The Experts below are selected from a list of 1767 Experts worldwide ranked by ideXlab platform
Carl P. Blobel - One of the best experts on this subject based on the ideXlab platform.
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ADAM17/TACE inhibits Schwann cell myelination
Nature Neuroscience, 2011Co-Authors: Rosa La Marca, Carl P. Blobel, Keisuke Horiuchi, Federica Cerri, Angela Bachi, Maria Laura Feltri, Lawrence Wrabetz, Angelo Quattrini, James L. Salzer, Carla TaveggiaAbstract:TACE, the tumor necrosis factor alpha-converting enzyme, is a proteolytic Sheddase responsible for the cleavage of several membrane-bound molecules. We report that TACE cleaves NRG1 type III in the EGF domain, likely inactivating it, as assessed by deficient activation of PI-3 kinase pathway, thereby negatively regulating PNS myelination. Lentiviral mediated knockdown of TACE in vitro in dorsal root ganglia neurons accelerates the onset of myelination and results in hypermyelination. In agreement, conditional knockout mice lacking TACE in motor neurons are significantly hypermyelinated and small caliber fibers aberrantly myelinated. Further, reduced TACE activity rescues NRG1 type III hypomyelination in vivo. We also show that the inhibitory effect of TACE is neuron autonomous as Schwann cells lacking TACE elaborate myelin of normal myelin thickness. Thus, TACE is a novel modulator of Neuregulin 1 type III activity and is a significantly negative regulator of myelination in the PNS.
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stimulation of platelet derived growth factor receptor β pdgfrβ activates adam17 and promotes metalloproteinase dependent cross talk between the pdgfrβ and epidermal growth factor receptor egfr signaling pathways
Journal of Biological Chemistry, 2010Co-Authors: Karen Mendelson, Carl P. Blobel, Steven Swendeman, Paul SaftigAbstract:Binding of the platelet-derived growth factor (PDGF)-B to its receptor PDGFRβ promotes proliferation, migration, and recruitment of pericytes and smooth muscle cells to endothelial cells, serving to stabilize developing blood vessels. The main goals of this study were to determine whether the extracellular domain of the PDGFRβ can be proteolytically released from cell membranes and, if so, to identify the responsible Sheddase and determine whether activation of the PDGFRβ stimulates its shedding and potentially that of other membrane proteins. We found that the PDGFRβ is shed from cells by a metalloproteinase and used loss-of-function experiments to identify ADAM10 as the Sheddase responsible for constitutive and ionomycin-stimulated processing of the PDGFRβ. Moreover, we showed that ligand-dependent activation of the PDGFRβ does not trigger its own shedding by ADAM10, but instead it stimulates ADAM17 and shedding of substrates of ADAM17, including tumor necrosis factor α and transforming growth factor α. Finally, we demonstrated that treatment of mouse embryonic fibroblasts with PDGF-B triggers a metalloproteinase-dependent cross-talk between the PDGFRβ and the epidermal growth factor receptor (EGFR)/ERK1/2 signaling axis that is also critical for PDGF-B-stimulated cell migration, most likely via ADAM17-dependent release and activation of ligands of the EGFR. This study identifies the principal Sheddase for the PDGFRβ and provides new insights into the mechanism of PDGFRβ-dependent signal transduction and cross-talk with the EGFR.
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Shedding of Collagen XVII/BP180 in Skin Depends on Both ADAM10 and ADAM9
The Journal of biological chemistry, 2009Co-Authors: Claus-werner Franzke, Leena Bruckner-tuderman, Carl P. BlobelAbstract:Collagen XVII is a transmembrane collagen and the major autoantigen of the autoimmune skin blistering disease bullous pemphigoid. Collagen XVII is proteolytically released from the membrane, and the pathogenic epitope harbors the cleavage site for its ectodomain shedding, suggesting that proteolysis has an important role in regulating the function of collagen XVII in skin homeostasis. Previous studies identified ADAMs 9, 10, and 17 as candidate collagen XVII Sheddases and suggested that ADAM17 is a major Sheddase. Here we show that ADAM17 only indirectly affects collagen XVII shedding and that ADAMs 9 and 10 are the most prominent collagen XVII Sheddases in primary keratinocytes because (a) collagen XVII shedding was not stimulated by phorbol esters, known activators of ADAM17, (b) constitutive and calcium influx-stimulated shedding was sensitive to the ADAM10-selective inhibitor GI254023X and was strongly reduced in Adam10(-/-) cells, (c) there was a 55% decrease in constitutive collagen XVII ectodomain shedding from Adam9(-/-) keratinocytes, and (d) H(2)O(2) enhanced ADAM9 expression and stimulated collagen XVII shedding in skin and keratinocytes of wild type mice but not of Adam9(-/-) mice. We conclude that ADAM9 and ADAM10 can both contribute to collagen XVII shedding in skin with an enhanced relative contribution of ADAM9 in the presence of reactive oxygen species. These results provide critical new insights into the identity and regulation of the major Sheddases for collagen XVII in keratinocytes and skin and have implications for the treatment of blistering diseases of the skin.
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ADAMs 10 and 17 Represent Differentially Regulated Components of a General Shedding Machinery for Membrane Proteins Such as Transforming Growth Factor α, L-Selectin, and Tumor Necrosis Factor α
Molecular biology of the cell, 2009Co-Authors: Sylvain Le Gall, Keisuke Horiuchi, Karina Reiss, Pierre Bobe, Xiao Da Niu, Daniel Lundell, David R. Gibb, Daniel Conrad, P. Saftig, Carl P. BlobelAbstract:Protein ectodomain shedding is a critical regulator of many membrane proteins, including epidermal growth factor receptor-ligands and tumor necrosis factor (TNF)-alpha, providing a strong incentive to define the responsible Sheddases. Previous studies identified ADAM17 as principal Sheddase for transforming growth factor (TGF)-alpha and heparin-binding epidermal growth factor, but Ca++ influx activated an additional Sheddase for these epidermal growth factor receptor ligands in Adam17-/- cells. Here, we show that Ca++ influx and stimulation of the P2X7R signaling pathway activate ADAM10 as Sheddase of many ADAM17 substrates in Adam17-/- fibroblasts and primary B cells. Importantly, although ADAM10 can shed all substrates of ADAM17 tested here in Adam17-/- cells, acute treatment of wild-type cells with a highly selective ADAM17 inhibitor (SP26) showed that ADAM17 is nevertheless the principal Sheddase when both ADAMs 10 and 17 are present. However, chronic treatment of wild-type cells with SP26 promoted processing of ADAM17 substrates by ADAM10, thus generating conditions such as in Adam17-/- cells. These results have general implications for understanding the substrate selectivity of two major cellular Sheddases, ADAMs 10 and 17.
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Cutting Edge: TNF-α-Converting Enzyme (TACE/ADAM17) Inactivation in Mouse Myeloid Cells Prevents Lethality from Endotoxin Shock
Journal of immunology (Baltimore Md. : 1950), 2007Co-Authors: Keisuke Horiuchi, Yoshiaki Toyama, Tokuhiro Kimura, Takeshi Miyamoto, Hironari Takaishi, Yasunori Okada, Carl P. BlobelAbstract:TNF-α, a potent proinflammatory cytokine, is synthesized as a membrane-anchored precursor and proteolytically released from cells. Soluble TNF is the primary mediator of pathologies such as rheumatoid arthritis, Crohn’s disease, and endotoxin shock. The TNF-α converting enzyme (TACE), a disintegrin and metalloprotease 17 (ADAM17), has emerged as the best candidate TNF Sheddase, but other proteinases can also release TNF. Because TACE-deficient mice die shortly after birth, we generated conditional TACE-deficient mice to address whether TACE is the relevant Sheddase for TNF in adult mice. In this study, we report that TACE inactivation in myeloid cells or temporal inactivation at 6 wk offers strong protection from endotoxin shock lethality in mice by preventing increased TNF serum levels. These findings corroborate that TACE is the major endotoxin-stimulated TNF Sheddase in mouse myeloid cells in vivo, thereby further validating TACE as a principal target for the treatment of TNF-dependent pathologies.
Keisuke Horiuchi - One of the best experts on this subject based on the ideXlab platform.
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ADAM17/TACE inhibits Schwann cell myelination
Nature Neuroscience, 2011Co-Authors: Rosa La Marca, Carl P. Blobel, Keisuke Horiuchi, Federica Cerri, Angela Bachi, Maria Laura Feltri, Lawrence Wrabetz, Angelo Quattrini, James L. Salzer, Carla TaveggiaAbstract:TACE, the tumor necrosis factor alpha-converting enzyme, is a proteolytic Sheddase responsible for the cleavage of several membrane-bound molecules. We report that TACE cleaves NRG1 type III in the EGF domain, likely inactivating it, as assessed by deficient activation of PI-3 kinase pathway, thereby negatively regulating PNS myelination. Lentiviral mediated knockdown of TACE in vitro in dorsal root ganglia neurons accelerates the onset of myelination and results in hypermyelination. In agreement, conditional knockout mice lacking TACE in motor neurons are significantly hypermyelinated and small caliber fibers aberrantly myelinated. Further, reduced TACE activity rescues NRG1 type III hypomyelination in vivo. We also show that the inhibitory effect of TACE is neuron autonomous as Schwann cells lacking TACE elaborate myelin of normal myelin thickness. Thus, TACE is a novel modulator of Neuregulin 1 type III activity and is a significantly negative regulator of myelination in the PNS.
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Leukocyte ADAM17 regulates acute pulmonary inflammation.
PloS one, 2011Co-Authors: Patrick G. Arndt, Keisuke Horiuchi, Brian Strahan, Yue Wang, Chunmei Long, Bruce WalcheckAbstract:The transmembrane protease ADAM17 regulates the release and density of various leukocyte cell surface proteins that modulate inflammation, including L-selectin, TNF-α, and IL-6R. At this time, its in vivo substrates and role in pulmonary inflammation have not been directly examined. Using conditional ADAM17 knock-out mice, we investigated leukocyte ADAM17 in acute lung inflammation. Alveolar TNF-α levels were significantly reduced (>95%) in ADAM17-null mice following LPS administration, as was the shedding of L-selectin, a neutrophil-expressed adhesion molecule. Alveolar IL-6R levels, however, were reduced by only ≈25% in ADAM17-null mice, indicating that ADAM17 is not its primary Sheddase in our model. Neutrophil infiltration into the alveolar compartment is a key event in the pathophysiology of acute airway inflammation. Following LPS inhalation, alveolar neutrophil levels and lung inflammation in ADAM17-null mice were overall reduced when compared to control mice. Interestingly, however, neutrophil recruitment to the alveolar compartment occurred earlier in ADAM17-null mice after exposure to LPS. This decrease in alveolar neutrophil recruitment in ADAM17-null mice was accompanied by significantly diminished alveolar levels of the neutrophil-tropic chemokines CXCL1 and CXCL5. Altogether, our study suggests that leukocyte ADAM17 promotes inflammation in the lung, and thus this Sheddase may be a potential target in the design of pharmacologic therapies for acute lung injury.
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ADAMs 10 and 17 Represent Differentially Regulated Components of a General Shedding Machinery for Membrane Proteins Such as Transforming Growth Factor α, L-Selectin, and Tumor Necrosis Factor α
Molecular biology of the cell, 2009Co-Authors: Sylvain Le Gall, Keisuke Horiuchi, Karina Reiss, Pierre Bobe, Xiao Da Niu, Daniel Lundell, David R. Gibb, Daniel Conrad, P. Saftig, Carl P. BlobelAbstract:Protein ectodomain shedding is a critical regulator of many membrane proteins, including epidermal growth factor receptor-ligands and tumor necrosis factor (TNF)-alpha, providing a strong incentive to define the responsible Sheddases. Previous studies identified ADAM17 as principal Sheddase for transforming growth factor (TGF)-alpha and heparin-binding epidermal growth factor, but Ca++ influx activated an additional Sheddase for these epidermal growth factor receptor ligands in Adam17-/- cells. Here, we show that Ca++ influx and stimulation of the P2X7R signaling pathway activate ADAM10 as Sheddase of many ADAM17 substrates in Adam17-/- fibroblasts and primary B cells. Importantly, although ADAM10 can shed all substrates of ADAM17 tested here in Adam17-/- cells, acute treatment of wild-type cells with a highly selective ADAM17 inhibitor (SP26) showed that ADAM17 is nevertheless the principal Sheddase when both ADAMs 10 and 17 are present. However, chronic treatment of wild-type cells with SP26 promoted processing of ADAM17 substrates by ADAM10, thus generating conditions such as in Adam17-/- cells. These results have general implications for understanding the substrate selectivity of two major cellular Sheddases, ADAMs 10 and 17.
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Cutting Edge: TNF-α-Converting Enzyme (TACE/ADAM17) Inactivation in Mouse Myeloid Cells Prevents Lethality from Endotoxin Shock
Journal of immunology (Baltimore Md. : 1950), 2007Co-Authors: Keisuke Horiuchi, Yoshiaki Toyama, Tokuhiro Kimura, Takeshi Miyamoto, Hironari Takaishi, Yasunori Okada, Carl P. BlobelAbstract:TNF-α, a potent proinflammatory cytokine, is synthesized as a membrane-anchored precursor and proteolytically released from cells. Soluble TNF is the primary mediator of pathologies such as rheumatoid arthritis, Crohn’s disease, and endotoxin shock. The TNF-α converting enzyme (TACE), a disintegrin and metalloprotease 17 (ADAM17), has emerged as the best candidate TNF Sheddase, but other proteinases can also release TNF. Because TACE-deficient mice die shortly after birth, we generated conditional TACE-deficient mice to address whether TACE is the relevant Sheddase for TNF in adult mice. In this study, we report that TACE inactivation in myeloid cells or temporal inactivation at 6 wk offers strong protection from endotoxin shock lethality in mice by preventing increased TNF serum levels. These findings corroborate that TACE is the major endotoxin-stimulated TNF Sheddase in mouse myeloid cells in vivo, thereby further validating TACE as a principal target for the treatment of TNF-dependent pathologies.
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Different ADAMs have distinct influences on Kit ligand processing: phorbol-ester-stimulated ectodomain shedding of Kitl1 by ADAM17 is reduced by ADAM19.
Journal of cell science, 2007Co-Authors: Nobuko Kawaguchi, Keisuke Horiuchi, Yoshiaki Toyama, J David Becherer, Peter Besmer, Carl P. BlobelAbstract:Kit ligand (Kitl), the ligand for the Kit receptor tyrosine kinase, plays important roles in hematopoiesis, gametogenesis and melanogenesis. Kitl is synthesized as a membrane-anchored precursor that can be processed to produce the soluble growth factor. Here, we evaluated the role of ADAM (a disintegrin and metalloprotease) metalloproteases in ectodomain shedding of Kitl. We found that both ADAM17 and ADAM19 affect Kitl1 shedding, albeit in different ways. Overexpression of ADAM19 resulted in decreased levels of Endo-H-resistant mature Kitl1, thereby reducing the amount of Kitl that is shed from cells following stimulation with phorbol esters. ADAM17 was identified as the major phorbol-ester-stimulated Sheddase of Kitl1, whereas ADAMs 8, 9, 10, 12 and 15 were not required for this process. ADAM17 also emerged as the major constitutive and phorbol-ester-stimulated Sheddase of Kitl2 in mouse embryonic fibroblasts. Mutagenesis of the juxtamembrane domain of Kitl2 showed no stringent sequence requirement for cleavage by ADAM17, although two nonadjacent stretches of four amino acid residues were identified that are required for Kitl2 shedding. Taken together, this study identifies a novel Sheddase, ADAM17, for Kitl1 and Kitl2, and demonstrates that ADAM19 can reduce ADAM17-dependent phorbol-ester-stimulated Kitl1 ectodomain shedding.
Peggy Scherle - One of the best experts on this subject based on the ideXlab platform.
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Discovery of novel selective HER-2 Sheddase inhibitors through optimization of P1 moiety.
Bioorganic & medicinal chemistry letters, 2009Co-Authors: Eric Shi, Peggy Scherle, David M. Burns, Maryanne Covington, Maxwell Pan, Steve Friedman, Brian W. Metcalf, Wenqing YaoAbstract:A novel series of carbamates was discovered as potent and selective HER-2 Sheddase inhibitors. Significant enhancement in potency and selectivity was achieved through attenuating the P1 moiety, which was conventionally believed to be exposed to solvent.
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synergistic inhibition with a dual epidermal growth factor receptor her 2 neu tyrosine kinase inhibitor and a disintegrin and metalloprotease inhibitor
Cancer Research, 2008Co-Authors: Lois Witters, Peggy Scherle, Steven Friedman, Jordan S Fridman, Eian Caulder, Robert C Newton, Allan LiptonAbstract:The ErbB family of receptors is overexpressed in numerous human tumors. Overexpression correlates with poor prognosis and resistance to therapy. Use of ErbB-specific antibodies to the receptors (Herceptin or Erbitux) or ErbB-specific small-molecule inhibitors of the receptor tyrosine kinase activity (Iressa or Tarceva) has shown clinical efficacy in several solid tumors. An alternative method of affecting ErbB-initiated tumor growth and survival is to block Sheddase activity. Sheddase activity is responsible for cleavage of multiple ErbB ligands and receptors, a necessary step in availability of the soluble, active form of the ligand and a constitutively activated ligand-independent receptor. This Sheddase activity is attributed to the ADAM (a disintegrin and metalloprotease) family of proteins. ADAM 10 is the main Sheddase of epidermal growth factor (EGF) and HER-2/neu cleavage, whereas ADAM17 is required for cleavage of additional EGF receptor (EGFR) ligands (transforming growth factor-α, amphiregulin, heregulin, heparin binding EGF-like ligand). This study has shown that addition of INCB3619, a potent inhibitor of ADAM10 and ADAM17, reduces in vitro HER-2/neu and amphiregulin shedding, confirming that it interferes with both HER-2/neu and EGFR ligand cleavage. Combining INCB3619 with a lapatinib-like dual inhibitor of EGFR and HER-2/neu kinases resulted in synergistic growth inhibition in MCF-7 and HER-2/neu–transfected MCF-7 human breast cancer cells. Combining the INCB7839 second-generation Sheddase inhibitor with lapatinib prevented the growth of HER-2/neu–positive BT474-SC1 human breast cancer xenografts in vivo . These results suggest that there may be an additional clinical benefit of combining agents that target the ErbB pathways at multiple points. [Cancer Res 2008;68(17):7083–9]
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Synergistic inhibition with a dual epidermal growth factor receptor/HER-2/neu tyrosine kinase inhibitor and a disintegrin and metalloprotease inhibitor.
Cancer research, 2008Co-Authors: Lois Witters, Peggy Scherle, Steven Friedman, Jordan S Fridman, Eian Caulder, Robert C Newton, Allan LiptonAbstract:The ErbB family of receptors is overexpressed in numerous human tumors. Overexpression correlates with poor prognosis and resistance to therapy. Use of ErbB-specific antibodies to the receptors (Herceptin or Erbitux) or ErbB-specific small-molecule inhibitors of the receptor tyrosine kinase activity (Iressa or Tarceva) has shown clinical efficacy in several solid tumors. An alternative method of affecting ErbB-initiated tumor growth and survival is to block Sheddase activity. Sheddase activity is responsible for cleavage of multiple ErbB ligands and receptors, a necessary step in availability of the soluble, active form of the ligand and a constitutively activated ligand-independent receptor. This Sheddase activity is attributed to the ADAM (a disintegrin and metalloprotease) family of proteins. ADAM 10 is the main Sheddase of epidermal growth factor (EGF) and HER-2/neu cleavage, whereas ADAM17 is required for cleavage of additional EGF receptor (EGFR) ligands (transforming growth factor-alpha, amphiregulin, heregulin, heparin binding EGF-like ligand). This study has shown that addition of INCB3619, a potent inhibitor of ADAM10 and ADAM17, reduces in vitro HER-2/neu and amphiregulin shedding, confirming that it interferes with both HER-2/neu and EGFR ligand cleavage. Combining INCB3619 with a lapatinib-like dual inhibitor of EGFR and HER-2/neu kinases resulted in synergistic growth inhibition in MCF-7 and HER-2/neu-transfected MCF-7 human breast cancer cells. Combining the INCB7839 second-generation Sheddase inhibitor with lapatinib prevented the growth of HER-2/neu-positive BT474-SC1 human breast cancer xenografts in vivo. These results suggest that there may be an additional clinical benefit of combining agents that target the ErbB pathways at multiple points.
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Conversion of an MMP-potent scaffold to an MMP-selective HER-2 Sheddase inhibitor via scaffold hybridization and subtle P1' permutations.
Bioorganic & medicinal chemistry letters, 2007Co-Authors: David M. Burns, Peggy Scherle, Xiangdong Liu, Gengjie Yang, Cindy Marando, Mayanne B. Covington, Max Pan, Sharon TurnerAbstract:A series of beta-sulfonamide piperidine hydroxamates were prepared and shown to be potent inhibitors of the human epidermal growth factor receptor-2 (HER-2) Sheddase with excellent selectivity against MMP-1, -2, -3, and -9. This was achieved by exploiting subtle differences within the otherwise highly conserved S(1)(') binding pocket of the active sites within the metalloprotease family. In addition, it was discovered that the introduction of polarity to the P(1) and P(1)(') groups reduced the projected human clearance.
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ADAM proteases, ErbB pathways and cancer.
Expert opinion on investigational drugs, 2005Co-Authors: Bin-bing S. Zhou, Jordan S Fridman, Robert C Newton, Steve Friedman, Xiangdong Liu, Peggy ScherleAbstract:A disintegrin and metalloproteases (ADAMs) are zinc-dependent trans-membrane metalloproteases that shed the extracellular domains of membrane-bound growth factors, cytokines and receptors. Key functions of ADAMs have emerged in ErbB signalling pathways as being Sheddases for multiple ErbB ligands. As the ErbB pathway is a validated target for anti-cancer drugs, the upstream activators of ErbB ligands, their Sheddases, now enter the spotlight as new drug targets in the ErbB pathway. ADAMs are involved not only in tumour cell proliferation but also in angiogenesis and metastasis. Therefore, strategies targeting ADAMs might be an important complement to existing anti-ErbB approaches.
Allan Lipton - One of the best experts on this subject based on the ideXlab platform.
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synergistic inhibition with a dual epidermal growth factor receptor her 2 neu tyrosine kinase inhibitor and a disintegrin and metalloprotease inhibitor
Cancer Research, 2008Co-Authors: Lois Witters, Peggy Scherle, Steven Friedman, Jordan S Fridman, Eian Caulder, Robert C Newton, Allan LiptonAbstract:The ErbB family of receptors is overexpressed in numerous human tumors. Overexpression correlates with poor prognosis and resistance to therapy. Use of ErbB-specific antibodies to the receptors (Herceptin or Erbitux) or ErbB-specific small-molecule inhibitors of the receptor tyrosine kinase activity (Iressa or Tarceva) has shown clinical efficacy in several solid tumors. An alternative method of affecting ErbB-initiated tumor growth and survival is to block Sheddase activity. Sheddase activity is responsible for cleavage of multiple ErbB ligands and receptors, a necessary step in availability of the soluble, active form of the ligand and a constitutively activated ligand-independent receptor. This Sheddase activity is attributed to the ADAM (a disintegrin and metalloprotease) family of proteins. ADAM 10 is the main Sheddase of epidermal growth factor (EGF) and HER-2/neu cleavage, whereas ADAM17 is required for cleavage of additional EGF receptor (EGFR) ligands (transforming growth factor-α, amphiregulin, heregulin, heparin binding EGF-like ligand). This study has shown that addition of INCB3619, a potent inhibitor of ADAM10 and ADAM17, reduces in vitro HER-2/neu and amphiregulin shedding, confirming that it interferes with both HER-2/neu and EGFR ligand cleavage. Combining INCB3619 with a lapatinib-like dual inhibitor of EGFR and HER-2/neu kinases resulted in synergistic growth inhibition in MCF-7 and HER-2/neu–transfected MCF-7 human breast cancer cells. Combining the INCB7839 second-generation Sheddase inhibitor with lapatinib prevented the growth of HER-2/neu–positive BT474-SC1 human breast cancer xenografts in vivo . These results suggest that there may be an additional clinical benefit of combining agents that target the ErbB pathways at multiple points. [Cancer Res 2008;68(17):7083–9]
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Synergistic inhibition with a dual epidermal growth factor receptor/HER-2/neu tyrosine kinase inhibitor and a disintegrin and metalloprotease inhibitor.
Cancer research, 2008Co-Authors: Lois Witters, Peggy Scherle, Steven Friedman, Jordan S Fridman, Eian Caulder, Robert C Newton, Allan LiptonAbstract:The ErbB family of receptors is overexpressed in numerous human tumors. Overexpression correlates with poor prognosis and resistance to therapy. Use of ErbB-specific antibodies to the receptors (Herceptin or Erbitux) or ErbB-specific small-molecule inhibitors of the receptor tyrosine kinase activity (Iressa or Tarceva) has shown clinical efficacy in several solid tumors. An alternative method of affecting ErbB-initiated tumor growth and survival is to block Sheddase activity. Sheddase activity is responsible for cleavage of multiple ErbB ligands and receptors, a necessary step in availability of the soluble, active form of the ligand and a constitutively activated ligand-independent receptor. This Sheddase activity is attributed to the ADAM (a disintegrin and metalloprotease) family of proteins. ADAM 10 is the main Sheddase of epidermal growth factor (EGF) and HER-2/neu cleavage, whereas ADAM17 is required for cleavage of additional EGF receptor (EGFR) ligands (transforming growth factor-alpha, amphiregulin, heregulin, heparin binding EGF-like ligand). This study has shown that addition of INCB3619, a potent inhibitor of ADAM10 and ADAM17, reduces in vitro HER-2/neu and amphiregulin shedding, confirming that it interferes with both HER-2/neu and EGFR ligand cleavage. Combining INCB3619 with a lapatinib-like dual inhibitor of EGFR and HER-2/neu kinases resulted in synergistic growth inhibition in MCF-7 and HER-2/neu-transfected MCF-7 human breast cancer cells. Combining the INCB7839 second-generation Sheddase inhibitor with lapatinib prevented the growth of HER-2/neu-positive BT474-SC1 human breast cancer xenografts in vivo. These results suggest that there may be an additional clinical benefit of combining agents that target the ErbB pathways at multiple points.
Karina Reiss - One of the best experts on this subject based on the ideXlab platform.
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the plasma membrane penultimate regulator of adam Sheddase function
Biochimica et Biophysica Acta, 2017Co-Authors: Karina Reiss, Sucharit BhakdiAbstract:Abstract Background ADAM10 and ADAM17 are the best characterized members of the ADAM (A Disintegrin and Metalloproteinase) – family of transmembrane proteases. Both are involved diverse physiological and pathophysiological processes. ADAMs are known to be regulated by posttranslational mechanisms. However, emerging evidence indicates that the plasma membrane with its unique dynamic properties may additionally play an important role in controlling Sheddase function. Scope of review Membrane events that could contribute to regulation of ADAM-function are summarized. Major conclusions Surface expression of peptidolytic activity should be differentiated from ADAM-Sheddase function since the latter additionally requires that the protease finds its substrate in the lipid bilayer. We propose that this is achieved through horizontal and vertical reorganization of membrane nanoarchitecture coordinately occurring at the sites of Sheddase activation. Reshuffling of nanodomains thereby guides traffic of enzyme and substrate to each other. For ADAM17 phosphatidylserine exposure is required to then induce its shedding function. General significance The novel concept that physicochemical properties of the lipid bilayer govern the action of ADAM-proteases may be extendable to other functional proteins that act at the cell surface. This article is part of a Special Issue entitled: Proteolysis as a Regulatory Event in Pathophysiology edited by Stefan Rose-John.
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The plasma membrane: Penultimate regulator of ADAM Sheddase function.
Biochimica et biophysica acta. Molecular cell research, 2017Co-Authors: Karina Reiss, Sucharit BhakdiAbstract:ADAM10 and ADAM17 are the best characterized members of the ADAM (A Disintegrin and Metalloproteinase) - family of transmembrane proteases. Both are involved diverse physiological and pathophysiological processes. ADAMs are known to be regulated by posttranslational mechanisms. However, emerging evidence indicates that the plasma membrane with its unique dynamic properties may additionally play an important role in controlling Sheddase function. Membrane events that could contribute to regulation of ADAM-function are summarized. Surface expression of peptidolytic activity should be differentiated from ADAM-Sheddase function since the latter additionally requires that the protease finds its substrate in the lipid bilayer. We propose that this is achieved through horizontal and vertical reorganization of membrane nanoarchitecture coordinately occurring at the sites of Sheddase activation. Reshuffling of nanodomains thereby guides traffic of enzyme and substrate to each other. For ADAM17 phosphatidylserine exposure is required to then induce its shedding function. The novel concept that physicochemical properties of the lipid bilayer govern the action of ADAM-proteases may be extendable to other functional proteins that act at the cell surface. This article is part of a Special Issue entitled: Proteolysis as a Regulatory Event in Pathophysiology edited by Stefan Rose-John. Copyright © 2017. Published by Elsevier B.V.
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how membrane asymmetry regulates adam17 Sheddase function
Cell Cycle, 2016Co-Authors: Anselm Sommer, Sucharit Bhakdi, Karina ReissAbstract:Asymmetrical distribution of lipids in the cell membrane is a fundamental feature of all eukaryotic cells. The most important negatively charged phospholipids phosphatidylserine (PS) and phosphatidylinositol species reside almost exclusively in the cytoplasmic leaflet, where they serve as essential co-factors for many membrane-bound enzymes including protein kinase C, phosphatase PTEN, tyrosine kinase c-Src, and MARCKS.1 Clusters of basic amino acid residues draw the proteins via electrostatic interactions to the lipid, enabling them to exert their function at the cytosolic membrane face.
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ADAMs 10 and 17 Represent Differentially Regulated Components of a General Shedding Machinery for Membrane Proteins Such as Transforming Growth Factor α, L-Selectin, and Tumor Necrosis Factor α
Molecular biology of the cell, 2009Co-Authors: Sylvain Le Gall, Keisuke Horiuchi, Karina Reiss, Pierre Bobe, Xiao Da Niu, Daniel Lundell, David R. Gibb, Daniel Conrad, P. Saftig, Carl P. BlobelAbstract:Protein ectodomain shedding is a critical regulator of many membrane proteins, including epidermal growth factor receptor-ligands and tumor necrosis factor (TNF)-alpha, providing a strong incentive to define the responsible Sheddases. Previous studies identified ADAM17 as principal Sheddase for transforming growth factor (TGF)-alpha and heparin-binding epidermal growth factor, but Ca++ influx activated an additional Sheddase for these epidermal growth factor receptor ligands in Adam17-/- cells. Here, we show that Ca++ influx and stimulation of the P2X7R signaling pathway activate ADAM10 as Sheddase of many ADAM17 substrates in Adam17-/- fibroblasts and primary B cells. Importantly, although ADAM10 can shed all substrates of ADAM17 tested here in Adam17-/- cells, acute treatment of wild-type cells with a highly selective ADAM17 inhibitor (SP26) showed that ADAM17 is nevertheless the principal Sheddase when both ADAMs 10 and 17 are present. However, chronic treatment of wild-type cells with SP26 promoted processing of ADAM17 substrates by ADAM10, thus generating conditions such as in Adam17-/- cells. These results have general implications for understanding the substrate selectivity of two major cellular Sheddases, ADAMs 10 and 17.
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substrate selectivity of epidermal growth factor receptor ligand Sheddases and their regulation by phorbol esters and calcium influx
Molecular Biology of the Cell, 2006Co-Authors: Gillian Murphy, Dieter Hartmann, Keisuke Horiuchi, Karina Reiss, Sylvain Le Gall, Marc Schulte, Takafumi Yamaguchi, Yoshiaki Toyama, Paul SaftigAbstract:Signaling via the epidermal growth factor receptor (EGFR), which has critical roles in development and diseases such as cancer, is regulated by proteolytic shedding of its membrane-tethered ligands. Sheddases for EGFR-ligands are therefore key signaling switches in the EGFR pathway. Here, we determined which ADAMs (a disintegrin and metalloprotease) can shed various EGFR-ligands, and we analyzed the regulation of EGFR-ligand shedding by two commonly used stimuli, phorbol esters and calcium influx. Phorbol esters predominantly activate ADAM17, thereby triggering a burst of shedding of EGFR-ligands from a late secretory pathway compartment. Calcium influx stimulates ADAM10, requiring its cytoplasmic domain. However, calcium influx-stimulated shedding of transforming growth factor alpha and amphiregulin does not require ADAM17, even though ADAM17 is essential for phorbol ester-stimulated shedding of these EGFR-ligands. This study provides new insight into the machinery responsible for EGFR-ligand release and thus EGFR signaling and demonstrates that dysregulated EGFR-ligand shedding may be caused by increased expression of constitutively active Sheddases or activation of different Sheddases by distinct stimuli.
