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Boris Turk - One of the best experts on this subject based on the ideXlab platform.
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cysteine Cathepsins in extracellular matrix remodeling extracellular matrix degradation and beyond
Matrix Biology, 2018Co-Authors: Matej Vizovisek, Boris Turk, Marko FonovicAbstract:Cysteine Cathepsins have been for a long time considered to execute mainly nonspecific bulk proteolysis in the endolysosomal system. However, this view has been changing profoundly over the last decade as Cathepsins were found in the cytoplasm, nucleus and in the extracellular milieu. Cathepsins are currently gaining increased attention largely because of their extracellular roles associated with disease development and progression. While kept under tight control under physiological conditions, their dysregulated and elevated activity in the extracellular milieu are distinctive hallmarks of numerous diseases such as various cancers, inflammatory disorders, rheumatoid arthritis, bone disorders and heart diseases. In this review, we discuss cysteine Cathepsins with a major focus on their extracellular roles and extracellular proteolytic targets beyond degradation of the extracellular matrix. We further highlight the perspectives of Cathepsin research and novel avenues in Cathepsin-based diagnostic and therapeutic applications.
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the future of cysteine Cathepsins in disease management
Trends in Pharmacological Sciences, 2017Co-Authors: Lovro Kramer, Dušan Turk, Boris TurkAbstract:Since the discovery of the key role of Cathepsin K in bone resorption, cysteine Cathepsins have been investigated by pharmaceutical companies as drug targets. The first clinical results from targeting Cathepsins by activity-based probes and substrates are paving the way for the next generation of molecular diagnostic imaging, whereas the majority of antibody–drug conjugates currently in clinical trials depend on activation by Cathepsins. Finally, Cathepsins have emerged as suitable vehicles for targeted drug delivery. It is therefore timely to review the future of Cathepsins in drug discovery. We focus here on inflammation-associated diseases because dysregulation of the immune system accompanied by elevated Cathepsin activity is a common feature of these conditions.
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Non-invasive in vivo imaging of tumour-associated Cathepsin B by a highly selective inhibitory DARPin.
Theranostics, 2017Co-Authors: Lovro Kramer, Markus A. Seeger, Markus G. Grütter, Miha Renko, Janja Završnik, Dušan Turk, Olga Vasiljeva, Vito Turk, Boris TurkAbstract:Cysteine Cathepsins often contribute to cancer progression due to their overexpression in the tumour microenvironment and therefore present attractive targets for non-invasive diagnostic imaging. However, the development of highly selective and versatile small molecule probes for Cathepsins has been challenging. Here, we targeted tumour-associated Cathepsin B using designed ankyrin repeat proteins (DARPins). The selective DARPin 8h6 inhibited Cathepsin B with picomolar affinity (Ki = 35 pM) by binding to a site with low structural conservation in Cathepsins, as revealed by the X-ray structure of the complex. DARPin 8h6 blocked Cathepsin B activity in tumours ex vivo and was successfully applied in in vivo optical imaging in two mouse breast cancer models, in which Cathepsin B was bound to the cell membrane or secreted to the extracellular milieu by tumour and stromal cells. Our approach validates Cathepsin B as a promising diagnostic and theranostic target in cancer and other inflammation-associated diseases.
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Cathepsin X binds to cell surface heparan sulfate proteoglycans.
Archives of biochemistry and biophysics, 2005Co-Authors: Fabio D. Nascimento, Adriana K Carmona, Luiz Juliano, Helena B. Nader, Boris Turk, Claudia C.a. Rizzi, Iseli L. Nantes, Ivica Stefe, Ivarne L.s. TersariolAbstract:Glycosaminoglycans have been shown to be important regulators of activity of several papain-like Cathepsins. Binding of glycosaminoglycans to Cathepsins thus directly affects catalytic activity, stability or the rate of autocatalytic activation of Cathepsins. The interaction between Cathepsin X and heparin has been revealed by affinity chromatography using heparin-Sepharose. Conformational changes were observed to accompany heparin-Cathepsin X interaction by far UV-circular dichroism at both acidic (4.5) and neutral (7.4) pH. These conformational changes promoted a 4-fold increase in the dissociation constant of the enzyme-substrate interaction and increased 2.6-fold the kcat value also. The interaction between Cathepsin X and heparin or heparan sulfate is specific since dermatan sulfate, chondroitin sulfate, and hyaluronic acid had no effect on the Cathepsin X activity. Using flow cytometry Cathepsin X was shown to bind cell surface heparan sulfate proteoglycans in wild-type CHO cells but not in CHO-745 cells, which are deficient in glycosaminoglycan synthesis. Moreover, fluorescently labeled Cathepsin X was shown by confocal microscopy to be endocytosed by wild-type CHO cells, but not by CHO-745 cells. These results demonstrate the existence of an endocytosis mechanism of Cathepsin X by the CHO cells dependent on heparan sulfate proteoglycans present at the cell surface, thus strongly suggesting that heparan sulfate proteoglycans can regulate the cellular trafficking and the enzymatic activity of Cathepsin X.
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Recombinant human Cathepsin X is a carboxymonopeptidase only: a comparison with Cathepsins B and L.
Biological chemistry, 2005Co-Authors: Luciano Puzer, Maria Helena S. Cezari, Luiz Juliano, Dušan Turk, Boris Turk, Ivica Stefe, Simone S. Cotrin, Izaura Y. Hirata, Maria A. Juliano, Adriana K CarmonaAbstract:The S 1 and S 2 subsite specificity of recombinant human Cathepsins X was studied using fluorescence resonance energy transfer (FRET) peptides with the general sequences Abz-Phe-Xaa-Lys(Dnp)-OH and Abz-Xaa-Arg-Lys(Dnp)-OH, respectively (Abz=ortho-aminobenzoic acid and Dnp=2,4-dinitrophenyl; Xaa=various amino acids). Cathepsin X cleaved all substrates exclusively as a carboxymonopeptidase and exhibited broad specificity. For comparison, these peptides were also assayed with Cathepsins B and L. Cathepsin L hydrolyzed the majority of them with similar or higher catalytic efficiency than Cathepsin X, acting as an endopeptidase mimicking a carboxymonopeptidase (pseudo-carboxymonopeptidase). In contrast, Cathepsin B exhibited poor catalytic efficiency with these substrates, acting as a carboxydipeptidase or an endopeptidase. The S 1 ' subsite of Cathepsin X was mapped with the peptide series Abz-Phe-Arg-Xaa-OH and the enzyme preferentially hydrolyzed substrates with hydrophobic residues in the P 1 ' position.
Johanna A Joyce - One of the best experts on this subject based on the ideXlab platform.
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cysteine Cathepsin proteases regulators of cancer progression and therapeutic response
Nature Reviews Cancer, 2015Co-Authors: Oakley C Olson, Johanna A JoyceAbstract:Cysteine Cathepsin protease activity is frequently dysregulated in the context of neoplastic transformation. Increased activity and aberrant localization of proteases within the tumour microenvironment have a potent role in driving cancer progression, proliferation, invasion and metastasis. Recent studies have also uncovered functions for Cathepsins in the suppression of the response to therapeutic intervention in various malignancies. However, Cathepsins can be either tumour promoting or tumour suppressive depending on the context, which emphasizes the importance of rigorous in vivo analyses to ascertain function. Here, we review the basic research and clinical findings that underlie the roles of Cathepsins in cancer, and provide a roadmap for the rational integration of Cathepsin-targeting agents into clinical treatment.
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cysteine Cathepsin proteases regulators of cancer progression and therapeutic response
Nature Reviews Cancer, 2015Co-Authors: Oakley C Olson, Johanna A JoyceAbstract:Increased activity and aberrant localization of cysteine Cathepsin proteases within the tumour microenvironment have potent roles in driving cancer progression. This Review discusses the roles of Cathepsins and provides a roadmap for the rational integration of Cathepsin-targeting agents into clinical treatment.
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deficiency for the cysteine protease Cathepsin l impairs myc induced tumorigenesis in a mouse model of pancreatic neuroendocrine cancer
PLOS ONE, 2015Co-Authors: Nicola R Brindle, Johanna A Joyce, Fanya Rostker, Elizabeth R Lawlor, Lamorna Swigartbrown, Gerard I Evan, Douglas Hanahan, Ksenya ShchorsAbstract:Motivated by the recent implication of cysteine protease Cathepsin L as a potential target for anti-cancer drug development, we used a conditional MycERTAM;Bcl-xL model of pancreatic neuroendocrine tumorigenesis (PNET) to assess the role of Cathepsin L in Myc-induced tumor progression. By employing a cysteine Cathepsin activity probe in vivo and in vitro, we first established that Cathepsin activity increases during the initial stages of MycERTAM;Bcl-xL tumor development. Among the Cathepsin family members investigated, only Cathepsin L was predominately produced by beta-tumor cells in neoplastic pancreata and, consistent with this, Cathepsin L mRNA expression was rapidly upregulated following Myc activation in the beta cell compartment. By contrast, Cathepsins B, S and C were highly enriched in tumor-infiltrating leukocytes. Genetic deletion of Cathepsin L had no discernible effect on the initiation of neoplastic growth or concordant angiogenesis. However, the tumors that developed in the Cathepsin L-deficient background were markedly reduced in size relative to their typical wild-type counterparts, indicative of a role for Cathepsin L in enabling expansive tumor growth. Thus, genetic blockade of Cathepsin L activity is inferred to retard Myc-driven tumor growth, encouraging the potential utility of pharmacological inhibitors of cysteine Cathepsins in treating late stage tumors.
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macrophages and Cathepsin proteases blunt chemotherapeutic response in breast cancer
Genes & Development, 2011Co-Authors: Tanaya Shree, Oakley C Olson, Benelita T Elie, Jemila C Kester, Alfred L Garfall, Kenishana Simpson, Katherine M Bellmcguinn, Emily C Zabor, Edi Brogi, Johanna A JoyceAbstract:The microenvironment is known to critically modulate tumor progression, yet its role in regulating treatment response is poorly understood. Here we found increased macrophage infiltration and Cathepsin protease levels in mammary tumors following paclitaxel (Taxol) chemotherapy. Cathepsin-expressing macrophages protected against Taxol-induced tumor cell death in coculture, an effect fully reversed by Cathepsin inhibition and mediated partially by Cathepsins B and S. Macrophages were also found to protect against tumor cell death induced by additional chemotherapeutics, specifically etoposide and doxorubicin. Combining Taxol with Cathepsin inhibition in vivo significantly enhanced efficacy against primary and metastatic tumors, supporting the therapeutic relevance of this effect. Additionally incorporating continuous low-dose cyclophosphamide dramatically impaired tumor growth and metastasis and improved survival. This study highlights the importance of integrated targeting of the tumor and its microenvironment and implicates macrophages and Cathepsins in blunting chemotherapeutic response.
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distinct roles for cysteine Cathepsin genes in multistage tumorigenesis
Genes & Development, 2006Co-Authors: Vasilena Gocheva, Christoph Peters, Douglas Hanahan, Thomas Reinheckel, Wei Zeng, David S Klimstra, Johanna A JoyceAbstract:Multiple types of degradative enzymes, including Cathepsins of the cysteine protease family, have been implicated in the regulation of angiogenesis and invasion during cancer progression. Several cysteine Cathepsins are up-regulated in a mouse model of pancreatic islet cell carcinogenesis (RIP1-Tag2), and tumor progression is impaired following their collective pharmacologic inhibition. Using null mutations of four of the implicated cysteine Cathepsins, we have now dissected their individual roles in cancer development. Mutants of Cathepsins B or S impaired tumor formation and angiogenesis, while Cathepsin B or L knockouts retarded cell proliferation and tumor growth. Absence of any one of these three genes impaired tumor invasion. In contrast, removal of Cathepsin C had no effect on either tumor formation or progression. We have identified E-cadherin as a target substrate of Cathepsins B, L, and S, but not Cathepsin C, potentially explaining their differential effects on tumor invasion. Furthermore, we detected analogous increases in Cathepsin expression in human pancreatic endocrine neoplasms, and a significant association between increased levels of Cathepsins B and L and tumor malignancy. Thus individual cysteine Cathepsin genes make distinctive contributions to tumorigenesis.
Dieter Bromme - One of the best experts on this subject based on the ideXlab platform.
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role of cysteine Cathepsins in extracellular proteolysis
2011Co-Authors: Dieter Bromme, Susan WilsonAbstract:Cysteine Cathepsins are lysosomal proteases with housekeeping as well as highly specialized functions. Although their activities are optimal at lysosomal acidic and reducing conditions, Cathepsins can significantly contribute to the degradation of the extracellular matrix. This may happen under physiological conditions as in Cathepsin K-mediated bone resorption or under pathological conditions. Extracellular matrix degradation can occur extracellularly by the secretion of Cathepsins or intracellularly following the endocytosis of matrix material. Under physiological conditions, the extracellular matrix is safeguarded against Cathepsin activities by its neutral pH, oxidative environment, and high levels of potent endogenous Cathepsin inhibitors. However, these barriers can be overcome by pericellular acidification and pathophysiologically reduced antiCathepsin concentrations. Whereas matrix metalloproteases are primarily responsible for the homeostasis of the extracellular matrix, cysteine proteases contribute to its destruction under disease conditions. The development of Cathepsin inhibitors as anti matrix-degrading drugs appears to be a successful strategy.
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biochemical properties and regulation of Cathepsin k activity
Biochimie, 2008Co-Authors: Fabien Lecaille, Dieter Bromme, Gilles LalmanachAbstract:Cysteine Cathepsins (11 in humans) are mostly located in the acidic compartments of cells. They have been known for decades to be involved in intracellular protein degradation as housekeeping proteases. However, the discovery of new Cathepsins, including Cathepsins K, V and F, has provided strong evidence that they also participate in specific biological events. This review focuses on the current knowledge of Cathepsin K, the major bone cysteine protease, which is a drug target of clinical interest. Nevertheless, we will not discuss recent developments in Cathepsin K inhibitor design since they have been extensively detailed elsewhere. We will cover features of Cathepsin K structure, cellular and tissue distribution, substrate specificity, and regulation (pH, propeptide, glycosaminoglycans, oxidants), and its putative roles in physiological or pathophysiological processes. Finally, we will review the kinetic data of its inhibition by natural endogenous inhibitors (stefin B, cystatin C, H- and L-kininogens).
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The S2 subsites of Cathepsins K and L and their contribution to collagen degradation
Protein Science, 2007Co-Authors: Fabien Lecaille, Dieter Bromme, Shafinaz Chowdhury, Enrico O. Purisima, Gilles LalmanachAbstract:The exchange of residues 67 and 205 of the S2 pocket of human cysteine Cathepsins K and L induces a permutation of their substrate specificity toward fluorogenic peptide substrates. While the Cathepsin L-like Cathepsin K (Tyr67Leu/Leu205Ala) mutant has a marked preference for Phe, the Leu67Tyr/Ala205Leu Cathepsin L variant shows an effective Cathepsin K-like preference for Leu and Pro. A similar turnaround of inhibition was observed by using specific inhibitors of Cathepsin K [1-(N-Benzyloxycarbonyl-leucyl)-5-(N-Boc-phenylalanyl-leucyl)carbohydrazide] and Cathepsin L [N-(4-biphenylacetyl)-S-methylcysteine-(D)-Arg-Phe-β-phenethylamide]. Molecular modeling studies indicated that mutations alter the character of both S2 and S3 subsites, while docking calculations were consistent with kinetics data. The Cathepsin K-like Cathepsin L was unable to mimic the collagen-degrading activity of Cathepsin K against collagens I and II, DQ-collagens I and IV, and elastin-Congo Red. In summary, double mutations of the S2 pocket of Cathepsins K (Y67L/L205A) and L (L67Y/A205L) induce a switch of their enzymatic specificity toward small selective inhibitors and peptidyl substrates, confirming the key role of residues 67 and 205. However, mutations in the S2 subsite pocket of Cathepsin L alone without engineering of binding sites to chondroitin sulfate are not sufficient to generate a Cathepsin K-like collagenase, emphasizing the pivotal role of the complex formation between glycosaminoglycans and Cathepsin K for its unique collagenolytic activity.
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Cathepsin v a novel and potent elastolytic activity expressed in activated macrophages
Journal of Biological Chemistry, 2004Co-Authors: Yoshiyuki Yasuda, Matthew Bogyo, Doron C Greenbaum, Ekkehard Weber, Dieter BrommeAbstract:Atherosclerosis is characterized by a thickening and loss of elasticity of the arterial wall. Loss of elasticity has been attributed to the degradation of the arterial elastin matrix. Cathepsins K and S are papain-like cysteine proteases with known elastolytic activities, and both enzymes have been identified in macrophages present in plaque areas of diseased blood vessels. Here we demonstrate that macrophages express a third elastolytic cysteine protease, Cathepsin V, which exhibits the most potent elastase activity yet described among human proteases and that Cathepsin V is present in atherosclerotic plaque specimens. Approximately 60% of the total elastolytic activity of macrophages can be attributed to cysteine proteases with Cathepsins V, K, and S contributing equally. From this 60%, two-thirds occur extracellularly and one-third intracellularly with the latter credited to Cathepsin V. Ubiquitously expressed glycosaminoglycans (GAGs) such as chondroitin sulfate specifically inhibit the elastolytic activities of Cathepsins V and K via the formation of specific Cathepsin-GAG complexes. In contrast, Cathepsin S, which does not form complexes with chondroitin sulfate is not inhibited; thus suggesting a specific regulation of elastolytic activities of Cathepsins by GAGs. Because the GAG content is reduced in atherosclerotic plaques, an increase of Cathepsins V and K activities may accelerate the destruction of the elastin matrix in diseased arteries.
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regulation of collagenase activities of human Cathepsins by glycosaminoglycans
Journal of Biological Chemistry, 2004Co-Authors: Yoshiyuki Yasuda, Matthew Bogyo, Norman Katz, Ronald E Gordon, Gregg B Fields, Dieter BrommeAbstract:Cathepsin K, a lysosomal papain-like cysteine protease, forms collagenolytically highly active complexes with chondroitin sulfate and represents the most potent mammalian collagenase. Here we demonstrate that complex formation with glycosaminoglycans (GAGs) is unique for Cathepsin K among human papain-like cysteine proteases and that different GAGs compete for the binding to Cathepsin K. GAGs predominantly expressed in bone and cartilage, such as chondroitin and keratan sulfates, enhance the collagenolytic activity of Cathepsin K, whereas dermatan, heparan sulfate, and heparin selectively inhibit this activity. Moreover, GAGs potently inhibit the collagenase activity of other cysteine proteases such as Cathepsins L and S at 37 °C. Along this line MMP1-generated collagen fragments in the presence of GAGs are stable against further degradation at 28 °C by all Cathepsins but Cathepsin K, whereas thermal destabilization at 37 °C renders the fragments accessible to all Cathepsins. These results suggest a novel mechanism for the regulation of matrix protein degradation by GAGs. It further implies that Cathepsin K represents the only lysosomal collagenolytic activity under physiologically relevant conditions.
Dušan Turk - One of the best experts on this subject based on the ideXlab platform.
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selective imaging of Cathepsin l in breast cancer by fluorescent activity based probes
Chemical Science, 2018Co-Authors: Marcin Poreba, Wioletta Rut, Matej Vizovisek, Katarzyna Groborz, Paulina Kasperkiewicz, Darren Finlay, Kristiina Vuori, Dušan TurkAbstract:Cysteine Cathepsins normally function in the lysosomal degradation system where they are critical for the maintenance of cellular homeostasis and the MHC II immune response, and have been found to have major roles in several diseases and in tumor progression. Selective visualization of individual protease activity within a complex proteome is of major importance to establish their roles in both normal and tumor cells, thereby facilitating our understanding of the regulation of proteolytic networks. A generally accepted means to monitor protease activity is the use of small molecule substrates and activity-based probes. However, there are eleven human cysteine Cathepsins, with a few of them displaying overlapping substrate specificity, making the development of small molecules that selectively target a single Cathepsin very challenging. Here, we utilized HyCoSuL, a positional scanning substrate approach, to develop a highly-selective fluorogenic substrate and activity-based probe for monitoring Cathepsin L activity in the breast cancer cell line MDA-MB-231. Use of this probe enabled us to distinguish the activity of Cathepsin L from that of other Cathepsins, particularly Cathepsin B, which is abundant and ubiquitously expressed in normal and transformed cell types. We found that Cathepsin L localization in MDA-MB-231 cells greatly overlaps with that of Cathepsin B, however, several Cathepsin L-rich lysosomes lacked Cathepsin B activity. Overall, these studies demonstrate that HyCoSuL-derived small molecule probes are valuable tools to image Cathepsin L activity in living cells. This approach thus enables evaluation of Cathepsin L function in tumorigenesis and is applicable to other cysteine Cathepsins.
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the future of cysteine Cathepsins in disease management
Trends in Pharmacological Sciences, 2017Co-Authors: Lovro Kramer, Dušan Turk, Boris TurkAbstract:Since the discovery of the key role of Cathepsin K in bone resorption, cysteine Cathepsins have been investigated by pharmaceutical companies as drug targets. The first clinical results from targeting Cathepsins by activity-based probes and substrates are paving the way for the next generation of molecular diagnostic imaging, whereas the majority of antibody–drug conjugates currently in clinical trials depend on activation by Cathepsins. Finally, Cathepsins have emerged as suitable vehicles for targeted drug delivery. It is therefore timely to review the future of Cathepsins in drug discovery. We focus here on inflammation-associated diseases because dysregulation of the immune system accompanied by elevated Cathepsin activity is a common feature of these conditions.
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Non-invasive in vivo imaging of tumour-associated Cathepsin B by a highly selective inhibitory DARPin.
Theranostics, 2017Co-Authors: Lovro Kramer, Markus A. Seeger, Markus G. Grütter, Miha Renko, Janja Završnik, Dušan Turk, Olga Vasiljeva, Vito Turk, Boris TurkAbstract:Cysteine Cathepsins often contribute to cancer progression due to their overexpression in the tumour microenvironment and therefore present attractive targets for non-invasive diagnostic imaging. However, the development of highly selective and versatile small molecule probes for Cathepsins has been challenging. Here, we targeted tumour-associated Cathepsin B using designed ankyrin repeat proteins (DARPins). The selective DARPin 8h6 inhibited Cathepsin B with picomolar affinity (Ki = 35 pM) by binding to a site with low structural conservation in Cathepsins, as revealed by the X-ray structure of the complex. DARPin 8h6 blocked Cathepsin B activity in tumours ex vivo and was successfully applied in in vivo optical imaging in two mouse breast cancer models, in which Cathepsin B was bound to the cell membrane or secreted to the extracellular milieu by tumour and stromal cells. Our approach validates Cathepsin B as a promising diagnostic and theranostic target in cancer and other inflammation-associated diseases.
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inhibitory fragment from the p41 form of invariant chain can regulate activity of cysteine Cathepsins in antigen presentation
Journal of Biological Chemistry, 2008Co-Authors: Marko Mihelic, Andreja Dobersek, Gregor Guncar, Dušan TurkAbstract:Abstract Cysteine Cathepsins play an indispensable role in proteolytic processing of the major histocompatibility complex class II-associated invariant chain (Ii) and foreign antigens in a number of antigen presenting cells. Previously it was shown that a fragment of 64 residues present in the p41 form of the Ii (p41 fragment) selectively inhibits the endopeptidase Cathepsin L, whereas the activity of Cathepsin S remains unaffected. Comparison of structures indicated that the selectivity of interactions between cysteine Cathepsins and the p41 fragment is far from being understood and requires further investigation. The p41 fragment has now been shown also to inhibit human Cathepsins V, K, and F (also, presumably, O) and mouse Cathepsin L with Ki values in the low nanomolar range. These Ki values are sufficiently low to ensure complex formation at physiological concentrations. In addition we have found that the p41 fragment can inhibit Cathepsin S too. These findings suggest that regulation of the proteolytic activity of most of the cysteine Cathepsins by the p41 fragment is an important and widespread control mechanism of antigen presentation.
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Recombinant human Cathepsin X is a carboxymonopeptidase only: a comparison with Cathepsins B and L.
Biological chemistry, 2005Co-Authors: Luciano Puzer, Maria Helena S. Cezari, Luiz Juliano, Dušan Turk, Boris Turk, Ivica Stefe, Simone S. Cotrin, Izaura Y. Hirata, Maria A. Juliano, Adriana K CarmonaAbstract:The S 1 and S 2 subsite specificity of recombinant human Cathepsins X was studied using fluorescence resonance energy transfer (FRET) peptides with the general sequences Abz-Phe-Xaa-Lys(Dnp)-OH and Abz-Xaa-Arg-Lys(Dnp)-OH, respectively (Abz=ortho-aminobenzoic acid and Dnp=2,4-dinitrophenyl; Xaa=various amino acids). Cathepsin X cleaved all substrates exclusively as a carboxymonopeptidase and exhibited broad specificity. For comparison, these peptides were also assayed with Cathepsins B and L. Cathepsin L hydrolyzed the majority of them with similar or higher catalytic efficiency than Cathepsin X, acting as an endopeptidase mimicking a carboxymonopeptidase (pseudo-carboxymonopeptidase). In contrast, Cathepsin B exhibited poor catalytic efficiency with these substrates, acting as a carboxydipeptidase or an endopeptidase. The S 1 ' subsite of Cathepsin X was mapped with the peptide series Abz-Phe-Arg-Xaa-OH and the enzyme preferentially hydrolyzed substrates with hydrophobic residues in the P 1 ' position.
Guo-ping Shi - One of the best experts on this subject based on the ideXlab platform.
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cysteine protease Cathepsins in cardiovascular disease from basic research to clinical trials
Nature Reviews Cardiology, 2018Co-Authors: Guo-ping Shi, Conglin Liu, Junli Guo, Xian Zhang, Galina K Sukhova, Peter LibbyAbstract:Cysteine protease Cathepsins have traditionally been considered as lysosome-restricted proteases that mediate proteolysis of unwanted proteins. However, studies from the past decade demonstrate that these proteases are localized not only in acidic compartments (endosomes and lysosomes), where they participate in intracellular protein degradation, but also in the extracellular milieu, plasma membrane, cytosol, nucleus, and nuclear membrane, where they mediate extracellular matrix protein degradation, cell signalling, and protein processing and trafficking through the plasma and nuclear membranes and between intracellular organelles. Studies in experimental disease models and on Cathepsin-selective inhibitors, as well as plasma and tissue biomarker data from animal models and humans, have verified the participation of cysteinyl Cathepsins in the pathogenesis of many cardiovascular diseases, including atherosclerosis, myocardial infarction, cardiac hypertrophy, cardiomyopathy, abdominal aortic aneurysms, and hypertension. Clinical trials of Cathepsin inhibitors in chronic inflammatory diseases suggest the utility of these inhibitors for the treatment of cardiovascular diseases and associated complications. Moreover, development of cell transfer technologies that enable ex vivo cell treatment with Cathepsin inhibitors might limit the unwanted systemic effects of Cathepsin inhibition and provide new avenues for targeting cysteinyl Cathepsins. In this Review, we summarize the available evidence implicating cysteinyl Cathepsins in the pathogenesis of cardiovascular diseases, discuss their potential as biomarkers of disease progression, and explore the potential of Cathepsin inhibitors for the treatment of cardiovascular diseases.
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expression of the elastolytic Cathepsins s and k in human atheroma and regulation of their production in smooth muscle cells
Journal of Clinical Investigation, 1998Co-Authors: Galina K Sukhova, Harold A. Chapman, Guo-ping Shi, Daniel I Simon, Peter LibbyAbstract:Formation of the atherosclerotic intima must involve altered metabolism of the elastin-rich arterial extracellular matrix. Proteases potentially involved in these processes remain unclear. This study examined the expression of the potent elastases Cathepsins S and K in human atheroma. Normal arteries contained little or no Cathepsin K or S. In contrast, macrophages in atheroma contained abundant immunoreactive Cathepsins K and S. Intimal smooth muscle cells (SMC), especially cells appearing to traverse the internal elastic laminae, also contained these enzymes. Extracts of atheromatous tissues had approximately twofold greater elastase-specific activity than extracts of uninvolved arteries, mostly due to cysteine proteases. Cultured human SMC displayed no immunoreactive Cathepsins K and S and exhibited little or no elastolytic activity when incubated with insoluble elastin. SMC stimulated with the atheroma-associated cytokines IL-1beta or IFN-gamma secreted active Cathepsin S and degraded substantial insoluble elastin (15-20 microg/10(6) cells/24 h). A selective inhibitor of Cathepsin S blocked > 80% of this elastolytic activity. The presence of Cathepsins K and S at sites of vascular matrix remodeling and the ability of SMC and macrophages to use these enzymes to degrade elastin supports a role for elastolytic Cathepsins in vessel wall remodeling and identifies novel therapeutic targets in regulating plaque stability.
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human Cathepsin s chromosomal localization gene structure and tissue distribution
Journal of Biological Chemistry, 1994Co-Authors: Guo-ping Shi, A C Webb, K E Foster, Joan H M Knoll, Cynthia A Lemere, J S Munger, Harold A. ChapmanAbstract:The human lysosomal cysteine proteinases, Cathepsins H, L, and B, have been mapped to chromosomes 15, 9, and 8, respectively, and the genomic structures of Cathepsins L and B have been determined. We report here the chromosomal localization and partial gene structure for a recently sequenced human cysteine proteinase, Cathepsin S. A 20-kilobase pair genomic clone of the human Cathepsin S gene was isolated from a human fibroblast genomic library and used to map the human Cathepsin S gene to chromosome 1q21 by fluorescence in situ hybridization. This clone contains exons 1 through 5, introns 1 through 4, part of intron 5, and > 7 kilobase pairs of the 5'-flanking sequence. The gene structure of human Cathepsin S is similar to that of Cathepsin L through the first 5 exons, except that Cathepsin S introns are substantially larger. Sequencing of the 5'-flanking region revealed, similar to human Cathepsin B, no classical TATA or CAAT box. In contrast to Cathepsin B, Cathepsin S contains only two SP1 and at least 18 AP1 binding sites that potentially could be involved in regulation of the gene. This 5'-flanking region also contains CA microsatellites. The presence of AP1 sites and CA microsatellites suggest that Cathepsin S can be specifically regulated. Results of Northern blotting using probes for human Cathepsins B, L, and S are consistent with this hypothesis; only Cathepsin S shows a restricted tissue distribution, with highest levels in spleen, heart, and lung. In addition, immunostaining of lung tissue demonstrated detectable Cathepsin S only in lung macrophages. The high level of expression in the spleen and in phagocytes suggests that Cathepsin S may have a specific function in immunity, perhaps related to antigen processing.
