synthesized that inhibit the uPA system, leading to reduced tumor progression. TAKE HOME MESSAGE The multifunctional potential of the uPA system in cancer has rendered this system an attractive novel target for anticancer therapy. A few novel tumor biology-based therapeutic strategies reported here, opening new ways for patient-optimized and individualized cancer therapy. It may be the right time to evaluate the hypothesis that the uPA system plays a pivotal role in cancer progression and that targeting this system will lead to clinical benefit in cancer patients.
Collapse
|
6
|
Buttle DJ, Bramwell H, Hollander AP. Proteolytic mechanisms of cartilage breakdown: a target for arthritis therapy? Mol Pathol 2010; 48:M167-77. [PMID: 16696000 PMCID: PMC407956 DOI: 10.1136/mp.48.4.m167] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- D J Buttle
- Institute for Bone & Joint Medicine, Department of Human Metabolism & Clinical Biochemistry, University of Sheffield Medical School, Beech Hill Road, Sheffield S10 2RX
| | | | | |
Collapse
|
7
|
Allgayer H. Pdcd4, a colon cancer prognostic that is regulated by a microRNA. Crit Rev Oncol Hematol 2009; 73:185-91. [PMID: 19836969 DOI: 10.1016/j.critrevonc.2009.09.001] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2008] [Revised: 08/03/2009] [Accepted: 09/09/2009] [Indexed: 01/02/2023] Open
Abstract
The novel tumor suppressor Pdcd4 inhibits neoplastic transformation, tumor progression and translation. Furthermore, we and others have recently shown that Pdcd4 suppresses invasion and intravasation, at least in part by suppressing expression of the invasion-related urokinase receptor (u-PAR) gene via the transcription factors Sp1/Sp3. Nevertheless, relatively little is known about mechanisms that regulate Pdcd4 expression in cancer. MicroRNAs (miRNAs) have been recently discovered and shown to be naturally occurring non-coding RNAs that control gene expression via specific sites within the 3'UTR of target miRNAs. This short review will focus on our recent finding that the microRNA miR-21 posttranscriptionally regulates Pdcd4, as well as invasion, intravasation, and metastasis. Furthermore, we will review the first translational and clinical results concerning the prognostic value of Pdcd4, in particular our own data that show Pdcd4 to be a novel and independent prognostic factor in colorectal cancer, and a potential supportive diagnostic tool for discriminating normal colonic tissues from benign adenomas and colorectal carcinomas.
Collapse
Affiliation(s)
- Heike Allgayer
- Dept. Experimental Surgery/Molecular Oncology of Solid Tumors (Collaboration Unit German Cancer Research Center-DKFZ-Heidelberg), Medical Faculty Mannheim, Ruprecht-Karls-University Heidelberg, Theodor-Kutzer-Ufer 1-3, 68167 Mannheim, Germany.
| |
Collapse
|
8
|
Allgayer H, Aguirre-Ghiso JA. The urokinase receptor (u-PAR)--a link between tumor cell dormancy and minimal residual disease in bone marrow? APMIS 2008; 116:602-14. [PMID: 18834405 DOI: 10.1111/j.1600-0463.2008.00997.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Minimal residual disease (MRD) is hypothesized to be the major cause of tumor recurrence and metastasis even years and decades after primary cancer diagnosis and curative solid tumor resection. In these patients disseminated tumor cells reflecting MRD can be detected in the bone marrow years after treatment. It is to be assumed that genetic determinants and a complex interplay between the disseminated tumor cells and their microenvironment in the bone marrow are responsible for tumor cell dormancy and the final reactivation towards metastasis. The urokinase receptor (u-PAR), a critical regulator of invasion, intravasation, and metastasis, is found to be a key player in regulating the shift between single cell tumor dormancy and proliferation. This has mainly been attributed to a regulation by u-PAR of integrins, and the ability of the latter to propagate signals from fibronectin through the EGF-receptor, ERK, and p38 signaling. Interestingly, u-PAR is found in disseminated tumor cells in the bone marrow of solid cancer patients, and is associated with the expansion of these cells and clinical prognosis. Here we summarize and discuss findings on disseminated tumor cells in the bone marrow, MRD and the role of u-PAR in tumor biology, especially focusing on its specific role in providing a switch between tumor cell proliferation and dormancy. Finally, we discuss the hypothesis that u-PAR might be an essential molecule in bone marrow disseminated tumor cells for long-term survival during dormancy, and/or reactivation of their proliferation years after primary treatment.
Collapse
Affiliation(s)
- Heike Allgayer
- Department of Experimental Surgery and Molecular Oncology of Solid Tumors, Medical Faculty Mannheim, University of Heidelberg, and DKFZ German Cancer Research Center Heidelberg, Germany.
| | | |
Collapse
|
9
|
Cavallaro U, del Vecchio A, Massazza G, Tazzari PL, Soria MR. Targeting of Cytotoxic Conjugates to Kaposi's Sarcoma-Derived Cells. Drug Deliv 2008. [DOI: 10.3109/10717549309022765] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
|
10
|
Allgayer H. Molecular regulation of an invasion-related molecule – options for tumour staging and clinical strategies. Eur J Cancer 2006; 42:811-9. [PMID: 16617013 DOI: 10.1016/j.ejca.2006.01.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2006] [Accepted: 01/19/2006] [Indexed: 11/18/2022]
Abstract
This review provides a summary of the European Association for Cancer Research Award Lecture, presented at the ECCO13 meeting in Paris in November 2005. It is a brief overview on the biological and clinical relevance of the urokinase receptor (u-PAR), an essential molecule to promote invasive and metastatic tumour phenotype and shown to be associated with early relapse and poor prognosis in many different types of cancers. The review summarizes the most important transcriptional mechanisms regulating u-PAR gene, and will focus on the differential binding of transcription factors to u-PAR promoter elements from studies in resected tumour and normal tissues of colorectal and gastric cancer patients. These studies conducted by our group may help to understand transcriptional mechanisms, which are employed to promote invasion and metastasis, in subpopulations of cancer patients. Such studies could lead to a more target-oriented patient selection and therapy against transcriptional and oncogeneic regulators in cancer.
Collapse
Affiliation(s)
- Heike Allgayer
- Department of Experimental Surgery and Molecular Oncology, Klinikum Mannheim, Ruprecht Karls University Heidelberg, Theodor Kutzer Ufer 1-3, 68135 Mannheim, Germany.
| |
Collapse
|
11
|
Magill C, Katz BA, Mackman RL. Emerging therapeutic targets in oncology: urokinase-type plasminogen activator system. ACTA ACUST UNITED AC 2005. [DOI: 10.1517/14728222.3.1.109] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
|
12
|
Kwaan HC, Wang J, Weiss I. Expression of receptors for plasminogen activators on endothelial cell surface depends on their origin. J Thromb Haemost 2004; 2:306-12. [PMID: 14995994 DOI: 10.1111/j.1538-7933.2004.00593.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Receptors for plasminogen activators present on endothelial cell (EC) surface regulate local plasmin activity. Plasmin generation by human ECs, derived from cerebral cortex, skin and lung, iliac artery, iliac vein, aorta and coronary artery, was studied. The respective ECs were treated with recombinant tissue plasminogen activator (rt-PA) or with recombinant urokinase-type plasminogen activator (ru-PA), washed, plasminogen added and the plasmin generated then assayed. The largest amounts of plasmin were generated by cerebral ECs, under baseline conditions or after exposure to rt-PA or ru-PA (P < 0.0001). Exposure to rt-PA also resulted in more plasmin generation than ru-PA in the cerebral ECs (P < 0.0001) but not in the other ECs. Heparin enhanced plasmin generation by both rt-PA and ru-PA. Specific antibody against annexin II, a t-PA receptor, blocked plasmin generation by rt-PA. Western blotting showed higher amounts of annexin II on the cell membrane in cerebral ECs. This suggests that expression of annexin II in ECs depends on their location, being greatest in cerebral ECs. In contrast, expression of u-PA receptor was the same for all ECs. This has implications for higher risk of intracranial bleeding during thrombolytic therapy, and for a role of t-PA in neurological development and function.
Collapse
Affiliation(s)
- H C Kwaan
- Division of Hematology and Oncology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA.
| | | | | |
Collapse
|
13
|
Allgayer H. Molecular regulation of urokinase-receptor gene expression as one potential concept for molecular staging and therapy. Recent Results Cancer Res 2003; 162:15-30. [PMID: 12790318 DOI: 10.1007/978-3-642-59349-9_2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
The urokinase-receptor (u-PAR) is a central molecule of invasion and metastasis promoting plasminogen-dependent extracellular matrix degradation in diverse carcinoma types such as gastric or colon cancer. Overexpression of u-PAR has been reported to occur mainly at the transcriptional level in malignant cells, and has been shown to indicate a poor clinical prognosis of cancer patients. This review will give an overview on experimental findings on u-PAR and its function, molecular mechanisms of its regulation, and its impact for future clinical decision planning and potential therapeutic concepts.
Collapse
Affiliation(s)
- Heike Allgayer
- Department of Surgery, Klinikum Grosshadern, Ludwig Maximilians University of Munich, Marchioninistr. 15, 81377 Munich, Germany
| |
Collapse
|
14
|
Römisch J, Feussner A, Stöhr HA. Quantitation of the factor VII- and single-chain plasminogen activator-activating protease in plasmas of healthy subjects. Blood Coagul Fibrinolysis 2001; 12:375-83. [PMID: 11505081 DOI: 10.1097/00001721-200107000-00007] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Plasma samples of 189 healthy subjects were investigated for antigen levels of the recently reported factor VII- and single-chain plasminogen activator-activating protease (FSAP) and the corresponding pro-urokinase activating potencies. While the age of donors had no significant effect on the investigated parameters, female plasmas revealed a trend to higher antigen contents and activity levels. Surprisingly, as much as 9% of all samples contained significantly reduced single-chain urinary plasminogen activator activating potential, whereas antigen concentrations were normal. Additionally, 1% of the plasmas was found to decrease in both FSAP antigen and activity contents. FSAP of three subjects displaying reduced activities throughout a follow-up period of 6 months were purified from plasmas and were characterized. As compared with pool plasma derived FSAP, investigation of the individual preparations confirmed their reduced potency to activate pro-urokinase. However, factor VII activation was not affected. It is speculated that the FSAP binding site for single-chain plasminogen activators is affected, potentially by as yet unknown polymorphism(s) or mutation(s).
Collapse
Affiliation(s)
- J Römisch
- Aventis Behring GmbH, Research, Marburg, Germany.
| | | | | |
Collapse
|
15
|
Rajagopal V, Kreitman RJ. Recombinant toxins that bind to the urokinase receptor are cytotoxic without requiring binding to the alpha(2)-macroglobulin receptor. J Biol Chem 2000; 275:7566-73. [PMID: 10713063 DOI: 10.1074/jbc.275.11.7566] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The alpha(2-)macroglobulin receptor (alpha(2)MR) has been reported to mediate the internalization of the urokinase plasminogen activator receptor (uPAR) via ligand binding to both receptors. To target malignant uPAR-expressing cells and to determine whether uPAR can internalize without ligand binding to alpha(2)MR, we engineered two recombinant toxins, ATF-PE38 and ATF-PE38KDEL. Each consists of the amino-terminal fragment (ATF) of human urokinase and a truncated form of Pseudomonas exotoxin (PE) devoid of domain Ia, which binds alpha(2)MR. ATF-PE38 and ATF-PE38KDEL were cytotoxic toward malignant uPAR-bearing cells, with IC(50) values as low as 0.02 ng/ml (0.3 pM). Cytotoxicity could be blocked using either recombinant urokinase or free ATF, indicating that the cytotoxicity of the recombinant toxins was specific. Radiolabeled ATF-PE38 had high affinity for uPAR (K(d) = 0.4-8 nM) on a variety of different malignant cell types and internalized at a rate similar to that of ATF. The cytotoxicity was not diminished by receptor-associated protein, which binds and shields the alpha(2)MR from other proteins, or by incubation with phorbol myristate acetate, which is known to decrease the number of alpha(2)MRs in U937 cells or by antibodies to alpha(2)MR. Therefore, these recombinant toxins appear to internalize via uPAR without association with the alpha(2)MR.
Collapse
Affiliation(s)
- V Rajagopal
- Laboratory of Molecular Biology, Division of Basic Sciences, NCI, National Institutes of Health, Bethesda, Maryland 20892, USA
| | | |
Collapse
|
16
|
Herszényi L, Plebani M, Carraro P, De Paoli M, Roveroni G, Cardin R, Foschia F, Tulassay Z, Naccarato R, Farinati F. Proteases in gastrointestinal neoplastic diseases. Clin Chim Acta 2000; 291:171-87. [PMID: 10675722 DOI: 10.1016/s0009-8981(99)00227-2] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Cysteine and serine proteases are involved in cancer invasion and metastasis. In the past few years we investigated the tissue levels of these proteases in gastric cancer (GC), gastric precancerous changes (CAG), colorectal cancer (CRC) and the plasma and serum levels of proteases in several gastrointestinal tumours, using ELISA methods. Significantly higher antigen levels were found not only in GC tissue but also in CAG with respect to the levels found normal tissue; with respect to CAG, patients with dysplasia had higher levels than patients without dysplasia. The same findings were obtained in CRC. In general protease levels correlated with the major histomorphological parameters, such as grading and histotype in GC as well as in CRC. Tissue protease levels had a strong prognostic impact in GC, in which UPA was singled out by multivariate analysis as the major prognostic factor, and CRC. The plasma levels of urokinase-type plasminogen activator (UPA) and the serum levels of cathepsin B were significantly increased in patients with gastrointestinal tumours. In conclusions, cysteine and serine proteases may have a part not only in GC and CRC invasion and metastasis, but also in the progression of gastric precancerous changes into cancer. They are strong prognostic factors in GC and CRC. These proteases may also have a role as tumour markers in the early diagnosis of gastrointestinal tract tumours.
Collapse
Affiliation(s)
- L Herszényi
- Second Department of Medicine, Semmelweis University Medical School, Budapest, Hungary
| | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Ellis V, Whawell SA, Werner F, Deadman JJ. Assembly of urokinase receptor-mediated plasminogen activation complexes involves direct, non-active-site interactions between urokinase and plasminogen. Biochemistry 1999; 38:651-9. [PMID: 9888805 DOI: 10.1021/bi981714d] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The binding of the zymogenic form of urokinase-type plasminogen activator (pro-uPA) to its specific cellular receptor, uPAR, leads to a large potentiation of plasmin generation. This is dependent on the concurrent cellular binding of plasminogen, and is completely abrogated by the plasminogen lysine-binding site ligand, 6-aminohexanoic acid. Previous data have provided circumstantial evidence for the formation of specific complexes to mediate the kinetically favorable reciprocal interactions between the protease and zymogen components [Ellis, V., and Dano, K. (1993) J. Biol. Chem. 268, 4806-4813]. To further investigate the formation of these putative complexes, we have studied the effect of various lysine-binding site ligands on the binding and activation of plasminogen on U937 cells. Lysine-binding site ligands resembling internal lysine residues, such as Nalpha-acetyl-L-lysine methyl ester, were found to specifically inhibit uPAR-mediated cell-surface plasminogen activation at concentrations up to 40-fold lower than those inhibiting the cellular binding of 125I-labeled plasminogen (IC50s 300 microM vs 8.5 mM). By contrast, 6-aminohexanoic acid, resembling a C-terminal lysine residue, did not display this disparity (IC50s 25 vs 30 microM). These lysine analogues were also found to compete a non-active-site interaction between uPA and plasminogen, detected by surface plasmon resonance (Kd 50 nM), at concentrations correlating with their effect on cell-surface plasminogen activation, suggesting that this interaction is part of the kinetic mechanism. Consistent with this, synthetic peptides corresponding to the sequence uPA149-158 (GQKTLRPRFK) and uPA149-157 (GQKTLRPRF) specifically abolished the amplification of cell-surface plasminogen activation. These data demonstrate that a novel non-active-site interaction between uPA and plasminogen is necessary for the assembly and efficiency of cell-surface plasminogen activation complexes.
Collapse
Affiliation(s)
- V Ellis
- Thrombosis Research Institute, London, United Kingdom.
| | | | | | | |
Collapse
|
18
|
Wechselwirkungen zwischen Fibrinolysesystem und der Endothelzelle: die Modulation des fibrinolytischen Potentials. Hamostaseologie 1999. [DOI: 10.1007/978-3-662-07673-6_61] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
|
19
|
Wilkins-Port CE, McKeown-Longo PJ. Degradation of distinct forms of multimeric vitronectin by human fibroblasts. BIOCHIMICA ET BIOPHYSICA ACTA 1998; 1404:353-66. [PMID: 9739164 DOI: 10.1016/s0167-4889(98)00076-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The plasma protein vitronectin is thought to be an important regulator of extravascular plasminogen activation. In previous studies we have shown that a disulfide stabilized multimeric form of vitronectin is endocytosed and degraded by fibroblast cells (T.S. Panetti, P.J. McKeown-Longo, J. Biol. Chem. 268 (1993) 11988-11993; P.J. McKeown-Longo, T.S. Panetti, in: K.T. Preissner, S. Rosenblatt, C. Kost, J. Wegerhoff, D.F. Mosher (Eds.), Biology of Vitronectins and their Receptors, Elsevier Science Publishers, Amsterdam, 1993, pp. 111-118). The preparation of multimeric vitronectin used in these earlier studies was in the form of high molecular weight disulfide-bonded aggregates which were stable in sodium dodecyl sulfate (SDS). To address the question of whether vitronectin needed to be in the form of disulfide stabilized multimers in order to be endocytosed, a multimeric vitronectin, which was not disulfide stabilized, was prepared from vitronectin that had been treated with reducing agent and alkylated with iodoacetamide. The resulting protein migrated as a 65/75 kDa protein on SDS gels in the absence of reducing agent, confirming that this form of vitronectin was no longer stabilized into disulfide-bonded aggregates. However, the protein was still multimeric when analyzed by native gels and could be converted to SDS stable multimers by cross-linking agents. This result demonstrated that reduced and alkylated vitronectin aggregates into multimeric forms which are not stable in SDS. Similar to disulfide stabilized multimers, alkylated multimers of vitronectin bound to sulfated proteoglycans in the extracellular matrix and were endocytosed and degraded. Degradation of both forms of vitronectin was inhibited with arginine-glycine-aspartic acid peptides, an anti-alphavbeta5 antibody and heparin. Chloroquine and wortmannin were also able to inhibit degradation of both forms of vitronectin, indicating that both multimeric forms were following the same endocytic and degradative pathway. These results suggest that the organization of vitronectin into a multimeric form which will be recognized for endocytosis does not require disulfide bond stabilization. This study further suggests that recognition of vitronectin for endocytosis is dependent upon its conversion from a monomeric to a multivalent form (C.E. Wilkins-Port, P.J. McKeown-Longo, Mol. Biol. Cell 8:S:64A (1997).
Collapse
Affiliation(s)
- C E Wilkins-Port
- Cell and Molecular Biology Program and the Department of Physiology and Cell Biology (Mail Code 134), Neil Hellman Medical Research Building, Albany Medical College of Union University, 47 New Scotland Avenue, Albany, NY 12208, USA
| | | |
Collapse
|
20
|
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.
Collapse
Affiliation(s)
- J M Bator
- Center for Molecular Biology of Oral Diseases, University of Illinois at Chicago, Illinois 60612, USA
| | | | | |
Collapse
|
21
|
|
22
|
Abstract
The function of any known gene is often found by DNA or protein homology scanning. Conversely, it is equally rewarding to search for the genetic basis behind a known function. Here, Ghislain Opdenakker and colleagues examine the known and possible novel genes and molecular events underlying the phenomenon of leukocytosis, one of the most common clinical manifestations of inflammatory problems.
Collapse
Affiliation(s)
- G Opdenakker
- Rega Institute for Medical Research, University of Leuven, Belgium
| | | | | |
Collapse
|
23
|
Vascular Smooth Muscle Cells Potentiate Plasmin Generation by Both Urokinase and Tissue Plasminogen Activator-Dependent Mechanisms: Evidence for a Specific Tissue-Type Plasminogen Activator Receptor on These Cells. Blood 1997. [DOI: 10.1182/blood.v90.6.2312.2312_2312_2322] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Plasminogen activators play a role in the response of the vessel wall to injury, presumably by mediating the degradation of extracellular matrix (ECM) by vascular smooth muscle cells (VSMCs) that is necessary for their migration and proliferation. We have therefore investigated the ability of VSMCs to assemble specific cell surface plasminogen-activating systems. Urokinase-type plasminogen activator (uPA) bound to a single class of site on VSMCs (kd, 2 nmol/L), binding of pro-uPA resulted in a large potentiation of plasmin generation and both were competed by antibodies to the uPA receptor (uPAR). Tissue-type plasminogen activator (tPA) also bound to VSMCs as determined by functional assay, with the binding isotherms showing two classes of binding site with apparent kds of 25 and 300 nmol/L. tPA binding to the higher affinity site caused a greater than 90-fold enhancement of the activation of cell bound plasminogen, whereas the lower affinity binding, mediated primarily by the ECM, had little effect on tPA activity. The high-affinity binding of tPA to VSMCs resulted in an eightfold greater potential for plasmin generation than the binding of uPA, with this difference increasing to 15-fold after thrombin stimulation of the cells due to a 1.8-fold increase in tPA binding. These data show a novel specific tPA receptor on VSMCs that may be important for the regulation of plasminogen activation in various vascular pathologies.
Collapse
|
24
|
Vascular Smooth Muscle Cells Potentiate Plasmin Generation by Both Urokinase and Tissue Plasminogen Activator-Dependent Mechanisms: Evidence for a Specific Tissue-Type Plasminogen Activator Receptor on These Cells. Blood 1997. [DOI: 10.1182/blood.v90.6.2312] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractPlasminogen activators play a role in the response of the vessel wall to injury, presumably by mediating the degradation of extracellular matrix (ECM) by vascular smooth muscle cells (VSMCs) that is necessary for their migration and proliferation. We have therefore investigated the ability of VSMCs to assemble specific cell surface plasminogen-activating systems. Urokinase-type plasminogen activator (uPA) bound to a single class of site on VSMCs (kd, 2 nmol/L), binding of pro-uPA resulted in a large potentiation of plasmin generation and both were competed by antibodies to the uPA receptor (uPAR). Tissue-type plasminogen activator (tPA) also bound to VSMCs as determined by functional assay, with the binding isotherms showing two classes of binding site with apparent kds of 25 and 300 nmol/L. tPA binding to the higher affinity site caused a greater than 90-fold enhancement of the activation of cell bound plasminogen, whereas the lower affinity binding, mediated primarily by the ECM, had little effect on tPA activity. The high-affinity binding of tPA to VSMCs resulted in an eightfold greater potential for plasmin generation than the binding of uPA, with this difference increasing to 15-fold after thrombin stimulation of the cells due to a 1.8-fold increase in tPA binding. These data show a novel specific tPA receptor on VSMCs that may be important for the regulation of plasminogen activation in various vascular pathologies.
Collapse
|
25
|
Köhler U, Hiller K, Martin R, Langanke D, Naumann G, Bilek K, Jänicke F, Schmitt M. Tumor-associated proteolytic factors uPA and PAI-1 in endometrial carcinoma. Gynecol Oncol 1997; 66:268-74. [PMID: 9264575 DOI: 10.1006/gyno.1997.4751] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The levels of plasminogen activator urokinase (uPA) and of its inhibitor (PAI-1) were measured by use of ELISA in the cytosol of tissue homogenates obtained from endometrial carcinomas and the marginal, tumor-free endometrium of postmenopausal patients (n = 64). Significantly higher median levels of uPA and PAI-1 were found in malignant endometrium (uPA 1.89 ng/mg, PAI-1 3.04 ng/mg) compared to tumor-free endometrium (uPA 0.84 ng/mg, PAI-1 1.01 ng/mg). Concerning uPA, no significant differences were found in dependence on histomorphological prognostic factors (staging, grading), but the median level of PAI-1 was significantly higher in G2/G3 carcinomas compared to G1 tumors (5.08 ng/mg vs 2.19 ng/mg). Because of the good prognosis of operated patients with endometrial carcinomas, the prognostic value of uPA and PAI-1 can only be decided by a larger number of patients and a long observation time.
Collapse
Affiliation(s)
- U Köhler
- Universitäts-Frauenklinik, Leipzig, Germany
| | | | | | | | | | | | | | | |
Collapse
|
26
|
Heegaard CW, Larsen LB, Rasmussen LK, Højberg KE, Petersen TE, Andreasen PA. Plasminogen activation system in human milk. J Pediatr Gastroenterol Nutr 1997; 25:159-66. [PMID: 9252902 DOI: 10.1097/00005176-199708000-00006] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Plasmin is the major endogenous protease present in milk. The level of plasmin activity is controlled by the availability of the precursor plasminogen and by the levels of plasminogen activators and inhibitors. Recently, a differential distribution of tissue-type plasminogen activator (t-PA) and urokinase-type plasminogen activator (u-PA) has been demonstrated in bovine milk. To assess whether this distribution pattern is a general feature, the occurrence of components of the plasminogen activation system in different fractions of human milk was investigated. METHODS Milk samples were separated into the following fractions; milk fat, skim milk, and milk cells by centrifugation. The different fractions were detected for the presence of plasminogen and plasminogen activators by immunoblotting and zymography. The distribution of t-PA and u-PA was investigated by ligand binding analysis. t-PA-catalyzed plasminogen activation was examined by a coupled chromogenic assay. RESULTS A differential distribution of plasminogen, t-PA, and u-PA was found. Casein micelles were found to exhibit t-PA and plasminogen binding activity, whereas the u-PA receptor was identified as the u-PA binding component in the cell fraction. Furthermore, human casein enhanced t-PA-catalyzed plasminogen activation, comparable to the enhancing effect obtained with fibrinogen fragments. CONCLUSION The finding of a differential distribution of u-PA and t-PA in milk suggests that the two activators may have different physiological functions, which involve protection against invading microorganisms and maintenance of patency and fluidity in the ducts of mammary gland, respectively.
Collapse
Affiliation(s)
- C W Heegaard
- Department of Molecular and Structural Biology, University of Aarhus, Denmark
| | | | | | | | | | | |
Collapse
|
27
|
Opdenakker G, Paemen L, Norga K, Masure S. Proteinase inhibition in invasive cancer therapy: four control levels of matrix degradation. Int J Cancer 1997; 70:628-30. [PMID: 9052766 DOI: 10.1002/(sici)1097-0215(19970304)70:5<628::aid-ijc22>3.0.co;2-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
|
28
|
Huang X, Xia W, Xiong C, Xiao D, Shen J, Zhou J. Studies on the relationship between urokinase plasminogen activator (uPA) and human sperm motility. Curr Med Sci 1997; 17:213-7. [PMID: 9812782 DOI: 10.1007/bf02895622] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/1997] [Indexed: 11/24/2022]
Abstract
To clarify the role of urokinase plasminogen activator (uPA) in the mechanisms of regulating sperm motility and the ability of fertilizing, we investigated the quantities and activities of uPA in human seminal plasma and on the membrane of spermatozoa. Semens were harvested from 22 infertile patients with asthenospermia and 20 healthy fertile men according to WHO standards. To quantify the membrane-bound uPA in the samples, polyclonal antibodies against human urokinase were employed by means of a sandwich ELISA. The uPA activities in seminal plasma and on the surface of spermatozoa were determined using A-garose-Fibrine-Plate method and the experiment of immunological identification with polyclonal antibodies against urokinase. In lysates of spermatozoa, significantly lower levels of uPA (23.1 +/- 7.35 mu/10(6) cells) and uPA activity (5.13 +/- 3.85 mu/10(6) cells) were found in patient group as compared to healthy fertile men exhibiting normospermia (29.89 +/- 9.40 mu/10(6) cells and 10.17 +/- 6.18 mu/10(6) cells). In seminal plasma, uPA activity in patient group (2134 +/- 1581.3 IU/L) was also found significantly lower than that of normal group (3365 +/- 1859.5 IU/L). Positive correlations were observed between sperm motility and uPA quantities (r = 0.48, P < 0.005), as well as with uPA activities (r = 0.45, P < 0.005). Thus, it is inferred that membrane associated uPA on human spermatozoa may be related directly to sperm motility and fertility.
Collapse
Affiliation(s)
- X Huang
- Center of Reproductive Medicine, Tongji Medical University, Wuhan
| | | | | | | | | | | |
Collapse
|
29
|
Affiliation(s)
- H Maeda
- Department of Microbiology, Kumamoto University School of Medicine, Japan
| |
Collapse
|
30
|
Field SL, Khachigian LM, Sleigh MJ, Yang G, Vandermark SE, Hogg PJ, Chesterman CN. Extracellular matrix is a source of mitogenically active platelet-derived growth factor. J Cell Physiol 1996; 168:322-32. [PMID: 8707868 DOI: 10.1002/(sici)1097-4652(199608)168:2<322::aid-jcp11>3.0.co;2-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Platelet-derived growth factor (PDGF) is a chemotactic and mitogenic agent for fibroblasts and smooth muscle cells and plays a key role in the development of atherosclerotic lesions. PDGF is produced by a number of normal and transformed cell types and occurs as homo- or heterodimers of A and B polypeptide chains. Using Chinese hamster ovary (CHO) cells transfected with various forms of PDGF, we have previously shown that PDGF A(s) (short splice version) is secreted, PDGF A(l) (long splice version) predominantly extracellular matrix-associated, and PDGF B divided between medium, cells, and matrix. In the present study we have demonstrated the mitogenic activity of matrix-localized PDGF in artificial and more physiologically relevant models by culturing Balb/c-3T3 cells (3T3), human foreskin fibroblasts (HFF), and rabbit aortic smooth muscle cells (SMC) on extracellular matrix (ECM) laid down by PDGF-expressing CHO cells and human umbilical vein endothelial cells (HUVEC). These cells responded to the local growth stimulus of PDGF-containing CHO ECM and HUVEC ECM. We showed that 3T3 cells required proteolytic activity to utilize matrix-localized PDGF, as aprotinin and epsilon-ACA inhibited growth and 3T3 cells were shown to possess plasminogen activator activity. HFF and SMC did not appear to require proteolytic activity (including metalloproteinase and serine protease activity) as a prerequisite for mitogenesis but were able to access immobilized PDGF by contact with the matrix. An understanding of the mechanisms whereby the utilization of stored PDGF is controlled in situations of excessive cellular proliferation will aid in the development of therapy for these conditions.
Collapse
Affiliation(s)
- S L Field
- Centre for Thrombosis and Vascular Research, School of Pathology, Prince of Wales Hospital, University of New South Wales, Sydney, Australia
| | | | | | | | | | | | | |
Collapse
|
31
|
Abstract
The involvement of proteases in the metastatic spread of tumour cells and in tumour related processes, such as angiogenesis and ulceration, has been known for many decades. This chapter reviews the involvement of one proteolytic system--the plasminogen activation system--in tumour progression. In recent years, many biochemical properties of the various components of the plasminogen activation system have become known. These properties and the functional relationship between the components are discussed in the first section. Since interfering with proteolysis by tumour cells and by newly formed endothelial cells can be an objective for future therapy, experimental tumour models have been used to study the effects of inhibitors of plasminogen activation. The second section deals with this issue. Finally, the presence of the various components of the plasminogen activation system in human tumours is reviewed. Following the availability of specific ELISAs, antibodies and molecular probes, the content and the cellular distribution of the components of the plasminogen activation system have recently been mapped in various human tumours.
Collapse
Affiliation(s)
- T J de Vries
- Department of Pathology, University Hospital, Nijmegen, The Netherlands
| | | | | |
Collapse
|
32
|
Maeda H, Akaike T, Wu J, Noguchi Y, Sakata Y. Bradykinin and nitric oxide in infectious disease and cancer. IMMUNOPHARMACOLOGY 1996; 33:222-30. [PMID: 8856154 DOI: 10.1016/0162-3109(96)00063-x] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Vascular pathophysiology at the sites of bacterial infection and cancerous tissues share numerous common events similar to inflammatory tissue. Among them enhanced vascular permeability is the universal and hallmark event mediated by bradykinin. All 16 or more bacterial or fungal proteases we have examined activated one or more steps of the kinin generating Hageman-factor-kallikrein cascade. In the meantime, most of the microbial proteases rapidly inactivated various plasma inhibitors such as alpha 1-protease inhibitor and alpha 2-macroglobulin. In addition to the extracellular proteases, bacterial cell wall components (negatively charged LPS) of gram-negative bacteria and teichoic acid moieties of gram-positive bacteria activate the Hageman-factor-kallikrein system and exert hypotensive effects via kinin generation. Endotoxin (LPS) also induces nitric oxide synthase (NOS) which appears to exhibit a rather slow, but significant, effect in relaxing the vascular tone of the infected animal (thus hypotension). Furthermore, bacterial proteases can activate the matrix metalloproteinase (collagenase) resulting in exacerbation of tissue injury in the diseased animal. Many tumor cells or tissues excrete plasminogen activator, and hence activate plasminogen. The plasmin thus generated activates procollagenases, as well as the Hageman-factor-kallikrein system, resulting in pronounced extravasation. Fluid accumulation in pleural and ascitic carcinomatoses is largely due to the activated bradykinin-generating system. We can also demonstrate and control enhanced vascular permeability using kallikrein inhibitors, especially the polymer-conjugated soybean trypsin inhibitor which exhibits a prolonged plasma t1/2, kinin antagonists, NOS inhibitors, NO scavengers, inhibitors of prostaglandins and others. Bacterial proteases induce shock in mice which can be prevented by the soybean trypsin inhibitor by blocking the kallikrein-kinin cascade. Therapeutic use of kinin antagonists and a kallikrein inhibitor has been made for infectious diseases such as septicemia and in tumor pathology.
Collapse
Affiliation(s)
- H Maeda
- Department of Microbiology, Kumamoto University School of Medicine, Japan
| | | | | | | | | |
Collapse
|
33
|
Matsumoto H, Ueshima S, Fukao H, Mitsui Y, Matsuo O. Effects of lipopolysaccharide on the expression of fibrinolytic factors in an established cell line from human endothelial cells. Life Sci 1996; 59:85-96. [PMID: 8699925 DOI: 10.1016/0024-3205(96)00265-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Human endothelial cells express antithrombotic properties by producing prostacyclin, heparan sulphate and plasminogen activator (PA). Bacterial extract, such as lipopolysaccharide (LPS), damaged the blood vessels and destroyed the balance between the antithrombotic and thrombotic functions of endothelial cells. The fibrinolytic system is involved in antithrombotic functions. The TKM-33 cell line was established from human endothelial cells. In order to determine whether TKM-33 is a good fibrinolytic system endothelial cell expression model, the expression of fibrinolytic factors in TKM-33 cells treated with or without LPS was studied. The endothelial cells which had not been treated with LPS produced and secreted a large amount of urokinase-type PA (u-PA), and small amounts of tissue-type PA (t-PA) and PA inhibitor-1 (PAI-1), which were identified immunohistochemically and by electrophoretic enzymography. Diisopropylfluorophosphate-treated 125I-u-PA bound specifically to acid-treated monolayered endothelial cells with a Kd of 2.83 +/- 0.61 nM, and Bmax of (0.11 +/- 0.01) x 10(6) sites/cell. u-PAR expression was detected in endothelial cells by Northern blot analysis. Thus, endothelial cells was shown to express u-PAR which binds u-PA specifically. In the binding assay, the stimulation of endothelial cells with 0.1, 1.0 and 10 micrograms/ml of LPS altered the Kd values to 6.04 +/- 0.71, 7.03 +/- 1.55 and 7.38 +/- 1.03 nM, respectively. However the Bmax values did not change significantly. Although LPS treatment increased u-PAR expression in endothelial cells in a dose-dependent manner, the expression of u-PA and t-PA mRNAs was not altered significantly. LPS stimulation (10 micrograms/ml) increased the expression of PAI-1 mRNA, significantly. The PA activity recovered from the cell surface fraction was not affected by LPS stimulation, but the PAI-1 activity was increased. These findings suggest that the established endothelial cell line, TKM-33, possesses the characteristics of endothelial cells and they express u-PAR on their cell surface, which is occupied by intrinsic u-PA secreted from the cells, and that treatment of endothelial cells with LPS changes the cell surface characteristics and inhibited the u-PAR expression thus promoting the prothrombotic function concomitantly with increased PAI-1 activity.
Collapse
Affiliation(s)
- H Matsumoto
- Department of Physiology, Kinki University School of Medicine, Osakasayama, Japan
| | | | | | | | | |
Collapse
|
34
|
Maeda H, Yamamoto T. Pathogenic mechanisms induced by microbial proteases in microbial infections. BIOLOGICAL CHEMISTRY HOPPE-SEYLER 1996; 377:217-26. [PMID: 8737987 DOI: 10.1515/bchm3.1996.377.4.217] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Most bacterial and fungal proteases excreted into infected hosts exhibit a wide range of pathogenic potentials ranging from pain, edema or even shock to translocation of bacteria from the site of infection into systemic circulation, thus resulting in septicemia. The basic mechanism or principle common to all these phenomena is explained by kinin generation, either directly from high- and/or low-molecular weight kininogens or indirectly via activation of the bradykinin generating cascade: i.e. Hageman factor-->activated Hageman factor-->prekallikrein-->kallikrein-->high-molecular weight kininogen-->bradykinin. Some bacterial proteases are also involved in activation of other host protease zymogens such as plasminogen, procollagenase (matrix metallo proteases) and proenzymes of the clotting system. Furthermore, most bacterial proteases are not only resistant to plasma protease inhibitors of the hosts, most of which belong to a group of serine protease inhibitors called serpins (serine protease inhibitors), but they also quickly inactivate serpins. Some bacterial proteases may also activate bacterial toxins thus rendering toxigenic pathogenesis. They are also capable of degrading immunoglobulins and components of the complement system and facilitate propagation of micro organisms. All in all, microbial proteases are very critical in enhancing pathogenesis of severe diseases. It is also noteworthy that bacterial cell wall components themselves, i.e. endotoxin (or lipopolysaccharide) of gram negative bacteria and teichoic/lipoteichoic acid of gram positive bacteria, are also able to activate the bradykinin generating cascade-involving activation of Hageman factor as mentioned above.
Collapse
Affiliation(s)
- H Maeda
- Department of Microbiology, Kumamoto University School of Medicine, Japan
| | | |
Collapse
|
35
|
Kost C, Benner K, Stockmann A, Linder D, Preissner KT. Limited plasmin proteolysis of vitronectin. Characterization of the adhesion protein as morpho-regulatory and angiostatin-binding factor. EUROPEAN JOURNAL OF BIOCHEMISTRY 1996; 236:682-8. [PMID: 8612645 DOI: 10.1111/j.1432-1033.1996.0682d.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The adhesion protein vitronectin is associated with extracellular matrices and serves as cofactor for plasminogen-activator inhibitor-1. Limited proteolysis by plasmin converts vitronectin into defined fragments which are detectable at sites of inflammation and angiogenesis. The loss and gain of binding functions of vitronectin fragments for macromolecular ligands was characterized in the present study. The initially generated 61--63-kDa vitronectin-(1--348)-fragment serves as typical binding component for plasminogen and binding function was lost upon carboxypeptidase B treatment indicating the importance of a C-terminal lysine. Complementary binding sites reside in isolated plasminogen kringles 1--3 (designated angiostatin) as deduced from direct binding and ligand blotting experiments. A synthetic vitronectin-(331--348)-peptide from the C-terminus of the 61--63-kDa fragment could mimic plasminogen and angiostatin binding. Also, the immobilized peptide bound tissue plasminogen-activator and mediated plasmin formation, comparable to fibrinogen-derived peptides. The 61--63-kDa vitronectin fragment was indistinguishable in its adhesive properties to intact vitronectin and bound active but not latent plasminogen-activator inhibitor-1. Late plasminolysis of vitronectin resulted in the processing of the N-terminal region of the protein with the generation of 42 kDa/35-kDa fragments that had Gly89 as new N-terminus and that were ineffective in promoting cell adhesion. Thus, at sites of cell-matrix interactions which become proteolytically modified by plasmin during inflammatory and angiogenic processes, vitronectin serves as plasminogen/angiostatin-binding factor. Due to this differential change in functions particularly at sites of deposition in the vascular system or at wound sites vitronectin is considered to be an important morpho-regulatory factor.
Collapse
Affiliation(s)
- C Kost
- Haemostasis Research Unit, Kerckhoff-Klinik, Bad Nauheim, Germany
| | | | | | | | | |
Collapse
|
36
|
Wilkins-Port CE, McKeown-Longo PJ. Heparan sulfate proteoglycans function in the binding and degradation of vitronectin by fibroblast monolayers. Biochem Cell Biol 1996; 74:887-97. [PMID: 9164657 DOI: 10.1139/o96-094] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Vitronectin, a 75-kDa plasma protein is also found in the extracellular matrix, where it is believed to promote cell adhesion and migration. In addition to its role in adhesion, matrix vitronectin is also believed to function as an opsonin promoting the clearance of thrombin-serpin complexes from the matrix. Vitronectin is cleared from the matrix by receptor-mediated endocytosis followed by lysosomal degradation, suggesting that cells can regulate the levels of vitronectin present in the matrix. However, the mechanism by which plasma vitronectin associates with the extracellular matrix remains unclear. Studies were conducted to define the binding site(s) for vitronectin in fibroblast cell layers. Sodium chlorate, a competitive inhibitor of proteoglycan sulfation, produced a dose-dependent decrease in both binding and degradation of vitronectin. This inhibition was reversible in that removal of chlorate returned both binding and degradation of vitronectin to near control levels within 24 h. The binding of vitronectin to cell layers was not dependent on cells because vitronectin bound directly to isolated matrix. Isolated matrices prepared from cell layers treated with sodium chlorate also exhibited a dose-dependent decrease in vitronectin binding, consistent with the binding site for vitronectin in the matrix being sulfated proteoglycans. Binding and degradation of vitronectin were also sensitive to the addition of exogenous heparin, suggesting that the heparin binding domain of vitronectin was mediating binding to the matrix. Incubating fibroblast monolayers with heparinase III resulted in a 40% decrease in binding and degradation of vitronectin. Taken together, the above findings suggest that vitronectin's binding to the matrix and its subsequent degradation are dependent on heparan sulfate proteoglycans.
Collapse
Affiliation(s)
- C E Wilkins-Port
- Department of Physiology and Cell Biology, Neil Hellman Medical Research Building, Albany Medical College of Union University, NY 12208, USA
| | | |
Collapse
|
37
|
Wilhelm O, Schmitt M, Höhl S, Senekowitsch R, Graeff H. Antisense inhibition of urokinase reduces spread of human ovarian cancer in mice. Clin Exp Metastasis 1995; 13:296-302. [PMID: 7606892 DOI: 10.1007/bf00133485] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Urokinase-type plasminogen activator (uPA) is a protease involved in the process of tissue remodelling and cell migration in vitro. To explore whether uPA is a prerequisite for human ovarian cancer spread in vivo the expression of uPA was suppressed in human ovarian cancer cells by antisense phosphorothioate oligonucleotides (PS-ODN). The suppression of uPA expression was dependent on PS-ODN concentration and only observed in the presence of liposomes. This phenomenon seemed to be due to the fact that PS-ODNs were taken up by the cancer cells only in concert with liposomes as studied by fluorescently-labeled PS-ODNs using flow cytofluorometry and laser scanning microscopy. uPA-deprived cancer cells exhibited a significantly reduced invasive capacity in vitro compared with untreated cancer cells or cells treated with control PS-ODNs (P = 0.003). The intraperitoneal spread of the cancer cells in vivo was significantly diminished when nude mice were treated with uPA antisense PS-ODNs in comparison with control mice (P = 0.009). These results suggest that uPA expression may be required for spread of human ovarian cancer and that its inhibition could provide a therapeutic approach.
Collapse
Affiliation(s)
- O Wilhelm
- Frauenklinik der Technischen Universität München, Germany
| | | | | | | | | |
Collapse
|
38
|
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.
Collapse
Affiliation(s)
- M Conese
- Dipartimento di Scienze Biomedicine e Oncologia Umana, Sezione di Patologia Generale Policlinico, Bari, Italy
| | | |
Collapse
|
39
|
Billström A, Hartley-Asp B, Lecander I, Batra S, Astedt B. The urokinase inhibitor p-aminobenzamidine inhibits growth of a human prostate tumor in SCID mice. Int J Cancer 1995; 61:542-7. [PMID: 7759160 DOI: 10.1002/ijc.2910610419] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Malignant cells possess a high degree of proteolytic activity in which the plasminogen activator system plays an important role. An increased expression of urokinase type plasminogen activator (uPA) is of significance for degradation of the extracellular tumor matrix, facilitating invasiveness and growth. Inhibition of the active site of uPA makes it possible to evaluate the significance of uPA in tumor growth. We report here experiments on a uPA-producing human prostate xenograft (DU 145) using a competitive inhibitor of uPA, p-aminobenzamidine. In vitro experiments with DU 145 cells showed that p-aminobenzamidine caused a dose-dependent inhibition of uPA activity. DU 145 cells were inoculated s.c. in SCID mice and, once tumors were established, treatment with p-aminobenzamidine added to drinking water was started and lasted for 23 days. Mice receiving 250 mg/kg/day of p-aminobenzamidine showed a clear decrease in tumor-growth rate compared to the non-treated mice, resulting in 64% lower final tumor weight. In addition, uPA-antigen levels in the membrane fractions of DU 145 tumors from p-aminobenzamidine-treated mice were found to be decreased by 59%. We also show that p-aminobenzamidine has an anti-proliferative effect in cell culture at low cell number, correlating with a dose-dependent decrease in uPA production. In conclusion, we show that a low-molecular-weight uPA-inhibitor, p-aminobenzamidine, has a growth-inhibitory effect on a solid uPA-producing tumor.
Collapse
Affiliation(s)
- A Billström
- Pharmacia Oncology Immunology, University Hospital, Lund, Sweden
| | | | | | | | | |
Collapse
|
40
|
Pappot H, Gårdsvoll H, Rømer J, Pedersen AN, Grøndahl-Hansen J, Pyke C, Brünner N. Plasminogen activator inhibitor type 1 in cancer: therapeutic and prognostic implications. BIOLOGICAL CHEMISTRY HOPPE-SEYLER 1995; 376:259-67. [PMID: 7662168 DOI: 10.1515/bchm3.1995.376.5.259] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Degradation of the extracellular matrix plays a crucial role in cancer invasion. This degradation is accomplished by the concerted action of several enzyme systems, including generation of the serine protease plasmin by the urokinase pathway of plasminogen activation, different types of collagenases and other metalloproteinases, and other extracellular enzymes. The degradative enzymes are involved also in tissue remodelling under non-malignant conditions, and the main difference appears to be that mechanisms which regulates these processes under normal conditions are defective in cancer. Specific inhibitors have been identified for most of the proteolytic enzymes, e.g. plasminogen activator inhibitors (PAI's) and tissue inhibitors of metalloproteinases (TIMP's). It has been contemplated that these inhibitors counteracted the proteolytic activity of the enzymes, thereby inhibiting extracellular tissue degradation which in turn should prevent tumor cell invasion. This review focuses on plasminogen inhibitor type 1 (PAI-1). It is described that PAI-1 is not produced by the epithelial cancer cell but by the stromal cells in the tumors, suggesting a concerted action between stroma and tumor cells in the processes controlling proteolysis in cancer. The specific localization of PAI-1 to the tumor stroma and in many cases to areas surrounding the tumor vessels has lead us to suggest that PAI-1 serves to protect the tumor stroma from the ongoing uPA-mediated proteolysis. This hypothesis is supported by recent clinical data showing increased levels of PAI-1 in metastases as compared to the primary tumor as well as data demonstrating that high levels of PAI-1 in tumor extracts from breast, lung, gastric and ovarian cancer is associated with a shorter overall survival.(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
Affiliation(s)
- H Pappot
- Finsen Laboratory, Rigshospitalet, Copenhagen-O, Denmark
| | | | | | | | | | | | | |
Collapse
|
41
|
|
42
|
Kramer MD, Schaefer B, Reinartz J. Plasminogen activation by human keratinocytes: molecular pathways and cell-biological consequences. BIOLOGICAL CHEMISTRY HOPPE-SEYLER 1995; 376:131-41. [PMID: 7612190 DOI: 10.1515/bchm3.1995.376.3.131] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Keratinocytes are the major cellular constituent of stratified epithelia. Defects in these epithelia are re-epithelialized by keratinocytes migrating from the edge of the defect into the wound. The cells form a monolayer with subsequent differentiation into a multilayered epithelium. It is thought that plasminogen activation by migrating keratinocytes is an important event during re-epithelialization. In the present report we summarize the studies on plasminogen activation by human keratinocytes in vitro and in vivo. Under the aspect of pericellular proteolysis the discussion is focused on the molecular mechanisms of plasminogen activation at the keratinocyte surface and on the cell-biological consequences of pericellular plasmin formation. We describe a cell surface-associated pathway of plasminogen activation which crucially depends on cell surface receptors for (pro)-uPA and plasmin(ogen). uPA bound to its receptor converts cell-bound plasminogen into the active protease plasmin. Compared to plasminogen activation in solution, activation at the keratinocyte cell surface is accelerated by a factor of approx. 7-10, and the plasmin generated and bound at the cell surface is protected against its specific inhibitor alpha 2-antiplasmin. Plasmin thus provided in the pericellular space leads to detachment of cultured keratinocytes from the growth substratum. Plasmin interferes with the adhesion of keratinocytes to fibrin, but not with the adhesion to collagen type I. By demonstrating that keratinocytes of the epithelial outgrowth in healing skin wounds express uPA and the uPA-R and that plasmin(ogen) is colocalized with uPA and/or uPA-R, indirect evidence is provided that this pathway may be operative in vivo. In view of previous findings that plasminogen activation is also observed under certain pathologic conditions in the epidermis, we conclude that plasminogen activation by keratinocytes is rather related to tissue damage and subsequent repair mechanisms than to a specific pathologic situation.
Collapse
Affiliation(s)
- M D Kramer
- Institut für Immunologie und Serologie, Laboratorium für Immunpathologie, Heidelberg, Germany
| | | | | |
Collapse
|
43
|
Rønne E, Høyer-Hansen G, Brünner N, Pedersen H, Rank F, Osborne CK, Clark GM, Danø K, Grøndahl-Hansen J. Urokinase receptor in breast cancer tissue extracts. Enzyme-linked immunosorbent assay with a combination of mono- and polyclonal antibodies. Breast Cancer Res Treat 1995; 33:199-207. [PMID: 7749147 DOI: 10.1007/bf00665944] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Urokinase plasminogen activator (uPA) is a proteolytic enzyme involved in degradation of the extracellular matrix during cancer invasion. The levels of uPA and its inhibitor PAI-1 in tumor extracts have previously been demonstrated to be of prognostic value in breast cancer as well as other types of cancer. We have previously characterized a specific cell surface receptor for uPA (uPAR) which strongly enhances the catalytic activity of uPA and is expressed during mammary cancer invasion. In order to quantitate uPAR in breast cancer tissue, we have now developed a sensitive enzyme-linked immunosorbent assay (ELISA), with polyclonal catching antibodies and three monoclonal detecting antibodies. The detection limit of the assay is approximately 0.16 fmol of uPAR in a volume of 100 microliters (1.6 pM). There is a linear relationship between signal and uPAR concentration up to at least 6.6 fmol per 100 microliters (66 pM). Both free uPAR and uPAR in complex with uPA is detected. The recovery of an internal uPAR standard in breast cancer tissue extracts is above 87%. The intra-assay and inter-assay variation coefficients are 7% and 13%. In order to find a suitable buffer for extraction of various components of the uPA-system from breast cancer tissue, we tested buffers which previously have been used for optimal extraction of estrogen receptor (A), uPA (B), and uPAR (C). Buffer A and B extracted approximately 30% and 50%, respectively, of the amount of uPAR extracted with buffer C.(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
Affiliation(s)
- E Rønne
- Finsen Laboratory, Rigshospitalet, Copenhagen, Denmark
| | | | | | | | | | | | | | | | | |
Collapse
|
44
|
Billström A, Lecander I, Dagnaes-Hansen F, Dahllöf B, Stenram U, Hartley-Asp B. Differential expression of uPA in an aggressive (DU 145) and a nonaggressive (1013L) human prostate cancer xenograft. Prostate 1995; 26:94-104. [PMID: 7531848 DOI: 10.1002/pros.2990260206] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Prostate cancer has a slow growing noninvasive phase, but, in general, is invasive on diagnosis. An initial step in the invasion of surrounding normal tissue is the activity of proteolytic enzymes such as components of the plasminogen activator system (PA). In cell culture, the primary human prostate cancer cell line 1013L expressed no urokinase type-PA (uPA), while DU 145, a cell line derived from a metastatic lesion, expressed high levels of uPA. The DU 145 cells grew easily as xenografts but the establishment of 1013L in the SCID mice was possible only with the aid of a gelatin sponge (Spongostan). The latency period was 42-64 days, followed by a slow growth phase before a fast growth phase occurred. This fast growth phase was characterized by rapid degeneration of tumor tissue, while high proliferation occurred around the blood vessels. On serial transplantation of tumor material, the growth pattern was similar. Furthermore, the 1013L tumor was encapsulated by connective tissue and no invasiveness could be detected. We found that 1013L tumor homogenates had hardly detectable levels of uPA, i.e., 300-fold lower than we found in the invasive prostate xenograft DU 145. In addition, no expression of uPA was found in the plasma of 1013L tumor-bearing mice whilst uPA antigen was detected in the plasma of DU 145 tumor-bearing mice. In conclusion, the 1013L cell line, which exhibits a nonaggressive pattern, could be a good model for studying progression of prostate cancer to a more aggressive phenotype in vivo and in vitro.
Collapse
|
45
|
Noda-Heiny H, Daugherty A, Sobel BE. Augmented urokinase receptor expression in atheroma. Arterioscler Thromb Vasc Biol 1995; 15:37-43. [PMID: 7749814 DOI: 10.1161/01.atv.15.1.37] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Smooth muscle cell proliferation and migration into neointima are hallmarks of atherogenesis. However, mechanisms responsible have not yet been fully elucidated. One potential mediator of both smooth muscle cell proliferation and migration is activation of plasminogen by activators bound to receptors on cells within the vessel wall. To determine whether vascular smooth muscle cells within atheroma express the receptor for urokinase-type plasminogen activator (uPA-R), we characterized atheroma in cholesterol-fed New Zealand White rabbits and human subjects by immunostaining. Intense immunostaining of uPA-R was observed throughout the neointima in both rabbit and human atherosclerotic lesions with the use of a monoclonal antibody to uPA-R. uPA-R was not detectable in normal arterial tissues. uPA-R was localized to macrophages and neointimal smooth muscle cells identified by immunostaining in serial sections. Furthermore, uPA-R protein in extracts from atheroma was present in at least a ninefold greater quantity compared with extracts from normal vessels, as shown by Western blotting. Expression of uPA-R mRNA in migrating vascular smooth muscle cells did not increase significantly. Thus, altered posttranscriptional regulation may be contributing to the increased uPA-R. In vitro, antibodies to uPA-R delayed the migration of cultured vascular smooth muscle cells. Our results suggest that increased cell-surface uPA-R contributes to pericellular proteolysis and consequently increased neointimalization secondary to increased vascular smooth muscle cell migration in atheroma.
Collapse
Affiliation(s)
- H Noda-Heiny
- Cardiovascular Division, Washington University School of Medicine, St Louis, MO 63110, USA
| | | | | |
Collapse
|
46
|
García-Rocha M, Avila J, Armas-Portela R. Tissue-type plasminogen activator (tPA) is the main plasminogen activator associated with isolated rat nerve growth cones. Neurosci Lett 1994; 180:123-6. [PMID: 7700563 DOI: 10.1016/0304-3940(94)90502-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Different studies in tissue culture have shown the involvement of plasminogen activators (PAs) in nerve growth-cone migration. We have studied PA activity associated with isolated rat brain growth cones. Fibrin-agarose zymographies show that tissue-type PA (tPA) is the main PA associated with these structures. After fractionation of growth cones, a slightly higher tPA activity was found associated with the particulate fraction. The present findings support the requirement of this protease for neurite growth.
Collapse
Affiliation(s)
- M García-Rocha
- Centro de Biología Molecular Severo Ochoa, CSIC-UAM, Facultad de Ciencias, Universidad Autónoma de Madrid, Spain
| | | | | |
Collapse
|
47
|
Vaheri A, Tapiovaara H, Myöhänen H, Bizik J. Alpha 2-macroglobulin in the regulation of pericellular plasminogen activation of human tumor cells. Ann N Y Acad Sci 1994; 737:409-18. [PMID: 7524411 DOI: 10.1111/j.1749-6632.1994.tb44327.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- A Vaheri
- Department of Virology, University of Helsinki, Finland
| | | | | | | |
Collapse
|
48
|
Bradley WA, Booyse FM, Gianturco SH. Fibrinolytic and thrombotic factors in atherosclerosis and IHD: the influence of triglyceride rich lipoproteins (TGRLP). Atherosclerosis 1994; 108 Suppl:S31-9. [PMID: 7802727 DOI: 10.1016/0021-9150(94)90151-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
TGRLP interactions with the endothelium may increase the likelihood that a suppressed fibrinolytic capacity and/or an increased procoagulant activity enhances the risk for an ischemic event, that is, for the production of a focal thrombus. The cellular mechanisms and characteristics of TGRLP in hyperlipemia and in the postprandial state that contribute to their potential pathology in IHD are considered.
Collapse
Affiliation(s)
- W A Bradley
- University of Alabama, Department of Medicine, Birmingham
| | | | | |
Collapse
|
49
|
Gibson PR, Rosella O, Rosella G, Young GP. Butyrate is a potent inhibitor of urokinase secretion by normal colonic epithelium in vitro. Gastroenterology 1994; 107:410-9. [PMID: 7518782 DOI: 10.1016/0016-5085(94)90166-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
BACKGROUND/AIMS Because the neutral protease urokinase is important in control of cell adhesion and migration, the effects of the physiologically relevant fermentation product butyrate on urokinase secretion by colonic epithelium were examined. METHODS Secreted and cell-associated levels of urokinase and plasminogen activator inhibitor 1 were measured in colonic crypt cells within 24 hours of isolation from macroscopically normal mucosa of normal or cancer-bearing colons. RESULTS Butyrate caused a concentration-dependent inhibition of both secreted (56% +/- 4% inhibition after 24-hour exposure to 1 mmol/L butyrate; n = 20; mean +/- SEM; P < 0.001) and cell-associated urokinase content (35% +/- 6%; P = 0.003). Acetate and propionate had minimal effects. Butyrate also stimulated plasminogen activator inhibitor 1 secretion by 25% +/- 7% (P = 0.013). Net urokinase activities were suppressed in supernates and cell homogenates by butyrate. Levels of transcripts for urokinase and the inhibitor changed with butyrate exposure in parallel to the levels of secretion of the respective proteins. Cells from the cancer group showed significantly reduced inhibitor secretion and abnormal responses to butyrate (greater inhibition of urokinase secretion and no stimulation of inhibitor secretion), probably reflecting the diffuse disturbance of colonic epithelial biology associated with colorectal cancer. CONCLUSIONS Butyrate has dual effects in markedly reducing colonic epithelial urokinase activity, and these may have important implications to understanding colonic epithelial physiology and the pathogenesis and treatment of colonic diseases.
Collapse
Affiliation(s)
- P R Gibson
- Department of Medicine, University of Melbourne, Royal Melbourne Hospital, Victoria, Australia
| | | | | | | |
Collapse
|
50
|
Del Vecchio S, Stoppelli MP, Carriero MV, Fonti R, Massa O, Li PY, Botti G, Cerra M, D'Aiuto G, Esposito G. In vitro receptor imaging for characterization of human solid tumors. Nucl Med Biol 1994; 21:771-4. [PMID: 9241653 DOI: 10.1016/0969-8051(94)90048-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Since many of the factors involved in tumor growth and progression act through a receptor-mediated mechanism, we applied in vitro receptor imaging techniques to study the intratumoral distribution and concentration of receptor-molecules having experimental biological relevance in such processes. Here we summarize the results of a study concerning the role of urokinase receptor (uPAR) in the acquisition of an invasive phenotype by tumor cells. Independently of the system studied, we demonstrated that in vitro receptor imaging techniques can be used to define the biological characteristics of human solid tumors and can contribute to clarify the complex network of ligand/receptor interactions leading to tumor spread.
Collapse
Affiliation(s)
- S Del Vecchio
- Medicina Nucleare, Universita degli Studi Federico II, Napoli, Italy
| | | | | | | | | | | | | | | | | | | |
Collapse
|