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Cadherin
Kinds of Cadherin Terms modified by Cadherin Selected AbstractsCadherin 13 in cancerGENES, CHROMOSOMES AND CANCER, Issue 9 2010Alexandra V. Andreeva We review the evidence suggesting the involvement of Cadherin 13 (CDH13, T-cadherin, H-cadherin) in various cancers. CDH13 is an atypical member of the cadherin family, devoid of a transmembrane domain and anchored to the exterior surface of the plasma membrane via a glycosylphosphatidylinositol anchor. CDH13 is thought to affect cellular behavior largely through its signaling properties. It is often down-regulated in cancerous cells. CDH13 down-regulation has been associated with poorer prognosis in various carcinomas, such as lung, ovarian, cervical and prostate cancer. CDH13 re-expression in most cancer cell lines inhibits cell proliferation and invasiveness, increases susceptibility to apoptosis, and reduces tumor growth in in vivo models. These properties suggest that CDH13 may represent a possible target for therapy in some cancers. At the same time, CDH13 is up-regulated in blood vessels growing through tumors and promotes tumor neovascularization. In contrast to most cancer cell lines, CDH13 overexpression in endothelial cells promotes their proliferation and migration, and has a pro-survival effect. We also discuss molecular mechanisms that may regulate CDH13 expression and underlie its roles in cancer. © 2010 Wiley-Liss, Inc. [source] Single nucleotide polymorphisms in the cadherin 23 (CDH23) gene in Polish workers exposed to industrial noise,AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 4 2008Mariola Sliwinska-Kowalska Single nucleotide polymorphisms (SNPs) are the most frequent type of variation in the human genome and may underlie differential susceptibility to common genetic diseases. A candidate gene for susceptibility to noise-induced hearing loss (NIHL) is Cadherin 23 (CDH23). This study aimed to analyze genetic variation in the CDH23 gene in a group of 10 individuals derived from a cohort of 949 workers exposed to noise, and consisted of five persons from each of the resistant and susceptible extremes. DNA samples were collected and the coding exons of CDH23 were sequenced. We identified a total of 35 SNPs: 11 amino acid substitutions, 8 silent nucleotide changes, and 16 substitutions in intervening sequences. Ten of the 11 amino acid substitutions were previously shown also to segregate in a Cuban population. The nonsynonymous SNPs localized to the part of the gene encoding the extracellular domain of Cadherin 23, in particular ectodomains 5, 13, 14, 15, 16, 17, 19, and 22. One amino acid change occurred at a conserved position in ectodomain 5. Our results provide a framework for future study of polymorphisms in CDH23 as risk factor for NIHL. Am. J. Hum. Biol., 2008. Published 2008 Wiley-Liss, Inc. [source] Plasticity of Cadherin,Catenin Expression in the Melanocyte LineagePIGMENT CELL & MELANOMA RESEARCH, Issue 4 2000ALICE JOUNEAU Cadherins are calcium-dependent cell adhesion receptors with strong morphoregulatory functions. To mediate functional adhesion, cadherins must interact with actin cytoskeleton. Catenins are cytoplasmic proteins that mediate the interactions between cadherins and the cytoskeleton. In addition to their role in cell,cell adhesion, catenins also participate in signaling pathways that regulate cell growth and differentiation. Cadherins and catenins appear to be involved in melanocyte development and transformation. Here, we investigated the function of cadherin,catenin complexes in the normal development and transformation of melanocytes by studying the patterns of expression of the cell,cell adhesion molecules, E-, N- and P-cadherin, and the expression of their cytoplasmic partners, ,-, ,- and ,-catenin, during murine development. Similar analyses were performed in vitro using murine melanoblast, melanocyte, and melanoma cell lines in the presence and absence of keratinocytes, the cells with which melanocytes interact in vivo. Overall, the results suggest that the expression of cadherins and catenins is very plastic and depends on their environment as well as the transformation status of the cells. This plasticity is important in fundamental cellular mechanisms associated with normal and pathological ontogenesis, as well as with tumorigenesis. [source] Cadherin 11 promotes invasive behavior of fibroblast-like synoviocytesARTHRITIS & RHEUMATISM, Issue 5 2009Hans P. Kiener Objective To define the expression pattern of cadherin 11 in the destructive pannus tissue of patients with rheumatoid arthritis, and to determine whether cadherin 11 expression in fibroblast-like synoviocytes controls their invasive capacity. Methods Cadherin 11 expression in rheumatoid synovial tissue was evaluated using immunohistochemistry. To examine the role of cadherin 11 in regulating the invasive behavior of fibroblast-like synoviocytes, we generated L cell clones expressing wild-type cadherin 11, mutant cadherin 11, and empty vector,transfected controls. The invasive capacity of L cell transfectants and cultured fibroblast-like synoviocytes treated with a blocking cadherin 11,Fc fusion protein or control immunoglobulin was determined in Matrigel invasion assays. Results Immunohistochemical analysis revealed that cadherin 11 is abundantly expressed in cells at the cartilage,pannus junction in rheumatoid synovitis. Assays to determine invasion demonstrated a 2-fold increased invasive capacity of cadherin 11,transfected L cells compared with L cells transfected with E-cadherin or control vector. The invasive behavior of L cells stably transfected with a cadherin 11 construct that lacked the juxtamembrane cytoplasmic domain was diminished to the level of vector control L cells. Furthermore, treatment with the cadherin 11,Fc fusion protein diminished the invasive capacity of fibroblast-like synoviocytes. Conclusion The results of these in vitro studies implicate a role for cadherin 11 in promoting cell invasion and contribute insight into the invasive nature of fibroblast-like synoviocytes in chronic synovitis and rheumatoid arthritis. [source] Profilin-1 overexpression restores adherens junctions in MDA-MB-231 breast cancer cells in R-cadherin-dependent mannerCYTOSKELETON, Issue 12 2009Li Zou Abstract Profilin-1 (Pfn1), a ubiquitously expressed actin-binding protein, is downregulated in several different types of adenocarcinoma and elicits tumor-suppressive effect on breast cancer cell lines. MDA-MB-231 (MDA-231), a breast cancer cell line that displays all the characteristics of post-epithelial-to-mesenchymal transition and does not form cell,cell adhesion, can be reverted to an epithelioid phenotype by Pfn1 overexpression. This morphological transition is caused by restoration of adherens junctions (AJ) requiring Pfn1's interaction with actin. Pfn1 overexpression increases the expression level of R-cadherin (a type of cadherin that is endogenously expressed in the parental cell line) and restores AJ in MDA-231 cells in R-cadherin-dependent manner. These findings highlight important role of Pfn1 in the regulation of epithelial cell,cell adhesion. Cell Motil. Cytoskeleton 2009. © 2009 Wiley-Liss, Inc. [source] Temporal and spatial expression profiles of the Fat3 protein, a giant cadherin molecule, during mouse developmentDEVELOPMENTAL DYNAMICS, Issue 2 2007Shigenori Nagae Abstract Cadherins constitute a superfamily of cell,cell interaction molecules that participate in morphogenetic processes of animal development. Fat cadherins are the largest members of this superfamily, with 34 extracellular cadherin repeats. Classic Fat, identified in Drosophila, is known to regulate cell proliferation and planar cell polarity. Although 4 subtypes of Fat cadherin, Fat1, Fat2, Fat3, and Fat4/Fat-J, have been identified in vertebrates, their protein localization remains largely unknown. Here we describe the mRNA and protein distributions of Fat3 during mouse development. We found that Fat3 expression was restricted to the nervous system. In the brain, Fat3 was expressed in a variety of regions and axon fascicles. However, its strongest expression was observed in the olfactory bulb and retina. Detailed analysis of Fat3 in the developing olfactory bulb revealed that Fat3 mRNA was mainly expressed by mitral cells and that its proteins were densely localized along the dendrites of these cells as well as in their axons to some extent. Fat3 transcripts in the retina were expressed by amacrine and ganglion cells, and its proteins were concentrated in the inner plexiform layer throughout development. Based on these observations, we suggest that Fat3 plays a role in the interactions between neurites derived from specific subsets of neurons during development. Developmental Dynamics 236:534,543, 2007. © 2006 Wiley-Liss, Inc. [source] N-cadherin prodomain cleavage regulates synapse formation in vivoDEVELOPMENTAL NEUROBIOLOGY, Issue 8 2009Nazlie S. Latefi Abstract Cadherins are initially synthesized bearing a prodomain that is thought to limit adhesion during early stages of biosynthesis. Functional cadherins lack this prodomain, raising the intriguing possibility that cells may utilize prodomain cleavage as a means to temporally or spatially regulate adhesion after delivery of cadherin to the cell surface. In support of this idea, immunostaining for the prodomain of zebrafish N-cadherin revealed enriched labeling at neuronal surfaces at the soma and along axonal processes. To determine whether post-translational cleavage of the prodomain affects synapse formation, we imaged Rohon-Beard cells in zebrafish embryos expressing GFP-tagged wild-type N-cadherin (NCAD-GFP) or a GFP-tagged N-cadherin mutant expressing an uncleavable prodomain (PRON-GFP) rendering it nonadhesive. NCAD-GFP accumulated at synaptic microdomains in a developmentally regulated manner, and its overexpression transiently accelerated synapse formation. PRON-GFP was much more diffusely distributed along the axon and its overexpression delayed synapse formation. Our results support the notion that N-cadherin serves to stabilize pre- to postsynaptic contacts early in synapse development and suggests that regulated cleavage of the N-cadherin prodomain may be a mechanism by which the kinetics of synaptogenesis are regulated. © 2009 Wiley Periodicals, Inc. Develop Neurobiol 2009 [source] RhoA/ROCK and Cdc42 regulate cell-cell contact and N-cadherin protein level during neurodetermination of P19 embryonal stem cellsDEVELOPMENTAL NEUROBIOLOGY, Issue 3 2004Isabel Laplante Abstract RhoGTPases regulate actin-based signaling cascades and cellular contacts. In neurogenesis, their action modulates cell migration, neuritogenesis, and synaptogenesis. Murine P19 embryonal stem cells differentiate to neurons upon aggregation in the presence of retinoic acid, and we previously showed that RhoA and Cdc42 RhoGTPases are sequentially up-regulated during neuroinduction, suggesting a role at this very early developmental stage. In this work, incubation of differentiating P19 cells with C3 toxin resulted in decreased aggregate cohesion and cadherin protein level. In contrast, C3 effects were not observed in cells overexpressing recombinant dominant active RhoA. On the other hand, C3 did not affect cadherin in uninduced cells and their postmitotic neuronal derivatives, respectively expressing E- and N-cadherin. RhoA is thus influential on cell aggregation and cadherin expression during a sensitive time window that corresponds to the switch of E- to N-cadherin. Cell treatment with Y27632 inhibitor of Rho-associated-kinase ROCK, or advanced overexpression of Cdc42 by gene transfer of a constitutively active form of the protein reproduced C3 effects. RhoA-antisense RNA also reduced cadherin level and the size of cell aggregates, and increased the generation of fibroblast-like cells relative to neurons following neuroinduction. Colchicin, a microtubule disrupter, but not cytochalasin B actin poison, importantly decreased cadherin in neurodifferentiating cells. Overall, our results indicate that the RhoA/ROCK pathway regulates cadherin protein level and cell-cell interactions during neurodetermination, with an impact on the efficiency of the process. The effect on cadherin seems to involve microtubules. The importance of correct timing of RhoA and Cdc42 functional expression in neurogenesis is also raised. © 2004 Wiley Periodicals, Inc. J Neurobiol 60: 289,307, 2004 [source] Lymphocyte-expressed BILL-cadherin/cadherin-17 contributes to the development of B cells at two stagesEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 3 2005Kazuo Ohnishi Abstract The gene encoding BILL-cadherin/cadherin-17, a nonclassical cadherin expressed on B lymphocytes in a stage-and-site-specific manner, was inactivated by targeted disruption of its transmembrane/cytoplasmic portion-encoding parts. BILL-cadherin deficiency caused a threefold proB cell accumulation, as well as a reduction to half of the numbers of immature B cells in bone marrow. In spleen, CD21hiCD23lo marginal zone B cells were found reduced and the structure of the marginal zone was impaired. In addition, the size and number of germinal center as well as the number of PNA+ cells were significantly reduced in BILL-cadherin-deficient mice. In the peritoneal cavity of mutant mice IgM+Mac-1+CD5+ B1a cell, that express high BILL-cadherin in wild-type mice, was also reduced in number. The IgG1 and IgG3 antibody response to the T-independent antigen, TNP-Ficoll, was impaired in the mutant mice. These results indicate that BILL-cadherin participates in B lymphocyte development at least at two stages, first at the transition of pro/preB-I cells to preB-II cells possibly in association with surrogate light chain in bone marrow, and later at the point of development, accumulation and reactiveness of immature B cells in spleen. [source] Novel role of nectin: implication in the co-localization of JAM-A and claudin-1 at the same cell,cell adhesion membrane domainGENES TO CELLS, Issue 8 2008Kaori Kuramitsu Tight junctions (TJs) are formed at the apical side of adherens junctions (AJs) in epithelial cells. Major cell adhesion molecules (CAMs) at TJs are JAM and claudin, whereas major CAMs at AJs are nectin and cadherin. We previously showed that nectin initially forms cell,cell adhesion and then recruits cadherin to the nectin-based cell,cell adhesion sites to form AJs, followed by the recruitment of JAM and claudin to the apical side of AJs to form TJs. We investigated the roles of nectin in the formation of TJs by expressing various combinations of CAMs in L fibroblasts with no TJs or AJs. Co-expression of one of the AJ CAMs and one of the TJ CAMs formed two separate cell,cell adhesion membrane domains (CAMDs). Co-expression of nectin-3 and E-cadherin formed the same CAMD, but co-expression of JAM-A and claudin-1 did not form the same CAMD. Co-expression of JAM-A and claudin-1 with nectin-3, but not E-cadherin, made them form the same CAMD, which was separated from the nectin-based CAMD. Nectin-3 required afadin, a nectin- and F-actin-binding protein, for this ability. In conclusion, nectin plays a novel role in the co-localization of JAM and claudin at the same CAMD. [source] Expression and distribution of ZO-3, a tight junction MAGUK protein, in mouse tissuesGENES TO CELLS, Issue 11 2003Akihito Inoko Background:, Three related MAGUK proteins, ZO-1, ZO-2 and ZO-3, are concentrated at the cytoplasmic surface of tight junctions. However, in contrast to ZO-1/ZO-2, our knowledge of the expression and distribution of ZO-3 is still fragmentary, partly due to a lack of antibodies that specifically distinguish ZO-3 from ZO-1 and ZO-2. Results:, We generated one pAb and one mAb that specifically recognized ZO-3 on Western blotting. The immunofluorescence signals obtained with these antibodies completely disappeared from ZO-1/ZO-2-positive tight junctions in the liver of ZO-3-deficient mice, indicating that the antibodies can be used to localize ZO-3 in various tissues by immunofluorescence microscopy. Immunofluorescence microscopy with these antibodies revealed that ZO-3 was concentrated at tight junctions in various types of epithelium, but not in endothelium or at cadherin-based cell-cell adhesion sites (spot adherens junctions of fibroblasts and intercalated discs of cardiac muscle cells), where ZO-1 and ZO-2 are concentrated. Conclusions:, We conclude that ZO-3 is expressed in a more epithelium-specific manner than ZO-1 and ZO-2. These observations provide for a better understanding of the functions of tight junction-associated MAGUKs. [source] Novel hepatic progenitor cell surface markers in the adult rat liver,HEPATOLOGY, Issue 1 2007Mladen I. Yovchev Hepatic progenitor/oval cells appear in injured livers when hepatocyte proliferation is impaired. These cells can differentiate into hepatocytes and cholangiocytes and could be useful for cell and gene therapy applications. In this work, we studied progenitor/oval cell surface markers in the liver of rats subjected to 2-acetylaminofluorene treatment followed by partial hepatectomy (2-AAF/PH) by using rat genome 230 2.0 Array chips and subsequent RT-PCR, immunofluorescent (IF), immunohistochemical (IHC) and in situ hybridization (ISH) analyses. We also studied expression of the identified novel cell surface markers in fetal rat liver progenitor cells and FAO-1 hepatoma cells. Novel cell surface markers in adult progenitor cells included tight junction proteins, integrins, cadherins, cell adhesion molecules, receptors, membrane channels and other transmembrane proteins. From the panel of 21 cell surface markers, 9 were overexpressed in fetal progenitor cells, 6 in FAO-1 cells and 6 are unique for the adult progenitors (CD133, claudin-7, cadherin 22, mucin-1, ros-1, Gabrp). The specificity of progenitor/oval cell surface markers was confirmed by ISH and double IF analyses. Moreover, study of progenitor cells purified with Ep-CAM antibodies from D-galactosamine injured rat liver, a noncarcinogenic model of progenitor cell activation, verified that progenitor cells expressed these markers. Conclusion: We identified novel cell surface markers specific for hepatic progenitor/oval cells, which offers powerful tool for their identification, isolation and studies of their physiology and pathophysiology. Our studies also reveal the mesenchymal/epithelial phenotype of these cells and the existence of species diversity in the hepatic progenitor cell identity. (HEPATOLOGY 2007;45:139,149.) [source] Cadherin-8 and N-cadherin differentially regulate pre- and postsynaptic development of the hippocampal mossy fiber pathwayHIPPOCAMPUS, Issue 4 2008Iddil H. Bekirov Abstract Cells sort into regions and groups in part by their selective surface expression of particular classic cadherins during development. In the nervous system, cadherin-based sorting can define axon tracts, restrict axonal and dendritic arbors to particular regions or layers, and may encode certain aspects of synapse specificity. The underlying model has been that afferents and their targets hold in common the expression of a particular cadherin, thereby providing a recognition code of homophilic cadherin binding. However, most neurons express multiple cadherins, and it is not clear whether multiple cadherins all act similarly in shaping neural circuitry. Here we asked how two such cadherins, cadherin-8 and N-cadherin, influence the guidance and differentiation of hippocampal mossy fibers. Using organotypic hippocampal cultures, we find that cadherin-8 regulates mossy fiber fasciculation and targeting, but has little effect on CA3 dendrites. In contrast, N-cadherin regulates mossy fiber fasciculation, but has little impact on axonal growth and targeting. However, N-cadherin is essential for CA3 dendrite arborization. Both cadherins are required for formation of proper numbers of presynaptic terminals. Mechanistically, such differential actions of these two cadherins could, in theory, reflect coupling to distinct intracellular binding partners. However, we find that both cadherins bind ,-catenin in dentate gyrus (DG). This suggests that cadherins may engage different intracellular signaling cascades downstream of ,-catenin, coopt different extracellular binding partners, or target distinct subcellular domains. Together our findings demonstrate that cadherin-8 and N-cadherin are critical for generating the mossy fiber pathway, but that each contributes differentially to afferent and target differentiation, thereby complementing one another in the assembly of a synaptic circuit. © 2007 Wiley-Liss, Inc. [source] Immunohistochemical and molecular genetic profiling of acquired cystic disease-associated renal cell carcinomaHISTOPATHOLOGY, Issue 2 2009Chin-Chen Pan Aims:, Acquired cystic disease-associated renal cell carcinoma (ACD-associated RCC) is a unique neoplasm that specifically develops in the background of acquired cystic disease of the kidney. The aim was to analyse nine ACD-associated RCCs from three patients to determine their immunohistochemical and molecular characteristics using immunohistochemistry, comparative genomic hybridization (CGH) and fluorescence in situ hybridization (FISH). Methods and results:, ACD-associated RCC preferentially expressed proximal nephron phenotype (CD10+/RCC marker+/,-methylacyl-CoA racemase+/glutathione S-transferase-,+/BerEP4+/cytokeratin 7,/E-cadherin,/high-molecular-weight cytokeratin,/MOC31,). CGH combined with FISH demonstrated non-random chromosomal gains clustering on chromosomes 3 (8/9), 7 (6/9), 16 (7/9), 17 (4/9) and Y (5/9). Chromosomal losses were uncommon. The chromosomal aberrations in all multifocal tumours were not identical for the same kidney or for the same patient, indicating a ,field effect' that induces multiple independent clones. Conclusions:, Although the genetic profiles of ACD-associated RCC showed some similarity to those of papillary RCC, ACD-associated RCC distinctly revealed frequent gains on chromosomes 3 and Y. ACD-associated RCC is characterized not only by its particular clinical setting and histology, but also by its unique immunohistochemical and molecular genetic profiles. [source] Co-production of vascular endothelial cadherin and inducible nitric oxide synthase by endothelial cells in periapical granulomaINTERNATIONAL ENDODONTIC JOURNAL, Issue 3 2006S. Hama Abstract Aim, To clarify the mechanisms of inflammatory cell migration in human periapical granulomas by examining vascular endothelial (VE) cadherin and inducible nitric oxide synthase (iNOS)-producing cells. Methodology, Periapical tissues were obtained from patients during endodontic surgery and were divided into two portions. After fixing the tissues with acetone or 4% paraformaldehyde in phosphate-buffered saline, 5- ,m-thick paraffin or cryostat sections were prepared, respectively. The paraffin sections of the inflamed tissues were evaluated histologically with haematoxylin,eosin stains. Cryostat sections of the tissue, diagnosed as periapical granulomas, were then examined by either immunohistochemistry using anti-human VE-cadherin or iNOS antibodies (Abs) for the characterization of infiltrating cells. In addition, co-localization of VE-cadherin and iNOS production was also analysed by two-colour immunofluorescence image analysis. Results, Endothelial cells were strongly stained with iNOS Abs. Macrophages, lymphocytes, polymorphonuclear leucocytes and fibroblasts also exhibited iNOS production. These iNOS-positive cells accumulated around the blood vessels. On the other hand, VE-cadherin production was exhibited in only endothelial cells. Two-colour immunofluorescence image analysis using VE-cadherin and iNOS Abs demonstrated that iNOS-producing endothelial cells also showed VE-cadherin production. Conclusions, Vascular endothelial-cadherin produced by endothelial cells could be regulated by iNOS-producing cells in periapical granulomas and might play a pivotal role in vascular permeability. [source] Endothelial barriers: from hypothetical pores to membrane proteins*JOURNAL OF ANATOMY, Issue 6 2002J. A. Firth Abstract The anatomical counterpart of the physiologically defined small pore system of capillary endothelia has proved difficult to establish. In non-brain continuous capillaries, the contributions of caveolar and transmembrane pathways are likely to be small and paracellular clefts are probably the dominant routes. Analogy with epithelial paracellular pathways suggests that tight junctions may be the most restrictive elements. However, structural features of tight junction-based models are incompatible with physiological data; it is more likely that the tight junction acts as a shutter limiting the available cleft area. Proposed molecular sieves elsewhere in the paracellular pathway include the glycocalyx and the cadherin-based complexes of the adherens junctions. The molecular architecture of tight junctions and adherens junctions is moderately well defined in terms of molecular species, and there are differences at both sites between the endothelial and epithelial spectra of protein expression. However, definition of the size-restricting pore remains elusive and may require structural biology approaches to the spatial arrangements and interactions of the membrane molecular complexes surrounding the endothelial paracellular clefts. [source] A Dominant Negative Cadherin Inhibits Osteoblast Differentiation,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 12 2000Su-Li Cheng Abstract We have previously indicated that human osteoblasts express a repertoire of cadherins and that perturbation of cadherin-mediated cell-cell interaction reduces bone morphogenetic protein 2 (BMP-2) stimulation of alkaline phosphatase activity. To test whether inhibition of cadherin function interferes with osteoblast function, we expressed a truncated N-cadherin mutant (NCad,C) with dominant negative action in MC3T3-E1 osteoblastic cells. In stably transfected clones, calcium-dependent cell-cell adhesion was decreased by 50%. Analysis of matrix protein expression during a 4-week culture period revealed that bone sialoprotein, osteocalcin, and type I collagen were substantially inhibited with time in culture, whereas osteopontin transiently increased. Basal alkaline phosphatase activity declined in cells expressing NCad,C, relative to control cells, after 3 weeks in culture, and their cell proliferation rate was reduced moderately (17%). Finally,45Ca uptake, an index of matrix mineralization, was decreased by 35% in NCad,C-expressing cells compared with control cultures after 4 weeks in medium containing ascorbic acid and ,-glycerophosphate. Similarly, BMP-2 stimulation of alkaline phosphatase activity and bone sialoprotein and osteopontin expression also were curtailed in NCad,C cells. Therefore, expression of dominant negative cadherin results in decreased cell-cell adhesion associated with altered bone matrix protein expression and decreased matrix mineralization. Cadherin-mediated cell-cell adhesion is involved in regulating the function of bone-forming cells. [source] Membrane potential and endocytic activity control disintegration of cell,cell adhesion and cell fusion in vinculin-injected MDBK cellsJOURNAL OF CELLULAR PHYSIOLOGY, Issue 3 2004Riitta Palovuori Cell fusion occurs during fertilization and in the formation of organs such as muscles, placenta, and bones. We have developed an experimental model for epithelial cell fusion which permits analysis of the processes during junction disintegration and formation of polykaryons (Palovuori and Eskelinen [2000] Eur. J. Cell. Biol. 79: 961,974). In the present work, we analyzed the process in detail. Cell fusion was achieved by microinjecting into the cytoplasm of kidney epithelial Madin-Darby bovine kidney (MDBK) cells TAMRA-tagged vinculin, which incorporated into lateral membranes, focal adhesions and nucleus, and, prior fusion, induced internalization of actin, cadherin and plakoglobin to small clusters in cytoplasm. Injected vinculin was still visible at lateral membranes after removal of junctional proteins indicating that it was tightly associated and perturbed the cell,cell contact sites resulting in membrane fragmentation. Injection of active Rac together with vinculin induced accumulation of cadherin to the membranes, but did not affect vinculin,membrane association. However, it hampered cell fusion probably by supporting adherens junctions. In order to stop endocytosis, we lowered intracellular pH of vinculin-injected cells to 5.5 with the aid of nigericin in KCl buffer. In acidified cells, injected vinculin delineated lateral membranes as thick layers, cadherin remained in situ, and cell fusion was completely inhibited. Since this treatment also leads to cell depolarization, we checked the vinculin incorporation in a KCl solution containing nigericin at neutral pH. In these circumstances, both endogenous and injected vinculin delineated lateral membranes as very thin discontinuous layers, but still fusion was hampered most likely due to perturbation in the initial vinculin,membrane association. We suggest that vinculin might function as a sensor of the environment triggering cell fusion during development in circumstances where membrane potential and local and transient pH gradients play a role. © 2004 Wiley-Liss, Inc. [source] Roles of cell adhesion molecules nectin and nectin-like molecule-5 in the regulation of cell movement and proliferationJOURNAL OF MICROSCOPY, Issue 3 2008H. OGITA Summary In response to chemoattractants, migrating cells form protrusions, such as lamellipodia and filopodia, and structures, such as ruffles over lamellipodia, focal complexes and focal adhesions at leading edges. The formation of these leading edge structures is essential for directional cell movement. Nectin-like molecule-5 (Necl-5) interacts in cis with PDGF receptor and integrin ,v,3, and enhances the activation of signalling molecules associated with these transmembrane proteins, which results in the formation of leading edge structures and enhancement of directional cell movement. When migrating cells come into contact with each other, cell,cell adhesion is initiated, resulting in reduced cell velocity. Necl-5 first interacts in trans with nectin-3. This interaction is transient and induces down-regulation of Necl-5 expression at the cell surface, resulting in reduced cell movement. Cell proliferation is also suppressed by the down-regulation of Necl-5, because the inhibitory effect of Necl-5 on Sprouty2, a negative regulator of the Ras signalling, is diminished. PDGF receptor and integrin ,v,3, which have interacted with Necl-5, then form a complex with nectin, which initiates cell,cell adhesion and recruits cadherin to the nectin-based cell,cell adhesion sites to form stable adherens junctions. The formation of adherens junctions stops cell movement, in part through inactivation of integrin ,v,3 caused by the trans -interaction of nectin. Thus, nectin and Necl-5 play key roles in the regulation of cell movement and proliferation. [source] Hyperosmotic mannitol induces Src kinase-dependent phosphorylation of ,-catenin in cerebral endothelial cellsJOURNAL OF NEUROSCIENCE RESEARCH, Issue 6 2005Attila Farkas Abstract Mannitol, which is a cell-impermeable and nontoxic polyalcohol, has been shown to be a useful tool for reversible opening of the blood,brain barrier (BBB). Despite successful clinical trials, the molecular mechanism of the mannitol-induced changes in cerebral endothelial cells (CECs) are poorly understood. For our experiments, we used CECs in culture, which were treated with different, clinically relevant concentrations of mannitol. We found that mannitol induced a rapid, concentration-dependent, and reversible tyrosine phosphorylation of a broad range of proteins between 50 and 190 kDa. One of the targets of tyrosine phosphorylation turned out to be the adherens junction protein ,-catenin. Phosphorylation of ,-catenin on tyrosine residues caused its subcellular redistribution and its dissociation from cadherin and ,-catenin as shown by coimmunoprecipitation studies. All these effects could be inhibited by the Src kinase inhibitor PP-1 but not by the Erk inhibitor U0126, the Rho kinase inhibitor Y27632, or the calcium channel blocker verapamil. Because ,-catenin is a key component of the junctional complex, its Src-mediated phpsphorylation may play an important role in the mannitol induced reversible opening of the BBB. © 2005 Wiley-Liss, Inc. [source] Parity is associated with lower cervical E-cadherin expression in postmenopausal womenJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 6 2008Vasileios Sioulas Abstract Aim:, Epithelial cadherin (E-cadherin), a transmembrane glycoprotein involved in calcium-dependent homophilic cell-cell adhesion, is expressed aberrantly during cervical carcinogenesis. E-cadherin expression and putatively implicated predictors in healthy women remain a rather under-investigated area. The objective of this study is to evaluate the possible associations between E-cadherin expression and reproductive/lifestyle factors in cervical epithelial cells from postmenopausal women. Methods:, A total of 105 healthy postmenopausal women (aged 45,68 years old) attending a university menopause clinic were enrolled in this cross-sectional study. Pap smears were derived and E-cadherin immunostaining was evaluated in squamous, glandular and squamous metaplastic cells, using a semi-quantitative method (rating scale: 0,3). Reproductive and lifestyle factors were obtained from patients' chart review. Results:, In squamous cells, women with a history of 0,1 deliveries presented with a higher score vs women with 2,4 deliveries (P = 0.003). Social drinkers and women drinking alcohol daily exhibited a higher E-cadherin immunostaining score in squamous cells vs non-drinkers (0.96 ± 0.72 vs 0.56 ± 0.65, P = 0.004). A higher dietary calcium intake was marginally correlated with a lower staining score in squamous cells (0.94 ± 0.78 for low, 0.71 ± 0.70 for average, 0.45 ± 0.52 for high consumption, P = 0.073). Conclusions:, E-cadherin expression seems to be associated with reproductive history and lifestyle habits in squamous cervical cells from healthy postmenopausal women. E-cadherin might participate in the molecular mechanisms underlying the role of parity as a risk factor for cervical cancer. [source] Upregulation of ,-Catenin Levels in Superior Frontal Cortex of Chronic AlcoholicsALCOHOLISM, Issue 6 2008Ali M. Al-Housseini Background:, Chronic and excessive alcohol misuse results in neuroadaptive changes in the brain. The complex nature of behavioral, psychological, emotional, and neuropathological characteristics associated with alcoholism is likely a reflection of the network of proteins that are affected by alcohol-induced gene expression patterns in specific brain regions. At the molecular level, however, knowledge remains limited regarding alterations in protein expression levels affected by chronic alcohol abuse. Thus, novel techniques that allow a comprehensive assessment of this complexity will enable the simultaneous assessment of changes across a group of proteins in the relevant neural circuitry. Methods:, A proteomics analysis was performed using antibody microarrays to determine differential protein levels in superior frontal cortices between chronic alcoholics and age- and gender-matched control subjects. Seventeen proteins related to the catenin signaling pathway were analyzed, including ,-, ,-, and ,-catenins, their upstream activators cadherin-3 (type I cadherin) and cadherin-5 (type II cadherin), and 5 cytoplasmic regulators c-Src, CK1,, GSK-3,, PP2A-C,, and APC, as well as the nuclear complex partner of ,-catenin CBP and 2 downstream genes Myc and cyclin D1. ILK, G,1, G,1, and G,2, which are activity regulators of GSK-3,, were also analyzed. Results:, Both ,- and ,-catenin showed significantly increased levels, while ,-catenin did not change significantly, in chronic alcoholics. In addition, the level of the ,-catenin downstream gene product Myc was significantly increased. Average levels of the catenin regulators c-Src, CK1,, and APC were also increased in chronic alcoholics, but the changes were not statistically significant. Conclusion:, Chronic and excessive alcohol consumption leads to an upregulation of ,- and ,-catenin levels, which in turn increase downstream gene expressions such as Myc that is controlled by ,-catenin signaling. This study showed that the ,-catenin signal transduction pathway was upregulated by chronic alcohol abuse, and prompts further investigation of mechanisms underlying the upregulation of ,- and ,-catenins in alcoholism, which may have considerable pathogenic and therapeutic relevance. [source] Pores in the Sieve and Channels in the Wall: Control of Paracellular Permeability by Junctional Proteins in Endothelial CellsMICROCIRCULATION, Issue 3 2001GIANFRANCO BAZZONI ABSTRACT Exchange of solutes and ions between the luminal and abluminal compartments of the circulation is critically dependent on the barrier properties of the vascular endothelium. Transport of solutes and fluids occurs along the transcellular and paracellular pathways that are mediated by intracellular vesicles and intercellular junctions, respectively. Although the ability of endothelial cells to dynamically regulate permeability has long been recognized, the precise mechanism and the signaling pathways involved have not been fully elucidated. Finally, current definition of the complex molecular composition of intercellular junctions is expected to explain the difference in permeability between diverse segments of the circulation and possibly to highlight the existence of specific junctional channels. The properties of junctional adhesion molecule-1 (JAM-1) and vascular endothelial cadherin (VE-cadherin), two transmembrane components of interendothelial junctions, are described in detail. [source] Astroblastoma: Immunohistochemical and ultrastructural study of distinctive epithelial and probable tanycytic differentiationNEUROPATHOLOGY, Issue 1 2006Toshihiko Kubota We report the clinicopathological findings of astroblastoma found in an 8-year-old girl who was subsequently treated for 11 years. The primary superficially circumscribed tumor was located in the frontoparietal lobe, while the recurrent and the second recurrent tumor were restricted to the same region 11 years later. The tumors obtained on these three occasions showed fundamentally the same histological, immunohistochemical and fine structural features. They exhibited astrocytic as well as ependymal tanycytic features with apparent epithelial cell lineage. The tumor cells showed typical features of astroblastoma comprising prominent perivascular pseudorosettes with remarkable vascular sclerosis. The immunohistochemical study revealed intensive positivity of GFAP, vimentin, epithelial membrane antigen (EMA), cytokeratin, connexin 26 and 32, desmocollin 1 and neuronal cadherin. The fine structure revealed divergent types of junctional complexes, some of which were connected with tonofilament bundles. Numerous microvilli protruded and basal lamina abutted on the tumor cell surface. We report these unique histological features, and stress that astroblastoma should be categorized as a specific type of neuroepithelial tumor. [source] Expression of E-cadherin and catenins in meningioma: Ubiquitous expression and its irrelevance to malignancyPATHOLOGY INTERNATIONAL, Issue 1 2005Shio Shimada The expression of cell adhesion molecules in 107 meningiomas was analyzed with immunohistochemical methods using antibodies to epithelial (E)-cadherin and catenins (,, , and ,). According to the provided World Health Organization (WHO) grading, 84, 18 and five cases were classified as grade I, II and III, respectively. In addition, hemangioblastoma (15 cases) and hemangiopericytoma (four cases) were also evaluated. In most meningiomas, E-cadherin, ,- and ,-catenins were expressed along the cell membrane or inside the cytoplasm. The tumor cells constituting whorls and glandular structures of secretory type showed a strong immunoreactivity. ,-Catenin expression tended to be weak and infrequent in fibrous meningiomas, while other types exhibited diffuse stainings. Even in meningiomas of more than grade II, the expressions of cell adhesion molecules were detected in all cases. Hemangiopericytoma was positive for ,- and ,-catenins, and hemangioblastomas were positive for ,-catenin alone, which was distinct from the expression pattern in meningiomas. Quantitatively, there were no correlations between the histological variants, Ki-67 indexes, or grades of meningiomas and the immunoreactive scores except for ,-catenin scores of fibrous meningiomas. The present study demonstrates that cell adhesion molecules are ubiquitously expressed in all variants of meningioma and may be involved in the tumor morphogenesis. This result suggests that the expression of cell adhesion molecules is not a reliable indicator of malignancy in meningiomas. The present study also suggests that these markers may be useful for the differential diagnosis of meningioma. [source] Single nucleotide polymorphisms in the cadherin 23 (CDH23) gene in Polish workers exposed to industrial noise,AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 4 2008Mariola Sliwinska-Kowalska Single nucleotide polymorphisms (SNPs) are the most frequent type of variation in the human genome and may underlie differential susceptibility to common genetic diseases. A candidate gene for susceptibility to noise-induced hearing loss (NIHL) is Cadherin 23 (CDH23). This study aimed to analyze genetic variation in the CDH23 gene in a group of 10 individuals derived from a cohort of 949 workers exposed to noise, and consisted of five persons from each of the resistant and susceptible extremes. DNA samples were collected and the coding exons of CDH23 were sequenced. We identified a total of 35 SNPs: 11 amino acid substitutions, 8 silent nucleotide changes, and 16 substitutions in intervening sequences. Ten of the 11 amino acid substitutions were previously shown also to segregate in a Cuban population. The nonsynonymous SNPs localized to the part of the gene encoding the extracellular domain of Cadherin 23, in particular ectodomains 5, 13, 14, 15, 16, 17, 19, and 22. One amino acid change occurred at a conserved position in ectodomain 5. Our results provide a framework for future study of polymorphisms in CDH23 as risk factor for NIHL. Am. J. Hum. Biol., 2008. Published 2008 Wiley-Liss, Inc. [source] Plasticity of Cadherin,Catenin Expression in the Melanocyte LineagePIGMENT CELL & MELANOMA RESEARCH, Issue 4 2000ALICE JOUNEAU Cadherins are calcium-dependent cell adhesion receptors with strong morphoregulatory functions. To mediate functional adhesion, cadherins must interact with actin cytoskeleton. Catenins are cytoplasmic proteins that mediate the interactions between cadherins and the cytoskeleton. In addition to their role in cell,cell adhesion, catenins also participate in signaling pathways that regulate cell growth and differentiation. Cadherins and catenins appear to be involved in melanocyte development and transformation. Here, we investigated the function of cadherin,catenin complexes in the normal development and transformation of melanocytes by studying the patterns of expression of the cell,cell adhesion molecules, E-, N- and P-cadherin, and the expression of their cytoplasmic partners, ,-, ,- and ,-catenin, during murine development. Similar analyses were performed in vitro using murine melanoblast, melanocyte, and melanoma cell lines in the presence and absence of keratinocytes, the cells with which melanocytes interact in vivo. Overall, the results suggest that the expression of cadherins and catenins is very plastic and depends on their environment as well as the transformation status of the cells. This plasticity is important in fundamental cellular mechanisms associated with normal and pathological ontogenesis, as well as with tumorigenesis. [source] Differential protein expression on the cell surface of colorectal cancer cells associated to tumor metastasisPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 5 2010Jose Luis Luque-García Abstract Progression to metastasis is the critical point in colorectal cancer (CRC) survival. However, the proteome associated to CRC metastasis is very poorly understood at the moment. In this study, we used stable isotope labeling by amino acids in cell culture to compare two CRC cell lines: KM12C and KM12SM, representing poorly versus highly metastatic potential, to find and quantify the differences in protein expression, mostly at the cell surface level. After biotinylation followed by affinity purification, membrane proteins were separated by SDS-PAGE and analyzed using nanoflow LC-ESI-LTQ. A total of 291 membrane and membrane-associated proteins were identified with a p value<0.01, from which 60 proteins were found to be differentially expressed by more than 1.5-fold. We identified a number of cell signaling, CDs, integrins and other cell adhesion molecules (cadherin 17, junction plakoglobin (JUP)) among the most deregulated proteins. They were validated by Western blot, confocal microscopy and flow cytometry analysis. Immunohistochemical analysis of paired tumoral samples confirmed that these differentially expressed proteins were also altered in human tumoral tissues. A good correlation with a major abundance in late tumor stages was observed for JUP and 17-,-hydroxysteroid dehydrogenase type 8 (HSD17B8). Moreover, the combined increase in JUP, occludin and F11 receptor expression together with cadherin 17 expression could suggest a reversion to a more epithelial phenotype in highly metastatic cells. Relevant changes were observed also at the metabolic level in the pentose phosphate pathway and several amino acid transporters. In summary, the identified proteins provide us with a better understanding of the events involved in liver colonization and CRC metastasis. [source] Establishment of cadherin-based intercellular junctions in the dermal papilla of the developing hair follicleTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 2 2003Daisuke Nanba Abstract During hair follicle development, mesenchymal cells aggregate to form the dermal papilla with hair-inducing activity. However, the cellular mechanisms underlying the aggregative behavior of dermal papilla cells are less known. The present study demonstrates that cadherin-based intercellular junctions interconnect dermal papilla cells in developing hair follicles of mice. It is shown that as mesenchymal cells aggregate to be surrounded by epithelium in developing hair follicles, cadherin-11 comes to exhibit the dotted patterns of distribution. The appearance of the dot-like distribution of the molecule is concomitant with the formation of intercellular junctions in the mesenchymal aggregate, which make a tightly packed population of cells with little extracellular space. At later stages of the development, although extracellular space reappears in the dermal papilla, the cells remain interconnected by well-developed intercellular junctions, where cadherin-11 as well as ,-catenin is localized. Taking into consideration the normal hair development in cadherin-11 mutant mice, it might be that multiple cadherins are responsible for the establishment of intercellular junctions in the dermal papilla and serve to maintain the aggregative behavior of the cells. Anat Rec Part A 270A:97,102, 2003. © 2003 Wiley-Liss, Inc. [source] Immunohistochemical comparison of ,-catenin expression by human normal epidermis and epidermal tumorsTHE JOURNAL OF DERMATOLOGY, Issue 11 2007Keiko FUKUMARU ABSTRACT ,-Catenin, a cytoplasmic protein that binds directly to the intracellular domain of cadherin, controls various functions such as cell adhesion. In many human carcinomas, E-cadherin-mediated cell,cell adhesion is lost or disturbed and related to metastasis. The purpose of this study was to compare the expression of ,-catenin in the normal epidermal keratinocytes and samples from cutaneous benign and malignant epidermal tumors in 140 patients. Our study population consisted of 140 patients with benign or malignant epidermal tumors. Using immunohistochemical methods, we compared the expression of ,-catenin in their normal epidermal keratinocytes, and in samples from 61 benign (seborrheic keratosis, n = 33; verruca vulgaris, n = 14; keratoacanthoma, n = 14), and 79 malignant (Bowen's disease, n = 18; basal cell carcinoma, n = 33; squamous cell carcinoma, n = 28) epidermal tumors. ,-Catenin was found to be expressed in the cell membrane of normal keratinocytes. Compared to other cell components of the normal epidermis, basal cells showed the strongest ,-catenin expression in all 140 patients. While absent in three of 61 benign tumors, compared to normal basal cells, the expression of ,-catenin in the other 58 tumors was not significantly different; it was reduced in 71 of 79 malignant tumors (P < 0.0001). In Bowen's disease, the expression of ,-catenin on the tumor cell membrane was reduced, however, strong expression was seen in the nuclei and cytoplasm. Our results suggest that ,-catenin expression on the membrane of keratinocytes is associated with the differentiation of normal keratinocytes but not with their stage of differentiation, nor with the proliferation ability of epidermal tumor cells. [source] | ||||||||||||||||||||||||||||||||||