The Experts below are selected from a list of 1716 Experts worldwide ranked by ideXlab platform
Randal A Skidgel - One of the best experts on this subject based on the ideXlab platform.
-
Carboxypeptidase M is a positive allosteric Modulator of the kinin b1 receptor
Journal of Biological Chemistry, 2013Co-Authors: Xianming Zhang, Randal A SkidgelAbstract:Abstract Ligand binding to extracellular doMains of G protein-coupled receptors can result in novel and nuanced allosteric effects on receptor signaling. We previously showed that the protein-protein interaction of Carboxypeptidase M (CPM) and kinin B1 receptor (B1R) enhances B1R signaling in two ways: 1. Kinin binding to CPM causes a conforMational activation of the B1R; 2. CPM generated des-Arg-kinin agonist is efficiently delivered to the B1R. Here, we show CPM is also a positive allosteric Modulator of B1R signaling to its agonist, des-Arg10-kallidin (DAKD). In HEK cells stably transfected with B1R, co-expression of CPM enhanced DAKD stiMulated increases in intracellular Ca2+ or phosphoinositide turnover by a leftward shift of the dose-response curve without changing the MaxiMuM. CPM increased B1R affinity for DAKD by ~5-fold, but had no effect on basal B1R-dependent phosphoinositide turnover. Soluble, recoMbinant CPM bound to HEK cells expressing B1Rs without stiMulating receptor signaling. CPM's positive allosteric action was independent of enzyMe activity, but depended on interaction of its C-terMinal doMain with the B1R extracellular loop 2. Disruption of the CPM/B1R interaction or knockdown of CPM in cytokine-treated priMary huMan endothelial cells inhibited the allosteric enhanceMent of CPM on B1R DAKD binding or ERK1/2 activation. CPM also enhanced the DAKD-induced B1R conforMational change as detected by increased intraMolecular fluorescence or bioluMinescence resonance energy transfer. Thus, CPM binding to extracellular loop 2 of the B1R results in positive allosteric Modulation of B1R signaling and disruption of this interaction could provide a novel therapeutic approach to reduce pathological B1R signaling.
-
Carboxypeptidase M augMents kinin B1 receptor signaling by conforMational crosstalk and enhances endothelial nitric oxide output.
Biological Chemistry, 2013Co-Authors: Xianming Zhang, Fulong Tan, Viktor Brovkovych, Yongkang Zhang, Jessica L. Lowry, Randal A SkidgelAbstract:G protein-coupled receptors (GPCRs) are the largest class of MeMbrane proteins that play key roles in transducing extracellular signals to intracellular proteins to generate cellular responses. The kinin GPCRs, naMed B1 (B1R) and B2 (B2R) are responsible for Mediating the biological responses to kinin peptides released froM the precursor kininogens. Bradykinin or kallidin are agonists for B2Rs whereas their Carboxypeptidase-generated Metabolites, des-Arg9-bradykinin or des-Arg10-kallidin are specific agonists for B1Rs. Here we review the evidence for a critical role of MeMbrane-bound Carboxypeptidase M in facilitating B1R signaling by its ability to directly activate the receptor via conforMational crosstalk as well as generate its specific agonist. In endothelial cells, the Carboxypeptidase M/B1R interaction facilitates B1R-dependent high output nitric oxide under inflaMMatory conditions.
-
cross talk between Carboxypeptidase M and the kinin b1 receptor Mediates a new Mode of g protein coupled receptor signaling
Journal of Biological Chemistry, 2011Co-Authors: Xianming Zhang, Viktor Brovkovych, Yongkang Zhang, Randal A SkidgelAbstract:Abstract G protein-coupled receptor (GPCR) signaling is affected by forMation of GPCR hoMo- or heterodiMers, but GPCR regulation by other cell surface proteins is not well understood. We reported that the kinin B1 receptor (B1R) heterodiMerizes with MeMbrane Carboxypeptidase M (CPM), facilitating receptor signaling via CPM-Mediated conversion of bradykinin or kallidin to des-Arg kinin B1R agonists. Here, we found that a catalytically inactive CPM Mutant that still binds substrate (CPM-E264Q) also facilitates efficient B1R signaling by B2 receptor agonists bradykinin or kallidin. This response required co-expression of B1R and CPM-E264Q in the saMe cell, was disrupted by antibody that dissociates CPM froM B1R, and was not found with a CPM-E264Q-B1R fusion protein. An additional Mutation that reduced the affinity of CPM for C-terMinal Arg and increased the affinity for C-terMinal Lys inhibited the B1R response to bradykinin (with C-terMinal Arg) but generated a response to Lys9-bradykinin. CPM-E264Q-Mediated activation of B1Rs by bradykinin resulted in increased intraMolecular fluorescence resonance energy transfer (FRET) in a B1R FRET construct, siMilar to that generated directly by a B1R agonist. In cytokine-treated huMan lung Microvascular endothelial cells, disruption of B1R-CPM heterodiMers inhibited B1R-dependent NO production stiMulated by bradykinin and blocked the increased endothelial perMeability caused by treatMent with bradykinin and pyrogallol (a superoxide generator). Thus, CPM and B1Rs on cell MeMbranes forM a critical coMplex that potentiates B1R signaling. Kinin peptide binding to CPM causes a conforMational change in the B1R leading to intracellular signaling and reveals a new Mode of GPCR activation by a cell surface peptidase.
-
Carboxypeptidase M and kinin b1 receptors interact to facilitate efficient b1 signaling froM b2 agonists
Journal of Biological Chemistry, 2008Co-Authors: Xianming Zhang, Yongkang Zhang, Randal A SkidgelAbstract:Abstract Kinin B1 receptor (B1R) expression is induced by injury or inflaMMatory Mediators, and its signaling produces both beneficial and deleterious effects. Kinins cleaved froM kininogen are agonists of the B2R and Must be processed by a Carboxypeptidase to generate B1R agonists des-Arg9-bradykinin or des-Arg10-kallidin. Carboxypeptidase M (CPM) is a MeMbrane protein potentially well suited for this function. Here we show that CPM expression is required to generate a B1R-dependent increase in [Ca2+]i in cells stiMulated with B2R agonists kallidin or bradykinin. CPM and the B1R interact on the cell MeMbrane, as shown by co-iMMunoprecipitation, cross-linking, and fluorescence resonance energy transfer analysis. CPM and B1R are also co-localized in lipid raft/caveolin-enriched MeMbrane fractions, as deterMined by gradient centrifugation. TreatMent of cells co-expressing CPM and B1R with Methyl-β-cyclodextrin to disrupt lipid rafts reduced the B1R-dependent increase in [Ca2+]i in response to B2R agonists, whereas cholesterol treatMent enhanced the response. A Monoclonal antibody to the C-terMinal β-sheet doMain of CPM reduced the B1R response to B2R agonists without inhibiting CPM. Cells expressing a novel fusion protein containing CPM at the N terMinus of the B1R also increased [Ca2+]i when stiMulated with B2R agonists, but the response was not reduced by Methyl-β-cyclodextrin or CPM antibody. A B1R- and CPM-dependent calciuM signal in response to B2R agonist bradykinin was also found in endothelial cells that express both proteins. Thus, a close relationship of B1Rs and CPM on the MeMbrane is required for efficiently generating B1R signals, which play iMportant roles in inflaMMation.
-
Carboxypeptidase M in Brain and Peripheral Nerves
Journal of Neurochemistry, 2006Co-Authors: Akihiro Nagae, Peter A. Deddish, Robert P. Becker, Randal A Skidgel, Masahiro Abe, Fulong Tan, Conwell H. Anderson, Ervin G ErdosAbstract:Carboxypeptidase M (CPM), a plasMa MeMbrane-bound enzyMe, cleaves C-terMinal basic aMino acids with a neutral pH optiMuM. We studied its distribution in huMan, baboon, and dog brain and in dog peripheral nerves. Areas were dissected, hoMogenized, centrifuged, and assayed for activity with dansyl-Ala-Arg. The corpus callosuM and the pyraMidal and optic tract were especially rich in CPM, whereas basal ganglia and cortex had low activity. The identity of the basic Carboxypeptidase activity with CPM was shown by siMilarities in subcellular localization, MeMbrane attachMent, substrate hydrolysis, inhibition by a specific basic Carboxypeptidase inhibitor, and cross-reaction with anti-huMan CPM antiseruM. This antiseruM iMMunoprecipitated an average of 85% of the activity in huMan and baboon brain and approxiMately 66% in dog brain. CPM co-purified with Myelin extracted froM the brain. Consistent with results obtained in placenta and cultured kidney cells, CPM in the brain appears to be MeMbrane-bound via a phosphatidylinositol glycan anchor. In the peripheral nerves, the specific activity in dog sciatic nerve and in vagus was high (98 and 149 nMol/h/Mg of protein, respectively). In iMMunohistocheMical studies, glia in the brain, which appear to be oligodendrocytes or astrocytes, and the outer aspects of Myelin sheaths and Schwann cells in sciatic and vagus nerves were stained. We conclude that in soMe areas of the CNS and the PNS, CPM is closely associated with Myelin and Myelin-forMing cells. Northern blot analysis revealed the presence of MRNA coding for CPM in the brain, showing that the enzyMe is indeed synthesized there.
Joao Bosco Pesquero - One of the best experts on this subject based on the ideXlab platform.
-
Interactions between Carboxypeptidase M and kinin B1 receptor in endothelial cells
Inflammation Research, 2019Co-Authors: Paola Bianchi Guimarães, Rafael Filippelli Silva, Carolina Caldas Hoff, Liliam Fernandes, Jair Ribeiro Chagas, Adriana Karaoglanovic Carmona, Clovis Ryuichi Nakaie, Michael Bader, Joao Bosco PesqueroAbstract:Introduction Carboxypeptidase M (CPM) is a glycosylphosphatidylinositol anchored enzyMe that plays an iMportant role in the kallikrein–kinin systeM (KKS). CPM catalytic doMain hydrolyzes Arg froM C-terMinal peptides (i.e., bradykinin and kallidin), generating des-Arg-kinins, the agonists of B_1 receptor (B_1R). It is known that CPM and kinin B_1R are co-localized in the plasMa MeMbrane MicrodoMains, where they interact with each other, facilitating receptor signaling. AiMs We hypothesized here that this CPM-B_1R interaction could also affect the activity of the enzyMe. Methods Thus, in this work, we evaluated the iMpact of B_1R presence or absence on CPM activity and expression, using priMary culture of Microvascular endothelial cells froM wild-type, kinin B_1R knockout Mice (B _1 ^−/− ), and transgenic rats overexpressing B_1 receptor exclusively in the endotheliuM. In addition, HEK293T cells, as wells as B _1 ^−/− priMary culture of endothelial cells, both transfected with B_1R, were also used. Results CPM expression and activity were downregulated in cells of knockout Mice coMpared to control and this reduction was rescued after B_1R transfection. Cells overexpressing B_1R presented higher levels of CPM MRNA, protein, and activity. This profile was reverted by pre-incubation with the B_1R antagonist, R715, in highly expressing receptor cells. Conclusions Our data show that kinin B_1R positively Modulates both CPM expression and activity, suggesting that CPM-B_1R interaction in MeMbrane MicrodoMains Might affect enzyMe activity, beyond interfering in receptors signaling. This work highlights the interactions aMong different coMponents of KKS and contributes to a better understanding of its patho-physiological role.
-
Interactions between Carboxypeptidase M and kinin B1 receptor in endothelial cells.
Inflammation Research, 2019Co-Authors: Paola Bianchi Guimarães, Rafael Filippelli Silva, Carolina Caldas Hoff, Liliam Fernandes, Jair Ribeiro Chagas, Adriana Karaoglanovic Carmona, Clovis Ryuichi Nakaie, Michael Bader, Joao Bosco PesqueroAbstract:Carboxypeptidase M (CPM) is a glycosylphosphatidylinositol anchored enzyMe that plays an iMportant role in the kallikrein–kinin systeM (KKS). CPM catalytic doMain hydrolyzes Arg froM C-terMinal peptides (i.e., bradykinin and kallidin), generating des-Arg-kinins, the agonists of B1 receptor (B1R). It is known that CPM and kinin B1R are co-localized in the plasMa MeMbrane MicrodoMains, where they interact with each other, facilitating receptor signaling. We hypothesized here that this CPM-B1R interaction could also affect the activity of the enzyMe. Thus, in this work, we evaluated the iMpact of B1R presence or absence on CPM activity and expression, using priMary culture of Microvascular endothelial cells froM wild-type, kinin B1R knockout Mice (B 1 −/− ), and transgenic rats overexpressing B1 receptor exclusively in the endotheliuM. In addition, HEK293T cells, as wells as B 1 −/− priMary culture of endothelial cells, both transfected with B1R, were also used. CPM expression and activity were downregulated in cells of knockout Mice coMpared to control and this reduction was rescued after B1R transfection. Cells overexpressing B1R presented higher levels of CPM MRNA, protein, and activity. This profile was reverted by pre-incubation with the B1R antagonist, R715, in highly expressing receptor cells. Our data show that kinin B1R positively Modulates both CPM expression and activity, suggesting that CPM-B1R interaction in MeMbrane MicrodoMains Might affect enzyMe activity, beyond interfering in receptors signaling. This work highlights the interactions aMong different coMponents of KKS and contributes to a better understanding of its patho-physiological role.
-
Multiple RNAs froM the Mouse Carboxypeptidase M locus: functional RNAs or transcription noise?
BMC Molecular Biology, 2009Co-Authors: Alessander O. Guimaraes, Fabiana Louise Motta, Viviane S. Alves, Beatriz A. Castilho, Joao Bosco PesqueroAbstract:Background A Major effort of the scientific coMMunity has been to obtain coMplete pictures of the genoMes of Many organisMs. This has been accoMplished Mainly by annotation of structural and functional eleMents in the genoMe sequence, a process that has been centred in the gene concept and, as a consequence, biased toward protein coding sequences. Recently, the explosion of transcriptoMe data generated and the discovery of Many functional non-protein coding RNAs have painted a More detailed and coMplex scenario for the genoMe. Here we analyzed the Mouse Carboxypeptidase M locus in this broader perspective in order to define the Mouse CPM gene structure and evaluate the existence of other transcripts froM the saMe genoMic region. Results BioinforMatic analysis of nucleotide sequences that Map to the Mouse CPM locus suggests that, in addition to the Mouse CPM MRNA, it expresses at least 33 different transcripts, Many of which seeM to be non-coding RNAs. We randoMly chose to evaluate experiMentally four of these extra transcripts. They are expressed in a tissue specific Manner, indicating that they are not artefacts or transcriptional noise. FurtherMore, one of these four extra transcripts shows expression patterns that differed considerably froM the other ones and froM the Mouse CPM gene, suggesting that there May be More than one transcriptional unit in this locus . In addition, we have confirMed the Mouse CPM gene RefSeq sequence by rapid aMplification of cDNA ends (RACE) and directional cloning. Conclusion This study supports the recent view that the Majority of the genoMe is transcribed and that Many of the resulting transcripts seeM to be non-coding RNAs froM introns of genes or froM independent transcriptional units. Although soMe of the inforMation on the transcriptoMe of Many organisMs May actually be artefacts or transcriptional noise, we argue that it can be experiMentally evaluated and used to find and define biological functional eleMents on the genoMe. FurtherMore, the transcription of other functional RNAs besides the protein coding RNA froM a specific genoMic locus iMposes extra care when designing and interpreting experiMents involving genetic Manipulations or expression detection and quantification.
-
Multiple RNAs froM the Mouse Carboxypeptidase M locus: functional RNAs or transcription noise?
BMC Molecular Biology, 2009Co-Authors: Alessander O. Guimaraes, Fabiana Louise Motta, Viviane S. Alves, Beatriz A. Castilho, Joao Bosco PesqueroAbstract:Background A Major effort of the scientific coMMunity has been to obtain coMplete pictures of the genoMes of Many organisMs. This has been accoMplished Mainly by annotation of structural and functional eleMents in the genoMe sequence, a process that has been centred in the gene concept and, as a consequence, biased toward protein coding sequences. Recently, the explosion of transcriptoMe data generated and the discovery of Many functional non-protein coding RNAs have painted a More detailed and coMplex scenario for the genoMe. Here we analyzed the Mouse Carboxypeptidase M locus in this broader perspective in order to define the Mouse CPM gene structure and evaluate the existence of other transcripts froM the saMe genoMic region.
-
High expression of huMan Carboxypeptidase M in Pichia pastoris: Purification and partial characterization
Brazilian Journal of Medical and Biological Research, 2006Co-Authors: Rogério Bastos Craveiro, Jorge L. Pesquero, J.d. Ramalho, Jair R. Chagas, Pamella Huey Mei Wang, Dulce Elena Casarini, Ronaldo C. Araujo, Joao Bosco PesqueroAbstract:Carboxypeptidase M (CPM) is an extracellular glycosylphosphatidyl-inositol-anchored MeMbrane glycoprotein, which reMoves the C-terMinal basic residues, lysine and arginine, froM peptides and proteins at neutral pH. CPM plays an iMportant role in the control of peptide horMones and growth factor activity on the cell surface. The present study was carried out to clone and express huMan CPM in the yeast Pichia pastoris in order to evaluate the iMportance of this enzyMe in physiological and pathological processes. The cDNA for the enzyMe was aMplified froM total placental RNA by RT-PCR and cloned in the vector pPIC9, which uses the Methanol oxidase proMoter and drives the expression of high levels of heterologous proteins in P. pastoris. The cpM gene, after cloning and transfection, was integrated into the yeast genoMe, which produced the active protein. The recoMbinant protein was secreted into the MediuM and the enzyMatic activity was Measured using the fluorescent substrate dansyl-Ala-Arg. The enzyMe was purified by a two-step protocol including gel filtration and ion-exchange chroMatography, resulting in a 1753-fold purified active protein (16474 RFU Mg protein-1 Min-1). This purification protocol perMitted us to obtain 410 Mg of the purified protein per liter of ferMentation MediuM. SDS-PAGE showed that recoMbinant CPM Migrated as a single band with a Molecular Mass siMilar to that of native placental enzyMe (62 kDa), suggesting that the expression of a glycosylated protein had occurred. These results deMonstrate for the first tiMe the establishMent of a Method using P. pastoris to express huMan CPM necessary to the developMent of specific antibodies and antagonists, and the analysis of the involveMent of this peptidase in different physiological and pathological processes
Anna Janowskawieczorek - One of the best experts on this subject based on the ideXlab platform.
-
Carboxypeptidase M expressed by huMan bone Marrow cells cleaves the c terMinal lysine of stroMal cell derived factor 1α another player in heMatopoietic steM progenitor cell Mobilization
Stem Cells, 2008Co-Authors: Leah A Marquezcurtis, Anne-marie Lambeir, Kathleen Deiteren, Ali Jalili, Neeta Shirvaikar, Anna JanowskawieczorekAbstract:Carboxypeptidase M (CPM) is a MeMbrane-bound zinc-dependent protease that cleaves C-terMinal basic residues, such as arginine or lysine, froM peptides/proteins. We exaMined whether CPM is expressed by heMatopoietic and stroMal cells and could degrade stroMal cell-derived factor (SDF)-1α, a potent cheMoattractant for heMatopoietic steM/progenitor cells (HSPC). We found that (a) CPM transcript is expressed by bone Marrow (BM) and Mobilized peripheral blood CD34+ cells, Myeloid, erythroid, and Megakaryocytic cell progenitors, Mononuclear cells (MNC), polyMorphonuclear cells (PMN), and stroMal cells, including MesenchyMal steM cells; and that (b) granulocyte-colony-stiMulating factor (G-CSF) significantly increases its expression at the gene and protein levels in MNC and PMN. Moreover, we found that recoMbinant CPM cleaves full-length SDF-1α (1–68) rapidly, reMoving the C-terMinal lysine and yielding des-lys SDF-1α (1–67). We deMonstrated that such CPM treatMent of SDF-1α reduced the in vitro cheMotaxis of HSPC, which, however, was preserved when the CPM was exposed to the Carboxypeptidase inhibitor dl-2-MercaptoMethyl-3-guanidino-ethylthiopropanoic acid. Thus, we present evidence that CPM is expressed by cells occurring in the BM MicroenvironMent and that the Mobilizing agent G-CSF strongly upregulates it in MNC and PMN. We suggest that cleavage of the C-terMinal lysine residue of SDF-1α by CPM leads to attenuated cheMotactic responses and could facilitate G-CSF-induced Mobilization of HSPC froM BM to peripheral blood. Disclosure of potential conflicts of interest is found at the end of this article.
Anne-marie Lambeir - One of the best experts on this subject based on the ideXlab platform.
-
and Renal Cell CarcinoMa: Expression in TuMor-Associated
2016Co-Authors: M Normal, Catherine J. Denis, Dirk Hendriks, Nathalie Van Acker, Martine De Bie, Erik Fransen, Mark M. Kockx, Human Kidney, Anne-marie LambeirAbstract:In 1984, a Carboxypeptidase N (CPN)–like enzyMe was identified in MeMbrane fractions of the huMan kidney (Skidgel, Johnson, and Erdos 1984). This new MeMber of the B-type Carboxypeptidases was naMed Carboxypeptidase M (CPM) because of its unique MeMbrane-bound feature (Skidgel et al. 1989). A huMan urinary basic carboxypepti-dase (different froM CPA, pancreatic CPB, or CPN) puri-fied earlier that year was identified later as the soluble forM of CPM (Skidgel, Davis, and Erdos 1984; McGwire and Skidgel 1995). Soluble CPM Most likely is responsible for the basic Carboxypeptidase activity reported for huMan urine froM healthy individuals and renal disease patients (HaMai et al. 1990). Besides the placenta and the lung, the kidney is considered an iMportant source of CPM. Although strong evidence exists for the expression of the peptidase in the huMan kidney, Mapping of CPM along renal structures and renal-specific cell types has never been perforMed. Although soMe basic Carboxypeptidases (particularly CPU) 470456 JHCXXX10.1369/0022155412470456Denis et al.CPM in HuMan Kidney and Renal Cell CarcinoM
-
CPM (Carboxypeptidase M)
Atlas of Genetics and Cytogenetics in Oncology and Haematology, 2014Co-Authors: Anne-marie LambeirAbstract:Review on CPM, with data on DNA/RNA, on the protein encoded and where the gene is iMplicated. Identity
-
The potential of Carboxypeptidase M as a therapeutic target in cancer.
Expert Opinion on Therapeutic Targets, 2013Co-Authors: Catherine J. Denis, Anne-marie LambeirAbstract:Introduction: In the recent literature, Carboxypeptidase M (CPM) eMerged as a potential cancer bioMarker. CPM Modulates receptor signaling of kinins, anaphylatoxins, and cheMokines. These CPM substrates affect proliferation, angiogenesis, and apoptosis of cancer cells. What is the evidence that CPM is a drug target for cancer therapy? Areas covered: The literature was searched using PubMed with the search terMs “Carboxypeptidase M” and/or “chroMosoMe 12q13-15” eventually coMbined with general terMs related to cancer. InforMation was retrieved froM the GEO database and Material of gene expression and proteoMic studies. Expert opinion: CPM is a part of the Molecular signature of Many cancers. There is good evidence that it is useful for the discriMination and stratification of cancer types, possibly in coMbination with other Markers such as EGFR and MDM2. Whether it is also a drug target reMains to be deterMined. Lung, kidney, brain, and the reproductive systeM contain relatively high levels of CPM, but its...
-
Carboxypeptidase M in apoptosis, adipogenesis and cancer
Clinica Chimica Acta, 2013Co-Authors: Catherine J. Denis, Kathleen Deiteren, Dirk Hendriks, Paul Proost, Anne-marie LambeirAbstract:This review covers Carboxypeptidase M (CPM) research that appeared in the literature since 2009. The focus is on aspects that are new or interesting froM a clinical perspective. Available research tools are discussed as well as their pitfalls and liMitations. Evidence is provided to suggest the potential involveMent of CPM in apoptosis, adipogenesis and cancer. This evidence derives froM the expression pattern of CPM and its putative substrates in cells and tissues. In recent years CPM eMerged as a potential cancer bioMarker, in well differentiated liposarcoMa where the CPM gene is co-aMplified with the oncogene MDM2; and in lung adenocarcinoMa where coexpression with EGFR correlates with poor prognosis. The available data call for extended investigation of the function of CPM in tuMor cells, tuMor-associated Macrophages, stroMal cells and tuMor neovascularisation. Such experiMents could be instruMental to validate CPM as a therapeutic target.
-
Mapping of Carboxypeptidase M in norMal huMan kidney and renal cell carcinoMa: expression in tuMor-associated neovasculature and Macrophages.
Journal of Histochemistry & Cytochemistry, 2012Co-Authors: Catherine J. Denis, Dirk Hendriks, Nathalie Van Acker, Stefanie De Schepper, Martine De Bie, Luc Andries, Erik Fransen, Mark M. Kockx, Anne-marie LambeirAbstract:Although the kidney generally has been regarded as an excellent source of Carboxypeptidase M (CPM), little is known about its renal-specific expression level and distribution. This study provides a detailed localization of CPM in healthy and diseased huMan kidneys. The results indicate a broad distribution of CPM along the renal tubular structures in the healthy kidney. CPM was identified at the parietal epitheliuM beneath the BowMan’s baseMent MeMbrane and in gloMerular Mesangial cells. Capillaries, podocytes, and Most interstitial cells were CPM negative. TuMor cells of renal cell carcinoMa subtypes lose CPM expression upon dedifferentiation. Tissue Microarray analysis deMonstrated a correlation between low CPM expression and tuMor cell type. CPM staining was intense on phagocytotic tuMor-associated Macrophages. IMMunoreactive CPM was also detected in the tuMor-associated vasculature. The absence of CPM in norMal renal blood vessels points toward a role for CPM in angiogenesis. Coexistence of CPM and the epiderMal growth factor receptor (EGFR) was detected in papillary renal cell carcinoMa. However, the different subcellular localization of CPM and EGFR argues against an interaction between these h proteins. The description of the distribution of CPM in huMan kidney forMs the foundation for further study of the (patho)physiological activities of CPM in the kidney.
Ioannis Tsakiris - One of the best experts on this subject based on the ideXlab platform.
-
Carboxypeptidase-M is regulated by lipids and CSFs in Macrophages and dendritic cells and expressed selectively in tissue granuloMas and foaM cells
Laboratory Investigation, 2012Co-Authors: Ioannis Tsakiris, Gyorgyike Soos, Zoltan Nemes, Daniel Torocsik, Adrienn Gyongyosi, Aniko Dozsa, Istvan Szatmari, Attila Szanto, Laszlo Igali, Ildiko MartonAbstract:GranuloMatous inflaMMations, characterized by the presence of activated Macrophages (MAs) forMing epithelioid cell (EPC) clusters, are usually easy to recognize. However, in aMbiguous cases the use of a MA Marker that expresses selectively in EPCs May be needed. Here, we report that Carboxypeptidase-M (CPM), a MA-differentiation Marker, is preferentially induced in EPCs of all granuloMa types studied, but not in resting MAs. As CPM is not expressed constitutively in MAs, this allows utilization of CPM-iMMunohistocheMistry in diagnostics of Minute granuloMa detection when dense non-granuloMatous MAs are also present. Despite this rule, hardly any detectable CPM was found in advanced/active tubercle caseous disease, albeit in early tuberculosis granuloMa, MAs still expressed CPM. Indeed, in vitro both the CPM-protein and -MRNA becaMe downregulated when MAs were infected with live Mycobacteria. In vitro , MA-CPM transcript is neither induced reMarkably by interferon- γ , known to cause classical MA activation, nor by IL-4, an alternative MA activator. Instead, CPM is selectively expressed in lipid-laden MAs, including the foaM cells of atherosclerotic plaques, xanthoMatous lesions and lipid pneuMonias. By using seruM, rich in lipids, and low-density lipoprotein (LDL) or VLDL, CPM upregulation could be reproduced in vitro in Monocyte-derived MAs both at transcriptional and protein levels, and the increase is repressed under lipid-depleted conditions. The Microarray analyses support the notion that CPM induction correlates with a robust progressive increase in CPM gene expression during Monocyte to MA Maturation and dendritic cell (DC) differentiation Mediated by granulocyte–MA-colony-stiMulating factor+IL-4. M-CSF alone also induced CPM. These results collectively indicate that CPM upregulation in MAs is preferentially associated with increased lipid uptake, and exposure to CSF, features of EPCs, also. Therefore, CPM-iMMunohistocheMistry is useful for granuloMa and foaM MA detections in tissue sections. FurtherMore, the present data offer CPM for the first tiMe to be a novel Marker and cellular player in lipid uptake and/or MetabolisM of MAs by proMoting foaM cell forMation.
-
The presence of Carboxypeptidase-M in tuMour cells signifies epiderMal growth factor receptor expression in lung adenocarcinoMas
Journal of Cancer Research and Clinical Oncology, 2008Co-Authors: Ioannis Tsakiris, Gyorgyike Soos, Zoltan Nemes, Sandor Sz. Kiss, Csilla Andras, Janos Szantó, Balazs DezsoAbstract:Purpose Carboxypeptidase-M (CPM) is a MeMbrane-bound peptidase that Metabolizes peptides, and is present in pneuMocytes. CPM hydrolyses the C-terMinal arginine of epiderMal growth factor (EGF) resulting in des-Arg^53-EGF which binds to the EGF receptor (EGFR) with an equal or greater affinity than native EGF. Therefore, this study focused on the possible presence of CPM in huMan lung adenocarcinoMas (ADC) and evaluated the relationship between CPM and EGFR by assessing the iMpact of expressions on patient clinical outcoMe. Methods This is a retrospective study of 110 patients who underwent resection of the priMary tuMour (92) or Metastatic tissues (18) for treatMent or diagnosis. IMMunohistocheMistry (IHC) for CPM and EGFR was Made in serial sections using standard Methods. Results This study deMonstrates for the first tiMe that 23.6% of ADCs express Carboxypeptidase-M (26/110), Mainly in MeMbrane-bound forMs. The aMounts and the extent of CPM within tuMours vary froM low levels to obviously overexpressed forMs. The iMMunohistocheMical positivity (+) for CPM in ADCs negatively correlated with disease survival. In addition, 80% of CPM^+ adenocarcinoMas (21/26) showed a coexpression with EGFR suggesting a high prevalence for coexistence. The follow up data indicated a significantly shorter 5-year survival tiMe for patients with CPM^+–EGFR^+ (double-positive) tuMours coMpared to those harbouring neoplasias negative for both proteins (9.5 vs. 60.4% survivals, P
-
The presence of Carboxypeptidase-M in tuMour cells signifies epiderMal growth factor receptor expression in lung adenocarcinoMas: the coexistence predicts a poor prognosis regardless of EGFR levels.
Journal of Cancer Research and Clinical Oncology, 2007Co-Authors: Ioannis Tsakiris, Gyorgyike Soos, Zoltan Nemes, Sandor Sz. Kiss, Csilla Andras, Janos Szantó, Balazs DezsoAbstract:Purpose Carboxypeptidase-M (CPM) is a MeMbrane-bound peptidase that Metabolizes peptides, and is present in pneuMocytes. CPM hydrolyses the C-terMinal arginine of epiderMal growth factor (EGF) resulting in des-Arg53-EGF which binds to the EGF receptor (EGFR) with an equal or greater affinity than native EGF. Therefore, this study focused on the possible presence of CPM in huMan lung adenocarcinoMas (ADC) and evaluated the relationship between CPM and EGFR by assessing the iMpact of expressions on patient clinical outcoMe.