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Martins-Green M, Petreaca M, Wang L. Chemokines and Their Receptors Are Key Players in the Orchestra That Regulates Wound Healing. Adv Wound Care (New Rochelle) 2013; 2:327-347. [PMID: 24587971 DOI: 10.1089/wound.2012.0380] [Citation(s) in RCA: 93] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2013] [Indexed: 12/13/2022] Open
Abstract
SIGNIFICANCE Normal wound healing progresses through a series of overlapping phases, all of which are coordinated and regulated by a variety of molecules, including chemokines. Because these regulatory molecules play roles during the various stages of healing, alterations in their presence or function can lead to dysregulation of the wound-healing process, potentially leading to the development of chronic, nonhealing wounds. RECENT ADVANCES A discovery that chemokines participate in a variety of disease conditions has propelled the study of these proteins to a level that potentially could lead to new avenues to treat disease. Their small size, exposed termini, and the fact that their only modifications are two disulfide bonds make them excellent targets for manipulation. In addition, because they bind to G-protein-coupled receptors (GPCRs), they are highly amenable to pharmacological modulation. CRITICAL ISSUES Chemokines are multifunctional, and in many situations, their functions are highly dependent on the microenvironment. Moreover, each specific chemokine can bind to several GPCRs to stimulate the function, and both can function as monomers, homodimers, heterodimers, and even oligomers. Activation of one receptor by any single chemokine can lead to desensitization of other chemokine receptors, or even other GPCRs in the same cell, with implications for how these proteins or their receptors could be used to manipulate function. FUTURE DIRECTIONS Investment in better understanding of the functions of chemokines and their receptors in a local context can reveal new ways for therapeutic intervention. Understanding how different chemokines can activate the same receptor and vice versa could identify new possibilities for drug development based on their heterotypic interactions.
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Affiliation(s)
- Manuela Martins-Green
- Department of Cell Biology and Neuroscience, University of California, Riverside, California
| | - Melissa Petreaca
- Department of Cell Biology and Neuroscience, University of California, Riverside, California
| | - Lei Wang
- Department of Cell Biology and Neuroscience, University of California, Riverside, California
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Bai KJ, Chen BC, Pai HC, Weng CM, Yu CC, Hsu MJ, Yu MC, Ma HP, Wu CH, Hong CY, Kuo ML, Lin CH. Thrombin-induced CCN2 expression in human lung fibroblasts requires the c-Src/JAK2/STAT3 pathway. J Leukoc Biol 2013; 93:101-112. [DOI: 10.1189/jlb.0911449] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023] Open
Abstract
Abstract
Thrombin might activate c-Src to induce JAK2 activation, which causes STAT3 activation, inducing CCN2 expression in human lung fibroblasts.
Thrombin is a multifunctional serine protease and an important fibrotic mediator that induces CCN2 expression. We previously showed that thrombin induces CCN2 expression via an ASK1-dependent JNK/AP-1 pathway in human lung fibroblasts. In this study, we further investigated the roles of c-Src, JAK2, and STAT3 in thrombin-induced CCN2 expression. Thrombin-induced CCN2 expression and CCN2-Luc activity were attenuated by a JAK inhibitor (AG490) and JAK2DN, STAT3DN, and the STAT decoy ODN. Moreover, transfection of cells with a CCN2-mtSTAT-Luc construct inhibited thrombin-induced CCN2-Luc activity. Treatment of cells with thrombin caused JAK2 phosphorylation at Tyr1007/1008 and STAT3 phosphorylation at Tyr705 in time-dependent manners. Thrombin-induced STAT3 phosphorylation was inhibited by AG490 and JAK2DN. Thrombin-induced STAT3 binding to the CCN2 promoter was analyzed by a DNA-binding affinity pull-down assay. In addition, thrombin-induced CCN2 expression and CCN2-Luc activity were inhibited by c-SrcDN and PP2 (an Src inhibitor). Transfection of cells with c-SrcDN also inhibited thrombin-induced JAK2 and STAT3 phosphorylation. Taken together, these results indicate that thrombin might activate c-Src to induce JAK2 activation, which in turn, causes STAT3 activation, and finally induces CCN2 expression in human lung fibroblasts.
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Affiliation(s)
- Kua-Jen Bai
- Department of Pulmonary Medicine, Taipei Medical University–Wanfang Hospital, Taipei Medical University , Taipei, Taiwan
- School of Respiratory Therapy, Taipei Medical University , Taipei, Taiwan
| | - Bing-Chang Chen
- School of Respiratory Therapy, Taipei Medical University , Taipei, Taiwan
| | - Hui-Chen Pai
- Graduate Institute of Medical Sciences, Taipei Medical University , Taipei, Taiwan
| | - Chih-Ming Weng
- Graduate Institute of Medical Sciences, Taipei Medical University , Taipei, Taiwan
| | - Chung-Chi Yu
- Graduate Institute of Medical Sciences, Taipei Medical University , Taipei, Taiwan
| | - Ming-Jen Hsu
- Graduate Institute of Medical Sciences, Taipei Medical University , Taipei, Taiwan
- Department of Pharmacology, College of Medicine, Taipei Medical University , Taipei, Taiwan
| | - Ming-Chih Yu
- Department of Pulmonary Medicine, Taipei Medical University–Wanfang Hospital, Taipei Medical University , Taipei, Taiwan
- School of Respiratory Therapy, Taipei Medical University , Taipei, Taiwan
| | - Hon-Ping Ma
- Taipei Medical University–Shuang Ho Hospital , New Taipei City, Taiwan
| | - Chih-Hsiung Wu
- Taipei Medical University–Shuang Ho Hospital , New Taipei City, Taiwan
| | - Chuang-Ye Hong
- Department of Pulmonary Medicine, Taipei Medical University–Wanfang Hospital, Taipei Medical University , Taipei, Taiwan
| | - Min-Liang Kuo
- Angiogenesis Research Center, Laboratory of Molecular and Cellular Toxicology, Institute of Toxicology, College of Medicine, National Taiwan University , Taipei, Taiwan
| | - Chien-Huang Lin
- Department of Pulmonary Medicine, Taipei Medical University–Wanfang Hospital, Taipei Medical University , Taipei, Taiwan
- Graduate Institute of Medical Sciences, Taipei Medical University , Taipei, Taiwan
- Taipei Medical University–Shuang Ho Hospital , New Taipei City, Taiwan
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Cattaneo F, Iaccio A, Guerra G, Montagnani S, Ammendola R. NADPH-oxidase-dependent reactive oxygen species mediate EGFR transactivation by FPRL1 in WKYMVm-stimulated human lung cancer cells. Free Radic Biol Med 2011; 51:1126-36. [PMID: 21708247 DOI: 10.1016/j.freeradbiomed.2011.05.040] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Revised: 05/25/2011] [Accepted: 05/31/2011] [Indexed: 01/23/2023]
Abstract
Cross talk between unrelated cell surface receptors, such as G-protein-coupled receptors (GPCR) and receptor tyrosine kinases (RTK), is a crucial signaling mechanism to expand the cellular communication network. We investigated the ability of the GPCR formyl peptide receptor-like 1 (FPRL1) to transactivate the RTK epidermal growth factor receptor (EGFR) in CaLu-6 cells. We observed that stimulation with WKYMVm, an FPRL1 agonist isolated by screening synthetic peptide libraries, induces EGFR tyrosine phosphorylation, p47(phox) phosphorylation, NADPH-oxidase-dependent superoxide generation, and c-Src kinase activity. As a result of EGFR transactivation, phosphotyrosine residues provide docking sites for recruitment and triggering of the STAT3 pathway. WKYMVm-induced EGFR transactivation is prevented by the FPRL1-selective antagonist WRWWWW, by pertussis toxin (PTX), and by the c-Src inhibitor PP2. The critical role of NADPH-oxidase-dependent superoxide generation in this cross-talk mechanism is corroborated by the finding that apocynin or a siRNA against p22(phox) prevents EGFR transactivation and c-Src kinase activity. In addition, WKYMVm promotes CaLu-6 cell growth, which is prevented by PTX and by WRWWWW. These results highlight the role of FPRL1 as a potential target of new drugs and suggest that targeting both FPRL1 and EGFR may yield superior therapeutic effects compared with targeting either receptor separately.
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Affiliation(s)
- Fabio Cattaneo
- Dipartimento di Biochimica e Biotecnologie Mediche, Università degli Studi di Napoli Federico II, 80131 Napoli, Italy
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Abstract
STUDY DESIGN Surgically denucleated porcine intervertebral discs (IVD) were injected with BIOSTAT BIOLOGX Fibrin Sealant (FS), and the in vivo effects were assessed over time by histological, biochemical, and mechanical criteria. OBJECTIVE The objectives were to test whether the intradiscal injection of FS stimulates disc healing. SUMMARY OF BACKGROUND DATA Disc avascularity prevents the deposition of a provisional fibrin scaffold that typically facilitates soft tissue repair. Poor disc wound healing leads to disc damage accumulation and chronic inflammation characterized by overproduction of proinflammatory cytokines and proteolytic enzymes. METHODS Four lumbar IVDs from each of 31 Yucatan minipigs were randomized to untreated controls; degenerative injury (nucleotomy); and nucleotomy plus FS injection. Animals were killed at 1, 2, 3, 6, and 12 weeks postsurgery. IVDs were harvested to quantify (1) architecture using morphological and histological grading; (2) proteoglycan composition using DMMB assay; (3) cytokine content using ELISA; and (4) mechanical properties using quantitative pressure/volume testing. RESULTS There was progressive invasion of annular tissue into the nucleus of nucleotomy discs and concomitant reduction in proteoglycan content. By contrast, FS supplementation inhibited nuclear fibrosis and facilitated proteoglycan content recovery over time. FS discs synthesized significantly less TNF-α than degenerate discs (66% vs. 226%, P < 0.05) and had upregulation of IL-4 (310% vs. 166%) and TGF-β (400% vs. 117%) at 2 to 3 weeks posttreatment. At the third week postsurgery, the denucleated discs were less stiff than controls (pressure modulus 779.9 psi vs. 2754.8 psi; P < 0.05) and failed at lower pressures (250.5 psi vs. 492.5 psi; P < 0.05). The stiffness and leakage pressure of the FS-treated discs recovered to control values after 6 and 12 weeks, respectively. CONCLUSION FS facilitated structural, compositional, and mechanical repair of the surgically damaged IVD. These FS-derived benefits are likely due to its conductive scaffold properties and metabolically active constituents such as thrombin, factor XIII, and aprotinin acetate.
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Isenovic ER, Kedees MH, Haidara MA, Trpkovic A, Mikhailidis DP, Marche P. Involvement of ERK1/2 kinase in insulin-and thrombin-stimulated vascular smooth muscle cell proliferation. Angiology 2010; 61:357-64. [PMID: 20304866 DOI: 10.1177/0003319709358693] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
It is well recognized that the proliferation of vascular smooth muscle cells (VSMCs) is a key event in the pathogenesis of various vascular diseases, including atherosclerosis and hypertension. We have previously shown that among extracellular signal-regulated protein kinases (ERKs), the 42- and 44-kDa isoforms (ERK1/2) participate in the cellular mitogenic machinery triggered by several VSMCs activators, including insulin (INS) and thrombin (Thr). However, understanding of the intracellular signal transduction pathways involved is incomplete. This review considers the recent findings in INS and Thr signaling mechanisms that modulate the proliferation of VSMCs with particular emphasis on the ERK1/2 signaling pathway, an important mediator of VSMCs hypertrophy and vascular disease. Moreover, because the ERK1/2 pathway have been acknowledged as an important mediator of VSMCs hypertrophy, ERK1/2 is identified as a key target for novel therapeutic interventions to minimize irreversible tissue damage associated with hypertension and atherosclerosis.
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Affiliation(s)
- Esma R Isenovic
- Vinca Institute of Nuclear Sciences, University of Belgrade, Laboratory for Molecular Genetics and Radiobiology, Belgrade, Serbia.
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Petreaca ML, Yao M, Liu Y, DeFea K, Martins-Green M. Transactivation of vascular endothelial growth factor receptor-2 by interleukin-8 (IL-8/CXCL8) is required for IL-8/CXCL8-induced endothelial permeability. Mol Biol Cell 2007; 18:5014-23. [PMID: 17928406 PMCID: PMC2096609 DOI: 10.1091/mbc.e07-01-0004] [Citation(s) in RCA: 157] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2007] [Revised: 09/28/2007] [Accepted: 10/02/2007] [Indexed: 12/30/2022] Open
Abstract
Interleukin-8 (IL-8/CXCL8) is a chemokine that increases endothelial permeability during early stages of angiogenesis. However, the mechanisms involved in IL-8/CXCL8-induced permeability are poorly understood. Here, we show that permeability induced by this chemokine requires the activation of vascular endothelial growth factor receptor-2 (VEGFR2/fetal liver kinase 1/KDR). IL-8/CXCL8 stimulates VEGFR2 phosphorylation in a VEGF-independent manner, suggesting VEGFR2 transactivation. We investigated the possible contribution of physical interactions between VEGFR2 and the IL-8/CXCL8 receptors leading to VEGFR2 transactivation. Both IL-8 receptors interact with VEGFR2 after IL-8/CXCL8 treatment, and the time course of complex formation is comparable with that of VEGFR2 phosphorylation. Src kinases are involved upstream of receptor complex formation and VEGFR2 transactivation during IL-8/CXCL8-induced permeability. An inhibitor of Src kinases blocked IL-8/CXCL8-induced VEGFR2 phosphorylation, receptor complex formation, and endothelial permeability. Furthermore, inhibition of the VEGFR abolishes RhoA activation by IL-8/CXCL8, and gap formation, suggesting a mechanism whereby VEGFR2 transactivation mediates IL-8/CXCL8-induced permeability. This study points to VEGFR2 transactivation as an important signaling pathway used by chemokines such as IL-8/CXCL8, and it may lead to the development of new therapies that can be used in conditions involving increases in endothelial permeability or angiogenesis, particularly in pathological situations associated with both IL-8/CXCL8 and VEGF.
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Affiliation(s)
- Melissa L. Petreaca
- *Graduate Program in Cell, Molecular, and Developmental Biology
- Department of Cell Biology and Neuroscience, and
| | - Min Yao
- Department of Cell Biology and Neuroscience, and
| | - Yan Liu
- Department of Cell Biology and Neuroscience, and
| | - Kathryn DeFea
- *Graduate Program in Cell, Molecular, and Developmental Biology
- Division of Biomedical Sciences, University of California, Riverside, Riverside, CA 92521
| | - Manuela Martins-Green
- *Graduate Program in Cell, Molecular, and Developmental Biology
- Department of Cell Biology and Neuroscience, and
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Zheng L, Martins-Green M. Molecular mechanisms of thrombin-induced interleukin-8 (IL-8/CXCL8) expression in THP-1-derived and primary human macrophages. J Leukoc Biol 2007; 82:619-29. [PMID: 17586662 DOI: 10.1189/jlb.0107009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Under normal conditions, macrophages provide essential innate immune surveillance in tissues. These cells also play key functions during wound healing and in pathological conditions. When macrophages are exposed to thrombin, an enzyme released from leaky blood vessels, they are stimulated to produce inflammatory cytokines, which are critical for wound healing and can also facilitate tumor growth and invasion. Using antibody cytokine arrays, we identified IL-8/CXCL8, a chemokine that plays important functions in inflammation and angiogenesis and consequently in healing and tumor development, as one of the cytokines that is highly stimulated in macrophages by thrombin. Here, we investigated the signal transduction mechanism by which thrombin stimulates IL-8/CXCL8 expression in THP-1-derived and primary human macrophages. We show that JNK is a crucial mediator of the thrombin signaling pathways in macrophages, and the activation of JNK is dependent on stimulation of the Rho small GTPase. The thrombin-induced Rho/JNK cascade is a novel signaling cascade for IL-8/CXCL8 transcription activation. Understanding the molecular mechanism by which thrombin controls the expression of inflammatory cytokines in macrophages can lead to therapeutic interventions, which can provide better management of healing, inflammation, and tumorigenesis.
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Affiliation(s)
- Lei Zheng
- Department of Cell Biology and Neuroscience, University of California Riverside, Riverside, CA 92521, USA
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Huang J, Hu J, Bian X, Chen K, Gong W, Dunlop NM, Howard OMZ, Wang JM. Transactivation of the epidermal growth factor receptor by formylpeptide receptor exacerbates the malignant behavior of human glioblastoma cells. Cancer Res 2007; 67:5906-13. [PMID: 17575160 DOI: 10.1158/0008-5472.can-07-0691] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The G protein-coupled formylpeptide receptor (FPR), which mediates leukocyte migration in response to bacterial and host-derived chemotactic peptides, promotes the chemotaxis, survival, and tumorigenesis of highly malignant human glioblastoma cells. Because glioblastoma cells may also express other receptors for growth signals, such as the epidermal growth factor (EGF) receptor (EGFR), we investigated the role of EGFR in the signaling cascade of FPR and how two receptors cross-talk to exacerbate tumor growth. We found that N-formyl-methionyl-leucyl-phenylalanine, an FPR agonist peptide, rapidly induced EGFR phosphorylation at tyrosine residue (Tyr) 992, but not residues 846, 1068, or 1173, in glioblastoma cells, whereas all these residues were phosphorylated after only EGF treatment. The FPR agonist-induced EGFR phosphorylation in tumor cells was dependent on the presence of FPR as well as Galphai proteins, and was controlled by Src tyrosine kinase. The transactivation of EGFR contributes to the biological function of FPR in glioblastoma cells because inhibition of EGFR phosphorylation significantly reduced FPR agonist-induced tumor cell chemotaxis and proliferation. Furthermore, depletion of both FPR and EGFR by short interference RNA abolished the tumorigenesis of the glioblastoma cells. Our study indicates that the glioblastoma-promoting activity of FPR is mediated in part by transactivation of EGFR and the cross-talk between two receptors exacerbates the malignant phenotype of tumor cells. Thus, targeting both receptors may yield antiglioblastoma agents superior to those targeting one of them.
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Affiliation(s)
- Jian Huang
- Laboratory of Molecular Immunoregulation, Cancer and Inflammation Program, Science Applications International Corporation-Frederick, National Cancer Institute at Frederick, Frederick, Maryland 21702-1201, USA
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Lin CH, Cheng HW, Hsu MJ, Chen MC, Lin CC, Chen BC. c-Src Mediates Thrombin-Induced NF-κB Activation and IL-8/CXCL8 Expression in Lung Epithelial Cells. THE JOURNAL OF IMMUNOLOGY 2006; 177:3427-38. [PMID: 16920985 DOI: 10.4049/jimmunol.177.5.3427] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
In this study, we examined the regulation of NF-kappaB activation and IL-8/CXCL8 expression by thrombin in human lung epithelial cells (EC). Thrombin caused a concentration-dependent increase in IL-8/CXCL8 release in a human lung EC line (A549) and primary normal human bronchial EC. In A549 cells, thrombin, SFLLRN-NH2 (a protease-activated receptor 1 (PAR1) agonist peptide), and GYPGQV-NH2 (a PAR4 agonist peptide), but not TFRGAP-NH2 (a PAR3 agonist peptide), induced an increase in IL-8/CXCL8-luciferase (Luc) activity. The thrombin-induced IL-8/CXCL8 release was attenuated by D-phenylalanyl-L-prolyl-L-arginine chloromethyl ketone (a thrombin inhibitor), U73122 (a phosphoinositide-phospholipase C inhibitor), Ro-32-0432 (a protein kinsase C alpha (PKC alpha) inhibitor), an NF-kappaB inhibitor peptide, and Bay 117082 (an IkappaB phosphorylation inhibitor). Thrombin-induced increase in IL-8/CXCL8-Luc activity was inhibited by the dominant-negative mutant of c-Src and the cells transfected with the kappaB site mutation of the IL-8/CXCL8 construct. Thrombin caused time-dependent increases in phosphorylation of c-Src at tyrosine 416 and c-Src activity. Thrombin-elicited c-Src activity was inhibited by Ro-32-0432. Stimulation of cells with thrombin activated IkappaB kinase alphabeta (IKK alphabeta), IkappaB alpha phosphorylation, IkappaB alpha degradation, p50 and p65 translocation from the cytosol to the nucleus, NF-kappaB-specific DNA-protein complex formation, and kappaB-Luc activity. Pretreatment of A549 cells with Ro-32-4032 and the dominant-negative mutant of c-Src DN inhibited thrombin-induced IKK alphabeta activity, kappaB-Luc activity, and NF-kappaB-specific DNA-protein complex formation. Further studies revealed that thrombin induced PKC alpha, c-Src, and IKK alphabeta complex formation. These results show for the first time that thrombin, acting through PAR1 and PAR4, activates the phosphoinositide-phospholipase C/PKC alpha/c-Src/IKK alphabeta signaling pathway to induce NF-kappaB activation, which in turn induces IL-8/CXCL8 expression and release in human lung EC.
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Affiliation(s)
- Chien-Huang Lin
- Graduate Institute of Medical Sciences, College of Medicine, Taipei Medical University, Taiwan
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Wong LS, Martins-Green M. Firsthand cigarette smoke alters fibroblast migration and survival: implications for impaired healing. Wound Repair Regen 2004; 12:471-84. [PMID: 15260813 DOI: 10.1111/j.1067-1927.2004.12403.x] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Although it is known that high levels of cigarette smoke lead to cell death, little is known about the effects of low-to-moderate levels of smoke components that are found in vivo, such as those experienced by cells in tissues. Clinical studies and experimental data show that smokers heal poorly and are more prone to develop fibrotic diseases. Here we show the effects of first-hand cigarette smoke on fibroblasts, cells that are critically involved in these processes. Using doses of smoke found in the tissues of smokers and a variety of cell and molecular approaches, we show that these doses of cigarette smoke do not cause cell death but rather stimulate fibroblasts to produce stress response and survival proteins such as interleukin-8, PKB/Akt, p53, and p21 that in turn contribute to an increase in cell survival. In addition, smoke-treated cells show a decrease in cell migration, which can be explained by the increased cell adhesion and alterations in cytoskeletal elements. We also show that these levels of smoke cause changes in mitochondrial morphology with a minimum loss of function and these changes are the result of exposure to reactive oxygen species. We conclude that the increase in cell survival may lead to a build-up of connective tissue in the area of a wound, potentially leading to delayed healing and/or fibrosis and that the alterations in the cytoskeleton and in cell adhesion result in inhibition of cell migration, a process that could lead to nonclosure of the wound for lack of proper fibroblast migration to form the healing tissue.
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Affiliation(s)
- Lina S Wong
- Department of Cell Biology and Neuroscience, University of California-Riverside, Riverside, CA 92521, USA
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Schaffner A, King CC, Schaer D, Guiney DG. Induction and antimicrobial activity of platelet basic protein derivatives in human monocytes. J Leukoc Biol 2004; 76:1010-8. [PMID: 15316029 DOI: 10.1189/jlb.0404261] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The antimicrobial activity of a number of chemokines has recently come into focus of research about innate immunity. We have previously shown that platelet basic protein (PBP), which gives rise to several antimicrobial peptides of platelets, is also expressed in human monocytes. In the present studies, we show that exposure of human monocytes to bacteria or microbial components (lipopolysaccharide and zymosan) induces a several-fold greater expression of derivates of PBP. Also, activation of proteinase-activated receptors (PARs) by thrombin or the synthetic peptide ligand SFLLRN of PAR-1 significantly increased PBP expression, presumably on the transcriptional level, as evidenced by higher mRNA levels. Derivates of PBP appeared to reach phago-lysosomes, as higher concentration was found in latex phagosomes isolated by a flotation method. By the gel-overlay technique, two bactericidal derivatives of PBP could be visualized, which were immunoreactive with anti-PBP antibody in Western blots. By matrix-assisted laser desorption/ionization time of flight and surface-enhanced laser desorption and ionization techniques, it was confirmed that the bands corresponded to PBP derivates. After immunofixation with a monoclonal antibody to PBP, the major peptide in zymosan-stimulated monocytes was identified to correspond by molecular weight to connective tissue-activating peptide III, which has been reported to be a major antimicrobial PBP derivate also in platelets. Our observations indicate that PBP and its derivates are constituents of the antimicrobial arsenal of human monocytes. Their increased expression after exposure to microorganisms allows a rapid host response to pathogens.
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Affiliation(s)
- Andreas Schaffner
- Division of Infectious Diseases, University of California San Diego, USA.
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Yeh M, Gharavi NM, Choi J, Hsieh X, Reed E, Mouillesseaux KP, Cole AL, Reddy ST, Berliner JA. Oxidized phospholipids increase interleukin 8 (IL-8) synthesis by activation of the c-src/signal transducers and activators of transcription (STAT)3 pathway. J Biol Chem 2004; 279:30175-81. [PMID: 15143062 DOI: 10.1074/jbc.m312198200] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Oxidized 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phosphorylcholine (Ox-PAPC) and its component phospholipids 1-palmitoyl-2-epoxyisoprostane-sn-glycero-3-phosphorylcholine (PEIPC) and 1-palmitoyl-2-(5-oxovaleroyl)-sn-glycero-3-phosphorylcholine induce endothelial cells to synthesize chemotactic factors, such as interleukin 8 (IL-8). We have shown recently that Ox-PAPC-mediated induction of IL-8 transcription is independent of NF-kappaB activation, a major transcription factor utilized by cytokines and lipopolysaccharide for the induction of IL-8 transcription. In this study, we provide evidence for the role of c-src in Ox-PAPC and, specifically, PEIPC-mediated IL-8 induction. Ox-PAPC and its component phospholipids induced a rapid and transient phosphorylation of c-src Tyr418, a hallmark of c-src activation, in human aortic endothelial cells (HAEC). Ox-PAPC-mediated IL-8 protein synthesis in HAEC was inhibited by Src family kinase inhibitors, PP1 and PP2, but not by an inactive analog, PP3. Transient expression of plasmids containing C-terminal Src kinase or kinase-deficient dominant-negative c-src resulted in a 72 and 50% reduction in Ox-PAPC-induced IL-8 promoter activation in human microvascular endothelial cells, respectively. In contrast, overexpression of v-src kinase resulted in a 4-fold increase in IL-8 promoter activation, without inducing NF-kappaB promoter activation. Furthermore, treatment of HAEC with Ox-PAPC and its component PEIPC induced the activation of STAT3 by phosphorylating Tyr705, a feature of STAT3 activation. STAT3 is a known downstream effector of c-src. Ox-PAPC-induced activation of STAT3 resulted in the translocation of STAT3 from the cytoplasm of HAEC into their nuclear compartment. Transient expression of a dominant-negative STAT3beta construct in HMEC strongly inhibited IL-8 induction by Ox-PAPC. Taken together, these data demonstrate the role of the c-src kinase/STAT3 pathway in Ox-PAPC-mediated IL-8 expression in endothelial cells.
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Affiliation(s)
- Michael Yeh
- Division of Cardiology, Department of Medicine, University of California, Los Angeles, California 90095, USA.
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Wong LS, Green HM, Feugate JE, Yadav M, Nothnagel EA, Martins-Green M. Effects of "second-hand" smoke on structure and function of fibroblasts, cells that are critical for tissue repair and remodeling. BMC Cell Biol 2004; 5:13. [PMID: 15066202 PMCID: PMC400727 DOI: 10.1186/1471-2121-5-13] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2003] [Accepted: 04/05/2004] [Indexed: 01/09/2023] Open
Abstract
Background It is known that "second-hand" cigarette smoke leads to abnormal tissue repair and remodelling but the cellular mechanisms involved in these adverse effects are not well understood. Fibroblasts play a major role in repair and remodelling. They orchestrate these processes by proliferating, migrating, and secreting proteins such as, cytokines, growth factors and extracellular matrix molecules. Therefore, we focus our studies on the effects of "second-hand" cigarette smoke on the structure and function of these cells. Results We used sidestream whole (SSW) smoke, a major component of "second-hand" smoke, primary embryonic fibroblasts, cells that behave very much like wound fibroblasts, and a variety of cellular and molecular approaches. We show that doses of smoke similar to those found in tissues cause cytoskeletal changes in the fibroblasts that may lead to a decrease in cell migration. In addition, we also show that these levels of cigarette smoke stimulate an increase in cell survival that is reflected in an increase and/or activation of stress/survival proteins such as cIL-8, grp78, PKB/Akt, p53, and p21. We further show that SSW affects the endomembrane system and that this effect is also accomplished by nicotine alone. Conclusions Taken together, our results suggest that: (i) SSW may delay wound repair because of the inability of the fibroblasts to migrate into the wounded area, leading to an accumulation of these cells at the edge of the wound, thus preventing the formation of the healing tissue; (ii) the increase in cell survival coupled to the decrease in cell migration can lead to a build-up of connective tissue, thereby causing fibrosis and excess scarring.
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Affiliation(s)
- Lina S Wong
- Department of Cell Biology and Neuroscience, University of California, Riverside, California, USA
- Division of Biomedical Sciences, University of California, Riverside, California, USA
| | - Harry Miguel Green
- Department of Cell Biology and Neuroscience, University of California, Riverside, California, USA
| | - Jo Ellen Feugate
- Department of Cell Biology and Neuroscience, University of California, Riverside, California, USA
| | - Madhav Yadav
- Department of Botany and Plant Sciences, University of California, Riverside, California, USA
| | - Eugene A Nothnagel
- Department of Botany and Plant Sciences, University of California, Riverside, California, USA
| | - Manuela Martins-Green
- Department of Cell Biology and Neuroscience, University of California, Riverside, California, USA
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14
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Li QJ, Yao M, Wong W, Parpura V, Martins-Green M. The N- and C-terminal peptides of hIL8/CXCL8 are ligands for hCXCR1 and hCXCR2. FASEB J 2004; 18:776-8. [PMID: 14766805 DOI: 10.1096/fj.02-1175fje] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Chemokines are small cytokines that function in immune responses, wound healing, and pathological conditions such as chronic inflammation and tumorigenesis. This multifunctionality has been attributed primarily to ligand interaction with multiple or dimerized receptors. However, multifunctionality could also result from interactions of the receptors with small peptides produced by processing of the chemokines. Chemokine peptides are functional in vivo, but it is not yet known whether they can interact with and activate their receptors. The work presented here examines the interactions between the two forms of human interleukin 8 (hIL-8), and its N- and C-peptides, with the chemokine receptors hCXCR1 and hCXCR2. We used a Tet-on retroviral system to introduce CXCR1 into mouse NIH 3T3 cells (that lack endogenous CXCR1) and monitored activation of this receptor by the ligands by using quantitative Ca2+ imaging and mitogen-activated protein kinase (MAPK) activation. We found that the N and C termini of the chemokine can stimulate the respective CXCR1 to induce intracellular Ca2+ release and MAPK activation independent of the other regions of the molecules. Furthermore, we showed that these peptides can also stimulate chemotaxis of several cell types, including primary human microvascular endothelial cells, and that this function is specific and mediated by hCXCR1 and/or hCXCR2. These findings advance understanding of the multifunctionality exhibited by chemokines, reveal a new mode of functional regulation, and may serve as the basis for therapeutic targeting.
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Affiliation(s)
- Qi-Jing Li
- Department of Cell Biology and Neuroscience, University of California, Riverside, California 92521, USA
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15
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Bobe R, Yin X, Roussanne MC, Stepien O, Polidano E, Faverdin C, Marche P. Evidence for ERK1/2 activation by thrombin that is independent of EGFR transactivation. Am J Physiol Heart Circ Physiol 2003; 285:H745-54. [PMID: 12730054 DOI: 10.1152/ajpheart.01042.2002] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Thrombin is involved in abnormal proliferation of vascular smooth muscle cells (VSMCs) associated with pathogenic vascular remodeling. Thrombin stimulation results in extracellular signal-regulated kinase (ERK)1/2 activation through transactivation of the epidermal growth factor receptor (EGFR). Here, using specific antibodies and inhibitors, we investigated the thrombin-induced phosphorylation of Src family kinases, nonreceptor proline-rich tyrosine kinase (Pyk2), EGFR, and ERK1/2. Our results show that Src and Pyk2 are involved upstream of the EGFR transactivation that is required for ERK1/2 phosphorylation. The investigation of the role of intracellular calcium concentration ([Ca2+]i) and calcium mobilization with the Ca2+ chelator BAPTA and thapsigargin, respectively, indicated that thrombin- and thapsigargin-induced phosphorylation of the EGFR but not ERK1/2 is dependent on an increase in [Ca2+]i. Moreover, only after BAPTA-AM pretreatment was thrombin-induced activation of ERK1/2 partially preserved from the effects of EGFR and PKC inhibition but not Src family kinase inhibition. These results suggest that BAPTA, by preventing [Ca2+]i elevation, unmasks a new pathway of Src family kinase-dependent thrombin-stimulated ERK1/2 phosphorylation that is independent of EGFR and PKC activation.
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Affiliation(s)
- Régis Bobe
- Unité Mixte de Recherche 7131, Centre Nationale de la Recherche Scientifique, Hôpital Broussais, 102 rue Didot, 75014 Paris, France
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16
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Natarajan K, Rajala MS, Chodosh J. Corneal IL-8 expression following adenovirus infection is mediated by c-Src activation in human corneal fibroblasts. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2003; 170:6234-43. [PMID: 12794155 DOI: 10.4049/jimmunol.170.12.6234] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Emerging evidence indicates that intracellular signaling cascades mediate entry of pathogenic adenoviruses into target host cells as well as some of the undesirable inflammatory responses to adenoviral gene vectors. We found that Ad19 infection of cultured human corneal fibroblasts induced IL-8 gene transcription independently of IL-1beta, TNF-alpha, and viral gene expression, suggesting that intracellular signaling events might mediate early inflammatory events in adenovirus keratitis. Heat but not UV light inactivation of the virus abrogated the effect of infection on IL-8 mRNA and protein levels, consistent with a viral binding-mediated mechanism. The tyrosine kinase inhibitor herbimycin blocked Ad19-induced IL-8 expression. Western blot analysis revealed tyrosine phosphorylation of the functionally related kinases c-Src and extracellular signal-regulated kinase (ERK) 1/2 in corneal fibroblasts within 15 min after infection. Respective inhibitors of these kinases, PP2 and PD98059, also blocked Ad19-induced IL-8 mRNA and protein expression. Application of inhibitors to Src and ERK kinase assays suggested an upstream relationship of c-Src to ERK. Finally, DNA microarray studies performed 1 h after Ad19 or mock infection of corneal fibroblasts in the presence or absence of the Src-specific inhibitor PP2 confirmed a relationship between c-Src and IL-8 expression in Ad19-infected corneal cells. c-Src may act as a global regulator of early proinflammatory host responses to Ad19 infection of the human cornea.
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Affiliation(s)
- Kanchana Natarajan
- Department of Ophthalmology, The Molecular Pathogenesis of Eye Infection Research Center, Dean A. McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
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17
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Li QJ, Yang SH, Maeda Y, Sladek FM, Sharrocks AD, Martins-Green M. MAP kinase phosphorylation-dependent activation of Elk-1 leads to activation of the co-activator p300. EMBO J 2003; 22:281-91. [PMID: 12514134 PMCID: PMC140103 DOI: 10.1093/emboj/cdg028] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
CBP/p300 recruitment to enhancer-bound complexes is a key determinant in promoter activation by many transcription factors. We present a novel mechanism of activating such complexes and show that pre-assembled Elk-1-p300 complexes become activated following Elk-1 phosphorylation by changes in Elk-1-p300 interactions rather than recruitment. It is known that Elk-1 binds to promoter in the absence of stimuli. However, it is unclear how activation of Elk-1 by mitogen-acivated protein kinase (MAPK)-mediated phosphorylation leads to targeted gene transactivation. We show that Elk-1 can interact with p300 in vitro and in vivo in the absence of a stimulus through the Elk-1 C-terminus and the p300 N-terminus. Phosphorylation on Ser383 and Ser389 of Elk-1 by MAPK enhances this basal binding but, most importantly, Elk-1 exhibits new interactions with p300. These interaction changes render a strong histone acetyltransferase activity in the Elk-1-associated complex that could play a critical role in chromatin remodeling and gene activation. The pre-assembly mechanism may greatly accelerate transcription activation, which is important in regulation of expression of immediate-early response genes, in particular those involved in stress responses.
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Affiliation(s)
| | - Shen-Hsi Yang
- Department of Cell Biology and Neuroscience, University of California, Riverside, CA 92521, USA and
School of Biological Sciences, University of Manchester, 2.205 Stopford Building, Oxford Road, Manchester M13 9PT, UK Corresponding author e-mail:
| | | | | | - Andrew D. Sharrocks
- Department of Cell Biology and Neuroscience, University of California, Riverside, CA 92521, USA and
School of Biological Sciences, University of Manchester, 2.205 Stopford Building, Oxford Road, Manchester M13 9PT, UK Corresponding author e-mail:
| | - Manuela Martins-Green
- Department of Cell Biology and Neuroscience, University of California, Riverside, CA 92521, USA and
School of Biological Sciences, University of Manchester, 2.205 Stopford Building, Oxford Road, Manchester M13 9PT, UK Corresponding author e-mail:
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18
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Sabri A, Short J, Guo J, Steinberg SF. Protease-activated receptor-1-mediated DNA synthesis in cardiac fibroblast is via epidermal growth factor receptor transactivation: distinct PAR-1 signaling pathways in cardiac fibroblasts and cardiomyocytes. Circ Res 2002; 91:532-9. [PMID: 12242272 DOI: 10.1161/01.res.0000035242.96310.45] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Proteases elaborated by inflammatory cells in the heart would be expected to drive cardiac fibroblasts to proliferate, but protease-activated receptor (PAR) function in cardiac fibroblasts has never been considered. This study demonstrates that PAR-1 is the only known PAR family member functionally expressed by cardiac fibroblasts and that PAR-1 activation by thrombin leads to increased DNA synthesis in cardiac fibroblasts. The increase in DNA synthesis induced by PAR-1 substantially exceeds the effects of other G protein-coupled receptor agonists in this cell type. PAR-1 stimulates phosphoinositide hydrolysis and mobilizes intracellular calcium via pertussis toxin (PTX)-sensitive and PTX-insensitive pathways. Activation of PAR-1 leads to an increase in Src, Fyn, and epidermal growth factor receptor (EGFR) phosphorylation, with EGFR receptor transactivation by Src family kinases the major mechanism for PAR-1-dependent activation of extracellular signal-regulated kinase, p38-mitogen-activated protein kinase, and protein kinase B. Activation of PAR-1 also leads to an increase in DNA synthesis. PAR-1 signaling is highly contextual in nature, inasmuch as PAR-1 activates extracellular signal-regulated kinase and only weakly stimulates protein kinase B via a pathway that does not involve EGFR transactivation in cardiomyocytes. PAR-1 responses in cardiac fibroblasts and cardiomyocytes are predicted to contribute importantly to remodeling during cardiac injury and/or inflammation.
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Affiliation(s)
- Abdelkarim Sabri
- Department of Pharmacology, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
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19
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Feugate JE, Wong L, Li QJ, Martins-Green M. The CXC chemokine cCAF stimulates precocious deposition of ECM molecules by wound fibroblasts, accelerating development of granulation tissue. BMC Cell Biol 2002; 3:13. [PMID: 12057014 PMCID: PMC117214 DOI: 10.1186/1471-2121-3-13] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2001] [Accepted: 06/10/2002] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND During wound repair, fibroblasts orchestrate replacement of the provisional matrix formed during clotting with tenascin, cellular fibronectin and collagen III. These, in turn, are critical for migration of endothelial cells, keratinocytes and additional fibroblasts into the wound site. Fibroblasts are also important in the deposition of collagen I during scar formation. The CXC chemokine chicken Chemotactic and Angiogenic Factor (cCAF), is highly expressed by fibroblasts after wounding and during development of the granulation tissue, especially in areas where extracellular matrix (ECM) is abundant. We hypothesized that cCAF stimulates fibroblasts to produce these matrix molecules. RESULTS Here we show that this chemokine can stimulate precocious deposition of tenascin, fibronectin and collagen I, but not collagen III. Studies in culture and in vivo show that tenascin stimulation can also be achieved by the N-terminal 15 aas of the protein and occurs at the level of gene expression. In contrast, stimulation of fibronectin and collagen I both require the entire molecule and do not involve changes in gene expression. Fibronectin accumulation appears to be linked to tenascin production, and collagen I to decreased MMP-1 levels. In addition, cCAF is chemotactic for fibroblasts and accelerates their migration. CONCLUSIONS These previously unknown functions for chemokines suggest that cCAF, the chicken orthologue of human IL-8, enhances healing by rapidly chemoattracting fibroblasts into the wound site and stimulating them to produce ECM molecules, leading to precocious development of granulation tissue. This acceleration of the repair process may have important application to healing of impaired wounds.
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MESH Headings
- Angiogenesis Inducing Agents/pharmacology
- Angiogenesis Inducing Agents/physiology
- Animals
- Avian Proteins
- Cell Movement/drug effects
- Cell Movement/physiology
- Cells, Cultured
- Chemokines, CXC/pharmacology
- Chemokines, CXC/physiology
- Chick Embryo
- Collagen Type I/biosynthesis
- Collagen Type II/biosynthesis
- Cytokines/pharmacology
- Cytokines/physiology
- Extracellular Matrix Proteins/metabolism
- Fibroblasts/drug effects
- Fibroblasts/metabolism
- Fibroblasts/physiology
- Fibronectins/biosynthesis
- Granulation Tissue/chemistry
- Granulation Tissue/cytology
- Granulation Tissue/drug effects
- Granulation Tissue/physiology
- Humans
- Interleukin-8/pharmacology
- Interleukin-8/physiology
- Muscle, Smooth, Vascular/chemistry
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/physiology
- Peptides/pharmacology
- Peptides/physiology
- Sequence Homology, Amino Acid
- Tenascin/biosynthesis
- Wound Healing/drug effects
- Wound Healing/physiology
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Affiliation(s)
- Jo Ellen Feugate
- Department of Cell Biology and Neuroscience, University of California, Riverside, California, USA
| | - Lina Wong
- Department of Cell Biology and Neuroscience, University of California, Riverside, California, USA
| | - Qi-Jing Li
- Department of Cell Biology and Neuroscience, University of California, Riverside, California, USA
| | - Manuela Martins-Green
- Department of Cell Biology and Neuroscience, University of California, Riverside, California, USA
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20
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Abstract
Vascular smooth muscle cells (SMCs) are the principal cellular component of the normal artery and intimal lesions that develop in response to arterial injury. Several growth factors and their receptors participate in SMC activation, including the tyrosine kinase receptors for platelet-derived growth factor (PDGF) and basic fibroblast growth factor as well as the G-protein-coupled receptors (GPCRs) for thrombin and angiotensin II. During the last couple of years, it has become evident that GPCRs transactivate receptor tyrosine kinases, particularly the epidermal growth factor receptor (EGFR). The EGFR is not well characterized in terms of its role in vascular biology, but recent findings indicate that GPCRs induce EGFR transactivation in cultured vascular SMCs, perhaps by intracellular and extracellular pathways. Studies from our laboratory as well as two other groups have demonstrated that EGFR transactivation by different GPCR agonists and in different cell types, including SMCs, is mediated by heparin-binding EGF-like growth factor (HB-EGF). HB-EGF-dependent EGFR activation is blocked by heparin, a growth inhibitor of SMCs in vitro and in vivo. These data suggest that the EGFR may be important in the regulation of SMC function. The complexity of the GPCR-EGFR crosstalk, involving several different cell surface molecules and an inside-out signaling step, may provide novel targets for the control of SMC growth and intimal hyperplasia in the arterial injury response.
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Affiliation(s)
- A Kalmes
- Department of Surgery, University of Washington, Seattle 98195-6410, USA
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21
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Friedland JS, Constantin D, Shaw TC, Stylianou E. Regulation of interleukin‐8 gene expression after phagocytosis of zymosan by human monocytic cells. J Leukoc Biol 2001. [DOI: 10.1189/jlb.70.3.447] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Jon S. Friedland
- Department of Infectious Diseases, Imperial College of Science, Technology and Medicine (Hammersmith Campus), London, and
| | - Despina Constantin
- School of Biomedical Sciences and Institute of Cell Signalling, University Hospital, Nottingham, United Kingdom
| | - Terry C. Shaw
- Department of Infectious Diseases, Imperial College of Science, Technology and Medicine (Hammersmith Campus), London, and
| | - Eleni Stylianou
- School of Biomedical Sciences and Institute of Cell Signalling, University Hospital, Nottingham, United Kingdom
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22
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Madamanchi NR, Li S, Patterson C, Runge MS. Thrombin regulates vascular smooth muscle cell growth and heat shock proteins via the JAK-STAT pathway. J Biol Chem 2001; 276:18915-24. [PMID: 11278437 DOI: 10.1074/jbc.m008802200] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The growth-stimulating effects of thrombin are mediated primarily via activation of a G protein-coupled receptor, PAR-1. Because PAR-1 has no intrinsic tyrosine kinase activity, yet requires tyrosine phosphorylation events to induce mitogenesis, we investigated the role of the Janus tyrosine kinases (JAKs) in thrombin-mediated signaling. JAK2 was activated rapidly in rat vascular smooth muscle cells (VSMC) treated with thrombin, and signal transducers and activators of transcription (STAT1 and STAT3) were phosphorylated and translocated to the nucleus in a JAK2-dependent manner. AG-490, a JAK2-specific inhibitor, and a dominant negative JAK2 mutant inhibited thrombin-induced ERK2 activity and VSMC proliferation suggesting that JAK2 is upstream of the Ras/Raf/MEK/ERK pathway. To elucidate the functional significance of JAK-STAT activation, we studied the effect of thrombin on heat shock protein (Hsp) expression, based upon the following: 1) reports that thrombin stimulates reactive oxygen species production in VSMC; 2) the putative role of Hsps in modulating cellular responses to reactive oxygen species; and 3) the presence of functional STAT1/3-binding sites in Hsp70 and Hsp90beta promoters. Indeed, thrombin up-regulated Hsp70 and Hsp90 protein expression via enhanced binding of STATs to cognate binding sites in the Hsp70 and Hsp90 promoters. Together, these results suggest that JAK-STAT pathway activation is necessary for thrombin-induced VSMC growth and Hsp gene expression.
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Affiliation(s)
- N R Madamanchi
- Program in Molecular Cardiology, University of North Carolina, Chapel Hill, North Carolina 27599-7295
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23
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Crouch MF, Davy DA, Willard FS, Berven LA. Activation of endogenous thrombin receptors causes clustering and sensitization of epidermal growth factor receptors of swiss 3T3 cells without transactivation. J Cell Biol 2001; 152:263-73. [PMID: 11266444 PMCID: PMC2199612 DOI: 10.1083/jcb.152.2.263] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The G protein-coupled thrombin receptor can induce cellular responses in some systems by transactivating the epidermal growth factor (EGF) receptor. This is in part due to the stimulation of ectoproteases that generate EGF receptor ligands. We show here that this cannot account for the stimulation of proliferation or migration by thrombin of Swiss 3T3 cells. Thrombin has no direct effect on the activation state of the EGF receptor or of its downstream effectors. However, thrombin induces the subcellular clustering of the EGF receptor at filamentous actin-containing structures at the leading edge and actin arcs of migrating cells in association with other signaling molecules, including Shc and phospholipase Cgamma1. In these thrombin-primed cells, the subsequent migratory response to EGF is potentiated. Thrombin did not potentiate the EGF-stimulated EGF receptor phosphorylation. Thus, in Swiss 3T3 cells the G protein-coupled thrombin receptor can potentiate the EGF tyrosine kinase receptor response when activated by EGF, and this appears to be due to the subcellular concentration of the receptor with downstream effectors and not to the overall ability of EGF to induce receptor transphosphorylation. Thus, the EGF receptor subcellular localization which is altered by thrombin appears to be an important determinant of the efficacy of downstream EGF receptor signaling in cell migration.
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Affiliation(s)
- M F Crouch
- Molecular Signaling Group, John Curtin School of Medical Research, Australian National University, Canberra, A.C.T. 2601, Australia.
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24
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Abstract
p21-activated kinases (Paks) are effectors of the small GTPases Cdc42 and Rac, and are thought to mediate some of the cytoskeletal and transcriptional activities of these proteins. To localize activated Pak1 in cells, we developed an antibody directed against a phosphopeptide that is contained within the activation loop of Pak1. This antibody specifically recognizes the activated form of Pak1. Immunofluorescence analysis of NIH-3T3 cells coexpressing activated Cdc42 or Rac1 plus wild-type Pak1 shows that activated Pak1 accumulates at sites of focal adhesion, throughout filopodia and within the body and edges of lamellipodia. Platelet-derived growth factor stimulation of NIH-3T3 cells shows a pattern of Pak1 activation similar to that observed with Rac1. During closure of a fibroblast monolayer wound, Pak1 is rapidly activated and localizes to the leading edge of motile cells, then gradually tapers off as the wound closes. The activation of Pak1 by wounding is blocked by inhibitors of phosphatidylinositol 3-kinase, and Src family kinases, but not by an inhibitor of the epidermal growth factor receptor. These findings indicate that activated Pak1, and by extension, probably activated Cdc42 or Rac, accumulates at sites of cortical actin remodeling in motile fibroblasts.
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Affiliation(s)
- Mary Ann Sells
- Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111
| | - Amanda Pfaff
- Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111
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25
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Novel nuclear target for thrombin: activation of the Elk1 transcription factor leads to chemokine gene expression. Blood 2000. [DOI: 10.1182/blood.v96.12.3696] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractThrombin is primarily known for its role in homeostasis and thrombosis. However, this enzyme also plays important roles in wound healing and pathologic situations such as inflammation and tumorigenesis. Among the molecules stimulated by thrombin in these latter processes are the stress response proteins, chemokines. Chemokines are also known for their roles in inflammatory responses and tumor development. These correlative observations strongly suggest that chemokines may be mediators of some of thrombin's functions in these processes. Elucidation of the molecular mechanisms of stimulation of chemokines by thrombin may help to unravel the ways in which their expression can be modulated. Up-regulation of the chemokine 9E3/cCAF by thrombin occurs via its proteolytically activated receptor with subsequent transactivation of the epidermal growth factor receptor tyrosine kinase. This study shows that stimulation by thrombin very rapidly activates this chemokine at the transcriptional level, that 2 Elk1 binding elements located between −534 and −483 bp of the promoter are major thrombin response elements, that activation occurs via the Elk1 transcription factor, and that the latter is directly activated by MEK1/ERK2. The common occurrence of Elk1 binding domains in the promoters of immediate early response genes suggests that it may be characteristically involved in gene activation by stress-inducing agents.
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26
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Novel nuclear target for thrombin: activation of the Elk1 transcription factor leads to chemokine gene expression. Blood 2000. [DOI: 10.1182/blood.v96.12.3696.h8003696_3696_3706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Thrombin is primarily known for its role in homeostasis and thrombosis. However, this enzyme also plays important roles in wound healing and pathologic situations such as inflammation and tumorigenesis. Among the molecules stimulated by thrombin in these latter processes are the stress response proteins, chemokines. Chemokines are also known for their roles in inflammatory responses and tumor development. These correlative observations strongly suggest that chemokines may be mediators of some of thrombin's functions in these processes. Elucidation of the molecular mechanisms of stimulation of chemokines by thrombin may help to unravel the ways in which their expression can be modulated. Up-regulation of the chemokine 9E3/cCAF by thrombin occurs via its proteolytically activated receptor with subsequent transactivation of the epidermal growth factor receptor tyrosine kinase. This study shows that stimulation by thrombin very rapidly activates this chemokine at the transcriptional level, that 2 Elk1 binding elements located between −534 and −483 bp of the promoter are major thrombin response elements, that activation occurs via the Elk1 transcription factor, and that the latter is directly activated by MEK1/ERK2. The common occurrence of Elk1 binding domains in the promoters of immediate early response genes suggests that it may be characteristically involved in gene activation by stress-inducing agents.
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27
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Li QJ, Lu S, Ye RD, Martins-Green M. Isolation and characterization of a new chemokine receptor gene, the putative chicken CXCR1. Gene 2000; 257:307-17. [PMID: 11080597 DOI: 10.1016/s0378-1119(00)00385-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
This study delineates the isolation and characterization of a novel chemokine receptor gene, the putative chicken CXC receptor 1 (cCXCR1). Using a human CXCR1 probe, we isolated several positive clones from a chicken genomic library. One of the clones contained a fragment of approximately 5000bp that hybridized strongly with the hCXCR1 probe. This fragment was sequenced and subjected to a variety of computer analyses. The open reading frame for this gene predicts a seven transmembrane domain protein with all the characteristics of a chemokine receptor and with 67% sequence homology to hCXCR1, 65% to hCXCR2 and also with considerable sequence homology to other human chemokine receptors such as hCXCR4 (50%), hCCR2 (49%) and hCCR1 (49%). However, the homology to a previously isolated potential G-protein-coupled receptor for chickens (AvCRL1) is only 47%. Using 5' RACE, two transcription initiation sites were identified suggesting the potential for the expression of two protein isoforms (I and II) in vivo. The promoter for the putative cCXCR1 contains a variety of consensus transcription factor binding elements that can potentially be involved in the expression of this chicken receptor upon stimulation by stress-inducing agents. RT-PCR analysis was used to determine the pattern of expression of the larger isoform (I) of this receptor in a variety of tissues. This form of the receptor is expressed primarily in the organs of the gastrointestinal tract, tissues that are frequently exposed to stress-inducing agents, but not in the central nervous system, tissues that are protected from insult by the blood barrier. Using the same RT-PCR approach we show that stress-inducing agents, such as 'first-hand' and 'second-hand' cigarette smoke components, tumor promoters and thrombin, differentially stimulate the expression of the isoform I in primary fibroblasts. Thrombin is an enzyme that plays many important roles in thrombosis, angiogenesis and wound healing and exposure to both cigarette smokes and/or to tumor promoters can lead to tumorigenesis. Therefore, upregulation of chemokines and their receptors by stress-inducing agents can confer highly regulated modulation of cellular responses to traumatic and pathological situations.
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Affiliation(s)
- Q J Li
- Interdepartmental Graduate Program in Biochemistry, University of California, Riverside, CA 92521, USA
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28
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Grandaliano G, Monno R, Ranieri E, Gesualdo L, Schena FP, Martino C, Ursi M. Regenerative and proinflammatory effects of thrombin on human proximal tubular cells. J Am Soc Nephrol 2000; 11:1016-1025. [PMID: 10820165 DOI: 10.1681/asn.v1161016] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Interstitial fibrin deposition is a common histologic feature of tubulointerstitial diseases, which suggests that the coagulation system is activated. Thrombin, generated during the activation of the coagulation cascade, is a powerful activating factor for different cell types. Although proximal tubular cells are potential targets for this coagulation factor, no information is available on the effect of thrombin on these cells. Thus, the expression of protease-activated receptor-1 (PAR-1), the main thrombin receptor, was investigated in human proximal tubular cells (hPTC) in vivo and in vitro. A diffuse expression of PAR-1 was observed by immunohistochemistry along the basolateral membrane of PTC in normal human kidney. This observation was confirmed in vitro in cultured hPTC. Because tubular damage and monocyte infiltration are two hallmarks of tubulointerstitial injury, the effect of thrombin on DNA synthesis and monocyte chemotactic peptide-1 (MCP-1) gene and protein expression was evaluated in cultured hPTC. Thrombin induced a significant and dose-dependent increase in thymidine uptake and a striking upregulation of MCP-1 mRNA expression and protein release into the supernatant. Although PAR-1 is a G protein-coupled receptor, its activation in hPTC, as in other cell systems, resulted in a transient increase in cellular levels of tyrosine-phosphorylated proteins. An increased level of tyrosine-phosphorylated c-src suggested the activation of this cytoplasmic tyrosine kinase in response to thrombin and its potential role in thrombin-induced protein-tyrosine phosphorylation. Interestingly, thrombin-induced DNA synthesis and MCP-1 gene expression were completely blocked by genistein, a specific tyrosine kinase inhibitor, but not by its inactive analogue daidzein, demonstrating a central role for tyrosine kinase activation in the thrombin effects on hPTC. Moreover, the specific src inhibitor PP1 abolished the thrombin effect on DNA synthesis. In conclusion, thrombin might represent a powerful regenerative and proinflammatory stimulus for hPTC in acute and chronic tubulointerstitial diseases.
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Affiliation(s)
- Giuseppe Grandaliano
- Division of Nephrology/Department of Emergency and Transplantation, University of Bari, Italy
| | - Raffaella Monno
- Division of Nephrology/Department of Emergency and Transplantation, University of Bari, Italy
| | - Elena Ranieri
- Division of Nephrology/Department of Emergency and Transplantation, University of Bari, Italy
| | - Loreto Gesualdo
- Division of Nephrology/Department of Emergency and Transplantation, University of Bari, Italy
| | - Francesco P Schena
- Division of Nephrology/Department of Emergency and Transplantation, University of Bari, Italy
| | - Carmela Martino
- Division of Nephrology/Department of Emergency and Transplantation, University of Bari, Italy
| | - Michele Ursi
- Division of Nephrology/Department of Emergency and Transplantation, University of Bari, Italy
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29
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Martins-Green M, Bixby JL, Yamamoto T, Graf T, Sudol M. Tissue specific expression of Yrk kinase: implications for differentiation and inflammation. Int J Biochem Cell Biol 2000; 32:351-64. [PMID: 10716632 DOI: 10.1016/s1357-2725(99)00118-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The Src family of proto-oncogenes is a highly conserved group of non-receptor tyrosine kinases with very similar, but not identical, tissue distributions and functions. Yrk is a recently discovered new member of this family. Here we report the patterns of expression of this kinase in a variety of chicken tissues during development and after hatching, and experiments that correlate some of the observed patterns of expression with potential functions. The results show that the Yrk protein is primarily found in neuronal and epithelial cells and in monocyte/macrophages. In neuronal tissues of hatched chicks, Yrk is expressed in Purkinje cells, in the gigantocellularis of the brain-stem, and in retinal ganglion cells. In addition, staining for this kinase is also seen as thread-like and punctate patterns suggesting staining in neurites and growth cones. Epithelial cells express Yrk in the stomach during late developmental stages and after hatching but, in other epithelia such as in the peridermis, intestine and kidney, expression is high during development but low (skin) or undetectable (intestine and kidney) after hatching. These results suggest that Yrk may have several functional roles, specifically in cell migration and or differentiation during neuronal and epithelial cell development and in maintenance of the differentiated phenotype. In this study we also show that significant levels of Yrk are detected in monocytes of the blood and in tissue macrophages. Analysis of chicken hematopoietic cell lines confirmed the expression of Yrk in cells of monocyte/macrophage lineage and show for the first time in experimentally-induced inflammation that Yrk kinase activity is high during the period of monocyte infiltration, raising the possibility that this kinase plays a role in inflammation and/or response to injury.
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Affiliation(s)
- M Martins-Green
- Department of Cell Biology and Neurosciences, University of California, Riverside 92521, USA.
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30
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Prenzel N, Zwick E, Leserer M, Ullrich A. Tyrosine kinase signalling in breast cancer. Epidermal growth factor receptor: convergence point for signal integration and diversification. Breast Cancer Res 2000; 2:184-90. [PMID: 11250708 PMCID: PMC138773 DOI: 10.1186/bcr52] [Citation(s) in RCA: 115] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/1999] [Accepted: 02/21/2000] [Indexed: 12/16/2022] Open
Abstract
Cross-communication between different signalling systems is critical for the integration of multiple and changing environmental influences on individual cells. The epidermal growth factor receptor (EGFR) has been identified as a key element in the complex signalling network that is utilized by various classes of cell-surface receptors. This nonclassical mode of signalling system cross-talk, in distinction to receptor activation induced by cognate ligands, has been termed 'signal transactivation'. With the EGFR as the convergence point and distribution focus, this scenario may involve signals emitted by other members of the tyrosine kinase family, cytokine receptors, ion channels, G-protein-coupled receptors and integrins.
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Affiliation(s)
| | - Esther Zwick
- Max-Planck Institut für Biochemie, Martinsried, Germany
| | | | - Axel Ullrich
- Max-Planck Institut für Biochemie, Martinsried, Germany
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31
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Zwick E, Hackel PO, Prenzel N, Ullrich A. The EGF receptor as central transducer of heterologous signalling systems. Trends Pharmacol Sci 1999; 20:408-12. [PMID: 10577253 DOI: 10.1016/s0165-6147(99)01373-5] [Citation(s) in RCA: 279] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The cross-talk between heterologous signalling systems of the cell represents a new dimension of complexity in the molecular communication network that governs a great variety of physiological processes. In pathophysiologically transformed cells, key elements of this network could offer unique opportunities for pharmacological intervention. In this article, the current state of knowledge regarding the role of epidermal growth factor (EGF) in such a network is described and the recent advances made in the elucidation of the mechanism underlying EGF receptor transactivation are discussed.
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Affiliation(s)
- E Zwick
- Department of Molecular Biology, Max-Planck Institut für Biochemie, Martinsried, Germany.
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32
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Carpenter G. Employment of the epidermal growth factor receptor in growth factor-independent signaling pathways. J Cell Biol 1999; 146:697-702. [PMID: 10459005 PMCID: PMC2156131 DOI: 10.1083/jcb.146.4.697] [Citation(s) in RCA: 219] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/1999] [Accepted: 07/29/1999] [Indexed: 01/09/2023] Open
Affiliation(s)
- G Carpenter
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, USA.
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33
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Li Q, Vaingankar SM, Green HM, Martins-Green M. Activation of the 9E3/cCAF chemokine by phorbol esters occurs via multiple signal transduction pathways that converge to MEK1/ERK2 and activate the Elk1 transcription factor. J Biol Chem 1999; 274:15454-65. [PMID: 10336436 DOI: 10.1074/jbc.274.22.15454] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Using primary fibroblasts in culture, we have investigated the signal transduction mechanisms by which phorbol esters, a class of tumor promoters, activate the 9E3 gene and its chemokine product the chicken chemotactic and angiogenic factor. This gene is highly stimulated by phorbol 12,13-dibutyrate (PDBu) via three pathways: (i) a small contribution through protein kinase C (the commonly recognized pathway for these tumor promoters), (ii) a contribution involving tyrosine kinases, and (iii) a larger contribution via pathways that can be interrupted by dexamethasone. All three of these pathways converge into the mitogen-activated protein kinases, MEK1/ERK2. Using a luciferase reporter system, we show that although both the AP-1 and PDRIIkB (a NFkappaB-like factor in chickens) response elements are capable of activation in these normal cells, regions of the 9E3 promoter containing them are unresponsive to PDBu stimulation. In contrast, we show for the first time that activation by PDBu occurs through a segment of the promoter containing Elk1 response elements; deletion and mutation of these elements abrogates 9E3/chicken chemotactic and angiogenic factor expression. Electrophoretic mobility shift assays and functional studies using PathDetect systems show that stimulation of the cells by phorbol esters leads to activation of the Elk1 transcription factor, which binds to its element in the 9E3 promoter.
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Affiliation(s)
- Q Li
- Department of Biology, University of California, Riverside, California 92521, USA
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34
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Bianco C, Kannan S, De Santis M, Seno M, Tang CK, Martinez-Lacaci I, Kim N, Wallace-Jones B, Lippman ME, Ebert AD, Wechselberger C, Salomon DS. Cripto-1 indirectly stimulates the tyrosine phosphorylation of erb B-4 through a novel receptor. J Biol Chem 1999; 274:8624-9. [PMID: 10085099 DOI: 10.1074/jbc.274.13.8624] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cripto-1 (CR-1) is a recently discovered protein of the epidermal growth factor family that fails to directly bind to any of the four known erb B type 1 receptor tyrosine kinases. The present study demonstrates that CR-1 indirectly induces tyrosine phosphorylation of erb B-4 but not of the epidermal growth factor-related receptors erb B-2 and erb B-3 in different mouse and human mammary epithelial cell lines. In addition, down-regulation of erb B-4 in NMuMG mouse mammary epithelial cells and in T47D human breast cancer cells, using an anti-erb B-4 blocking antibody or a hammerhead ribozyme vector targeted to erb B-4 mRNA, impairs the ability of CR-1 to fully activate mitogen-activated protein kinase. Finally, chemical cross-linking of 125I-CR-1 to mouse and human mammary epithelial cell membranes results in the labeling of two specific bands with a molecular weight of 130 and 60 kDa, suggesting that the CR-1 receptor represents a novel receptor structurally unrelated to any of the known type I receptor tyrosine kinases. In conclusion, these data demonstrate that CR-1, upon binding to an unknown receptor, can enhance the tyrosine kinase activity of erb B-4 and that a functional erb B-4 receptor is required for CR-1-induced MAPK activation.
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Affiliation(s)
- C Bianco
- Tumor Growth Factor Section, Laboratory of Tumor Immunology and Biology, NCI, National Institutes of Health, Bethesda, Maryland 20892, USA
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