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Sample records for junction protein e-cadherin

  1. PLEKHA7 is an adherens junction protein with a tissue distribution and subcellular localization distinct from ZO-1 and E-cadherin.

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    Pamela Pulimeno

    Full Text Available The pleckstrin-homology-domain-containing protein PLEKHA7 was recently identified as a protein linking the E-cadherin-p120 ctn complex to the microtubule cytoskeleton. Here we characterize the expression, tissue distribution and subcellular localization of PLEKHA7 by immunoblotting, immunofluorescence microscopy, immunoelectron microscopy, and northern blotting in mammalian tissues. Anti-PLEKHA7 antibodies label the junctional regions of cultured kidney epithelial cells by immunofluorescence microscopy, and major polypeptides of M(r approximately 135 kDa and approximately 145 kDa by immunoblotting of lysates of cells and tissues. Two PLEKHA7 transcripts ( approximately 5.5 kb and approximately 6.5 kb are detected in epithelial tissues. PLEKHA7 is detected at epithelial junctions in sections of kidney, liver, pancreas, intestine, retina, and cornea, and its tissue distribution and subcellular localization are distinct from ZO-1. For example, PLEKHA7 is not detected within kidney glomeruli. Similarly to E-cadherin, p120 ctn, beta-catenin and alpha-catenin, PLEKHA7 is concentrated in the apical junctional belt, but unlike these adherens junction markers, and similarly to afadin, PLEKHA7 is not localized along the lateral region of polarized epithelial cells. Immunoelectron microscopy definitively establishes that PLEKHA7 is localized at the adherens junctions in colonic epithelial cells, at a mean distance of 28 nm from the plasma membrane. In summary, we show that PLEKHA7 is a cytoplasmic component of the epithelial adherens junction belt, with a subcellular localization and tissue distribution that is distinct from that of ZO-1 and most AJ proteins, and we provide the first description of its distribution and localization in several tissues.

  2. Restoration of E-cadherin Cell-Cell Junctions Requires Both Expression of E-cadherin and Suppression of ERK MAP Kinase Activation in Ras-Transformed Breast Epithelial Cells

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    Quanwen Li

    2008-12-01

    Full Text Available E-cadherin is a main component of the cell-cell adhesion junctions that play a principal role in maintaining normal breast epithelial cell morphology. Breast and other cancers that have up-regulated activity of Ras are often found to have down-regulated or mislocalized E-cadherin expression. Disruption of E-cadherin junctions and consequent gain of cell motility contribute to the process known as epithelial-to-mesenchymal transition (EMT. Enforced expression of E-cadherin or inhibition of Ras-signal transduction pathway has been shown to be effective in causing reversion of EMT in several oncogene-transformed and cancer-derived cell lines. In this study, we investigated MCF10A human breast epithelial cells and derivatives that were transformed with either activated H-Ras or N-Ras to test for the reversion of EMT by inhibition of Ras-driven signaling pathways. Our results demonstrated that inhibition of mitogen-activated protein kinase (MAPK kinase, but not PI3-kinase, Rac, or myosin light chain kinase, was able to completely restore E-cadherin cell-cell junctions and epithelial morphology in cell lines with moderate H-Ras expression. In MCF10A cells transformed by a high-level expression of activated H-Ras or N-Ras, restoration of E-cadherin junction required both the enforced reexpression of E-cadherin and suppression of MAPK kinase. Enforced expression of E-cadherin alone did not induce reversion from the mesenchymal phenotype. Our results suggest that Ras transformation has at least two independent actions to disrupt E-cadherin junctions, with effects to cause both mislocalization of E-cadherin away from the cell surface and profound decrease in the expression of E-cadherin.

  3. The Scribble polarity protein stabilizes E-cadherin/p120-catenin binding and blocks retrieval of E-cadherin to the Golgi.

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    Madhura Lohia

    Full Text Available Several polarity proteins, including Scribble (Scrb have been implicated in control of vesicle traffic, and in particular the endocytosis of E-cadherin, but through unknown mechanisms. We now show that depletion of Scrb enhances endocytosis of E-cadherin by weakening the E-cadherin-p120catenin interaction. Unexpectedly, however, the internalized E-cadherin is not degraded but accumulates in the Golgi apparatus. Silencing p120-catenin causes degradation of E-cadherin in lysosomes, but degradation is blocked by the co-depletion of Scrb, which diverts the internalized E-cadherin to the Golgi. Loss of Scrb also enhances E-cadherin binding to retromer components, and retromer is required for Golgi accumulation of Scrb, and E-cadherin stability. These data identify a novel and unanticipated function for Scrb in blocking retromer-mediated diversion of E-cadherin to the Golgi. They provide evidence that polarity proteins can modify the intracellular itinerary for endocytosed membrane proteins.

  4. JNK signaling regulates E-cadherin junctions in germline cysts and determines primordial follicle formation in mice.

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    Niu, Wanbao; Wang, Ye; Wang, Zhengpin; Xin, Qiliang; Wang, Yijing; Feng, Lizhao; Zhao, Lihua; Wen, Jia; Zhang, Hua; Wang, Chao; Xia, Guoliang

    2016-05-15

    Physiologically, the size of the primordial follicle pool determines the reproductive lifespan of female mammals, while its establishment largely depends on a process of germline cyst breakdown during the perinatal period. The mechanisms regulating this process are poorly understood. Here we demonstrate that c-Jun amino-terminal kinase (JNK) signaling is crucial for germline cyst breakdown and primordial follicle formation. JNK was specifically localized in oocytes and its activity increased as germline cyst breakdown progressed. Importantly, disruption of JNK signaling with a specific inhibitor (SP600125) or knockdown technology (Lenti-JNK-shRNAs) resulted in significantly suppressed cyst breakdown and primordial follicle formation in cultured mouse ovaries. Our results show that E-cadherin is intensely expressed in germline cysts, and that its decline is necessary for oocyte release from the cyst. However, inhibition of JNK signaling leads to aberrantly enhanced localization of E-cadherin at oocyte-oocyte contact sites. WNT4 expression is upregulated after SP600125 treatment. Additionally, similar to the effect of SP600125 treatment, WNT4 overexpression delays cyst breakdown and is accompanied by abnormal E-cadherin expression patterns. In conclusion, our results suggest that JNK signaling, which is inversely correlated with WNT4, plays an important role in perinatal germline cyst breakdown and primordial follicle formation by regulating E-cadherin junctions between oocytes in mouse ovaries. © 2016. Published by The Company of Biologists Ltd.

  5. Intravital FRAP Imaging using an E-cadherin-GFP Mouse Reveals Disease- and Drug-Dependent Dynamic Regulation of Cell-Cell Junctions in Live Tissue

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    Zahra Erami

    2016-01-01

    Full Text Available E-cadherin-mediated cell-cell junctions play a prominent role in maintaining the epithelial architecture. The disruption or deregulation of these adhesions in cancer can lead to the collapse of tumor epithelia that precedes invasion and subsequent metastasis. Here we generated an E-cadherin-GFP mouse that enables intravital photobleaching and quantification of E-cadherin mobility in live tissue without affecting normal biology. We demonstrate the broad applications of this mouse by examining E-cadherin regulation in multiple tissues, including mammary, brain, liver, and kidney tissue, while specifically monitoring E-cadherin mobility during disease progression in the pancreas. We assess E-cadherin stability in native pancreatic tissue upon genetic manipulation involving Kras and p53 or in response to anti-invasive drug treatment and gain insights into the dynamic remodeling of E-cadherin during in situ cancer progression. FRAP in the E-cadherin-GFP mouse, therefore, promises to be a valuable tool to fundamentally expand our understanding of E-cadherin-mediated events in native microenvironments.

  6. Intravital FRAP Imaging using an E-cadherin-GFP Mouse Reveals Disease- and Drug-Dependent Dynamic Regulation of Cell-Cell Junctions in Live Tissue

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    Erami, Zahra; Herrmann, David; Warren, Sean C.; Nobis, Max; McGhee, Ewan J.; Lucas, Morghan C.; Leung, Wilfred; Reischmann, Nadine; Mrowinska, Agata; Schwarz, Juliane P.; Kadir, Shereen; Conway, James R.W.; Vennin, Claire; Karim, Saadia A.; Campbell, Andrew D.; Gallego-Ortega, David; Magenau, Astrid; Murphy, Kendelle J.; Ridgway, Rachel A.; Law, Andrew M.; Walters, Stacey N.; Grey, Shane T.; Croucher, David R.; Zhang, Lei; Herzog, Herbert; Hardeman, Edna C.; Gunning, Peter W.; Ormandy, Christopher J.; Evans, T.R. Jeffry; Strathdee, Douglas; Sansom, Owen J.; Morton, Jennifer P.; Anderson, Kurt I.; Timpson, Paul

    2015-01-01

    Summary E-cadherin-mediated cell-cell junctions play a prominent role in maintaining the epithelial architecture. The disruption or deregulation of these adhesions in cancer can lead to the collapse of tumor epithelia that precedes invasion and subsequent metastasis. Here we generated an E-cadherin-GFP mouse that enables intravital photobleaching and quantification of E-cadherin mobility in live tissue without affecting normal biology. We demonstrate the broad applications of this mouse by examining E-cadherin regulation in multiple tissues, including mammary, brain, liver, and kidney tissue, while specifically monitoring E-cadherin mobility during disease progression in the pancreas. We assess E-cadherin stability in native pancreatic tissue upon genetic manipulation involving Kras and p53 or in response to anti-invasive drug treatment and gain insights into the dynamic remodeling of E-cadherin during in situ cancer progression. FRAP in the E-cadherin-GFP mouse, therefore, promises to be a valuable tool to fundamentally expand our understanding of E-cadherin-mediated events in native microenvironments. PMID:26725115

  7. Connexins, E-cadherin, Claudin-7 and β-catenin transiently form junctional nexuses during the post-natal mammary gland development.

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    Dianati, Elham; Poiraud, Jérémy; Weber-Ouellette, Anne; Plante, Isabelle

    2016-08-01

    Gap junctions are intercellular channels made of connexins (Cxs) that allow direct communication between adjacent cells. Modulation of Cxs has been associated with abnormal development and function of the mammary gland and breast cancer. However, the mechanisms underlying their expression during normal mammary gland are not yet known. Cxs interact with components of tight and adherens junctions. Thus, we hypothesized that the expression levels of Cxs vary during mammary gland development and are regulated through stage-dependent interactions with members of the tight and adherens junctions. Our specific objectives were to: 1) determine the expression of Cxs and tight and adherens junction proteins throughout development and 2) characterize Cxs interactions with components of tight and adherens junctions. Murine mammary glands were sampled at various developmental stages (pre-pubescent to post-weaning). RT-qPCR and western-blot analyses demonstrated differential expression patterns for all gap (Cx43, Cx32, Cx26, Cx30), tight (Claudin-1, -3, -4, -7) and adherens (β-catenin, E- and P-cadherins) junctions throughout development. Interestingly, co-immunoprecipitation demonstrated interactions between these different types of junctions. Cx30 interacted with Cx26 just at the late pregnancy stage. While Cx43 showed a persistent interaction with β-catenin from virginity to post-weaning, its interactions with E-cadherin and Claudin-7 were transient. Cx32 interacted with Cx26, E-cadherin and β-catenin during lactation. Immunofluorescence results confirmed the existence of a junctional nexus that remodeled during mammary gland development. Together, our results confirm that the expression levels of Cxs vary concomitantly and that Cxs form junctional nexuses with tight and adherens junctions, suggesting the existence of common regulatory pathways.

  8. The Postnatal Accumulation of Junctional E-cadherin Is Inversely Correlated with the Capacity for Supporting Cells to Convert Directly into Sensory Hair Cells in Mammalian Balance Organs

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    Collado, Maria Sol; Thiede, Benjamin R.; Baker, Wendy; Askew, Charles; Igbani, Lisa M.; Corwin, Jeffrey T.

    2011-01-01

    Mammals experience permanent impairments from hair cell (HC) losses, but birds and other non-mammals quickly recover hearing and balance senses after supporting cells (SCs) give rise to replacement HCs. Avian HC epithelia express little or no E-cadherin, and differences in the thickness of F-actin belts at SC junctions strongly correlate with different species’ capacities for HC replacement, so we investigated junctional cadherins in human and murine ears. We found strong E-cadherin expression at SC-SC junctions that increases >6-fold postnatally in mice. When we cultured utricles from young mice with γ-secretase inhibitors (GSIs), striolar SCs completely internalized their E-cadherin, without affecting N-cadherin. Hes and Hey expression also decreased and the SCs began to express Atoh1. After 48 h, those SCs expressed myosins VI and VIIA, and by 72 h they developed hair bundles. However, some scattered striolar SCs retained E-cadherin and the SC phenotype. In extrastriolar regions the vast majority of SCs also retained E-cadherin and failed to convert into HCs even after long GSI treatments. Microscopic measurements revealed that the junctions between extrastriolar SCs were more developed than those between striolar SCs. In GSI-treated utricles as old as P12, differentiated striolar SCs converted into HCs, but such responses declined with age and ceased by P16. Thus, temporal and spatial differences in postnatal SC-to-HC phenotype conversion capacity are linked to the structural attributes of E-cadherin containing SC junctions in mammals, which differ substantially from their counterparts in non-mammalian vertebrates that readily recover from hearing and balance deficits through hair cell regeneration. PMID:21849546

  9. The postnatal accumulation of junctional E-cadherin is inversely correlated with the capacity for supporting cells to convert directly into sensory hair cells in mammalian balance organs.

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    Collado, Maria Sol; Thiede, Benjamin R; Baker, Wendy; Askew, Charles; Igbani, Lisa M; Corwin, Jeffrey T

    2011-08-17

    Mammals experience permanent impairments from hair cell (HC) losses, but birds and other non-mammals quickly recover hearing and balance senses after supporting cells (SCs) give rise to replacement HCs. Avian HC epithelia express little or no E-cadherin, and differences in the thickness of F-actin belts at SC junctions strongly correlate with different species' capacities for HC replacement, so we investigated junctional cadherins in human and murine ears. We found strong E-cadherin expression at SC-SC junctions that increases more than sixfold postnatally in mice. When we cultured utricles from young mice with γ-secretase inhibitors (GSIs), striolar SCs completely internalized their E-cadherin, without affecting N-cadherin. Hes and Hey expression also decreased and the SCs began to express Atoh1. After 48 h, those SCs expressed myosins VI and VIIA, and by 72 h, they developed hair bundles. However, some scattered striolar SCs retained E-cadherin and the SC phenotype. In extrastriolar regions, the vast majority of SCs also retained E-cadherin and failed to convert into HCs even after long GSI treatments. Microscopic measurements revealed that the junctions between extrastriolar SCs were more developed than those between striolar SCs. In GSI-treated utricles as old as P12, differentiated striolar SCs converted into HCs, but such responses declined with age and ceased by P16. Thus, temporal and spatial differences in postnatal SC-to-HC phenotype conversion capacity are linked to the structural attributes of E-cadherin containing SC junctions in mammals, which differ substantially from their counterparts in non-mammalian vertebrates that readily recover from hearing and balance deficits through hair cell regeneration.

  10. Clinicopathological significance of SIRT1 and p300/CBP expression in gastroesophageal junction (GEJ) cancer and the correlation with E-cadherin and MLH1.

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    Zhang, Li-Hua; Huang, Qin; Fan, Xiang-Shan; Wu, Hong-Yan; Yang, Jun; Feng, An-Ning

    2013-10-01

    SIRT1 and p300/CBP, which are considered to be essential histone deacetylases and acetyltransferases, are also considered to be relative to tumorigenesis because they modulate the expression of several tumor suppressor genes. Therefore, this study investigated the expression of SIRT1 and p300/CBP in gastroesophageal junction (GEJ) cancer and their correlation with E-cadherin and MLH1 in order to explore the clinicopathological significance of SIRT1 and p300/CBP expression and their possible effects involving E-cadherin and MLH1 expression. Tissue microarray technique and immunohistochemical stains were applied to evaluate the SIRT1, p300/CBP, E-cadherin, and MLH1 expression in 176 GEJ cancer tissues and 32 normal GEJ region tissues. The results showed that the over-expression of SIRT1 was associated with a higher number of metastasis lymph nodes, more advanced staging, and shorter mean survival time. SIRT1 and p300/CBP were negatively and positively correlated with the expression of E-cadherin and MLH1, respectively, in the cancer cases. These results indicated a possible effect of SIRT1 and p300/CBP involved in regulating the expression of E-cadherin and MLH1, thus participating in the tumor progression of GEJ cancer.

  11. Deoxynivanelol and Fumonisin, Alone or in Combination, Induce Changes on Intestinal Junction Complexes and in E-Cadherin Expression

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    Karina Basso

    2013-11-01

    Full Text Available Fusariotoxins such as fumonisin B1 (FB1 and deoxynivalenol (DON cause deleterious effects on the intestine of pigs. The aim of this study was to evaluate the effect of these mycotoxins, alone and in combination, on jejunal explants from piglets, using histological, immunohistochemical and ultrastructural assays. Five 24-day old pigs were used for sampling the explants. Forty-eight explants were sampled from each animal. Explants were incubated for 4 hours in culture medium and medium containing FB1 (100 µM, DON (10 µM and both mycotoxins (100 µM FB1 plus 10 µM DON. Exposure to all treatments induced a significant decrease in the normal intestinal morphology and in the number of goblet cells, which were more severe in explants exposed to DON and both mycotoxins. A significant reduction in villus height occurred in groups treated with DON and with co-contamination. Expression of E-cadherin was significantly reduced in explants exposed to FB1 (40%, DON (93% and FB1 plus DON (100%. The ultrastructural assay showed increased intercellular spaces and no junction complexes on enterocytes exposed to mycotoxins. The present data indicate that FB1 and DON induce changes in cell junction complexes that could contribute to increase paracellular permeability. The ex vivo model was adequate for assessing intestinal toxicity induced by exposure of isolated or associated concentrations of 100 µM of FB1 and 10 µM of DON.

  12. N-glycosylation at Asn residues 554 and 566 of E-cadherin affects cell cycle progression through extracellular signal-regulated protein kinase signaling pathway

    Institute of Scientific and Technical Information of China (English)

    Hongbo Zhao; Xiliang Zha; Lidong Sun; Liying Wang; Zhibin Xu; Feng Zhou; Jianmin Su; Jiawei Jin; Yong Yang; Yali Hu

    2008-01-01

    E-cadherin, which has a widely acknowledged role in mediating calcium-dependent cell-cell adhesion between epithelial cells, also functions as a tumor suppressor. The ectodomain of human E-cadherin contains four potential N-glycosylation sites at Asn residues 554, 566, 618, and 633.We investigated the role of E-cadherin N-glycosylation in cell cycle progression by site-directed mutagenesis. We showed previously that all four potential N-glycosylation sites of E-cadherin were N-glycosylated in human breast carcinoma MDA-MB-435 cells. Removal of N-glycan at Asn633 dramatically affected E-cadherin stability. In this study we showed that E-cadherin mutant missing N-glycans at Asn554, Asn566 and Asn618 failed to induce cell cycle arrest in G1 phase and to suppress cell proliferation in comparison with wild-type E-cadherin. Moreover, N-glycans at Asn554 and Asn566, but not at Asn618, seemed to be indispensable for E-cadherin-mediated suppression of cell cycle progression.Removal of N-glycans at either Asn554 or Asn566 of E-cadherin was accompanied with the activation of the extracellular signal-regulated protein kinase signaling pathway. After treatment with PD98059, an inhibitor of the extraceilular signal-regulated protein kinase signaling pathway, wild-type E-cadherin transfected MDA-MB-435 and E-cadherin N-glycosylation-deficient mutant transfected MDA-MB-435 cells had equivalent numbers of cells in G1 phase. These findings implied that N-glycosylation might be crucial for E-cadherin-mediated suppression of cell cycle progression.

  13. Recycling of E-cadherin: a potential mechanism for regulating cadherin dynamics.

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    Le, T L; Yap, A S; Stow, J L

    1999-07-12

    E-Cadherin plays critical roles in many aspects of cell adhesion, epithelial development, and the establishment and maintenance of epithelial polarity. The fate of E-cadherin once it is delivered to the basolateral cell surface, and the mechanisms which govern its participation in adherens junctions, are not well understood. Using surface biotinylation and recycling assays, we observed that some of the cell surface E-cadherin is actively internalized and is then recycled back to the plasma membrane. The pool of E-cadherin undergoing endocytosis and recycling was markedly increased in cells without stable cell-cell contacts, i.e., in preconfluent cells and after cell contacts were disrupted by depletion of extracellular Ca2+, suggesting that endocytic trafficking of E-cadherin is regulated by cell-cell contact. The reformation of cell junctions after replacement of Ca2+ was then found to be inhibited when recycling of endocytosed E-cadherin was disrupted by bafilomycin treatment. The endocytosis and recycling of E-cadherin and of the transferrin receptor were similarly inhibited by potassium depletion and by bafilomycin treatment, and both proteins were accumulated in intracellular compartments by an 18 degrees C temperature block, suggesting that endocytosis may occur via a clathrin-mediated pathway. We conclude that a pool of surface E-cadherin is constantly trafficked through an endocytic, recycling pathway and that this may provide a mechanism for regulating the availability of E-cadherin for junction formation in development, tissue remodeling, and tumorigenesis.

  14. Mast cells infiltration and decreased E-cadherin expression in ketamine-induced cystitis

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    Mengqiang Li

    2015-01-01

    Conclusions: Increased mast cells in bladder wall and downregulated expression of E-cadherin junction protein in epithelial cells were probably associated with interstitial inflammation and fissures in mucosa. It implied that ketamine induced an interstitial cystitis.

  15. Prognostic implications of epithelial to mesenchymal transition related proteins (E-cadherin, Snail) and hypoxia inducible factor 1α in endometrioid endometrial carcinoma.

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    Abouhashem, Nehal S; Ibrahim, Doaa Abdelaziz; Mohamed, Abdel Motaleb

    2016-06-01

    The epithelial-mesenchymal transition (EMT) is an important step in the invasion and metastasis of cancer. E-cadherin downregulation, which is essentially controlled by EMT-mediated proteins such as Snail, is a main molecular feature of this process. Tumor hypoxia is one of the essential biological phenomena that are associated with the development and progression of various solid tumors. Recently, hypoxia and hypoxia-inducible factor 1α (HIF-1α) signaling pathway were identified to have an essential role in the regulation of EMT phenotype. The aim of the study was to evaluate the prognostic impact of EMT-related proteins (E-cadherin, Snail) and HIF-1α in endometrioid endometrial carcinoma (EEC) among Egyptian women. Immunohistochemical evaluation of E-cadherin, Snail, and HIF-1α expression was performed using 50 cases of EEC. The relationship between protein expression and clinicopathological features was investigated. The frequency of immunopositivity for E-cadherin, Snail, and HIF-1α in our cases of EEC was 82%, 28%, and 66%, respectively. Reduced E-cadherin and increased nuclear expression of Snail as well as HIF-1α were significantly associated with histopathologic grade, clinical stage myometrial invasion, and lymph node involvement. Statistical analysis showed a positive correlation between HIF-1α overexpression and Snail upregulation (τ= +0.252, P= .025); however, E-cadherin expression level was inversely correlated with enhanced Snail expression (τ= -0.450, PSnail immunoreactivity and positively related to E-cadherin expression. E-cadherin and Snail have a predictive value in EEC. In conclusion, the current study reveals that both Snail and HIF-1α expressions are significantly associated with poor prognosis in EEC; however, E-cadherin expression is considered a marker of good prognosis. E-cadherin and Snail expression has a predictive value in EEC management. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. A vertebrate-specific Chp-PAK-PIX pathway maintains E-cadherin at adherens junctions during zebrafish epiboly.

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    Tay, Hwee Goon; Ng, Yuen Wai; Manser, Ed

    2010-04-12

    In early vertebrate development, embryonic tissues modulate cell adhesiveness and acto-myosin contractility to correctly orchestrate the complex processes of gastrulation. E-cadherin (E-cadh) is the earliest expressed cadherin and is needed in the mesendodermal progenitors for efficient migration. Regulatory mechanisms involving directed E-cadh trafficking have been invoked downstream of Wnt11/5 signaling. This non-canonical Wnt pathway regulates RhoA-ROK/DAAM1 to control the acto-myosin network. However, in this context nothing is known of the intracellular signals that participate in the correct localization of E-cadh, other than a need for Rab5c signaling. By studying loss of Chp induced by morpholino-oligonucleotide injection in zebrafish, we find that the vertebrate atypical Rho-GTPase Chp is essential for the proper disposition of cells in the early embryo. The underlying defect is not leading edge F-actin assembly (prominent in the cells of the envelope layer), but rather the failure to localize E-cadh and beta-catenin at the adherens junctions. Loss of Chp results in delayed epiboly that can be rescued by mRNA co-injection, and phenocopies zebrafish E-cadh mutants. This new signaling pathway involves activation of an effector kinase PAK, and involvement of the adaptor PAK-interacting exchange factor PIX. Loss of signaling by any of the three components results in similar underlying defects, which is most prominent in the epithelial-like envelope layer. Our current study uncovers a developmental pathway involving Chp/PAK/PIX signaling, which helps co-ordinate E-cadh disposition to promote proper cell adhesiveness, and coordinate movements of the three major cell layers in epiboly. Our data shows that without Chp signaling, E-cadh shifts to intracellular vesicles rather than the adhesive contacts needed for directed cell movement. These events may mirror the requirement for PAK2 signaling essential for the proper formation of the blood-brain barrier.

  17. Tumor suppressor gene E-cadherin and its role in normal and malignant cells

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    Pećina-Šlaus Nives

    2003-10-01

    Full Text Available Abstract E-cadherin tumor suppressor genes are particularly active area of research in development and tumorigenesis. The calcium-dependent interactions among E-cadherin molecules are critical for the formation and maintenance of adherent junctions in areas of epithelial cell-cell contact. Loss of E-cadherin-mediated-adhesion characterises the transition from benign lesions to invasive, metastatic cancer. Nevertheless, there is evidence that E-cadherins may also play a role in the wnt signal transduction pathway, together with other key molecules involved in it, such as beta-catenins and adenomatous poliposis coli gene products. The structure and function of E-cadherin, gene and protein, in normal as well as in tumor cells are reviewed in this paper.

  18. CDH1 promoter hypermethylation and E-cadherin protein expression in infiltrating breast cancer

    DEFF Research Database (Denmark)

    Caldeira, José Roberto F; Prando, Erika C; Quevedo, Francisco C

    2006-01-01

    prognosis, and metastasis. Differential CpG island methylation in the promoter region of the CDH1 gene might be an alternative way for the loss of expression and function of E-cadherin, leading to loss of tissue integrity, an essential step in tumor progression. METHODS: The aim of our study was to assess...... was observed between CDH1 methylation and ER expression (p = 0.0301, Fisher's exact test). However, this finding was not considered significant after Bonferroni correction of p-value. CONCLUSION: Our preliminary findings suggested that abnormal CDH1 methylation occurs in high frequencies in infiltrating breast...

  19. The Epstein-Barr virus oncogene product, latent membrane protein 1, induces the downregulation of E-cadherin gene expression via activation of DNA methyltransferases

    Institute of Scientific and Technical Information of China (English)

    Chi-NeuTsai

    2005-01-01

    The latent membrane protein (LMP1) of Epstein-Barr virus (EBV) is expressed in EBV-associated nasopharyngeal carcinoma, which isnotoriously metastatic. Although it Is established that LMP1 represses E-cadherin expression and enhances the invasive ability of carcinoma cells, the mechanism underlying this repression remains to be elucidated. In this study, we demonstrate that LMP1 induces the expression and activity of the DNA methyltransferases 1, 3a, and 3b, using real-time reverse transcription-PCR and enzyme activity assay. This results in hypermethylation of the E-cadherin promoter and down-regulation of E-cadherin gene expression, as revealed by methylation-specific PCR, real-time reverse transcription-PeR and Western blotting data. The DNA methyltransferase inhibitor, 5'-Aza-2'dC, restores E-cadherin promoter activity and protein expression in LMPl-expressing cells, which in turn blocks cell migration ability, as demonstrated by the Transwell cell migration assay. Our findings suggest that LMP1 down-regulates E-cadherin gene expression and induces cell migration activity by using cellular DNA methylation machinery.

  20. Clinicopathological significance of ZEB-1 and E-cadherin proteins in patients with oral cavity squamous cell carcinoma

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    Yao X

    2017-02-01

    Full Text Available Xiaofeng Yao,1,2 Shanshan Sun,1,2 Xuan Zhou,1,2 Qiang Zhang,1,2 Wenyu Guo,1,2 Lun Zhang1,2 1Department of Maxillofacial and Otorhinolaryngology Head and Neck Surgery, Tianjin Medical University Cancer Institute and Hospital, 2Key Laboratory of Cancer Prevention and Therapy, National Clinical Research Center of Cancer, Tianjin, People’s Republic of China Background: Zinc-finger E-box binding homeobox 1 (ZEB-1, a member of the ZFH family, plays a key role in epithelial–mesenchymal transition during tumor progression in various cancers. However, little information is available on ZEB-1 expression in oral cavity squamous cell carcinoma (OSCC.Methods: The expression levels of ZEB-1 and E-cadherin were assessed by immunohistochemistry in a cohort of 120 patients with OSCC treated by curative operation, and then the correlations between ZEB-1 and E-cadherin expression and clinical factors were evaluated, including patient prognosis. Quantitative real-time polymerase chain reaction (qRT-PCR assays were performed to assess mRNA levels of ZEB-1 and E-cadherin in 20 matched OSCC specimens.Results: Patients were followed up for a median period of 66 months (range 8-116 months, and 5-year overall survival was 68.3%. Positive ZEB-1 and E-cadherin immunostaining reactivity was detected in 64 (53.3% and 53 (44.2% patients, respectively. There was a negative correlation between ZEB-1 expression and E-cadherin expression. In addition, overexpression of ZEB-1 was significantly associated with recurrence, lymph node metastasis, and pathologic grading of patients, loss of E-cadherin was significantly associated with lymph node metastasis and pathologic grading of patients. Univariate analysis showed that increased ZEB-1 expression, loss of E-cadherin expression, lymph node metastasis, recurrence, and pathology grade were prognostic factors. In multivariate analysis, increased ZEB-1 expression and recurrence remained independent prognostic factors. In particular

  1. Identification of E-cadherin signature motifs functioning as cleavage sites for Helicobacter pylori HtrA

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    Schmidt, Thomas P.; Perna, Anna M.; Fugmann, Tim; Böhm, Manja; Jan Hiss; Haller, Sarah; Götz, Camilla; Tegtmeyer, Nicole; Hoy, Benjamin; Rau, Tilman T.; Neri, Dario; Backert, Steffen; Schneider, Gisbert; Wessler, Silja

    2016-03-01

    The cell adhesion protein and tumour suppressor E-cadherin exhibits important functions in the prevention of gastric cancer. As a class-I carcinogen, Helicobacter pylori (H. pylori) has developed a unique strategy to interfere with E-cadherin functions. In previous studies, we have demonstrated that H. pylori secretes the protease high temperature requirement A (HtrA) which cleaves off the E-cadherin ectodomain (NTF) on epithelial cells. This opens cell-to-cell junctions, allowing bacterial transmigration across the polarised epithelium. Here, we investigated the molecular mechanism of the HtrA-E-cadherin interaction and identified E-cadherin cleavage sites for HtrA. Mass-spectrometry-based proteomics and Edman degradation revealed three signature motifs containing the [VITA]-[VITA]-x-x-D-[DN] sequence pattern, which were preferentially cleaved by HtrA. Based on these sites, we developed a substrate-derived peptide inhibitor that selectively bound and inhibited HtrA, thereby blocking transmigration of H. pylori. The discovery of HtrA-targeted signature sites might further explain why we detected a stable 90 kDa NTF fragment during H. pylori infection, but also additional E-cadherin fragments ranging from 105 kDa to 48 kDa in in vitro cleavage experiments. In conclusion, HtrA targets E-cadherin signature sites that are accessible in in vitro reactions, but might be partially masked on epithelial cells through functional homophilic E-cadherin interactions.

  2. Reduced E-cadherin expression is associated with abdominal pain and symptom duration in a study of alternating and diarrhea predominant IBS.

    LENUS (Irish Health Repository)

    Wilcz-Villega, E

    2013-11-29

    Increased intestinal permeability and altered expression of tight junction (TJ) proteins may be implicated in the pathogenesis of irritable bowel syndrome (IBS). This study aimed to investigate the expression of adherens junction (AJ) protein E-cadherin and TJ proteins zonula occludens (ZO)-1 and claudin (CLD)-1 and associations with IBS symptoms.

  3. Aberrant E-cadherin staining patterns in invasive mammary carcinoma

    Directory of Open Access Journals (Sweden)

    Brogi Edi

    2005-11-01

    Full Text Available Abstract Background E-cadherin, a cell surface protein involved in cell adhesion, is present in normal breast epithelium, benign breast lesions, and in breast carcinoma. Alterations in the gene CDH1 on chromosome 16q22 are associated with changes in E-cadherin protein expression and function. Inactivation of E-cadherin in lobular carcinomas and certain diffuse gastric carcinomas may play a role in the dispersed, discohesive "single cell" growth patterns seen in these tumors. The molecular "signature" of mammary lobular carcinomas is the loss of E-cadherin protein expression as evidenced by immunohistochemistry, whereas ductal carcinomas are typically E-cadherin positive. Patients and methods We report on E-cadherin immunostaining patterns in five cases of invasive mammary carcinoma Results These were five exceptional instances in which the E-cadherin immunophenotype did not correspond to the apparent histologic classification of the lesion. These cases which are exceedingly rare in our experience are the subject of this report. Conclusion Findings such as those illustrated in this study occur in virtually all biologic phenomena and they do not invalidate the very high degree of correlation between the expression of E-cadherin and the classification of breast carcinomas as ductal or lobular type on the basis of conventional histologic criteria.

  4. Hepatitis C virus depends on E-cadherin as an entry factor and regulates its expression in epithelial-to-mesenchymal transition.

    Science.gov (United States)

    Li, Qisheng; Sodroski, Catherine; Lowey, Brianna; Schweitzer, Cameron J; Cha, Helen; Zhang, Fang; Liang, T Jake

    2016-07-01

    Hepatitis C virus (HCV) enters the host cell through interactions with a cascade of cellular factors. Although significant progress has been made in understanding HCV entry, the precise mechanisms by which HCV exploits the receptor complex and host machinery to enter the cell remain unclear. This intricate process of viral entry likely depends on additional yet-to-be-defined cellular molecules. Recently, by applying integrative functional genomics approaches, we identified and interrogated distinct sets of host dependencies in the complete HCV life cycle. Viral entry assays using HCV pseudoparticles (HCVpps) of various genotypes uncovered multiple previously unappreciated host factors, including E-cadherin, that mediate HCV entry. E-cadherin silencing significantly inhibited HCV infection in Huh7.5.1 cells, HepG2/miR122/CD81 cells, and primary human hepatocytes at a postbinding entry step. Knockdown of E-cadherin, however, had no effect on HCV RNA replication or internal ribosomal entry site (IRES)-mediated translation. In addition, an E-cadherin monoclonal antibody effectively blocked HCV entry and infection in hepatocytes. Mechanistic studies demonstrated that E-cadherin is closely associated with claudin-1 (CLDN1) and occludin (OCLN) on the cell membrane. Depletion of E-cadherin drastically diminished the cell-surface distribution of these two tight junction proteins in various hepatic cell lines, indicating that E-cadherin plays an important regulatory role in CLDN1/OCLN localization on the cell surface. Furthermore, loss of E-cadherin expression in hepatocytes is associated with HCV-induced epithelial-to-mesenchymal transition (EMT), providing an important link between HCV infection and liver cancer. Our data indicate that a dynamic interplay among E-cadherin, tight junctions, and EMT exists and mediates an important function in HCV entry.

  5. Aberrant distributions and relationships among E-cadherin, beta-catenin, and connexin 26 and 43 in endometrioid adenocarcinomas.

    Science.gov (United States)

    Wincewicz, Andrzej; Baltaziak, Marek; Kanczuga-Koda, Luiza; Lesniewicz, Tomasz; Rutkowski, Ryszard; Sobaniec-Lotowska, Maria; Sulkowski, Stanislaw; Koda, Mariusz; Sulkowska, Mariola

    2010-07-01

    During carcinogenesis, loss of intracellular cohesion is observed among cancer cells with altered expression of such adhesion molecules as E-cadherin and beta-catenin, and aberrant expression and cellular location of intercellular gap junction proteins-connexins. The aim of this study was to evaluate immunohistochemically the expression and relationship between E-cadherin and beta-catenin, and the connexins Cx26 and Cx43 in 86 endometrioid adenocarcinomas. The aberrant cytoplasmic translocation of the studied proteins was a predominant finding, whereas only a minority of cases showed normal, nuclear beta-catenin labeling or membranous distribution of the remaining molecules. E-cadherin was positively and significantly associated with beta-catenin (P=0.001, r=0.366), as was Cx26 with Cx43 (P<0.001, r=0.719), E-cadherin with Cx26 (P<0.001, r=0.413), and E-cadherin and Cx43 (P<0.001, r=0.434) in all cancers. A subgroup of endometrioid adenocarcinomas (FIGO IB+II) exclusively showed a positive significant association between the expression of beta-catenin and Cx26 (P=0.038, r=0.339). In addition, there were significantly more beta-catenin-positive carcinomas among superficially spreading cancers (FIGO IA) than among deeper invading neoplasms (FIGO IB+II) (P=0.056). The altered location of the studied proteins indicates impairment of their physiological functions. In particular, normal membranous distribution of E-cadherin and connexins is lost and replaced by abnormal cytoplasmic accumulation in most cancers, and thus intercellular ties are expected to be weakened and loosened as a consequence. In contrast, the lack of relationship between beta-catenin and connexins, E-cadherin seems to be closely associated with the expression of Cx26 and Cx43 in endometrioid adenocarcinomas.

  6. EXPRESSION OF E-CADHERIN/CATENIN COMPLEX IN BREAST CANCER

    Institute of Scientific and Technical Information of China (English)

    LIU Zhen; CUI Dong-xu; LIU Bao-lin; ZHANG Xiao-bo; MA Wen-feng; ZHANG Qiang

    2006-01-01

    Objective: To detect the expressions of E-cadherin, (-catenin and (-catenin and analyze the relationship between E- cadherin-catenin adhesion complex and clinicopathological features in breast cancer. Methods: The expressions of E-cadherin, (-cadherin and (-catenin in specimens of 54 breast cancer, 21 normal breast tissues around tumor, 15 breast hyperplasia of usual type and 15 breast atypical hyperplasia were detected by immunohistochemical method. Results: In 21 normal breast tissues, E-cadherin and (-catenin were expressed on cell membrane of ductal and acinic cells, showing cellular contour and border among cells. The staining character of the three proteins in breast hyperplasia of usual type was the same as that in normal breast tissue. In breast atypical hyperplasia, the abnormal expression rates of E-cadherin, (-catenin and (-catenin were 6.7%, 13.3% and 26.7%, respectively. The total abnormal expression rate of E-cadherin-catenin complex was 33.3%. In breast cancer, the abnormal expression rates of E-cadherin, (-catenin and (-catenin were 51.9%, 63.0% and 61.1%, respectively. The total abnormal expression rate of E-cadherin-catenin complex was 88.9%. Abnormal expression of E-cadherin and (-catenin were significantly correlated with histological grade. Abnormal expressions of (-catenin and (-catenin were significantly correlated with TNM staging, axillary lymph nodes metastasis and postoperative distant metastasis. Abnormal expression of E-cadherin-catenin complex was correlated with TNM staging, histological grade and axillary lymph nodes. Abnormal expression of (-catenin was negatively correlated with expression of HER-2. COX multiple factor analysis showed that E-cadherin or (-catenin or (-catenin was not independent prognostic indicator. Conclusion: Abnormal expressions of E-cadherin, (-catenin and (-catenin frequently occur in breast cancer. Abnormal expression of E-cadherin-catenin complex is correlated with differentiation disturbance and metastasis

  7. Interaction of E-cadherin and PTEN regulates morphogenesis and growth arrest in human mammary epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Fournier, Marcia V.; Fata, Jimmie E.; Martin, Katherine J.; Yaswen, Paul; Bissell, Mina J.

    2009-06-03

    PTEN is a dual function phosphatase with tumor suppressor function compromised in a wide spectrum of cancers. Because tissue polarity and architecture are crucial modulators of normal and malignant behavior, we postulated that PTEN may play a role in maintenance of tissue integrity. We used two non-malignant human mammary epithelial cell lines (HMECs) that form polarized, growth-arrested structures (acini) when cultured in 3-dimensional laminin-rich extracellular matrix gels (3D lrECM). As acini begin to form, PTEN accumulates in both the cytoplasm, and at cell-cell contacts where it colocalizes with E-cadherin/{beta}-catenin complex. Reduction of PTEN levels by shRNA in lrECM prevents formation of organized breast acini and disrupts growth arrest. Importantly, disruption of acinar polarity and cell-cell contact by E-cadherin function-blocking antibodies reduces endogenous PTEN protein levels and inhibits its accumulation at cell-cell contacts. Conversely, in SKBR3 breast cancer cells lacking endogenous E-cadherin expression, exogenous introduction of E-cadherin gene causes induction of PTEN expression and its accumulation at sites of cell interactions. These studies provide evidence that E-cadherin regulates both the PTEN protein levels and its recruitment to cell-cell junctions in 3D lrECM indicating a dynamic reciprocity between architectural integrity and the levels and localization of PTEN. This interaction thus appears to be a critical integrator of proliferative and morphogenetic signaling in breast epithelial cells.

  8. Glycogen Synthase Kinase 3 (GSK-3) influences epithelial barrier function by regulating Occludin, Claudin-1 and E-cadherin expression

    Energy Technology Data Exchange (ETDEWEB)

    Severson, Eric A.; Kwon, Mike; Hilgarth, Roland S.; Parkos, Charles A. [Epithelial Pathobiology Research Unit, Dept. of Pathology, Emory University, Atlanta, GA 30322 (United States); Nusrat, Asma, E-mail: anusrat@emory.edu [Epithelial Pathobiology Research Unit, Dept. of Pathology, Emory University, Atlanta, GA 30322 (United States)

    2010-07-02

    The Apical Junctional Complex (AJC) encompassing the tight junction (TJ) and adherens junction (AJ) plays a pivotal role in regulating epithelial barrier function and epithelial cell proliferative processes through signaling events that remain poorly characterized. A potential regulator of AJC protein expression is Glycogen Synthase Kinase-3 (GSK-3). GSK-3 is a constitutively active kinase that is repressed during epithelial-mesenchymal transition (EMT). In the present study, we report that GSK-3 activity regulates the structure and function of the AJC in polarized model intestinal (SK-CO15) and kidney (Madin-Darby Canine Kidney (MDCK)) epithelial cells. Reduction of GSK-3 activity, either by small molecule inhibitors or siRNA targeting GSK-3 alpha and beta mRNA, resulted in increased permeability to both ions and bulk solutes. Immunofluorescence labeling and immunoblot analyses revealed that the barrier defects correlated with decreased protein expression of AJC transmembrane proteins Occludin, Claudin-1 and E-cadherin without influencing other TJ proteins, Zonula Occludens-1 (ZO-1) and Junctional Adhesion Molecule A (JAM-A). The decrease in Occludin and E-cadherin protein expression correlated with downregulation of the corresponding mRNA levels for these respective proteins following GSK-3 inhibition. These observations implicate an important role of GSK-3 in the regulation of the structure and function of the AJC that is mediated by differential modulation of mRNA transcription of key AJC proteins, Occludin, Claudin-1 and E-cadherin.

  9. Reggies/flotillins regulate E-cadherin-mediated cell contact formation by affecting EGFR trafficking.

    Science.gov (United States)

    Solis, Gonzalo P; Schrock, Yvonne; Hülsbusch, Nikola; Wiechers, Marianne; Plattner, Helmut; Stuermer, Claudia A O

    2012-05-01

    The reggie/flotillin proteins are implicated in membrane trafficking and, together with the cellular prion protein (PrP), in the recruitment of E-cadherin to cell contact sites. Here, we demonstrate that reggies, as well as PrP down-regulation, in epithelial A431 cells cause overlapping processes and abnormal formation of adherens junctions (AJs). This defect in cell adhesion results from reggie effects on Src tyrosine kinases and epidermal growth factor receptor (EGFR): loss of reggies reduces Src activation and EGFR phosphorylation at residues targeted by Src and c-cbl and leads to increased surface exposure of EGFR by blocking its internalization. The prolonged EGFR signaling at the plasma membrane enhances cell motility and macropinocytosis, by which junction-associated E-cadherin is internalized and recycled back to AJs. Accordingly, blockage of EGFR signaling or macropinocytosis in reggie-deficient cells restores normal AJ formation. Thus, by promoting EGFR internalization, reggies restrict the EGFR signaling involved in E-cadherin macropinocytosis and recycling and regulate AJ formation and dynamics and thereby cell adhesion.

  10. Relation among p130Cas, E-cadherin andβ-catenin expression, clinicopathologic signiifcance and prognosis in human hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    Cheng Guo; Qing-Guang Liu; Wei Yang; Zheng-Liang Zhang; Ying-Min Yao

    2008-01-01

    BACKGROUND:p130Cas (p130Crk-associated substance) is a junction protein that is important to the adhesion between cytoskeleton and extracellular matrix. Also, the adhesion molecules E-cadherin and β-catenin play important roles in the invasiveness of carcinoma. This study was undertaken to investigate the effects of p130Cas, E-cadherin andβ-catenin on the invasion, metastasis and prognosis of hepatocellular carcinoma (HCC). METHODS:Immunohistochemistry was used to evaluate the expression of p130Cas, E-cadherin, and β-catenin in 40 patients with HCC. All patients were followed up postoperatively, and the relationship between expression and clinicopathological prognostic parameters was analyzed. RESULTS: The positive expression rates of p130Cas and E-cadherin in HCC tissue (n=40) were 62.50%and 55.00%, but in normal liver tissue 10%, and 100%, respectively (P CONCLUSIONS:In HCC, there is a negative correlation between the positive expression of p130Cas and the normal expression of the adhesion molecules E-cadherin/β-catenin, and p130Cas plays important roles in the invasion, metastasis and prognosis of HCC. p130Cas may be involved in alterating the structure and function of E-cadherin/β-catenin, by regulating tyrosine phosphorylation via the p130Cas-Src signal pathway.

  11. Desmoglein 3, via an interaction with E-cadherin, is associated with activation of Src.

    Directory of Open Access Journals (Sweden)

    Siu Man Tsang

    Full Text Available BACKGROUND: Desmoglein 3 (Dsg3, a desmosomal adhesion protein, is expressed in basal and immediate suprabasal layers of skin and across the entire stratified squamous epithelium of oral mucosa. However, increasing evidence suggests that the role of Dsg3 may involve more than just cell-cell adhesion. METHODOLOGY/PRINCIPAL FINDINGS: To determine possible additional roles of Dsg3 during epithelial cell adhesion we used overexpression of full-length human Dsg3 cDNA, and RNAi-mediated knockdown of this molecule in various epithelial cell types. Overexpression of Dsg3 resulted in a reduced level of E-cadherin but a colocalisation with the E-cadherin-catenin complex of the adherens junctions. Concomitantly these transfected cells exhibited marked migratory capacity and the formation of filopodial protrusions. These latter events are consistent with Src activation and, indeed, Src-specific inhibition reversed these phenotypes. Moreover Dsg3 knockdown, which also reversed the decreased level of E-cadherin, partially blocked Src phosphorylation. CONCLUSIONS/SIGNIFICANCE: Our data are consistent with the possibility that Dsg3, as an up-stream regulator of Src activity, helps regulate adherens junction formation.

  12. A-kinase anchoring proteins contribute to loss of E-cadherin and bronchial epithelial barrier by cigarette smoke

    NARCIS (Netherlands)

    Oldenburger, Anouk; Poppinga, Wilfred J; Kos, Fleur; de Bruin, Harold G; Rijks, Wolter F; Heijink, Hilde; Timens, Wim; Meurs, Hermanus; Maarsingh, Harm; Schmidt, Martina

    2014-01-01

    Airway epithelium, which forms the first barrier towards environmental insults, is disturbed by cigarette smoking, a major risk factor for developing chronic obstructive pulmonary disease (COPD). A-kinase anchoring proteins (AKAP) maintain endothelial barrier function and coordinate subcellular loca

  13. E-cadherin in gastric cancer

    Institute of Scientific and Technical Information of China (English)

    Annie On On Chan

    2006-01-01

    Cadherin is an adhesion molecule and a superfamily of calcium-mediated membrane glycoproteins. E-cadherin is the prototype of the class E-cadherin that links to catenins to form the cytoskeleton. Recent evidence has shown that E-cadherin not only acts as an adhesive, but also plays important roles in growth development and carcinogenesis. It has been recently viewed as an invasion as well as a growth suppressor gene. This review summarizes the recent discoveries on E-cadherin and its role in gastric cancer. In particular, our work on E-cadherin in gastric cancer, including its relation with Helicobacter pylori and clinical applications, are described in detail.

  14. Distinct interactions with cellular E-cadherin of the two virulent metalloproteinases encoded by a Bacteroides fragilis pathogenicity island.

    Science.gov (United States)

    Remacle, Albert G; Shiryaev, Sergey A; Strongin, Alex Y

    2014-01-01

    Bacteroides fragilis causes the majority of Gram-negative anaerobic infections in the humans. The presence of a short, 6-kb, pathogenicity island in the genome is linked to enterotoxigenic B. fragilis (ETBF). The role of the enterotoxin in B. fragilis virulence, however, remains to be determined, as the majority of clinical isolates lack ETBF genes and healthy individuals carry enterotoxin-positive B. fragilis. The island encodes secretory metalloproteinase II (MPII) and one of three homologous enterotoxigenic fragilysin isoenzymes (FRA; also termed B. fragilis toxin or BFT). The secretory metalloproteinases expressed from the genes on the B. fragilis pathogenicity island may have pathological importance within the gut, not linked to diarrhea. MPII and FRA are counter-transcribed in the bacterial genome, implying that regardless of their structural similarity and overlapping cleavage preferences these proteases perform distinct and highly specialized functions in the course of B. fragilis infection. The earlier data by us and others have demonstrated that FRA cleaves cellular E-cadherin, an important adherens junction protein, and weakens cell-to-cell contacts. Using E-cadherin-positive and E-cadherin-deficient cancer cells, and the immunostaining, direct cell binding and pull-down approaches, we, however, demonstrated that MPII via its catalytic domain efficiently binds, rather than cleaves, E-cadherin. According to our results, E-cadherin is an adherens junction cellular receptor, rather than a proteolytic target, of the B. fragilis secretory MPII enzyme. As a result of the combined FRA and MPII proteolysis, cell-to-cell contacts and adherens junctions are likely to weaken further.

  15. Distinct interactions with cellular E-cadherin of the two virulent metalloproteinases encoded by a Bacteroides fragilis pathogenicity island.

    Directory of Open Access Journals (Sweden)

    Albert G Remacle

    Full Text Available Bacteroides fragilis causes the majority of Gram-negative anaerobic infections in the humans. The presence of a short, 6-kb, pathogenicity island in the genome is linked to enterotoxigenic B. fragilis (ETBF. The role of the enterotoxin in B. fragilis virulence, however, remains to be determined, as the majority of clinical isolates lack ETBF genes and healthy individuals carry enterotoxin-positive B. fragilis. The island encodes secretory metalloproteinase II (MPII and one of three homologous enterotoxigenic fragilysin isoenzymes (FRA; also termed B. fragilis toxin or BFT. The secretory metalloproteinases expressed from the genes on the B. fragilis pathogenicity island may have pathological importance within the gut, not linked to diarrhea. MPII and FRA are counter-transcribed in the bacterial genome, implying that regardless of their structural similarity and overlapping cleavage preferences these proteases perform distinct and highly specialized functions in the course of B. fragilis infection. The earlier data by us and others have demonstrated that FRA cleaves cellular E-cadherin, an important adherens junction protein, and weakens cell-to-cell contacts. Using E-cadherin-positive and E-cadherin-deficient cancer cells, and the immunostaining, direct cell binding and pull-down approaches, we, however, demonstrated that MPII via its catalytic domain efficiently binds, rather than cleaves, E-cadherin. According to our results, E-cadherin is an adherens junction cellular receptor, rather than a proteolytic target, of the B. fragilis secretory MPII enzyme. As a result of the combined FRA and MPII proteolysis, cell-to-cell contacts and adherens junctions are likely to weaken further.

  16. Expression and clinical significance of E-cadherin,β-catenin and E-cadherin-catenins complex in breast cancer and precancerous lesions

    Institute of Scientific and Technical Information of China (English)

    Zuofeng Zhang; Shuguang Yang; Gangping Wang

    2014-01-01

    Objective: The aim of our study was to observe the expressions and clinical Significance of E-cadherin, β-catenin and E-cadherin-catenins complex in breast cancer and precancerous lesions, and analyze the relationship between the ex-pressions and clinicopathological features in breast cancer. Methods: Immunhistochemical UltraSensitiveTM S-P method was employed to detect the expression of E-cadherin, β-catenin and E-cadherin-catenins complex in 128 cases of invasive ductal carcinomas, 89 cases of ductal carcinoma in situ and 57 cases of atypical ductal hyperplasia, 53 cases of usual ductal hyper-plasia breast tissues were selected as a control group. The express of E-cadherin, β-catenin and their relationship with mult biological parameters including histological grade, region lymph node metastasis, distant metastasis and recurrence on files were also assessed. Results: (1) The staining patterns character of E-cadherin, β-catenin and E-cadherin-catenins complex:In UDH breast tissues, E-cadherin and a-catenin were expressed on cellmembrane of ductal and acinic cells, showing cellular contour and border among cells. The abnormal expression of the three proteins occurred in breast invasive ductal carcinomas, ductal carcinoma in situ and atypical ductal hyperplasia tissues, showing cytoplasmic or nuclear staining, decrease and loss of cytomembrane staining. (2) The abnormal expression rates of E-cadherin, β-catenin and E-cadherin-catenins complex in invasive ductal carcinomas were 53.91%, 65.63% and 81.25%, which were significantly higher than that in ductal carcinoma in situ, atypical ductal hyperplasia, usual ductal hyperplasia tissues (P 0.05). (3) There was a significantly dif erence in the mean E-cadherin, β-catenin and E-cadherin-catenins complex frequency between estrogen receptor & progesterone receptor positive IDC group and negative group, epidermal growth factor receptor type 2 (HER2/neu) positive and negative groups, Ki-67 proliferation index ≤ 14

  17. Dysregulation of E-cadherin in Chronic Rhinosinusitis with Nasal Polyps

    Institute of Scientific and Technical Information of China (English)

    孔维佳; 吴俊华; 王彦君; 乐建新; 张松; 俞艳萍

    2010-01-01

    E-cadherin is a key epithelial protein and adhesive molecule. This study detected the E-cadherin expression in patients with chronic rhinosinusitis with nasal polyps (CRSwNP) and controls, and analyzed its possible role in the pathogenesis of CRSwNP. The expression of E-cadherin was detected by using Western blotting and immunohistochemistry in controls and patients with CRSwNP. Computed tomography (CT) scan findings were scored. The results showed that the E-cadherin expression was up-regulated in patients...

  18. Metastasis-associated protein 2 (MTA2) promotes the metastasis of non-small-cell lung cancer through the inhibition of the cell adhesion molecule Ep-CAM and E-cadherin.

    Science.gov (United States)

    Zhang, Bin; Zhang, Hao; Shen, Gang

    2015-08-01

    Metastasis-associated protein 2 is considered as an intrinsic subunit of the nucleosome remodelling and histone deacetylase complex, which contributes to the epigenetic silencing genes. More and more evidence suggests that metastasis-associated protein 2 is required to maintain the malignant phenotype, but the role of metastasis-associated protein 2 function in mediating tumour metastasis in non-small-cell lung cancer has not been explored. Bioinformatics was used to detect the GEO 3141 database, the online tool of Kmplot was used to confirm the high expression of metastasis-associated protein 2 in influencing 5-year overall survival. Wound-healing assay, Transwell invasion assay and Living imaging assay together showed that MTA2 shRNA inhibited cell migration and invasion in vitro and in vivo. Chromatin immunoprecipitation, quantitative chromatin immunoprecipitation and luciferase reporter assays showed metastasis-associated protein 2 binding on the promoter of the epithelial transmembrane glycoprotein (Ep-CAM) and cell adhesion molecule E-cadherin. The patient samples collected in our hospital show that metastasis-associated protein 2 was expressed in aggressive lung cancer cells, and its higher expression is correlated with poor prognosis. Metastasis-associated protein 2 promoted cell migration and invasion in vitro and in vivo through binding on the promoter of Ep-CAM and E-cadherin. Luciferase reporter assays showed repressed or enhanced E-cadherin or Ep-CAM promoter-driven luciferase reporter under metastasis-associated protein 2 overexpression or depletion. The changes in the level of protein and RNA implied that suppression of downstream E-cadherin or Ep-CAM was an important mechanism by which metastasis-associated protein 2 triggered epithelial-mesenchymal transition and metastasis. Together, our experiments reveal the mechanism for metastasis-associated protein 2 in facilitating invasive potential of non-small-cell lung cancer cells, suggesting that

  19. Real-time study of E-cadherin and membrane dynamics in living animals: implications for disease modeling and drug development.

    Science.gov (United States)

    Serrels, Alan; Timpson, Paul; Canel, Marta; Schwarz, Juliane P; Carragher, Neil O; Frame, Margaret C; Brunton, Valerie G; Anderson, Kurt I

    2009-04-01

    The ability of tumor cells to invade and metastasize requires deregulation of interactions with adjacent cells and the extracellular matrix. A major challenge of cancer biology is to observe the dynamics of the proteins involved in this process in their functional and physiologic context. Here, for the first time, we have used photobleaching and photoactivation to compare the mobility of cell adhesion and plasma membrane probes in vitro and in tumors grown in mice (in vivo). We find differences between in vitro and in vivo recovery dynamics of two key molecules, the tumor suppressor E-cadherin and the membrane-targeting sequence of H-Ras. Our data show that E-cadherin dynamics are significantly faster in vivo compared with cultured cells, that the ratio of E-cadherin stabilized in cell-cell junctions is significantly higher in vivo, and that E-cadherin mobility correlates with cell migration. Moreover, quantitative imaging has allowed us to assess the effects of therapeutic intervention on E-cadherin dynamics using dasatinib, a clinically approved Src inhibitor, and show clear differences in the efficacy of drug treatment in vivo. Our results show for the first time the utility of photobleaching and photoactivation in the analysis of dynamic biomarkers in living animals. Furthermore, this work highlights critical differences in molecular dynamics in vitro and in vivo, which have important implications for the use of cultured disease models as surrogates for living tissue.

  20. EXPRESSION OF SURVIVIN AND E-CADHERIN IN BREAST CANCER

    Institute of Scientific and Technical Information of China (English)

    TIAN Xiao-feng; LIU Ji-hong; WANG Li-fen; FENG XIAO-Mei; YAO Ji-hong

    2005-01-01

    Objective: Survivin is a member of the inhibitor of apoptosis (IAP) family, and is involved in the regulation of cell division. E-cadherin functionally belongs to transmembrane glycoproteins family, it is responsible for intercellular junction mechanism that is crucial for the mutual association of vertebrate cells. These genes are thought to be associated with cancer aggression. This study was to investigate the relationship between surviving gene, E-cadherin expression and invasion clinicopathological features of breast cancer. Methods: The expression of surviving gene and E-cadherin were detected by SP immunohistochemical technique in tissues of 66 breast cancer, 20 breast fibroadenoma and 20 adjacent breast tissue. Results: The positive rate of surviving gene expression in breast cancer was 42.2%, significantly higher (P=0.025) than those in breast fibroadenoma (35.0%), and adjacent breast tissue (10.0%). The positive rate of E-cadherin in the groups of adjacent breast tissue, breast fibroadenoma and breast cancer were 100%, 100% and 42.4%, there was significant difference between the group of benign and malignant tumor (P=0.005). The positive rate of surviving in breast cancer with local lymph node metastasis was significant higher than that in breast cancer without lymph node metastasis (P=0.01), and E-cadherin in breast cancer with local lymph node metastasis was significant lower than that without lymph node metastasis (P=o.o1). There was no significant difference among the groups of pathological types and TNM stages in the expression of surviving (P=0.966 & P=0.856), but there was significant difference in the expression of E-cadherin among these groups (P=0.01 & P=0.023). Conclusion: The loss or decrease of E-cadherin expression may promote the exfoliation of cancerous cells from original tissues, and surviving gene may promote the viability of the exfoliated cancer cells and the formation of new metastasis focus. These 2 factors cooperate with each other

  1. E-Cadherin As A Chemotherapy Resistance Mechanism On Metastatic Breast Cancer

    Science.gov (United States)

    2011-05-01

    mediated junctions. Am J Physiol Gastrointest Liver Physiol 2009; 296 (2): G235-44. 17. Pece S, Chiariello M, Murga C, et al. Activation of the...the E-cadherin adhesion complex. J Biol Chem 1999; 274 (27): 19347-51. 18. Pece S, Gutkind JS. Signaling from E-cadherins to the MAPK pathway by the...breast cancer metastasis. J Mammary Gland Biol Neoplasia 12(2-3): 153-62. 36. Pece , S and JS Gutkind (2000) Signaling from E-cadherins to the MAPK

  2. Arf6 regulates EGF-induced internalization of E-cadherin in breast cancer cells.

    Science.gov (United States)

    Xu, Rui; Zhang, Yujie; Gu, Luo; Zheng, Jianchao; Cui, Jie; Dong, Jing; Du, Jun

    2015-01-01

    E-cadherin internalization facilitates dissolution of adherens junctions and promotes tumor cell epithelial-mesenchymal transition (EMT) and migration. Our previous results have shown that Arf6 exerts pro-migratory action in breast cancer cells after EGF stimulation. Despite the fact that EGF signaling stimulates EMT of breast cancer cells, the effect of Arf6 on internalization of E-cadherin of breast cancer cells under EGF treatment remains to be determined. Here, we showed that EGF dose-dependently stimulated E-cadherin internalization by MCF-7 cells with the maximal effect at 50 ng/ml. Meanwhile, EGF treatment markedly increased Arf6 activation. Arf6 was involved in complexes of E-cadherin, and more E-cadherin was pulled down with Arf6 when the activity of the latter was increased. Immunoblotting and immunofluorescence assays showed that transfection breast cancer cells with Arf6-T27N or Arf6 siRNA suppressed EGF-induced E-cadherin internalization. Taken together, our study demonstrated that Arf6 activation plays a potential role in EGF-induced E-cadherin internalization, providing new mechanism underlying the effect of Arf6 on promoting breast cancer cell metastasis.

  3. A key role for E-cadherin in intestinal homeostasis and Paneth cell maturation.

    Science.gov (United States)

    Schneider, Marlon R; Dahlhoff, Maik; Horst, David; Hirschi, Benjamin; Trülzsch, Konrad; Müller-Höcker, Josef; Vogelmann, Roger; Allgäuer, Michael; Gerhard, Markus; Steininger, Sylvia; Wolf, Eckhard; Kolligs, Frank T

    2010-12-14

    E-cadherin is a major component of adherens junctions. Impaired expression of E-cadherin in the small intestine and colon has been linked to a disturbed intestinal homeostasis and barrier function. Down-regulation of E-cadherin is associated with the pathogenesis of infections with enteropathogenic bacteria and Crohn's disease. To genetically clarify the function of E-cadherin in intestinal homeostasis and maintenance of the epithelial defense line, the Cdh1 gene was conditionally inactivated in the mouse intestinal epithelium. Inactivation of the Cdh1 gene in the small intestine and colon resulted in bloody diarrhea associated with enhanced apoptosis and cell shedding, causing life-threatening disease within 6 days. Loss of E-cadherin led cells migrate faster along the crypt-villus axis and perturbed cellular differentiation. Maturation and positioning of goblet cells and Paneth cells, the main cell lineage of the intestinal innate immune system, was severely disturbed. The expression of anti-bacterial cryptidins was reduced and mice showed a deficiency in clearing enteropathogenic bacteria from the intestinal lumen. These results highlight the central function of E-cadherin in the maintenance of two components of the intestinal epithelial defense: E-cadherin is required for the proper function of the intestinal epithelial lining by providing mechanical integrity and is a prerequisite for the proper maturation of Paneth and goblet cells.

  4. A key role for E-cadherin in intestinal homeostasis and Paneth cell maturation.

    Directory of Open Access Journals (Sweden)

    Marlon R Schneider

    Full Text Available BACKGROUND: E-cadherin is a major component of adherens junctions. Impaired expression of E-cadherin in the small intestine and colon has been linked to a disturbed intestinal homeostasis and barrier function. Down-regulation of E-cadherin is associated with the pathogenesis of infections with enteropathogenic bacteria and Crohn's disease. METHODS AND FINDINGS: To genetically clarify the function of E-cadherin in intestinal homeostasis and maintenance of the epithelial defense line, the Cdh1 gene was conditionally inactivated in the mouse intestinal epithelium. Inactivation of the Cdh1 gene in the small intestine and colon resulted in bloody diarrhea associated with enhanced apoptosis and cell shedding, causing life-threatening disease within 6 days. Loss of E-cadherin led cells migrate faster along the crypt-villus axis and perturbed cellular differentiation. Maturation and positioning of goblet cells and Paneth cells, the main cell lineage of the intestinal innate immune system, was severely disturbed. The expression of anti-bacterial cryptidins was reduced and mice showed a deficiency in clearing enteropathogenic bacteria from the intestinal lumen. CONCLUSION: These results highlight the central function of E-cadherin in the maintenance of two components of the intestinal epithelial defense: E-cadherin is required for the proper function of the intestinal epithelial lining by providing mechanical integrity and is a prerequisite for the proper maturation of Paneth and goblet cells.

  5. CDH1 (E-cadherin) in testicular germ cell neoplasia: suppressed translation of mRNA in pre-invasive carcinoma in situ but increased protein levels in advanced tumours

    DEFF Research Database (Denmark)

    Sonne, Si Brask; Hoei-Hansen, Christina E; Nielsen, John E;

    2006-01-01

    E-cadherin (CDH1) is a transmembrane glycoprotein involved in cellular adhesion. In our recent microarray studies of testicular germ cell tumours (TGCTs) and the common precursor carcinoma in situ (CIS), CDH1 mRNA was highly expressed in CIS and embryonal carcinoma. It has previously been reported...... that the CDH1 protein is not expressed in CIS. To resolve the discrepancy, we performed a detailed analysis of the expression of CDH1 mRNA and protein in a series of normal and neoplastic testes. High expression of CDH1 mRNA in CIS was confirmed by real-time PCR and in situ hybridisation. At the protein level......, however, CDH1 was only detected with one of three tested antibodies, but Western blotting analysis with this antibody showed additional bands, suggesting unspecific staining. The levels of a CDH1 protein fragment in serum samples from 58 patients with TGCTs were analysed by ELISA; we found significantly...

  6. Impact of Snail and E-cadherin expression in pancreatic neuroendocrine tumors.

    Science.gov (United States)

    Yonemori, Keiichi; Kurahara, Hiroshi; Maemura, Kosei; Mataki, Yuko; Sakoda, Masahiko; Iino, Satoshi; Ueno, Shinichi; Shinchi, Hiroyuki; Natsugoe, Shoji

    2017-08-01

    Pancreatic neuroendocrine tumors (PNETs) are a rare type of malignancy with a prognosis that is relatively good, compared with that of pancreatic adenocarcinoma. However, a number of patients with PNETs have distant metastasis and a less favorable prognosis. Epithelial-mesenchymal transition (EMT) is essential for tumor progression and metastasis. Snail and E-cadherin serve key roles in the process of EMT in numerous tumor types, including gastric and pancreatic adenocarcinoma. However, the role of EMT in PNETs remains unclear. The aim of the present study was to investigate the significance of Snail and E-cadherin expression in PNETs. Tissue samples were obtained from 40 resected PNETs. The expression of Snail and E-cadherin was evaluated in the primary tumors using immunohistochemical staining. The association between protein expression and patient clinicopathological features was then analyzed. High and low Snail expression levels were observed in 11 (27.5%) and 29 (72.5%) patients, respectively. Preserved and reduced E-cadherin expression was observed in 19 (47.5%) and 21 (52.5%) patients, respectively. Patients with low Snail expression and preserved E-cadherin expression had a significantly lower risk of vascular invasion, lymphatic invasion, lymph node metastasis and liver metastasis and a lower WHO classification, as compared with the group that included patients with high Snail and reduced E-cadherin, high Snail and preserved E-cadherin, and low Snail and reduced E-cadherin expression. In addition, the patients with low Snail expression levels and preserved E-cadherin expression had more a favorable prognosis compared with the other group. The present study indicates that EMT serves an important role in tumor progression in PNETs. Immunohistochemical evaluation of Snail and E-cadherin is useful for predicting the risk of vessel invasion and metastasis in PNETs.

  7. The role of E-cadherin down-regulation in oral cancer: CDH1 gene expression and epigenetic blockage.

    Science.gov (United States)

    Pannone, G; Santoro, A; Feola, A; Bufo, P; Papagerakis, P; Lo Muzio, L; Staibano, S; Ionna, F; Longo, F; Franco, R; Aquino, G; Contaldo, M; De Maria, S; Serpico, R; De Rosa, A; Rubini, C; Papagerakis, S; Giovane, A; Tombolini, V; Giordano, A; Caraglia, M; Di Domenico, M

    2014-01-01

    The prognosis of the oral squamous cell carcinoma (OSCC) patients remains very poor, mainly due to their high propensity to invade and metastasize. E-cadherin reduced expression occurs in the primary step of oral tumour progression and gene methylation is a mode by which the expression of this protein is regulated in cancers. In this perspective, we investigated E-cadherin gene (CDH1) promoter methylation status in OSCC and its correlation with Ecadherin protein expression, clinicopathological characteristics and patient outcome. Histologically proven OSCC and paired normal mucosa were analyzed for CDH1 promoter methylation status and E-cadherin protein expression by methylation-specific polymerase chain reaction and immunohistochemistry. Colocalization of E-cadherin with epidermal growth factor (EGF) receptor (EGFR) was evidenced by confocal microscopy and by immunoprecipitation analyses. This study indicated E-cadherin protein down-regulation in OSCC associated with protein delocalization from membrane to cytoplasm. Low E-cadherin expression correlated to aggressive, poorly differentiated, high grade carcinomas and low patient survival. Moreover, protein down-regulation appeared to be due to E-cadherin mRNA downregulation and CDH1 promoter hypermethylation. In an in vitro model of OSCC the treatment with EGF caused internalization and co-localization of E-cadherin with EGFR and the addition of demethylating agents increased E-cadherin expression. Low E-Cadherin expression is a negative prognostic factor of OSCC and is likely due to the hypermethylation of CDH1 promoter. The delocalization of E-cadherin from membrane to cytoplasm could be also due to the increased expression of EGFR in OSCC and the consequent increase of E-cadherin co-internalization with EGFR.

  8. Influence of E-cadherin-mediated cell adhesion on mouse embryonic stem cells derivation from isolated blastomeres.

    Science.gov (United States)

    González, Sheyla; Ibáñez, Elena; Santaló, Josep

    2011-09-01

    Efforts to efficiently derive embryonic stem cells (ESC) from isolated blastomeres have been done to minimize ethical concerns about human embryo destruction. Previous studies in our laboratory indicated a poor derivation efficiency of mouse ESC lines from isolated blastomeres at the 8-cell stage (1/8 blastomeres) due, in part, to a low division rate of the single blastomeres in comparison to their counterparts with a higher number of blastomeres (2/8, 3/8 and 4/8 blastomeres). Communication and adhesion between blastomeres from which the derivation process begins could be important aspects to efficiently derive ESC lines. In the present study, an approach consisting in the adhesion of a chimeric E-cadherin (E-cad-Fc) to the blastomere surface was devised to recreate the signaling produced by native E-cadherin between neighboring blastomeres inside the embryo. By this approach, the division rate of 1/8 blastomeres increased from 44.6% to 88.8% and a short exposure of 24 h to the E-cad-Fc produced an ESC derivation efficiency of 33.6%, significantly higher than the 2.2% obtained from the control group without E-cad-Fc. By contrast, a longer exposure to the same chimeric protein resulted in higher proportions of trophoblastic vesicles. Thus, we establish an important role of E-cadherin-mediated adherens junctions in promoting both the division of single 1/8 blastomeres and the efficiency of the ESC derivation process.

  9. Differential Downregulation of E-Cadherin and Desmoglein by Epidermal Growth Factor

    Directory of Open Access Journals (Sweden)

    Miquella G. Chavez

    2012-01-01

    Full Text Available Modulation of cell : cell junctions is a key event in cutaneous wound repair. In this study we report that activation of the epidermal growth factor (EGF receptor disrupts cel : cell adhesion, but with different kinetics and fates for the desmosomal cadherin desmoglein and for E-cadherin. Downregulation of desmoglein preceded that of E-cadherin in vivo and in an EGF-stimulated in vitro wound reepithelialization model. Dual immunofluorescence staining revealed that neither E-cadherin nor desmoglein-2 internalized with the EGF receptor, or with one another. In response to EGF, desmoglein-2 entered a recycling compartment based on predominant colocalization with the recycling marker Rab11. In contrast, E-cadherin downregulation was accompanied by cleavage of the extracellular domain. A broad-spectrum matrix metalloproteinase inhibitor protected E-cadherin but not the desmosomal cadherin, desmoglein-2, from EGF-stimulated disruption. These findings demonstrate that although activation of the EGF receptor regulates adherens junction and desmosomal components, this stimulus downregulates associated cadherins through different mechanisms.

  10. Expression of E-Cadherin in Oral Squamous Cell Carcinoma is Associated with Clinical Prognosis

    Institute of Scientific and Technical Information of China (English)

    Jianming Zhang; Wei Zhang; Ping Gao; Yanqiu Li; Changyi Li; Sakan Maeda

    2006-01-01

    OBJECTIVE To investigate the correlation of E-cadherin expression with clinicopathological parameters and prognosis of patients with oral squamous cell carcinoma.METHODS We examined the expression of the protein E-cadherin in 43 oral squamous cell carcinoma (SCC) surgical speciments by SABC immunohistochemistry.RESULTS There was a significant correlation between the level of Ecadherin expression and tumor stage (P=0.024), invasive pattern (P=0.009) and lymph node metastasis (P=0.023). No relation was found with age (P=0.084), sex (P=1.356) and differentiation (P=0.877). Using the Kaplan-Meier method we demonstrated that those cases which showed E-cadherin expression (-) or (+) had a significantly poorer prognosis compared those cases which showed expression (++) or (+++) (P= 0.0146).CONCLUSION E-cadherin, is an important indicator of clinical diagnoses and prognositic marker for oral SCC patients.

  11. HAb18G/CD147 cell-cell contacts confer resistance of a HEK293 subpopulation to anoikis in an E-cadherin-dependent manner

    Directory of Open Access Journals (Sweden)

    Zhu Ping

    2010-04-01

    Full Text Available Abstract Background Acquisition of resistance to "anoikis" facilitates the survival of cells under independent matrix-deficient conditions, such as cells in tumor progression and the production of suspension culture cells for biomedical engineering. There is evidence suggesting that CD147, an adhesion molecule associated with survival of cells in tumor metastasis and cell-cell contacts, plays an important role in resistance to anoikis. However, information regarding the functions of CD147 in mediating cell-cell contacts and anoikis-resistance remains limited and even self-contradictory. Results An anoikis-resistant clone (HEK293ar, derived from anoikis-sensitive parental Human Embryonic Kidney 293 cells, survived anoikis by the formation of cell-cell contacts. The expression of HAb18G/CD147 (a member of the CD147 family was upregulated and the protein was located at cell-cell junctions. Upregulation of HAb18G/CD147 in suspended HEK293ar cells suppressed anoikis by mediating the formation of cell-cell adhesions. Anoikis resistance in HEK293ar cells also required E-cadherin-mediated cell-cell contacts. Knock-down of HAb18G/CD147 and E-cadherin inhibited cell-cell contacts formation and increased anoikis sensitivity respectively. When HAb18G/CD147 was downregulated, E-cadherin expression in HEK293ar cells was significantly suppressed; however, knockdown of E-cadherin by E-cadherin siRNA or blocking of E-cadherin binding activity with a specific antibody and EDTA had no significant effect on HAb18G/CD147 expression. Finally, pretreatment with LY294002, a phosphoinositide 3-kinase (PI3K/AKT inhibitor, disrupted cell-cell contacts and decreased cell number, but this was not the case in cells treated with the extracellular signal-regulated kinase (ERK inhibitor PD98059. Conclusions Our results provide new evidence that HAb18G/CD147-mediated cell-cell contact confers anoikis resistance in an E-cadherin-dependent manner; and cell-cell contact mediated

  12. Disordered beta-catenin expression and E-cadherin/CDH1 promoter methylation in gastric carcinoma

    Institute of Scientific and Technical Information of China (English)

    Li Wang; Fan Zhang; Ping-Ping Wu; Xu-Cheng Jiang; Lin Zheng; Ying-Yan Yu

    2006-01-01

    AIM: To investigate the distribution of beta-catenin in nuclei or membrane/cytoplasm of gastric carcinoma cells,the relationship between E-cadherin gene methylation and its expression, and the role of beta-catenin and E-cadherin as potential molecular markers in predicting tumor infiltration.METHODS: Twenty-nine cases of gastric carcinoma,classified as diffuse and intestinal variants, were selected for study. Nuclear and cytoplasmic proteins were purified and beta-catenin content was detected by ELISA. DNA methylation of E-cadherin/CDH1 gene promoter was studied by methylation-specific PCR and compaired with E-cadherin expression detected by immunohistochemistry.RESULTS: In 27 cases of gastric carcinoma, the ratio of beta-catenin content between nuclei and membrane/cytoplasm was correlated with the T-classification (r =0.392, P = 0.043). The significance was present between T2 and T3 groups. No correlation was detected between diffuse and intestinal variants in terms of their betacatenin distribution. In 21 cases of diffuse variants of gastric carcinoma, there was a difference in E-cadherin expression between CDH1 gene-methylated group and non-methylated group (29 % vs 71%, P = 0.027).No correlation between CDH1 gene methylation and T-classification was found, neither was the significance between E-cadherin expression and tumor infiltration grade.CONCLJSION: Comparative analysis of nuclear and membrane/cytoplasmic beta-catenin can predict local tumor infiltration. E-cadherin/CDH1 gene methylation is an important cause for its gene silence in diffuse variant gastric carcinoma. Methylation of CDH1 gene in the absence of E-cadherin is an early event in gastric carcinogenesis.

  13. Relationship between expression of E-cadherin-catenin complex and clinicopathologic characteristics of pancreatic cancer

    Institute of Scientific and Technical Information of China (English)

    Yu-Jun Li; Xiang-Rui Ji

    2003-01-01

    AIM: To investigate the expression of E-cadherin and alpha-catenin and beta-catenin in pancreatic carcinoma and itsrelationship with the clinicopathologic characteristics, andclarify the mechanism of invasion and metastasis ofpancreatic cancer.METHODS: The expression of E-cadherin and alpha-, beta-catenin was examined in 47 cases of infiltrative ductaladenocarcinoma of pancreas and 12 adult normal pancreatictissues by immunohistochemical technique.RESULTS: The immunoreactivity of E-cadherin and alpha-,beta-catenin was expressed by normal ductal and acinarcells with strong membranous staining at the intercellularborder in 12 cases of adult normal pancreatic tissues. Abnormalexpression of E-cadherin and alpha-, beta-catenin in 47pancreatic carcinoma tissues was demonstrated in 53.2 %,61.7 % and 68.1%, respectively. Both abnormal expressionof E-cadherin and alpha-catenin significantly correlated withdifferentiation, lymph node and liver metastases (P<0.05,respectively), whereas aberrant beta-catenin expression onlycorrelated with lymph node and liver metastases (P<0.001).Abnormal E-cadherin and alpha-, beta-catenin expressionwas not associated with tumor size, invasion and survivaltime of patients (P>0.05, all).CONCLUSION: Pancreatic cancer likely occurs in case ofE-cadherin-catenin complex genes mutations or deletionsand abnormal expression of proteins, which significantlycorrelate with the biologic character of the tumor and lymphnode and liver metastases. It is suggested that the abnormalE-cadherin-catenin complex expression plays an importantrole in the development and progression of tumor, and thusmay become a new marker in pancreatic cancer metastasis.

  14. E-cadherin couples death receptors to the cytoskeleton to regulate apoptosis.

    Science.gov (United States)

    Lu, Min; Marsters, Scot; Ye, Xiaofen; Luis, Elizabeth; Gonzalez, Lino; Ashkenazi, Avi

    2014-06-19

    Epithelial-to-mesenchymal transition (EMT) is a cellular process essential to the development and maintenance of solid tissues. In cancer, EMT suppresses apoptosis, but the mechanisms remain unclear. EMT selectively attenuated apoptosis signaling via the death receptors DR4 and DR5. Loss of the epithelial cell adhesion protein E-cadherin recapitulated this outcome, whereas homotypic E-cadherin engagement promoted apoptotic signaling via DR4/DR5, but not Fas. Depletion of α-catenin, which couples E-cadherin to the actin cytoskeleton, or actin polymerization inhibitors similarly attenuated DR4/DR5-induced apoptosis. E-cadherin bound specifically to ligated DR4/DR5, requiring extracellular cadherin domain 1 and calcium. E-cadherin augmented DR4/DR5 clustering and assembly of the death-inducing signaling complex (DISC), increasing caspase-8 activation in high molecular weight cell fractions. Conversely, EMT attenuated DR4/DR5-mediated DISC formation and caspase-8 stimulation. Consistent with these findings, epithelial cancer cell lines expressing higher E-cadherin levels displayed greater sensitivity to DR4/DR5-mediated apoptosis. These results have potential implications for tissue homeostasis as well as cancer therapy.

  15. E-cadherin mediates adhesion and endocytosis of Aspergillus fumigatus blastospores in human epithelial cells

    Institute of Scientific and Technical Information of China (English)

    XU Xiao-yong; SHI Yi; ZHANG Peng-peng; ZHANG Feng; SHEN Yu-ying; SU Xin; ZHAO Bei-lei

    2012-01-01

    Background Aspergillus fumigatus (A.fumigatus) is a ubiquitous saprophytic fungus responsible for the majority of invasive mold infections in patients undergoing chemotherapy,organ transplantation or with persistent neutropenia.This study aimed to determine the role of E-cadherin for adhesion and endocytosis of A.fumigatus blastospores in the human epithelial cell line A549.Methods A.fumigatus blastospores were incubated with the total protein of A549 to investigate the binding of E-cadherin and blastospores followed by an affinity purification procedure.After establishing the adhesion model,the adhesion and endocytosis of A.fumigatus blastospores by A549 cells were evaluated by down-regulating E-cadherin of A549 cells using blocking antibody or small interfering RNA (siRNA).Results E-cadherin was adhered to the surface of A.fumigatus blastospore.Adhesion and endocytosis of the blastospores were reduced by blocking or down-regulating E-cadherin in A549 cells.Conclusions E-cadherin is a receptor for adhesion and endocytosis of A.fumigatus blastospores in epithelial cells.This may open a new approach to treat this fungal infection.

  16. PRL-3 and E-cadherin show mutual interactions and participate in lymph node metastasis formation in gastric cancer.

    Science.gov (United States)

    Pryczynicz, Anna; Guzińska-Ustymowicz, Katarzyna; Niewiarowska, Katarzyna; Cepowicz, Dariusz; Kemona, Andrzej

    2014-07-01

    E-cadherin, a transmembrane adhesion molecule, and phosphatase of regenerating liver 3 (PRL-3) protein, a member of the family of tyrosine phosphatases, seem to be responsible for cancer cell migration. Therefore, the study objective was to determine a correlation between PRL-3 and E-cadherin, to assess their expression in neoplastic tissue and normal mucosa of the stomach, to analyze their effect on cancer advancement, and to evaluate their potential as prognostic markers in gastric cancer. The expressions of PRL-3 and E-cadherin were assessed immunohistochemically in 71 patients with gastric cancer. Positive expression of PRL-3 was observed in 42.2 % of gastric cancer cases, whereas E-cadherin expression was abnormal in 38 % of cases. The study revealed that the positive PRL-3 expression and abnormal E-cadherin expression were associated with mucinous gastric carcinoma and lymph node involvement. The former was also related to the infiltrating type of tumor and abnormal E-cadherin expression. The expression of PRL-3, but not of E-cadherin, was associated with shorter survival of patients. PRL-3 and E-cadherin exhibit interactions in gastric cancer and are involved in the formation of lymph node metastases. The PRL-3 protein can be an independent predictive factor of overall survival in gastric cancer patients.

  17. Preventing E-cadherin aberrant N-glycosylation at Asn-554 improves its critical function in gastric cancer.

    Science.gov (United States)

    Carvalho, S; Catarino, T A; Dias, A M; Kato, M; Almeida, A; Hessling, B; Figueiredo, J; Gärtner, F; Sanches, J M; Ruppert, T; Miyoshi, E; Pierce, M; Carneiro, F; Kolarich, D; Seruca, R; Yamaguchi, Y; Taniguchi, N; Reis, C A; Pinho, S S

    2016-03-31

    E-cadherin is a central molecule in the process of gastric carcinogenesis and its posttranslational modifications by N-glycosylation have been described to induce a deleterious effect on cell adhesion associated with tumor cell invasion. However, the role that site-specific glycosylation of E-cadherin has in its defective function in gastric cancer cells needs to be determined. Using transgenic mice models and human clinical samples, we demonstrated that N-acetylglucosaminyltransferase V (GnT-V)-mediated glycosylation causes an abnormal pattern of E-cadherin expression in the gastric mucosa. In vitro models further indicated that, among the four potential N-glycosylation sites of E-cadherin, Asn-554 is the key site that is selectively modified with β1,6 GlcNAc-branched N-glycans catalyzed by GnT-V. This aberrant glycan modification on this specific asparagine site of E-cadherin was demonstrated to affect its critical functions in gastric cancer cells by affecting E-cadherin cellular localization, cis-dimer formation, molecular assembly and stability of the adherens junctions and cell-cell aggregation, which was further observed in human gastric carcinomas. Interestingly, manipulating this site-specific glycosylation, by preventing Asn-554 from receiving the deleterious branched structures, either by a mutation or by silencing GnT-V, resulted in a protective effect on E-cadherin, precluding its functional dysregulation and contributing to tumor suppression.

  18. PKCζ Promotes Breast Cancer Invasion by Regulating Expression of E-cadherin and Zonula Occludens-1 (ZO-1) via NFκB-p65

    Science.gov (United States)

    Paul, Arindam; Danley, Marsha; Saha, Biswarup; Tawfik, Ossama; Paul, Soumen

    2015-01-01

    Atypical Protein Kinase C zeta (PKCζ) forms Partitioning-defective (PAR) polarity complex for apico-basal distribution of membrane proteins essential to maintain normal cellular junctional complexes and tissue homeostasis. Consistently, tumor suppressive role of PKCζ has been established for multiple human cancers. However, recent studies also indicate pro-oncogenic function of PKCζ without firm understanding of detailed molecular mechanism. Here we report a possible mechanism of oncogenic PKCζ signaling in the context of breast cancer. We observed that depletion of PKCζ promotes epithelial morphology in mesenchymal-like MDA-MB-231 cells. The induction of epithelial morphology is associated with significant upregulation of adherens junction (AJ) protein E-cadherin and tight junction (TJ) protein Zonula Occludens-1 (ZO-1). Functionally, depletion of PKCζ significantly inhibits invasion and metastatic progression. Consistently, we observed higher expression and activation of PKCζ signaling in invasive and metastatic breast cancers compared to non-invasive diseases. Mechanistically, an oncogenic PKCζ– NFκB-p65 signaling node might be involved to suppress E-cadherin and ZO-1 expression and ectopic expression of a constitutively active form of NFκB-p65 (S536E-NFκB-p65) significantly rescues invasive potential of PKCζ-depleted breast cancer cells. Thus, our study discovered a PKCζ - NFκB-p65 signaling pathway might be involved to alter cellular junctional dynamics for breast cancer invasive progression. PMID:26218882

  19. Carcinoembryonic antigen promotes colorectal cancer progression by targeting adherens junction complexes

    Energy Technology Data Exchange (ETDEWEB)

    Bajenova, Olga, E-mail: o.bazhenova@spbu.ru [Theodosius Dobzhansky Center for Genome Bioinformatics, St. Petersburg State University, St. Petersburg 199034 (Russian Federation); Department of Genetics and Biotechnology, St. Petersburg State University, St. Petersburg 199034 (Russian Federation); Department of Surgery and Biomedical Sciences, Creighton University, Omaha, NE 68178 (United States); Chaika, Nina [Department of Surgery and Biomedical Sciences, Creighton University, Omaha, NE 68178 (United States); Tolkunova, Elena; Davydov-Sinitsyn, Alexander [Institute of Cytology, Russian Academy of Sciences, St. Petersburg 194064 (Russian Federation); Gapon, Svetlana [Boston Children' s Hospital, Boston, MA 02115 (United States); Thomas, Peter [Department of Surgery and Biomedical Sciences, Creighton University, Omaha, NE 68178 (United States); O’Brien, Stephen [Theodosius Dobzhansky Center for Genome Bioinformatics, St. Petersburg State University, St. Petersburg 199034 (Russian Federation)

    2014-06-10

    Oncomarkers play important roles in the detection and management of human malignancies. Carcinoembryonic antigen (CEA, CEACAM5) and epithelial cadherin (E-cadherin) are considered as independent tumor markers in monitoring metastatic colorectal cancer. They are both expressed by cancer cells and can be detected in the blood serum. We investigated the effect of CEA production by MIP101 colorectal carcinoma cell lines on E-cadherin adherens junction (AJ) protein complexes. No direct interaction between E-cadherin and CEA was detected; however, the functional relationships between E-cadherin and its AJ partners: α-, β- and p120 catenins were impaired. We discovered a novel interaction between CEA and beta-catenin protein in the CEA producing cells. It is shown in the current study that CEA overexpression alters the splicing of p120 catenin and triggers the release of soluble E-cadherin. The influence of CEA production by colorectal cancer cells on the function of E-cadherin junction complexes may explain the link between the elevated levels of CEA and the increase in soluble E-cadherin during the progression of colorectal cancer. - Highlights: • Elevated level of CEA increases the release of soluble E-cadherin during the progression of colorectal cancer. • CEA over-expression alters the binding preferences between E-cadherin and its partners: α-, β- and p120 catenins in adherens junction complexes. • CEA produced by colorectal cancer cells interacts with beta-catenin protein. • CEA over-expression triggers the increase in nuclear beta-catenin. • CEA over-expression alters the splicing of p120 catenin protein.

  20. Analysis of metastasis suppressing function of E-cadherin in gastric cancer cells by RNAi

    Institute of Scientific and Technical Information of China (English)

    Zhi-Hong Zheng; Xiu-Ju Sun; Hai-Tao Zhou; Chao Shang; Hong Ji; Kai-Lai Sun

    2005-01-01

    AIM: To study the effect of inhibited E-cadherin expression on invasion of cancer cells.METHODS: We designed the nucleotide sequence of siRNA corresponding to 5' non-coding and coding sequence of E-cadherin. 21-nucleotide dssiRNA was synthesized by in vitro transcription with Ambion Silencer TM siRNA Construction Kit. siRNA was transfected into gastric cancer MKN45 using TransMessenger transfection Kit. RT-PCR and immunofluorescent assay were used to investigate the inhibition of the expression of mutated Ecadherin. Invasive ability of cancer cells was determined by Transwell assay.RESULTS: The synthesis of E-cadherin mRNA rather than protein expression was suppressed dramatically 7 d after interference. Decreased protein expression was observed on d 10 after interference. On d 11, invasion ability was enhanced significantly.CONCLUSION: siRNA targeted at non-coding and coding sequence of E-cadherin showed significant inhibition on mRNA and protein expression. Inhibited E-cadherin expression results in increased invasion ability of cancer cells.

  1. Gain of oncogenic function of p53 mutants regulates E-cadherin expression uncoupled from cell invasion in colon cancer cells.

    Science.gov (United States)

    Roger, Lauréline; Jullien, Laurent; Gire, Véronique; Roux, Pierre

    2010-04-15

    Mutations in the p53 tumour suppressor gene are associated clinically with tumour progression and metastasis. Downregulation of the E-cadherin cell-cell adhesion molecule is a key event for epithelial to mesenchymal transition (EMT) in tumour progression. Here, we show that wild-type p53 induced to adopt a mutant conformation, and hot-spot p53 mutants, which are both transcriptionally inactive, downregulate E-cadherin expression in the colon carcinoma cell line HCT116. Downregulation of E-cadherin occurred concomitantly with the upregulation of Slug and Zeb-1, transcriptional factors known to repress E-cadherin gene expression. In addition, knockdown of Slug and Zeb-1 expression diminished p53-mediated E-cadherin repression. Knocking down endogenous mutant p53 in MDA-MB-231 and SW620 cancer cell lines lacking E-cadherin protein restored the expression of E-cadherin. Complete loss of E-cadherin expression in HCT116 cells induced morphological alterations along with upregulation of vimentin, a mesenchymal marker. These changes characteristic of the EMT phenotype were, however, not sufficient to confer invasiveness in a three-dimensional matrix. Downregulation of E-cadherin by mutant p53 was not required to promote the invasive phenotype induced by inactivation of p53. These findings indicate that independent control of E-cadherin expression and cell motility could be essential molecular events in p53 mutant-induced invasive phenotypes.

  2. Cdc6 expression is induced by HPV16 E6 and E7 oncogenes and represses E-cadherin expression.

    Science.gov (United States)

    Faghihloo, E; Sadeghizadeh, M; Shahmahmoodi, S; Mokhtari-Azad, T

    2016-11-11

    Cervical cancer is one of the most common cancers in women worldwide, and its development is related to two viral oncoproteins E6 and E7 from high-risk human papillomaviruses. Aberrant expression of E-cadherin is associated with epithelial-to-mesenchymal transition (EMT), and it is frequently seen in cervical cancer. However, the underlying mechanisms involved in E-cadherin suppression in cervical cancer are not clear. We studied the effects of human papillomavirus 16 (HPV16) E6 and E7 on E-cadherin and Cdc6 (cell division cycle 6) expression in the HCT-116 cell line. We also assessed the relationship between Cdc6 and E-cadherin expression in cells expressing HPV16 E6 and E7 proteins. The results showed that HPV16 E6 and E7 proteins reduce E-cadherin expression, and HPV16 E6-expressing cells undergo a more profound suppression of E-cadherin compared with cells expressing HPV16 E7. Our results also revealed that HPV16 E6 and E7 oncoproteins induce Cdc6 expression, whereas suppression of Cdc6 protein by short hairpin RNA restores E-cadherin expression. Induction of Cdc6 expression in HCT-116 cells was greater with E6 than with E7, a finding that was consistent with the corresponding changes in E-cadherin expression. These observations suggest that Cdc6 overexpression is an important factor for E-cadherin reduction in cells expressing HPV16 E6 and E7 proteins and may have an important role in the metastasis of HPV-associated cancers.Cancer Gene Therapy advance online publication, 11 November 2016; doi:10.1038/cgt.2016.51.

  3. Octamer-binding protein 4 affects the cell biology and phenotypic transition of lung cancer cells involving β-catenin/E-cadherin complex degradation.

    Science.gov (United States)

    Chen, Zhong-Shu; Ling, Dong-Jin; Zhang, Yang-De; Feng, Jian-Xiong; Zhang, Xue-Yu; Shi, Tian-Sheng

    2015-03-01

    Clinical studies have reported evidence for the involvement of octamer‑binding protein 4 (Oct4) in the tumorigenicity and progression of lung cancer; however, the role of Oct4 in lung cancer cell biology in vitro and its mechanism of action remain to be elucidated. Mortality among lung cancer patients is more frequently due to metastasis rather than their primary tumors. Epithelial‑mesenchymal transition (EMT) is a prominent biological event for the induction of epithelial cancer metastasis. The aim of the present study was to investigate whether Oct4 had the capacity to induce lung cancer cell metastasis via the promoting the EMT in vitro. Moreover, the effect of Oct4 on the β‑catenin/E‑cadherin complex, associated with EMT, was examined using immunofluorescence and immunoprecipitation assays as well as western blot analysis. The results demonstrated that Oct4 enhanced cell invasion and adhesion accompanied by the downregulation of epithelial marker cytokeratin, and upregulation of the mesenchymal markers vimentin and N‑cadherin. Furthermore, Oct4 induced EMT of lung cancer cells by promoting β‑catenin/E‑cadherin complex degradation and regulating nuclear localization of β‑catenin. In conclusion, the present study indicated that Oct4 affected the cell biology of lung cancer cells in vitro through promoting lung cancer cell metastasis via EMT; in addition, the results suggested that the association and degradation of the β‑catenin/E‑cadherin complex was regulated by Oct4 during the process of EMT.

  4. MTA1-activated Epi-microRNA-22 regulates E-cadherin and prostate cancer invasiveness.

    Science.gov (United States)

    Dhar, Swati; Kumar, Avinash; Gomez, Christian R; Akhtar, Israh; Hancock, John C; Lage, Janice M; Pound, Charles R; Levenson, Anait S

    2017-03-01

    We have previously shown that metastasis-associated protein 1 (MTA1), a chromatin remodeler, plays an important role in prostate cancer invasiveness, likely through regulation of epithelial-to-mesenchymal transition. Here, we identified miR-22 as an epigenetic-microRNA (Epi-miR) directly induced by MTA1 and predicted to target E-cadherin. Loss-of-function and overexpression studies of MTA1 reinforced its regulatory role in miR-22 expression. MiR-22 directly targets the 3'-untranslated region of E-cadherin, and ectopic overexpression of miR-22 diminishes E-cadherin expression. Overexpression of miR-22 in prostate cancer cells promotes cell invasiveness and migration. Meta-analysis of patient tumor samples indicates a positive correlation between MTA1 and miR-22, supporting their inhibitory effect on E-cadherin expression. Our findings implicate the MTA1/Epi-miR-22/E-cadherin axis as a new epigenetic signaling pathway that promotes tumor invasion in prostate cancer. © 2017 Federation of European Biochemical Societies.

  5. Interactions between E-Cadherin and MicroRNA Deregulation in Head and Neck Cancers: The Potential Interplay

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    Thian-Sze Wong

    2014-01-01

    Full Text Available E-cadherin expression in the head and neck epithelium is essential for the morphogenesis and homeostasis of epithelial tissues. The cadherin-mediated cell-cell contacts are required for the anchorage-dependent growth of epithelial cells. Further, survival and proliferation require physical tethering created by proper cell-cell adhesion. Otherwise, the squamous epithelial cells will undergo programmed cell death. Head and neck cancers can escape from anoikis and enter into the epithelial-mesenchymal transition stages via the modulation of E-cadherin expression with epigenetic mechanisms. At epigenetic level, gene expression control is not dependent on the DNA sequence. In the context of E-cadherin regulation in head and neck cancers, 2 major mechanisms including de novo promoter hypermethylation and microRNA dysregulation are most extensively studied. Both of them control E-cadherin expression at transcription level and subsequently hinder the overall E-cadherin protein level in the head and neck cancer cells. Increasing evidence suggested that microRNA mediated E-cadherin expression in the head and neck cancers by directly/indirectly targeting the transcription suppressors of E-cadherin, ZEB1 and ZEB2.

  6. Interactions between E-cadherin and microRNA deregulation in head and neck cancers: the potential interplay.

    Science.gov (United States)

    Wong, Thian-Sze; Gao, Wei; Chan, Jimmy Yu-Wai

    2014-01-01

    E-cadherin expression in the head and neck epithelium is essential for the morphogenesis and homeostasis of epithelial tissues. The cadherin-mediated cell-cell contacts are required for the anchorage-dependent growth of epithelial cells. Further, survival and proliferation require physical tethering created by proper cell-cell adhesion. Otherwise, the squamous epithelial cells will undergo programmed cell death. Head and neck cancers can escape from anoikis and enter into the epithelial-mesenchymal transition stages via the modulation of E-cadherin expression with epigenetic mechanisms. At epigenetic level, gene expression control is not dependent on the DNA sequence. In the context of E-cadherin regulation in head and neck cancers, 2 major mechanisms including de novo promoter hypermethylation and microRNA dysregulation are most extensively studied. Both of them control E-cadherin expression at transcription level and subsequently hinder the overall E-cadherin protein level in the head and neck cancer cells. Increasing evidence suggested that microRNA mediated E-cadherin expression in the head and neck cancers by directly/indirectly targeting the transcription suppressors of E-cadherin, ZEB1 and ZEB2.

  7. Suppression of E-cadherin mediates gallotannin induced apoptosis in Hep G2 hepatocelluar carcinoma cells.

    Science.gov (United States)

    Han, Hee Jeong; Kwon, Hee Young; Sohn, Eun Jung; Ko, Hyunsuk; Kim, Bogeun; Jung, Kwon; Lew, Jae Hwan; Kim, Sung-Hoon

    2014-01-01

    Though gallotannin was known to have anti-oxidant and antitumor activity, the underlying antitumor mechanism of gallotannin still remains unclear. Thus, in the present study, antitumor mechanism of gallotannin was elucidated in hepatocellular carcinoma cells. Gallotannin significantly exerted cytotoxicity against Hep G2 and Chang hepatocellular carcinoma cells with the accumulation of the sub-G1 population and increase of terminal deoxynucleotidyltransferasedUTP nick end labeling (TUNEL) positive cells as an apoptotic feature. Also, gallotannin attenuated the expression of pro-caspase9, pro-caspase3, Bcl2 and integrin β1 and cleaved poly(ADP)-ribose polymerase (PARP) in Hep G2 and Chang cancer cells. Furthermore, gallotannin suppressed cell repair motility by wound healing assay and also inhibited cell adhesion in Hep G2 cells. Of note, gallotannin attenuated the expression of epithelial cadherin (E-cadherin) to form cell-cell adhesion from the early stage, and also beta-catenin at late phase in Hep G2 cells. Consistently, Immunofluorescence assay showed that E-cadherin or β-catenin expression was suppressed in a time dependent manner by gallotannin. Furthermore, silencing of E-cadherin by siRNA transfection method enhanced PAPR cleavage, caspase 3 activation and sub G1 population and attenuated the cell adhesion induced by gallotannin in Hep G2 cells. Overall, our findings demonstrate that the disruption of cell adhesion junction by suppression of E-cadherin mediates gallotannin enhanced apoptosis in Hep G2 liver cancer cells.

  8. Modulation of N-glycosylation by mesalamine facilitates membranous E-cadherin expression in colon epithelial cells.

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    Khare, Vineeta; Lang, Michaela; Dammann, Kyle; Campregher, Christoph; Lyakhovich, Alex; Gasche, Christoph

    2014-01-15

    Genome wide association studies have implicated intestinal barrier function genes in the pathogenesis of ulcerative colitis. One of such loci CDH1, encoding E-cadherin, a transmembrane glycoprotein with known tumor suppressor functions, is also linked to the susceptibility to colorectal cancer. Loss of membranous E-cadherin expression is common in both colitis and cancer. We have recently demonstrated that mesalamine (5-ASA); the anti-inflammatory drug used to treat ulcerative colitis, induces membranous expression of E-cadherin and increases intercellular adhesion. Using colorectal cancer epithelial cells with aberrant E-cadherin expression, we investigated the mechanism underlying such an effect of 5-ASA. Post-translational modification of E-cadherin glycosylation was analyzed by biotin/streptavidin detection of sialylated glycoproteins. GnT-III (N-acetylglucosaminyltransferase III) expression was assessed by qRT-PCR, Western blot and immunofluorescence. GnT-III activity was analyzed by reactivity with E-4/L-4-PHA. Expression, localization and interaction of E-cadherin and β-catenin were analyzed by Western blot, immunocytochemistry and RNA interference. 5-ASA activity modulated E-cadherin glycosylation and increased both mRNA and protein levels of GnT-III and its activity as detected by increased E4-lectin reactivity. Intestinal APC(Min) polyps in mice showed low expression of GnT-III and 5-ASA was effective in increasing its expression. The data demonstrated that remodeling of glycans by GnT-III mediated bisect glycosylation, contributes to the membranous retention of E-cadherin by 5-ASA; facilitating intercellular adhesion. Induction of membranous expression of E-cadherin by 5-ASA is a novel mechanism for mucosal healing in colitis that might impede tumor progression by modulation of GnT-III expression.

  9. The E-cadherin repressor slug and progression of human extrahepatic hilar cholangiocarcinoma

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    Wang Xin-sheng

    2010-07-01

    Full Text Available Abstract Objectives This study explored the expression and function of Slug in human extrahepatic hilar cholangiocarcinoma (EHC to identify its role in tumor progression. Methods The expression of Snail and Slug mRNA in 52 human tissue samples of EHC was investigated. The mRNA of Snail and Slug were quantified using reverse transcriptase-PCR, and correlations with E-cadherin expression and clinicopathological factors were investigated. We then investigated transfection of Slug cDNA in endogenous E-cadherin-positive human EHC FRH0201 cells, selectively induced the loss of E-cadherin protein expression, and then small interfering RNA (siRNA for inhibition of Slug expression in endogenous Slug-positive human EHC QBC939 cells, selectively induced the loss of Slug protein expression. A Boyden chamber transwell assay was used for invasion. Results Slug mRNA was overexpressed in 18 cases (34.6% of EHC compared with adjacent noncancerous tissue. E-Cadherin protein expression determined in the same 52 cases by immunohistochemistry was significantly down-regulated in those cases with Slug mRNA overexpression (P = 0.0001. The tumor and nontumor ratio of Slug mRNA was correlated with nodal metastasis(p = 0.0102, distant metastasis (p = 0.0001and Survival time(p = 0.0443. However, Snail mRNA correlated with neither E-cadherin expression nor tumor invasiveness. By inhibiting Slug expression by RNA interference, we found that reduced Slug levels upregulated E-cadherin and decreased invasion in QBC939 cell. When the QBC939 cells was infected with Slug cDNA,, significant E-cadherin was downregulated and increased invasion in QBC939 cell. Conclusions The results suggested that Slug expression plays an important role in both the regulation of E-cadherin expression and in the acquisition of invasive potential in human EHC. Slug is possibly a potential target for an antitumor therapy blocking the functions of invasion and metastasis in human EHCs.

  10. SERUM SOLUBLE E CADHERIN LEVEL IN PATIENTS WITH ENDOMETRIOSIS

    Institute of Scientific and Technical Information of China (English)

    傅晨薇; 郎景和

    2002-01-01

    Objective.To investigate the serum sE cadherin level in patients with endometriosis and the alterations of that level in healthy control during the menstrual cycle.Methods.Thirty two patients with endometriosis and 30 healthy women were tested for serum sE cadherin levels by enzyme linked immunosorbent assay.Results.The serum sE cadherin levels in healthy control did not vary throughout the menstrual cycle,which were lower than those in patients with endometriosis.Conclusions.E cadherin might be involved in endometrial shedding during menstruation in endometriosis patients.The serum sE cadherin assay might be helpful as a serum marker for the diagnosis and management of endometriosis.

  11. Zebrafish teeth as a model for repetitive epithelial morphogenesis: dynamics of E-cadherin expression

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    Sanders Ellen

    2010-06-01

    Full Text Available Abstract Background The development of teeth is the result of interactions between competent mesenchyme and epithelium, both of which undergo extensive morphogenesis. The importance of cell adhesion molecules in morphogenesis has long been acknowledged but remarkably few studies have focused on the distribution and function of these molecules in tooth development. Results We analyzed the expression pattern of an important epithelial cadherin, E-cadherin, during the formation of first-generation teeth as well as replacement teeth in the zebrafish, using in situ hybridization and whole mount immunostaining to reveal mRNA expression and protein distribution. E-cadherin was detected in every layer of the enamel organ during the different stages of tooth development, but there were slight differences between first-generation and replacement teeth in the strength and distribution of the signal. The dental papilla, which is derived from the mesenchyme, did not show any expression. Remarkably, the crypts surrounding the functional teeth showed an uneven distribution of E-cadherin throughout the pharyngeal region. Conclusions The slight differences between E-cadherin expression in zebrafish teeth and developing mouse and human teeth are discussed in the light of fundamental differences in structural and developmental features of the dentition between zebrafish and mammals. Importantly, the uninterrupted expression of E-cadherin indicates that down-regulation of E-cadherin is not required for formation of an epithelial tooth bud. Further research is needed to understand the role of other cell adhesion systems during the development of teeth and the formation of replacement teeth.

  12. A membrane fusion protein αSNAP is a novel regulator of epithelial apical junctions.

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    Nayden G Naydenov

    Full Text Available Tight junctions (TJs and adherens junctions (AJs are key determinants of the structure and permeability of epithelial barriers. Although exocytic delivery to the cell surface is crucial for junctional assembly, little is known about the mechanisms controlling TJ and AJ exocytosis. This study was aimed at investigating whether a key mediator of exocytosis, soluble N-ethylmaleimide sensitive factor (NSF attachment protein alpha (αSNAP, regulates epithelial junctions. αSNAP was enriched at apical junctions in SK-CO15 and T84 colonic epithelial cells and in normal human intestinal mucosa. siRNA-mediated knockdown of αSNAP inhibited AJ/TJ assembly and establishment of the paracellular barrier in SK-CO15 cells, which was accompanied by a significant down-regulation of p120-catenin and E-cadherin expression. A selective depletion of p120 catenin effectively disrupted AJ and TJ structure and compromised the epithelial barrier. However, overexpression of p120 catenin did not rescue the defects of junctional structure and permeability caused by αSNAP knockdown thereby suggesting the involvement of additional mechanisms. Such mechanisms did not depend on NSF functions or induction of cell death, but were associated with disruption of the Golgi complex and down-regulation of a Golgi-associated guanidine nucleotide exchange factor, GBF1. These findings suggest novel roles for αSNAP in promoting the formation of epithelial AJs and TJs by controlling Golgi-dependent expression and trafficking of junctional proteins.

  13. Expression of TGF-β1, Snail, E-cadherin and N-cadherin in Gastric Cancer and Its Significance

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    OBJECTIVE To investigate the expression of TGF-β1, Snail, E-cadherin and N-cadherin in gastric cancer (GC), and to examine its relationship to malignant features of the tumors.METHODS The expression of TGF-β1, Snail, E-cadherin and N-cadherin proteins was detected in GC and adjacent tissues by immunohistochemical staining, and compared with the clinico- pathological data.RESULTS Positive rates of expression for TGF-β1, Snail, E-cadherin and N-cadherin were 63.5%, 83.3%, 37.5% and 44.8% in GC, and 28.8%,41.3%, 100%, 11.3% in adjacent tissues, respectively. The expression of all four proteins showed a significant difference between the GCs and adjacent tissues (P<0.05). The positive rate of TGF-β1, Snail and N-cadherin, or the negative rate of E-cadherin expression was significantly related to the differentiated degree, histological type, invasion and metastasis of GC. In addition, the expression of N-cadherin was positively related to that of TGF-β1,but negatively related to that of E-cadherin. There was negative correlation between expression of E-cadherin and TGF-β1 and Snail in GC (P<0.05).CONCLUSION The over-expression of TGF-β1 and Snail and decreased expression of E-cadherin and the abnormal expression of N-cadherin were involved in the process of invasion and metastasis of GC. The data showed that E-cadherin might switch to N-cadherin. TGF-β1 and Snail might play a fundamental role in the process.

  14. Association of E-cadherin and β-catenin with metastasis in nasopharyngeal carcinoma

    Institute of Scientific and Technical Information of China (English)

    李智; 任艺; 林素暇; 梁英杰; 梁惠珍

    2004-01-01

    Background This study was designed to detect methylation of E-cadherin gene promoter and gene mutation of β-catenin in exon 3 and their expression of protein and mRNA in primary tumor and lymph node metastatic tumor of nasopharyngeal carcinoma (NPC), and investigate the mechanism of invasion and metastasis of neoplastic cells in NPC.Methods Fourty-two fresh biopsy samples were taken from untreated NPC patients at the Affiliated Hospital of Sun Yat-sen Medical College, Sun Yat-sen University, Guangzhou, China during the period of 1999-2002. Among them 21 were taken from primary tumors and the other 21 from lymph node metastatic tumors. The gene promoter methylation of E-cadherin was detected by methylation-specific PCR (MSP). The mutation in exon 3 of β-catenin was detected by direct sequencing analysis. RT-PCR, Western blot and immunohistochemical staining were used to detect the mRNA and protein expression patterns in both primary and metastatic tumors of NPC. Results Down-regulated expression of E-cadherin in metastatic tumor was compared with that in primary tumor. Reduced expression of E-cadherin was found to be correlated with lymph node metastatic tumor of NPC (P=0.004); but there was no obvious correlation between primary and metastatic tumors in the expression of β-catenin (P=0.698). The mRNA expression level of E-cadherin in metastatic tumors decreased significantly compared with that in primary tumors. However, little change was observed in the mRNA level of β-catenin in different tumor tissues. Only 4 samples (19.1%) displayed gene promoter methylation of E-cadherin in primary tumor and 10 samples (47.6%) showed methylated form of E-cadherin. The gene promoter methylation of E-cadherin was more common in metastatic tumor than in primary tumor of NPC (P=0.024). Only 2 (4.76%) of the 42 samples showed mutations in exon 3 of β-catenin at 41 (T41A, ACCGCC) and codon 47 (S47T, AGTACT). The cytoplasmic and nuclear expression of β-catenin in tumor

  15. E-cadherin endocytosis regulates the activity of Rap1: a traffic light GTPase at the crossroads between cadherin and integrin function.

    Science.gov (United States)

    Balzac, Fiorella; Avolio, Maria; Degani, Simona; Kaverina, Irina; Torti, Mauro; Silengo, Lorenzo; Small, J Victor; Retta, Saverio Francesco

    2005-10-15

    The coordinate modulation of cadherin and integrin functions plays an essential role in fundamental physiological and pathological processes, including morphogenesis and cancer. However, the molecular mechanisms underlying the functional crosstalk between cadherins and integrins are still elusive. Here, we demonstrate that the small GTPase Rap1, a crucial regulator of the inside-out activation of integrins, is a target for E-cadherin-mediated outside-in signaling. In particular, we show that a strong activation of Rap1 occurs upon adherens junction disassembly that is triggered by E-cadherin internalization and trafficking along the endocytic pathway. By contrast, Rap1 activity is not influenced by integrin outside-in signaling. Furthermore, we demonstrate that the E-cadherin endocytosis-dependent activation of Rap1 is associated with and controlled by an increased Src kinase activity, and is paralleled by the colocalization of Rap1 and E-cadherin at the perinuclear Rab11-positive recycling endosome compartment, and the association of Rap1 with a subset of E-cadherin-catenin complexes that does not contain p120ctn. Conversely, Rap1 activity is suppressed by the formation of E-cadherin-dependent cell-cell junctions as well as by agents that inhibit either Src activity or E-cadherin internalization and intracellular trafficking. Finally, we demonstrate that the E-cadherin endocytosis-dependent activation of Rap1 is associated with and is required for the formation of integrin-based focal adhesions. Our findings provide the first evidence of an E-cadherin-modulated endosomal signaling pathway involving Rap1, and suggest that cadherins may have a novel modulatory role in integrin adhesive functions by fine-tuning Rap1 activation.

  16. Liver protects metastatic prostate cancer from induced death by activating E-cadherin signaling.

    Science.gov (United States)

    Ma, Bo; Wheeler, Sarah E; Clark, Amanda M; Whaley, Diana L; Yang, Min; Wells, Alan

    2016-11-01

    Liver is one of the most common sites of cancer metastasis. Once disseminated, the prognosis is poor as these tumors often display generalized chemoresistance, particularly for carcinomas that derive not from the aerodigestive tract. When these cancers seed the liver, the aggressive cells usually undergo a mesenchymal to epithelial reverting transition that both aids colonization and renders the tumor cells chemoresistant. In vitro studies demonstrate that hepatocytes drive this phenotypic shift. However, the in vivo evidence and the molecular signals that protect these cells from induced death are yet to be defined. Herein, we report that membrane surface E-cadherin-expressing prostate cancer cells were resistant to cell death by chemotherapeutic drugs but E-cadherin null cells or those expressing E-cadherin only in the cytoplasm were sensitive to death signals and chemotherapies both in vitro and in vivo. While cell-cell E-cadherin ligandation reduced mitogenesis, this chemoprotection was proliferation-independent as killing of both 5-ethynyl-2'-deoxyuridine-positive (or Ki67(+) ) and 5-ethynyl-2'-deoxyuridine-negative (Ki67(-) ) cells was inversely related to membrane-bound E-cadherin. Inhibiting the canonical survival kinases extracellular signal-regulated protein kinases, protein kinase B, and Janus kinase, which are activated by chemotherapeutics in epithelial cell-transitioned prostate cancer, abrogated the chemoresistance both in cell culture and in animal models of metastatic cancer. For disseminated tumors, protein kinase B disruption in itself had no effect on tumor survival but was synergistic with chemotherapy, leading to increased killing.

  17. Clinicopathologic Correlations of E-cadherin and Prrx-1 Expression Loss in Hepatocellular Carcinoma

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    Kijong Yi

    2016-09-01

    Full Text Available Background Developing predictive markers for hepatocellular carcinoma (HCC is important, because many patients experience recurrence and metastasis. Epithelial to mesenchymal transition (EMT is a developmental process that plays an important role during embryogenesis and also during cancer metastasis. Paired-related homeobox protein 1 (Prrx-1 is an EMT inducer that has recently been introduced, and its prognostic significance in HCC is largely unknown. Methods Tissue microarray was constructed using surgically resected primary HCCs from 244 cases. Immunohistochemical staining of E-cadherin and Prrx-1 was performed. The correlation between E-cadherin loss and Prrx-1 expression, as well as other clinicopathologic factors, was evaluated. Results E-cadherin expression was decreased in 96 cases (39.4%. Loss of E-cadherin correlated with a higher recurrence rate (p 40% were independent prognostic factors for shorter overall survival. Conclusions Prrx-1 was expressed in small portions of HCCs but not in normal livers. Additional studies with a large number of Prrx-1-positive cases are required to confirm the results of this study.

  18. E-cadherin and c-Met expression in actinic cheilits and lip squamous cell carcinoma

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    A Martínez

    2011-12-01

    Full Text Available Objective: The aim of this study was to assess epithelial expression of E-cadherin and c-Met in normal lip, in actinic cheilitis and lip squamous cell carcinoma. Study Design: Biopsies of normal lip vermillion (NL, n=18, actinic cheilitis (AC, n=37, and lip SCC (n=22 were processed for E-cadherin and c-Met immunodetection. Epithelial and tumor cell expression was scored for each sample considering staining intensity and percentage. Results: E-cadherin expression was significantly reduced in AC and lip SCC as compared to normal lip (P<0.05, with a significant reduction in lip SCC as compared to AC (P=0.003. Expression of c-Met was significantly higher in AC and lip SCC as compared to NL (P<0.05, with a significant increase in lip SCC as compared to AC (P<0.0001. Conclusion: The results showed that epithelial E-cadherin expression is reduced and c-Met expression is increased as lip carcinogenesis progresses, suggesting that these proteins may be useful markers of malignant transformation.

  19. Acute and chronic cadmium exposure promotes E-cadherin degradation in MCF7 breast cancer cells.

    Science.gov (United States)

    Ponce, Esmeralda; Louie, Maggie C; Sevigny, Mary B

    2015-10-01

    Cadmium is an environmental carcinogen that usually enters the body at minute concentrations through diet or cigarette smoke and bioaccumulates in soft tissues. In past studies, cadmium has been shown to contribute to the development of more aggressive cancer phenotypes including increased cell migration and invasion. This study aims to determine if cadmium exposure-both acute and chronic-contributes to breast cancer progression by interfering with the normal functional relationship between E-cadherin and β-catenin. An MCF7 breast cancer cell line (MCF7-Cd) chronically exposed to 10(-7)  M CdCl2 was previously developed and used as a model system to study chronic exposures, whereas parental MCF7 cells exposed to 10(-6)  M CdCl2 for short periods of time were used to study acute exposures. Cadmium exposure of MCF7 cells led to the degradation of the E-cadherin protein via the ubiquitination pathway. This resulted in fewer E-cadherin/β-catenin complexes and the relocation of active β-catenin to the nucleus, where it interacted with transcription factor TCF-4 to modulate gene expression. Interestingly, only cells chronically exposed to cadmium showed a significant decrease in the localization of β-catenin to the plasma membrane and an increased distance between cells. Our data suggest that cadmium exposure promotes breast cancer progression by (1) down-regulating E-cadherin, thus decreasing the number of E-cadherin/β-catenin adhesion complexes, and (2) enhancing the nuclear translocation of β-catenin to increase expression of cancer-promoting proteins (i.e., c-Jun and cyclin D1).

  20. E-cadherin interactions are required for Langerhans cell differentiation

    Science.gov (United States)

    Mayumi, Nobuko; Watanabe, Eri; Norose, Yoshihiko; Watari, Eiji; Kawana, Seiji; Geijtenbeek, Teunis B H; Takahashi, Hidemi

    2013-01-01

    Human skin contains the following two distinct DC subsets: (i) Langerhans cells (LCs), expressing Langerin but not DC-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN), are predominantly localized in the epidermis; and (ii) dermal DCs, expressing DC-SIGN but not Langerin, are observed mainly in the dermis. It is not known whether localization in the epidermis provides cues for LC differentiation. Here, we show that E-cadherin expressed by epidermal keratinocytes (KCs) is crucial for differentiation of LCs. Monocytes differentiated into LC-like cells in presence of IL-4, GM-CSF, and TGF-β1. However, these LC-like cells expressed not only Langerin but also DC-SIGN. Notably, co-culturing of these LC-like cells with KCs expressing E-cadherin or recombinant E-cadherin strongly decreased expression of DC-SIGN and further induced a phenotype similar to purified epidermal LCs. Moreover, pretreatment of LC-like cells with anti-E-cadherin-specific antibody completely abolished their Langerin expression, indicating the requirement of E-cadherin–E-cadherin interactions for the differentiation into Langerin+ cells. These findings suggest that E-cadherin expressed by KCs provide environmental cues that induce differentiation of LCs in the epidermis. PMID:23135957

  1. E-cadherin can replace N-cadherin during secretory-stage enamel development.

    Science.gov (United States)

    Guan, Xiaomu; Bidlack, Felicitas B; Stokes, Nicole; Bartlett, John D

    2014-01-01

    N-cadherin is a cell-cell adhesion molecule and deletion of N-cadherin in mice is embryonic lethal. During the secretory stage of enamel development, E-cadherin is down-regulated and N-cadherin is specifically up-regulated in ameloblasts when groups of ameloblasts slide by one another to form the rodent decussating enamel rod pattern. Since N-cadherin promotes cell migration, we asked if N-cadherin is essential for ameloblast cell movement during enamel development. The enamel organ, including its ameloblasts, is an epithelial tissue and for this study a mouse strain with N-cadherin ablated from epithelium was generated. Enamel from wild-type (WT) and N-cadherin conditional knockout (cKO) mice was analyzed. μCT and scanning electron microscopy showed that thickness, surface structure, and prism pattern of the cKO enamel looked identical to WT. No significant difference in hardness was observed between WT and cKO enamel. Interestingly, immunohistochemistry revealed the WT and N-cadherin cKO secretory stage ameloblasts expressed approximately equal amounts of total cadherins. Strikingly, E-cadherin was not normally down-regulated during the secretory stage in the cKO mice suggesting that E-cadherin can compensate for the loss of N-cadherin. Previously it was demonstrated that bone morphogenetic protein-2 (BMP2) induces E- and N-cadherin expression in human calvaria osteoblasts and we show that the N-cadherin cKO enamel organ expressed significantly more BMP2 and significantly less of the BMP antagonist Noggin than did WT enamel organ. The E- to N-cadherin switch at the secretory stage is not essential for enamel development or for forming the decussating enamel rod pattern. E-cadherin can substitute for N-cadherin during these developmental processes. Bmp2 expression may compensate for the loss of N-cadherin by inducing or maintaining E-cadherin expression when E-cadherin is normally down-regulated. Notably, this is the first demonstration of a natural endogenous

  2. E-cadherin can replace N-cadherin during secretory-stage enamel development.

    Directory of Open Access Journals (Sweden)

    Xiaomu Guan

    Full Text Available BACKGROUND: N-cadherin is a cell-cell adhesion molecule and deletion of N-cadherin in mice is embryonic lethal. During the secretory stage of enamel development, E-cadherin is down-regulated and N-cadherin is specifically up-regulated in ameloblasts when groups of ameloblasts slide by one another to form the rodent decussating enamel rod pattern. Since N-cadherin promotes cell migration, we asked if N-cadherin is essential for ameloblast cell movement during enamel development. METHODOLOGY/PRINCIPAL FINDINGS: The enamel organ, including its ameloblasts, is an epithelial tissue and for this study a mouse strain with N-cadherin ablated from epithelium was generated. Enamel from wild-type (WT and N-cadherin conditional knockout (cKO mice was analyzed. μCT and scanning electron microscopy showed that thickness, surface structure, and prism pattern of the cKO enamel looked identical to WT. No significant difference in hardness was observed between WT and cKO enamel. Interestingly, immunohistochemistry revealed the WT and N-cadherin cKO secretory stage ameloblasts expressed approximately equal amounts of total cadherins. Strikingly, E-cadherin was not normally down-regulated during the secretory stage in the cKO mice suggesting that E-cadherin can compensate for the loss of N-cadherin. Previously it was demonstrated that bone morphogenetic protein-2 (BMP2 induces E- and N-cadherin expression in human calvaria osteoblasts and we show that the N-cadherin cKO enamel organ expressed significantly more BMP2 and significantly less of the BMP antagonist Noggin than did WT enamel organ. CONCLUSIONS/SIGNIFICANCE: The E- to N-cadherin switch at the secretory stage is not essential for enamel development or for forming the decussating enamel rod pattern. E-cadherin can substitute for N-cadherin during these developmental processes. Bmp2 expression may compensate for the loss of N-cadherin by inducing or maintaining E-cadherin expression when E-cadherin is

  3. Alteration of cadherin isoform expression and inhibition of gap junctions in stomach carcinoma cells

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    To explore cell malignant phenotype correlated changes of cell surface adhesion molecules and cell-cell communication in carcinogenesis, human stomach transformed and cancer cell lines were investigated. Expressions of E-cadherin, N-cadherin, ?-catenin, ?-catenin as well as gap junction (GJ) protein Cx32 were studied by utilization of immunoblotting, immunocytochemical and fluorescent dye transfer methods. Mammalian normal stomach mucosal cells expressed E-cadherin but not N-cadherin. E-cadherin immunofluorescence was detected at cell membranous adherens junctions (AJ) where colocalization with immunofluorescent staining of inner surface adhesion plaque proteins ?- and ?-catenins was observed. The existence of E-cadherin/ catenin (?-, ?-) protein complexes as AJ was suggested. In transformed and stomach cancer cells E-cadherin was inhibited, instead, N-cadherin was expressed and localized at membranous AJ where co-staining with ?- and ?-catenin fluorescence was observed. Formation of N-cadherin/catenin (?-, ?-) protein complex at AJs of transformed and cancer cells was suggested. The above observations were further supported by immunoblotting results. Normal stomach muscosal and transformed cells expressed Cx32 at membranous GJ and were competent of gap junction communication (GJIC). In stomach cancer cells, Cx32 was inhibited and GJIC was defective. The results suggested that changes of signal pathways mediated by both cell adhesion and cell communication systems are associated intracellular events of stomach carcinogenesis. The alteration of cadherin isoform from E- to N-cadherin in transformed and stomach cancer cells is the first report.

  4. E-cadherin promotes proliferation of human ovarian cancer cells in vitro via activating MEK/ERK pathway

    Institute of Scientific and Technical Information of China (English)

    Ling-ling DONG; Lian LIU; Chun-hong MA; Ji-sheng LI; Chao DU; Shan XU; Li-hui HAN; Li LI; Xiu-wen WANG

    2012-01-01

    Aim:E-cadherin is unusually highly expressed in most ovarian cancers.This study was designed to investigate the roles of E-cadherin in the carcinogenesis and progression of ovarian cancers.Methods:Human ovarian adenocarcinoma cell line SKOV-3 was examined.E-cadherin gene CDH1 in SKOV-3 cells was knocked down via RNA interference (RNAi),and the resultant variation of biological behavior was observed using CCK-8 and colony formation experiment.E-cadherin-mediated Ca2+-dependent cell-cell adhesion was used to study the mechanisms underlying the effects of E-cadherin on the proliferation and survival of SKOV-3 cells.The expression levels of E-cadherin,extracellular signal-related kinase (ERK),phosphorylated ERK (P-ERK) were measured using Western blot assays.Results:Transfection with CDH1-siRNA for 24-96 h significantly suppressed the growth and proliferation of SKOV-3 cells.E-cadhednmediated calcium-dependent cell-cell adhesion of SKOV-3 cells resulted in a rapid increase of P-ERK,but did not modify the expression of ERK protein.The phosphorylation of ERK in the cells was blocked by pretreatment with the MEK1 specific inhibitor PD98059 (50μmol/L),but not bythe PI3K inhibitor wortmannin (1μmol/L) or PKA inhibitor H89 (10 μmol/L).Conclusion:E-cadherin may function as a tumor proliferation enhancer via activating the MEK/ERK pathway in development of ovarian epithelial cancers.

  5. Snail,E-cadherin 在胃癌中的表达及意义%Expression and Significance of Snail and E-cadherin in Gastric Cancer

    Institute of Scientific and Technical Information of China (English)

    曹晓丽; 杜圣英; 李登欣; 张晴

    2013-01-01

    Objective To investigate the expression of Snail and E-cadherin protein in gastric cancer and explore their significance.Methods The expression of Snail and E-cadherin protein was detected by immunohistochemi-cal SP method in 45 cases of gastric carcinoma tissue and 20 cases of para-cancerous normal gastric tissue.Results The positive rate of Snail immunostaining in gastric carcinoma was higher than that in adjacent normal gastric tissue (P<0. 05),the positive rate of E-cadherin immunostaining in gastric cancer was lower than that in adjacent normal gastric tissue (P<0.05).The expression of Snail and E-cadherin in gastric carcinoma tissue was closely related with the depth of tumor invasion,differentiatial degree,clinical stage,lymph node metastases and distant metastases (P<0.05).There was negative correlation between the expression of Snail and E-cadherin protein in gastric carcinoma(P<0.05).Conclusion The abnormal expression of Snail and E-cadherin might be important biological markers for malignant transformation , invasion and metastasis of gastric carcinoma .Co-detection of Snail and E-cadherin has significant effect on predicting the degree of malignancy and prognosis of gastric cancer .%  目的观察锌指结合蛋白(Snail)和上皮性钙粘附蛋白E-cadherin在胃癌组织中的表达,并探讨其意义.方法采用免疫组化SP法检测45例胃癌患者肿瘤组织和20例癌旁正常胃组织中Snail,E-cadherin蛋白的表达.结果胃癌组织中Snail阳性表达率明显高于癌旁正常胃组织(P<0.05),胃癌组织中E-cadherin阳性表达率显著低于癌旁正常胃组织(P<0.05);Snail和E-cad表达均与胃癌的分化程度、浸润深度、临床分期、淋巴结转移、是否有远处器官转移密切相关(P<0.05);Snail与E-cadherin在胃癌组织中的表达呈显著负相关(P<0.05).结论 Snail,E-cadherin的异常表达可能是胃黏膜发生恶性转变及胃癌发生侵袭转移的重要生物学标志,联合检测两

  6. Expression and significance of E-cadherin, N-cadherin, transforming growth factor-β1 and Twist in prostate cancer

    Institute of Scientific and Technical Information of China (English)

    Ge-Liang Liu; Han-Jie Yang; Tian Liu; Yun-Zhao Lin

    2014-01-01

    Objective: To study the expression of E-cadherin, N-cadherin, TGF-1 and Twist protein and investigate its significance in the occurrence and development of prostate cancer. Methods:The expression of E-cadherin, N-cadherin, TGF-1 and Twist protein in 59 prostate cancer tissues and 21 adjacent tissues were detected by immunohistochemical SABC staining, and the correlation with clinicopathological features was analyzed. Results: Positive rates of E-cadherin, N-cadherin, TGF-1 and Twist were 32.2%, 54.2%, 71.2% and 74.6%, respectively, in prostate cancer tissues and 85.7%, 9.52%, 19.0% and 9.52%, respectively, in cancer-adjacent tissues, with significant differences between the two groups (P20g/L group, but the positive expression of Twist was not significant between groups. The expression of E-cadherin was highly negatively correlated with that of N-cadherin and also highly negatively correlated with that of Twist. The expression of TGF-1 was correlated with those of E-cadherin, N-cadherin and Twist. Conclusions: The reduced expression of E-cadherin, abnormal expression of N-cadherin, transformation form E-cadherin to N-cadherin and the increased expression of TGF-1 and Twist play an important role in the occurrence and development of prostate cancer.

  7. O-mannosylation and N-glycosylation: two coordinated mechanisms regulating the tumour suppressor functions of E-cadherin in cancer.

    Science.gov (United States)

    Carvalho, Sandra; Oliveira, Tiago; Bartels, Markus F; Miyoshi, Eiji; Pierce, Michael; Taniguchi, Naoyuki; Carneiro, Fátima; Seruca, Raquel; Reis, Celso A; Strahl, Sabine; Pinho, Salomé S

    2016-10-04

    Dysregulation of tumor suppressor protein E-cadherin is an early molecular event in cancer. O-mannosylation profile of E-cadherin is a newly-described post-translational modification crucial for its adhesive functions in homeostasis. However, the role of O-mannosyl glycans in E-cadherin-mediated cell adhesion in cancer and their interplay with N-glycans remains largely unknown. We herein demonstrated that human gastric carcinomas exhibiting a non-functional E-cadherin display a reduced expression of O-mannosyl glycans concomitantly with increased modification with branched complex N-glycans. Accordingly, overexpression of MGAT5-mediated branched N-glycans both in gastric cancer cells and transgenic mice models led to a significant decrease of O-mannosyl glycans attached to E-cadherin that was associated with impairment of its tumour suppressive functions. Importantly, overexpression of protein O-mannosyltransferase 2 (POMT2) induced a reduced expression of branched N-glycans which led to a protective effect of E-cadherin biological functions. Overall, our results reveal a newly identified mechanism of (dys)regulation of E-cadherin that occur through the interplay between O-mannosylation and N-glycosylation pathway.

  8. Alterations of C-MYC, NKX3.1, and E-cadherin expression in canine prostate carcinogenesis

    DEFF Research Database (Denmark)

    Fonseca-Alves, Carlos E; Rodrigues, Marcela M P; de Moura, Veridiana M B D;

    2013-01-01

    therapies. In humans, the PCa frequently exhibits mutations in the C-MYC and a reduced expression of the E-cadherin and NKX3.1 proteins. This study's objective was to evaluate the NKX3.1, C-MYC, and E-cadherin expression in the canine normal prostate, benign prostatic hyperplasia (BPH), proliferative......The dog (canis lupus familiaris) is the only other species besides humans that develop spontaneous prostatic carcinomas (PCa) at a high frequency. The canine model is primarily utilized for the study of the PCa molecular mechanisms and provides a natural animal model for the study of potential...... inflammatory atrophy (PIA) and PCa and to verify differences in expression and subcellular localization of these proteins in the prostatic carcinogenesis. A tissue microarray (TMA) slide was constructed, and immunohistochemistry with antibodies raised against C-MYC, NKX3.1, E-cadherin and p63 was performed...

  9. Induction of E-cadherin+ human amniotic fluid cell differentiation into oocyte-like cells via culture in medium supplemented with follicular fluid.

    Science.gov (United States)

    Liu, Te; Huang, Yongyi; Bu, Yanzhen; Zhao, Yanhui; Zou, Gang; Liu, Zhixue

    2014-07-01

    Pluripotent human amniotic fluid cells (HuAFCs) can differentiate into various types of somatic cell in vitro. However, their differentiation into oocyte-like cells has never been described to the best of our knowledge. In the present study, differentiation of E-cadherin+ and E-cadherin- HuAFC sub-populations into oocyte-like cells was induced via culture in medium containing bovine follicular fluid and β-mercaptoethanol. The E-cadherin+ HuAFCs expressed DAZL highly. Post-induction, cells with an oocyte-like phenotype were found among the E-cadherin+ HuAFCs, expressing markers specific to germ cells and oocytes (VASA, ZP3 and GDF9) and meiosis (DMC1 and SCP3). When specific small interfering RNA (siRNA) was used to suppress E-cadherin in the E-cadherin+ HuAFCs, the levels of DAZL expression were reduced. Post-induction, the morphology of the siRNA‑E‑cadherin HuAFCs was poorer and the expression levels of germ cell-specific markers were lower compared with those of the siRNA-mock HuAFCs. Therefore, E-cadherin+ HuAFCs could be more easily induced to differentiate into oocyte-like cells by bovine follicular fluid and β-mercaptoethanol. In addition, the E-cadherin+ HuAFCs exhibited potential characteristics of DAZL protein expression, and thus it was conjectured that bovine follicular fluid acts on DAZL protein and promotes E-cadherin+ HuAFC differentiation into oocyte-like cells.

  10. Gap junctions and connexin-interacting proteins

    NARCIS (Netherlands)

    Giepmans, Ben N G

    2004-01-01

    Gap junctions form channels between adjacent cells. The core proteins of these channels are the connexins. Regulation of gap junction communication (GJC) can be modulated by connexin-associating proteins, such as regulatory protein phosphatases and protein kinases, of which c-Src is the best-studied

  11. Gap junctions and connexin-interacting proteins

    NARCIS (Netherlands)

    Giepmans, Ben N G

    2004-01-01

    Gap junctions form channels between adjacent cells. The core proteins of these channels are the connexins. Regulation of gap junction communication (GJC) can be modulated by connexin-associating proteins, such as regulatory protein phosphatases and protein kinases, of which c-Src is the

  12. Gap junctions and connexin-interacting proteins

    NARCIS (Netherlands)

    Giepmans, Ben N G

    2004-01-01

    Gap junctions form channels between adjacent cells. The core proteins of these channels are the connexins. Regulation of gap junction communication (GJC) can be modulated by connexin-associating proteins, such as regulatory protein phosphatases and protein kinases, of which c-Src is the best-studied

  13. E-cadherin、FAK、nm23-H1蛋白表达与声门上型喉癌颈淋巴结转移的相关因素研究%Expression of E-cadherin, FAK and nm23-H1 proteins in carcinoma of supraglottic larynx with lymph node metastasis

    Institute of Scientific and Technical Information of China (English)

    张靖华; 陈英武; 平金良; 徐炜; 顾栋烨

    2011-01-01

    Objective To investigate the expression ofE- cadherin, FAK (FocalAdhesion Kinase) and nm23- H1 proteins in carcinoma of supraglottic larynx with cervical lymph node metastasis. Methods Expression of E- cadherin, FAK and nm23- H1 proteins were detected by Envision two- step immunohistochemical method in 70 cases ofsupraglottic laryngeal carcinoma. The relationship ofE- cadherin, FAK and nm23- H1 expression with cervical lymph node metastasis was analyzed. Results E- cadherin and FAK were significantly correlated with cervical lymph node metastasis in supraglottic laryngeal cancer, but Nm23- Hl was not. Logistic regression showed that the diagnostic accuracy of combination of FAK expression, histological grade and T classification for cervical lymph node metastasis was 79.4%. Conclusions E- cadherin, FAK exprcssinn is significantly correlated with cerv ieal node metastasis of supraglottic carcinoma. Combination with tissue differentiation G, primary tumor staging T and FAK expression can predict cervical lymph node metastasis with high accuracy.%目的 探讨E-cadherin、FAK、nm23-H1蛋白表达与声门上型喉癌颈淋巴结转移的关系,以利于临床上预估颈淋巴结转移情况.方法 采用免疫组织化学Envision两步法检测70例声门上型喉癌中E-cadherin、FAK、nm23-H1的表达情况,结合患者临床资料分析3种免疫标志物(E-cadherin、FAK、nm23-H1蛋白)与颈淋巴结转移的相关性.结果 E-cadherin及FAK蛋白表达与颈淋巴结转移均明显相关(P<0.05),nm23-H1蛋白表达与颈淋巴结转移无明显相关(P >0.05).E-cadherin及FAK蛋白均阳性表达与颈淋巴结转移显著相关(P<0.01).肿瘤分期、远处转移、病理分化程度均与颈淋巴结转移相关(均P<0.01).原发肿瘤分期T、组织分化G、FAK被纳入Logistic回归方程,利用该方程可得颈淋巴结无转移的准确率为75.6%,颈淋巴结有转移的准确率为82.7%,总体准确率为79.4%.结论 声门上型喉癌

  14. CD44v6、E-cadherin和ki-67蛋白质与腮腺多形性腺瘤的生物学行为相关性研究%Correlation Study between Expression of CD44v6, E-cadherin and ki-67 Protein and Biological Behaviors in Parotid Gland Pleomorphic Adenoma

    Institute of Scientific and Technical Information of China (English)

    邱雪冰; 赵瑾; 徐江

    2014-01-01

    To explore the correlation between expression of CD44v6, E-cadherin,ki-67 protein and biological behavior of parotid gland pleomorphic adenoma. Immunohistochemical SP dyeing method was applied to detect CD44v6,E-cadherin and Ki-67 protein expression in pleomorphic adenoma,non-tumor tissue and malignant tumor of parotid gland.The results showed that the positive expression rate of CD44v6,E-cadherin and ki-67 was 100%,96% and 73.8% respectively in the parotid gland pleomorphic adenoma;There was a significant difference in the expression of E-cadherin and ki-67 in the parotid gland pleomorphic adenoma,malignant tissue and peripheral non-tutor tissue.There was correlation with invasion and metastasis of the parotid gland pleomorphic adenoma;The CD44v6 expression had statistical differences in the parotid gland pleomorphic adenoma and peripheral non-tutor tissue,malignant tissue and peripheral non-tutor tissue.It suggested that E-cadherin and ki-67 was associated with the biological behavior of the parotid gland pleomorphic adenoma,which could be used as aa new tutor marker to evaluate the prognosis.%为检测腮腺多形性腺瘤中CD44v6、E-cadherin和ki-67蛋白表达,以探讨其与腮腺多形性腺瘤生物学行为的相关性。应用免疫组织化学SP法染色检测腮腺多形性腺瘤组、多形性腺瘤恶变组和瘤旁非瘤组织组各组间CD44v6、E-cadherin和ki-67蛋白表达。结果显示,(1)CD44v6、E-cadherin和ki-67在腮腺多形性腺瘤组中的阳性表达率分别为100%、96%和73.8%;(2)E-cadherin和ki-67在腮腺多形性腺瘤组、多形性腺瘤恶变组和瘤周非瘤组织间的阳性表达率均有差异,其表达与腮腺多形性腺瘤的浸润转移有关;(3)CD44v6在腮腺多形性腺瘤组与瘤周非瘤组织组,多形性腺瘤恶变组与瘤周非瘤组织组中的表达有统计学差异。由此可知,E-cadherin和ki-67与腮腺多形性腺瘤的生物学行为有关,可作为新的肿瘤标志物,其

  15. Levels of soluble E-cadherin in breast, gastric, and colorectal cancers.

    Science.gov (United States)

    Repetto, Ombretta; De Paoli, Paolo; De Re, Valli; Canzonieri, Vincenzo; Cannizzaro, Renato

    2014-01-01

    Soluble E-cadherin is a 80 kDa protein fragment coming from the proteolytic cleavage of the extracellular domain of the full length epithelial cadherin, a molecule involved in cell adhesion/polarity and tissue morphogenesis. In comparison with normal epithelia, cancer cells show a decreased cadherin-mediated intercellular adhesion, and sE-cad levels normally increase in body fluids (blood and urine). This review focuses on soluble E-cadherin in sera of patients affected by three solid cancers (breast, gastric, and colorectal cancers) and how its levels correlate or not with some cancer parameters (e.g., dimension, progression, and localisation). We will describe the main proteomics approaches adopted to measure sE-cad both in vivo and in vitro and the most important findings about its behaviour in cancer dynamics.

  16. Dynamic interplay between adhesive and lateral E-cadherin dimers

    DEFF Research Database (Denmark)

    Klingelhöfer, Jörg; Laur, Oscar Y; Troyanovsky, Regina B;

    2002-01-01

    M. The disappearance of adhesive dimers was counterbalanced by an increase in Trp156-dependent lateral dimers. Increasing the calcium concentration to a normal level rapidly restored the original balance between adhesive and lateral dimers. We also present evidence that E-cadherin dimers in vivo have a short lifetime...

  17. Functional dissection of the Clostridium botulinum type B hemagglutinin complex: identification of the carbohydrate and E-cadherin binding sites.

    Directory of Open Access Journals (Sweden)

    Yo Sugawara

    Full Text Available Botulinum neurotoxin (BoNT inhibits neurotransmitter release in motor nerve endings, causing botulism, a condition often resulting from ingestion of the toxin or toxin-producing bacteria. BoNTs are always produced as large protein complexes by associating with a non-toxic protein, non-toxic non-hemagglutinin (NTNH, and some toxin complexes contain another non-toxic protein, hemagglutinin (HA, in addition to NTNH. These accessory proteins are known to increase the oral toxicity of the toxin dramatically. NTNH has a protective role against the harsh conditions in the digestive tract, while HA is considered to facilitate intestinal absorption of the toxin by intestinal binding and disruption of the epithelial barrier. Two specific activities of HA, carbohydrate and E-cadherin binding, appear to be involved in these processes; however, the exact roles of these activities in the pathogenesis of botulism remain unclear. The toxin is conventionally divided into seven serotypes, designated A through G. In this study, we identified the amino acid residues critical for carbohydrate and E-cadherin binding in serotype B HA. We constructed mutants defective in each of these two activities and examined the relationship of these activities using an in vitro intestinal cell culture model. Our results show that the carbohydrate and E-cadherin binding activities are functionally and structurally independent. Carbohydrate binding potentiates the epithelial barrier-disrupting activity by enhancing cell surface binding, while E-cadherin binding is essential for the barrier disruption.

  18. Cell division orientation is coupled to cell-cell adhesion by the E-cadherin/LGN complex

    NARCIS (Netherlands)

    Gloerich, Martijn; Bianchini, Julie M.; Siemers, Kathleen A.; Cohen, Daniel J.; Nelson, W. James

    2017-01-01

    Both cell-cell adhesion and oriented cell division play prominent roles in establishing tissue architecture, but it is unclear how they might be coordinated. Here, we demonstrate that the cell-cell adhesion protein E-cadherin functions as an instructive cue for cell division orientation. This is

  19. Characterization and significance of adhesion and junction-related proteins in mouse ovarian follicles.

    Science.gov (United States)

    Mora, Jocelyn M; Fenwick, Mark A; Castle, Laura; Baithun, Marianne; Ryder, Timothy A; Mobberley, Margaret; Carzaniga, Raffaella; Franks, Stephen; Hardy, Kate

    2012-05-01

    In the ovary, initiation of follicle growth is marked by cuboidalization of flattened granulosa cells (GCs). The regulation and cell biology of this shape change remains poorly understood. We propose that characterization of intercellular junctions and associated proteins is key to identifying as yet unknown regulators of this important transition. As GCs are conventionally described as epithelial cells, this study used mouse ovaries and isolated follicles to investigate epithelial junctional complexes (tight junctions [TJ], adherens junctions [AJ], and desmosomes) and associated molecules, as well as classic epithelial markers, by quantitative PCR and immunofluorescence. These junctions were further characterized using ultrastructural, calcium depletion and biotin tracer studies. Junctions observed by transmission electron microscopy between GCs and between GCs and oocyte were identified as AJs by expression of N-cadherin and nectin 2 and by the lack of TJ and desmosome-associated proteins. Follicles were also permeable to biotin, confirming a lack of functional TJs. Surprisingly, GCs lacked all epithelial markers analyzed, including E-cadherin, cytokeratin 8, and zonula occludens (ZO)-1alpha+. Furthermore, vimentin was expressed by GCs, suggesting a more mesenchymal phenotype. Under calcium-free conditions, small follicles maintained oocyte-GC contact, confirming the importance of calcium-independent nectin at this stage. However, in primary and multilayered follicles, lack of calcium resulted in loss of contact between GCs and oocyte, showing that nectin alone cannot maintain attachment between these two cell types. Lack of classic markers suggests that GCs are not epithelial. Identification of AJs during GC cuboidalization highlights the importance of AJs in regulating initiation of follicle growth.

  20. Presenilin 1/gamma-secretase is associated with cadmium-induced E-cadherin cleavage and COX-2 gene expression in T47D breast cancer cells.

    Science.gov (United States)

    Park, Chang Seok; Kim, Ohn Soon; Yun, Sang-Moon; Jo, Sangmee A; Jo, Inho; Koh, Young Ho

    2008-12-01

    Cadmium is a heavy metal that has multiple toxic effects on human health and has been classified as a human carcinogen. E-cadherin is a major target of cadmium; however, the roles of E-cadherin and cadmium and the mechanisms of tumor progression remain to be defined. Here, we demonstrate that cadmium increases E-cadherin processing via a gamma-secretase in the T47D breast cancer cell lines. This presenilin 1 (PS1)/gamma-secretase-dependent cleavage of E-cadherin was accompanied by changes in reactive oxygen species or calcium. E-cadherin cleavage was blocked by a PS1 dominant-negative mutant, gamma-secretase inhibitors [N-[N-(3,5-Difluorophenacetyl-L-alanyl)]-S-phenylglycine t-butyl ester (DAPT) and L-685,486], antioxidants (N-acetylcysteine and Mn(III)tetrakis(1-methyl-4-pyridyl)porphyrin pentachloride), or a calcium chelating drug 1,2-bis(o-Aminophenoxy)ethane-N,N,N',N'-tetraacetic acid tetra(acetoxymethyl) ester. Immunofluorescence analysis confirmed the disappearance of E-cadherin staining at the cell surface. Those inhibitors attenuated cadmium-induced cytotoxicity. Additionally, cadmium treatment increased cell motility and invasion ability, which was abated by DAPT. Interestingly, cyclooxygenase-2 (COX-2) expression induced by cadmium was also inhibited by DAPT. The cadmium-induced cell motility and invasion ability were inhibited by a COX-2 inhibitor, NS398. Our data indicate a novel molecular mechanism that links cytotoxicity of cadmium and disrupted E-cadherin processing to adherens junctions; cadmium induces COX-2 expression via gamma-secretase, which increases cell motility and invasion ability. Understanding the downstream signaling cascades of cadmium that promote tumor progression might be a key to the development of novel therapeutic strategies.

  1. An instructive role for C. elegans E-cadherin in translating cell contact cues into cortical polarity.

    Science.gov (United States)

    Klompstra, Diana; Anderson, Dorian C; Yeh, Justin Y; Zilberman, Yuliya; Nance, Jeremy

    2015-06-01

    Cell contacts provide spatial cues that polarize early embryos and epithelial cells. The homophilic adhesion protein E-cadherin is required for contact-induced polarity in many cells. However, it is debated whether E-cadherin functions instructively as a spatial cue, or permissively by ensuring adequate adhesion so that cells can sense other contact signals. In Caenorhabditis elegans, contacts polarize early embryonic cells by recruiting the RhoGAP PAC-1 to the adjacent cortex, inducing PAR protein asymmetry. Here we show that the E-cadherin HMR-1, which is dispensable for adhesion, functions together with the α-catenin HMP-1, the p120 catenin JAC-1, and the previously uncharacterized linker PICC-1 (human CCDC85A-C) to bind PAC-1 and recruit it to contacts. Mislocalizing the HMR-1 intracellular domain to contact-free surfaces draws PAC-1 to these sites and depolarizes cells, demonstrating an instructive role for HMR-1 in polarization. Our findings identify an E-cadherin-mediated pathway that translates cell contacts into cortical polarity by directly recruiting a symmetry-breaking factor to the adjacent cortex.

  2. E-cadherin interactions are required for Langerhans cell differentiation

    OpenAIRE

    Mayumi, Nobuko; Watanabe, Eri; Norose, Yoshihiko; Watari, Eiji; Kawana, Seiji; Geijtenbeek, Teunis B H; Takahashi, Hidemi

    2012-01-01

    Human skin contains the following two distinct DC subsets: (i) Langerhans cells (LCs), expressing Langerin but not DC-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN), are predominantly localized in the epidermis; and (ii) dermal DCs, expressing DC-SIGN but not Langerin, are observed mainly in the dermis. It is not known whether localization in the epidermis provides cues for LC differentiation. Here, we show that E-cadherin expressed by epidermal keratinocytes (KCs) ...

  3. Defining functional interactions during biogenesis of epithelial junctions

    Science.gov (United States)

    Erasmus, J. C.; Bruche, S.; Pizarro, L.; Maimari, N.; Pogglioli, T.; Tomlinson, C.; Lees, J.; Zalivina, I.; Wheeler, A.; Alberts, A.; Russo, A.; Braga, V. M. M.

    2016-01-01

    In spite of extensive recent progress, a comprehensive understanding of how actin cytoskeleton remodelling supports stable junctions remains to be established. Here we design a platform that integrates actin functions with optimized phenotypic clustering and identify new cytoskeletal proteins, their functional hierarchy and pathways that modulate E-cadherin adhesion. Depletion of EEF1A, an actin bundling protein, increases E-cadherin levels at junctions without a corresponding reinforcement of cell–cell contacts. This unexpected result reflects a more dynamic and mobile junctional actin in EEF1A-depleted cells. A partner for EEF1A in cadherin contact maintenance is the formin DIAPH2, which interacts with EEF1A. In contrast, depletion of either the endocytic regulator TRIP10 or the Rho GTPase activator VAV2 reduces E-cadherin levels at junctions. TRIP10 binds to and requires VAV2 function for its junctional localization. Overall, we present new conceptual insights on junction stabilization, which integrate known and novel pathways with impact for epithelial morphogenesis, homeostasis and diseases. PMID:27922008

  4. Characterization of cytoskeletal and junctional proteins expressed by cells cultured from human arachnoid granulation tissue

    Directory of Open Access Journals (Sweden)

    Mehta Bhavya C

    2005-10-01

    Full Text Available Abstract Background The arachnoid granulations (AGs are projections of the arachnoid membrane into the dural venous sinuses. They function, along with the extracranial lymphatics, to circulate the cerebrospinal fluid (CSF to the systemic venous circulation. Disruption of normal CSF dynamics may result in increased intracranial pressures causing many problems including headaches and visual loss, as in idiopathic intracranial hypertension and hydrocephalus. To study the role of AGs in CSF egress, we have grown cells from human AG tissue in vitro and have characterized their expression of those cytoskeletal and junctional proteins that may function in the regulation of CSF outflow. Methods Human AG tissue was obtained at autopsy, and explanted to cell culture dishes coated with fibronectin. Typically, cells migrated from the explanted tissue after 7–10 days in vitro. Second or third passage cells were seeded onto fibronectin-coated coverslips at confluent densities and grown to confluency for 7–10 days. Arachnoidal cells were tested using immunocytochemical methods for the expression of several common cytoskeletal and junctional proteins. Second and third passage cultures were also labeled with the common endothelial markers CD-31 or VE-cadherin (CD144 and their expression was quantified using flow cytometry analysis. Results Confluent cultures of arachnoidal cells expressed the intermediate filament protein vimentin. Cytokeratin intermediate filaments were expressed variably in a subpopulation of cells. The cultures also expressed the junctional proteins connexin43, desmoplakin 1 and 2, E-cadherin, and zonula occludens-1. Flow cytometry analysis indicated that second and third passage cultures failed to express the endothelial cell markers CD31 or VE-cadherin in significant quantities, thereby showing that these cultures did not consist of endothelial cells from the venous sinus wall. Conclusion To our knowledge, this is the first report of

  5. Aberrant Methylation of the E-Cadherin Gene Promoter Region in the Endometrium of Women With Uterine Fibroids.

    Science.gov (United States)

    Li, Yan; Ran, Ran; Guan, Yingxia; Zhu, Xiaoxiong; Kang, Shan

    2016-08-01

    A uterine fibroid is a leiomyoma that originates from the smooth muscle layer of the uterus. A variety of endometrial abnormalities are associated with uterine fibroids. This study aims to investigate the methylation status of the E-cadherin gene (CDH1) promoter region in the endometrium of patients with uterine fibroids. The methylation of CDH1 was studied using methylation-specific polymerase chain reaction in the endometrial tissue of 102 patients with uterine fibroids and 50 control patients. The E-cadherin expression was examined by flow cytometry. The methylation rate of CDH1 promoter region was 33.3% in the endometrium of patients with uterine fibroids and 8% in the endometrium of women without fibroids. The frequency of CDH1 promoter methylation in the endometrium of patients with fibroids was significantly higher than that in the endometrium of women without fibroids (P = .001). Furthermore, the E-cadherin expression level in methylation-positive tissues was significantly lower than that in methylation-negative tissues (P = .017). These results suggest that epigenetic aberration of CDH1 may occur in the endometrium of patients with fibroids, which may be associated with E-cadherin protein expression in endometrial tissue.

  6. Effects of Cigarette Smoke Extract on E-cadherin Expression in Cultured Airway Epithelial Cells

    Institute of Scientific and Technical Information of China (English)

    WANG Xi; WU Renling; CHEN Fang; HAO Tianling

    2000-01-01

    To investigate whether the change of E-cadherin (ECD) expression plays a role in the injury and repair of airway epithelial cells (AEC) caused by smoking, porcine AECs were cultured by using an enzyme-dispersed method. After exposure of the AECs to cigarette smoke extract(CSE), the ECD expression in the cells was detected by using immunocytochemistry and in situ hybridization. The results showed that ECD was distributed on the plasma membrane at the cell junctions of AECs. After exposure to 20% CSE, the membranous ECD expression was decreased, the cytoplasmic ECD expression was increased (P<0.01) as the exposure time went on.But the content of ECD mRNA in the AECs did not chang. It suggests that the change of ECD expression is regulated at the posttranslational level and plays a role in the injury and repair of AEC caused by smoking.

  7. Relationship between E-cadherin and diabetic nephropathy

    Institute of Scientific and Technical Information of China (English)

    姜洪娟

    2014-01-01

    Objective To identify novel biomarker for diabetic nephropathy(DN)by urinary proteomic methods,and to detect the expression of E-cadherin in urine and renal tissue of patients with DN.Methods Urine samples were collected from 12 cases of type 1 diabetic nephropathy patients(T1DN),12 cases of type 2 diabetic nephropathy patients(T2DN),12 cases of nephritic syndrome patients(NS),and 12 cases of healthy Controls.Comparative proteomic approach of two-dimensional gel electro-

  8. Evidence for a role of E-cadherin in suppressing liver carcinogenesis in mice and men.

    Science.gov (United States)

    Schneider, Marlon R; Hiltwein, Felix; Grill, Jessica; Blum, Helmut; Krebs, Stefan; Klanner, Andrea; Bauersachs, Stefan; Bruns, Christiane; Longerich, Thomas; Horst, David; Brandl, Lydia; de Toni, Enrico; Herbst, Andreas; Kolligs, Frank T

    2014-08-01

    The cell adhesion molecule E-cadherin has critical functions in development and carcinogenesis. Impaired expression of E-cadherin has been associated with disrupted tissue homeostasis, progression of cancer and a worse patient prognosis. So far, the role of E-cadherin in homeostasis and carcinogenesis of the liver is not well understood. By use of a mouse model with liver-specific deletion of E-cadherin and administration of the carcinogen diethylnitrosamine, we demonstrate that loss of E-cadherin expression in hepatocytes results in acceleration of the growth of hepatocellular carcinoma (HCC). In contrast, liver regeneration is not disturbed in mice lacking E-cadherin expression in hepatocytes. In human HCC, we observed four different expression patterns of E-cadherin. Notably, atypical cytosolic expression of E-cadherin was positively correlated with a poorer patient prognosis. The median overall survival of patients with HCC expressing E-cadherin on the membrane only was 221 weeks (95% confidence interval: 51-391) compared with 131 weeks in patients with cytosolic expression (95% confidence interval: 71-191 weeks; P < 0.05). In conclusion, we demonstrate that impaired expression of E-cadherin promotes hepatocellular carcinogenesis and is associated with a worse prognosis in humans.

  9. Expression of e-cadherin, n-cadherin and snail and their correlation with clinicopathological variants: an immunohistochemical study of 132 invasive ductal breast carcinomas in Egypt

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    Hanan Mohamed Abd ElMoneim

    2011-01-01

    Full Text Available OBJECTIVE: To evaluate the expression of the cell adhesion molecules E-cadherin and N-cadherin and the transcription factor Snail in invasive ductal breast carcinomas and to determine their relationships with clinicopathological features. METHODS: Immunohistochemistry was used to examine E-cadherin, N-cadherin, and Snail protein expression in 132 invasive breast carcinomas. RESULTS: The expression of E-cadherin was decreased (negative or weak in 37.1% of invasive carcinomas, while N-cadherin and Snail overexpression were detected in 51.9% and 40.9% of carcinomas, respectively. Low E-cadherin expression was significantly correlated with poorly differentiated carcinoma (53.1%, positive node status (80.9%, poor Nottingham Prognostic Index (64.7%, and the presence of estrogen and progesterone receptors. Overexpression of N-cadherin and Snail were also significantly correlated with poorly differentiated carcinoma, positive node status, and poor Nottingham Prognostic Index but were correlated with the absence of hormone receptors. Loss of E-cadherin immunoexpression was strongly associated with the presence of membranous N-cadherin (87.8% and nuclear Snail (69.4%. CONCLUSION: Loss of E-cadherin and overexpression of N-cadherin and Snail in breast carcinomas may play a central role in the development of invasive ductal breast carcinoma. These biomarkers may provide a valuable reference for the study of invasive ductal carcinoma progression and to characterize the biological behavior of the tumor. In the future, increased N-cadherin and decreased E-cadherin expression may be used as indicators of the progression and prognosis of invasive ductal carcinoma.

  10. Estudo da relação entre a imunoexpressão das proteínas caderina-E e DCC com o grau de diferenciação celular e o estadiamento TNM do adenocarcinoma colorretal Study of the expression of E-cadherin and DCC proteins with cell differentiation degree and staging in colorectal adenocarcinoma

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    Marcos Vinicius Araújo Denadai

    2007-10-01

    as to the expression of E-cadherin and delect in colon cancer (DCC proteins, being classified as positive whenever it was detected immunoexpression of such proteins in 50% or more tumor cells. RESULTS: For TNM, E-cadherin immunoexpression for stage I: positive in 72.7% and negative in 35.7%; stage IV: positive in 64.3% and negative in 35.7%. For DCC protein: 43.2% positive and 56.8% negative in stage I, and 50% positive and 50% negative in stage IV. Regarding the cell differentiation degree, the immunoexpression of E-cadherin - GI: positive in 70% and negative in 30%; GII: positive in 68.4% and negative in 31.6%; GIII: positive in 63.6% and negative in 36.4%. The immunoexpression of DCC - GI: 40% positive and 60% negative; GII: 46.8% positive and 53.2% negative; GIII: 54.5% positive and 45.5% negative. There was no significant difference among groups. CONCLUSION: The results of this research make it possible to come to the conclusion that there is no relationship between the immunoexpression of E-cadherin and DCC proteins with TNM staging (I and IV and cell differentiation degree in colorectal cancer.

  11. The Anoikis Effector Bit1 Inhibits EMT through Attenuation of TLE1-Mediated Repression of E-Cadherin in Lung Cancer Cells.

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    Yao, Xin; Pham, Tri; Temple, Brandi; Gray, Selena; Cannon, Cornita; Chen, Renwei; Abdel-Mageed, Asim B; Biliran, Hector

    The mitochondrial Bcl-2 inhibitor of transcription 1 (Bit1) protein is part of an anoikis-regulating pathway that is selectively dependent on integrins. We previously demonstrated that the caspase-independent apoptotic effector Bit1 exerts tumor suppressive function in lung cancer in part by inhibiting anoikis resistance and anchorage-independent growth in vitro and tumorigenicity in vivo. Herein we show a novel function of Bit1 as an inhibitor cell migration and epithelial-mesenchymal transition (EMT) in the human lung adenocarcinoma A549 cell line. Suppression of endogenous Bit1 expression via siRNA and shRNA strategies promoted mesenchymal phenotypes, including enhanced fibroblastoid morphology and cell migratory potential with concomitant downregulation of the epithelial marker E-cadherin expression. Conversely, ectopic Bit1 expression in A549 cells promoted epithelial transition characterized by cuboidal-like epithelial cell phenotype, reduced cell motility, and upregulated E-cadherin expression. Specific downregulation of E-cadherin in Bit1-transfected cells was sufficient to block Bit1-mediated inhibition of cell motility while forced expression of E-cadherin alone attenuated the enhanced migration of Bit1 knockdown cells, indicating that E-cadherin is a downstream target of Bit1 in regulating cell motility. Furthermore, quantitative real-time PCR and reporter analyses revealed that Bit1 upregulates E-cadherin expression at the transcriptional level through the transcriptional regulator Amino-terminal Enhancer of Split (AES) protein. Importantly, the Bit1/AES pathway induction of E-cadherin expression involves inhibition of the TLE1-mediated repression of E-cadherin, by decreasing TLE1 corepressor occupancy at the E-cadherin promoter as revealed by chromatin immunoprecipitation assays. Consistent with its EMT inhibitory function, exogenous Bit1 expression significantly suppressed the formation of lung metastases of A549 cells in an in vivo experimental

  12. The Anoikis Effector Bit1 Inhibits EMT through Attenuation of TLE1-Mediated Repression of E-Cadherin in Lung Cancer Cells

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    Yao, Xin; Pham, Tri; Temple, Brandi; Gray, Selena; Cannon, Cornita; Chen, Renwei; Abdel-Mageed, Asim B.; Biliran, Hector

    2016-01-01

    The mitochondrial Bcl-2 inhibitor of transcription 1 (Bit1) protein is part of an anoikis-regulating pathway that is selectively dependent on integrins. We previously demonstrated that the caspase-independent apoptotic effector Bit1 exerts tumor suppressive function in lung cancer in part by inhibiting anoikis resistance and anchorage-independent growth in vitro and tumorigenicity in vivo. Herein we show a novel function of Bit1 as an inhibitor cell migration and epithelial–mesenchymal transition (EMT) in the human lung adenocarcinoma A549 cell line. Suppression of endogenous Bit1 expression via siRNA and shRNA strategies promoted mesenchymal phenotypes, including enhanced fibroblastoid morphology and cell migratory potential with concomitant downregulation of the epithelial marker E-cadherin expression. Conversely, ectopic Bit1 expression in A549 cells promoted epithelial transition characterized by cuboidal-like epithelial cell phenotype, reduced cell motility, and upregulated E-cadherin expression. Specific downregulation of E-cadherin in Bit1-transfected cells was sufficient to block Bit1-mediated inhibition of cell motility while forced expression of E-cadherin alone attenuated the enhanced migration of Bit1 knockdown cells, indicating that E-cadherin is a downstream target of Bit1 in regulating cell motility. Furthermore, quantitative real-time PCR and reporter analyses revealed that Bit1 upregulates E-cadherin expression at the transcriptional level through the transcriptional regulator Amino-terminal Enhancer of Split (AES) protein. Importantly, the Bit1/AES pathway induction of E-cadherin expression involves inhibition of the TLE1-mediated repression of E-cadherin, by decreasing TLE1 corepressor occupancy at the E-cadherin promoter as revealed by chromatin immunoprecipitation assays. Consistent with its EMT inhibitory function, exogenous Bit1 expression significantly suppressed the formation of lung metastases of A549 cells in an in vivo experimental

  13. E-cadherin expression and its clinical significance in 41 cases of spinal plasma cell myeloma

    Institute of Scientific and Technical Information of China (English)

    Wang Liangzhe; Liu Huimin; He Jin; Li Yuli; Xu Yi; Chen Bing

    2009-01-01

    Objective: To investigate the expression level of E-cadherin in spinal plasma cell myeloma and its relationship with the clinicopathological indexes of spinal plasma cell myeloma. Methods: The expression of E-cadherin was detected in 41 cases of spinal plasma cell myeloma and 14 cases of simple bone cysts by using S-P (streptavidin-perosidase) immunohistochemical staining. The relationship between E-cadherin expression and the clinicopathological features was analyzed. Results: In spinal plasma cell myelomas, the positive expression rate of E-cadherin (46.34 %) was higher than that in simple bone cyst tissues (all negative) (P0.05), but had relationship with the classification of light chain. The expression rate in lambda chain subgroup was lower than that in the others (P<0.05). We also found the E-cadherin negative patients had a higher overall survival rate than those who had strong E-cadherin expression (P<0.05). Conclusion: E-cadherin expressed higher in spinal plasma cell myelomas than in simple bone cyst tissues and its expression had relationship with the light chain classification in spinal plasma cell myeloma. The patients with no stain of E-cadherin may have a poor prognosis. Detecting the type of light chain associated with expression of E-cadherin might be helpful in evaluating the outcome of spinal PCM patients.

  14. Reduced E-cadherin facilitates renal cell carcinoma progression by WNT/β-catenin signaling activation.

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    Zhang, Xinqi; Yang, Mingxi; Shi, Hua; Hu, Jianxin; Wang, Yuanlin; Sun, Zhaolin; Xu, Shuxiong

    2017-02-15

    Reduced expression of E-cadherin was observed in renal cell carcinoma (RCC). However, its potential clinical value and correlation with WNT/β-catenin signaling in RCC progression was still unclear. Immunohistochemical staining was performed in RCC tissue microarray to examine the expression status and prognosis value of E-cadherin and β-catenin. The potential role of E-cadherin in β-catenin translocation was analyzed with immunobloting assays. A significant negative correlation was observed between E-cadherin and β-catenin expression in RCC tissues. E-cadherin inhibits β-catenin translocation from membrane to cytoplasm in RCC tissues, which was an important step for WNT/β-catenin signaling. Reduced E-cadherin expression was associated with poor prognosis. More importantly, E-cadherin-/β-catenin+ was an independent detrimental factor for survival estimation of RCC patients. Reduced E-cadherin expression in RCC promoted cancer progression via WNT/β-catenin signaling pathway activation. E-cadherin/β-catenin provides a valuable prognosis marker for RCC, which may be an effective target for RCC therapy.

  15. Prognostic and clinicopathological features of E-cadherin, α-catenin, β-catenin, γ-catenin and D1 cyclin expression in human esophageal squamous cell carcinoma

    Institute of Scientific and Technical Information of China (English)

    Ying-Cheng Lin; Ming-Yao Wu; De-Rui Li; Xian-Ying Wu; Rui-Ming Zheng

    2004-01-01

    AIM: To investigate the expression of E-cadherin, α-catenin,β-catenin, γ-catenin and cyclin D1 in patients with esophageal squamous cell carcinoma (ESCC), and analyze their interrelationship with clinicopathological variables and their effects on prognosis.METHODS: Expression of E-cadherin, α-catenin, β-catenin,γ-catenin and cyclin D1 was determined by EnVision or SABC immunohistochemical technique in patients with ESCC consecutively, their correlation with clinical characteristics was evaluated and analyzed by univariate analysis.RESULTS: The reduced expression rate of E-cadherin, α-catenin, β-catenin and γ-catenin was 88.7%, 69.4%, 35.5%and 53.2%, respectively. Cyclin D1 positive expression rate was 56.5%. Expression of γ-catenin was inversely correlated with the degree of tumor differentiation and lymph node metastasis (x2 = 4.183 and x2 = 5.035, respectively, P<0.05),whereas the expression of E-cadherin was correlated only with the degree of differentiation (x2 = 5.769, P<0.05).Reduced expression of E-cadherin and γ-catenin was associated with poor differentiation of tumor, reduced expression of γ-catenin was also associated with lymph node metastasis. There obviously existed an inverse correlation between level of E-cadherin and γ-catenin protein and survival. The 3-year survival rates were 100% and56% in E-cadherin preserved expression group and in reduced expression one and were 78% and 48% in γ-catenin preserved expression group and in reduced expression one,respectively. The differences were both statistically significant. Correlation analysis showed the expression level of α-catenin correlated with that of E-cadherin and β-catenin(P<0.05).CONCLUSION: The reduced expression of E-cadherin and γ-catenin, but not α-catenin, β-catenin and cydin D1, implies more aggressive malignant behaviors of esophageal carcinoma cells and predicts the poor prognosis of patients.

  16. Impact of p120-catenin isoforms 1A and 3A on epithelial mesenchymal transition of lung cancer cells expressing E-cadherin in different subcellular locations.

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    Yijun Zhang

    Full Text Available The epithelial mesenchymal transition (EMT is an important process in tumor development. Despite previous investigations, it remains unclear how p120-catenin (p120ctn isoforms 1A and 3A affect the EMT of tumor cells. Here we investigated expression of p120ctn, E-cadherin and vimentin in 78 human non-small cell lung cancer (NSCLC samples by immunohistochemistry and found that p120ctn membrane expression positively correlated with E-cadherin expression (P<0.001 and negatively correlated with vimentin expression and lymph node metastasis (P<0.05. Meanwhile, p120ctn cytoplasmic expression negatively correlated with E-cadherin expression (P<0.001 and positively correlated with vimentin expression and lymph node metastasis (P<0.05. Cells expressing high (H460 and SPC and low (H1299 and LK2 levels of p120ctn were screen to investigate its impact on EMT. E-cadherin was restricted to the cell membrane in H460 and H1299 cells, whereas it was expressed in the cytoplasm of SPC and LK2 cells. Ablation of endogenous p120ctn isoform 1A in cells expressing high levels of the protein resulted in decreased E-cadherin expression, increased N-cadherin, vimentin and snail expression and enhanced invasiveness in H460 cells. Meanwhile, completely opposite results were observed in SPC cells. Furthermore, transfection of in H1299 cells expressing low p120ctn levels with the p120ctn isoform 1A plasmid resulted in increased E-cadherin expression, decreased N-cadherin, vimentin and snail expression and weakened invasiveness, while LK2 cells showed completely opposite results. Both cell lines expressing low p120ctn levels and transfected with the p120ctn isoform 3A plasmid appeared to have increased E-cadherin expression, decreased N-cadherin, vimentin and snail expression and weakened invasiveness. In conclusion, in cells with membrane E-cadherin, both p120ctn isoforms 1A and 3A inhibited EMT and decreased cell invasiveness. In cells with cytoplasmic E-cadherin, p120ctn

  17. Analysis of Snail-1, E-Cadherin and Claudin-1 Expression in Colorectal Adenomas and Carcinomas

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    Kamil Belej

    2012-02-01

    Full Text Available We report the expression of Snail-1, E-cadherin and claudin-1 by indirect immunohistochemistry in colonic neoplasia. Snail-1 is a zinc finger transcription factor expressed in cells that already have undergone almost complete epithelial-mesenchymal transition (EMT and have already evaded from the tumor. The main mechanism by which Snail induces EMT is downregulation of E-cadherin, of which expression was shown to be frequently downregulated in many different types of tumors, where it accompanies the invasiveness and metastatic behavior of malignant cells. Moreover, Snail-1 may downregulate the expression of claudin-1, a cell-cell adhesion protein which plays a likely role in progression and dissemination during tumorigenesis. Snail-1 was expressed in both carcinoma and adenoma cells with histologically normal epithelium in the mucosa, adjacent to the tumors, without significant differences, and predominant strong intensity of staining. Statistically significant differences were revealed between normal and tumorous epithelium (p = 0.003 at the subcellular level, where the shift of the protein to the cytoplasm with combined cytoplasmic/nuclear or pure cytoplasmic expression was observed. E-cadherin expression was present in 100% of cases of both adenocarcinomas and adenomas, with prevailing strong membranous immunoreactivity and no differences between protein expression in tumors and normal mucosa. Predominating strong positivity of claudin-1 was detected in tumor cells of adenocarcinomas and adenomas. Marked differences were seen in protein localization, where membranous staining, typical for nontumorous epithelium, changed to combined membranous/cytoplasmic expression in adenocarcinomas (p = 0.0001 and adenomas (0.0002, in which cytoplasmic shift was associated with a higher degree of dysplasia. Furthermore, membranous/cytoplasmic localization was more frequent in the carcinoma group (87% in comparison with adenomas (51% (p = 0.0001. We conclude

  18. Inhibition of p300 histone acetyltransferase activity in palate mesenchyme cells attenuates Wnt signaling via aberrant E-cadherin expression.

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    Warner, Dennis R; Smith, Scott C; Smolenkova, Irina A; Pisano, M Michele; Greene, Robert M

    2016-03-01

    p300 is a multifunctional transcriptional coactivator that interacts with numerous transcription factors and exhibits protein/histone acetyltransferase activity. Loss of p300 function in humans and in mice leads to craniofacial defects. In this study, we demonstrated that inhibition of p300 histone acetyltransferase activity with the compound, C646, altered the expression of several genes, including Cdh1 (E-cadherin) in mouse maxillary mesenchyme cells, which are the cells that give rise to the secondary palate. The increased expression of plasma membrane-bound E-cadherin was associated with reduced cytosolic β-catenin, that led to attenuated signaling through the canonical Wnt pathway. Furthermore, C646 reduced both cell proliferation and the migratory ability of these cells. These results suggest that p300 histone acetyltransferase activity is critical for Wnt-dependent palate mesenchymal cell proliferation and migration, both processes that play a significant role in morphogenesis of the palate.

  19. Alterations in junctional proteins, inflammatory mediators and extracellular matrix molecules in eosinophilic esophagitis.

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    Abdulnour-Nakhoul, Solange M; Al-Tawil, Youhanna; Gyftopoulos, Alex A; Brown, Karen L; Hansen, Molly; Butcher, Kathy F; Eidelwein, Alexandra P; Noel, Robert A; Rabon, Edd; Posta, Allison; Nakhoul, Nazih L

    2013-08-01

    Eosinophilic esophagitis (EoE), an inflammatory atopic disease of the esophagus, causes massive eosinophil infiltration, basal cell hyperplasia, and sub-epithelial fibrosis. To elucidate cellular and molecular factors involved in esophageal tissue damage and remodeling, we examined pinch biopsies from EoE and normal pediatric patients. An inflammation gene array confirmed that eotaxin-3, its receptor CCR3 and interleukins IL-13 and IL-5 were upregulated. An extracellular matrix (ECM) gene array revealed upregulation of CD44 & CD54, and of ECM proteases (ADAMTS1 & MMP14). A cytokine antibody array showed a marked decrease in IL-1α and IL-1 receptor antagonist and an increase in eotaxin-2 and epidermal growth factor. Western analysis indicated reduced expression of intercellular junction proteins, E-cadherin and claudin-1 and increased expression of occludin and vimentin. We have identified a number of novel genes and proteins whose expression is altered in EoE. These findings provide new insights into the molecular mechanisms of the disease.

  20. Cleavage of E-Cadherin by Matrix Metalloproteinase-7 Promotes Cellular Proliferation in Nontransformed Cell Lines via Activation of RhoA

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    Conor C. Lynch

    2010-01-01

    Full Text Available Perturbations in cell-cell contact machinery occur frequently in epithelial cancers and result in increased cancer cell migration and invasion. Previously, we demonstrated that MMP-7, a protease implicated in mammary and intestinal tumor growth, can process the adherens junction component E-cadherin. This observation leads us to test whether MMP-7 processing of E-cadherin could directly impact cell proliferation in nontransformed epithelial cell lines (MDCK and C57MG. Our goal was to investigate the possibility that MMP-7 produced by cancer cells may have effects on adjacent normal epithelium. Here, we show that MMP-7 processing of E-cadherin mediates, (1 loss of cell-cell contact, (2 increased cell migration, (3 a loss of epithelial cell polarization and (4 increased cell proliferation via RhoA activation. These data demonstrate that MMP-7 promotes epithelial cell proliferation via the processing of E-cadherin and provide insights into the molecular mechanisms that govern epithelial cell growth.

  1. E-cadherin expression in obesity-associated, Kras-initiated pancreatic ductal adenocarcinoma in mice.

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    Stark, Alexander P; Chang, Hui-Hua; Jung, Xiaoman; Moro, Aune; Hertzer, Kathleen; Xu, Mu; Schmidt, Andrea; Hines, O Joe; Eibl, Guido

    2015-12-01

    The epithelial-mesenchymal transition (EMT) is critical in the development of invasive epithelial malignancies. EMT is accelerated by inflammation and results in decreased E-cadherin expression. Diet-induced obesity is an inflammatory state that accelerates pancreatic carcinogenesis; its effect on EMT and E-cadherin expression in the development of pancreatic ductal adenocarcinoma is unclear. Conditional Kras(G12D) mice were fed a control diet or a high-fat, high-calorie diet for 3 or 9 months (n = 10 each). Immunohistochemistry with anti-E-cadherin antibody was performed. E-cadherin expression was characterized by staining intensity, location, and proportion of positive cells. In vitro expression of E-cadherin and Slug in primary pancreatic intraepithelial neoplasia (PanIN) and cancer cells was determined by Western blot. The HFCD led to increased weight gain in both 3- (15.8 vs 5.6 g, P cancer, E-cadherin expression was aberrant, with loss of membranous staining and prominent cytoplasmic staining, associated with strong, cytoplasmic expression of β-catenin. In vitro expression of E-cadherin was greatest in primary PanIN cells, accompanied by absent Slug expression. Cancer cell lines demonstrated significantly decreased E-cadherin expression in the presence of upregulated Slug. Despite increased pancreatic inflammation and accelerated carcinogenesis, the high-fat, high-calorie diet did not induce changes in E-cadherin expression in PanIN lesions of all stages. Invasive lesions demonstrated aberrant cytoplasmic E-cadherin staining. Loss of normal membranous localization may reflect a functional loss of E-cadherin. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Cell culture model predicts human disease: Altered expression of junction proteins and matrix metalloproteinases in cervical dysplasia

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    Kivi Niina

    2012-08-01

    Full Text Available Abstract Background Cervical cancer is necessarily caused by human papillomaviruses, which encode three oncogenes manifesting their functions by interfering with a number of cellular proteins and pathways: the E5, E6, and E7 proteins. We have earlier found in our microarray studies that the E5 oncogene crucially affects the expression of cellular genes involved in adhesion and motility of epithelial cells. Methods In order to biologically validate our previous experimental findings we performed immunohistochemical staining of a representative set of tissue samples from different grades of high-risk human papillomavirus associated cervical disease as well as normal squamous and columnar cervical epithelium. Three-dimensional collagen raft cultures established from E5-expressing and control epithelial cells were also examined. The expression of p16, matrix metalloproteinase (MMP -7, MMP-16, cytokeratin (CK 8/18, laminin, E-cadherin and beta-catenin was studied. Results In agreement with our previous microarray studies, we found intense staining for E-cadherin and beta-catenin in adherens junctions even in high-grade cervical lesions. Staining for MMP-16 was increased in severe disease as well. No significant change in staining for MMP-7 and cytokeratin 8/18 along with the grade of cervical squamous epithelial disease was observed. Conclusions Here we have confirmed, using tissue material from human papillomavirus associated lesions, some of the cellular gene expression modifications that we earlier reported in an experimental system studying specifically the E5 oncogene of papillomaviruses. These findings were partially surprising in the context of cervical carcinogenesis and emphasize that the complexity of carcinogenesis is not yet fully understood. Microarray approaches provide a wide overwiev of gene expression in experimental settings, which may yield biologically valid biomarkers for disease diagnostics, prognosis, and follow-up.

  3. Meta-analysis of downregulated E-cadherin as a poor prognostic biomarker for cervical cancer.

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    Peng, Jifeng; Qi, Shengnan; Wang, Ping; Li, Wanyu; Song, Lingxie; Liu, Chunxia; Li, Feng

    2016-03-01

    This meta-analysis was conducted to evaluate the diagnostic and prognostic functions of E-cadherin expression in cervical cancer. PubMed and other databases were searched for articles associated with E-cadherin and cervical cancer. These articles were published before June 2015 and written in English or Chinese. Random-effects model was used to pool odds ratios on the heterogeneity test in the meta-analysis. All of 20 studies were analyzed, in which 522 (42.6%) subjects exhibited reduced E-cadherin expression. Evaluation of clinicopathologic features showed that the downregulation of E-cadherin was related to the overall survival, clinicopathological parameters and age. Downregulation of E-cadherin in cervical cancer patients showed poor overall survival. Therefore, E-cadherinmay be a metastasis-suppressor gene in cervical cancer.

  4. Alpha-catenin-Dependent Recruitment of the Centrosomal Protein CAP350 to Adherens Junctions Allows Epithelial Cells to Acquire a Columnar Shape

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    Zurbano, Angel; Formstecher, Etienne; Martinez-Morales, Juan R.; Bornens, Michel; Rios, Rosa M.

    2015-01-01

    Epithelial morphogenesis involves a dramatic reorganisation of the microtubule cytoskeleton. How this complex process is controlled at the molecular level is still largely unknown. Here, we report that the centrosomal microtubule (MT)-binding protein CAP350 localises at adherens junctions in epithelial cells. By two-hybrid screening, we identified a direct interaction of CAP350 with the adhesion protein α-catenin that was further confirmed by co-immunoprecipitation experiments. Block of epithelial cadherin (E-cadherin)-mediated cell-cell adhesion or α-catenin depletion prevented CAP350 localisation at cell-cell junctions. Knocking down junction-located CAP350 inhibited the establishment of an apico-basal array of microtubules and impaired the acquisition of columnar shape in Madin-Darby canine kidney II (MDCKII) cells grown as polarised epithelia. Furthermore, MDCKII cystogenesis was also defective in junctional CAP350-depleted cells. CAP350-depleted MDCKII cysts were smaller and contained either multiple lumens or no lumen. Membrane polarity was not affected, but cortical microtubule bundles did not properly form. Our results indicate that CAP350 may act as an adaptor between adherens junctions and microtubules, thus regulating epithelial differentiation and contributing to the definition of cell architecture. We also uncover a central role of α-catenin in global cytoskeleton remodelling, in which it acts not only on actin but also on MT reorganisation during epithelial morphogenesis. PMID:25764135

  5. Phosphatidylinositol 5-phosphate 4-kinase type II beta is required for vitamin D receptor-dependent E-cadherin expression in SW480 cells

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    Kouchi, Zen, E-mail: zkouchi@toyaku.ac.jp [Laboratory of Genome and Biosignals, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji-city, Tokyo 192-0392 (Japan); Fujiwara, Yuki [Laboratory of Genome and Biosignals, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji-city, Tokyo 192-0392 (Japan); Yamaguchi, Hideki [Division of Metastasis and Invasion Signaling, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045 (Japan); PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi-city, Saitama 332-0012 (Japan); Nakamura, Yoshikazu; Fukami, Kiyoko [Laboratory of Genome and Biosignals, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji-city, Tokyo 192-0392 (Japan)

    2011-05-20

    Highlights: {yields} We analyzed Phosphatidylinositol 5-phosphate kinase II{beta} (PIPKII{beta}) function in cancer. {yields} PIPKII{beta} is required for vitamin D receptor-mediated E-cadherin upregulation in SW480. {yields} PIPKII{beta} suppresses cellular motility through E-cadherin induction in SW480 cells. {yields} Nuclear PIP{sub 2} but not plasma membrane-localized PIP{sub 2} mediates E-cadherin upregulation. -- Abstract: Numerous epidemiological data indicate that vitamin D receptor (VDR) signaling induced by its ligand or active metabolite 1{alpha},25-dihydroxyvitamin D{sub 3} (1{alpha},25(OH){sub 2}D{sub 3}) has anti-cancer activity in several colon cancers. 1{alpha},25(OH){sub 2}D{sub 3} induces the epithelial differentiation of SW480 colon cancer cells expressing VDR (SW480-ADH) by upregulating E-cadherin expression; however, its precise mechanism remains unknown. We found that phosphatidylinositol-5-phosphate 4-kinase type II beta (PIPKII{beta}) but not PIPKII{alpha} is required for VDR-mediated E-cadherin induction in SW480-ADH cells. The syntenin-2 postsynaptic density protein/disc large/zona occludens (PDZ) domain and pleckstrin homology domain of phospholipase C-delta1 (PLC{delta}1 PHD) possess high affinity for phosphatidylinositol-4,5-bisphosphate (PI(4,5)P{sub 2}) mainly localized to the nucleus and plasma membrane, respectively. The expression of syntenin-2 PDZ but not PLC{delta}1 PHD inhibited 1{alpha},25(OH){sub 2}D{sub 3}-induced E-cadherin upregulation, suggesting that nuclear PI(4,5)P{sub 2} production mediates E-cadherin expression through PIPKII{beta} in a VDR-dependent manner. PIPKII{beta} is also involved in the suppression of the cell motility induced by 1{alpha},25(OH){sub 2}D{sub 3}. These results indicate that PIPKII{beta}-mediated PI(4,5)P{sub 2} signaling is important for E-cadherin upregulation and inhibition of cellular motility induced by VDR activation.

  6. P120ctn overexpression enhances β-catenin-E-cadherin binding and down regulates expression of survivin and cyclin D1 in BEL-7404 hepatoma cells

    Institute of Scientific and Technical Information of China (English)

    Chao-Zan Nong; Li-Li Pan; Wei-Sheng He; Xi-Liang Zha; Hai-Hong Ye; Hua-Yi Huang

    2006-01-01

    AIM: To understand the role of P120ctn in E-cadherin-mediated cell-cell adhesion and signaling as well as in hepatoma cell biological function.METHODS: We stably overexpressed p120ctn isoform 3A in BEL-7404 human hepatoma cells and studied the effect of p120ctn on β-catenin and E-cadherin binding as well as p120ctn and β-catenin subcellular localization using immunoprecipitation, Western blotting and confocalmicroscopy. We also investigated the inhibitory effect of p120ctn transfection on the expression of apoptotic protein survivin survivin and cell cycle regulator cyclin D1in the cells.RERULTS: Western blotting indicated that p120ctn expression increased after cells were transfected with p120ctn isoform 3A. The protein was located mainly at membrane under immunofluorescent microscope.β-catenin nuclear expression was reduced after overexpression of p120ctn isoform 3A. The p120ctn-E-cadherin binding increased after transfection of p120ctn isoform 3A. Furthermore, overexpression of p120ctn down regulated the expression of apoptotic protein survivin and cell cycle regulator cyclin D1. These effects led to reduction of cell proliferation.CONCLUSION: Our results indicate that p120ctn plays an important role in regulating the formation of E-cadherin and -catenin complex, cell apoptosis, cell cycle and cancer cell biological function.

  7. E-cadherin destabilization accounts for the pathogenicity of missense mutations in hereditary diffuse gastric cancer.

    Directory of Open Access Journals (Sweden)

    Joana Simões-Correia

    Full Text Available E-cadherin is critical for the maintenance of tissue architecture due to its role in cell-cell adhesion. E-cadherin mutations are the genetic cause of Hereditary Diffuse Gastric Cancer (HDGC and missense mutations represent a clinical burden, due to the uncertainty of their pathogenic role. In vitro and in vivo, most mutations lead to loss-of-function, although the causal factor is unknown for the majority. We hypothesized that destabilization could account for the pathogenicity of E-cadherin missense mutations in HDGC, and tested our hypothesis using in silico and in vitro tools. FoldX algorithm was used to calculate the impact of each mutation in E-cadherin native-state stability, and the analysis was complemented with evolutionary conservation, by SIFT. Interestingly, HDGC patients harbouring germline E-cadherin destabilizing mutants present a younger age at diagnosis or death, suggesting that the loss of native-state stability of E-cadherin accounts for the disease phenotype. To elucidate the biological relevance of E-cadherin destabilization in HDGC, we investigated a group of newly identified HDGC-associated mutations (E185V, S232C and L583R, of which L583R is predicted to be destabilizing. We show that this mutation is not functional in vitro, exhibits shorter half-life and is unable to mature, due to premature proteasome-dependent degradation, a phenotype reverted by stabilization with the artificial mutation L583I (structurally tolerated. Herein we report E-cadherin structural models suitable to predict the impact of the majority of cancer-associated missense mutations and we show that E-cadherin destabilization leads to loss-of-function in vitro and increased pathogenicity in vivo.

  8. Mucinous Colorectal Adenocarcinoma: Influence of EGFR and E-Cadherin Expression on Clinicopathologic Features and Prognosis.

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    Foda, Abd AlRahman M; AbdelAziz, Azza; El-Hawary, Amira K; Hosni, Ali; Zalata, Khalid R; Gado, Asmaa I

    2015-08-01

    Previous studies have shown conflicting results on epidermal growth factor receptor (EGFR) and E-cadherin expression in colorectal carcinoma and their prognostic significance. To the best of our knowledge, this study is the first to investigate EGFR and E-cadherin expression, interrelation and relation to clinicopathologic, histologic parameters, and survival in rare colorectal mucinous adenocarcinoma (MA). In this study, we studied tumor tissue specimens from 150 patients with colorectal MA and nonmucinous adenocarcinoma (NMA). High-density manual tissue microarrays were constructed using modified mechanical pencil tips technique, and immunohistochemistry for EGFR and E-cadherin was performed. All relations were analyzed using established statistical methodologies. NMA expressed EGFR and E-cadherin in significantly higher rates with significant heterogenous pattern than MA. EGFR and E-cadherin positivity rates were significantly interrelated in both NMA and MA groups. In the NMA group, high EGFR expression was associated with old age, male sex, multiplicity of tumors, lack of mucinous component, and association with schistosomiasis. However, in the MA group, high EGFR expression was associated only with old age and MA subtype rather than signet ring carcinoma subtype. Conversely, high E-cadherin expression in MA cases was associated with old age, fungating tumor configuration, MA subtype, and negative intratumoral lymphocytic response. However, in the NMA cases, none of these factors was statistically significant. In a univariate analysis, neither EGFR nor E-cadherin expression showed a significant impact on disease-free or overall survival. Targeted therapy against EGFR and E-cadherin may not be useful in patients with MA. Neither EGFR nor E-cadherin is an independent prognostic factor in NMA or MA.

  9. Podoplanin, E-cadherin, β-catenin, and CD44v6 in recurrent ameloblastoma: their distribution patterns and relevance.

    Science.gov (United States)

    Siar, Chong Huat; Ishak, Ismadi; Ng, Kok Han

    2015-01-01

    Ameloblastoma is a benign but locally infiltrative odontogenic epithelial neoplasm with a high risk for recurrence. Podoplanin, a lymphatic endothelium marker, putatively promotes collective cell migration and invasiveness in this neoplasm. However, its role in the recurrent ameloblastoma (RA) remains unclear. As morphological, signaling, and genetic differences may exist between primary and recurrent tumors, clarification of their distribution patterns is of relevance. Podoplanin was examined immunohistochemically in conjunction with E-cadherin, β-catenin, and CD44v6 in 25 RA. Immunostaining according to tumor area, cellular type, and location, and relationship of these proteins were analyzed. Findings were compared with 25 unrelated primary ameloblastomas (UPA). All four proteins were detected in RA and UPA samples. Expression rates for each protein were not significantly different between these two groups. RA demonstrated significant upregulation of podoplanin at the invasive front (P 0.05). Immunolocalization for all four proteins was predominantly membranous and less frequently cytoplasmic. Pre-ameloblast-like cells were podoplanin(+) /CD44v6(-), while stellate reticulum-like cells were podoplanin(-)/CD44v6(+). Acanthomatous, granular cell, and desmoplastic variants in both RA and UPA were podoplanin(-/low) but stained weak-to-moderate for E-cadherin, β-catenin, and CD44v6. Stromal fibroblasts and lymph channels were variably podoplanin-positive. Podoplanin, β-catenin, and CD44v6 upregulation at the tumor invasive fronts in RA and UPA supports a differential regulatory role by these molecules in mediating collective cell migration and local invasiveness. E-cadherin downregulation suggests altered cell adhesion function during tumor progression. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. The role of E-cadherin - 160C/A polymorphism in breast cancer

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    Luo Gaojian

    2016-08-01

    Full Text Available Breast cancer is the most prevalent cancer in women worldwide. Numerous studies have suggested that the E-cadherin adhesion system is dysregulated in cancer cells. These impaired functions of E-cadherin contribute to releasing cancer cells from the primary lesion to cell dedifferentiation. Some studies have shown that polymorphism may affect E-cadherin expression, and then play a role in susceptibility to breast cancer. However, the results remained controversial. In this short review, we summarize the functions of E-cadherin and the signaling pathways it regulates, and assess the association between CDH1 polymorphisms and breast cancer susceptibility. This study suggests that genetic variation in CDH1 and -160C/A polymorphism may have an association with breast cancer risk. The assessment of CDH1 polymorphisms may be used for the identification of patients suitable for anti- CDH1 therapy.

  11. Reduced expression of E-cadherin/catenin complex in hepatocellular carcinomas

    Institute of Scientific and Technical Information of China (English)

    Bo Zhai; He-Xin Yan; Shu-Qin Wu; Lei Chen; Meng-Chao Wu; Hong-Yang Wang

    2008-01-01

    AIM: To examine the immunoreactivity of E-cadherin and four subtypes of catenin family in human hepatocellular carcinomas (HCCs) and to investigate the correlation between expression of E-cadherin/catenin complex and clinicopathologic parameters of HCC patients.METHODS: An immunohistochemical study for E-cadherin and catenins was performed on 97 formalin-fixed,paraffin-embedded specimens of HCC.RESULTS: Reduced expression of E-cadherin,α-,β-,γ-catenin and p120 was observed in 69%,76%,63%,71% and 73%,respectively.Both expressions of E-cadhedn and catenin components were significantly correlated with tumor grade (P = 0.000).It showed significant difference between expression of catenin members and tumor stage (P = 0.003,P = 0.017,P = 0.007 and P = 0.000,respectively).The reduced expression of E-cadherin in HCCs was significantly correlated with intrahepatic metastasis (IM) and capsular invasion (P = 0.008,P = 0.03,respectively).A close correlation was also observed between the expression of catenins and the tumor size (P = 0.002,P = 0.034,P = 0.016 and P = 0.000,respectively).In addition,the expression of each catenin was found correlated with IM (P = 0.012,P = 0.049,P =0.026 and P = 0.014,respectively).No statistically significant difference was observed between the expression level of E-cadherin/catenin complex and lymph node permission,vascular invasion and satellite nodules.Interestingly,only expression of p120 showed correlation with AFP value (P = 0.035).The expression of E-cadherin was consistent with α-,β-,γ-catenin and p120 expression (P = 0.000).Finally,the abnormal expression of E-cadherin/catenin complex was significantly associated with patients' survival (P= 0.0253,P = 0.0052,P = 0.003,P = 0.0105 and P= 0.0016,respectively).Nevertheless,no component of E-cadherin/catenin complex was the independent prognostic factor of HCC patients.CONCLUSION: Down-regulated expressions of E-cadherin,catenins and p120 occur frequently in HCCs and contribute to the

  12. E-cadherin is required for cranial neural crest migration in Xenopus laevis.

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    Huang, Chaolie; Kratzer, Marie-Claire; Wedlich, Doris; Kashef, Jubin

    2016-03-15

    The cranial neural crest (CNC) is a highly motile and multipotent embryonic cell population, which migrates directionally on defined routes throughout the embryo, contributing to facial structures including cartilage, bone and ganglia. Cadherin-mediated cell-cell adhesion is known to play a crucial role in the directional migration of CNC cells. However, migrating CNC co-express different cadherin subtypes, and their individual roles have yet to be fully explored. In previous studies, the expression of individual cadherin subtypes has been analysed using different methods with varying sensitivities, preventing the direct comparison of expression levels. Here, we provide the first comprehensive and comparative analysis of the expression of six cadherin superfamily members during different phases of CNC cell migration in Xenopus. By applying a quantitative RT-qPCR approach, we can determine the copy number and abundance of each expressed cadherin through different phases of CNC migration. Using this approach, we show for the first time expression of E-cadherin and XB/C-cadherin in CNC cells, adding them as two new members of cadherins co-expressed during CNC migration. Cadherin co-expression during CNC migration in Xenopus, in particular the constant expression of E-cadherin, contradicts the classical epithelial-mesenchymal transition (EMT) model postulating a switch in cadherin expression. Loss-of-function experiments further show that E-cadherin is required for proper CNC cell migration in vivo and also for cell protrusion formation in vitro. Knockdown of E-cadherin is not rescued by co-injection of other classical cadherins, pointing to a specific function of E-cadherin in mediating CNC cell migration. Finally, through reconstitution experiments with different E-cadherin deletion mutants in E-cadherin morphant embryos, we demonstrate that the extracellular domain, but not the cytoplasmic domain, of E-cadherin is sufficient to rescue CNC cell migration in vivo.

  13. Immunohistochemical evaluation of E-cadherin expression in basal cell carcinoma of the skin

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    Vladimír Bartoš

    2015-08-01

    Full Text Available Introduction: E-cadherin is important cell-cell adhesion molecule, that plays a crucial role in the maintenance of tissue microarchitecture. In many human malignancies, reduced or loss of E-cadherin production in neoplastic cells correlates with tumor dedifferentiation and acquisition of the invasive and metastatic potential. In contrast to most other cancers, basal cell carcinoma (BCC of the skin possess some unique features, such as slow local growth, strong stroma-dependency, and virtual absence of metastases. Aim: In the present study, we immunohistochemically evaluated expression of E-cadherin in a set of cutaneous BCCs. Material and methods: Study group consisted of 41 primary BCCs cathegorized into non-infiltrative subroup (superfical and nodular subtypes and infiltrative subroup (nodular-infiltrative and infiltrative subtypes. Results: E-cadherin was expressed in all tumor specimens with variable quantitative range and intensity. There were 19 cases (46.3 % with preserved and 22 cases (53.7 % with reduced E-cadherin expression. In superficial, nodular, nodular-infiltrative and infiltrative BCC subtypes, reduced E-cadherin immunoreactivity was found in 40 % (2/5, 56.2 % (9/16, 54.5 % (6/11 and 55.5 % (5/9, respectively. We did not confirm a significant correlation between expression of E-cadherin and both given, non-infiltrative and infiltrative BCC subgroup. None of the tumors examined showed apparent decreasing immunostaining intensity in tumor tissue with increasing depth of invasion. There were not convincing differences either between the central and peripheral parts of tumor mass, or in the vertical dimension. Conclusions: Reduction of E-cadherin expression per se does not seem to directly contribute to the acqusition of more aggressive phenotype in cutaneous BCC. This may represent another peculiarity, by which BCC differs from the most other epithelial malignancies and reflect a distinct tumor biology.

  14. Differential regulation of growth-promoting signalling pathways by E-cadherin.

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    Nikolaos T Georgopoulos

    Full Text Available BACKGROUND: Despite the well-documented association between loss of E-cadherin and carcinogenesis, as well as the link between restoration of its expression and suppression of proliferation in carcinoma cells, the ability of E-cadherin to modulate growth-promoting cell signalling in normal epithelial cells is less well understood and frequently contradictory. The potential for E-cadherin to co-ordinate different proliferation-associated signalling pathways has yet to be fully explored. METHODOLOGY/PRINCIPAL FINDINGS: Using a normal human urothelial (NHU cell culture system and following a calcium-switch approach, we demonstrate that the stability of NHU cell-cell contacts differentially regulates the Epidermal Growth Factor Receptor (EGFR/Extracellular Signal-Regulated Kinase (ERK and Phosphatidylinositol 3-Kinase (PI3-K/AKT pathways. We show that stable cell contacts down-modulate the EGFR/ERK pathway, whilst inducing PI3-K/AKT activity, which transiently enhances cell growth at low density. Functional inactivation of E-cadherin interferes with the capacity of NHU cells to form stable calcium-mediated contacts, attenuates E-cadherin-mediated PI3-K/AKT induction and enhances NHU cell proliferation by allowing de-repression of the EGFR/ERK pathway and constitutive activation of β-catenin-TCF signalling. CONCLUSIONS/SIGNIFICANCE: Our findings provide evidence that E-cadherin can differentially and concurrently regulate specific growth-related signalling pathways in a context-specific fashion, with direct, functional consequences for cell proliferation and population growth. Our observations not only reveal a novel, complex role for E-cadherin in normal epithelial cell homeostasis and tissue regeneration, but also provide the basis for a more complete understanding of the consequences of E-cadherin loss on malignant transformation.

  15. Soluble E-Cadherin: An Early Marker of Severity in Acute Pancreatitis

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    A. Sewpaul

    2009-01-01

    Full Text Available Background/Aims. At present, there is no simple test for predicting severity in acute pancreatitis. We investigated the use of an assay of soluble E-cadherin (sE-cadherin. Methods. Concentrations of sE-cadherin, from 19 patients with mild acute pancreatitis, 7 patients with severe acute pancreatitis, 11 patients with other acute gastrointestinal pathologies, and 12 healthy subjects were measured using a commercially available sandwich ELISA kit based on two monoclonal antibodies specific to the extracellular fragment of human E-cadherin. Measurements were made at 12 hours or less from onset of pain and also at 24 and 48 hours after onset of pain. Results. Mean (standard deviation concentration of sE-cadherin in patients with severe acute pancreatitis at <12 hours was 17780 ng/mL (7853, significantly higher than that of healthy volunteers 5180 ng/mL (1350, =.0039, patients with other gastrointestinal pathologies 7358 ng/mL (6655, =.0073, and also significantly higher than that of patients with mild pancreatitis, 7332 ng/mL (2843, =.0019. Discussion. Serum sE-cadherin could be an early (within 12 hours objective marker of severity in acute pancreatitis. This molecule warrants further investigation in the form of a large multicentre trial.

  16. Bioengineering a Single-Protein Junction.

    Science.gov (United States)

    Ruiz, Marta P; Aragones, Albert C; Camarero, Nuria; Vilhena, J G; Ortega, Maria; Zotti, Linda Angela; Perez, Ruben; Cuevas, Juan Carlos; Gorostiza, Pau; Díez-Pérez, Ismael

    2017-10-05

    Bioelectronics moves towards designing nanoscale electronic platforms that allow in vivo determinations. Such devices require interfacing complex biomolecular moieties as the sensing units to an electronic platform for signal transduction. Inevitably, a systematic design goes through a bottom-up understanding of the structurally related electrical signatures of the biomolecular circuit, which will ultimately lead us to tailor its electrical properties. Toward this aim, we show here the first example of bioengineered charge transport in a single-protein electrical contact. The results reveal that a single point-site mutation at the docking hydrophobic patch of a Cu-Azurin causes minor structural distortion of the protein blue Cu site and a dramatic change in the charge transport regime of the single-protein contact, which goes from the classical Cu-mediated 2-step transport in this system to a direct coherent tunneling. Our extensive spectroscopic studies and molecular-dynamics simulations show that the proteins' folding structures are preserved in the single-protein junction. The DFT-computed frontier orbital of the relevant protein segments suggests that the Cu center participation in each protein variant accounts for the different observed charge transport behavior. This work is a direct evidence of charge transport control in a protein backbone through external mutagenesis and a unique nanoscale platform to study structurally related biological electron transfer.

  17. Posttranslational modification of E-cadherin by core fucosylation regulates Src activation and induces epithelial-mesenchymal transition-like process in lung cancer cells.

    Science.gov (United States)

    Shao, Kang; Chen, Zhong Yi; Gautam, Suraj; Deng, Nian Hui; Zhou, You; Wu, Xing Zhong

    2016-02-01

    E-cadherin is often dysregulated in aggressive lung cancer, the mechanism of which cannot always be explained at the level of transcription. In 66 patients with lung cancer, immunohistochemical staining demonstrated that co-localization of E-cadherin and core fucose by Lens culinaris agglutinin was significantly less extensive in tumor than in nontumor tissue. Through gain and loss of fucosylation experiments in the giant lung carcinoma cell lines 95C and 95D, our results revealed that E-cadherin core fucosylation in 95C cells overexpressing α-1, 6-fucosyltransferase (Fut8) inhibited Fut8-95C cell migration, whereas knockdown of Fut8 in 95D cells enhanced migration of short-interfering RNA-targeting Fut8 (siFut8)-95D cells. The level of active Src (phosphorylated Src [Y416]) was significantly reduced in Fut8-95C cells, but elevated in siFut8-95D cells. In protein complexes immunoprecipitated from Fut8-95C cell lysates with anti-E-cadherin, less phosphorylated Src (Y416) and more β-catenin were observed, but immunoprecipitates from siFut8-95D cells, containing less core fucosylated E-cadherin, contained an elevated level of phospho-Src Y416. In Fut8-95C cells, phosphorylation of Akt (Y315, Y326) and GSK-3β (S9) was significantly reduced, but β-catenin (S37) phosphorylation was enhanced. Expression of N-cadherin and Snail1 was also reduced in Fut8-95C cells, but significantly increased in siFut8-95D cells. Intriguingly, when Src kinase activity was inhibited by treatment of cells with PP2 and SU6656, regulation of N-cadherin, Snail1 and cell migration by E-cadherin core fucosylation was abrogated in both Fut8-95C and siFut8-95D cells. Therefore, posttranslational modification of E-cadherin by less core fucosylation recruited and activated Src, and induced an epithelial-mesenchymal transition-like process in lung cancer cells.

  18. Lack of microRNA-101 causes E-cadherin functional deregulation through EZH2 up-regulation in intestinal gastric cancer.

    Science.gov (United States)

    Carvalho, Joana; van Grieken, Nicole C; Pereira, Patricia M; Sousa, Sónia; Tijssen, Marianne; Buffart, Tineke E; Diosdado, Begoña; Grabsch, Heike; Santos, Manuel A S; Meijer, Gerrit; Seruca, Raquel; Carvalho, Beatriz; Oliveira, Carla

    2012-09-01

    E-cadherin expression disruption is commonly observed in metastatic epithelial cancers and is a crucial step in gastric cancer (GC) initiation and progression. As aberrant expression of microRNAs often perturb the normal expression/function of pivotal cancer-related genes, we characterized and dissected a pathway that causes E-cadherin dysfunction via loss of microRNA-101 and up-regulation of EZH2 expression in GC. MicroRNA microarray expression profiling and array-CGH were used to reinforce miR-101 involvement in GC. By using quantitative real-time PCR and quantitative SNaPshot genomic PCR, we confirmed that miR-101 was significantly down-regulated in GC (p mucosas and, at least in 65% of the GC cases analysed, this down-regulation was caused by deletions and/or microdeletions at miR-101 genomic loci. Moreover, around 40% of cases showing miR-101 down-regulation displayed concomitant EZH2 over-expression (at the RNA and protein levels), which, in turn, was associated with loss/aberrant expression of E-cadherin. Interestingly, this occurred preferentially in intestinal-type GCs, retaining allele(s) untargeted by classical CDH1-inactivating mechanisms. We also demonstrated that miR-101 gain of function or direct inhibition of EZH2 in Kato III GC cells led to a strong depletion of endogenous EZH2 and consequent rescue of E-cadherin membranous localization, mimicking results obtained in clinical GC samples. In conclusion, we show that deletions and/or microdeletions at both miR-101 genomic loci cause mature miR-101 down-regulation, subsequent EZH2 over-expression and E-cadherin dysfunction, specifically in intestinal-type GC.

  19. E-cadherin gene hypermethylation and its protein expression in primary adenocarcinomas of the small bowel%原发性小肠腺癌中钙粘蛋白基因异常甲基化及蛋白表达的研究

    Institute of Scientific and Technical Information of China (English)

    李小燕; 黄缘; 宫亮

    2008-01-01

    Objective To investigate the methylation status of E-cadherin(E-cad)and its protein expression in human small bowel adenocarcinomas(SBAC),and the association of these findings with clinico-pathological characteristics.Methods E-cad gene hypermethylation and its protein expression in 36 patients with primary SBAC and the paired adjacent tissues were tested by methylation-specific PCR(MSP)assay and immunohistochemistry(IHC)respectively.Data associated with clinico-pathological characteristics was analyzed.Results The hypermethylation frequency of E-cad was 38.9% in cancerous tissues and 8.3% in adjacent tissues(P<0.01).The positive rate of E-cad expression was 41.7% in cancerous tissues and 97.2% in adjacent tissues(P<0.01).Twelve out of 21 cases without protein expression revealed methylated(P<0.01).Methylation status was closely related to E-cad protein expression in SBAC.The hypermethylation of E-cad gene and the expression Of E-cad protein were significantly correlated with the depth of invasion,the differentiation and lymph node metastasis(P<0.05),but were not correlated with other clinico-pathologic parameters such as age,sex,tumor size or location(P>0.05).Conclusions The hypermethylation of E-cad gene can down regulate the protein expression,which closely related to the depth of invasion,the differentiation and lymph node metastasis.%目的 探讨原发性小肠腺癌中钙粘蛋白(E-cad)基因甲基化状态和蛋白表达的特点,及其与小肠腺癌I临床病理特征的关系.方法 分别采用甲基化特异性PCR(MSP)和免疫组化SP法检测36例原发性小肠腺癌及相应癌旁组织中E-cad基因甲基化状态及蛋白表达水平,并结合临床资料进行分析.结果 小肠腺癌和癌旁组织中E-cad甲基化率分别为38.9%(14/36)和8.3%(3/36),差异有统计学意义(P<0.01).小肠腺癌和癌旁组织中E-cad蛋白的阳性率分别为41.7%(15/36)和97.2%(35/36),差异有统计学意义(P<0.01).E-cad蛋白缺失的21

  20. Hypoxia induced E-cadherin involving regulators of Hippo pathway due to HIF-1α stabilization/nuclear translocation in bone metastasis from breast carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Maroni, Paola [Istituto Ortopedico Galeazzi, IRCCS, Milano (Italy); Matteucci, Emanuela [Dipartiimento di Scienze Biomediche per la Salute, Molecular Pathology Laboratory, Università degli Studi di Milano, Milano (Italy); Drago, Lorenzo; Banfi, Giuseppe [Istituto Ortopedico Galeazzi, IRCCS, Milano (Italy); Dipartiimento di Scienze Biomediche per la Salute, Molecular Pathology Laboratory, Università degli Studi di Milano, Milano (Italy); Bendinelli, Paola [Dipartiimento di Scienze Biomediche per la Salute, Molecular Pathology Laboratory, Università degli Studi di Milano, Milano (Italy); Desiderio, Maria Alfonsina, E-mail: a.desiderio@unimi.it [Dipartiimento di Scienze Biomediche per la Salute, Molecular Pathology Laboratory, Università degli Studi di Milano, Milano (Italy)

    2015-01-15

    The present study deals with the molecular mechanisms involved in the regulation of E-cadherin expression under hypoxia, because the adjustment of the amount of E-cadherin due to physical stimuli of the microenvironment might influence the colonization of metastasis to skeleton. We analyzed the effect of 1% oxygen tension, that is similar to that encountered in the bone marrow by metastatic cells spreading from breast carcinoma. The purpose was to evaluate the hypoxia-orchestrated control of E-cadherin transactivation via hypoxia inducible factor-1 (HIF-1) and peroxisome proliferator activated receptor-γ (PPARγ), and the involvement of Hippo pathway members, as regulators of transcription factors. To give a translational significance to the study, we took into consideration human pair-matched ductal breast carcinoma and bone metastasis: E-cadherin and Wwox were expressed in bone metastasis but not in breast carcinoma, while HIF-1α and TAZ seemed localized principally in nuclei of metastasis and were found in all cell compartments of breast carcinoma. A close examination of the regulatory mechanisms underlying E-cadherin expression in bone metastasis was done in 1833 clone derived from MDA-MB231 cells. Hypoxia induced E-cadherin only in 1833 clone, but not in parental cells, through HIF-1 and PPARγ activities, while Wwox decreased. Since Wwox was highly expressed in bone metastasis, the effect of ectopic Wwox was evaluated, and we showed E-cadherin transactivation and enhanced invasiveness in WWOX transfected 1833 cells. Also, hypoxia was additive with ectopic Wwox remarkably enhancing HIF-1α nuclear shuttle and accumulation due to the lengthening of the half-life of HIF-1α protein; under this experimental condition HIF-1α appeared as a slower migrated band compared with control, in agreement with the phosphorylation state. The in vitro data strongly supported the almost exclusive presence of HIF-1α in nuclei of human-bone metastasis. Thus, we identified

  1. ID2 predicts poor prognosis in breast cancer, especially in triple-negative breast cancer, and inhibits E-cadherin expression

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    Li K

    2014-06-01

    Full Text Available Kai Li,1,2,* Ling Yao,1,* Li Chen,1,2 Zhi-Gang Cao,1,2 San-Jian Yu,1,2 Xia-Ying Kuang,1,2 Xin Hu,1 Zhi-Ming Shao1–31Department of Breast Surgery, Key Laboratory of Breast Cancer in Shanghai, Fudan University Shanghai Cancer Center, 2Department of Oncology, Shanghai Medical College, 3Institutes of Biomedical Science, Fudan University, Shanghai, People’s Republic of China *These authors have contributed equally to this work Background: Inhibitors of DNA-binding (ID proteins are known as important modulators in the regulation of cell proliferation and differentiation. This study sought to investigate the prognostic value of ID proteins in breast cancer. Methods: The prognostic role of ID proteins in human breast cancer was investigated in 250 breast cancers, via tissue microarrays. The messenger (mRNA and protein levels of E-cadherin were examined by quantitative reverse-transcription polymerase chain reaction (qRT-PCR and Western blotting, in cells overexpressing IDs. Dual-luciferase report assay was used to investigate the potential mechanism, and a migration assay was performed to investigate the influence of IDs on cell migratory activity. Results: The survival analysis with Kaplan–Meier and Cox regression showed that ID2 expression level, which correlated with estrogen receptor status and E-cadherin abundance, served as an independent prognostic factor for disease-free survival (DFS (P=0.013. The prognostic value of ID2 for DFS was most significant in triple-negative breast cancer patients (P=0.009. We also found that ID2 was negatively correlated with E-cadherin expression by correlation analysis (P=0.020, Pearson’s R=-0.155. Subsequently, we explored the biological rationale and uncovered that the enforced expression of ID proteins could suppress E-cadherin expression significantly, thus increasing the migration ability of mammary epithelial cells. Then using a combination of ID2 and E-cadherin expression, the patients were

  2. Aberrant E-cadherin and gamma-catenin expression in malignant mesothelioma and its diagnostic and biological relevance.

    Science.gov (United States)

    Orecchia, Sara; Schillaci, Francesca; Salvio, Michela; Libener, Roberta; Betta, Pier-Giacomo

    2004-08-01

    Cadherins and their associated cytoplasmic proteins, catenins, are critical to the maintenance of normal tissue integrity and the suppression of cancer invasion. The cadherin profile in malignant mesothelioma (MM) is not well defined and the role of the cadherin-catenin system in the pathogenesis of MM remains to be determined. By means of Western blot analysis and immunohistochemistry the expression of E (epithelial)-, N (neural)-, P (placental)-cadherin, and alpha-, beta- and gamma-catenins was studied in nine human MM cell lines and five human mesothelial cell lines. Mesothelial cells consistently expressed only N-cadherin and alpha- and beta-catenins. All but one MM cell line were N-cadherin-positive and all of them were also positive for alpha- and beta-catenins. E-cadherin was found in six (66.7%) and gamma-catenin in seven (77.8%) MM cell lines. Five of these E-cadherin-positive lines co-expressed N-cadherin and the remaining one was also P-cadherin-positive. Double immunofluorescence staining revealed the plasma membrane co-localisation of both cadherin types in MM cell lines that co-expressed E- and N-cadherin or E- and P-cadherin, respectively. Immunoprecipitation showed complexes of beta-catenin with both cadherin types when co-expressed. The results point to upregulation of E-cadherin and gamma-catenin in most MM cases and demonstrate that cadherin expression is more heterogeneous and less mutually exclusive in MM compared with the mesothelium, although the biological significance of this finding remains unclear.

  3. Dragon (repulsive guidance molecule RGMb) inhibits E-cadherin expression and induces apoptosis in renal tubular epithelial cells.

    Science.gov (United States)

    Liu, Wenjing; Li, Xiaoling; Zhao, Yueshui; Meng, Xiao-Ming; Wan, Chao; Yang, Baoxue; Lan, Hui-Yao; Lin, Herbert Y; Xia, Yin

    2013-11-01

    Dragon is one of the three members of the repulsive guidance molecule (RGM) family, i.e. RGMa, RGMb (Dragon), and RGMc (hemojuvelin). We previously identified the RGM members as bone morphogenetic protein (BMP) co-receptors that enhance BMP signaling. Our previous studies found that Dragon is highly expressed in the tubular epithelial cells of mouse kidneys. However, the roles of Dragon in renal epithelial cells are yet to be defined. We now show that overexpression of Dragon increased cell death induced by hypoxia in association with increased cleaved poly(ADP-ribose) polymerase and cleaved caspase-3 levels in mouse inner medullary collecting duct (IMCD3) cells. Dragon also inhibited E-cadherin expression but did not affect epithelial-to-mesenchymal transition induced by TGF-β in IMCD3 cells. Previous studies suggest that the three RGM members can function as ligands for the receptor neogenin. Interestingly, our present study demonstrates that the Dragon actions on apoptosis and E-cadherin expression in IMCD3 cells were mediated by the neogenin receptor but not through the BMP pathway. Dragon expression in the kidney was up-regulated by unilateral ureteral obstruction in mice. Compared with wild-type mice, heterozygous Dragon knock-out mice exhibited 45-66% reduction in Dragon mRNA expression, decreased epithelial apoptosis, and increased tubular E-cadherin expression and had attenuated tubular injury after unilateral ureteral obstruction. Our results suggest that Dragon may impair tubular epithelial integrity and induce epithelial apoptosis both in vitro and in vivo.

  4. E-cadherin and calretinin as immunocytochemical markers to differentiate malignant from benign serous effusions

    Institute of Scientific and Technical Information of China (English)

    Dong-Nan He; Hua-Sheng Zhu; Kun-He Zhang; Wen-Jian Jin; Wei-Ming Zhu; Ning Li; Jie-Shou Li

    2004-01-01

    AIM: To investigate the expressions of E-cadherin and calretinin in exfoliated cells of serous effusions and evaluate their values in distinguishing malignant effusions from benign ones.METHODS: Fresh serous effusion specimens werecentrifuged and exfoliated cells were collected. Cells were then processed with a standardized procedure, including paraformaldehyde fixation, BSA-PBS solution washing and smears preparation. E-cadherin and calretinin were detected by immunocytochemistry (ICC).RESULTS: In the exfoliated cells of serous effusions, most of carcinoma cells only expressed E-cadherin, and most of mesothelial cells only expressed calretinin, and benign cells (lymphocytes and granulocytes) did not express either of them. For E-cadherin, 85.7% (30/35) of malignant effusions and 8.1% (3/37) of benign fluids were ICC-positive (P<0.001).The sensitivity of E-cadherin ICC in the diagnosis of malignant effusions was 85.7%, specificity 91.9%, and diagnostic rate 88.9%. For calretinin, 94.6% (35/37) of benign effusions and 11.4% (4/35) of malignant effusions were ICC-positive (P<0.001). The sensitivity of calretinin ICC in the diagnosis of benign effusions was 94.6%,specificity 88.6%, and diagnostic rate 91.7%. For diagnosis of benign and malignant effusions by combining E-cadherin ICC and calretinin ICC, the specificities were up to 100%and 97.1%, respectively.CONCLUSION: E-cadherin ICC and calretinin ICC are sensitive and specific in differential diagnosis of benign and malignant serous effusion specimens and specificities are evidently improved when both markers are combined.

  5. CDH1/E-cadherin and solid tumors. An updated gene-disease association analysis using bioinformatics tools.

    Science.gov (United States)

    Abascal, María Florencia; Besso, María José; Rosso, Marina; Mencucci, María Victoria; Aparicio, Evangelina; Szapiro, Gala; Furlong, Laura Inés; Vazquez-Levin, Mónica Hebe

    2016-02-01

    Cancer is a group of diseases that causes millions of deaths worldwide. Among cancers, Solid Tumors (ST) stand-out due to their high incidence and mortality rates. Disruption of cell-cell adhesion is highly relevant during tumor progression. Epithelial-cadherin (protein: E-cadherin, gene: CDH1) is a key molecule in cell-cell adhesion and an abnormal expression or/and function(s) contributes to tumor progression and is altered in ST. A systematic study was carried out to gather and summarize current knowledge on CDH1/E-cadherin and ST using bioinformatics resources. The DisGeNET database was exploited to survey CDH1-associated diseases. Reported mutations in specific ST were obtained by interrogating COSMIC and IntOGen tools. CDH1 Single Nucleotide Polymorphisms (SNP) were retrieved from the dbSNP database. DisGeNET analysis identified 609 genes annotated to ST, among which CDH1 was listed. Using CDH1 as query term, 26 disease concepts were found, 21 of which were neoplasms-related terms. Using DisGeNET ALL Databases, 172 disease concepts were identified. Of those, 80 ST disease-related terms were subjected to manual curation and 75/80 (93.75%) associations were validated. On selected ST, 489 CDH1 somatic mutations were listed in COSMIC and IntOGen databases. Breast neoplasms had the highest CDH1-mutation rate. CDH1 was positioned among the 20 genes with highest mutation frequency and was confirmed as driver gene in breast cancer. Over 14,000 SNP for CDH1 were found in the dbSNP database. This report used DisGeNET to gather/compile current knowledge on gene-disease association for CDH1/E-cadherin and ST; data curation expanded the number of terms that relate them. An updated list of CDH1 somatic mutations was obtained with COSMIC and IntOGen databases and of SNP from dbSNP. This information can be used to further understand the role of CDH1/E-cadherin in health and disease.

  6. OF MICE AND MEN: DISSECTING THE INTERACTION BETWEEN LISTERIA MONOCYTOGENES INTERNALIN A AND E-CADHERIN

    Directory of Open Access Journals (Sweden)

    Samuel Genheden

    2013-03-01

    Full Text Available We report a study of the interaction between internalin A (inlA and human or murine E-cadherin (Ecad. inlA is used by Listeria monocytogenes to internalize itself into host cell, but the bacterium is unable to invade murine cells, which has been attributed to the difference in sequence between hEcad and mEcad. Using molecular dynamics simulations, MM/GBSA free energy calculations, hydrogen bond analysis, water characterization and umbrella sampling, we provide a complete atomistic picture of the binding between inlA and Ecad. We dissect key residues in the protein–protein interface and analyze the energetics using MM/GBSA.'From this analysis it is clear that the binding of inlA–mEcad is weaker than inlA–hEcad, on par with the experimentally observed inability of inlA to bind to mEcad.'However, extended MD simulations of 200 ns in length show no destabilization of the inlA–mEcad complex and the estimation of the potential of mean force (PMF using umbrella sampling corroborates this conclusion. The binding strength computed from the PMFs show no significant difference between the two protein complexes. Hence, our study suggests that the inability of L. monocytogenes to invade murine cells cannot be explained by processes at the nanosecond to sub-microsecond time scale probed by the simulations performed here.

  7. Nuclear translocation of Acinetobacter baumannii transposase induces DNA methylation of CpG regions in the promoters of E-cadherin gene.

    Directory of Open Access Journals (Sweden)

    Dong Chan Moon

    Full Text Available Nuclear targeting of bacterial proteins has emerged as a pathogenic mechanism whereby bacterial proteins induce host cell pathology. In this study, we examined nuclear targeting of Acinetobacter baumannii transposase (Tnp and subsequent epigenetic changes in host cells. Tnp of A. baumannii ATCC 17978 possesses nuclear localization signals (NLSs, (225RKRKRK(230. Transient expression of A. baumannii Tnp fused with green fluorescent protein (GFP resulted in the nuclear localization of these proteins in COS-7 cells, whereas the truncated Tnp without NLSs fused with GFP were exclusively localized in the cytoplasm. A. baumannii Tnp was found in outer membrane vesicles, which delivered this protein to the nucleus of host cells. Nuclear expression of A. baumannii Tnp fused with GFP in A549 cells induced DNA methylation of CpG regions in the promoters of E-cadherin (CDH1 gene, whereas the cytoplasmic localization of the truncated Tnp without NLSs fused with GFP did not induce DNA methylation. DNA methylation in the promoters of E-cadherin gene induced by nuclear targeting of A. baumannii Tnp resulted in down-regulation of gene expression. In conclusion, our data show that nuclear traffic of A. baumannii Tnp induces DNA methylation of CpG regions in the promoters of E-cadherin gene, which subsequently down-regulates gene expression. This study provides a new insight into the epigenetic control of host genes by bacterial proteins.

  8. Snail,E-cadherin 在结直肠癌中的表达及意义%Expression and Significance of Snail and E-cadherin in Colorectal Cancer

    Institute of Scientific and Technical Information of China (English)

    孙华聪; 阎宏; 李登欣; 刘丽荣

    2014-01-01

    目的:观察锌指转录因子(Snail)和上皮性钙粘附蛋白E-cadherin在结直肠癌组织中的表达情况,并探讨两者关系及意义。方法采用免疫组织化学PV9000法检测50例结直肠癌患者手术切除的肿瘤组织及20例癌旁正常结直肠组织中Snail,E-cadherin蛋白的表达。结果结直肠癌组织中Snail的阳性表达率明显高于癌旁正常结直肠组织(P<0.05),而结直肠癌组织中E-cadherin的阳性表达率显著低于癌旁正常结直肠组织(P<0.05);Snail和E-cad在结直肠癌组织中的表达均与癌组织的分化程度、浸润深度、临床分期、是否有淋巴结转移及远处器官转移密切相关(P<0.05);在结直肠癌组织中Snail与E-cadherin的表达呈负相关(P<0.05)。结论Snail和E-cadherin的异常表达与结直肠癌的发生、发展及侵袭转移密切相关,联合检测两种蛋白对于结直肠癌的早期诊断及预后判断有重要意义。%Objective To study the expression of Snail and E-cad protein in colorectal cancer,and to explore the relationship and significance between them .Methods The expression of Snail and E-cadherin protein was detected by using immunohistochemical PV9000 metheod in cases of surgical removal of the colorectal cancer tissue and cases of para -cancerous normal gastric tissue .Results The positive rate of Snail immunostaining in colorectal cancer was higher than that in adjacent normal colorectal tissue (P<0.05),and the posi-tive rate of E-cadherin immunostaining in colorectal cancer was lower than that in adjacent normal colorectal tissue (P<0.05).The expres-sion of Snail and E-cadherin in colorectal cancer tissue was closely related with the depth of tumor invasion ,differentiatial degree,clinical stage,lymph node metastases and distant metastases (P<0.05).There was negative correction between the expression of Snail and E-cadher-in protein in colorectal cancer (P<0.05).Conclusion The

  9. p63 and E-cadherin Expression in Canine Oral Squamous Cell Carcinoma.

    Science.gov (United States)

    Mestrinho, L A; Pissarra, H; Faísca, P B; Bragança, M; Peleteiro, M C; Niza, M M R E

    2015-07-01

    The expression of p63 and E-cadherin was studied in 22 oral squamous cell carcinomas in the dog according to immunohistochemical techniques. The association between these markers and clinicopathologic parameters was assessed. All tumor cells studied showed enhanced p63 expression. Regarding E-cadherin expression, 17 of 22 cases (77.3%) showed decreased immunoreactivity, and in 13 of 22 cases (59.1%), its expression was cytoplasmic. Neither p63 nor E-cadherin expression patterns were associated with tumor size, bone invasion, or lymph node metastasis. p63 score was related to proliferating cell nuclear antigen proliferative index (P = .020). A statistically significant correlation between the expression patterns of these 2 markers was noted (P = .026). Furthermore, they were related with tumor grade. An atypical p63 labeling and a cytoplasmic E-cadherin staining were statistically related with a higher tumor grade (P = .022 and P = .017, respectively). These findings suggest that changes in p63 and E-cadherin expression are frequent events in oral squamous cell carcinoma in dogs.

  10. E-cadherin determines Caveolin-1 tumor suppression or metastasis enhancing function in melanoma cells

    Science.gov (United States)

    Lobos-González, L; Aguilar, L; Diaz, J; Diaz, N; Urra, H; Torres, V; Silva, V; Fitzpatrick, C; Lladser, A; Hoek, K.S.; Leyton, L; Quest, AFG

    2013-01-01

    SUMMARY The role of caveolin-1 (CAV1) in cancer is highly controversial. CAV1 suppresses genes that favor tumor development, yet also promotes focal adhesion turnover and migration of metastatic cells. How these contrasting observations relate to CAV1 function in vivo is unclear. Our previous studies implicate E-cadherin in CAV1-dependent tumor suppression. Here we use murine melanoma B16F10 cells, with low levels of endogenous CAV1 and E-cadherin, to unravel how CAV1 affects tumor growth and metastasis, and to assess how co-expression of E-cadherin modulates CAV1 function in vivo in C57BL/6 mice. We find that overexpression of CAV1 in B16F10(cav-1) cells reduces subcutaneous tumor formation, but enhances metastasis relative to control cells. Furthermore, E-cadherin expression in B16F10(E-cad) cells reduces subcutaneous tumor formation, and lung metastasis when intravenously injected. Importantly, co-expression of CAV1 and E-cadherin in B16F10(cav1/E-cad) cells abolishes tumor formation, lung metastasis, increased Rac-1 activity and cell migration observed with B16F10(cav-1) cells. Finally, consistent with the notion that CAV1 participates in switching human melanomas to a more malignant phenotype, elevated levels of CAV1 expression correlated with enhanced migration and Rac-1 activation in these cells. PMID:23470013

  11. [Influencing of hep-2 cell function by RNAi silencing E-cadherin expression].

    Science.gov (United States)

    Tian, Jun; Li, Cheng-wen; Wu, Gui-qing; Sun, Jing; Chen, Qi

    2013-02-26

    To explore the function of human laryngeal carcinoma Hep-2 cell after down-regulating the expression of E-cadherin gene to provide theoretical rationales for gene therapy of laryngeal cancer. According to the GenBank database, 3 pairs of shRNA sequences of E-cadherin gene were designed and synthesized. shRNAs were transfected into the cell line Hep-2 by liposome. Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the silencing effect of E-cadherin expression. The changed capacity of cell proliferation were detected in vitro by methyl thiazolyl tetrazolium (MTT) assay in the transfected Hep-2 cells and the cell proliferation rate (survival rate) was calculated. And Transwell was used to detect the migratory capacity of Hep-2 cells after siRNA transfection. The E-cadherin gene expression of RNAi transfected Hep-2 cells significantly decreased in interference group. And the proliferation of interference group became markedly enhanced. In Transwell test, the migrated cell numbers in interference group were significant higher than those in negative control group (262 ± 15, 288 ± 12, 292 ± 6 vs 74 ± 8, all P Hep-2 cells. And E-cadherin may be considered as one of gene therapy targets for laryngeal cancer.

  12. Immunohistochemical Evaluation of p63, E-Cadherin, Collagen I and III Expression in Lower Limb Wound Healing under Honey

    Directory of Open Access Journals (Sweden)

    Ananya Barui

    2011-01-01

    Full Text Available Honey is recognized traditionally for its medicinal properties and also appreciated as a topical healing agent for infected and noninfected wounds. This study evaluates impact of honey-based occlusive dressing on nonhealing (nonresponding to conventional antibiotics traumatic lower limb wounds (n=34 through clinicopathological and immunohistochemical (e.g., expression of p63, E-cadherin, and Collagen I and III evaluations to enrich the scientific validation. Clinical findings noted the nonadherence of honey dressing with remarkable chemical debridement and healing progression within 11–15 days of postintervention. Histopathologically, in comparison to preintervention biopsies, the postintervention tissues of wound peripheries demonstrated gradual normalization of epithelial and connective tissue features with significant changes in p63+ epithelial cell population, reappearance of membranous E-cadherin (P<.0001, and optimum deposition of collagen I and III (P<.0001. Thus, the present study for the first time reports the impact of honey on vital protein expressions in epithelial and connective tissues during repair of nonhealing lower limb wounds.

  13. SLIT2 attenuation during lung cancer progression deregulates beta-catenin and E-cadherin and associates with poor prognosis.

    Science.gov (United States)

    Tseng, Ruo-Chia; Lee, Shih-Hua; Hsu, Han-Shui; Chen, Ben-Han; Tsai, Wan-Ching; Tzao, Ching; Wang, Yi-Ching

    2010-01-15

    Chromosome 4p15.3 is frequently deleted in late-stage lung cancer. We investigated the significance of the SLIT2 gene located in this region to lung cancer progression. SLIT2 encodes an extracellular glycoprotein that can suppress breast cancer by regulating beta-catenin. In this study, we examined alterations in the structure or expression of SLIT2, its receptor ROBO1, and beta-catenin, along with the AKT/glycogen synthase kinase 3beta (GSK3beta)/beta-transducin repeat-containing protein (betaTrCP) pathway in lung cancer cell lines and patients. Low SLIT2 expression correlated with an upward trend of pathological stage and poorer survival in lung cancer patients. Importantly, SLIT2, betaTrCP, and beta-catenin expression levels predicted postoperative recurrence of lung cancer in patients. Stimulating SLIT2 expression by various methods increased the level of E-cadherin caused by attenuation of its transcriptional repressor SNAI1. Conversely, knocking down SLIT2 expression increased cell migration and reduced cell adhesion through coordinated deregulation of beta-catenin and E-cadherin/SNAI1 in the AKT/GSK3beta/betaTrCP pathway. Our findings indicate that SLIT2 suppresses lung cancer progression, defining it as a novel "theranostic" factor with potential as a therapeutic target and prognostic predictor in lung cancer. Cancer Res; 70(2); 543-51.

  14. Expression of E-cadherin in primary oral squamous cell carcinoma and metastatic lymph nodes: An immunohistochemical study

    Directory of Open Access Journals (Sweden)

    Kaur Gurkiran

    2009-01-01

    Full Text Available Background: E-cadherin plays an important role in cell-to-cell adhesion and cell motility and its loss is associated with oral squamous cell carcinoma (OSCC progression. The aim of this study was to determine the expression of E-cadherin in various grades of OSCC and to correlate changes in the expression between these various grades and metastatic lymph nodes. Materials and Methods: Immunohistochemistry (IHC was used to detect E-cadherin expression in normal oral mucosa, primary OSCC ( n = 37, and metastatic lymph nodes ( n = 10. E-cadherin immunoreactivity was correlated with grades of differentiation and with clinicopathological features. Results: E-cadherin immunoreactivity was found to inversely correlate with the loss of cell differentiation. The expression of E-cadherin decreased significantly in advanced cases of OSCC. However, increase in E-cadherin immunoreactivity was seen in early lesions, that is, in well differentiated ( n = 9 and moderately differentiated OSCC ( n = 13. Furthermore, E-cadherin was negative in majority of metastatic lymph nodes (7/10. Conclusions: Loss of the cell adhesion and E-cadherin plays an important role in progression of OSCC, that is, down regulation of its expression is associated with de-differentiation and metastasis.

  15. E-cadherin expression increases cell proliferation by regulating energy metabolism through nuclear factor-κB in AGS cells.

    Science.gov (United States)

    Park, Song Yi; Shin, Jee-Hye; Kee, Sun-Ho

    2017-09-01

    β-Catenin is a central player in Wnt signaling, and activation of Wnt signaling is associated with cancer development. E-cadherin in complex with β-catenin mediates cell-cell adhesion, which suppresses β-catenin-dependent Wnt signaling. Recently, a tumor-suppressive role for E-cadherin has been reconsidered, as re-expression of E-cadherin was reported to enhance the metastatic potential of malignant tumors. To explore the role of E-cadherin, we established an E-cadherin-expressing cell line, EC96, from AGS cells that featured undetectable E-cadherin expression and a high level of Wnt signaling. In EC96 cells, E-cadherin re-expression enhanced cell proliferation, although Wnt signaling activity was reduced. Subsequent analysis revealed that nuclear factor-κB (NF-κB) activation and consequent c-myc expression might be involved in E-cadherin expression-mediated cell proliferation. To facilitate rapid proliferation, EC96 cells enhance glucose uptake and produce ATP using both mitochondria oxidative phosphorylation and glycolysis, whereas AGS cells use these mechanisms less efficiently. These events appeared to be mediated by NF-κB activation. Therefore, E-cadherin re-expression and subsequent induction of NF-κB signaling likely enhance energy production and cell proliferation. © 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

  16. High expression and prognostic role of CAP1 and CtBP2 in breast carcinoma: associated with E-cadherin and cell proliferation.

    Science.gov (United States)

    Liu, Xiancheng; Yao, Ninghua; Qian, Jing; Huang, Huiwei

    2014-03-01

    Overexpression of C-terminal binding protein-2 (CtBP2) has been noted to correlate with cancer metastasis in several human cancers including breast cancer. The aim of this study was to examine the effect of cyclase-associated protein 1 (CAP1) overexpression on CtBP2 expression and related mechanism in the metastasis of breast cancer. Immunohistochemical analysis was performed in 100 human breast carcinoma samples, and the data were correlated with clinicopathologic features. Furthermore, Western blot analysis was performed for CAP1 and CtBP2 in breast carcinoma samples and cell lines to evaluate their protein levels and molecular interaction. We found that the expression of CAP1 was positively related to CtBP2 expression (P<0.01); moreover, CAP1 expression was significantly correlated with histologic grade (P<0.01) and negatively related to E-cadherin expression (P<0.01). Meanwhile, CtBP2 expression obtained similar results. Kaplan-Meier survival analysis showed that overexpression of CAP1 and CtBP2 exhibited a significant correlation with poor prognosis in human breast cancer (P<0.01). While in vitro, we employed siRNA technique to knockdown CAP1 and CtBP2 expressions and observed their effects on MDA-MB-231 cells growth. CtBP2 depletion by siRNA-inhibited cell proliferation, resulted in increased E-cadherin levels. Moreover, knockdown of CAP1 resulted in decreased CtBP2 and increased E-cadherin expression. On the basis of these results, we suggested that CAP1's oncogenic abilities appear to be triggered at least in part by the modulation of CtBP2 and E-cadherin, which might serve as a future target for breast cancer.

  17. Intestinal trefoil factor controls the expression of the adenomatous polyposis coli-catenin and the E-cadherin-catenin complexes in human colon carcinoma cells.

    Science.gov (United States)

    Efstathiou, J A; Noda, M; Rowan, A; Dixon, C; Chinery, R; Jawhari, A; Hattori, T; Wright, N A; Bodmer, W F; Pignatelli, M

    1998-03-17

    Intestinal trefoil factor 3 (TFF3) is a member of the trefoil family of peptides, small molecules constitutively expressed in epithelial tissues, including the gastrointestinal tract. TFF3 has been shown to promote migration of intestinal epithelial cells in vitro and to enhance mucosal healing and epithelial restitution in vivo. In this study, we evaluated the effect of recombinant TFF3 (rTFF3) stimulation on the expression and cellular localization of the epithelial (E)-cadherin-catenin complex, a prime mediator of Ca2+ dependent cell-cell adhesion, and the adenomatous polyposis coli (APC)-catenin complex in HT29, HCT116, and SW480 colorectal carcinoma cell lines. Stimulation by rTFF3 (10(-9) M and 10(-8) M) for 20-24 hr led to cell detachment and to a reduction in intercellular adhesion in HT29 and HCT116 cells. In both cell lines, E-cadherin expression was down-regulated. The expression of APC, alpha-catenin and beta-catenin also was decreased in HT29 cells, with a translocation of APC into the nucleus. No change in either cell adhesion or in the expression of E-cadherin, the catenins, and APC was detected in SW480 cells. In addition, TFF3 induced DNA fragmentation and morphological changes characteristic of apoptosis in HT29. Tyrphostin, a competitive inhibitor of protein tyrosine kinases, inhibited the effects of TFF3. Our results indicate that by perturbing the complexes between E-cadherin, beta-catenin, and associated proteins, TFF3 may modulate epithelial cell adhesion, migration, and survival.

  18. Gap junction protein connexin-43 interacts directly with microtubules

    NARCIS (Netherlands)

    Giepmans, B N; Verlaan, I; Hengeveld, T; Janssen, H; Calafat, J; Falk, M M; Moolenaar, W H

    2001-01-01

    Gap junctions are specialized cell-cell junctions that mediate intercellular communication. They are composed of connexin proteins, which form transmembrane channels for small molecules [1, 2]. The C-terminal tail of connexin-43 (Cx43), the most widely expressed connexin member, has been implicated

  19. Negative correlation of LIV-1 and E-cadherin expression in hepatocellular carcinoma cells.

    Directory of Open Access Journals (Sweden)

    Rongxi Shen

    Full Text Available LIV-1, a zinc transporter, is a mediator downstream of STAT3 both in zebrafish and mammalian cells, and is involved in epithelial-mesenchymal transition (EMT. Despite LIV-1 participates in cancer growth and metastasis, little is known about the association of LIV-1 with human liver cancer development. Therefore, the expression of LIV-1 mRNA was analyzed by reverse transcriptase polymerase chain reaction (RT-PCR in 4 cultured cell lines (3 carcinoma and 1 normal liver cell lines, and the localization of LIV-1 protein was investigated by immunohistochemistry. Expression of LIV-1 protein was analyzed by Western blot both in 4 cultured cell lines and 120 liver tissues (100 carcinoma and 20 histologically normal tissues, and the relationship between its expression and clinicopathological finding was investigated in 100 hepatocellular carcinoma(HCC tissues. Then stable siRNA expressing Hep-G2 cells were generated to assess the function of LIV-1 in liver cancer cells. We found that LIV-1 mRNA was more highly expressed in liver cancer cell lines compared to normal liver cell line. Western blot showed the expression of LIV-1 was higher in 61% liver carcinoma tissues than that in normal liver tissues. Down-regulated LIV-1 cells showed significant inhibition of proliferation in vitro and reduction of tumor growth in vivo. Furthermore, E-cadherin expression increased in LIV-1 siRNA expressing Hep-G2. These findings indicated that LIV-1 may induce the EMT in HCC cells.

  20. Evaluation of methylation pattern in promoter region of E-cadherin ...

    African Journals Online (AJOL)

    user

    2011-03-07

    Mar 7, 2011 ... promoter methylation in CDH1 gene inactivation in breast cancer, the CpG methylation status of E- cadherin promoter ... The data indicate that CDH1 promoter methylation might be a potential ... Complex genetic and epigenetic alterations affect the ... DNA methylation is the covalent addition of a methyl.

  1. Expressions of Beta-catenin,E-cadherin and MMP-7 in Ovarian Epithelial Tumors

    Institute of Scientific and Technical Information of China (English)

    LIN Xiao; LI Yu; MI Can

    2008-01-01

    Objective:To investigate the expressions of Beta-catenin,E-cadherin and MMP-7 and their implications in ovarian epithelial tumor.Methods:lmmunohistochemicai staining with SP method was conducted to identify the expressions of Beta-catenin,E-cadherin and MMP-7 in ovarian epithelial tumor in 66 cases.Results:The abnormal expression rate of Beta-catenin in malignant ovarian epithelial tumor was higher than those in borderline and benign epithelial tumors(P<0.05).The positive rates of E-cadherin in benign and borderline ovarian epithelial tumors were significantly greater than that in malignant epithelial tumor.The expression rates of MMP-7 in malignant and borderline ovarian epithelial tumors were higher than that in benign epithelial tumor(P<0.05).Conclusion:The abnormal expressions of Beta-catenin,E-cadherin and MMP-7 might be used to indicate the malignance transform of ovarian epithelial tumors,but they have no significant correlation with peritoneal dropsy invasion,caul invasion and appendant invasion in ovarian epithelial tumor.

  2. Brain metastases from lung cancer show increased expression of DVL1, DVL3 and beta-catenin and down-regulation of E-cadherin.

    Science.gov (United States)

    Kafka, Anja; Tomas, Davor; Beroš, Vili; Pećina, Hrvoje Ivan; Zeljko, Martina; Pećina-Šlaus, Nives

    2014-06-13

    The susceptibility of brain to secondary formation from lung cancer primaries is a well-known phenomenon. In contrast, the molecular basis for invasion and metastasis to the brain is largely unknown. In the present study, 31 brain metastases that originated from primary lung carcinomas were analyzed regarding over expression of Dishevelled-1 (DVL1), Dishevelled-3 (DVL3), E-cadherin (CDH1) and beta-catenin (CTNNB1). Protein expressions and localizations were analyzed by immunohistochemistry. Genetic alterations of E-cadherin were tested by polymerase chain reaction (PCR)/loss of heterozygosity (LOH). Heteroduplex was used to investigate mutations in beta-catenin. DVL1 and DVL3 showed over expression in brain metastasis in 87.1% and 90.3% of samples respectively. Nuclear staining was observed in 54.8% of cases for DVL1 and 53.3% for DVL3. The main effector of the Wnt signaling, beta-catenin, was up-regulated in 56%, and transferred to the nucleus in 36% of metastases. When DVL1 and DVL3 were up-regulated the number of cases with nuclear beta-catenin significantly increased (p=0.0001). Down-regulation of E-cadherin was observed in 80% of samples. Genetic analysis showed 36% of samples with LOH of the CDH1. In comparison to other lung cancer pathologies, the diagnoses adenocarcinoma and small cell lung cancer (SCLC) were significantly associated to CDH1 LOH (p=0.001). Microsatellite instability was detected in one metastasis from adenocarcinoma. Exon 3 of beta-catenin was not targeted. Altered expression of Dishevelled-1, Dishevelled-3, E-cadherin and beta-catenin were present in brain metastases which indicates that Wnt signaling is important and may contribute to better understanding of genetic profile conditioning lung cancer metastasis to the brain.

  3. miR-5003-3p promotes epithelial-mesenchymal transition in breast cancer cells through Snail stabilization and direct targeting of E-cadherin.

    Science.gov (United States)

    Kwak, Seo-Young; Yoo, Je-Ok; An, Hyun-Ju; Bae, In-Hwa; Park, Myung-Jin; Kim, Joon; Han, Young-Hoon

    2016-06-09

    One of the initial steps in metastatic dissemination is the epithelial-mesenchymal transition (EMT). Along this line, microRNAs (miRNAs) have been shown to function as important regulators of tumor progression at various stages. Therefore, we performed a functional screening for EMT-regulating miRNAs and identified several candidate miRNAs. Among these, we demonstrated that miR-5003-3p induces cellular features characteristic of EMT. miR-5003-3p induced upregulation of Snail, a key EMT-promoting transcription factor and transcriptional repressor of E-cadherin, through protein stabilization. MDM2 was identified as a direct target of miR-5003-3p, the downregulation of which induced Snail stabilization. E-cadherin was also demonstrated to be a direct target of miR-5003-3p, reinforcing the EMT-promoting function of miR-5003-3p. In situ hybridization and immunohistochemical analyses using tissue microarrays revealed that miR-5003-3p expression was higher in paired metastatic breast carcinoma tissues than in primary ductal carcinoma tissues, and was inversely correlated with the expression of MDM2 and E-cadherin. Furthermore, miR-5003-3p enhanced the formation of metastatic nodules in the lungs of mice in a tail vein injection experiment. Collectively, our results suggest that miR-5003-3p functions as a metastasis activator by promoting EMT through dual regulation of Snail stability and E-cadherin, and may therefore be a potential therapeutic target in metastatic cancers. © The Author (2016). Published by Oxford University Press on behalf of Journal of Molecular Cell Biology, IBCB, SIBS, CAS. All rights reserved.

  4. Brain Metastases from Lung Cancer Show Increased Expression of DVL1, DVL3 and Beta-Catenin and Down-Regulation of E-Cadherin

    Directory of Open Access Journals (Sweden)

    Anja Kafka

    2014-06-01

    Full Text Available The susceptibility of brain to secondary formation from lung cancer primaries is a well-known phenomenon. In contrast, the molecular basis for invasion and metastasis to the brain is largely unknown. In the present study, 31 brain metastases that originated from primary lung carcinomas were analyzed regarding over expression of Dishevelled-1 (DVL1, Dishevelled-3 (DVL3, E-cadherin (CDH1 and beta-catenin (CTNNB1. Protein expressions and localizations were analyzed by immunohistochemistry. Genetic alterations of E-cadherin were tested by polymerase chain reaction (PCR/loss of heterozygosity (LOH. Heteroduplex was used to investigate mutations in beta-catenin. DVL1 and DVL3 showed over expression in brain metastasis in 87.1% and 90.3% of samples respectively. Nuclear staining was observed in 54.8% of cases for DVL1 and 53.3% for DVL3. The main effector of the Wnt signaling, beta-catenin, was up-regulated in 56%, and transferred to the nucleus in 36% of metastases. When DVL1 and DVL3 were up-regulated the number of cases with nuclear beta-catenin significantly increased (p = 0.0001. Down-regulation of E-cadherin was observed in 80% of samples. Genetic analysis showed 36% of samples with LOH of the CDH1. In comparison to other lung cancer pathologies, the diagnoses adenocarcinoma and small cell lung cancer (SCLC were significantly associated to CDH1 LOH (p = 0.001. Microsatellite instability was detected in one metastasis from adenocarcinoma. Exon 3 of beta-catenin was not targeted. Altered expression of Dishevelled-1, Dishevelled-3, E-cadherin and beta-catenin were present in brain metastases which indicates that Wnt signaling is important and may contribute to better understanding of genetic profile conditioning lung cancer metastasis to the brain.

  5. Cyclooxygenase-2 mediated regulation of E-cadherin occurs in conventional but not early-onset gastric cancer cell lines

    NARCIS (Netherlands)

    R. Sitarz; R.J. Leguit; W.W.J. de Leng; F.H.M. Morsink; W.P. Polkowski; R. Maciejewski; G.J.A. Offerhaus; A.N. Milne

    2009-01-01

    Background: COX-2 and E-cadherin, involved in invasion and metastasis, are molecules critical for gastric carcinogenesis. A relationship between them is documented in non-small cell lung and prostate cancer. We present novel evidence of a relationship between COX-2 and E-cadherin expression in gastr

  6. Cyclooxygenase-2 Mediated Regulation of E-Cadherin Occurs in Conventional But Not Early-Onset Gastric Cancer Cell Lines

    Directory of Open Access Journals (Sweden)

    R. Sitarz

    2009-01-01

    Full Text Available Background: COX-2 and E-cadherin, involved in invasion and metastasis, are molecules critical for gastric carcinogenesis. A relationship between them is documented in non-small cell lung and prostate cancer. We present novel evidence of a relationship between COX-2 and E-cadherin expression in gastric cancer.

  7. E-cadherin promotor methylation and mutation are inversely related to motility capacity of breast cancer cells

    NARCIS (Netherlands)

    Horssen, R. van; Hollestelle, A.; Rens, J.A.; Eggermont, A.M.; Schutte, M.; Ten Hagen, T.L.

    2012-01-01

    Inactivation of the tumor suppressor E-cadherin is an important event during breast tumorigenesis, as its decreased expression is linked to aggressiveness and metastasis. However, the relationship between the different modes of E-cadherin inactivation (mutation versus promotor hypermethylation) and

  8. Relationship between the Expression of E-cadherin and Microvessel Density in Lung Cancer and Its Significance

    Institute of Scientific and Technical Information of China (English)

    WANGXinyun; YANGJuhong; MAYing; CHENGBo; ZHENGHongwei; ZHENGHaiyan; ZHUCongzhong; LIUTing; LIYan; WANGAixiang; SUNCuiyun

    2005-01-01

    Objective: To study the relationship between the expression of E-cadherin and microvessel density (MVD) in lung cancer. Methods: The expression of E-cadherin and factor Ⅷ was detected in 104 lung cancer tissues by an immunohistochemical method, and MVD was calculated by an imageanalysis system. Results: The expression of E-cadherin was significantly related to the differentiation of lung cancers (P<0.05). A negative correlation was found between E-cadherin expression and MVD in lung cancer tissues (P=0.047). Conclusion: Down-expression of E-cadherin and an increase of MVD may play an important role in the invasion and metastasis of lung cancer, and may also be used as a useful marker for tumor prognosis.

  9. Maintenance and induction of murine embryonic stem cell differentiation using E-cadherin-Fc substrata without colony formation

    Institute of Scientific and Technical Information of China (English)

    Qing-Yuan MENG; Toshihiro AKAIKE

    2013-01-01

    Induced embryonic stem resources for the observation of the cell (ES) cells are expected to be promising cell behaviors in developmental biology as well as the implantation in cell treatments in human diseases. A recombinant E-cadherin substratum was developed as a cell recognizable substratum to maintain the ES cells' self-renewal and pluripotency at single cell level. Furthermore, the generation of various cell lineages in different germ layers, including hepatic or neural cells, was achieved on the chimeric protein layer precisely and effectively. The induction and isolation of specific cell population was carried out with the enhancing effect of other artificial extracellular matrices (ECMs) in enzyme-free process. The murine ES cell-derived cells showed highly morphological similarities and functional expressions to matured hepatocytes or neural progenitor cells.

  10. Maintenance and induction of murine embryonic stem cell differentiation using E-cadherin-Fc substrata without colony formation

    Science.gov (United States)

    Meng, Qing-Yuan; Akaike, Toshihiro

    2013-03-01

    Induced embryonic stem (ES) cells are expected to be promising cell resources for the observation of the cell behaviors in developmental biology as well as the implantation in cell treatments in human diseases. A recombinant E-cadherin substratum was developed as a cell recognizable substratum to maintain the ES cells' self-renewal and pluripotency at single cell level. Furthermore, the generation of various cell lineages in different germ layers, including hepatic or neural cells, was achieved on the chimeric protein layer precisely and effectively. The induction and isolation of specific cell population was carried out with the enhancing effect of other artificial extracellular matrices (ECMs) in enzyme-free process. The murine ES cell-derived cells showed highly morphological similarities and functional expressions to matured hepatocytes or neural progenitor cells.

  11. Group A Streptococcal Cysteine Protease Cleaves Epithelial Junctions and Contributes to Bacterial Translocation*

    Science.gov (United States)

    Sumitomo, Tomoko; Nakata, Masanobu; Higashino, Miharu; Terao, Yutaka; Kawabata, Shigetada

    2013-01-01

    Group A Streptococcus (GAS) is an important human pathogen that possesses an ability to translocate across the epithelial barrier. In this study, culture supernatants of tested GAS strains showed proteolytic activity against human occludin and E-cadherin. Utilizing various types of protease inhibitors and amino acid sequence analysis, we identified SpeB (streptococcal pyrogenic exotoxin B) as the proteolytic factor that cleaves E-cadherin in the region neighboring the calcium-binding sites within the extracellular domain. The cleaving activities of culture supernatants from several GAS isolates were correlated with the amount of active SpeB, whereas culture supernatants from an speB mutant showed no such activities. Of note, the wild type strain efficiently translocated across the epithelial monolayer along with cleavage of occludin and E-cadherin, whereas deletion of the speB gene compromised those activities. Moreover, destabilization of the junctional proteins was apparently relieved in cells infected with the speB mutant, as compared with those infected with the wild type. Taken together, our findings indicate that the proteolytic efficacy of SpeB in junctional degradation allows GAS to invade deeper into tissues. PMID:23532847

  12. PARP3 controls TGFβ and ROS driven epithelial-to-mesenchymal transition and stemness by stimulating a TG2-Snail-E-cadherin axis

    Science.gov (United States)

    Karicheva, Olga; Rodriguez-Vargas, José Manuel; Wadier, Nadège; Martin-Hernandez, Kathline; Vauchelles, Romain; Magroun, Najat; Tissier, Agnès; Schreiber, Valérie; Dantzer, Françoise

    2016-01-01

    Several members of the Poly(ADP-ribose) polymerase (PARP) family are essential regulators of genome integrity, actively prospected as drug targets for cancer therapy. Among them, PARP3 is well characterized for its functions in double-strand break repair and mitotis. Here we report that PARP3 also plays an integral role in TGFβ and reactive oxygen species (ROS) dependent epithelial-to-mesenchymal transition (EMT) and stem-like cell properties in human mammary epithelial and breast cancer cells. PARP3 expression is higher in breast cancer cells of the mesenchymal phenotype and correlates with the expression of the mesenchymal marker Vimentin while being in inverse correlation with the epithelial marker E-cadherin. Furthermore, PARP3 expression is significantly upregulated during TGFβ-induced EMT in various human epithelial cells. In line with this observation, PARP3 depletion alters TGFβ-dependent EMT of mammary epithelial cells by preventing the induction of the Snail-E-cadherin axis, the dissolution of cell junctions, the acquisition of cell motility and chemoresistance. PARP3 responds to TGFβ-induced ROS to promote a TG2-Snail-E-cadherin axis during EMT. Considering the link between EMT and cancer stem cells, we show that PARP3 promotes stem-like cell properties in mammary epithelial and breast cancer cells by inducing the expression of the stem cell markers SOX2 and OCT4, by increasing the proportion of tumor initiating CD44high/CD24low population and the formation of tumor spheroid bodies, and by promoting stem cell self-renewal. These findings point to a novel role of PARP3 in the control of TGFβ-induced EMT and acquisition of stem-like cell features and further motivate efforts to identify PARP3 specific inhibitors. PMID:27579892

  13. Epithelial self-healing is recapitulated by a 3D biomimetic E-cadherin junction

    NARCIS (Netherlands)

    Cohen, Daniel J.; Gloerich, Martijn; Nelson, W. James

    2016-01-01

    Epithelial monolayers undergo self-healing when wounded. During healing, cells collectively migrate into the wound site, and the converging tissue fronts collide and form a stable interface. To heal, migrating tissues must form cell-cell adhesions and reorganize from the front-rear polarity characte

  14. Trichomonas vaginalis perturbs the junctional complex in epithelial cells

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Trichomonas vaginalis, a protist parasite of the urogenital tract in humans, is the causative agent of trichomonosis,which in recent years have been associated with the cervical cancer development. In the present study we analyzed the modifications at the junctional complex level of Caco-2 cells after interaction with two isolates of T. vaginalis and the influence of the iron concentration present in the parasite's culture medium on the interaction effects. Our results show that T. vaginalis adheres to the epithelial cell causing alterations in the junctional complex, such as: (a) a decrease in transepithelial electrical resistance; (b) alteration in the pattern of junctional complex proteins distribution as obseryed for E-cadherin, occludin and ZO-1; and (c) enlargement of the spaces between epithelial cells. These effects were dependent on (a) the degree of the parasite virulence isolate, (b) the iron concentration in the culture medium, and (c) the expression of adhesin proteins on the parasite surface.

  15. Force via integrins but not E-cadherin decreases Oct3/4 expression in embryonic stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Uda, Yuhei [Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Department of Biomedical Engineering, Graduate School of Biomedical Engineering, Tohoku University, 6-6-01, Aramaki-aoba, Aoba-ward, Sendai City (Japan); Poh, Yeh-Chuin; Chowdhury, Farhan; Wu, Douglas C. [Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Tanaka, Tetsuya S. [Department of Animal Sciences, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Sato, Masaaki [Department of Biomedical Engineering, Graduate School of Biomedical Engineering, Tohoku University, 6-6-01, Aramaki-aoba, Aoba-ward, Sendai City (Japan); Wang, Ning, E-mail: nwangrw@illinois.edu [Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States)

    2011-11-18

    Highlights: Black-Right-Pointing-Pointer Force via integrins or cadherins induces similar cell stiffening responses. Black-Right-Pointing-Pointer Force via integrins but not cadherins induces cell spreading. Black-Right-Pointing-Pointer Force via integrins but not cadherins induces differentiation of embryonic stem cells. -- Abstract: Increasing evidence suggests that mechanical factors play a critical role in fate decisions of stem cells. Recently we have demonstrated that a local force applied via Arg-Gly-Asp (RGD) peptides coated magnetic beads to mouse embryonic stem (ES) cells increases cell spreading and cell stiffness and decreases Oct3/4 (Pou5f1) gene expression. However, it is not clear whether the effects of the applied stress on these functions of ES cells can be extended to natural extracellular matrix proteins or cell-cell adhesion molecules. Here we show that a local cyclic shear force applied via fibronectin or laminin to integrin receptors increased cell spreading and stiffness, downregulated Oct3/4 gene expression, and decreased cell proliferation rate. In contrast, the same cyclic force applied via cell-cell adhesion molecule E-cadherin (Cdh1) had no effects on cell spreading, Oct3/4 gene expression, and the self-renewal of mouse ES cells, but induced significant cell stiffening. Our findings demonstrate that biological responses of ES cells to force applied via integrins are different from those to force via E-cadherin, suggesting that mechanical forces might play different roles in different force transduction pathways to shape early embryogenesis.

  16. Caveolin-1, E-cadherin and β-catenin in Gastric Carcinoma, Precancerous Tissues and Chronic Non-atrophic Gastritis

    Institute of Scientific and Technical Information of China (English)

    Guo-yang Sun; Jun-xia Wu; Jian-sheng Wu; Yu-ting Pan; Rong Jin

    2012-01-01

    Objective:To investigate the expressions of caveolin-1,E-cadherin and β-catenin in gastric carcinoma,precancerous gastric and chronic non-atrophic gastritis tissues,and evaluate the correlation of these expressions with the development of gastric cancer.Methods:The expressions of caveolin-1,E-cadherin and β-catenin were detected by biotin-streptavidinperoxidase (SP) immunohistochemistry on 58 gastric cancer tissues,40 precancerous gastric tissues and 42 chronic non-atrophic gastritis tissues.The correlation between the expressions of caveolin-1,E-cadherin and β-catenin,and the clinicopathologic parameters of gastric cancer was analyzed retrospectively.Results:The positive rates of caveolin-1 and E-cadherin expressions in gastric carcinoma were significantly lower than precancerous gastric and chronic non-atrophic gastritis tissues (P<0.01).An abnormal rate of β-catenin expression in gastric carcinoma was higher than precancerous gastric and chronic non-atrophic gastritis tissues (P<0.01).Moreover,low expressions of caveolin-1,E-cadherin and β-catenin correlated with tumor size,depth of invasion,lymph node metastasis and TNM stage (P<0.05).The positive rates of caveolin-1 and E-cadherin expressions decreased (P<0.01),while an abnormal rate of β-catenin expression increased inversely,with the degree of atypical hyperplasia (P<0.01).Caveolin-1 expression correlated positively with E-cadherin (r=0.41,P<0.05).Caveolin-1 (r=-0.36,P<0.05) and E-cadherin (r=-0.45,P<0.05) expressions negatively correlated with abnormal β-catenin expression.Conclusion:These results suggested that dysregulated expressions of caveolin-1,E-cadherin and β-catenin correlated with the development of gastric cancer and its biological behavior.

  17. Bromodichloromethane induces cell proliferation in different tissues of male F344 rats by suppression of E-cadherin expression via hypermethylation or transcriptional activation of c-myc and cyclin D1.

    Science.gov (United States)

    Liao, Jing; Li, Xiao-Feng; Zhou, Shun-Chang; Luo, Yan; Liu, Ai-Lin; Lu, Wen-Qing

    2013-11-25

    The aim of this study was to investigate the mechanism of bromodichloromethane (BDCM) - induced cell proliferation in different tissues of male F344 rats. Rats were administered at doses of 0 and 100mg/kg/day BDCM dissolved in corn oil by gavage for 5 days/week for 1, 4, 8 and 12 weeks. Then the colon, kidney and liver were collected. No histologic lesions were observed in the colon of rats exposed to BDCM, while there were mild nephrotoxicity and marginal hepatotoxicity related to BDCM treatment. Moreover, BDCM enhanced cell proliferation in the colon and kidney but not in the liver. In colons, hypermethylation in E-cadherin promoter might be associated with inhibition of mRNA and protein expression after 12 weeks of BDCM exposure. In kidneys, BDCM decreased E-cadherin mRNA expression, accompanying with transcriptional activation of c-myc and cyclin D1. However, suppression of E-cadherin mRNA and protein expression occurred in the absence of significant changes in DNA methylation. Therefore, suppression of E-cadherin expression via hypermethylation or transcriptional activation of c-myc and cyclin D1 may be involved in BDCM-induced cell proliferation in different tissues of male F344 rats.

  18. Interleukin-32α induces migration of human melanoma cells through downregulation of E-cadherin.

    Science.gov (United States)

    Lee, Joohyun; Kim, Kyung Eun; Cheon, Soyoung; Song, Ju Han; Houh, Younkyung; Kim, Tae Sung; Gil, Minchan; Lee, Kyung Jin; Kim, Seonghan; Kim, Daejin; Hur, Dae Young; Yang, Yoolhee; Bang, Sa Ik; Park, Hyun Jeong; Cho, Daeho

    2016-10-04

    Interleukin (IL)-32α, the shortest isoform of proinflammatory cytokine IL-32, is associated with various inflammatory diseases and cancers. However, its involvement in human melanoma is not understood. To determine the effect of IL-32α in melanoma, IL-32α levels were examined in human melanoma cell lines that exhibit different migratory abilities. IL-32α levels were higher in human melanoma cell lines with more migratory ability. An IL-32α-overexpressing G361 human melanoma cell line was generated to investigate the effect of IL-32α on melanoma migration. IL-32α-overexpressing G361 cells (G361-IL-32α) exhibit an increased migratory ability compared to vector control cells (G361-vector). To identify factors involved in IL-32α-induced migration, we compared expression of E-cadherin in G361-vector and G361-IL-32α cells. We observed decreased levels of E-cadherin in G361-IL-32α cells, resulting in F-actin polymerization. To further investigate signaling pathways related to IL-32α-induced migration, we treated G361-vector and G361-IL-32α cells with PD98059, a selective MEK inhibitor. Inhibition of Erk1/2 by PD98059 restored E-cadherin expression and decreased IL-32α-induced migration. In addition, cell invasiveness of G361-IL-32α cells was tested using an in vivo lung metastasis model. As results, lung metastasis was significantly increased by IL-32α overexpression. Taken together, these data indicate that IL-32α induced human melanoma migration via Erk1/2 activation, which repressed E-cadherin expression. Our findings suggest that IL-32α is a novel regulator of migration in melanoma.

  19. α-Catenin and vinculin cooperate to promote high E-cadherin-based adhesion strength.

    Science.gov (United States)

    Thomas, William A; Boscher, Cécile; Chu, Yeh-Shiu; Cuvelier, Damien; Martinez-Rico, Clara; Seddiki, Rima; Heysch, Julie; Ladoux, Benoit; Thiery, Jean Paul; Mege, René-Marc; Dufour, Sylvie

    2013-02-15

    Maintaining cell cohesiveness within tissues requires that intercellular adhesions develop sufficient strength to support traction forces applied by myosin motors and by neighboring cells. Cadherins are transmembrane receptors that mediate intercellular adhesion. The cadherin cytoplasmic domain recruits several partners, including catenins and vinculin, at sites of cell-cell adhesion. Our study used force measurements to address the role of αE-catenin and vinculin in the regulation of the strength of E-cadherin-based adhesion. αE-catenin-deficient cells display only weak aggregation and fail to strengthen intercellular adhesion over time, a process rescued by the expression of αE-catenin or chimeric E-cadherin·αE-catenins, including a chimera lacking the αE-catenin dimerization domain. Interestingly, an αE-catenin mutant lacking the modulation and actin-binding domains restores cadherin-dependent cell-cell contacts but cannot strengthen intercellular adhesion. The expression of αE-catenin mutated in its vinculin-binding site is defective in its ability to rescue cadherin-based adhesion strength in cells lacking αE-catenin. Vinculin depletion or the overexpression of the αE-catenin modulation domain strongly decreases E-cadherin-mediated adhesion strength. This supports the notion that both molecules are required for intercellular contact maturation. Furthermore, stretching of cell doublets increases vinculin recruitment and α18 anti-αE-catenin conformational epitope immunostaining at cell-cell contacts. Taken together, our results indicate that αE-catenin and vinculin cooperatively support intercellular adhesion strengthening, probably via a mechanoresponsive link between the E-cadherin·β-catenin complexes and the underlying actin cytoskeleton.

  20. Syndecan-1 and E-cadherin expression in differentiated type of early gastric cancer

    Institute of Scientific and Technical Information of China (English)

    Mei-Fang Huang; You-Qing Zhu; Zhi-Fen Chen; Jun Xiao; Xin Huang; Yong-Yan Xiong; Gui-Fang Yang

    2005-01-01

    AIM: To elucidate the role and alterations of syndecan-1 and E-cadherin expression in different cellular phenotypes of differentiated-type gastric cancers (DGCs), METHODS: A total of 120 DGCs at an early stage, andtheir adjacent mucosa, were studied both by immunohistochemistry. Syndecan-1 and E-cadherin were assessed by immunohistochemical staining with anti-syndecan-1 and anti-E-cadherin antibodies, respectively. Based on immunohistochemistry, DGCs and their surrounding mucosa were divided into four types: gastric type (G-type),ordinary type (O-type), complete-intestinal type (CI-type),and null type (N-type).RESULTS: Syndecan-1 expression was significantly lower in G-type cancers (29.4%) than in O-type (79.6%) and CI-type cancers (90%) (P<0.05, respectively), but E-cadherin did not show this result. In addition, syndecan-1 expression was significantly reduced in DGCs comprised partly of poorly differentiated adenocarcinoma or signet-ring cell carcinoma, compared to DGCs demonstrating papillary and/or tubular adenocarcinoma (P<0.05). G-type intestinal metaplasia (IM) surrounding the tumors was observed in 23.8% of G-type, 4.9% of O-type, and 6.7% of CI-type cancers (P<0.05; G-type vs O-type). Reduction of syndecan-1 expression was significant in G-type IM (25%) compared to non-G-type IM (75%; P<0.05).CONCLUSION: Loss of syndecan-1 plays a role in the growth of G-type cancers of DGCs at an early stage, and the reduction of syndecan-1 expression in IM surrounding the tumors may influence the growth of G-type cancer.

  1. Notch1-Snail1-E-cadherin pathway in metastatic hepatocellular carcinoma.

    Science.gov (United States)

    Wang, Xiao Qi; Zhang, Wu; Lui, Eric L H; Zhu, Yongqiang; Lu, Ping; Yu, Xiaoming; Sun, Jisan; Yang, Sitian; Poon, Ronnie T P; Fan, Sheung Tat

    2012-08-01

    Notch signaling, a critical pathway for tissue development, also contributes to tumorigenesis in many cancers, but its pathological function in liver cancer is not well defined. In our study, Notch1 expression and its clinicopathological parameters were evaluated in 82 human hepatocellular carcinoma (HCC) patients. Plasmid-based siNotch1 shRNA was transiently or stably transfected into metastatic HCC cells and subsequently evaluated for the effects on orthotopic liver tumor metastasis in a mouse model as well as the effects on downstream pathways. Aberrant high expression of Notch1 was significantly associated with metastatic disease parameters in HCC patients, such as tumor-node-metastasis Stages III-IV and tumor venous invasion. Knocking-down Notch1 reduced cell motility in vitro and orthotopic tumor metastasis from the liver to the lung in vivo in a mouse model. In metastatic HCC cells, abnormal expression of Notch1 was associated with increased expression of Snail1 and repressed expression of E-cadherin; the Notch1-Snail1-E-cadherin association can also be found in HCC patient tumors. Inhibition of Notch1 by shRNA abolished Snail1 expression, which further resulted in the re-establishment of repressed E-cadherin in metastatic HCC cells. Thus, abnormal Notch1 expression was strongly associated with HCC metastatic disease, which might be mediated through the Notch1-Snail1-E-cadherin pathway. Knock-down of Notch1 reversed HCC tumor metastasis in a mouse model. Therefore, these data suggest that effective targeting of Notch signaling might also inhibit tumor metastasis.

  2. Endocytosis and Recycling of Tight Junction Proteins in Inflammation

    Directory of Open Access Journals (Sweden)

    Markus Utech

    2010-01-01

    Full Text Available A critical function of the epithelial lining is to form a barrier that separates luminal contents from the underlying interstitium. This barrier function is primarily regulated by the apical junctional complex (AJC consisting of tight junctions (TJs and adherens junctions (AJs and is compromised under inflammatory conditions. In intestinal epithelial cells, proinflammatory cytokines, for example, interferon-gamma (IFN-γ, induce internalization of TJ proteins by endocytosis. Endocytosed TJ proteins are passed into early and recycling endosomes, suggesting the involvement of recycling of internalized TJ proteins. This review summarizes mechanisms by which TJ proteins under inflammatory conditions are internalized in intestinal epithelial cells and point out comparable mechanism in nonintestinal epithelial cells.

  3. Probing E-cadherin endocytosis by morpholino-mediated Rab5 knockdown in zebrafish.

    Science.gov (United States)

    Ulrich, Florian; Heisenberg, Carl-Philipp

    2008-01-01

    The controlled internalization of membrane receptors and lipids is crucial for cells to control signaling pathways and interact with their environment. During clathrin-mediated endocytosis, membrane constituents are transported via endocytic vesicles into early endosomes, from which they are further distributed within the cell. The small guanosine triphosphatase (GTPase) Rab5 is both required and sufficient for the formation of these early endosomes and can be used to experimentally address endocytic processes. Recent evidence shows that endocytic turnover of E-cadherin regulates the migration of mesendodermal cells during zebrafish gastrulation by modulating their adhesive interactions with neighboring cells. This in turn leads to effective and synchronized movement within the embryo. In this review, we discuss techniques to manipulate E-cadherin endocytosis by morpholino-mediated knockdown of rab5 during zebrafish gastrulation. We describe the use of antibodies specifically directed against zebrafish E-cadherin to detect its intracellular localization and of in situ hybridization and primary cell culture to reveal patterns of cell migration and adhesion, respectively.

  4. Role of connexin43-interacting proteins at gap junctions

    NARCIS (Netherlands)

    Giepmans, Ben N G

    2006-01-01

    Gap junctions are arrays of cell-to-cell channels that allow diffusion of small molecules between neighboring cells. The individual channels are formed by the four-transmembrane connexin (Cx) proteins. Recently, multiple proteins have been found to interact at the cytoplasmic site with the most abun

  5. Role of connexin43-interacting proteins at gap junctions

    NARCIS (Netherlands)

    Giepmans, Ben N G

    2006-01-01

    Gap junctions are arrays of cell-to-cell channels that allow diffusion of small molecules between neighboring cells. The individual channels are formed by the four-transmembrane connexin (Cx) proteins. Recently, multiple proteins have been found to interact at the cytoplasmic site with the most

  6. Gene expression of WNTs, β-catenin and E-cadherin during the periimplantation period of pregnancy in pigs--involvement of steroid hormones.

    Science.gov (United States)

    Kiewisz, Jolanta; Kaczmarek, Monika M; Andronowska, Aneta; Blitek, Agnieszka; Ziecik, Adam J

    2011-09-01

    WNTs (wingless-type MMTV integration site family, member) are morphogenes considered as important factors taking part in uterus developmental processes and implantation. β-catenin is a downstream effector of WNTs action within the cell as well as, through E-cadherin, affecting epithelial organization and function. This study was conducted to investigate WNT4, WNT5A, WNT7A, β-catenin (CTNNB1) and E-cadherin (CDH1) gene expression and protein localization in the endometrium during the periimplantation period. Furthermore, the effect of 17β-estradiol (E(2)) and progesterone (P(4)) on WNTs, CTNNB1 and CDH1 gene expression in the porcine endometrium in vitro was examined. WNT4 protein was localized in the luminal and glandular epithelium as well as in the basal lamina of the uterine mucosa. WNT5A protein was detected only in the luminal epithelium. WNT7A, β-catenin and E-cadherin protein were identified both in the luminal and glandular epithelial cells, however, WNT7A protein immunoreactivity varied during respective days of estrous cycle and/or pregnancy. Despite unchanged expression of WNT4 mRNA in the endometrium of cyclic and early pregnant pigs, the negative influence of E(2) on WNT4 gene during in vitro experiment was observed. WNT4 and CDH1 gene expression was negatively correlated with blood plasma E(2) and P(4) level in uterine luminal flushings (ULFs) on Day 12 of pregnancy. Expression of WNT5A gene was up-regulated in the endometrium on Day 9 of pregnancy when compared to the respective day of the estrous cycle. A significant decrease of WNT7A gene expression and increase of CDH1 mRNA amount was detected on Day 12 of pregnancy. Overall, the results show the spatial localization of WNT4, WNT5A, WNT7A, β-catenin and E-cadherin proteins in porcine endometrium during periimplantation period of pregnancy and indicate significant changes of WNT5A, WNT7A and CDH1 gene expression before implantation in the pig.

  7. Distinct mesenchymal alterations in N-cadherin and E-cadherin positive primary renal epithelial cells.

    Directory of Open Access Journals (Sweden)

    Christof Keller

    Full Text Available BACKGROUND: Renal tubular epithelial cells of proximal and distal origin differ markedly in their physiological functions. Therefore, we hypothesized that they also differ in their capacity to undergo epithelial to mesenchymal alterations. RESULTS: We used cultures of freshly isolated primary human tubular cells. To distinguish cells of different tubular origin we took advantage of the fact that human proximal epithelial cells uniquely express N-cadherin instead of E-cadherin as major cell-cell adhesion molecule. To provoke mesenchymal alteration we treated these cocultures with TGF-β for up to 6 days. Within this time period, the morphology of distal tubular cells was barely altered. In contrast to tubular cell lines, E-cadherin was not down-regulated by TGF-β, even though TGF-β signal transduction was initiated as demonstrated by nuclear localization of Smad2/3. Analysis of transcription factors and miRNAs possibly involved in E-cadherin regulation revealed high levels of miRNAs of the miR200-family, which may contribute to the stability of E-cadherin expression in human distal tubular epithelial cells. By contrast, proximal tubular epithelial cells altered their phenotype when treated with TGF-β. They became elongated and formed three-dimensional structures. Rho-kinases were identified as modulators of TGF-β-induced morphological alterations. Non-specific inhibition of Rho-kinases resulted in stabilization of the epithelial phenotype, while partial effects were observed upon downregulation of Rho-kinase isoforms ROCK1 and ROCK2. The distinct reactivity of proximal and distal cells was retained when the cells were cultured as polarized cells. CONCLUSIONS: Interference with Rho-kinase signaling provides a target to counteract TGF-β-mediated mesenchymal alterations of epithelial cells, particularly in proximal tubular epithelial cells. Furthermore, primary distal tubular cells differed from cell lines by their high phenotypic stability

  8. Expression and localization of N- and E-cadherin in the human testis and epididymis

    DEFF Research Database (Denmark)

    Andersson, A M; Edvardsen, K; Skakkebaek, N E

    1994-01-01

    Cellular interactions in the testis and epididymis are an important prerequisite for spermatogenesis and sperm maturation, and involve a well-developed complex of intercellular junctions. Cadherins are cell surface proteins which mediate intercellular Ca(2+)-dependent adhesion and are believed...

  9. Expression of mucins and E-cadherin in gastric carcinoma and their clinical significance

    Institute of Scientific and Technical Information of China (English)

    Hong-Kai Zhang; Qiu-Min Zhang; Tie-Hua Zhao; Yuan-Yuan Li; Yong-Fen Yi

    2004-01-01

    AIM: To investigate the expression of three types of mucin (MUC1, MUC2, MUCSAC) and E-cadherin in human gastric carcinomas and their clinical significance.METHODS: Ninety-four gastric cancer specimens were classified according to WHO criteria and detected by immunohistochemical assay of expression of mucins and E-cadherin.RESULTS: The positive expression rates of MUC1, MUC2,MUC5AC and E-cadherin were 82% (77/94), 84% (79/94),40% (38/94) and 56% (53/94) respectively. MUC1 expression was significantly correlated with the types of cancer (the positive rates of MUC1 in well and moderately differentiated tubular adenocarcinoma, poorly differentiated adenocarcinoma,signet-ring cell carcinoma and mucinous carcinoma were 91%, 87%, 71%, 71%, respectively, P<0.05), age of patients (the positive rates of it among the people who are younger than 40 years, between 40-60 years and over 60 year were 74%, 81%, 89%, P<0.05), lymph nodes involvement (the positive rates in the non-interfered group and the interfered group were 78%, 85%, P<0.05) and tumor size (the positive rates in the tumors with the size less than 3 cm, 3-6 cm and larger than 6 cm were 69%, 92%, 69%, P<0.05); MUC2expression was significantly associated with types of cancers and had the strongest expression in mucinous carcinomas (the positive rates of MUC2 in well and moderately differentiated tubular adenocarcinoma, poorly differentiated adenocarcinoma,signet-ring cell carcinoma and mucinous carcinoma were 94%, 70%, 81%, 100%, P<0.05), but it had no obvious relation to age, gender, tumor location, lymph nodes involvement,depth of invasion and metastasis to extra-gastric organs (P>0.05); MUC5AC expression was not related to any of the characteristics investigated except that it had relation to gender, whereas MUC5AC showed the tendency to higher expression in less invasive lesions and lower expression in advanced stage cancers (P>0.05); No significant difference was found for E-cadherin expression

  10. The stardust family protein MPP7 forms a tripartite complex with LIN7 and DLG1 that regulates the stability and localization of DLG1 to cell junctions.

    Science.gov (United States)

    Bohl, Joanna; Brimer, Nicole; Lyons, Charles; Vande Pol, Scott B

    2007-03-30

    MPP7, a previously uncharacterized member of the p55 Stardust family of membrane-associated guanylate kinase (MAGUK) proteins, was found in a tripartite complex with DLG1 and LIN7A or LIN7C. MPP7 dimerizes with all three LIN7 family members (LIN7A, -B, and -C) through interaction of the single L27 domain of LIN7 with the carboxyl-terminal L27 domain of MPP7, thereby stabilizing both proteins. The dimer of MPP7 with LIN7A or LIN7C associates with DLG1 through an interaction requiring the amino-terminal L27 domain of MPP7. The amino-terminal L27 domain of MPP7 is not sufficient for interaction with DLG1 but interacts efficiently only if MPP7 is in a complex with LIN7A or -C. Thus the specificity of interaction of DLG1 with the LIN7-MPP7 complex is determined by L27 interactions with both MPP7 and LIN7. The tripartite complex forms in a ratio of 1:1:1 and localizes to epithelial adherens junctions in a manner dependent upon MPP7. Expression of MPP7 stabilizes DLG1 in an insoluble compartment. Expression of MPP7 deleted of the PDZ or Src homology 3 domain redistributes MPP7, DLG1, and LIN7 out of adherens junctions and into the soluble cytoplasmic fraction without changing the localization of E-cadherin. Thus, the stability and localization of DLG1 to cell-cell junctions are complex functions determined by the expression and association of particular Stardust family members together with particular LIN7 family members.

  11. Testosterone regulates tight junction proteins and influences prostatic autoimmune responses.

    Science.gov (United States)

    Meng, Jing; Mostaghel, Elahe A; Vakar-Lopez, Funda; Montgomery, Bruce; True, Larry; Nelson, Peter S

    2011-06-01

    Testosterone and inflammation have been linked to the development of common age-associated diseases affecting the prostate gland including prostate cancer, prostatitis, and benign prostatic hypertrophy. We hypothesized that testosterone regulates components of prostate tight junctions which serve as a barrier to inflammation, thus providing a connection between age- and treatment-associated testosterone declines and prostatic pathology. We examined the expression and distribution of tight junction proteins in prostate biospecimens from mouse models and a clinical study of chemical castration, using transcript profiling, immunohistochemistry, and electron microscopy. We determined that low serum testosterone is associated with reduced transcript and protein levels of Claudin 4 and Claudin 8, resulting in defective tight junction ultrastructure in benign prostate glands. Expression of Claudin 4 and Claudin 8 was negatively correlated with the mononuclear inflammatory infiltrate caused by testosterone deprivation. Testosterone suppression also induced an autoimmune humoral response directed toward prostatic proteins. Testosterone supplementation in castrate mice resulted in re-expression of tight junction components in prostate epithelium and significantly reduced prostate inflammatory cell numbers. These data demonstrate that tight junction architecture in the prostate is related to changes in serum testosterone levels, and identify an androgen-regulated mechanism that potentially contributes to the development of prostate inflammation and consequent pathology.

  12. Transitions of protein traffic from cardiac ER to junctional SR

    OpenAIRE

    Sleiman, Naama H.; McFarland, Timothy P.; Jones, Larry R.; Cala, Steven E.

    2015-01-01

    The junctional sarcoplasmic reticulum (jSR) is an important and unique ER subdomain in the adult myocyte that concentrates resident proteins to regulate Ca2+ release. To investigate cellular mechanisms for sorting and trafficking proteins to jSR, we overexpressed canine forms of junctin (JCT) or triadin (TRD) in adult rat cardiomyocytes. Protein accumulation over time was visualized by confocal fluorescence microscopy using species-specific antibodies. Newly synthesized JCTdog and TRDdog appe...

  13. Expression profile of E-cadherin, estrogen receptors, and P53 in early-onset gastric cancers.

    Science.gov (United States)

    Zhou, Fan; Xu, Yuanyuan; Shi, Jiong; Lan, Xing; Zou, Xiaoping; Wang, Lei; Huang, Qin

    2016-12-01

    Early-onset gastric cancer (EOGC) is predominant in females, diffuse histology, and hereditary pattern. Germline mutation of CDH1 and p53 has been reported previously and female dominance was speculated to be associated with estrogen and its receptors. Expression of E-cadherin, estrogen receptor α (ERα), estrogen receptor β (ERβ), and p53 in EOGC remains unclear, which was the focus of this study, to assess clinical significance of their expression in EOGC. The expression of E-cadherin, ERα, ERβ, and p53 in tumors and normal tissues from surgically resected EOGCs was assessed by immunohistochemistry (n = 139) and Western blot (n = 7) methods, respectively. The expression in tumor tissues was significantly higher for ERα, ERβ, and p53, but lower for E-cadherin, compared to uninvolved mucosa. Positive staining of ERβ and p53 was more frequently observed in younger patients with advanced TNM stages. For E-cadherin, significant correlation was observed between the immunopositivity and TNM stages IA+IB. P53-negative patients had significantly better outcomes than p53-positive patients. Significant association between expression of E-cadherin and histologic types was found in familial, but not in sporadic, EOGC. In conclusion, our results demonstrated E-cadherin may have a role in initiation of EOGC and positive ERβ and p53 expression may partially explained early-onset and tumor progression of EOGC.

  14. Microtubules Inhibit E-Cadherin Adhesive Activity by Maintaining Phosphorylated p120-Catenin in a Colon Carcinoma Cell Model.

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    Stephanie L Maiden

    Full Text Available Tight regulation of cadherin-mediated intercellular adhesions is critical to both tissue morphogenesis during development and tissue homeostasis in adults. Cell surface expression of the cadherin-catenin complex is often directly correlated with the level of adhesion, however, examples exist where cadherin appears to be inactive and cells are completely non-adhesive. The state of p120-catenin phosphorylation has been implicated in regulating the adhesive activity of E-cadherin but the mechanism is currently unclear. We have found that destabilization of the microtubule cytoskeleton, independent of microtubule plus-end dynamics, dephosphorylates p120-catenin and activates E-cadherin adhesion in Colo 205 cells. Through chemical screening, we have also identified several kinases as potential regulators of E-cadherin adhesive activity. Analysis of several p120-catenin phosphomutants suggests that gross dephosphorylation of p120-catenin rather than that of specific amino acids may trigger E-cadherin adhesion. Uncoupling p120-catenin binding to E-cadherin at the membrane causes constitutive adhesion in Colo 205 cells, further supporting an inhibitory role of phosphorylated p120-catenin on E-cadherin activity.

  15. Microtubules Inhibit E-Cadherin Adhesive Activity by Maintaining Phosphorylated p120-Catenin in a Colon Carcinoma Cell Model.

    Science.gov (United States)

    Maiden, Stephanie L; Petrova, Yuliya I; Gumbiner, Barry M

    2016-01-01

    Tight regulation of cadherin-mediated intercellular adhesions is critical to both tissue morphogenesis during development and tissue homeostasis in adults. Cell surface expression of the cadherin-catenin complex is often directly correlated with the level of adhesion, however, examples exist where cadherin appears to be inactive and cells are completely non-adhesive. The state of p120-catenin phosphorylation has been implicated in regulating the adhesive activity of E-cadherin but the mechanism is currently unclear. We have found that destabilization of the microtubule cytoskeleton, independent of microtubule plus-end dynamics, dephosphorylates p120-catenin and activates E-cadherin adhesion in Colo 205 cells. Through chemical screening, we have also identified several kinases as potential regulators of E-cadherin adhesive activity. Analysis of several p120-catenin phosphomutants suggests that gross dephosphorylation of p120-catenin rather than that of specific amino acids may trigger E-cadherin adhesion. Uncoupling p120-catenin binding to E-cadherin at the membrane causes constitutive adhesion in Colo 205 cells, further supporting an inhibitory role of phosphorylated p120-catenin on E-cadherin activity.

  16. Role of caspase-3/E-cadherin in helicobacter pylori-induced apoptosis of gastric epithelial cells.

    Science.gov (United States)

    Yang, Yongmei; Du, Jie; Liu, Fen; Wang, Xiaoyan; Li, Xiaohui; Li, Yuanjian

    2017-08-29

    This study was designed to investigate the role of caspase-3/E-cadherin in Helicobacter pylori (H. pylori) -induced gastric epithelial apoptosis in cells, animal models and clinical gastritis patients. In cultured gastric mucosal epithelial cells, gastric glandular epithelial cells and C57BL/6 mice, H. pylori infection significantly induced apoptosis of gastric epithelial cells, down-regulated full-length E-cadherin and Bcl-2 expression, and up-regulated cleaved-caspase-3, E-cadherin/carboxy-terminal fragment 3 and Bax expression. Z-DEVD-FMK, an inhibitor of caspase-3, attenuated the effect of H. pylori. E-cadherin overexpression significantly inhibited the apoptosis of GES-1 and SGC-7901 cells induced by the H. pylori. The results from clinical studies also showed down-regulation of E-cadherin, up-regulation of cleaved-caspase-3 expression and increased apoptosis in gastric tissues from gastritis patients with H. pylori infection. These results suggest that the caspase-3/E-cadherin pathway is involved in the apoptosis of gastric epithelial cells induced by H. pylori.

  17. Establishment of an ovarian metastasis model and possible involvement of E-cadherin down-regulation in the metastasis.

    Science.gov (United States)

    Kuwabara, Yoshiko; Yamada, Taketo; Yamazaki, Ken; Du, Wen-Lin; Banno, Kouji; Aoki, Daisuke; Sakamoto, Michiie

    2008-10-01

    Clinical observations of cases of ovarian metastasis suggest that there may be a unique mechanism underlying ovarian-specific metastasis. This study was undertaken to establish an in vivo model of metastasis to the ovary, and to investigate the mechanism of ovarian-specific metastasis. We examined the capacity for ovarian metastasis in eight different human carcinoma cell lines by implantation in female NOD/SCID mice transvenously and intraperitoneally. By transvenous inoculation, only RERF-LC-AI, a poorly differentiated carcinoma cell line, frequently demonstrated ovarian metastasis. By intraperitoneal inoculation, four of the eight cell lines (HGC27, MKN-45, KATO-III, and RERF-LC-AI) metastasized to the ovary. We compared E-cadherin expression among ovarian metastatic cell lines and others. All of these four ovarian metastatic cell lines and HSKTC, a Krukenberg tumor cell line, showed E-cadherin down-regulation and others did not. E-cadherin was then forcibly expressed in RERF-LC-AI, and inhibited ovarian metastasis completely. The capacity for metastasizing to the other organs was not affected by E-cadherin expression. We also performed histological investigation of clinical ovarian-metastatic tumor cases. About half of all ovarian-metastatic tumor cases showed loss or reduction of E-cadherin expression. These data suggest that E-cadherin down-regulation may be involved in ovarian-specific metastasis.

  18. Molecular mechanisms involved in TFF3 peptide-mediated modulation of the E-cadherin/catenin cell adhesion complex.

    Science.gov (United States)

    Meyer zum Büschenfelde, Dirk; Hoschützky, Heinz; Tauber, Rudolf; Huber, Otmar

    2004-05-01

    TFF3 is a member of the TFF-domain peptide family which is constitutively expressed in mucous epithelial tissues where it acts as a motogenic factor and plays an important role during epithelial restitution after wounding and during inflammation. In contrast to these beneficial functions, TFFs were also reported to be involved in cell scattering and tumor invasion. These changes in epithelial cell morphology and motility are associated with a modulation of cell contacts. In this respect, we here investigated the E-cadherin/catenin cell adhesion complex in FLAG-hTFF3-transfected HT29/B6 and MDCK cells. In hTFF3-transfected cells the amount of E-cadherin is reduced with a concomitant reduction of alpha- and beta-catenin levels. On one hand, E-cadherin expression is lowered at the transcriptional level as shown by multiplex RT-PCR analysis. This decrease does not depend on differences in the promoter methylation status as shown by methylation-specific PCR. On the other hand, pulse-chase experiments showed a reduction in the E-cadherin half-life in hTFF3-transfected cells reflecting increased E-cadherin degradation. In summary, hTFF3 induces transcriptional and posttranslational processes resulting in a modulation of E-cadherin-mediated cell-cell contacts that may play an important role in the paradoxical benefical and pathogenic function of TFF peptides.

  19. Nectin/PRR: an immunoglobulin-like cell adhesion molecule recruited to cadherin-based adherens junctions through interaction with Afadin, a PDZ domain-containing protein.

    Science.gov (United States)

    Takahashi, K; Nakanishi, H; Miyahara, M; Mandai, K; Satoh, K; Satoh, A; Nishioka, H; Aoki, J; Nomoto, A; Mizoguchi, A; Takai, Y

    1999-05-03

    We have isolated a novel actin filament-binding protein, named afadin, localized at cadherin-based cell-cell adherens junctions (AJs) in various tissues and cell lines. Afadin has one PDZ domain, three proline-rich regions, and one actin filament-binding domain. We found here that afadin directly interacted with a family of the immunoglobulin superfamily, which was isolated originally as the poliovirus receptor-related protein (PRR) family consisting of PRR1 and -2, and has been identified recently to be the alphaherpes virus receptor. PRR has a COOH-terminal consensus motif to which the PDZ domain of afadin binds. PRR and afadin were colocalized at cadherin-based cell-cell AJs in various tissues and cell lines. In E-cadherin-expressing EL cells, PRR was recruited to cadherin-based cell-cell AJs through interaction with afadin. PRR showed Ca2+-independent cell-cell adhesion activity. These results indicate that PRR is a cell-cell adhesion molecule of the immunoglobulin superfamily which is recruited to cadherin-based cell-cell AJs through interaction with afadin. We rename PRR as nectin (taken from the Latin word "necto" meaning "to connect").

  20. Expression and significance of APC,β-catenin and E-cadherin proteins in colorectal carcinoma%结肠腺瘤性息肉蛋白、β-连接素和E-钙黏素在大肠癌中的表达

    Institute of Scientific and Technical Information of China (English)

    戴文斌; 任占平; 陈蔚麟; 杜娟; 石喆; 唐德艳

    2008-01-01

    目的:探讨结肠腺瘤性息肉蛋白(APC)、β-连接素(β-catenin)和E-钙黏素(E-cadherin)在大肠癌发生、发展中的作用.方法:采用免疫组化方法检测30例正常大肠黏膜、30例大肠腺瘤、10例大肠腺瘤恶变及50例大肠癌组织中APC、β-catenin和E-cadherin蛋白的表达情况.结果:大肠癌和大肠腺瘤恶变APC阳性率分别为44.0%,40.0%,显著低于大肠腺瘤(86.7%)和正常大肠黏膜(100%).大肠癌、大肠腺瘤恶变和大肠腺瘤β-catenin胞浆(胞核)异位表达率分别为62.0%,50.0%,30.0%,显著高于正常大肠黏膜(0%),大肠癌β-catenin异位表达率显著高于大肠腺瘤.大肠癌中β-catenin、E-cadherin膜表达缺失率为46.0%,34.0%,显著高于大肠腺瘤(10.0%,6.67%)和正常大肠黏膜(0%,0%),且与大肠癌组织分化程度、浸润深度、淋巴结转移、Dukes分期有关.APC蛋白表达与大肠癌组织分化程度有关.大肠癌中β-catenin异位表达与APC阳性表达呈负相关关系;β-catenin与E-cadherin胞膜阳性表达呈正相关关系.结论:APC失表达和(或)β-catenin异位表达与大肠癌的发生密切相关,可能是大肠癌发生的早期事件;β-catenin、E-cadherin膜表达缺失与大肠癌的侵袭、转移有关.

  1. Characterization of ascites-derived ovarian tumor cells from spontaneously occurring ovarian tumors of the chicken: evidence for E-cadherin upregulation.

    Directory of Open Access Journals (Sweden)

    Anupama Tiwari

    Full Text Available Ovarian cancer, a highly metastatic disease, is the fifth leading cause of cancer-related deaths in women. Chickens are widely used as a model for human ovarian cancer as they spontaneously develop epithelial ovarian tumors similar to humans. The cellular and molecular biology of chicken ovarian cancer (COVCAR cells, however, have not been studied. Our objectives were to culture COVCAR cells and to characterize their invasiveness and expression of genes and proteins associated with ovarian cancer. COVCAR cell lines (n = 13 were successfully maintained in culture for up to19 passages, cryopreserved and found to be viable upon thawing and replating. E-cadherin, cytokeratin and α-smooth muscle actin were localized in COVCAR cells by immunostaining. COVCAR cells were found to be invasive in extracellular matrix and exhibited anchorage-independent growth forming colonies, acini and tube-like structures in soft agar. Using RT-PCR, COVCAR cells were found to express E-cadherin, N-cadherin, cytokeratin, vimentin, mesothelin, EpCAM, steroidogenic enzymes/proteins, inhibin subunits-α, βA, βB, anti-müllerian hormone, estrogen receptor [ER]-α, ER-β, progesterone receptor, androgen receptor, and activin receptors. Quantitative PCR analysis revealed greater N-cadherin, vimentin, and VEGF mRNA levels and lesser cytokeratin mRNA levels in COVCAR cells as compared with normal ovarian surface epithelial (NOSE cells, which was suggestive of epithelial-mesenchymal transformation. Western blotting analyses revealed significantly greater E-cadherin levels in COVCAR cell lines compared with NOSE cells. Furthermore, cancerous ovaries and COVCAR cell lines expressed higher levels of an E-cadherin cleavage product when compared to normal ovaries and NOSE cells, respectively. Cancerous ovaries were found to express significantly higher ovalbumin levels whereas COVCAR cell lines did not express ovalbumin thus suggesting that the latter did not originate from

  2. Slit2-Robo1 signaling promotes the adhesion, invasion and migration of tongue carcinoma cells via upregulating matrix metalloproteinases 2 and 9, and downregulating E-cadherin

    Science.gov (United States)

    Zhao, Yuan; Zhou, Feng-Li; Li, Wei-Ping; Wang, Jing; Wang, Li-Jing

    2016-01-01

    Whether Slit homologue 2 (Slit2) inhibits or promotes tumor cell migration remains controversial, and the role of Slit2-Roundabout 1 (Robo1) signaling in oral cancer remains to be fully elucidated. The aim of the present study was to investigate the role of Slit2-Robo1 signaling in the adhesion, invasion and migration of tongue carcinoma cells, and the mechanism by which Slit2-Robo1 signaling inhibits or promotes tumor cell migration. Tca8113 tongue carcinoma cells were treated with the monoclonal anti-human Robo1 antibody, R5, to inhibit the Slit2-Robo1 signaling pathway, with immunoglobulin (Ig)G2b treatment as a negative control. The expression levels of Slit2 and Robo1 were determined using flow cytometry. The effects of R5 on the adhesion, invasion and migration of Tca8113 tongue carcinoma cells were investigated. Gelatin zymography was used to investigate the activity of matrix metalloproteinase 2 (MMP2) and MMP9. Western blot analysis was used to evaluate the expression levels of E-cadherin in Tca8113 cells treated with 10 µg/ml of either R5 or IgG2b. Slit2 and Robo1 proteins were found to be expressed in the Tca8113 cells. R5 significantly inhibited the adhesion, invasion and migration of Tca8113 cells in vitro. R5 also inhibited the activities of MMP2 and MMP9, and increased the expression of E-cadherin in the Tca8113 cells. These results suggested that Slit2-Robo1 signaling promoted the adhesion, invasion and migration of tongue carcinoma cells by upregulating the expression levels of MMP2 and MMP9 and, downregulating the expression of E-cadherin. PMID:27431199

  3. The expression of E-cadherin-catenin complex in patients with advanced gastric cancer: role in formation of metastasis.

    Directory of Open Access Journals (Sweden)

    Marek Ustymowicz

    2010-06-01

    Full Text Available The E-cadherin-catenin complex plays an important role in the process of cell adhesion. Its dysfunction is associated with a decrease in cell differentiation and with increased invasiveness and metastasis. Our aim was to evaluate the expression of E-cadherin and B-catenin in advanced gastric cancer in relation to selected clinico-pathomorphological parameters. Formalin-fixed, paraffin-embedded tissue specimens were immunohistochemically stained with monoclonal antibodies E-cadherin (NCL-E-Cad, Novocastra Laboratiries Ltd; dilution 1:50, beta-catenin (NCL-B-CAT, Novocastra Laboratories Ltd; dilution 1:100, alpha-catenin (alpha-E-caten, Santa Cruz Biotechnology; dilution 1:300 and gamma-catenin (gamma-catenin, Santa Cruz Biotechnology; dilution 1:100. The expressions of E-cadherin and alpha-, beta-, gamma-catenins in the main mass of tumor and lymph node metastasis were investigated in 91 patients with gastric cancer. No statistically significant correlation was observed between the expressions of E-cadherin, alpha-, beta-catenins and histological differentiation and between the expressions of E-cadherin, alpha-, gamma-catenins and location or depth of invasion. Moreover, the expression of alpha-, gamma-catenins in the main mass of tumor was not associated with lymph node metastasis. However, we found a relationship between the expression of beta-catenin in the main mass of tumor and lymph node metastasis and tumor location. The depth of invasion was correlated with positive expression of beta-catenin in the main mass of gastric cancer. A statistically significant association was observed between the expressions of E-cadherin and beta-catenin in the main mass of tumor and lymph node involvement. The expression of alpha-catenin in the main mass of tumor was also associated with histological differentiation and Lauren's classification. Statistical analysis showed an association between the expression of E-cadherin and postoperative survival time. No

  4. Syndecan-2 enhances E-cadherin shedding and fibroblast-like morphological changes by inducing MMP-7 expression in colon cancer cells.

    Science.gov (United States)

    Jang, Bohee; Jung, Hyejung; Chung, Heesung; Moon, Byung-In; Oh, Eok-Soo

    2016-08-12

    E-cadherin plays a mechanical role in mediating cell-cell interactions and maintaining epithelial tissue integrity, and the loss of E-cadherin function has been implicated in cancer progression and metastasis. Syndecan-2, a cell-surface heparan sulfate proteoglycan, is upregulated during the development of colon cancer. Here, we assessed the functional relationship between E-cadherin and syndecan-2. We found that stable overexpression of syndecan-2 in a human colorectal adenocarcinoma cell line (HT29) enhanced the proteolytic shedding of E-cadherin to conditioned-media. Either knockdown of matrix metalloproteinase 7 (MMP-7) or inhibition of MMP-7 activity using GM6001 significantly reduced the extracellular shedding of E-cadherin, suggesting that syndecan-2 mediates E-cadherin shedding via MMP-7. Consistent with this notion, enhancement of MMP-7 expression by interleukin-1α treatment increased the shedding of E-cadherin. Conversely, the specific reduction of either syndecan-2 or MMP-7 reduced the shedding of E-cadherin. HT29 cells overexpressing syndecan-2 showed significantly lower cell-surface expression of E-cadherin, decreased cell-cell contact, a more fibroblastic cell morphology, and increased expression levels of ZEB-1. Taken together, these data suggest that syndecan-2 induces extracellular shedding of E-cadherin and supports the acquisition of a fibroblast-like morphology by regulating MMP-7 expression in a colon cancer cell line.

  5. Alteration in synaptic junction proteins following traumatic brain injury.

    Science.gov (United States)

    Merlo, Lucia; Cimino, Francesco; Angileri, Filippo Flavio; La Torre, Domenico; Conti, Alfredo; Cardali, Salvatore Massimiliano; Saija, Antonella; Germanò, Antonino

    2014-08-15

    Extensive research and scientific efforts have been focused on the elucidation of the pathobiology of cellular and axonal damage following traumatic brain injury (TBI). Conversely, few studies have specifically addressed the issue of synaptic dysfunction. Synaptic junction proteins may be involved in post-TBI alterations, leading to synaptic loss or disrupted plasticity. A Synapse Protein Database on synapse ontology identified 109 domains implicated in synaptic activities and over 5000 proteins, but few of these demonstrated to play a role in the synaptic dysfunction after TBI. These proteins are involved in neuroplasticity and neuromodulation and, most importantly, may be used as novel neuronal markers of TBI for specific intervention.

  6. Nuclear factor I-C (NFIC) regulates dentin sialophosphoprotein (DSPP) and E-cadherin via control of Krüppel-like factor 4 (KLF4) during dentinogenesis.

    Science.gov (United States)

    Lee, Hye-Kyung; Lee, Dong-Seol; Park, Su-Jin; Cho, Kwang-Hee; Bae, Hyun-Sook; Park, Joo-Cheol

    2014-10-10

    Odontoblasts are a type of terminally differentiated matrix-secreting cells. A number of molecular mechanisms are involved in the differentiation of odontoblasts. Several studies demonstrated that Krüppel-like factor 4 (KLF4) promotes odontoblast differentiation via control of dentin sialophosphoprotein (DSPP). Because nuclear factor I-C (NFIC) is also known to control DSPP, we investigated the relationship between NFIC and KLF4 during odontoblast differentiation. Klf4 mRNA expression was significantly decreased in Nfic(-/-) pulp cells compared with wild type cells. In immunohistochemistry assays, dentin matrix protein 1 (Dmp1), and DSP protein expression was barely observed in Nfic(-/-) odontoblasts and dentin matrix. Nfic bound directly to the Klf4 promoter and stimulated Klf4 transcriptional activity, thereby regulating Dmp1 and DSPP expression during odontoblast differentiation. Nfic or Klf4 overexpression promoted mineralized nodule formation in MDPC-23 cells. In addition, Nfic overexpression also decreased Slug luciferase activity but augmented E-cadherin promoter activity via up-regulation of Klf4 in odontoblasts. Our study reveals important signaling pathways during dentinogenesis: the Nfic-Klf4-Dmp1-Dspp and the Nfic-Klf4-E-cadherin pathways in odontoblasts. Our results indicate the important role of NFIC in regulating KLF4 during dentinogenesis.

  7. E-cadherin promotes incorporation of mouse epiblast stem cells into normal development.

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    Satoshi Ohtsuka

    Full Text Available Mouse epiblast stem cells (mEpiSCs are pluripotent stem cells derived from epiblasts of postimplantation mouse embryos. Their pluripotency is distinct from that of mouse embryonic stem cells (mESCs in several cell biological criteria. One of the distinctions is that mEpiSCs contribute either not at all or at much lower efficiency to chimeric embryos after blastocyst injection compared to mESCs. However, here we showed that mEpiSCs can be incorporated into normal development after blastocyst injection by forced expression of the E-cadherin transgene for 2 days in culture. Using this strategy, mEpiSCs gave rise to live-born chimeras from 5% of the manipulated blastocysts. There were no obvious signs of reprogramming of mEpiSCs toward the mESC-like state during the 2 days after induction of the E-cadherin transgene, suggesting that mEpiSCs possess latent ability to integrate into the normal developmental process as its origin, epiblasts.

  8. E-cadherin promotes incorporation of mouse epiblast stem cells into normal development.

    Science.gov (United States)

    Ohtsuka, Satoshi; Nishikawa-Torikai, Satomi; Niwa, Hitoshi

    2012-01-01

    Mouse epiblast stem cells (mEpiSCs) are pluripotent stem cells derived from epiblasts of postimplantation mouse embryos. Their pluripotency is distinct from that of mouse embryonic stem cells (mESCs) in several cell biological criteria. One of the distinctions is that mEpiSCs contribute either not at all or at much lower efficiency to chimeric embryos after blastocyst injection compared to mESCs. However, here we showed that mEpiSCs can be incorporated into normal development after blastocyst injection by forced expression of the E-cadherin transgene for 2 days in culture. Using this strategy, mEpiSCs gave rise to live-born chimeras from 5% of the manipulated blastocysts. There were no obvious signs of reprogramming of mEpiSCs toward the mESC-like state during the 2 days after induction of the E-cadherin transgene, suggesting that mEpiSCs possess latent ability to integrate into the normal developmental process as its origin, epiblasts.

  9. Status of p16(INK4a) and E-cadherin gene promoter methylation in Moroccan patients with cervical carcinoma.

    Science.gov (United States)

    Attaleb, Mohammed; El hamadani, Wail; Khyatti, Meriem; Benbacer, Laila; Benchekroun, Nadia; Benider, Abdellatif; Amrani, Mariam; El Mzibri, Mohammed

    2009-01-01

    Aberrant methylation of tumor suppressor gene promoters has been extensively investigated in cervical cancer. Transcriptional silencing, as a main consequence of hypermethylation of CpG islands, is the predominant mechanism of p16(INK4a) and E-cadherin gene inactivation in malignant epithelial tumors. This study was conducted to evaluate the promoter methylation status of p16(INK4a) and E-cadherin genes in 22 specimens of cervical carcinomas, four cervical cancer cell lines (HeLa, SiHa, Caski, C33A), and 20 human papillomavirus negative specimens, obtained from normal cervical swabs, using the methylation-specific PCR approach. Hypermethylation of the 5' CpG island of the p16(INK4a) and E-cadherin genes were found in 13 (59.1%) and 10 (45.5%) of 22 cervical cancer samples, respectively. Furthermore, our findings did not show any correlation between promoter methylation of p16(INK4a) and E-cadherin genes and clinicopathological parameters, including HPV infection, phenotypic distribution, and stage of the disease. However, hypermethylation of E-cadherin gene promoter appears to be age related in cervical cancer, whereas the frequency of aberrant methylation of p16(INK4a) gene promoter is unchanged according to the age of patients. Thus, caution must be made to use these markers in the diagnosis of cervical cancer. However, dietary or pharmaceutical agents that can inhibit these epigenetic events may prevent or delay the development of cervical cancer.

  10. Genetic variation of the E-cadherin gene is associated with primary infertility in patients with ovarian endometriosis.

    Science.gov (United States)

    Kang, Shan; Li, Yan; Li, Bin; Wang, Na; Zhou, Rong-Miao; Zhao, Xi-Wa

    2014-10-01

    To explore the association between the genetic variant of E-cadherin gene and endometriosis-related infertility. Case-control study. University hospital. Five hundred eighty-nine women with ovarian endometriosis including 127 patients with primary infertility and 589 female controls in northern China. None. Single nucleotide polymorphisms (SNPs) in the promoter region, exons, and the 3' untranslated region of the E-cadherin gene were identified by direct sequencing in patients with ovarian endometriosis and with polymerase chain reaction (PCR). Six candidate SNPs (rs16260, rs28372783, rs1801552, rs1801026, rs8049282, and rs13689) were genotyped by PCR and ligase detection reaction. The results revealed a significant association of rs8049282 SNP on E-cadherin gene with endometriosis-related infertility. When compared with control women or endometriosis patients who had a history of successful fertility, the CC genotype of rs8049282 may significantly increase the risk of primary infertility in patients with ovarian endometriosis (adjusted odds ratio [OR] = 2.70, 95% confidence interval [CI] 1.45-5.00; OR = 2.54, 95% CI 1.45-4.44, respectively). Our results suggested that genetic variants on the E-cadherin gene may be involved in endometriosis-related infertility. The rs8049282 SNP of the E-cadherin gene may be a potential molecular marker for the development of primary infertility in northern Chinese women with ovarian endometriosis. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  11. E-cadherin gene-engineered feeder systems for supporting undifferentiated growth of mouse embryonic stem cells.

    Science.gov (United States)

    Horie, Masanobu; Ito, Akira; Kiyohara, Takehiko; Kawabe, Yoshinori; Kamihira, Masamichi

    2010-11-01

    Conventionally, embryonic stem (ES) cells are cultured on a cell layer of mouse embryonic fibroblasts (MEFs) as feeder cells to support undifferentiated growth of ES cells. In this study, cell-cell interactions between mouse ES and feeder cells were artificially engineered via an epithelial cell adhesion molecule, E-cadherin, whose expression is considerable in ES cells. Mouse mesenchymal STO and NIH3T3 cells that were genetically engineered to express E-cadherin were used in ES cell cultures as feeder cells. ES cells cultured on the E-cadherin-expressing feeder cells maintained the expression of stem cell markers, alkaline phosphatase (AP), Oct3/4, Nanog and Sox2, and the efficiency of AP-positive colony formation was comparable to MEFs, and much better than parental STO and NIH3T3 cells. Furthermore, ES cells maintained on the E-cadherin-expressing feeder cells possessed the ability to differentiate into the three germ layers both in vitro and in vivo. The results indicated that E-cadherin expression in feeder cells could improve the performance of feeder cells, which may be further applicable to create new artificial feeder cell lines.

  12. Lactobacilli inhibit cervical cancer cell migration in vitro and reduce tumor burden in vivo through upregulation of E-cadherin.

    Science.gov (United States)

    Li, Xiaoxi; Wang, Hong; Du, Xingxing; Yu, Wenna; Jiang, Jingwen; Geng, Yanhong; Guo, Xiaobing; Fan, Xiuhua; Ma, Cuiqing

    2017-09-01

    The present study was designed to investigate the antitumor effects of Lactobacillus and the potential mechanisms. Cell Counting Kit-8 (CCK-8) assays were carried out to determine suitable doses for investigating the inhibitory effect of lactobacilli on cell migration ability of HeLa and U14 cells in vitro. In addition, western blot assays were performed to investigate the possible mechanisms corresponding to its antitumor effects. Furthermore, a xenograft mouse model was established for investigating the E-cadherin expression in tumor tissues after treatment with lactobacilli. Our results showed that live lactobacilli [multiplicity of infection (MOI) of 1,000:1] significantly possessed inhibitory effects on cell migration ability of cervical cancer cells. Lactobacilli (MOI: 1,000:1) significantly upregulated E-cadherin expressions in HeLa and U14 cells (p<0.05). On the contrary, our results showed that inactivated lactobacilli could not affect the E-cadherin expression levels in HeLa and U14 cells. Similar to the western blot assay, immunohistochemistry results also indicated that lactobacilli treatment significantly upregulated E-cadherin in tumor tissues (p<0.05). In conclusion, our results above suggest that lactobacilli have the potential for inhibiting the migratory ability of cervical cancer cell lines, and the possible pharmacological mechanism may be closely related to the upregulation of E-cadherin.

  13. No association exists between E-cadherin gene polymorphism and tumor recurrence in patients with hepatocellular carcinoma after transplantation

    Institute of Scientific and Technical Information of China (English)

    Xiao-Dong Li; Shu-Sen Zheng; Li-Ming Wu; Hai-Yang Xie; Xiao Xu; Lin Zhou; Ting-Bo Liang; Wei-Lin Wang; Yan Shen; Min Zhang

    2007-01-01

    BACKGROUND: E-cadherin is an epithelial cell adhesion molecule, and decreased E-cadherin expression in liver cancer is associated with poor prognosis. A -160 C→A polymorphism in the promoter region of E-cadherin has been reported to decrease gene transcription. This allelic variation may be a potential genetic marker for identifying those individuals at higher risk for invasive/metastatic disease. METHODS: The effect of E-cadherin gene polymorphism on risk of tumor recurrence was studied in 93 patients with hepatocellular carcinoma (HCC) after liver transplantation, and determined whether this polymorphism is a biomarker for the risk of tumor recurrence. RESULTS: The genotype frequencies in the patients with recurrence were C/C: 0.667, C/A: 0.311, and A/A:0.022, and in the patients without recurrence C/C:0.604, C/A: 0.271 and A/A: 0.125. No signiifcant difference was found between the two groups (P=0.171). Between -160 C→A polymorphism and the clinicopathological data, there were no statistically signiifcant differences in the distribution of the parameters as to age, gender, portal vein tumor thrombi, preoperative alpha-fetoprotein level, tumor size, or histopathological grading (P>0.05). CONCLUSION:The results of this study show no association exists between the E-cadherin genotype and the risk of tumor recurrence in Chinese patients with HCC.

  14. Colorectal adenocarcinoma with mucinous component: relation of MMP-13, EGFR, and E-cadherin expressions to clinicopathological features and prognosis.

    Science.gov (United States)

    Foda, Abd Al-Rahman Mohammad; El-Hawary, Amira Kamal; Aziz, Azza Abdel

    2015-06-01

    The aim of this study was to compare colorectal adenocarcinoma with mucinous component, ordinary adenocarcinoma (OA) and mucinous adenocarcinoma (MA) regarding clinicopathological parameters, survival, EGFR, MMP-13, and E-cadherin. We studied tumor tissue specimens from 28 patients with adenocarcinoma with mucinous component, 47 with OA, and 56 with MA, who underwent radical surgery from January 2007 to January 2012 at the Gastroenterology Centre, Mansoura University, Egypt. High density manual tissue microarrays were constructed and immunohistochemistry for EGFR, MMP-13, and E-cadherin was done. Colorectal adenocarcinoma with mucinous component (AWMC) was significantly associated with more perineural invasion, lower EGFR, and MMP-13 expressions than OA, with no difference in E-cadherin expression. Conversely, only microscopic abscess formation was significantly more with colorectal AWMC than MC with no difference in EGFR, MMP-13 and E-cadherin expression between both groups. Colorectal AWMC showed a better survival than MA with no difference with OA. In a univariate analysis, EGFR, MMP-13, and E-cadherin expressions did not show a significant impact on disease-free or overall survival in patients with colorectal AWMC. Colorectal AWMC remains a vague entity that resembles OA in some clinicopathological and molecular respects as well as MA. © 2015 APMIS. Published by John Wiley & Sons Ltd.

  15. Campylobacter jejuni outer membrane vesicle-associated proteolytic activity promotes bacterial invasion by mediating cleavage of intestinal epithelial cell E-cadherin and occludin.

    Science.gov (United States)

    Elmi, Abdi; Nasher, Fauzy; Jagatia, Heena; Gundogdu, Ozan; Bajaj-Elliott, Mona; Wren, Brendan; Dorrell, Nick

    2016-04-01

    Outer membrane vesicles (OMVs) play an important role in the pathogenicity of Gram-negative bacteria. Campylobacter jejuni produces OMVs that trigger IL-8, IL-6, hBD-3 and TNF-α responses from T84 intestinal epithelial cells and are cytotoxic to Caco-2 IECs and Galleria mellonella larvae. Proteomic analysis of 11168H OMVs identified the presence of three proteases, HtrA, Cj0511 and Cj1365c. In this study, 11168H OMVs were shown to possess proteolytic activity that was reduced by pretreatment with specific serine protease inhibitors. OMVs isolated from 11168H htrA, Cj0511 or Cj1365c mutants possess significantly reduced proteolytic activity. 11168H OMVs are able to cleave both E-cadherin and occludin, but this cleavage is reduced with OMVs pretreated with serine protease inhibitors and also with OMVs isolated from htrA or Cj1365c mutants. Co-incubation of T84 monolayers with 11168H OMVs results in a visible reduction in both E-cadherin and occludin. The addition of 11168H OMVs to the co-culture of live 11168H bacteria with T84 cells results in enhanced levels of bacterial adhesion and invasion in a time-dependent and dose-dependent manner. Further investigation of the cleavage of host cell structural proteins by C. jejuni OMVs should enhance our understanding of the interactions of this important pathogen with intestinal epithelial cells. © 2015 John Wiley & Sons Ltd.

  16. Expression of p27Kip1 and E-cadherin in Head and Neck Squamous Cell Carcinoma of Indonesian Patients.

    Science.gov (United States)

    E I, Auerkari; V, Joewono; D R, Handjari; A T, Sarwono; A W, Suhartono; K, Eto; M A, Ikeda

    2014-01-01

    Cancer cells exhibit characteristic damage of DNA and its expression. The expression of the tumor suppressors E-cadherin and p27(Kip1) has been tested on 57 head and neck squamous cell carcinomas (HNSCC) of Indonesian subjects. HNSCC tumor samples including both primary and (unrelated) nodal cases were obtained from the archives of Indonesian hospitals, in accordance with acknowledged ethical requirements. Only modest correlation was found between reduced expression of E-cadherin or p27(Kip1) with increased malignancy of primary and nodal growth. The observed strong correlation regardless of malignancy between the expressed levels of E-cadherin and p27(Kip1) suggests that also in combination these would not help to better predict the outcome of HNSCC.

  17. Igf1r signaling is indispensable for preimplantation development and is activated via a novel function of E-cadherin.

    Directory of Open Access Journals (Sweden)

    Ivan Bedzhov

    Full Text Available Insulin-like growth factor I receptor (Igf1r signaling controls proliferation, differentiation, growth, and cell survival in many tissues; and its deregulated activity is involved in tumorigenesis. Although important during fetal growth and postnatal life, a function for the Igf pathway during preimplantation development has not been described. We show that abrogating Igf1r signaling with specific inhibitors blocks trophectoderm formation and compromises embryo survival during murine blastocyst formation. In normal embryos total Igf1r is present throughout the membrane, whereas the activated form is found exclusively at cell contact sites, colocalizing with E-cadherin. Using genetic domain switching, we show a requirement for E-cadherin to maintain proper activation of Igf1r. Embryos expressing exclusively a cadherin chimera with N-cadherin extracellular and E-cadherin intracellular domains (NcEc fail to form a trophectoderm and cells die by apoptosis. In contrast, homozygous mutant embryos expressing a reverse-structured chimera (EcNc show trophectoderm survival and blastocoel cavitation, indicating a crucial and non-substitutable role of the E-cadherin ectodomain for these processes. Strikingly, blastocyst formation can be rescued in homozygous NcEc embryos by restoring Igf1r signaling, which enhances cell survival. Hence, perturbation of E-cadherin extracellular integrity, independent of its cell-adhesion function, blocked Igf1r signaling and induced cell death in the trophectoderm. Our results reveal an important and yet undiscovered function of Igf1r during preimplantation development mediated by a unique physical interaction between Igf1r and E-cadherin indispensable for proper receptor activation and anti-apoptotic signaling. We provide novel insights into how ligand-dependent Igf1r activity is additionally gated to sense developmental potential in utero and into a bifunctional role of adhesion molecules in contact formation and signaling.

  18. Expression of E-cadherin and involucrin in leukoplakia and oral cancer: an immunocytochemical and immunohistochemical study.

    Science.gov (United States)

    Silva, Alessandra Dutra da; Maraschin, Bruna Jalfim; Laureano, Natalia Koerich; Daroit, Natália; Brochier, Fernanda; Bündrich, Leonardo; Visioli, Fernanda; Rados, Pantelis Varvaki

    2017-03-06

    To assess the immunocytochemical and immunohistochemical correlation of adhesion (E-cadherin) and cell differentiation (involucrin) molecules in oral leukoplakia and oral squamous cell carcinoma. Cytological samples and biopsies were obtained from male and female patients aged over 30 years with oral leukoplakia (n = 30) and oral squamous cell carcinoma (n = 22). Cell scrapings and the biopsy were performed at the site of the lesion and histological slides were prepared for the immunocytochemical analysis of exfoliated oral mucosal cells and for the immunohistochemical analysis of biopsy tissues using E-cadherin and involucrin. Spearman's correlation and kappa coefficients were used to assess the correlation and level of agreement between the techniques. Immunostaining for E-cadherin and involucrin by both techniques was similar in the superficial layers of the histological sections compared with cell scrapings. However, there was no statistical correlation and agreement regarding the immunocytochemical and immunohistochemical expression of E-cadherin and involucrin in oral leukoplakia (R = 0.01, p = 0.958) (Kappa = 0.017, p = 0.92) or in oral squamous cell carcinoma (R = 0.26, p = 0.206) (Kappa = 0.36, p = 0.07). The immunoexpression of E-cadherin and involucrin in tissues is consistent with the expression patterns observed in exfoliated oral mucosal cells, despite the lack of a statistically significant correlation. There is an association of the histopathological characteristics of leukoplakia with the expression E-cadherin and of the microscopic aspects of oral squamous cell carcinoma with immunohistochemical expression of involucrin.

  19. Unique expression pattern of the EMT markers Snail, Twist and E-cadherin in benign and malignant parathyroid neoplasia.

    Science.gov (United States)

    Fendrich, Volker; Waldmann, Jens; Feldmann, Georg; Schlosser, Katja; König, Alexander; Ramaswamy, Annette; Bartsch, Detlef K; Karakas, Elias

    2009-04-01

    Epithelial and mesenchymal transitions (EMT) are essential for embryonic development and progression of non-invasive tumor cells into malignant, metastatic carcinomas. During embryogenesis, the parathyroid glands develop from pharyngeal pouches and migrate to their final destinations, densely enclosed by mesenchymal neural crest cells. In this study, we examined the expression of the EMT markers Snail, Twist and E-cadherin in normal parathyroid glands and benign and malignant parathyroid diseases. Using immunohistochemistry, we compared expression of E-cadherin, Snail and Twist in 25 patients with parathyroid adenoma, 25 patients with parathyroid hyperplasia, and nine patients with parathyroid cancer with normal parathyroid glands. Normal parathyroid glands, parathyroid adenomas, and parathyroid hyperplasias showed a typical membranous E-cadherin staining pattern. Expression of Snail was found in 22/25 parathyroid adenomas and in all parathyroid hyperplasias. Twist was expressed in 22/25 of parathyroid adenomas and in 20/25 parathyroid hyperplasias. Snail and Twist positive cells were homogeneously distributed throughout the gland. However, in all nine parathyroid carcinomas, membranous E-cadherin staining was lost. In addition, the expression pattern of Snail and Twist was changed and mostly limited to the invasive front of cancer tissue samples. Expression of Snail and Twist at the invasive front and consecutive loss of E-cadherin in parathyroid carcinomas suggests a key role of EMT in the tumorigenesis of this cancer. The unique expression pattern could help to distinguish between an adenoma and a non-metastatic carcinoma. Loss of E-cadherin and change of the expression pattern of Snail and Twist together should result in an en bloc resection or a close follow-up.

  20. Igf1r signaling is indispensable for preimplantation development and is activated via a novel function of E-cadherin.

    Directory of Open Access Journals (Sweden)

    Ivan Bedzhov

    Full Text Available Insulin-like growth factor I receptor (Igf1r signaling controls proliferation, differentiation, growth, and cell survival in many tissues; and its deregulated activity is involved in tumorigenesis. Although important during fetal growth and postnatal life, a function for the Igf pathway during preimplantation development has not been described. We show that abrogating Igf1r signaling with specific inhibitors blocks trophectoderm formation and compromises embryo survival during murine blastocyst formation. In normal embryos total Igf1r is present throughout the membrane, whereas the activated form is found exclusively at cell contact sites, colocalizing with E-cadherin. Using genetic domain switching, we show a requirement for E-cadherin to maintain proper activation of Igf1r. Embryos expressing exclusively a cadherin chimera with N-cadherin extracellular and E-cadherin intracellular domains (NcEc fail to form a trophectoderm and cells die by apoptosis. In contrast, homozygous mutant embryos expressing a reverse-structured chimera (EcNc show trophectoderm survival and blastocoel cavitation, indicating a crucial and non-substitutable role of the E-cadherin ectodomain for these processes. Strikingly, blastocyst formation can be rescued in homozygous NcEc embryos by restoring Igf1r signaling, which enhances cell survival. Hence, perturbation of E-cadherin extracellular integrity, independent of its cell-adhesion function, blocked Igf1r signaling and induced cell death in the trophectoderm. Our results reveal an important and yet undiscovered function of Igf1r during preimplantation development mediated by a unique physical interaction between Igf1r and E-cadherin indispensable for proper receptor activation and anti-apoptotic signaling. We provide novel insights into how ligand-dependent Igf1r activity is additionally gated to sense developmental potential in utero and into a bifunctional role of adhesion molecules in contact formation and signaling.

  1. The Different Expression Pattern of E-cadherin and β-catenin in Primary Nasopharyngeal Carcinoma and Its Metastases%上皮型钙粘素与β-链接素在鼻咽原发癌及其淋巴结转移中的表达差异

    Institute of Scientific and Technical Information of China (English)

    LI Zhi; 李智; LIN Suxia; 林素暇; LIANG Huizhen; 梁惠珍

    2004-01-01

    Objective: To detect the differences in the expression levels of protein and mRNA of E-cadherin and β-catenin in primary tumor and lymph node metastatic tumor of nasopharyngeal carcinoma (NPC),and to investigate the mechanism of invasion and metastasis of neoplastic cell in NPC. Methods: 21biopsies taken from primary tumor and another 21 biopsies from lymph node metastatic tumor of NPC were collected from the affiliated hospitals of Sun Yat-sen University of Medical Sciences during 1999-2002.Western blotting assay, immunohistochemical staining and reverse transcriptase-polymeraes chain reaction (RT-PCR) were adopted to detect the expression levels of protein and mRNA of E-cadherin and β-catenin in all of 42 samples. Results: (1) In 21 cases of lymph node metastatic tumor, the protein expression level of E-cadherin was lower detected by immunohistochemical staining (50% in average) and Western blotting (RI: 65±15.9 in average) than that in primary tumor of NPC (80% and 206.7±32.7 in average respectively). Furthermore, mRNA expression level of E-cadherin was also lower in metastatic tumor than that in primary tumor, with the difference being significant (P<0.05). (2) Both primary NPC and lymph node metastatic NPC were found to have high β-catenin protein and mRNA expression with the differences being not statistically significant (P>0.05). (3) There was no correlation between neoplastic cell expression ofβ-catenin and E-cadherin either in primary tumor or in lymph node metastatic tumors. Conclusion:Down-regulation of the expression of E-cadherin may play a critical role in neoplastic cell invasion and metastasis in NPC.

  2. Functional Assessment of αEβ7/E-cadherin Interactions in the Steady State Postnatal Thymus

    Directory of Open Access Journals (Sweden)

    Susan E. Prockop

    2004-01-01

    Full Text Available T cell differentiation in the thymus depends on sequential interactions between lymphoid progenitors and stromal cells in discrete regions of the cortex. Here, we show that despite αEβ7 expression by a subset of the earliest intrathymic precursors (and E-cadherin expression by thymic stroma, interaction of these elements is not required for proper localization of early progenitors into the cortex, or for successful steady state differentiation. These findings indicate that despite in vitro data demonstrating αEβ7 mediated adhesion and proliferation of intrathymic T cell precursor populations, T lymphocyte development can proceed independently of αEβ7/E-cadherin interactions.

  3. Cell junction proteins within the cochlea:A review of recent research

    Institute of Scientific and Technical Information of China (English)

    Bo Wang; Bohua Hu; Shiming Yang

    2015-01-01

    Cell—cell junctions in the cochlea are highly complex and well organized. The role of these junctions is to maintain structural and functional integrity of the cochlea. In this review, we describe classification of cell junction-associated proteins identified within the cochlea and provide a brief overview of the function of these proteins in adherent junctions, gap junctions and tight junctions. Copyright © 2016, PLA General Hospital Department of Otolaryngology Head and Neck Surgery. Production and hosting by Elsevier (Singapore) Pte Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

  4. miR-151a induces partial EMT by regulating E-cadherin in NSCLC cells

    DEFF Research Database (Denmark)

    Daugaard, Iben; Sanders, K J; Idica, A

    2017-01-01

    mortality. Here, we demonstrate that miR-151a is overexpressed in non-small cell lung cancer (NSCLC) patient specimens, as compared to healthy lung. In addition, miR-151a overexpression promotes proliferation, epithelial-to-mesenchymal transition (EMT) and induces tumor cell migration and invasion of NSCLC......-cadherin in miR-151a NSCLC cell lines potently repressed miR-151a-induced partial EMT and cell migration of NSCLC cells. In conclusion, our findings suggest that miR-151a functions as an oncomiR in NSCLC by targeting E-cadherin mRNA and inducing proliferation, migration and partial EMT....

  5. HYPERMETHYLATION STATUS OF E-CADHERIN AND p16INK4a IN GASTROINTESTINAL STROMAL TUMOR

    Institute of Scientific and Technical Information of China (English)

    LIANG Jian-fang

    2006-01-01

    Objective: To investigate the methylation status of CpG island in E-cadherin(CDH1), P16INK4a(P16)promoter region ,and to analyze their role in gastrointestinal stromal tumor (GISTs). Methods: A total of 56 surgically resected GISTs were obtained from January 2003 to December 2005. The routine H&E-stained sections and CD117, CD34-immunoreactions were reviewed to verify the morphologic diagnosis. Methylation status of the CDH1, P16INK4a promoter region was analyzed by methylation specific polymerase chain reaction (MSP) from chemically modified DNA after Na-bisulfite treatment. Results: The frequency of CDH1gene methylation was 32% (18 of 56) in GISTs. The rate was 9% (1 of 11), 21% (4 of 19), 41.6% (5 of 12), and 57% (8 of 14) for very low risk, low risk, intermediate risk, and high risk GISTs; P16INK4a methylation was found in 19 of 56(34%) cases. The rate was 0% (0 of 11), 16% (3 of 19), 50% (6 of 12), and 71% (10 of 14) for very low risk, low risk, intermediate risk, and high risk GISTs. Statistical analysis indicated that of the 56 cases, there was significant association of CDH1 and/or P16INK4a methylation status with tumor malignant behavior (methylation rate 23/56, 41%, P<0.01) and site (P<0.05). Conclusion: E-cadherin (CDH1) and/or P16INK4a promoter hypermethylation is strongly associated with risk grade, may be a useful biomarker for GISTs risk assessment, and may shed light on new therapeutic options to treat GISTs

  6. Chlamydia trachomatis Infection Is Associated with E-Cadherin Promoter Methylation, Downregulation of E-Cadherin Expression, and Increased Expression of Fibronectin and α-SMA—Implications for Epithelial-Mesenchymal Transition

    Directory of Open Access Journals (Sweden)

    Jovana Rajić

    2017-06-01

    Full Text Available Chlamydia trachomatis (Ct can induce scarring disease of the ocular mucosa, known as trachoma, the most common infectious cause of blindness worldwide. We hypothesized that epithelial-mesenchymal transition (EMT contributes to the fibrotic process in trachomatous scarring. Infection of human conjunctival epithelial cells (HCjE with Ct activated signaling pathways involved in EMT induction, which was correlated with decreased expression of E-cadherin, guardian of the epithelial phenotype. In addition, Ct infection was associated with increased expression of two mesenchymal cell markers: fibronectin and α-SMA. The DNA methylation statuses of selected regions of E-cadherin, fibronectin, and α-SMA genes revealed that Ct infection was accompanied with changes in DNA methylation of the E-cadherin promoter, while the expression of the two mesenchymal markers was not related with this epigenetic event. Our data suggest that Ct infection of conjunctival epithelial cells induces EMT-like changes that go along with modification of the methylation profile of the E-cadherin promoter and could, as one of the earliest events, contribute to processes triggering conjunctival scarring.

  7. Lateral junction dynamics lead the way out.

    Science.gov (United States)

    Behrndt, Martin; Heisenberg, Carl-Philipp

    2014-02-01

    Epithelial cell layers need to be tightly regulated to maintain their integrity and correct function. Cell integration into epithelial sheets is now shown to depend on the N-WASP-regulated stabilization of cortical F-actin, which generates distinct patterns of apical-lateral contractility at E-cadherin-based cell-cell junctions.

  8. Both the dimerization and immunochemical properties of E-cadherin EC1 domain depend on Trp(156) residue

    DEFF Research Database (Denmark)

    Laur, Oscar Y; Klingelhöfer, Jörg; Troyanovsky, Regina B;

    2002-01-01

    Using site-directed mutagenesis, we show in this paper that the adhesive interface detected in cadherin crystals is unlikely to mediate adhesive interaction between myc- and flag-tagged E-cadherin molecules in human A-431 cells. We also found that a critical residue within this interface, His(233...

  9. Differential expression of the epithelial mesenchymal transition factors Snail, Slug, Twist, TGF-β, and E-cadherin in ameloblastoma.

    Science.gov (United States)

    Kurioka, Kagami; Wato, Masahiro; Iseki, Tomio; Tanaka, Akio; Morita, Shosuke

    2017-06-01

    Epithelial mesenchymal transition (EMT), the transition of epithelial cells into motile mesenchymal cells, plays an important role in embryogenesis, cancer invasion, and metastasis. Ameloblastomas are common epithelial odontogenic tumors, occurring exclusively in the mandible with locally invasive growth. Thirty-seven ameloblastoma cases were evaluated for the involvement of EMT by immunohistochemical staining and western blotting using antibodies against Slug, Snail, Twist, TGF-β, and E-cadherin. Double immunostaining was also performed. Slug and TGF-β were expressed in the nuclei of peripheral and stellate reticulum cells of ameloblastoma nests. Twenty cases of Snail, 36 of Slug, 8 of Twist, and 19 of TGF-β showed strong expression in tumor cells in follicular and plexiform patterns. Expression of Slug and TGF-β increased in regions where the expression of E-cadherin was reduced. EMT was found to be associated with the local invasive growth of ameloblastoma. These data suggest that reduced expression of E-cadherin and over-expression of Slug, Snail, and TGF-β induce EMT. Given that ameloblastomas are characterized by local invasiveness, EMT might be related to their development. Thus, strong expression of Slug and TGF-β and reduced expression of E-cadherin might be related to the local invasiveness of ameloblastoma.

  10. New insights into the molecular mechanism of E-cadherin-mediated cell adhesion by free energy calculations

    DEFF Research Database (Denmark)

    Doro, Fabio; Saladino, Giorgio; Belvisi, Laura

    2015-01-01

    simulations, we reconstruct its conformational free energy landscape, obtaining the free energy profile connecting the inactive and active form. Our simulations predict that the E-cadherin monomer populates the open and closed forms almost equally, which is in agreement with the proposed "selected fit...

  11. Inverse correlation between CD8(+) inflammatory cells and E-cadherin expression in gallbladder cancer: Tissue microarray and imaging analysis.

    Science.gov (United States)

    Kai, Keita; Masuda, Masanori; Aishima, Shinichi

    2017-01-16

    To investigated the association between the tumor cells' expression of E-cadherin and the numbers of several types of inflammatory cells infiltrating into the invasive portion of gallbladder cancer (GBC). We analyzed 50 GBC cases for which a sufficient amount of tumor tissues for tissue microarray (TMA) had been saved. Three tissue cores (3.0 mm) of invasive lesion from each case were used for the TMA. The 4-μm cut sections on slides were immunostained using primary antibodies including E-cadherin for cancer cells, leukocyte common antigen for leukocyte, myeloperoxidase for neutrophils, CD3 for T cells, CD4 for helper T cells, CD8 for killer T cells, CD20 for B cells and CD68 for macrophages. The immunostained slides were digitally analyzed by imaging analysis software. A significant inverse correlation between the number of infiltrating CD8(+) cells at invasive areas and the expression of E-cadherin by cancer cells was observed (P = 0.0001), although the degree of this correlation was relatively weak (R = 0.32). The number of CD8(+) cells and the cancer cells' E-cadherin expression were also significantly correlated with tumor differentiation (well-differentiated vs poorly differentiated) (P = 0.0467 and P = 0.0294, respectively). Inverse correlation of T-stage and the number of CD8(+) cell infiltration was observed with statistical significance in comparison of T2 and T3 cases (P = 0.0324). Our findings indicate an inverse correlation of CD8(+) T cell infiltration and cancer cells' E-cadherin expression at invasive areas of GBC. Further analyses are essential to test these findings.

  12. Reversible Opening of Intercellular Junctions of Intestinal Epithelial and Brain Endothelial Cells With Tight Junction Modulator Peptides.

    Science.gov (United States)

    Bocsik, Alexandra; Walter, Fruzsina R; Gyebrovszki, Andrea; Fülöp, Lívia; Blasig, Ingolf; Dabrowski, Sebastian; Ötvös, Ferenc; Tóth, András; Rákhely, Gábor; Veszelka, Szilvia; Vastag, Monika; Szabó-Révész, Piroska; Deli, Mária A

    2016-02-01

    The intercellular junctions restrict the free passage of hydrophilic compounds through the paracellular clefts. Reversible opening of the tight junctions of biological barriers is investigated as one of the ways to increase drug delivery to the systemic circulation or the central nervous system. Six peptides, ADT-6, HAV-6, C-CPE, 7-mer (FDFWITP, PN-78), AT-1002, and PN-159, acting on different integral membrane and linker junctional proteins were tested on Caco-2 intestinal epithelial cell line and a coculture model of the blood-brain barrier. All peptides tested in nontoxic concentrations showed a reversible tight junctions modulating effect and were effective to open the paracellular pathway for the marker molecules fluorescein and albumin. The change in the structure of cell-cell junctions was verified by immunostaining for occludin, claudin-4,-5, ZO-1, β-catenin, and E-cadherin. Expression levels of occludin and claudins were measured in both models. We could demonstrate a selectivity of C-CPE, ADT-6, and HAV-6 peptides for epithelial cells and 7-mer and AT-1002 peptides for brain endothelial cells. PN-159 was the most effective modulator of junctional permeability in both models possibly acting via claudin-1 and -5. Our results indicate that these peptides can be effectively and selectively used as potential pharmaceutical excipients to improve drug delivery across biological barriers.

  13. Relation of glypican-3 and E-cadherin expressions to clinicopathological features and prognosis of mucinous and non-mucinous colorectal adenocarcinoma.

    Science.gov (United States)

    Foda, Abd Al-Rahman Mohammad; Mohammad, Mie Ali; Abdel-Aziz, Azza; El-Hawary, Amira Kamal

    2015-06-01

    Glypican-3 (GPC3) is a member of the membrane-bound heparin sulfate proteoglycans. E-cadherin is an adhesive receptor that is believed to act as a tumor suppressor gene. Many studies had investigated E-cadherin expressions in colorectal carcinoma (CRC) while only one study had investigated GPC3 expression in CRC. This study aims to investigate expression of GCP3 and E-cadherin in colorectal mucinous carcinoma (MA) and non-mucinous adenocarcinoma (NMA) using manual tissue microarray technique. Tumor tissue specimens are collected from 75 cases of MC and 75 cases of NMA who underwent radical surgery from Jan 2007 to Jan 2012 at the Gastroenterology Centre, Mansoura University, Egypt. Their clinicopathological parameters and survival data were revised and analyzed using established statistical methodologies. High-density manual tissue microarrays were constructed using modified mechanical pencil tip technique and immunohistochemistry for GPC3 and E-cadherin was done. NMA showed higher expression of GPC3 than MA with no statistically significant relation. NMA showed a significantly higher E-cadherin expression than MA. GPC3 and E-cadherin positivity rates were significantly interrelated in NMA, but not in MA, group. In NMA group, there was no significant relation between either GPC3 or E-cadherin expression and the clinicopathological features. In a univariate analysis, neither GPC3 nor E-cadherin expression showed a significant impact on disease-free survival (DFS) or overall survival (OS). GPC3 and E-cadherin expressions are not independent prognostic factors in CRC. However, expressions of both are significantly interrelated in NMA patients, suggesting an excellent interplay between both, in contrast to MA. Further molecular studies are needed to further explore the relationship between GCP3 and E-cadherin in colorectal carcinogenesis.

  14. E-cadherin and beta-catenin expression in Epstein-Barr virus-associated gastric carcinoma and their prognostic significance

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To examine the role of E-cadherin and betacatenin in carcinogenesis and to assess their prognostic implication in Epstein-Barr virus-associated gastric carcinomas (EBV-GCs).METHODS: We compared the frequency of E-cadherin and beta-catenin expression in 59 EBV-GCs and 120 non-EBV-GCs, and examined the association between patients' prognosis and the expressions of these proteins.RESULTS: Neither the cellular-membranous nor the cytoplasmic E-cadherin expression showed any difference between EBV-GCs and non-EBV-GCs. On the other hand, loss of membranous expression of betacatenin occurred more frequently in non-EBV-GCs than EBV-GCs [odds ratio = 0.41; 95% confidence interval (CI),0.19-0.90]. Furthermore, the nuclear and/or cytoplosmic expression of beta-catenin was seen more frequently in EBV-GCs than non-EBV-GCs (odds ratio = 2.23; 95% CI, 0.97-5.09), and was observed in a larger proportion of carcinoma cells of EBV-GCs than non-EBV-GCs (P = 0.024). Survival analysis for non-EBV-GC revealed that lymph node metastasis was significantly associated with poor prognosis (P < 0.001). Among EBVGCs, the depth of invasion (P = 0.005), lymph node metastasis (P = 0.004) and an intestinal type by Lauren classification (hazard ratio = 9.47; 95% CI, 2.67-33.6)were significantly associated with poor prognosis. On the other hand, nuclear and/or cytoplasmic expression of beta-catenin was associated with a better prognosis in patients with EBV-GC (hazard ratio = 0.32; 95% CI,0.11-0.93).CONCLUSION: We observed more frequent preservation of beta-catenin in cell membrane and accumulation in nuclei and/or cytoplasm in EBV-GCs than in non-EBV-GCs. Factors involved in the prognosis of EBV-GCs and non-EBV-GCs are different in the two conditions.

  15. Gap junction protein connexin43 exacerbates lung vascular permeability.

    Directory of Open Access Journals (Sweden)

    James J O'Donnell

    Full Text Available Increased vascular permeability causes pulmonary edema that impairs arterial oxygenation and thus contributes to morbidity and mortality associated with Acute Respiratory Distress Syndrome and sepsis. Although components of intercellular adhesive and tight junctions are critical for maintaining the endothelial barrier, there has been limited study of the roles of gap junctions and their component proteins (connexins. Since connexins can modulate inflammatory signaling in other systems, we hypothesized that connexins may also regulate pulmonary endothelial permeability. The relationships between connexins and the permeability response to inflammatory stimuli were studied in cultured human pulmonary endothelial cells. Prolonged treatment with thrombin, lipopolysaccharide, or pathological cyclic stretch increased levels of mRNA and protein for the major connexin, connexin43 (Cx43. Thrombin and lipopolysaccharide both increased intercellular communication assayed by transfer of microinjected Lucifer yellow. Although thrombin decreased transendothelial resistance in these cells, the response was attenuated by pretreatment with the connexin inhibitor carbenoxolone. Additionally, the decreases of transendothelial resistance produced by either thrombin or lipopolysaccharide were attenuated by reducing Cx43 expression by siRNA knockdown. Both carbenoxolone and Cx43 knockdown also abrogated thrombin-induced phosphorylation of myosin light chain. Taken together, these data suggest that increased lung vascular permeability induced by inflammatory conditions may be amplified via increased expression of Cx43 and intercellular communication among pulmonary endothelial cells.

  16. Thermostable direct hemolysin downregulates human colon carcinoma cell proliferation with the involvement of E-cadherin, and β-catenin/Tcf-4 signaling.

    Directory of Open Access Journals (Sweden)

    Pinki Chowdhury

    Full Text Available BACKGROUND: Colon cancers are the frequent causes of cancer mortality worldwide. Recently bacterial toxins have received marked attention as promising approaches in the treatment of colon cancer. Thermostable direct hemolysin (TDH secreted by Vibrio parahaemolyticus causes influx of extracellular calcium with the subsequent rise in intracellular calcium level in intestinal epithelial cells and it is known that calcium has antiproliferative activity against colon cancer. KEY RESULTS: In the present study it has been shown that TDH, a well-known traditional virulent factor inhibits proliferation of human colon carcinoma cells through the involvement of CaSR in its mechanism. TDH treatment does not induce DNA fragmentation, nor causes the release of lactate dehydrogenase. Therefore, apoptosis and cytotoxicity are not contributing to the TDH-mediated reduction of proliferation rate, and hence the reduction appears to be caused by decrease in cell proliferation. The elevation of E-cadherin, a cell adhesion molecule and suppression of β-catenin, a proto-oncogene have been observed in presence of CaSR agonists whereas reverse effect has been seen in presence of CaSR antagonist as well as si-RNA in TDH treated cells. TDH also triggers a significant reduction of Cyclin-D and cdk2, two important cell cycle regulatory proteins along with an up regulation of cell cycle inhibitory protein p27(Kip1 in presence of CaSR agonists. CONCLUSION: Therefore TDH can downregulate colonic carcinoma cell proliferation and involves CaSR in its mechanism of action. The downregulation occurs mainly through the involvement of E-cadherin-β-catenin mediated pathway and the inhibition of cell cycle regulators as well as upregulation of cell cycle inhibitors.

  17. A correlation between altered O-GlcNAcylation, migration and with changes in E-cadherin levels in ovarian cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Feng-zhen [Department of Obstetrics and Gynecology, The Second Affiliated Hospital of Chongqing Medical University, 76 Lin Jiang Road, Chongqing 400010, PR China. (China); Institute of Life Sciences, Chongqing Medical University, Chongqing 400016, PR China. (China); Yu, Chao; Zhao, De-zhang; Wu, Ming-jun [Institute of Life Sciences, Chongqing Medical University, Chongqing 400016, PR China. (China); Yang, Zhu, E-mail: cqyangz@vip.163.com [Department of Obstetrics and Gynecology, The Second Affiliated Hospital of Chongqing Medical University, 76 Lin Jiang Road, Chongqing 400010, PR China. (China); Institute of Life Sciences, Chongqing Medical University, Chongqing 400016, PR China. (China)

    2013-06-10

    O-GlcNAcylation is a dynamic and reversible posttranslational modification of nuclear and cytoplasmic proteins. In recent years, the roles of O-GlcNAcylation in several human malignant tumors have been investigated, and O-GlcNAcylation was found to be linked to cellular features relevant to metastasis. In this study, we modeled four diverse ovarian cancer cells and investigated the effects of O-GlcNAcylation on ovarian cancer cell migration. We found that total O-GlcNAcylation level was elevated in HO-8910PM cells compared to OVCAR3 cells. Additionally, through altering the total O-GlcNAcylation level by OGT silencing or OGA inhibition, we found that the migration of OVCAR3 cells was dramatically enhanced by PUGNAc and Thiamet G treatment, and the migration ability of HO-8910PM cells was significantly inhibited by OGT silencing. Furthermore, we also found that the expression of E-cadherin, an O-GlcNAcylated protein in ovarian cancer cells, was reduced by OGA inhibition in OVCAR3 cells and elevated by OGT silencing in HO-8910PM cells. These results indicate that O-GlcNAcylation could enhance ovarian cancer cell migration and decrease the expression of E-cadherin. Our studies also suggest that O-GlcNAcylation might become another potential target for the therapy of ovarian cancer. -- Highlights: • We examine the migration potential of diverse ovarian cancer cells. • We examine the total O-GlcNAcylation level of diverse ovarian cancer cells. • Increasing O-GlcNAcylation level will enhance the migration of ovarian cancer cells. • Reducing O-GlcNAcylation level will inhibit the migration of ovarian cancer cells. • The mechanism explains O-GlcNAcylation enhance ovarian cancer cell migration.

  18. Rad54 protein promotes branch migration of Holliday junctions.

    Science.gov (United States)

    Bugreev, Dmitry V; Mazina, Olga M; Mazin, Alexander V

    2006-08-03

    Homologous recombination has a crucial function in the repair of DNA double-strand breaks and in faithful chromosome segregation. The mechanism of homologous recombination involves the search for homology and invasion of the ends of a broken DNA molecule into homologous duplex DNA to form a cross-stranded structure, a Holliday junction (HJ). A HJ is able to undergo branch migration along DNA, generating increasing or decreasing lengths of heteroduplex. In both prokaryotes and eukaryotes, the physical evidence for HJs, the key intermediate in homologous recombination, was provided by electron microscopy. In bacteria there are specialized enzymes that promote branch migration of HJs. However, in eukaryotes the identity of homologous recombination branch-migration protein(s) has remained elusive. Here we show that Rad54, a Swi2/Snf2 protein, binds HJ-like structures with high specificity and promotes their bidirectional branch migration in an ATPase-dependent manner. The activity seemed to be conserved in human and yeast Rad54 orthologues. In vitro, Rad54 has been shown to stimulate DNA pairing of Rad51, a key homologous recombination protein. However, genetic data indicate that Rad54 protein might also act at later stages of homologous recombination, after Rad51 (ref. 13). Novel DNA branch-migration activity is fully consistent with this late homologous recombination function of Rad54 protein.

  19. Polycomb complex 2 is required for E-cadherin repression by the Snail1 transcription factor

    DEFF Research Database (Denmark)

    Herranz, Nicolás; Pasini, Diego; Díaz, Víctor M

    2008-01-01

    The transcriptional factor Snail1 is a repressor of E-cadherin gene (CDH1) expression essential for triggering epithelial-mesenchymal transition (EMT). Snail1 represses CDH1 directly binding its promoter and inducing the synthesis of Zeb1 repressor. In this article we show that repression of CDH1...... by Snail1, but not by Zeb1, is dependent on the activity of the Polycomb repressive complex 2 (PRC2). ES cells null for Suz12, one of the components of PRC2, show higher levels of Cdh1 mRNA than control ES cells. In tumour cells, interference of PRC2 activity prevents the ability of Snail1 to down......-regulate CDH1 and partially de-represses CDH1. Chromatin immunoprecipitation assays demonstrated that Snail1 increases the binding of Suz12 to CDH1 promoter and the tri-methylation of lysine 27 in the histone 3. Moreover, Snail1 interacts with Suz12 and Ezh2 as shown by coimmunoprecipitation experiments...

  20. E-CADHERIN AND CD44V6 EXPRESION IN HUMAN HEPATOCELLULAR CARCINOMAS

    Institute of Scientific and Technical Information of China (English)

    郑建明; 郑唯强; 龚志锦; 朱明华; 戴益民; 张照环

    2001-01-01

    To investigate the significance of E- cadherin (E-cad) and CD44v6 expression in human hepatocellular carcinomas (HCCs). Methods: An immunohistochemical method was used to detect E-cad and CD44v6 expression in 66 cases of HCCs. Results: The positive rates of E-cad and CD44v6 expression in human HCCs were 42.4%(28/66) and 39.4%(26/66), respectively. There was an inverse correlation between E-cad expression and invasive and metastatic potential of HCCs (P<0.01), and a positive correlation between the CD44v6 expression and invasive and metastatic potential of HCCs (P<0.01). Moreover, the 5-year survival rate in the E-cad-positive group was higher than in E-cad-negative group (P<0.01), and that in the CD44v6-positive group was lower than in the CD44v6-negative expression group (P<0.05). Conclusion: these data show a possible association between E-cad and CD44v6 expression and the potential of invasion and metastasis in HCCs. E-cad and CD44v6 expression may be used as an auxiliary prognostic indicator in HCCs.

  1. Hypermethylation Status of E-Cadherin Gene in Gastric Cancer Patients in a High Incidence Area.

    Science.gov (United States)

    Rashid, Haroon; Alam, Khursheed; Afroze, Dil; Yousuf, Adfar; Banday, Manzoor; Kawoosa, Fizalah

    2016-01-01

    Gastric cancer (GC) is the fourth most prevalant cancer and the second leading cause of cancer-related mortality worldwide. As in other cancers gastric carcinogenesis is multifactorial involving environmental, genetic and epigenetic components. Epigenetic silencing due to hypermethylation of tumour suppressor genes is one of the key events in gastric carcinogenesis. This study was aimed to analyse the hypermethylation status of the E-Cadherin (CDH1) gene promoter in GCs in the ethnic Kashmiri population. In this study a total of 80 GC patients were recruited. Hypermethylation in tumour tissue was detected by methylation specific PCR (MS-PCR). Hypermethylation of CDH1 promoter was observed in 52 (65%) of gastric carcinoma cases which was significantly much higher than adjacent normal tissue [p≤0.0001]. Further the frequency of CDH1 promoter methylation was significantly different with intestinal and diffuse types of gastric cancer [55.7% vs 82.1%; CDH1 hypermethylation [P≤0.05]. Thus the current data indicate a vital role of epigenetic alteration of CDH1 in the causation and development of gastric cancer, particularly of diffuse type, in our population.

  2. Altered E-Cadherin Levels and Distribution in Melanocytes Precede Clinical Manifestations of Vitiligo.

    Science.gov (United States)

    Wagner, Roselyne Y; Luciani, Flavie; Cario-André, Muriel; Rubod, Alain; Petit, Valérie; Benzekri, Laila; Ezzedine, Khaled; Lepreux, Sébastien; Steingrimsson, Eirikur; Taieb, A; Gauthier, Yvon; Larue, Lionel; Delmas, Véronique

    2015-07-01

    Vitiligo is the most common depigmenting disorder resulting from the loss of melanocytes from the basal epidermal layer. The pathogenesis of the disease is likely multifactorial and involves autoimmune causes, as well as oxidative and mechanical stress. It is important to identify early events in vitiligo to clarify pathogenesis, improve diagnosis, and inform therapy. Here, we show that E-cadherin (Ecad), which mediates the adhesion between melanocytes and keratinocytes in the epidermis, is absent from or discontinuously distributed across melanocyte membranes of vitiligo patients long before clinical lesions appear. This abnormality is associated with the detachment of the melanocytes from the basal to the suprabasal layers in the epidermis. Using human epidermal reconstructed skin and mouse models with normal or defective Ecad expression in melanocytes, we demonstrated that Ecad is required for melanocyte adhesiveness to the basal layer under oxidative and mechanical stress, establishing a link between silent/preclinical, cell-autonomous defects in vitiligo melanocytes and known environmental stressors accelerating disease expression. Our results implicate a primary predisposing skin defect affecting melanocyte adhesiveness that, under stress conditions, leads to disappearance of melanocytes and clinical vitiligo. Melanocyte adhesiveness is thus a potential target for therapy aiming at disease stabilization.

  3. E-cadherin and beta-catenin expression in breast medullary carcinomas.

    Science.gov (United States)

    Charpin, C; Bonnier, P; Garcia, S; Andrac, L; Crebassa, B; Dorel, M; Lavaut, M N; Allasia, C

    1999-08-01

    The initial step of cancer invasion and metastasis is the escape of tumour cells from the primary site, involving disruption of normal cell-cell adhesion and E-cadherin (E-cad) and beta-catenin (beta-cat) down-regulation, as shown in various types of human malignancies including breast carcinomas. Medullary carcinomas are high grade and poorly differentiated tumours with syncytial typical pattern, and prognosis unexpectedly better than that in high grade breast carcinomas. In a series of 55 breast typical medullary carcinomas diagnosed according to the strict use of Ridolfi et al (Cancer 40: 1365-1385, 1977) criteria, E-cad and beta-cat were investigated using quantitative (SAMBA 2005 system) immunocytochemical assays on frozen sections. Results were compared to that obtained on paraffin sections and in a series (n=55) of grade 3 ductal carcinomas. It was shown that medullary carcinomas significantly (p<0.001) expressed more E-cad and beta-cat than grade 3 ductal carcinomas. E-cad and beta-cat correlated with high expression of P53, of c-erbB, and of Ki-67 antigens, and with lack of hormone receptors antigenic sites (p<0.001). It was concluded that favourable prognosis and syncytial pattern of typical breast medullary carcinomas likely results, at least partly, from a particular expression of cell-cell adhesion molecules, significantly limiting tumour growth and efficiently mastering the tumour cell dissemination, opposing to high proliferative activity (grade 3).

  4. Dithiolethione modified valproate and diclofenac increase E-cadherin expression and decrease proliferation of non-small cell lung cancer cells

    Science.gov (United States)

    Moody, Terry W.; Switzer, Christopher; Santana-Flores, Wilmarie; Ridnour, Lisa A.; Berna, Marc; Thill, Michelle; Jensen, Robert T.; Sparatore, Anna; Del Soldato, Piero; Yeh, Grace C; Roberts, David D.; Giaccone, Giuseppe; Wink, David A.

    2009-01-01

    The effects of dithiolethione-modified valproate, diclofenac and sulindac on non-small cell lung cancer (NSCLC) cells were investigated. Sulfur(S)-valproate and S-diclofenac at 1 μg/ml concentrations significantly reduced prostaglandin (PG)E2 levels in NSCLC cell lines A549 and NCI-H1299 as did the COX-2 inhibitor DuP-697. In vitro, S-valproate, S-diclofenac and S-sulindac half-maximally inhibited the clonal growth of NCI-H1299 cells at 6, 6 and 15 μg/ml, respectively. Using the MTT assay, 10 μg/ml S-valproate, NO-aspirin and Cay10404, a selective COX-2 inhibitor, but not SC-560, a selective COX-1 inhibitor, inhibited the growth of A549 cells. In vivo, 18 mg/kg i.p. of S-valproate and S-diclofenac, but not S-sulindac, significantly inhibited A549 or NCI-H1299 xenograft proliferation in nude mice, but had no effect on the nude mouse body weight. The mechanism by which S-valproate and S-diclofenac inhibited the growth of NSCLC cells was investigated. Nitric oxide-aspirin but not S-valproate caused apoptosis of NSCLC cells. By Western blot, S-valproate and S-diclofenac increased E-cadherin but reduced vimentin and ZEB1 (a transcriptional suppressor of E-cadherin) protein expression in NSCLC cells. Because S-valproate and S-diclofenac inhibit the growth of NSCLC cells and reduce PGE2 levels, they may prove beneficial in the chemoprevention and/or therapy of NSCLC, PMID:19628293

  5. Involvement of PPAR gamma and E-cadherin/beta-catenin pathway in the antiproliferative effect of conjugated linoleic acid in MCF-7 cells.

    Science.gov (United States)

    Bocca, Claudia; Bozzo, Francesca; Francica, Simona; Colombatto, Sebastiano; Miglietta, Antonella

    2007-07-15

    Conjugated linoleic acid (CLA) is a naturally occurring fatty acid, which has been shown to exert beneficial effects against breast carcinogenesis. It has been reported that CLA could modulate cellular proliferation and differentiation through the activation of peroxisome proliferator-activated receptors (PPARs). Among different PPAR isotypes, PPAR gamma is involved in growth inhibition of transformed cells. Ligands of PPAR gamma are considered as potential anticancer drugs, so CLA was tested for its ability to induce PPAR gamma expression in MCF-7 breast cancer cells. The effects of CLA and of a specific synthetic PPAR gamma antagonist were evaluated on cell growth as well as on parameters responsible for cell growth regulation. We demonstrated here that CLA stimulated the expression of PPAR gamma to levels up to control and caused PPAR gamma translocation into the nucleus. Furthermore, the overexpression of PPAR gamma positively correlates with the inhibition of cell proliferation and with the modulation of ERK signaling induced by CLA; in all cases the administration of the antagonist reverted CLA effects. The PPAR-signaling pathway is connected with the beta-catenin/E-cadherin pathway, thus we evaluated CLA effects on the expression and cellular distribution of these proteins, which are involved in cell adhesion and responsible for invasive behavior. The treatment with CLA determined the up-regulation and the redistribution of beta-catenin and E-cadherin and the antagonist reverted only the effect on beta-catenin. These studies indicate that CLA regulates PPAR gamma expression by selectively acting as an agonist and may influence cell-cell adhesion and invasiveness of MCF-7 cells. (c) 2007 Wiley-Liss, Inc.

  6. Gap junction proteins are key drivers of endocrine function.

    Science.gov (United States)

    Meda, Paolo

    2017-03-08

    It has long been known that the main secretory cells of exocrine and endocrine glands are connected by gap junctions, made by a variety of connexin species that ensure their electrical and metabolic coupling. Experiments in culture systems and animal models have since provided increasing evidence that connexin signaling contributes to control the biosynthesis and release of secretory products, as well as to the life and death of secretory cells. More recently, genetic studies have further provided the first lines of evidence that connexins also control the function of human glands, which are central to the pathogenesis of major endocrine diseases. Here, we summarize the recent information gathered on connexin signaling in these systems, since the last reviews on the topic, with particular regard to the pancreatic beta cells which produce insulin, and the renal cells which produce renin. These cells are keys to the development of various forms of diabetes and hypertension, respectively, and combine to account for the exploding, worldwide prevalence of the metabolic syndrome. This article is part of a Special Issue entitled: Gap Junction Proteins edited by Jean Claude Herve. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Down-regulated E-cadherin expression is associated with poor five-year overall survival in bone and soft tissue sarcoma: results of a meta-analysis.

    Directory of Open Access Journals (Sweden)

    Ning Wang

    Full Text Available To conduct a meta-analysis to evaluate the prognostic role of E-cadherin expression in bone and soft tissue sarcomas.The PubMed, EMBASE, and Web of Science databases were searched using terms related to E-cadherin, sarcoma, and prognosis for all articles published in English before March 2014. Pooled effect was calculated from the available data to evaluate the association between negative E-cadherin expression and 5-year overall survival and tumor clinicopathological features in sarcoma patients. Pooled odds ratios (OR and risk ratios (RR with 95% confidence intervals (CI were calculated using a fixed-effects model.Eight studies met the selection criteria and reported on 812 subjects. A total of 496 subjects showed positive E-cadherin expression (59.9%. Negative E-cadherin expression in bone and soft tissue sarcomas was correlated with lower 5-year overall survival (OR = 3.831; 95% CI: 2.246-6.534, and was associated with higher clinical stage (RR = 1.446; 95% CI: 1.030-2.028 and with male sex (RR = 0.678; 95% CI: 0.493-0.933.In the E-cadherin negative group, 5-year overall survival was significantly worse than in the E-cadherin positive group. However, further studies are required to confirm these results.

  8. Removal of sialic acid from the surface of human MCF-7 mammary cancer cells abolishes E-cadherin-dependent cell-cell adhesion in an aggregation assay.

    Science.gov (United States)

    Deman, J J; Van Larebeke, N A; Bruyneel, E A; Bracke, M E; Vermeulen, S J; Vennekens, K M; Mareel, M M

    1995-09-01

    MCF-7 human breast cancer cells express E-cadherin and show, at least in some circumstances, E-cadherin-dependent cell-cell adhesion (Bracke et al., 1993). The MCF-7/AZ variant spontaneously displays E-cadherin-dependent fast aggregation; in the MCF-7/6 variant, E-cadherin appeared not to be spontaneously functional in the conditions of the fast aggregation assay, but function could be induced by incubation of the suspended cells in the presence of insulinlike growth factor I (IGF-I) (Bracke et al., 1993). E-cadherin from MCF-7 cells was shown to contain sialic acid. Treatment with neuraminidase was shown to remove this sialic acid, as well as most of the sialic acid present at the cell surface. Applied to MCF-7/AZ, and MCF-7/6 cells, pretreatment with neuraminidase abolished spontaneous as well as IGF-I induced, E-cadherin-dependent fast cell-cell adhesion of cells in suspension, as measured in the fast aggregation assay. Treatment with neuraminidase did not, however, inhibit the possibly different, but equally E-cadherin-mediated, process of cell-cell adhesion of MCF-7 cells on a flat plastic substrate as assessed by determining the percentage of cells remaining isolated (without contact with other cells) 24 h after plating.

  9. Clinico-pathological correlation of E-cadherin expression at the invasive tumor front of Indian oral squamous cell carcinomas: An immunohistochemical study

    Science.gov (United States)

    Mehendiratta, Monica; Solomon, Monica Charlotte; Boaz, Karen; Guddattu, Vasudeva; Mohindra, Aashima

    2014-01-01

    Background: Recent studies have indicated that although malignant cells at the invasive tumor front, bare morphological resemblance to the cells at central portion of the tumor, their molecular character differs significantly. E-cadherin is a cell-cell adhesion molecule that connects epithelial cells. This study attempts to correlate the E-cadherin expression at the invasive tumor front with tumor differentiation along with its clinico-pathological parameters. Materials and Methods: Immunohistochemical staining with E-cadherin was carried out on archival cases of primary oral squamous cell carcinomas (n = 30). The E-cadherin expression at the invasive tumor front was analyzed and was linked to clinico-pathological parameters including patient prognosis. Results: The downregulation of E-cadherin expression at the invasive tumor edge when compared with patient's prognosis yielded a significant correlation (P = 0.041) but its correlation with the degree of differentiation determined was not significant (P = 0.27). Also, its association with tumor size and lymph node status was negative. Conclusions: Loss of E-cadherin expression at the invasive tumor front is an important event in the progression of oral squamous cell carcinomas. Tumors with a loss of expression of E-cadherin are those which had a poor prognosis PMID:25328302

  10. Gap junction proteins in the light-damaged albino rat.

    Science.gov (United States)

    Guo, Cindy X; Tran, Henry; Green, Colin R; Danesh-Meyer, Helen V; Acosta, Monica L

    2014-01-01

    Changes in connexin expression are associated with many pathological conditions seen in animal models and in humans. We hypothesized that gap junctions are important mediators in tissue dysfunction and injury processes in the retina, and therefore, we investigated the pattern of connexin protein expression in the light-damaged albino rat eye. Adult Sprague-Dawley rats were exposed to intense light for 24 h. The animals were euthanized, and ocular tissue was harvested at 0 h, 6 h, 24 h, 48 h, and 7 days after light damage. The tissues were processed for immunohistochemistry and western blotting to analyze the expression of the gap junction proteins in the light-damaged condition compared to the non-light-damaged condition. Cell death was detected using the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) technique. Intense light exposure caused increased TUNEL labeling of photoreceptor cells. Immunocytochemistry revealed that connexin 36 (Cx36) was significantly increased in the inner plexiform layer and Cx45 was significantly decreased in the light-damaged retina. The pattern of Cx36 and Cx45 labeling returned to normal 7 days after light damage. Cx43 significantly increased in the RPE and the choroid in the light-damaged tissue, and decreased but not significantly in the retina. This elevated Cx43 expression in the choroid colocalized with markers of nitration-related oxidative stress (nitrotyrosine) and inflammation (CD45 and ionized calcium-binding adaptor molecule-1) in the choroid. The results suggest that connexins are regulated differently in the retina than in the choroid in response to photoreceptor damage. Changes in connexins, including Cx36, Cx43, and Cx45, may contribute to the damage process. Specifically, Cx43 was associated with inflammatory damage. Therefore, connexins may be candidate targets for treatment for ameliorating disease progression.

  11. Interactions between E-Cadherin and MicroRNA Deregulation in Head and Neck Cancers: The Potential Interplay

    OpenAIRE

    2014-01-01

    E-cadherin expression in the head and neck epithelium is essential for the morphogenesis and homeostasis of epithelial tissues. The cadherin-mediated cell-cell contacts are required for the anchorage-dependent growth of epithelial cells. Further, survival and proliferation require physical tethering created by proper cell-cell adhesion. Otherwise, the squamous epithelial cells will undergo programmed cell death. Head and neck cancers can escape from anoikis and enter into the epithelial-mesen...

  12. Presence and distribution of E-cadherin in the 4-cell golden hamster embryo. Effect of maternal age and parity.

    Science.gov (United States)

    Trejo, A; Ambriz, D; Navarro-Maldonado, M C; Mercado, E; Rosado, A

    2008-08-01

    Maternal age dependency of gestation time in hamster and in other mammals is a well demonstrated fact. We have recently shown that adult nulliparous and multiparous hamster females show significant asynchrony and retard on early embryo development (from two blastomeres to morula stages) when compared with nulliparous young females. The number of cell-cell adhesions between blastomeres in early embryo development has been reported to be a good indication of the ability of embryos to cleave and develop. In this work we studied, by indirect immunofluorescence, the presence and distribution of E-cadherin in 4-cell embryos obtained from nulliparous young (NYF), nulliparous adult (NAF) and multiparous adult (MAF) hamster females. Distribution and intensity of fluorescence was observed and registered using confocal microscopy. Staining intensities for E-cadherin were quantified by computed densitometry in the free membrane regions, in the cytoplasm region and in the cell-cell adhesion zones of each embryo. E-Cadherin in all the studied zones was significantly higher (p<0.01) in NYF. Cadherin concentration in the intercellular membranes was always statistically higher (p<0.05) than in the free membrane regions. An appreciable concentration of E-cadherin was found in the cytoplasm of the 4-cell embryos obtained from the three groups of females, but was significantly higher in NYF. No statistical differences were observed in any of the parameters studied between NAF and MAF. Our results seem to indicate that changes in the reproductive behavior related to age and/or multiparity may be correlated with changes in the processes related to intercellular adhesions during early cleavage.

  13. Cell adhesion and sorting in embryoid bodies derived from N- or E-cadherin deficient murine embryonic stem cells

    Directory of Open Access Journals (Sweden)

    Robert Moore

    2014-01-01

    The primitive endoderm epithelial structure in mouse blastocysts forms following cell differentiation and subsequent sorting, and this two-step process can be reproduced in vitro using an embryoid body model. We found that in the chimeric embryoid bodies consisting of paired wildtype and E-cadherin null ES cells, the wildtype sorted to the center and were enveloped by the less adhesive E-cadherin null cells, in accord with Steinberg's hypothesis. However, wildtype and N-cadherin null ES cells intermixed and did not segregate, a situation that may be explained by Albert Harris' modified principle, which incorporates the unique properties of living cells. Furthermore, in chimeric embryoid bodies composed of N-cadherin and E-cadherin null ES cells, the two weakly interacting cell types segregated but did not envelop one another. Lastly, the most consistent and striking observation was that differentiated cells sorted to the surface and formed an enveloping layer, regardless of the relative cell adhesive affinity of any cell combination, supporting the hypothesis that the ability of the differentiated cells to establish apical polarity is the determining factor in surface sorting and positioning.

  14. Abrogation of E-cadherin-mediated cellular aggregation allows proliferation of pluripotent mouse embryonic stem cells in shake flask bioreactors.

    Directory of Open Access Journals (Sweden)

    Lisa Mohamet

    Full Text Available BACKGROUND: A fundamental requirement for the exploitation of embryonic stem (ES cells in regenerative medicine is the ability to reproducibly derive sufficient numbers of cells of a consistent quality in a cost-effective manner. However, undifferentiated ES cells are not ideally suited to suspension culture due to the formation of cellular aggregates, ultimately limiting scalability. Significant advances have been made in recent years in the culture of ES cells, including automated adherent culture and suspension microcarrier or embryoid body bioreactor culture. However, each of these methods exhibits specific disadvantages, such as high cost, additional downstream processes or reduced cell doubling times. METHODOLOGY/PRINCIPAL FINDINGS: Here we show that abrogation of the cell surface protein E-cadherin, using either gene knockout (Ecad-/- or the neutralising antibody DECMA-1 (EcadAb, allows culture of mouse ES cells as a near-single cell suspension in scalable shake flask culture over prolonged periods without additional media supplements. Both Ecad-/- and EcadAb ES cells exhibited adaptation phases in suspension culture, with optimal doubling times of 7.3 h±0.9 and 15.6 h±4.7 respectively and mean-fold increase in viable cell number of 95.1±2.0 and 16±0.9-fold over 48 h. EcadAb ES cells propagated as a dispersed cell suspension for 15 d maintained expression of pluripotent markers, exhibited a normal karyotype and high viability. Subsequent differentiation of EcadAb ES cells resulted in expression of transcripts and proteins associated with the three primary germ layers. CONCLUSIONS/SIGNIFICANCE: This is the first demonstration of the culture of pluripotent ES cells as a near-single cell suspension in a manual fed-batch shake flask bioreactor and represents a significant improvement on current ES cell culture techniques. Whilst this proof-of-principle method would be useful for the culture of human ES and iPS cells, further steps are

  15. E-cadherin expression and prognosis of head and neck squamous cell carcinoma: evidence from 19 published investigations

    Directory of Open Access Journals (Sweden)

    Ren X

    2016-04-01

    Full Text Available Xusheng Ren,1,2 Jianning Wang,2 Xuefen Lin,1,3 Xuxia Wang1,3 1Department of Oral and Maxillofacial Surgery, Stomatological Hospital of Shandong University, 2Department of Oral and Maxillofacial Surgery, Jinan Stomatological Hospital, 3Shandong Province Key Laboratory of Oral Tissue Regeneration, Stomatological Hospital of Shandong University, Jinan, Shandong Province, People’s Republic of China Objective: The objective of this study was to review the published literature and investigate whether E-cadherin gene is a prognostic factor in head and neck squamous cell carcinoma by conducting a meta-analysis.Methods: Studies were identified from the databases Embase, Medline, and Cochrane Library by using the keywords “E-cadherin gene” and “head and neck cancer”. Overall survival (OS and disease-free survival (DFS were the primary outcome measurements.Results: Our literature review identified 1,458 articles; 19 studies with a total number of 2,012 cases were eligible for inclusion in the meta-analysis. The hazard ratio (HR for OS of patients with decreased expression of E-cadherin gene was 0.57 (95% CI =0.37, 0.89; P=0.000. However, statistical heterogeneity was unacceptably high (I2=74.5%, P=0.000. After sensitivity analysis, heterogeneity became acceptable, and the effect measure was still significant (I2=7.0%; HR =0.52; 95% CI =0.40, 0.66; P=0.000. The HR for DFS was 0.53 (95% CI =0.42, 0.67; P=0.000.Conclusion: This meta-analysis showed clear evidence that high E-cadherin gene expression is a positive prognostic factor of head and neck squamous cell carcinoma, resulting in better OS and DFS. However, this conclusion must be interpreted with caution due to a few limitations. Keywords: E-cadherin gene, prognosis, head and neck squamous cell carcinoma, immunohistochemistry 

  16. Transition of Immunohistochemical Expression of E-Cadherin and Vimentin from Premalignant to Malignant Lesions of Oral Cavity and Oropharynx

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    Kafil Akhtar

    2016-05-01

    Full Text Available Objectives: We sought to study the expression of epithelial-to-mesenchymal transition markers E-cadherin and vimentin in precancerous lesions of the oral cavity and oropharynx and to use the specific pattern of expression to predict invasiveness. Methods: This cross-sectional study looked at 87 cases of oral and oropharyngeal lesions obtained between December 2012 and November 2014 in the Department of Pathology, Jawaharlal Nehru Medical College, Aligarh Muslim University, India. Fifty-three biopsies from the buccal mucosa, tongue, and pharynx and 34 resected oral specimens were evaluated for premalignant and malignant lesions using hematoxylin and eosin and immunohistochemical stains. Immunohistochemical expression of epithelial marker E-cadherin and mesenchymal marker vimentin was evaluated wherever possible. Slides were examined for staining pattern (cytoplasmic or membrane, proportion, and intensity of staining of tumor cells. Patients follow-up and therapy related changes were also studied. Results: There were 64 premalignant and 23 malignant cases in our study with 65 (74.7% cases seen in males and 22 (25.3% cases seen in females. The majority of malignant cases, (n = 15; 64.2% were seen in the fifth and sixth decades of life while most of the premalignant lesions (n = 36; 56.4% were seen in the fourth and fifth decade. Amongst the 64 premalignant oral lesions, leukoplakia comprised of 14 cases (21.9%, of which three cases had associated mild to moderate dysplasia. The majority of premalignant lesions showed strong E-cadherin expression and decreased expression of vimentin with negative and weak expression in both dysplasias and carcinoma in situ (p = 0.013. E-cadherin expression was significantly reduced in invasive carcinomas compared to dysplasias and carcinoma in situ and the difference in immunoreactivity was statistically significant (p < 0.050. Vimentin expression increased as the tumor progressed from dysplasias to carcinoma in

  17. Intestinal epithelial barrier function and tight junction proteins with heat and exercise

    DEFF Research Database (Denmark)

    Dokladny, Karol; Zuhl, Micah N; Moseley, Pope L

    2016-01-01

    (passive hyperthermia) heat stress on tight junction barrier function in in vitro and in vivo (animals and humans) models. Our secondary focus is to review changes in tight junction proteins in response to exercise or hyperthermic conditions. Finally, we discuss some pharmacological or nutritional...... interventions that may affect the cellular mechanisms involved in maintaining homeostasis of the intestinal epithelial tight junction barrier during heat stress or exercise....

  18. E-cadherin downregulation at the infiltrating tumour front is associated with histological grade and stage in colorectal carcinoma of Malaysians.

    Science.gov (United States)

    Dass, Serena Diane; Cheah, Phaik-Leng; Ong, Diana Bee-Lan; Teoh, Kean-Hooi; Looi, Lai-Meng

    2015-04-01

    Loss of E-cadherin, a 120 kDA transmembrane glycoprotein responsible for cell-cell adhesion, is one of the hallmarks of epithelial-mesenchymal-transition (EMT). E-cadherin expression was immunohistochemically studied in 94 histopathologically re-confirmed colorectal carcinomas (CRC) using a monoclonal antibody to E-cadherin (Dako: Clone NCH-38) on a Ventana Benchmark XT automated system. Each case was assessed for E-cadherin immunopositivity at two separate locations viz the tumour centre (TC) as well as the infiltrating front (IF). Expression was semiquantitated for proportion of immunopositive malignant cells as 0 (negative), 1 (1-25% staining), 2 (26-50% staining), 3 (51-75% staining) and 4 (>75% staining) and staining intensity: 0 (negative), 1 (weak), 2 (moderate) and 3 (strong). The final histoscore of E-cadherin immunopositivity was arbitrarily computed as proportion of immunopositivity multiplied by staining intensity of the malignant cells. E-cadherin histoscores were significantly lower at the IF (4.5±2.5) compared with TC (10.7±2.4). Furthermore, the histoscores were significantly reduced at the IF of 49 TNM III+IV tumours (3.6±2.5) compared with 45 II+III CRC (5.4±2.2). Reduction of E-cadherin expression was also noted in the 23 high grade (TC=8.6±3.2; IF=2.6±2.3) compared with 71 low grade tumours (TC=11.4±1.5; IF=5.1±2.3). E-cadherin is downregulated at the infiltrating front of CRC, possibly marking for EMT at this location. The downregulation is further enhanced amongst late stage and high grade tumours compared with earlier stage and low grade tumours; findings which are similar to that noted in CRC of other populations.

  19. Wingless signalling alters the levels, subcellular distribution and dynamics of Armadillo and E-cadherin in third instar larval wing imaginal discs.

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    Ildiko M L Somorjai

    Full Text Available BACKGROUND: Armadillo, the Drosophila orthologue of vertebrate ss-catenin, plays a dual role as the key effector of Wingless/Wnt1 signalling, and as a bridge between E-Cadherin and the actin cytoskeleton. In the absence of ligand, Armadillo is phosphorylated and targeted to the proteasome. Upon binding of Wg to its receptors, the "degradation complex" is inhibited; Armadillo is stabilised and enters the nucleus to transcribe targets. METHODOLOGY/PRINCIPAL FINDINGS: Although the relationship between signalling and adhesion has been extensively studied, few in vivo data exist concerning how the "transcriptional" and "adhesive" pools of Armadillo are regulated to orchestrate development. We have therefore addressed how the subcellular distribution of Armadillo and its association with E-Cadherin change in larval wing imaginal discs, under wild type conditions and upon signalling. Using confocal microscopy, we show that Armadillo and E-Cadherin are spatio-temporally regulated during development, and that a punctate species becomes concentrated in a subapical compartment in response to Wingless. In order to further dissect this phenomenon, we overexpressed Armadillo mutants exhibiting different levels of activity and stability, but retaining E-Cadherin binding. Arm(S10 displaces endogenous Armadillo from the AJ and the basolateral membrane, while leaving E-Cadherin relatively undisturbed. Surprisingly, DeltaNArm(1-155 caused displacement of both Armadillo and E-Cadherin, results supported by our novel method of quantification. However, only membrane-targeted Myr-DeltaNArm(1-155 produced comparable nuclear accumulation of Armadillo and signalling to Arm(S10. These experiments also highlighted a row of cells at the A/P boundary depleted of E-Cadherin at the AJ, but containing actin. CONCLUSIONS/SIGNIFICANCE: Taken together, our results provide in vivo evidence for a complex non-linear relationship between Armadillo levels, subcellular distribution and

  20. Expression of Tenascin C, EGFR, E-Cadherin, and TTF-1 in Medullary Thyroid Carcinoma and the Correlation with RET Mutation Status

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    Florian Steiner

    2016-07-01

    Full Text Available Tenascin C expression correlates with tumor grade and indicates worse prognosis in several tumors. Epidermal growth factor receptor (EGFR plays an important role in driving proliferation in many tumors. Loss of E-cadherin function is associated with tumor invasion and metastasis. Thyroid transcription factor-1 (TTF-1 is involved in rearranged during transfection (RET transcription in Hirschsprung’s disease. Tenascin C, EGFR, E-cadherin, TTF-1-expression, and their correlations with RET mutation status were investigated in 30 patients with medullary thyroid carcinoma (MTC (n = 26 or C-cell hyperplasia (n = 4. Tenascin C was found in all, EGFR in 4/26, E-cadherin in 23/26, and TTF-1 in 25/26 MTC. Tenascin C correlated significantly with tumor proliferation (overall, r = 0.61, p < 0.005; RET-mutated, r = 0.81, p < 0.01. E-cadherin showed weak correlation, whereas EGFR and TTF-1 showed no significant correlation with tumor proliferation. EGFR, E-cadherin, and TTF-1 showed weak correlation with proliferation of RET-mutated tumors. Correlation between TTF-1 and tenascin C, E-cadherin, and EGFR was r = −0.10, 0.37, and 0.21, respectively. In conclusion, MTC express tenascin C, E-cadherin, and TTF-1. Tenascin C correlates significantly with tumor proliferation, especially in RET-mutated tumors. EGFR is low, and tumors expressing EGFR do not exhibit higher proliferation. TTF-1 does not correlate with RET mutation status and has a weak correlation with tenascin C, E-cadherin, and EGFR expression.

  1. Matrix Metalloproteinases 2 and 9 and E-Cadherin Expression in the Endometrium During the Implantation Window of Infertile Women Before In Vitro Fertilization Treatment

    Science.gov (United States)

    Rocha, Andre M.; Ferreira, Fernando P.; Bonetti, Tatiana C. S.; Serafini, Paulo; Motta, Eduardo L. A.

    2014-01-01

    Objective: To evaluate the expression of endometrial matrix metalloproteinases (MMPs) 2 and 9 and E-cadherin in peri-implantation phase of infertile women who have undergone in vitro fertilization (IVF) cycles. Methods: This prospective study included 51 patients who underwent endometrial biopsy during the receptive phase in a menstrual cycle prior to IVF treatment. The samples were evaluated by tissue microarray for immunohistochemical study. Results: The expression of MMP-2, MMP-9, and E-cadherin in the endometrium prior to IVF treatment was not associated with pregnancy. There was a decrease in E-cadherin immunodetection, the higher the age of the patients, a negative relationship between E-cadherin and MMP-2, and a positive association between MMP-9 and E-cadherin. Conclusions: The MMP-2, MMP-9, and E-cadherin are expressed in the endometrium of infertile patients during the receptive phase of the natural menstrual cycle. However, there is no correlation between the expression of these molecules and the clinical IVF outcomes. PMID:24700054

  2. ERβ1 inhibits the migration and invasion of breast cancer cells through upregulation of E-cadherin in a Id1-dependent manner

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Yan [Breast Disease Center, Southwest Hospital, Third Military Medical University, Chongqing (China); Ming, Jia [Department of Breast, Thyroid and Pancreas Surgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing (China); Xu, Yan [Department of Breast and Thyroid Surgery, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing (China); Zhang, Yi, E-mail: zy53810@163.com [Breast Disease Center, Southwest Hospital, Third Military Medical University, Chongqing (China); Jiang, Jun, E-mail: Jcbd@medmail.com.cn [Breast Disease Center, Southwest Hospital, Third Military Medical University, Chongqing (China)

    2015-02-06

    Highlights: • Expression of ERβ1 was positively correlated with E-cadherin in breast cancer cell. • ERβ1 upregulates E-cadherin expression in breast cancer cell lines. • ERβ1 upregulates E-cadherin expression in a Id1-dependent manner. - Abstract: ERβ1 is a member of the nuclear receptor superfamily of ligand-regulated transcription factors. It plays an important role in regulating the progression of breast cancer. However, the mechanisms of ERβ1 in tumorigenesis, metastasis and prognosis are still not fully clear. In this study, we showed that the expression of ERβ1 was positively correlated with E-cadherin expression in breast cancer cell lines. In addition, we found that ERβ1 upregulates E-cadherin expression in breast cancer cell lines. Furthermore, we also found that ERβ1 inhibits the migration and invasion of breast cancer cells and upregulated E-cadherin expression in a Id1-dependent manner. Taken together, our study provides further understanding of the molecular mechanism of ERβ1 in tumor metastasis and suggests the feasibility of developing novel therapeutic approaches to target Id1 to inhibit breast cancer metastasis.

  3. Expression of Tenascin C, EGFR, E-Cadherin, and TTF-1 in Medullary Thyroid Carcinoma and the Correlation with RET Mutation Status.

    Science.gov (United States)

    Steiner, Florian; Hauser-Kronberger, Cornelia; Rendl, Gundula; Rodrigues, Margarida; Pirich, Christian

    2016-07-09

    Tenascin C expression correlates with tumor grade and indicates worse prognosis in several tumors. Epidermal growth factor receptor (EGFR) plays an important role in driving proliferation in many tumors. Loss of E-cadherin function is associated with tumor invasion and metastasis. Thyroid transcription factor-1 (TTF-1) is involved in rearranged during transfection (RET) transcription in Hirschsprung's disease. Tenascin C, EGFR, E-cadherin, TTF-1-expression, and their correlations with RET mutation status were investigated in 30 patients with medullary thyroid carcinoma (MTC) (n = 26) or C-cell hyperplasia (n = 4). Tenascin C was found in all, EGFR in 4/26, E-cadherin in 23/26, and TTF-1 in 25/26 MTC. Tenascin C correlated significantly with tumor proliferation (overall, r = 0.61, p C, E-cadherin, and EGFR was r = -0.10, 0.37, and 0.21, respectively. In conclusion, MTC express tenascin C, E-cadherin, and TTF-1. Tenascin C correlates significantly with tumor proliferation, especially in RET-mutated tumors. EGFR is low, and tumors expressing EGFR do not exhibit higher proliferation. TTF-1 does not correlate with RET mutation status and has a weak correlation with tenascin C, E-cadherin, and EGFR expression.

  4. Altered expression of epithelial junctional proteins in atopic asthma: Possible role in inflammation

    NARCIS (Netherlands)

    W.I. de Boer (Pim); H.S. Sharma (Hari); S.M. Baelemans (Sophia); H.C. Hoogsteden (Henk); B.N.M. Lambrecht (Bart); G.J. Braunstahl (Gert-Jan)

    2008-01-01

    textabstractEpithelial cells form a tight barrier against environmental stimuli via tight junctions (TJs) and adherence junctions (AJs). Defects in TJ and AJ proteins may cause changes in epithelial morphology and integrity and potentially lead to faster trafficking of inflammatory cells through the

  5. Transitions of protein traffic from cardiac ER to junctional SR.

    Science.gov (United States)

    Sleiman, Naama H; McFarland, Timothy P; Jones, Larry R; Cala, Steven E

    2015-04-01

    The junctional sarcoplasmic reticulum (jSR) is an important and unique ER subdomain in the adult myocyte that concentrates resident proteins to regulate Ca(2+) release. To investigate cellular mechanisms for sorting and trafficking proteins to jSR, we overexpressed canine forms of junctin (JCT) or triadin (TRD) in adult rat cardiomyocytes. Protein accumulation over time was visualized by confocal fluorescence microscopy using species-specific antibodies. Newly synthesized JCTdog and TRDdog appeared by 12-24h as bright fluorescent puncta close to the nuclear surface, decreasing in intensity with increasing radial distance. With increasing time (24-48h), fluorescent puncta appeared at further radial distances from the nuclear surface, eventually populating jSR similar to steady-state patterns. CSQ2-DsRed, a form of CSQ that polymerizes ectopically in rough ER, prevented anterograde traffic of newly made TRDdog and JCTdog, demonstrating common pathways of intracellular trafficking as well as in situ binding to CSQ2 in juxtanuclear rough ER. Reversal of CSQ-DsRed interactions occurred when a form of TRDdog was used in which CSQ2-binding sites are removed ((del)TRD). With increasing levels of expression, CSQ2-DsRed revealed a novel smooth ER network that surrounds nuclei and connects the nuclear axis. TRDdog was retained in smooth ER by binding to CSQ2-DsRed, but escaped to populate jSR puncta. TRDdog and (del)TRD were therefore able to elucidate areas of ER-SR transition. High levels of CSQ2-DsRed in the ER led to loss of jSR puncta labeling, suggesting a plasticity of ER-SR transition sites. We propose a model of ER and SR protein traffic along microtubules, with prominent transverse/radial ER trafficking of JCT and TRD along Z-lines to populate jSR, and an abundant longitudinal/axial smooth ER between and encircling myonuclei, from which jSR proteins traffic.

  6. Transitions of protein traffic from cardiac ER to junctional SR

    Science.gov (United States)

    Sleiman, Naama H.; McFarland, Timothy P.; Jones, Larry R.; Cala, Steven E.

    2015-01-01

    The junctional sarcoplasmic reticulum (jSR) is an important and unique ER subdomain in the adult myocyte that concentrates resident proteins to regulate Ca2+ release. To investigate cellular mechanisms for sorting and trafficking proteins to jSR, we overexpressed canine forms of junctin (JCT) or triadin (TRD) in adult rat cardiomyocytes. Protein accumulation over time was visualized by confocal fluorescence microscopy using species-specific antibodies. Newly synthesized JCTdog and TRDdog appeared by 12-24 h as bright fluorescent puncta close to the nuclear surface, decreasing in intensity with increasing radial distance. With increasing time (24-48 h), fluorescent puncta appeared at further radial distances from the nuclear surface, eventually populating jSR similar to steady-state patterns. CSQ2-DsRed, a form of CSQ that polymerizes ectopically in rough ER, prevented anterograde traffic of newly made TRDdog and JCTdog, demonstrating common pathways of intracellular trafficking as well as in situ binding to CSQ2 in juxtanuclear rough ER. Reversal of CSQD-sRed interactions occurred when a form of TRDdog was used in which CSQ2-binding sites are removed (delTRD). With increasing levels of expression, CSQ2-DsRed revealed a novel smooth ER network that surrounds nuclei and connects the nuclear axis. TRDdog was retained in smooth ER by binding to CSQ2-DsRed, but escaped to populate jSR puncta. TRDdog and del TRD were therefore able to elucidate areas of ER-SR transition. High levels of CSQ2-DsRed in the ER led to loss of jSR puncta labeling, suggesting a plasticity of ER-SR transition sites. We propose a model of ER and SR protein traffic along microtubules, with prominent transverse/radial ER trafficking of JCT and TRD along Z-lines to populate jSR, and an abundant longitudinal/axial smooth ER between and encircling myonuclei, from which jSR proteins traffic. PMID:25640161

  7. Structural alteration of tight and adherens junctions in villous and crypt epithelium of the small and large intestine of conventional nursing piglets infected with porcine epidemic diarrhea virus.

    Science.gov (United States)

    Jung, Kwonil; Eyerly, Bryan; Annamalai, Thavamathi; Lu, Zhongyan; Saif, Linda J

    2015-06-12

    Integrity of the intestinal epithelium is critical for proper functioning of the barrier that regulates absorption of water and restricts uptake of luminal bacteria. It is maintained mainly by tight junctions (TJs) and adherens junctions (AJs). We conducted immunofluorescence (IF) staining for in situ identification of zonula occludin (ZO)-1 proteins for TJ and E-Cadherin proteins for AJ in the small and large intestinal villous and crypt epithelium of nursing pigs infected with porcine epidemic diarrhea virus (PEDV). Twenty 9-day-old piglets [PEDV-infected (n=9) and Mock (n=11)] from PEDV seronegative sows, were orally inoculated [8.9 log₁₀ genomic equivalents/pig] with PEDV PC21A strain or mock. At post-inoculation days (PIDs) 1-5, infected pigs showed severe watery diarrhea and/or vomiting and severe atrophic enteritis. By immunohistochemistry, PEDV antigens were evident in enterocytes lining the villous epithelium. At PIDs 1-5, PEDV-infected pigs exhibited mildly to extensively disorganized, irregular distribution and reduced expression of ZO-1 or E-Cadherin in villous, but not crypt epithelial cells of the jejunum and ileum, but not in the large intestine, when compared to the negative controls. The structural destruction and disorganization of TJ and AJ were extensive in PEDV-infected pigs at PIDs 1-3, but then appeared to reversibly recover at PID 5, as evident by increased numbers of ZO-1-positive epithelial cells and markedly improved appearance of E-Cadherin-positive villous epithelium. Our results suggest a possible involvement of structurally impaired TJ and AJ in the pathogenesis of PEDV, potentially leading to secondary bacterial infections.

  8. Celastrol inhibits TGF-β1-induced epithelial–mesenchymal transition by inhibiting Snail and regulating E-cadherin expression

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Hyereen; Lee, Minjae [Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul 138-736 (Korea, Republic of); Jang, Sung-Wuk, E-mail: swjang@amc.seoul.kr [Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul 138-736 (Korea, Republic of); Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine, Seoul 138-736 (Korea, Republic of)

    2013-08-09

    Highlights: •We investigated the effects of celastrol on TGF-β1-induced EMT in epithelial cells. •Celastrol regulates TGF-β1-induced morphological changes and E-cadherin expression. •Celastrol inhibits TGF-β1-induced Snail expression. •Celastrol strongly suppresses TGF-β1-induced invasion in MDCK and A549 cells. -- Abstract: The epithelial–mesenchymal transition (EMT) is a pivotal event in the invasive and metastatic potentials of cancer progression. Celastrol inhibits the proliferation of a variety of tumor cells including leukemia, glioma, prostate, and breast cancer; however, the possible role of celastrol in the EMT is unclear. We investigated the effect of celastrol on the EMT. Transforming growth factor-beta 1 (TGF-β1) induced EMT-like morphologic changes and upregulation of Snail expression. The downregulation of E-cadherin expression and upregulation of Snail in Madin–Darby Canine Kidney (MDCK) and A549 cell lines show that TGF-β1-mediated the EMT in epithelial cells; however, celastrol markedly inhibited TGF-β1-induced morphologic changes, Snail upregulation, and E-cadherin expression. Migration and invasion assays revealed that celastrol completely inhibited TGF-β1-mediated cellular migration in both cell lines. These findings indicate that celastrol downregulates Snail expression, thereby inhibiting TGF-β1-induced EMT in MDCK and A549 cells. Thus, our findings provide new evidence that celastrol suppresses lung cancer invasion and migration by inhibiting TGF-β1-induced EMT.

  9. Expression of E-Cadherin, Leukemia Inhibitory Factor and Progesterone Receptor in Mouse Blastocysts after Ovarian Stimulation

    Directory of Open Access Journals (Sweden)

    Bahar Movaghar

    2012-01-01

    Full Text Available Objective: The appropriate interaction between a blastocyst and the endometrium is essential for successful implantation. Numerous factors, including hormone receptors (progesterone receptor, cytokines [leukemia inhibitory factors (LIF], and adherence molecules such as E-cadherin are involved in the cross-talk that occurs between the embryo and endometrium. Studies show that a lack of these genes impact endometrial receptivity. In this study, we compare the expression levels of E-cadherin, LIF, and progesterone receptor (PgR genes in blastocysts that have been obtained from superovulated mice to those obtained from natural cycles.Materials and Methods: In this experimental study, for the experimental group, a total of 17 virgin female NMRI mice (6- 8 weeks old were injected with 7.5 IU pregnant mare serum gonadotropin (PMSG. Their blastocysts (approximately n= 120 were flushed out after 3.5 days, following administration of human chorionic gonadotropin (hCG. The control group consisted of blastocysts from 62 female mice that were mated with male mice. The natural cycle blastocysts were flushed out from the female mice uteri 3.5 days after mating. The expression levels of E-cadherin, LIF, t PgR genes were examined by quantitative real-time reverse-transcriptase polymerase chain reaction (RT-PCR. Data were analyzed by the student’s t-test (one sample t-test.Results: Expression levels of all studied genes were significantly lower in the hormone-treated group compared to the natural cycle blastocysts (p<0.05.Conclusion: Although ovarian stimulation is utilized to obtain more oocytes in ART cycles, it seems that this could disadvantageous to implantation because of the decrease in expression levels of certain genes. Because of the important roles of E-cadherin, LIF, and progesterone receptor in the implantation process, we have shown lower expression levels of these genes in mouse blastocysts obtained from ovarian-stimulated mice than those derived

  10. Positive expression of LSD1 and negative expression of E-cadherin correlate with metastasis and poor prognosis of colon cancer.

    Science.gov (United States)

    Jie, Ding; Zhongmin, Zhang; Guoqing, Liao; Sheng, Liu; Yi, Zhang; Jing, Wen; Liang, Zeng

    2013-06-01

    The first identified lysine-specific demethylase, LSD1, plays an important role in the metastatic progression of several types of cancer. The aim of this study was to investigate LSD1, E-cadherin, and N-cadherin expression in colon cancer specimens and their clinical significance. The expression of LSD1, E-cadherin, and N-cadherin in colon cancer specimens was determined by immunohistochemistry, and the relationship between the expression of the respective molecules and clinicopathological characteristics was analyzed. The positive expression rates of LSD1, E-cadherin, and N-cadherin in colon cancer specimens were 66.7 % (72/108), 85.2 % (92/108), and 41.7 % (45/108), respectively. LSD1 was significantly more highly expressed in colon cancer specimens classified as high TNM stage lesions and with distant metastasis (P colon cancer specimens classified as high TNM stage lesions and with distant metastasis (P 0.05). Correlation analysis revealed that LSD1 expression was negatively correlated with E-cadherin expression (r s = -0.318, P = 0.001), but not evidently correlated with N-cadherin expression (r s = 0.182, P = 0.06). Colon cancer specimens with positive LSD1 expression and negative E-cadherin expression were correlated with significantly lower overall survival. LSD1 showed a significantly higher expression, in contrast to the significantly lower expression of E-cadherin, in colon cancer specimens classified as high TNM stage lesions and with distant metastasis. Positive expression of LSD1 and negative expression of E-cadherin may be predictors of a worse colon cancer prognosis.

  11. Down regulation of E-Cadherin (ECAD - a predictor for occult metastatic disease in sentinel node biopsy of early squamous cell carcinomas of the oral cavity and oropharynx

    Directory of Open Access Journals (Sweden)

    Studer Gabriela

    2011-06-01

    Full Text Available Abstract Background Prognostic factors in predicting occult lymph node metastasis in patients with head and neck squamous-cell carcinoma (HNSCC are necessary to improve the results of the sentinel lymph node procedure in this tumour type. The E-Cadherin glycoprotein is an intercellular adhesion molecule in epithelial cells, which plays an important role in establishing and maintaining intercellular connections. Objectives To determine the value of the molecular marker E-Cadherin in predicting regional metastatic disease. Methods E-Cadherin expression in tumour tissue of 120 patients with HNSCC of the oral cavity and oropharynx were evaluated using the tissue microarray technique. 110 tumours were located in the oral cavity (91.7%; mostly tongue, 10 tumours in the oropharynx (8.3%. Intensity of E-Cadherin expression was quantified by the Intensity Reactivity Score (IRS. These results were correlated with the lymph node status of biopsied sentinel lymph nodes. Univariate and multivariate analysis was used to determine statistical significance. Results pT-stage, gender, tumour side and location did not correlate with lymph node metastasis. Differentiation grade (p = 0.018 and down regulation of E-Cadherin expression significantly correlate with positive lymph node status (p = 0.005 in univariate and multivariate analysis. Conclusion These data suggest that loss of E-cadherin expression is associated with increased lymhogeneous metastasis of HNSCC. E-cadherin immunohistochemistry may be used as a predictor for lymph node metastasis in squamous cell carcinoma of the oral cavity and oropharynx. Level of evidence: 2b

  12. Notch signaling-mediated cell-to-cell interaction is dependent on E-cadherin adhesion in adult rat anterior pituitary.

    Science.gov (United States)

    Batchuluun, Khongorzul; Azuma, Morio; Yashiro, Takashi; Kikuchi, Motoshi

    2016-12-10

    The rat anterior pituitary is composed of hormone-producing cells, non-hormone-producing cells (referred to as folliculostellate cells) and marginal layer cells. In the adult rat, progenitor cells of hormone-producing cells have recently been reported to be maintained within this non-hormone-producing cell population. In tissue, non-hormone-producing cells construct homophilic cell aggregates by the differential expression of the cell adhesion molecule E-cadherin. We have previously shown that Notch signaling, a known regulator of progenitor cells in a number of organs, is activated in the cell aggregates. We now investigate the relationship between Notch signaling and E-cadherin-mediated cell adhesion in the pituitary gland. Immunohistochemically, Notch signaling receptor Notch2 and the ligand Jagged1 were localized within E-cadherin-positive cells in the marginal cell layer and in the main part of the anterior lobe, whereas Notch1 was localized in E-cadherin-positive and -negative cells. Activation of Notch signaling within E-cadherin-positive cells was confirmed by immunostaining of the Notch target HES1. Notch2 and Jagged1 were always co-localized within the same cells suggesting that homologous cells have reciprocal effects in activating Notch signaling. When the E-cadherin function was inhibited by exposure to a monoclonal antibody (DECMA-1) in primary monolayer cell culture, the percentage of HES1-positive cells among Notch2-positive cells was less than half that of the control. The present results suggest that E-cadherin-mediated cell attachment is necessary for the activation of Notch signaling in the anterior pituitary gland but not for the expression of the Notch2 molecule.

  13. Formation of post-confluence structure in human parotid gland acinar cells on PLGA through regulation of E-cadherin.

    Science.gov (United States)

    Chan, Yen-Hui; Huang, Tsung-Wei; Chou, Ya-Shuan; Hsu, Sheng-Hao; Su, Wei-Fang; Lou, Pei-Jen; Young, Tai-Horng

    2012-01-01

    As a potential solution for patients to retrieve their lost salivary gland functions, tissue engineering of an auto-secretory device is profoundly needed. Under serum-free environment, primary human parotid gland acinar (PGAC) cells can be obtained. After reaching confluence, PGAC cells spontaneously form three-dimension (3D) cell aggregations, termed post-confluence structure (PCS), and change their behaviors. Poly (lactic-co-glycolic acid) (PLGA) has been widely used in the field of biomedical applications because of its biodegradable properties for desired functions. Nonetheless, the role of PLGA in facilitating PGAC cells to form PCS has seldom been explored to recover epithelial characteristics. In this study, PGAC cells were found to have a greater tendency to form PCS on PLGA than on tissue culture polystyrene (TCPS). By tracing cell migration paths and modulating E-cadherin activity with specific inhibitor or antibody, we demonstrated that the static force of homophilic interaction on surfaces of individual cells, but not the dynamics of cell migration, played a more important role in PCS formation. Thus, PLGA was successfully confirmed to support PGAC cells to form more PCS through the effects on enhancing E-cadherin expression, which is associated with FAK/ILK/Snail expression in PGAC cells. This result indicates that selective appropriate biomaterials may be potentially useful in generating 3D PCS on two-dimension (2D) substrate without fabricating a complex 3D scaffold.

  14. Celastrol inhibits TGF-β1-induced epithelial-mesenchymal transition by inhibiting Snail and regulating E-cadherin expression.

    Science.gov (United States)

    Kang, Hyereen; Lee, Minjae; Jang, Sung-Wuk

    2013-08-09

    The epithelial-mesenchymal transition (EMT) is a pivotal event in the invasive and metastatic potentials of cancer progression. Celastrol inhibits the proliferation of a variety of tumor cells including leukemia, glioma, prostate, and breast cancer; however, the possible role of celastrol in the EMT is unclear. We investigated the effect of celastrol on the EMT. Transforming growth factor-beta 1 (TGF-β1) induced EMT-like morphologic changes and upregulation of Snail expression. The downregulation of E-cadherin expression and upregulation of Snail in Madin-Darby Canine Kidney (MDCK) and A549 cell lines show that TGF-β1-mediated the EMT in epithelial cells; however, celastrol markedly inhibited TGF-β1-induced morphologic changes, Snail upregulation, and E-cadherin expression. Migration and invasion assays revealed that celastrol completely inhibited TGF-β1-mediated cellular migration in both cell lines. These findings indicate that celastrol downregulates Snail expression, thereby inhibiting TGF-β1-induced EMT in MDCK and A549 cells. Thus, our findings provide new evidence that celastrol suppresses lung cancer invasion and migration by inhibiting TGF-β1-induced EMT. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. E-cadherin cytoplasmic domain inhibits cell surface localization of endogenous cadherins and fusion of C2C12 myoblasts

    Directory of Open Access Journals (Sweden)

    Masayuki Ozawa

    2015-11-01

    Full Text Available Myoblast fusion is a highly regulated process that is essential for skeletal muscle formation during muscle development and regeneration in mammals. Much remains to be elucidated about the molecular mechanism of myoblast fusion although cadherins, which are Ca2+-dependent cell–cell adhesion molecules, are thought to play a critical role in this process. Mouse myoblasts lacking either N-cadherin or M-cadherin can still fuse to form myotubes, indicating that they have no specific function in this process and may be functionally replaced by either M-cadherin or N-cadherin, respectively. In this study, we show that expressing the E-cadherin cytoplasmic domain ectopically in C2C12 myoblasts inhibits cell surface localization of endogenous M-cadherin and N-cadherin, as well as cell–cell fusion. This domain, however, does not inhibit myoblast differentiation according to microarray-based gene expression analysis. In contrast, expressing a dominant-negative β-catenin mutant ectopically, which suppresses Wnt/β-catenin signaling, did not inhibit cell–cell fusion. Therefore, the E-cadherin cytoplasmic domain inhibits cell–cell fusion by inhibiting cell surface localization of endogenous cadherins and not by inhibiting Wnt/β-catenin signaling.

  16. Mammary-specific inactivation of E-cadherin and p53 impairs functional gland development and leads to pleomorphic invasive lobular carcinoma in mice

    Directory of Open Access Journals (Sweden)

    Patrick W. B. Derksen

    2011-05-01

    Breast cancer is the most common malignancy in women of the Western world. Even though a large percentage of breast cancer patients show pathological complete remission after standard treatment regimes, approximately 30–40% are non-responsive and ultimately develop metastatic disease. To generate a good preclinical model of invasive breast cancer, we have taken a tissue-specific approach to somatically inactivate p53 and E-cadherin, the cardinal cell-cell adhesion receptor that is strongly associated with tumor invasiveness. In breast cancer, E-cadherin is found mutated or otherwise functionally silenced in invasive lobular carcinoma (ILC, which accounts for 10–15% of all breast cancers. We show that mammary-specific stochastic inactivation of conditional E-cadherin and p53 results in impaired mammary gland function during pregnancy through the induction of anoikis resistance of mammary epithelium, resulting in loss of epithelial organization and a dysfunctional mammary gland. Moreover, combined inactivation of E-cadherin and p53 induced lactation-independent development of invasive and metastatic mammary carcinomas, which showed strong resemblance to human pleomorphic ILC. Dissemination patterns of mouse ILC mimic the human malignancy, showing metastasis to the gastrointestinal tract, peritoneum, lung, lymph nodes and bone. Our results confirm that loss of E-cadherin contributes to both mammary tumor initiation and metastasis, and establish a preclinical mouse model of human ILC that can be used for the development of novel intervention strategies to treat invasive breast cancer.

  17. JianPi JieDu Recipe Inhibits Epithelial-to-Mesenchymal Transition in Colorectal Cancer through TGF-β/Smad Mediated Snail/E-Cadherin Expression

    Directory of Open Access Journals (Sweden)

    Xuan Liu

    2017-01-01

    Full Text Available JPJD was an ideal alternative traditional Chinese medicine compound in the prevention and treatment of CRC, but its underlying mechanisms has not been fully elucidated. In this study, we demonstrated in vitro that TGF-β-induced EMT promoted the invasion and metastasis of CRC cells, reduced the expression of E-cadherin, and elevated the expression of Vimentin. However, JPJD could inhibit the invasive and migratory ability of TGF-β-stimulated CRC cells in a concentration-dependent manner through increasing the expression of E-cadherin and repressing the expression of Vimentin, as well as the inhibition of TGF-β/Smad signaling pathway. Meanwhile, JPJD reduced the transcriptional activities of EMT-associated factors Snail and E-cadherin during the initiation of TGF-β-induced EMT. In vivo, the results demonstrated that JPJD can significantly inhibit the liver and lung metastasis of orthotopic CRC tumor in nude mice, as well as significantly prolonging the survival time of tumor-bearing in a dose-dependent manner. Additionally, JPJD can upregulate the expression of E-cadherin and Smad2/3 in the cytoplasm and downregulate the expression of Vimentin, p-Smad2/3, and Snail in the orthotopic CRC tumor tissues. In conclusions, our new findings provided evidence that JPJD could inhibit TGF-β-induced EMT in CRC through TGF-β/Smad mediated Snail/E-cadherin expression.

  18. Histone deacetylase inhibitor entinostat reverses epithelial to mesenchymal transition of breast cancer cells by reversing the repression of E-cadherin.

    Science.gov (United States)

    Shah, Preeti; Gau, Yael; Sabnis, Gauri

    2014-01-01

    Loss of ERα in breast cancer correlates with poor prognosis, increased recurrence rates, and higher incidence of metastasis. Epigenetic silencing of E-cadherin (loss of which is associated with more invasive phenotype) is observed in metastatic cell lines and invasive breast cancers. Here, we are showing that entinostat (ENT) can reverse epithelial to mesenchymal transition (EMT), which is considered to be a first step in the process of metastases formation. Triple-negative breast cancer cells such as MDA-MB-231 and Hs578T show a basal phenotype characterized by loss of E-cadherin expression and higher expression of mesenchymal markers such as N-cadherin and vimentin along with transcriptional repressors such as twist and snail. When MDA-MB-231 and Hs578T cells or tumors were treated with ENT, E-cadherin transcription was increased along with reduction in N-cadherin mRNA expression. Chromatin immunoprecipitation assay showed that treatment of MDA-MB-231 and Hs578T cells increased the activation of E-cadherin promoter by reducing the association of twist and snail with the E-cadherin (CDH1) promoter and downregulated both the snail and twist. ENT also inhibited cell migration in vitro. In addition, phosphorylation of vimentin was increased, as well as remodeling of vimentin filaments. ENT treatment also reduced formation of tubulin-based microtentacles, which help floating cells attach to other surfaces. These findings suggest that ENT can reverse EMT and may reduce the formation of metastasis.

  19. Induction of the LRP16 gene by estrogen promotes the invasive growth of Ishikawa human endometrial cancer cells through the downregulation of E-cadherin

    Institute of Scientific and Technical Information of China (English)

    Yuan Guang Meng; Wei Dong Han; Ya Li Zhao; Ke Huang; Yi Ling Si; Zhi Qiang Wu; Yi Ming Mu

    2007-01-01

    LRP16 was previously identified as an estrogen-induced gene in breast cancer cells.The responsiveness of LRPl6to estrogen and its functional effects in endometrial cancer(EC)cells are still unclear.Here,we show that the mRNAlevel and promoter activity of the LRP16 gene were significantly increased by 17β-estradiol(E2)in estrogen receptorα(ERα)-positive Ishikawa human EC cells.Although the growth rate of Ishikawa cells was not obviously affected byectopic expression of LIP16,the results of a Transwell assay showed an approximate one-third increase of the invasivecapacity of LRP16-overexpressing cells.As a result of molecular screening,we observed that the expression of E-cadherin,an essential adhesion molecule associated with tumor metastasis,was repressed by LRP16.Further promoter analysesdemonstrated that LRP16 inhibited E-cadherin transactivation in a dose-dependent manner.However,the inhibition wasabolished by estrogen deprivation.indicating that the downregulation of E-cadherin transcription by LRP16 requiresERa mediation.Chromatin immunoprecipitation analyses revealed that the binding of ERa to the E-cadherin promoterwas antagonized by LRP16,suggesting that LRP16 could interfere with ERα-mediated transcription.These results sug-gest that the upregulation of LRP16 by estrogen could be involved in invasive growth by downregulating E-cadherin inhuman ECs.

  20. Do cell junction protein mutations cause an airway phenotype in mice or humans?

    Science.gov (United States)

    Chang, Eugene H; Pezzulo, Alejandro A; Zabner, Joseph

    2011-08-01

    Cell junction proteins connect epithelial cells to each other and to the basement membrane. Genetic mutations of these proteins can cause alterations in some epithelia leading to varied phenotypes such as deafness, renal disease, skin disorders, and cancer. This review examines if genetic mutations in these proteins affect the function of lung airway epithelia. We review cell junction proteins with examples of disease mutation phenotypes in humans and in mouse knockout models. We also review which of these genes are expressed in airway epithelium by microarray expression profiling and immunocytochemistry. Last, we present a comprehensive literature review to find the lung phenotype when cell junction and adhesion genes are mutated or subject to targeted deletion. We found that in murine models, targeted deletion of cell junction and adhesion genes rarely result in a lung phenotype. Moreover, mutations in these genes in humans have no obvious lung phenotype. Our research suggests that simply because a cell junction or adhesion protein is expressed in an organ does not imply that it will exhibit a drastic phenotype when mutated. One explanation is that because a functioning lung is critical to survival, redundancy in the system is expected. Therefore mutations in a single gene might be compensated by a related function of a similar gene product. Further studies in human and animal models will help us understand the overlap in the function of cell junction gene products. Finally, it is possible that the human lung phenotype is subtle and has not yet been described.

  1. Tight junction-associated MARVEL proteins marveld3, tricellulin, and occludin have distinct but overlapping functions.

    Science.gov (United States)

    Raleigh, David R; Marchiando, Amanda M; Zhang, Yong; Shen, Le; Sasaki, Hiroyuki; Wang, Yingmin; Long, Manyuan; Turner, Jerrold R

    2010-04-01

    In vitro studies have demonstrated that occludin and tricellulin are important for tight junction barrier function, but in vivo data suggest that loss of these proteins can be overcome. The presence of a heretofore unknown, yet related, protein could explain these observations. Here, we report marvelD3, a novel tight junction protein that, like occludin and tricellulin, contains a conserved four-transmembrane MARVEL (MAL and related proteins for vesicle trafficking and membrane link) domain. Phylogenetic tree reconstruction; analysis of RNA and protein tissue distribution; immunofluorescent and electron microscopic examination of subcellular localization; characterization of intracellular trafficking, protein interactions, dynamic behavior, and siRNA knockdown effects; and description of remodeling after in vivo immune activation show that marvelD3, occludin, and tricellulin have distinct but overlapping functions at the tight junction. Although marvelD3 is able to partially compensate for occludin or tricellulin loss, it cannot fully restore function. We conclude that marvelD3, occludin, and tricellulin define the tight junction-associated MARVEL protein family. The data further suggest that these proteins are best considered as a group with both redundant and unique contributions to epithelial function and tight junction regulation.

  2. Probing the interaction between cHAVc3 peptide and the EC1 domain of E-cadherin using NMR and molecular dynamics simulations.

    Science.gov (United States)

    Alaofi, Ahmed; Farokhi, Elinaz; Prasasty, Vivitri D; Anbanandam, Asokan; Kuczera, Krzysztof; Siahaan, Teruna J

    2017-01-01

    The goal of this work is to probe the interaction between cyclic cHAVc3 peptide and the EC1 domain of human E-cadherin protein. Cyclic cHAVc3 peptide (cyclo(1,6)Ac-CSHAVC-NH2) binds to the EC1 domain as shown by chemical shift perturbations in the 2D (1)H,-(15)N-HSQC NMR spectrum. The molecular dynamics (MD) simulations of the EC1 domain showed folding of the C-terminal tail region into the main head region of the EC1 domain. For cHAVc3 peptide, replica exchange molecular dynamics (REMD) simulations generated five structural clusters of cHAVc3 peptide. Representative structures of cHAVc3 and the EC1 structure from MD simulations were used in molecular docking experiments with NMR constraints to determine the binding site of the peptide on EC1. The results suggest that cHAVc3 binds to EC1 around residues Y36, S37, I38, I53, F77, S78, H79, and I94. The dissociation constants (Kd values) of cHAVc3 peptide to EC1 were estimated using the NMR chemical shifts data and the estimated Kds are in the range of .5 × 10(-5)-7.0 × 10(-5) M.

  3. The Hedgehog Inhibitor Cyclopamine Reduces β-Catenin-Tcf Transcriptional Activity, Induces E-Cadherin Expression, and Reduces Invasion in Colorectal Cancer Cells

    Energy Technology Data Exchange (ETDEWEB)

    Qualtrough, David, E-mail: david.qualtrough@uwe.ac.uk [Department of Biological, Biomedical & Analytical Sciences, University of the West of England, Faculty of Health and Applied Sciences, University of the West of England, Frenchay, Bristol BS16 1QY (United Kingdom); Rees, Phil; Speight, Beverley; Williams, Ann C.; Paraskeva, Christos [School of Cellular & Molecular Medicine, University of Bristol, Medical Sciences Building, University Walk, Bristol BS8 1TD (United Kingdom)

    2015-09-17

    Colorectal cancer is a major global health problem resulting in over 600,000 deaths world-wide every year with the majority of these due to metastatic disease. Wnt signalling, and more specifically β-catenin-related transcription, has been shown to drive both tumorigenesis and the metastatic process in colorectal neoplasia, yet its complex interactions with other key signalling pathways, such as hedgehog, remain to be elucidated. We have previously shown that the Hedgehog (HH) signalling pathway is active in cells from colorectal tumours, and that inhibition of the pathway with cyclopamine induces apoptosis. We now show that cyclopamine treatment reduces β-catenin related transcription in colorectal cancer cell lines, and that this effect can be reversed by addition of Sonic Hedgehog protein. We also show that cyclopamine concomitantly induces expression of the tumour suppressor and prognostic indicator E-cadherin. Consistent with a role for HH in regulating the invasive potential we show that cyclopamine reduces the expression of transcription factors (Slug, Snail and Twist) associated with the epithelial-mesenchymal transition and reduces the invasiveness of colorectal cancer cells in vitro. Taken together, these data show that pharmacological inhibition of the hedgehog pathway has therapeutic potential in the treatment of colorectal cancer.

  4. Analysis of cytoskeleton dynamics and cell migration in drosophila ovaries using GFP-actin and E-cadherin-GFP fusion molecules

    Science.gov (United States)

    Verkhusha, Vladyslav V.; Tsukita, Shoichiro; Oda, Hiroki

    1999-06-01

    Coordination of cell migration and adhesion is essential for movement of tissues during morphogenesis. During Drosophila oogenesis so called border cells (BCs) break from an anterior epithelium of egg chamber, acquire a mesenchymal-like morphology, and migrate posteriorly between nurse cells to oocyte. The confocal microscopic observation of BCs has revealed well-developed forepart lamellipodium stained with Drosophila E-cadherin (DE-cadherin), PS2 integrin, cytoplasmic myosin and F-actin. To investigate mechanism of BC migration in vivo we have constructed a DE-cadherin-GFP and a GFP-actin fusion proteins and induced their expression BCs utilizing the UAS/GAL4 system. The DE-cadherin-GFP signal as well as immunostaining of PS2 integrin visualized a track of migrating BCs providing an evidence that adhesive molecules are pulled out and left behind on the surface of nurse cells. Our data suggest that two distinct adhesive systems, DE-cadherins and PS2 integrins simultaneously mediate the migration of BCs. Release of adhesive contacts in the tail region is a rate- limited event in BC migration. The spatial-temporal sequence of actin-based events visualized by the GFP-actin suggest a treadmilling model for actin behavior in BC lamellipodium. BC migration can be considered as simultaneous reiterating processes of lamellipodium extension and adhesive attachment, cytoskeletal contraction, and rear detachment.

  5. The Hedgehog Inhibitor Cyclopamine Reduces β-Catenin-Tcf Transcriptional Activity, Induces E-Cadherin Expression, and Reduces Invasion in Colorectal Cancer Cells

    Directory of Open Access Journals (Sweden)

    David Qualtrough

    2015-09-01

    Full Text Available Colorectal cancer is a major global health problem resulting in over 600,000 deaths world-wide every year with the majority of these due to metastatic disease. Wnt signalling, and more specifically β-catenin-related transcription, has been shown to drive both tumorigenesis and the metastatic process in colorectal neoplasia, yet its complex interactions with other key signalling pathways, such as hedgehog, remain to be elucidated. We have previously shown that the Hedgehog (HH signalling pathway is active in cells from colorectal tumours, and that inhibition of the pathway with cyclopamine induces apoptosis. We now show that cyclopamine treatment reduces β-catenin related transcription in colorectal cancer cell lines, and that this effect can be reversed by addition of Sonic Hedgehog protein. We also show that cyclopamine concomitantly induces expression of the tumour suppressor and prognostic indicator E-cadherin. Consistent with a role for HH in regulating the invasive potential we show that cyclopamine reduces the expression of transcription factors (Slug, Snail and Twist associated with the epithelial-mesenchymal transition and reduces the invasiveness of colorectal cancer cells in vitro. Taken together, Cancers 2015, 7 1886 these data show that pharmacological inhibition of the hedgehog pathway has therapeutic potential in the treatment of colorectal cancer.

  6. The Drosophila genes crumbs and stardust are involved in the biogenesis of adherens junctions.

    Science.gov (United States)

    Grawe, F; Wodarz, A; Lee, B; Knust, E; Skaer, H

    1996-03-01

    Morphogenetic movements of epithelia during development underlie the normal elaboration of the final body plan. The tissue integrity critical for these movements is conferred by anchorage of the cytoskeleton by adherens junctions, initially spot and later belt-like, zonular structures, which encircle the apical side of the cell. Loss-of-function mutations in the Drosophila genes crumbs and stardust lead to the loss of cell polarity in most ectodermally derived epithelia, followed in some, such as the epidermis, by extensive apoptosis. Here we show that both mutants fail to establish proper zonulae adherentes in the epidermis. Our results suggest that the two genes are involved in different aspects of this process. Further, they are compatible with the hypothesis that crumbs delimits the apical border, where the zonula adherens usually forms and where Crumbs protein is normally most abundant. In contrast, stardust seems to be required at an earlier stage for the assembly of the spot adherence junctions. In both mutants, the defect observed at the ultrastructural level are preceded by a misdistribution of Armadillo and DE-cadherin, the homologues of beta-catenin and E-cadherin, respectively, which are two constituents of the vertebrate adherens junctions. Strikingly, expansion of the apical membrane domain in epidermal cells by overexpression of crumbs also abolishes the formation of adherens junctions and results in the disruption of tissue integrity, but without loss of membrane polarity. This result supports the view that membrane polarity is independent of the formation of adherens junctions in epidermal cells.

  7. Sialylation of E-cadherin does not change the spontaneous or ET-18-OMe-mediated aggregation of MCF-7 human breast cancer cells.

    Science.gov (United States)

    Steelant, W F; Recchi, M A; Noë, V T; Boilly-Marer, Y; Bruyneel, E A; Verbert, A; Mareel, M M; Delannoy, P

    1999-05-01

    We have investigated the role of sialylation on cell-cell adhesion mediated by E-cadherin. Two MCF-7 human breast cancer cell variants were studied: MCF-7/AZ cells showed a spontaneous cell-cell adhesion in the fast and slow aggregation assay. whereas the adhesion deficient MCF-7/6 cell variant failed to form larger aggregates, suggesting that E-cadherin was not functional under the conditions of both assays. We measured the sialyltransferase activities using Galbeta1-3GalNAcalpha-O-benzyl and Galbeta1-4GlcNAcalpha-O-benzyl as acceptor substrates as well as mRNA levels of four sialyltransferases, ST3Gal I, ST3Gal III, ST3Gal IV, ST6Gal I, using multiplex RT-PCR in MCF-7 cell variants. The alpha2-6 and alpha2-3 sialylation of E-cadherin was investigated by immuno-blot using Sambucus nigra agglutinin and Maackia amurensis agglutinin. Compared to the adhesion-proficient MCF-7/AZ cells, the adhesion-deficient MCF-7/6 cell line apparently lacks ST6Gal I mRNA, has a lower ST3Gal I mRNA, a lower ST3Gal I sialyltransferase activity, and no alpha2-3 linked sialic acid moieties on E-cadherin. The potential anti-cancer drug 1-O-octadecyl-2-O-methylglycero-3-phosphocholine (ET-18-OMe, 48 h, 25 microg/ml) belonging to the class of alkyllysophospholipids restored the E-cadherin function in the adhesion-deficient MCF-7/6 cells as evidenced by an increased aggregation. ET-18-OMe caused loss of ST6Gal I mRNA in MCF-7/AZ cells but no changes of sialyltransferase activities or sialic acid moieties on E-cadherin could be observed. We conclude that Ca2+-dependent, E-cadherin-specific homotypic adhesion of MCF-7/AZ or MCF-7/6 cells treated with ET-18-OMe was not affected by sialylation of E-cadherin.

  8. Distribution of E-cadherin and ß-catenin in relation to cell maturation and cell extrusion in rat and mouse small intestines

    DEFF Research Database (Denmark)

    Larsson, Lars-Inge

    2006-01-01

    -cadherin. Thus, all extruded cells as well as all cells in the process of extrusion lacked staining for ß-catenin. Moreover, almost 80% of all cells undergoing programmed cell death, as detected by the TUNEL reaction, lacked ß-catenin whereas over 70% of such cells were positive for E-cadherin. However, most...... ells lacking ß-catenin did not display signs of PCD as detected by the TUNEL method or by staining for active caspase-3. Therefore, these results suggest that loss of ß-catenin precedes the onset of programmed cell death, loss of E-cadherin and extrusion from the villi....

  9. Expression and Clinicopathologic Significance of EpCAM and E-Cadherin in Urothelial Carcinoma of Renal Pelvis%肾盂癌中EpCAM和E-Cadherin的表达及临床意义

    Institute of Scientific and Technical Information of China (English)

    单立平; 卜仁戈; 张墨; 李波; 吴斌; 宋永胜

    2012-01-01

    Objective To investigate the pmgnostic value of EpCAM and E-Cadherin in urothelial carcinoma of rpnal pelvis. Methods Ep-CAM and E-Cadherin were analyzed by immunohistochemistry using monoclonal antiliodies in 50 cases of normal mucosa and 76 cases of urothelial carcinoma of renal pelvis. Results The positive rate of EpCAM in urothelial carcinoma of renal pelvis was 60.5% .which was significantly higher than in para-cancerous mucosa of 27.6%. The expression of EpCAM was significantly related with the differential clinical stage,pathological degree,distant metastasis and bladder tumor recurrence (all P< 0.05). The expression of E-Cadherin was significantly re-lated with the differential clinical stage,pathological degree and distant metastasis (all P < 0.05). There was negative correlation between the expression of EpCAM and E-Cadherin in urothelial carcinoma of renal pelvis ( r =-0.425,P < 0.01). Conclusion The expression EpCAM and E-Cadherin are highly related to occurrence,development,infiltration and metastasis of urothelial carcinoma of renal pelvis,and evaluation of the two proteins could be a very applicable guidance for the diagnosis of metastasis and invasion of urothelial carcinoma of renal pelvis.%目的 探讨EpCAM和E-Cadherin的表达与肾盂癌病理分级和临床分期的关系.方法 应用免疫组织化学SP法检测76例不同级别肾盂癌和50例癌旁正常组织中EpCAM和E-Cadherin的表达.结果 EpCAM在肾盂癌阳性表达率为60.5%(46/76),明显高于癌旁组织27.6%(21/76),差异具有统计学意义(P<0.05);EpCAM的表达与肾盂癌不同临床分期、病理分级、远处转移及继发膀胱肿瘤相关(P<0.05);EpCAM与E-Cadherin在肾盂癌中表达呈负相关(r=-0.425,P< 0.01).结论 EpCAM及E-Cadherin的表达变化与肾盂癌的发生发展、浸润转移有良好的相关性,同步检测二者在肾盂癌组织中的表达并综合分析两者之间的关系对评价肾盂癌的侵袭转移能力判断具有一定价值.

  10. Actin-interacting protein 1 controls assembly and permeability of intestinal epithelial apical junctions.

    Science.gov (United States)

    Lechuga, Susana; Baranwal, Somesh; Ivanov, Andrei I

    2015-05-01

    Adherens junctions (AJs) and tight junctions (TJs) are crucial regulators of the integrity and restitution of the intestinal epithelial barrier. The structure and function of epithelial junctions depend on their association with the cortical actin cytoskeleton that, in polarized epithelial cells, is represented by a prominent perijunctional actomyosin belt. The assembly and stability of the perijunctional cytoskeleton is controlled by constant turnover (disassembly and reassembly) of actin filaments. Actin-interacting protein (Aip) 1 is an emerging regulator of the actin cytoskeleton, playing a critical role in filament disassembly. In this study, we examined the roles of Aip1 in regulating the structure and remodeling of AJs and TJs in human intestinal epithelium. Aip1 was enriched at apical junctions in polarized human intestinal epithelial cells and normal mouse colonic mucosa. Knockdown of Aip1 by RNA interference increased the paracellular permeability of epithelial cell monolayers, decreased recruitment of AJ/TJ proteins to steady-state intercellular contacts, and attenuated junctional reassembly in a calcium-switch model. The observed defects of AJ/TJ structure and functions were accompanied by abnormal organization and dynamics of the perijunctional F-actin cytoskeleton. Moreover, loss of Aip1 impaired the apico-basal polarity of intestinal epithelial cell monolayers and inhibited formation of polarized epithelial cysts in 3-D Matrigel. Our findings demonstrate a previously unanticipated role of Aip1 in regulating the structure and remodeling of intestinal epithelial junctions and early steps of epithelial morphogenesis.

  11. Protein tyrosine phosphatase σ targets apical junction complex proteins in the intestine and regulates epithelial permeability.

    Science.gov (United States)

    Murchie, Ryan; Guo, Cong-Hui; Persaud, Avinash; Muise, Aleixo; Rotin, Daniela

    2014-01-14

    Protein tyrosine phosphatase (PTP)σ (PTPRS) was shown previously to be associated with susceptibility to inflammatory bowel disease (IBD). PTPσ(-/-) mice exhibit an IBD-like phenotype in the intestine and show increased susceptibility to acute models of murine colitis. However, the function of PTPσ in the intestine is uncharacterized. Here, we show an intestinal epithelial barrier defect in the PTPσ(-/-) mouse, demonstrated by a decrease in transepithelial resistance and a leaky intestinal epithelium that was determined by in vivo tracer analysis. Increased tyrosine phosphorylation was observed at the plasma membrane of epithelial cells lining the crypts of the small bowel and colon of the PTPσ(-/-) mouse, suggesting the presence of PTPσ substrates in these regions. Using mass spectrometry, we identified several putative PTPσ intestinal substrates that were hyper-tyrosine-phosphorylated in the PTPσ(-/-) mice relative to wild type. Among these were proteins that form or regulate the apical junction complex, including ezrin. We show that ezrin binds to and is dephosphorylated by PTPσ in vitro, suggesting it is a direct PTPσ substrate, and identified ezrin-Y353/Y145 as important sites targeted by PTPσ. Moreover, subcellular localization of the ezrin phosphomimetic Y353E or Y145 mutants were disrupted in colonic Caco-2 cells, similar to ezrin mislocalization in the colon of PTPσ(-/-) mice following induction of colitis. Our results suggest that PTPσ is a positive regulator of intestinal epithelial barrier, which mediates its effects by modulating epithelial cell adhesion through targeting of apical junction complex-associated proteins (including ezrin), a process impaired in IBD.

  12. E-cadherin acts as a regulator of transcripts associated with a wide range of cellular processes in mouse embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Francesca Soncin

    Full Text Available BACKGROUND: We have recently shown that expression of the cell adhesion molecule E-cadherin is required for LIF-dependent pluripotency of mouse embryonic stem (ES cells. METHODOLOGY: In this study, we have assessed global transcript expression in E-cadherin null (Ecad-/- ES cells cultured in either the presence or absence of LIF and compared these to the parental cell line wtD3. RESULTS: We show that LIF has little effect on the transcript profile of Ecad-/- ES cells, with statistically significant transcript alterations observed only for Sp8 and Stat3. Comparison of Ecad-/- and wtD3 ES cells cultured in LIF demonstrated significant alterations in the transcript profile, with effects not only confined to cell adhesion and motility but also affecting, for example, primary metabolic processes, catabolism and genes associated with apoptosis. Ecad-/- ES cells share similar, although not identical, gene expression profiles to epiblast-derived pluripotent stem cells, suggesting that E-cadherin expression may inhibit inner cell mass to epiblast transition. We further show that Ecad-/- ES cells maintain a functional β-catenin pool that is able to induce β-catenin/TCF-mediated transactivation but, contrary to previous findings, do not display endogenous β-catenin/TCF-mediated transactivation. We conclude that loss of E-cadherin in mouse ES cells leads to significant transcript alterations independently of β-catenin/TCF transactivation.

  13. [18F]Fluoro-2-deoxy-D-glucose positron emission tomography detects gastric carcinoma in an early stage in an asymptomatic E-cadherin mutation carrier.

    NARCIS (Netherlands)

    Kouwen, M.C.A. van; Drenth, J.P.H.; Oyen, W.J.G.; Bruin, J.H.F.M. de; Ligtenberg, M.J.L.; Bonenkamp, J.J.; Krieken, J.H.J.M. van; Nagengast, F.M.

    2004-01-01

    PURPOSE: Autosomal dominant hereditary diffuse gastric cancer (HDGC) is caused by germ-line E-cadherin (CDH1) gene mutations. Early detection of cancer in carriers is difficult because HDGC escapes endoscopic detection. We hypothesized that the glucose metabolism is enhanced in HDGC and that this ca

  14. Surface functionalization of inorganic nano-crystals with fibronectin and E-cadherin chimera synergistically accelerates trans-gene delivery into embryonic stem cells.

    Science.gov (United States)

    Kutsuzawa, K; Chowdhury, E H; Nagaoka, M; Maruyama, K; Akiyama, Y; Akaike, T

    2006-11-24

    Stem cells holding great promises in regenerative medicine have the potential to be differentiated to a specific cell type through genetic manipulation. However, conventional ways of gene transfer to such progenitor cells suffer from a number of disadvantages particularly involving safety and efficacy issues. Here, we report on the development of a bio-functionalized inorganic nano-carrier of DNA by embedding fibronectin and E-cadherin chimera on the carrier, leading to its high affinity interactions with embryonic stem cell surface and accelerated trans-gene delivery for subsequent expression. While only apatite nano-particles were very inefficient in transfecting embryonic stem cells, fibronectin-anchored particles and to a more significant extent, fibronectin and E-cadherin-Fc-associated particles dramatically enhanced trans-gene delivery with a value notably higher than that of commercially available lipofection system. The involvement of both cell surface integrin and E-cadherin in mediating intracellular localization of the hybrid carrier was verified by blocking integrin binding site with excess free fibronectin and up-regulating both integrin and E-cadherin through PKC activation. Thus, the new establishment of a bio-functional hybrid gene-carrier would promote and facilitate development of stem cell-based therapy in regenerative medicine.

  15. The contribution of TGF-β in Epithelial-Mesenchymal Transition (EMT): Down-regulation of E-cadherin via snail.

    Science.gov (United States)

    Yu, H; Shen, Y; Hong, J; Xia, Q; Zhou, F; Liu, X

    2015-01-01

    TGF-β plays a central role in epithelial-mesenchymal transition (EMT), which is a highly conserved and reversible process that governs tumor development, invasion and metastasis. Through this transition, the epithelial cell acquires a migratory behavior which allows it to move away from the cell community and to integrate into the surrounding tissue. The cells lost epithelial phenotypes including the change of cell polarity and the loss of specialized cell-cell contacts, which related with the shortage of E-cadherin directly. The increasing reports indicated that TGF-β down-regulated the expression of E-cadherin through snail signaling pathway, which played an important role in the development of EMT. In this review, we summarized the contribution of TGF-β in EMT and discussed the molecular mechanism of snail signaling participating in the regulation of E-cadherin triggered by TGF-β. TGF-β, Epithelial-mesenchymal-transition (EMT), snail family, E-cadherin.

  16. PTEN Loss in E-Cadherin-Deficient Mouse Mammary Epithelial Cells Rescues Apoptosis and Results in Development of Classical Invasive Lobular Carcinoma

    Directory of Open Access Journals (Sweden)

    Mirjam C. Boelens

    2016-08-01

    Full Text Available Invasive lobular carcinoma (ILC is an aggressive breast cancer subtype with poor response to chemotherapy. Besides loss of E-cadherin, a hallmark of ILC, genetic inactivation of PTEN is frequently observed in patients. Through concomitant Cre-mediated inactivation of E-cadherin and PTEN in mammary epithelium, we generated a mouse model of classical ILC (CLC, the main histological ILC subtype. While loss of E-cadherin induced cell dissemination and apoptosis, additional PTEN inactivation promoted cell survival and rapid formation of invasive mammary tumors that recapitulate the histological and molecular features, estrogen receptor (ER status, growth kinetics, metastatic behavior, and tumor microenvironment of human CLC. Combined inactivation of E-cadherin and PTEN is sufficient to cause CLC development. These CLCs showed significant tumor regression upon BEZ235-mediated inhibition of PI3K signaling. In summary, this mouse model provides important insights into CLC development and suggests inhibition of phosphatidylinositol 3-kinase (PI3K signaling as a potential therapeutic strategy for targeting CLC.

  17. Morphological adaptation and protein modulation of myotendinous junction following moderate aerobic training.

    Science.gov (United States)

    Curzi, Davide; Baldassarri, Valentina; De Matteis, Rita; Salamanna, Francesca; Bolotta, Alessandra; Frizziero, Antonio; Fini, Milena; Marini, Marina; Falcieri, Elisabetta

    2015-04-01

    Myotendinous junction is the muscle-tendon interface through which the contractile force can be transferred from myofibrils to the tendon extracellular matrix. At the ultrastructural level, aerobic training can modify the distal myotendinous junction of rat gastrocnemius, increasing the contact area between tissues. The aim of this work is to investigate the correlation between morphological changes and protein modulation of the myotendinous junction following moderate training. For this reason, talin, vinculin and type IV collagen amount and spatial distribution were investigated by immunohistochemistry and confocal microscopy. The images were then digitally analyzed by evaluating fluorescence intensity. Morphometric analysis revealed a significant increased thickening of muscle basal lamina in the trained group (53.1 ± 0.4 nm) with respect to the control group (43.9 ± 0.3 nm), and morphological observation showed the presence of an electron-dense area in the exercised muscles, close to the myotendinous junction. Protein concentrations appeared significantly increased in the trained group (talin +22.2%; vinculin +22.8% and type IV collagen +11.8%) with respect to the control group. Therefore, our findings suggest that moderate aerobic training induces/causes morphological changes at the myotendinous junction, correlated to the synthesis of structural proteins of the muscular basal lamina and of the cytoskeleton.

  18. Epithelial requirement for in vitro proliferation and xenograft growth and metastasis of MDA-MB-468 human breast cancer cells: oncogenic rather than tumor-suppressive role of E-cadherin.

    Science.gov (United States)

    Hugo, H J; Gunasinghe, N P A D; Hollier, B G; Tanaka, T; Blick, T; Toh, A; Hill, P; Gilles, C; Waltham, M; Thompson, E W

    2017-07-27

    Epithelial-to-mesenchymal transition (EMT) is associated with downregulated E-cadherin and frequently with decreased proliferation. Proliferation may be restored in secondary metastases by mesenchymal-to-epithelial transition (MET). We tested whether E-cadherin maintains epithelial proliferation in MDA-MB-468 breast cancer cells, facilitating metastatic colonization in severe combined immunodeficiency (SCID) mice. EMT/MET markers were assessed in xenograft tumors by immunohistochemistry. Stable E-cadherin manipulation was effected by transfection and verified by Western blotting, immunocytochemistry, and quantitative polymerase chain reaction (qPCR). Effects of E-cadherin manipulation on proliferation and chemomigration were assessed in vitro by performing sulforhodamine B assays and Transwell assays, respectively. Invasion was assessed by Matrigel outgrowth; growth in vivo was assessed in SCID mice; and EMT status was assessed by qPCR. Hypoxic response of E-cadherin knockdown cell lines was assessed by qPCR after hypoxic culture. Repeated measures analysis of variance (ANOVA), one- and two-way ANOVA with posttests, and paired Student's t tests were performed to determine significance (p MB-468 xenografts in regions of hypoxia. Extratumoral deposits (vascular and lymphatic inclusions, local and axillary nodes, and lung metastases) strongly expressed E-cadherin. MDA-MB-468 cells overexpressing E-cadherin were more proliferative and less migratory in vitro, whereas E-cadherin knockdown (short hairpin CDH1 [shCDH1]) cells were more migratory and invasive, less proliferative, and took longer to form tumors. shCDH1-MDA-MB-468 xenografts did not contain the hypoxia-induced necrotic areas observed in wild-type (WT) and shSCR-MDA-MB-468 tumors, but they did not exhibit an impaired hypoxic response in vitro. Although vimentin expression was not stimulated by E-cadherin knockdown in 2D or 3D cultures, xenografts of these cells were globally vimentin-positive rather than

  19. Side-stream smoking reduces intestinal inflammation and increases expression of tight junction proteins

    Institute of Scientific and Technical Information of China (English)

    Hui Wang; Jun-Xing Zhao; Nan Hu; Jun Ren; Min Du; Mei-Jun Zhu

    2012-01-01

    AIM:To investigate the effect of side-stream smoking on gut microflora composition,intestinal inflammation and expression of tight junction proteins.METHODS:C57BL/6 mice were exposed to side-stream cigarette smoking for one hour daily over eight weeks.Cecal contents were collected for microbial composition analysis.Large intestine was collected for immunoblotting and quantitative reverse transcriptase polymerase chain reaction analyses of the inflammatory pathway and tight junction proteins.RESULTS:Side-stream smoking induced significant changes in the gut microbiota with increased mouse intestinal bacteria,Clostridium but decreased Fermicutes (Lactoccoci and Ruminococcus),Enterobacteriaceae family and Segmented filamentous baceteria compared to the control mice.Meanwhile,side-stream smoking inhibited the nuclear factor-κB pathway with reduced phosphorylation of p65 and IκBα,accompanied with unchanged mRNA expression of tumor necrosis factor-α or interleukin-6.The contents of tight junction proteins,claudin3 and ZO2 were up-regulated in the large intestine of mice exposed side-stream smoking.In addition,side-stream smoking increased c-Jun N-terminal kinase and p38 MAPK kinase signaling,while inhibiting AMP-activated protein kinase in the large intestine.CONCLUSION:Side-stream smoking altered gut microflora composition and reduced the inflammatory response,which was associated with increased expression of tight junction proteins.

  20. Sulforaphane counteracts aggressiveness of pancreatic cancer driven by dysregulated Cx43-mediated gap junctional intercellular communication

    Science.gov (United States)

    Zhang, Yiyao; Isayev, Orkhan; Heilmann, Katharina; Schoensiegel, Frank; Liu, Li; Nessling, Michelle; Richter, Karsten; Labsch, Sabrina; Nwaeburu, Clifford C.; Mattern, Juergen; Gladkich, Jury; Giese, Nathalia; Werner, Jens; Schemmer, Peter; Gross, Wolfgang; Gebhard, Martha M.; Gerhauser, Clarissa; Schaefer, Michael; Herr, Ingrid

    2014-01-01

    The extreme aggressiveness of pancreatic ductal adenocarcinoma (PDA) has been associated with blocked gap junctional intercellular communication (GJIC) and the presence of cancer stem cells (CSCs). We examined whether disturbed GJIC is responsible for a CSC phenotype in established and primary cancer cells and patient tissue of PDA using interdisciplinary methods based in physiology, cell and molecular biology, histology and epigenetics. Flux of fluorescent dyes and gemcitabine through gap junctions (GJs) was intact in less aggressive cells but not in highly malignant cells with morphological dysfunctional GJs. Among several connexins, only Cx43 was expressed on the cell surface of less aggressive and GJIC-competent cells, whereas Cx43 surface expression was absent in highly malignant, E-cadherin-negative and GJIC-incompetent cells. The levels of total Cx43 protein and Cx43 phosphorylated at Ser368 and Ser279/282 were high in normal tissue but low to absent in malignant tissue. si-RNA-mediated inhibition of Cx43 expression in GJIC-competent cells prevented GJIC and induced colony formation and the expression of stem cell-related factors. The bioactive substance sulforaphane enhanced Cx43 and E-cadherin levels, inhibited the CSC markers c-Met and CD133, improved the functional morphology of GJs and enhanced GJIC. Sulforaphane altered the phosphorylation of several kinases and their substrates and inhibition of GSK3, JNK and PKC prevented sulforaphane-induced CX43 expression. The sulforaphane-mediated expression of Cx43 was not correlated with enhanced Cx43 RNA expression, acetylated histone binding and Cx43 promoter de-methylation, suggesting that posttranslational phosphorylation is the dominant regulatory mechanism. Together, the absence of Cx43 prevents GJIC and enhances aggressiveness, whereas sulforaphane counteracts this process, and our findings highlight dietary co-treatment as a viable treatment option for PDA. PMID:24742583

  1. Roles of neuro-exocytotic proteins at the neuromuscular junction

    NARCIS (Netherlands)

    Sons-Michel, Michèle S.

    2011-01-01

    The aim of the studies described in the thesis was to elucidate the roles of several neuro-exocytotic proteins at the motor nerve terminal in neuromuscular synaptic transmission, making use of genetic knockout (KO) mice, each missing one (or more) neuro-exocytotic proteins. In addition, it was

  2. Integrins stimulate E-cadherin-mediated intercellular adhesion by regulating Src-kinase activation and actomyosin contractility.

    Science.gov (United States)

    Martinez-Rico, Clara; Pincet, Frederic; Thiery, Jean-Paul; Dufour, Sylvie

    2010-03-01

    Cadherins and integrins are major adhesion molecules regulating cell-cell and cell-matrix interactions. In vitro and in vivo studies have demonstrated the existence of crosstalk between integrins and cadherins in cell adhesion and motility. We used a dual pipette assay to measure the force required to separate E-cadherin-producing cell doublets and to investigate the role of integrin in regulating the strength of intercellular adhesion. A greater force was required to separate cell doublets bound to fibronectin or vitronectin-coated beads than for doublets bound to polylysine-coated beads. This effect depended on cell spreading and the duration of stimulation. Cells expressing type II cadherin-7 also responded to fibronectin stimulation to produce a higher intercellular adhesion. Establishment of cadherin-mediated adhesion needed ROCK, MLCK and myosin ATPase II activity. The regulation of intercellular adhesion strength by integrin stimulation required activation of Src family kinases, ROCK and actomyosin contractility. These findings highlight the importance and mechanisms of molecular crosstalk between cadherins and integrins in the control of cell plasticity during histogenesis and morphogenesis.

  3. The -160C>a polymorphism in E-cadherin is associated with the risk of nephrolithiasis.

    Science.gov (United States)

    Tan, Mingyue; Xia, Shengqiang; Zhang, Qi; Zhu, Jiang; Bao, Erdun

    2013-01-01

    Nephrolithiasis is a common disorder worldwide. E-cadherin (CDH1) is involved in epithelial cell-cell interactions and plays important roles in the etiology of nephrolithiasis. We hypothesized that variants in the CDH1 gene are associated with risk of nephrolithiasis. In a hospital-based case-control study of 127 nephrolithiasis patients and 152 controls frequency matched by age and sex, we genotyped the functional -160C>A (rs16260) polymorphism and assessed its associations with risk of nephrolithiasis in a Chinese population. We found that the CA/AA genotypes were associated with a significantly decreased risk of nephrolithiasis (OR = 0.53, 95%CI = 0.32-0.87), compared with the CC genotype, particularly among subgroups of BMI > 24 kg/m(2) (OR = 0.38, 95%CI = 0.17-0.85), age ≤ 57 years (OR = 0.47, 95%CI = 0.24-0.93), and men (OR = 0.56, 95%CI = 0.29-0.99). Our results suggest that the CDH1 polymorphism is involved in the etiology of nephrolithiasis and thus may be a marker for genetic susceptibility to nephrolithiasis.

  4. Aberrant methylation of Glutathione S-transferase P1 and E-cadherin in invasive ductal breast carcinoma and fibroadenoma

    Institute of Scientific and Technical Information of China (English)

    Wings Tjing Yung Loo; Mary Ngan Bing Cheung; Louis Wing Cheong Chow

    2010-01-01

    Objective To investigate the hypermethylation status of glutathione transferase P1(GSTP1) and E cadherin (ECAD), TSGs (tumor suppressor genes) in our breast cancer samples and explore their correlation with clinicopathological features of corresponding cancer patients. Methods One hundred and thirty six IDC (invasive ductal carcinoma) patients were recruited for analysis and 16 fibroadenoma patients acted as control. DNA extraction and methylation specific PCR (MSP) were subsequently performed preceded by pathological examination. Results The percentage of hypermethylated GSTP1 in carcinoma and fibroadenoma groups was 34.92% and 15.79% respectively and the percentage of hypermethylated ECAD in carcinomas and fibroadenomas was 18.00% and 0.00% respectively. Carcinoma had the highest percentage of c erbB2 overexpression being 54.55% among the clinicopathological parameters. Conclusion Hypermethylation patterns are frequent in IDC and seem to relate to c erbB2 overexpression, and such epigenetic change should not be neglected in fibroadenoma. Tumor methylation status in cancer patients can be determined at early stage and it may be a reference for better treatment planning.

  5. Slit-Robo signaling induces malignant transformation through Hakai-mediated E-cadherin degradation during colorectal epithelial cell carcinogenesis

    Institute of Scientific and Technical Information of China (English)

    Wei-Jie Zhou; Yan-Qing Ding; Jian-Guo Geng; Zhen H Geng; Shan Chi; Wenli Zhang; Xiao-Feng Niu; Shu-Jue Lan; Li Ma; Xuesong Yang; Li-Jing Wang

    2011-01-01

    The Slit family of guidance cues binds to Roundabout (Robo) receptors and modulates cell migration. We report here that ectopic expression of Slit2 and Robol or recombinant Slit2 treatment of Robol-expressing colorectal epithelial carcinoma cells recruited an ubiquitin ligase Hakai for E-cadherin (E-cad) ubiquitination and lysosomal degradation, epithelial-mesenchymal transition (EMT), and tumor growth and liver metastasis, which were rescued by knockdown of Hakai. In contrast, knockdown of endogenous Robol or specific blockade of Slit2 binding to Robol prevented E-cad degradation and reversed EMT, resulting in diminished tumor growth and liver metastasis.Ectopic expression of Robol also triggered a malignant transformation in Siit2-positive human embryonic kidney 293 cells. Importantly, the expression of Slit2 and Robol was significantly associated with an increased metastatic risk and poorer overall survival in colorectal carcinoma patients. We conclude that engagement of Robol by Slit2 induces malignant transformation through Hakai-mediated E-cad ubiquitination and lysosomal degradation during colorectal epithelial cell carcinogenesis.

  6. Clinicopathological Significance of E-cadherin and PCNA Expression in Hunman Non-small Cell Lung Cancer

    Institute of Scientific and Technical Information of China (English)

    Jianwei Ma; Kai Fan; Yanli Zhang; Dawei Song; Jianmei Ma

    2008-01-01

    OBJECTIVE This study was designed to assess E-cadherin(E-cad) and proliferating cell nuclear antigen (PCNA) expression as well as their clinicopathological significance in hunman non-small cell lung cancers (NSCLCs). Possible molecular mechanisms of differentiation and metastasis of NSCLCs are discussed.METHODS Immunohistochemical and immunofluorescence double staining were performed to examine the expression of E-cad and PCNA in 68 primary NSCLCs cases.RESULTS The E-cad expression in squamous cell carcinomas and adenocarcinomas showed no significant difference. E-cad expression had a positive correlation with the histological-differentiated grade. A significant difference of Ecad expression was found between metastatic and non-metastatic groups. PCNA expression in squamous cell carcinomas and adenocarcinomas showed no significant difference. The PCNA expression had a reverse correlation with the histological-differentiated grade. A significant difference of PCNA expression was found between metastatic and non- metastatic groups. The E-cad and PCNA expression presented a reverse correlation.CONCLUSION E-cad expression is not associated with the histological type of NSCLC, but is associated with differentiation and metastasis of the cancer. Down-regulation of E-cad expression affects the proliferation of cancer cells. Conjoint analysis of E-cad and PCNA expression is a good way to evaluate tumor biological behavior.

  7. Interstitial fluid pressure regulates collective invasion in engineered human breast tumors via Snail, vimentin, and E-cadherin.

    Science.gov (United States)

    Piotrowski-Daspit, Alexandra S; Tien, Joe; Nelson, Celeste M

    2016-03-14

    Many solid tumors exhibit elevated interstitial fluid pressure (IFP). This elevated pressure within the core of the tumor results in outward flow of interstitial fluid to the tumor periphery. We previously found that the directionality of IFP gradients modulates collective invasion from the surface of patterned three-dimensional (3D) aggregates of MDA-MB-231 human breast cancer cells. Here, we used this 3D engineered tumor model to investigate the molecular mechanisms underlying IFP-induced changes in invasive phenotype. We found that IFP alters the expression of genes associated with epithelial-mesenchymal transition (EMT). Specifically, the levels of Snail, vimentin, and E-cadherin were increased under pressure conditions that promoted collective invasion. These changes in gene expression were sufficient to direct collective invasion in response to IFP. Furthermore, we found that IFP modulates the motility and persistence of individual cells within the aggregates, which are also influenced by the expression levels of EMT markers. Together, these data provide insight into the molecular mechanisms that guide collective invasion from primary tumors in response to IFP.

  8. Loss of CDH1 (E-cadherin) expression is associated with infiltrative tumour growth and lymph node metastasis.

    Science.gov (United States)

    Kim, Sun A; Inamura, Kentaro; Yamauchi, Mai; Nishihara, Reiko; Mima, Kosuke; Sukawa, Yasutaka; Li, Tingting; Yasunari, Mika; Morikawa, Teppei; Fitzgerald, Kathryn C; Fuchs, Charles S; Wu, Kana; Chan, Andrew T; Zhang, Xuehong; Ogino, Shuji; Qian, Zhi Rong

    2016-01-19

    Loss of CDH1 (E-cadherin) expression in cancer cells may promote cell migration and invasion. Therefore, we hypothesised that loss of CDH1 expression in colorectal carcinoma might be associated with aggressive features and clinical outcome. Utilising molecular pathological epidemiology database of 689 rectal and colon cancer cases in the Nurses' Health Study and the Health Professionals Follow-up Study, we assessed tumour CDH1 expression by immunohistochemistry. Multivariate logistic regression analysis was conducted to assess association of CDH1 loss with tumour growth pattern (expansile-intermediate vs infiltrative) and lymph node metastasis and distant metastasis, controlling for potential confounders including microsatellite instability, CpG island methylator phenotype, LINE-1 methylation, and PIK3CA, BRAF and KRAS mutations. Mortality according to CDH1 status was assessed using Cox proportional hazards model. Loss of tumour CDH1 expression was observed in 356 cases (52%), and associated with infiltrative tumour growth pattern (odds ratio (OR), 2.02; 95% confidence interval (CI), 1.23-3.34; P=0.006) and higher pN stage (OR, 1.73; 95% CI, 1.23-2.43; P=0.001). Tumour CDH1 expression was not significantly associated with distant metastasis or prognosis. Loss of CDH1 expression in colorectal cancer is associated with infiltrative tumour growth pattern and lymph node metastasis.

  9. West Nile virus infection causes endocytosis of a specific subset of tight junction membrane proteins.

    Directory of Open Access Journals (Sweden)

    Zaikun Xu

    Full Text Available West Nile virus (WNV is a blood-borne pathogen that causes systemic infections and serious neurological disease in human and animals. The most common route of infection is mosquito bites and therefore, the virus must cross a number of polarized cell layers to gain access to organ tissue and the central nervous system. Resistance to trans-cellular movement of macromolecules between epithelial and endothelial cells is mediated by tight junction complexes. While a number of recent studies have documented that WNV infection negatively impacts the barrier function of tight junctions, the intracellular mechanism by which this occurs is poorly understood. In the present study, we report that endocytosis of a subset of tight junction membrane proteins including claudin-1 and JAM-1 occurs in WNV infected epithelial and endothelial cells. This process, which ultimately results in lysosomal degradation of the proteins, is dependent on the GTPase dynamin and microtubule-based transport. Finally, infection of polarized cells with the related flavivirus, Dengue virus-2, did not result in significant loss of tight junction membrane proteins. These results suggest that neurotropic flaviviruses such as WNV modulate the host cell environment differently than hemorrhagic flaviviruses and thus may have implications for understanding the molecular basis for neuroinvasion.

  10. E-cadherin expression and bromodeoxyuridine incorporation during development of ovarian inclusion cysts in age-matched breeder and incessantly ovulated CD-1 mice

    Directory of Open Access Journals (Sweden)

    Beaugié Clare R

    2007-04-01

    Full Text Available Abstract Background Female CD-1/Swiss Webster mice subjected to incessant ovulation for 8 months and 12-month breeder mice both developed ovarian inclusion cysts similar to serous cystadenomas. The majority of cysts appeared to be dilated rete ovarii tubules, but high ovulation number resulted in more cortical inclusion cysts. We hypothesized that comparison of inclusion cyst pathology in animals of the same age, but with differences in total lifetime ovulation number, might allow us to determine distinguishing characteristics of the two types of cyst. Methods Ovaries from breeder mice (BR or females subjected to incessant ovulation (IO were compared at 6-, 9- and 12-months of age. Ovaries were serially sectioned and cysts characterized with regard to location and histology, E-cadherin immunoreactivity and rates of BrdU incorporation. Results Inclusion cysts developed with age in BR and IO ovaries. The majority of cysts were connected to the ovarian hilus. Two cortical inclusion cysts were observed in ten IO ovaries and one in ten BR ovaries. Low or no E-cadherin immuno-staining was seen in the OSE of all mice studied. Conversely, strong membrane immuno-staining was observed in rete ovarii epithelial cells. Variable E-cadherin immunoreactivity was seen in cells of hilar inclusion cysts, with strong staining observed in cuboidal ciliated cells and little or no staining in flat epithelial cells. Two of the three cortical cysts contained papillae, which showed E-cadherin immuno-staining at the edge of cells. However hilar and cortical cysts were not distinguishable by morphology, cell type or E-cadherin immunoreactivity. BrdU incorporation in cyst cells (1.4% [95% CI: 1.0 to 2.1] was greater than in OSE (0.7% [95% CI: 0.4 to 1.2] and very few BrdU-labeled cells were observed in rete ovarii at any age. Incessant ovulation significantly increased BrdU incorporation in OSE of older animals. Conclusion These experiments confirm ovarian inclusion cysts

  11. The gap junction protein connexin43 interacts with the second PDZ domain of the zona occludens-1 protein

    NARCIS (Netherlands)

    Giepmans, B N; Moolenaar, W H

    1998-01-01

    Gap junctions mediate cell-cell communication in almost all tissues and are composed of channel-forming integral membrane proteins, termed connexins [1-3]. Connexin43 (Cx43) is the most widely expressed and the most well-studied member of this family. Cx43-based cell-cell communication is regulated

  12. Targeting Holliday junctions by origin DNA-binding protein of herpes simplex virus type 1.

    Science.gov (United States)

    Moiseeva, E D; Bazhulina, N P; Gursky, Y G; Grokhovsky, S L; Surovaya, A N; Gursky, G V

    2017-03-01

    In the present paper, the interactions of the origin binding protein (OBP) of herpes simplex virus type 1 (HSV1) with synthetic four-way Holliday junctions (HJs) were studied using electrophoresis mobility shift assay and the FRET method and compared with the interactions of the protein with duplex and single-stranded DNAs. It has been found that OBP exhibits a strong preference for binding to four-way and three-way DNA junctions and possesses much lower affinities to duplex and single-stranded DNAs. The protein forms three types of complexes with HJs. It forms complexes I and II which are reminiscent of the tetramer and octamer complexes with four-way junction of HJ-specific protein RuvA of Escherichia coli. The binding approaches saturation level when two OBP dimers are bound per junction. In the presence of Mg(2+) ions (≥2 mM) OBP also interacts with HJ in the stacked arm form (complex III). In the presence of 5 mM ATP and 10 mM Mg(2+) ions OBP catalyzes processing of the HJ in which one of the annealed oligonucleotides has a 3'-terminal tail containing 20 unpaired thymine residues. The observed preference of OBP for binding to the four-way DNA junctions provides a basis for suggestion that OBP induces large DNA structural changes upon binding to Box I and Box II sites in OriS. These changes involve the bending and partial melting of the DNA at A+T-rich spacer and also include the formation of HJ containing Box I and Box II inverted repeats and flanking DNA sequences.

  13. Interaction of HMG proteins and H1 with hybrid PNA-DNA junctions.

    Science.gov (United States)

    Totsingan, Filbert; Bell, Anthony J

    2013-11-01

    The objective of this study was to evaluate the effects of inserting peptide nucleic acid (PNA) sequences into the protein-binding surface of an immobilized four-way junction (4WJ). Here we compare the classic immobile DNA junction, J1, with two PNA containing hybrid junctions (4WJ-PNA1 and 4WJ-PNA3 ). The protein interactions of each 4WJ were evaluated using recombinant high mobility group proteins from rat (HMGB1b and HMGB1b/R26A) and human histone H1. In vitro studies show that both HMG and H1 proteins display high binding affinity toward 4WJ's. A 4WJ can access different conformations depending on ionic environment, most simply interpreted by a two-state equilibrium between: (i) an open-x state favored by absence of Mg(2+), low salt, and protein binding, and (ii) a compact stacked-x state favored by Mg(2+). 4WJ-PNA3, like J1, shifts readily from an open to stacked conformation in the presence of Mg(+2), while 4WJ-PNA1 does not. Circular dichroism spectra indicate that HMGB1b recognizes each of the hybrid junctions. H1, however, displays a strong preference for J1 relative to the hybrids. More extensive binding analysis revealed that HMGB1b binds J1 and 4WJ-PNA3 with nearly identical affinity (K(D)s) and 4WJ-PNA1 with two-fold lower affinity. Thus both the sequence/location of the PNA sequence and the protein determine the structural and protein recognition properties of 4WJs.

  14. Lateral self-assembly of E-cadherin directed by cooperative calcium binding.

    Science.gov (United States)

    Alattia, J R; Ames, J B; Porumb, T; Tong, K I; Heng, Y M; Ottensmeyer, P; Kay, C M; Ikura, M

    1997-11-17

    We report the Ca2+ binding characteristics of recombinant Ecad12, a construct spanning the first two repeats of epithelial cadherin, and demonstrate the links between Ca2+ binding and dimer formation. Sedimentation equilibrium and dynamic light scattering experiments show that weak dimerization of Ecad12 occurs in the presence of 10 mM Ca2+ (KdP = 0.17 mM), while no appreciable dimer formation was detected in the absence of Ca2+. Ca2+-induced dimerization was also observed in electron microscopy images of Ecad12. We conclude from Ca2+ titration experiments monitored by tryptophan fluorescence and flow dialysis that dimerization does not affect the equilibrium binding constant for Ca2+. However, the value of the Hill coefficient for Ca2+ binding increases from 1.5 to 2.4 as the protein concentration increases, showing that dimer formation largely contributes to the cooperativity in Ca2+ binding. Based on these observations and previous crystallographic studies, we propose that calcium acts more likely as a geometrical aligner ensuring the proper assembly of cadherin molecules, rather than a simple adhesive.

  15. Snail与E-钙粘素甲基化协同抑制E-钙粘素的表达%The Inhibitory Effect of Snail and E-cadherin Methylation Synergistically on E-cadherin Expression

    Institute of Scientific and Technical Information of China (English)

    高羽; 刘庆彤; 王源; 师水生

    2013-01-01

    目的 探讨去甲基化药物5-氮杂-2’-脱氧胞苷(简称5-Aza)对转录调节因子Snail的作用,转染反义Snail与5-Aza对上皮间质转化相关膜蛋白E-钙粘素的mRNA水平的影响及二者联合作用的可能机制.方法 应用MTT、PCR、实时荧光定量PCR、检测低分化胃腺癌细胞株分别转染反义Snail、应用5-Aza单独或协同干预后对细胞的生长增殖及Snail、E-钙粘素mRNA表达的影响.结果 与空白对照组比较5-Aza干预、转染反义Snail分别及二者共同干预均增加E-cadherin的mRNA 的表达,空质粒组无显著差异.5-Aza上调Snail基因mRNA的表达.两种干预方式处理均能抑制胃癌细胞的生长.结论 5-Aza、转染反义Snail均使E-cadherin mRNA表达增强,且药物作用呈时间浓度依赖性.5-Aza能上调Snail基因的表达,提示甲基化作用在同时下调转录调节子Snail基因表达和抑制E-钙粘素表达.

  16. Grainy head promotes expression of septate junction proteins and influences epithelial morphogenesis.

    Science.gov (United States)

    Narasimha, Maithreyi; Uv, Anne; Krejci, Alena; Brown, Nicholas H; Bray, Sarah J

    2008-03-15

    Transcription factors of the Grainy head (Grh) family are required in epithelia to generate the impermeable apical layer that protects against the external environment. This function is conserved in vertebrates and invertebrates, despite the differing molecular composition of the protective barrier. Epithelial cells also have junctions that create a paracellular diffusion barrier (tight or septate junctions). To examine whether Grh has a role in regulating such characteristics, we used an epidermal layer in the Drosophila embryo that has no endogenous Grh and lacks septate junctions, the amnioserosa. Expression of Grh in the amnioserosa caused severe defects in dorsal closure, a process similar to wound closure, and induced robust expression of the septate junction proteins Coracle, Fasciclin 3 and Sinuous. Grh-binding sites are present within the genes encoding these proteins, consistent with them being direct targets. Removal of Grh from imaginal disc cells caused a reduction in Fasciclin 3 and Coracle levels, suggesting that Grh normally fine tunes their epithelial expression and hence contributes to barrier properties. The fact that ectopic Grh arrests dorsal closure also suggests that this dynamic process relies on epithelia having distinct adhesive properties conferred by differential deployment of Grh.

  17. Effects of carbon dioxide and nitrogen on adhesive growth and expressions of E-cadherin and VEGF of human colon cancer cell CCL-228

    Institute of Scientific and Technical Information of China (English)

    Kai-Lin Cai; Guo-Bing Wang; Li-Juan Xiong

    2003-01-01

    AIM: To study the effects of carbon dioxide on the metastatic capability of cancer cells, and to compare them with that of nitrogen.METHODS: The colon cancer cell CCL-228 was treated with 100 % carbon dioxide or nitrogen at different time points and then cultured under normal condition. Twelve hours after the treatment, the survival rates of suspension cells and the expressions of e-cadherin and VEGF were examined.RESULTS: After 60 min of carbon dioxide and longer time of nitrogen treatment, the suspended cells increased and the expression of e-cadherin decreased while the expression of VEGF was enhanced significantly. And the effects of nitrogen were similar to, but weaker than, those of carbon dioxide.CONCLUSION: Carbon dioxide may improve the metastatic capability of cancer cells and its effects are significantly stronger than that of nitrogen. A sequential use of carbon dioxide and nitrogen in pneumoperitoneum may take the advantage of both gases.

  18. Rapid paracellular transmigration of Campylobacter jejuni across polarized epithelial cells without affecting TER: role of proteolytic-active HtrA cleaving E-cadherin but not fibronectin

    LENUS (Irish Health Repository)

    Boehm, Manja

    2012-04-25

    AbstractBackgroundCampylobacter jejuni is one of the most important bacterial pathogens causing food-borne illness worldwide. Crossing the intestinal epithelial barrier and host cell entry by C. jejuni is considered the primary reason of damage to the intestinal tissue, but the molecular mechanisms as well as major bacterial and host cell factors involved in this process are still widely unclear.ResultsIn the present study, we characterized the serine protease HtrA (high-temperature requirement A) of C. jejuni as a secreted virulence factor with important proteolytic functions. Infection studies and in vitro cleavage assays showed that C. jejuni’s HtrA triggers shedding of the extracellular E-cadherin NTF domain (90 kDa) of non-polarised INT-407 and polarized MKN-28 epithelial cells, but fibronectin was not cleaved as seen for H. pylori’s HtrA. Deletion of the htrA gene in C. jejuni or expression of a protease-deficient S197A point mutant did not lead to loss of flagella or reduced bacterial motility, but led to severe defects in E-cadherin cleavage and transmigration of the bacteria across polarized MKN-28 cell layers. Unlike other highly invasive pathogens, transmigration across polarized cells by wild-type C. jejuni is highly efficient and is achieved within a few minutes of infection. Interestingly, E-cadherin cleavage by C. jejuni occurs in a limited fashion and transmigration required the intact flagella as well as HtrA protease activity, but does not reduce transepithelial electrical resistance (TER) as seen with Salmonella, Shigella, Listeria or Neisseria.ConclusionThese results suggest that HtrA-mediated E-cadherin cleavage is involved in rapid crossing of the epithelial barrier by C. jejuni via a very specific mechanism using the paracellular route to reach basolateral surfaces, but does not cleave the fibronectin receptor which is necessary for cell entry.

  19. mRNA expression of adipocytokines and glucocorticoid-related genes are associated with downregulation of E-cadherin mRNA in colorectal adenocarcinomas.

    Science.gov (United States)

    Størkson, Ragnhild H; Aamodt, Rolf; Vetvik, Katja Kannisto; Pietilainen, Kirsi; Bukholm, Geir; Jonsdottir, Kristin; Vollan, Hilde S; Sonerud, Tonje; Lüders, Torben; Jacobsen, Morten B; Bukholm, Ida R K

    2012-08-01

    There is a consistently reported relationship between the incidence of colon cancer and obesity. It is thought that adipose tissue, particularly visceral fat, which secretes systemic factors that alter immunological, metabolic and endocrine milieu and promotes insulin resistance by producing adipocytokines, is important in cancer progression. Systemic high concentrations of adipocytokines, such as tumour necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6), and glucocorticoid metabolism-related genes have been associated with gastrointestinal cancer. However, limited information exists about the expression of these cytokines within tumour tissue. mRNA expression of TNF-α, IL-6,IL-8, IL-10, IL-1RN, glucocorticoid receptor alpha (GR-α), 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1), plasminogen activator inhibitor-1 (PAI-1), Slug, vimentin, Snail and E-cadherin was analysed in paired samples of tumour tissue and normal mucosa in 60 surgical patients for Dukes B and C colorectal adenocarcinomas using quantitative reverse transcription PCR and microarray technology. The mRNA expression level of analysed genes was compared between tumour tissue and normal mucosa from the same patients, and a correlation to mRNA expression of E-cadherin in the same tissue samples was also performed. A highly significant difference in mRNA expression level of several of the analysed genes was observed between tumour tissue and the normal intestinal mucosa. Inverse correlation between mRNA expression of 11βHSD1, IL-6, GR-α and PAI-1 on one hand and mRNA expression of E-cadherin on the other hand was observed. Results show that the adipocytokines and glucocorticoid metabolism-related genes are overexpressed in colorectal adenocarcinomas, and expression of these genes is associated with the downregulation of E-cadherin mRNA, connecting these genes to carcinogenesis and progression of colorectal cancer.

  20. EGFR, p16INK4a and E-cadherin immuno-histochemistry and EGFR point mutations analyses in invasive cervical cancer specimens from Moroccan women.

    OpenAIRE

    El Hamdani, W.; M. Amrani; Attaleb, M.; Laantri, N.; Ennaji, M. M.; Khyatti, M.; El Mzibri, M.

    2010-01-01

    The involvement of human papillomavirus in the development of cervical cancer has been firmly established. However, better management of cervical cancer rests on good diagnosis and an effective therapy. In this study we evaluated the frequency of point mutations in epidermal growth factor receptor (EGFR) for future use of tyrosine kinase inhibitors in clinical treatment and to assess the use of EGFR, p16INK4a and E-cadherin as biomarkers in cervical cancer diagnosis with immunohistochemistry....

  1. Identification of MarvelD3 as a tight junction-associated transmembrane protein of the occludin family

    Directory of Open Access Journals (Sweden)

    Balda Maria S

    2009-12-01

    Full Text Available Abstract Background Tight junctions are an intercellular adhesion complex of epithelial and endothelial cells, and form a paracellular barrier that restricts the diffusion of solutes on the basis of size and charge. Tight junctions are formed by multiprotein complexes containing cytosolic and transmembrane proteins. How these components work together to form functional tight junctions is still not well understood and will require a complete understanding of the molecular composition of the junction. Results Here we identify a new transmembrane component of tight junctions: MarvelD3, a four-span transmembrane protein. Its predicted transmembrane helices form a Marvel (MAL and related proteins for vesicle traffic and membrane link domain, a structural motif originally discovered in proteins involved in membrane apposition and fusion events, such as the tight junction proteins occludin and tricellulin. In mammals, MarvelD3 is expressed as two alternatively spliced isoforms. Both isoforms exhibit a broad tissue distribution and are expressed by different types of epithelial as well as endothelial cells. MarvelD3 co-localises with occludin at tight junctions in intestinal and corneal epithelial cells. RNA interference experiments in Caco-2 cells indicate that normal MarvelD3 expression is not required for the formation of functional tight junctions but depletion results in monolayers with increased transepithelial electrical resistance. Conclusions Our data indicate that MarvelD3 is a third member of the tight junction-associated occludin family of transmembrane proteins. Similar to occludin, normal expression of MarvelD3 is not essential for the formation of functional tight junctions. However, MarvelD3 functions as a determinant of epithelial paracellular permeability properties.

  2. Gap junction proteins: master regulators of the planarian stem cell response to tissue maintenance and injury.

    Science.gov (United States)

    Peiris, T Harshani; Oviedo, Néstor J

    2013-01-01

    Gap junction (GJ) proteins are crucial mediators of cell-cell communication during embryogenesis, tissue regeneration and disease. GJ proteins form plasma membrane channels that facilitate passage of small molecules across cells and modulate signaling pathways and cellular behavior in different tissues. These properties have been conserved throughout evolution, and in most invertebrates GJ proteins are known as innexins. Despite their critical relevance for physiology and disease, the mechanisms by which GJ proteins modulate cell behavior are poorly understood. This review summarizes findings from recent work that uses planarian flatworms as a paradigm to analyze GJ proteins in the complexity of the whole organism. The planarian model allows access to a large pool of adult somatic stem cells (known as neoblasts) that support physiological cell turnover and tissue regeneration. Innexin proteins are present in planarians and play a fundamental role in controlling neoblast behavior. We discuss the possibility that GJ proteins participate as cellular sensors that inform neoblasts about local and systemic physiological demands. We believe that functional analyses of GJ proteins will bring a complementary perspective to studies that focus on the temporal expression of genes. Finally, integrating functional studies along with molecular genetics and epigenetic approaches would expand our understanding of cellular regulation in vivo and greatly enhance the possibilities for rationally modulating stem cell behavior in their natural environment. This article is part of a Special Issue entitled: The communicating junctions, roles and dysfunctions. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. mTrop1/Epcam knockout mice develop congenital tufting enteropathy through dysregulation of intestinal E-cadherin/β-catenin.

    Directory of Open Access Journals (Sweden)

    Emanuela Guerra

    Full Text Available Congenital tufting enteropathy (CTE is a life-threatening hereditary disease that is characterized by enteric mucosa tufting degeneration and early onset, severe diarrhea. Loss-of-function mutations of the human EPCAM gene (TROP1, TACSTD1 have been indicated as the cause of CTE. However, loss of mTrop1/Epcam in mice appeared to lead to death in utero, due to placental malformation. This and indications of residual Trop-1/EpCAM expression in cases of CTE cast doubt on the role of mTrop1/Epcam in this disease. The aim of this study was to determine the role of TROP1/EPCAM in CTE and to generate an animal model of this disease for molecular investigation and therapy development. Using a rigorous gene-trapping approach, we obtained mTrop1/Epcam -null (knockout mice. These were born alive, but failed to thrive, and died soon after birth because of hemorrhagic diarrhea. The intestine from the mTrop1/Epcam knockout mice showed intestinal tufts, villous atrophy and colon crypt hyperplasia, as in human CTE. No structural defects were detected in other organs. These results are consistent with TROP1/EPCAM loss being the cause of CTE, thus providing a viable animal model for this disease, and a benchmark for its pathogenetic course. In the affected enteric mucosa, E-cadherin and β-catenin were shown to be dysregulated, leading to disorganized transition from crypts to villi, with progressive loss of membrane localization and increasing intracellular accumulation, thus unraveling an essential role for Trop-1/EpCAM in the maintenance of intestinal architecture and functionality.Supporting information is available for this article.

  4. E-cadherin-dependent stimulation of traction force at focal adhesions via the Src and PI3K signaling pathways.

    Science.gov (United States)

    Jasaitis, Audrius; Estevez, Maruxa; Heysch, Julie; Ladoux, Benoit; Dufour, Sylvie

    2012-07-18

    The interplay between cadherin- and integrin-dependent signals controls cell behavior, but the precise mechanisms that regulate the strength of adhesion to the extracellular matrix remains poorly understood. We deposited cells expressing a defined repertoire of cadherins and integrins on fibronectin (FN)-coated polyacrylamide gels (FN-PAG) and on FN-coated pillars used as a micro-force sensor array (μFSA), and analyzed the functional relationship between these adhesion receptors to determine how it regulates cell traction force. We found that cadherin-mediated adhesion stimulated cell spreading on FN-PAG, and this was modulated by the substrate stiffness. We compared S180 cells with cells stably expressing different cadherins on μFSA and found that traction forces were stronger in cells expressing cadherins than in parental cells. E-cadherin-mediated contact and mechanical coupling between cells are required for this increase in cell-FN traction force, which was not observed in isolated cells, and required Src and PI3K activities. Traction forces were stronger in cells expressing type I cadherins than in cells expressing type II cadherins, which correlates with our previous observation of a higher intercellular adhesion strength developed by type I compared with type II cadherins. Our results reveal one of the mechanisms whereby molecular cross talk between cadherins and integrins upregulates traction forces at cell-FN adhesion sites, and thus provide additional insight into the molecular control of cell behavior. Copyright © 2012 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  5. 黏液素和上皮钙黏附蛋白在子宫内膜癌中的表达及其临床意义%Expression of MUC1 and E-cadherin in Endometrial Carcinomas and its Clinical Significance

    Institute of Scientific and Technical Information of China (English)

    赵时梅; 卓建红; 张安文; 韦毓; 罗宇; 史琳; 任传伟

    2011-01-01

    Objective To investigate the expression and clinical significance of MUC1 and E-cadherin in the pathologenesis of endometrial adenocarcinoma. Methods The expression levels of MUC1 and E-cadherin protein in endometrial adeno-carcinomas ( n = 55 ), endometrial atypical hyperplasia ( n = 50 ), endometrial hyperplasia ( n = 36 ) and normal proliferative endometrium ( n = 30 ) were examined by immunohistochemistry ( Envision method ). Results The normal positive rates of both MUC1 and E-cadherin protein were gradually reduced in normal proliferative endometrium, endometrial hyperplasia, endometrial atypical hyperplasia and endometrial adenocarcinomas ( P = 0.000 ). The normal positive rates of MUC1 protein was related to the age( P = 0.044 ),but it was not related to histological grade( P = 0. 678 ). The normal positive rates of E-cadherin protein was not associated with the age and the histological grade( P =0. 610,P = 0. 125 ). The expression of MUC1 protein was positive related to that of E-cadherin in endometrial adenocarcinomas( P =0. 0317 ). Conclusion The abnormal express of MUC1 protein and Ecadherin was involved in the development of endometrial adenocarcinomas, which has certain significance to the endometrium cancer' s diagnosis.%目的 探讨MUC1和E-cadherin在增生期子宫内膜、子宫内膜单纯性增生、子宫内膜不典型性增生和子宫内膜样腺癌组织中的表达及意义.方法 采用免疫组化Envision法检测30例增生期子宫内膜组织、36例单纯性增生内膜、50例不典型增生内膜及55例子宫内膜样腺癌组织中MUC1和E-cadherin蛋白表达.结果 从增生期子宫内膜-宫内膜单纯性增生-宫内膜不典型增生-子宫内膜样腺癌,MUC1和E-cadherin的正常表达率逐渐降低,异质表达率逐渐升高(P=0.000).MUC1蛋白表达与年龄有一定关系(P=0.044)、与组织学分级无关(P=0.678).E-cadherin 蛋白表达与年龄变化及组织学分级无关(P=0.610,P=0.125).MUC1和E-cadherin

  6. The Ly6 protein coiled is required for septate junction and blood brain barrier organisation in Drosophila.

    Directory of Open Access Journals (Sweden)

    Assia Hijazi

    Full Text Available BACKGROUND: Genetic analysis of the Drosophila septate junctions has greatly contributed to our understanding of the mechanisms controlling the assembly of these adhesion structures, which bear strong similarities with the vertebrate tight junctions and the paranodal septate junctions. These adhesion complexes share conserved molecular components and have a common function: the formation of paracellular barriers restraining the diffusion of solutes through epithelial and glial envelopes. METHODOLOGY/PRINCIPAL FINDINGS: In this work we characterise the function of the Drosophila cold gene, that codes for a protein belonging to the Ly6 superfamily of extracellular ligands. Analysis of cold mutants shows that this gene is specifically required for the organisation of the septate junctions in epithelial tissues and in the nervous system, where its contribution is essential for the maintenance of the blood-brain barrier. We show that cold acts in a cell autonomous way, and we present evidence indicating that this protein could act as a septate junction component. CONCLUSION/SIGNIFICANCE: We discuss the specific roles of cold and three other Drosophila members of the Ly6 superfamily that have been shown to participate in a non-redundant way in the process of septate junction assembly. We propose that vertebrate Ly6 proteins could fulfill analogous roles in tight junctions and/or paranodal septate junctions.

  7. SynProt: A Comprehensive Database for Proteins of the Detergent-Resistant Synaptic Junctions Fraction

    Directory of Open Access Journals (Sweden)

    Rainer ePielot

    2012-06-01

    Full Text Available Chemical synapses are highly specialized cell-cell contacts for communication between neurons in the CNS characterized by complex and dynamic protein networks at both synaptic membranes. The cytomatrix at the active zone (CAZ organizes the apparatus for the regulated release of transmitters from the presynapse. At the postsynaptic side, the postsynaptic density constitutes the machinery for detection, integration and transduction of the transmitter signal. Both pre- and postsynaptic protein networks represent the molecular substrates for synaptic plasticity. Their function can be altered both by regulating their composition and by post-translational modification of their components. For a comprehensive understanding of synaptic networks the entire ensemble of synaptic proteins has to be considered. To support this, we established a comprehensive database for synaptic junction proteins (SynProt database primarily based on proteomics data obtained from biochemical preparations of detergent-resistant synaptic junctions. The database currently contains 2,788 non-redundant entries of rat, mouse and some human proteins, which mainly have been manually extracted from twelve proteomic studies and annotated for synaptic subcellular localization. Each dataset is completed with manually added information including protein classifiers as well as automatically retrieved and updated information from public databases (UniProt and PubMed. We intend that the database will be used to support modeling of synaptic protein networks and rational experimental design.

  8. Resolution of Holliday junction recombination intermediates by wild-type and mutant IntDOT proteins.

    Science.gov (United States)

    Kim, Seyeun; Gardner, Jeffrey F

    2011-03-01

    CTnDOT encodes an integrase that is a member of the tyrosine recombinase family. The recombination reaction proceeds by sequential sets of genetic exchanges between the attDOT site in CTnDOT and an attB site in the chromosome. The exchanges are separated by 7 base pairs in each site. Unlike most tyrosine recombinases, IntDOT exchanges sites that contain different DNA sequences between the exchange sites to generate Holliday junctions (HJs) that contain mismatched bases. We demonstrate that IntDOT resolves synthetic HJs in vitro. Holliday junctions that contain identical sequences between the exchange sites are resolved into both substrates and products, while HJs that contain mismatches are resolved only to substrates. This result implies that resolution of HJs to products requires the formation of a higher-order nucleoprotein complex with natural sites containing IntDOT. We also found that proteins with substitutions of residues (V95, K94, and K96) in a putative alpha helix at the junction of the N and CB domains (coupler region) were defective in resolving HJs. Mutational analysis of charged residues in the coupler and the N terminus of the protein did not provide evidence for a charge interaction between the regions of the protein. V95 may participate in a hydrophobic interaction with another region of IntDOT.

  9. Effect of salvianolate on intestinal epithelium tight junction protein zonula occludens protein 1 in cirrhotic rats

    Institute of Scientific and Technical Information of China (English)

    Dan-Hong Yang; Zai-Yuan Ye; Yuan-Jun Xie; Xu-Jun He; Wen-Juan Xu; Wei-Ming Zhou

    2012-01-01

    AIM:To study the effect of salvianolate on tight junctions (TJs) and zonula occludens protein 1 (ZO-1) in small intestinal mucosa of cirrhotic rats.METHODS:Cirrhosis was induced using carbon tetrachloride.Rats were randomly divided into the untreated group,low-dose salvianolate (12 mg/kg) treatment group,medium-dose salvianolate (24 mg/kg) treatment group,and high-dose salvianolate (48 mg/kg) treatment group,and were treated for 2 wk.Another 10 healthy rats served as the normal control group.Histological changes in liver tissue samples were observed under a light microscope.We evaluated morphologic indices of ileal mucosa including intestinal villi width and thickness of mucosa and intestinal wall using a pathological image analysis system.Ultrastructural changes in small intestinal mucosa were investigated in the five groups using transmission electron microscopy.The changes in ZO-1 expression,a tight junction protein,were analyzed by immunocytochemistry.The staining index was calculated as the product of the staining intensity score and the proportion of positive cells.RESULTS:In the untreated group,hepatocytes showed a disordered arrangement,fatty degeneration was extensive,swelling was obvious,and disorganized lobules were divided by collagen fibers in hepatic tissue,which were partly improved in the salvianolate treated groups.In the untreated group,abundant lymphocytes infiltrated the fibrous tissue with proliferation of bile ducts,and collagen fibers gradually decreased and damaged hepatic lobules were partly repaired following salvianolate treatment.Compared with the untreated group,no differences in intestinal villi width between the five groups were observed.The villi height as well as mucosa and intestinal wall thickness gradually thickened with salvianolate treatment and were significantly shorter in the untreated group compared with those in the salvianolate treatment groups and normal group (P < 0.01).The number of microvilli decreased and showed

  10. Association of the Germline Mutations of E-Cadherin Gene ( CDH1 ) in Gastric Cancer%E-Cadherin(CDH1)基因胚系突变与胃癌风险的研究

    Institute of Scientific and Technical Information of China (English)

    张元颖; 李金田; 朱明; 张晓梅; 吴晓柳; 王亚平

    2005-01-01

    背景与目的:检测E-Cadherin(CDH1)基因在家族性胃癌中的突变情况以探讨CDH1基因胚系突变在家族性胃癌中的作用.方法:采用聚合酶链反应(Polymerase chain reaction,PCR)、变性高效液相色谱分析(Denaturing high-performance liquidschromatography,DHPLC)和直接测序法对CDH1基因进行全基因筛查,检查80名胃癌患者的CDH1基因突变情况,其中62例有家族史.同时检测80例正常人CDH1基因,进行分析比较.结果:2.5%(2/80)的胃癌患者检出CDH1基因错义突变Thr340Ala(杂合型),在80例正常人中未检出这一突变;第13外显子上游(内含子)第13位碱基检出多态位点IVS(13)-13T→C,这一多态性存在于12.5%(10/80)的胃癌患者和15.0%(12/80)的正常对照,两组差异无统计学意义;23.8%(19/80)的胃癌患者中检出同义突变Asn751Asn,相同的突变存在于8.8%(7/80)的正常对照.统计结果表明,胃癌患者中CDH1基因Asn751Asn检出率高于正常人群(P<0.05),这种差异主要表现在高年龄组胃癌患者(P<0.01).结论:CDH1基因胚系突变在家族性胃癌中不是频发事件,但多态位点Asn751Asn的存在可使携带者胃癌发病风险增高,可能是部分癌高发家族癌症发生的原因之一.

  11. Antofine-induced connexin43 gap junction disassembly in rat astrocytes involves protein kinase Cβ.

    Science.gov (United States)

    Huang, Yu-Fang; Liao, Chih-Kai; Lin, Jau-Chen; Jow, Guey-Mei; Wang, Hwai-Shi; Wu, Jiahn-Chun

    2013-03-01

    Antofine, a phenanthroindolizidine alkaloid derived from Cryptocaryachinensis and Ficusseptica in the Asclepiadaceae milkweed family, is cytotoxic for various cancer cell lines. In this study, we demonstrated that treatment of rat primary astrocytes with antofine induced dose-dependent inhibition of gap junction intercellular communication (GJIC), as assessed by scrape-loading 6-carboxyfluorescein dye transfer. Levels of Cx43 protein were also decreased in a dose- and time-dependent manner following antofine treatment. Double-labeling immunofluorescence microscopy showed that antofine (10ng/ml) induced endocytosis of surface gap junctions into the cytoplasm, where Cx43 was co-localized with the early endosome marker EEA1. Inhibition of lysosomes or proteasomes by co-treatment with antofine and their respective specific inhibitors, NH4Cl or MG132, partially inhibited the antofine-induced decrease in Cx43 protein levels, but did not inhibit the antofine-induced inhibition of GJIC. After 30min of treatment, antofine induced a rapid increase in the intracellular Ca(2+) concentration and activation of protein kinase C (PKC)α/βII, which was maintained for at least 6h. Co-treatment of astrocytes with antofine and the intracellular Ca(2+) chelator BAPTA-AM prevented downregulation of Cx43 and inhibition of GJIC. Moreover, co-treatment with antofine and a specific PKCβ inhibitor prevented endocytosis of gap junctions, downregulation of Cx43, and inhibition of GJIC. Taken together, these findings indicate that antofine induces Cx43 gap junction disassembly by the PKCβ signaling pathway. Inhibition of GJIC by antofine may undermine the neuroprotective effect of astrocytes in CNS.

  12. The study of the expression of E-cadherin and Snail in the labial glands of the patients with primary Sj(o)gren's syndrome%上皮型钙黏附蛋白和Snail在原发性干燥综合征患者唇腺组织中表达的相关研究

    Institute of Scientific and Technical Information of China (English)

    侯西倩; 竺红

    2013-01-01

    Objective To study the expression of E-cadherin protein and Snail protein in the labial glands of patients with primary Sj(o)gren's syndrome(pSS) and to analyze their roles in the pathogenesis of pSS.Methods The expression of E-cadherin protein and Snail protein were detected by immunohistochemical method.The labial glands were obtained from 50 patients with pSS and 30 healthy controls.The data was analyzed by Chi-Square test,Fisher's exact probability and Spearman's rank correlation analysis.Results The expression rate of E-cadherin in the labials gland of the patients with pSS were lower than that in normal salivary tissues (x2=14.651,P<0.01).The positive rates of Snail in the labial glands of the patients with PSS were 40% and it's expression rates were significantly higher than those in normal salivary tissues (x2=28.800,P<0.01).There was a negative correlation between lymphocyte focus score and the expression of E-cadherin (P<0.01) and a positive correlation between lymphocyte focus score and the expression of Snail in pSS group (P<0.01).There was a negative correlation between the expression of E-cadherin and Snail (rs=-0.484,P<0.01).Conclusion The interaction of E-cadherin and Snail may have played an important role in the pathogenesis of PSS.%目的 探讨锌指转录因子Snail、上皮型钙黏附蛋白(E-cad)在原发性干燥综合征(pSS)发病过程中的作用和意义.方法 采用免疫组织化学链霉素抗生物素-过氧化酶法(SP法)检测50例pSS患者及30名健康对照组唇腺组织中Snail、E-cad的表达情况.2组间阳性率的比较采用x2检验或Fisher's 确切概率法,相关性分析采用Spearman相关分析法.结果 E-cad在正常唇腺组织中阳性表达率为100%(30/30),而在pSS患者唇腺组织中阳性率为62%(31/50),2组间差异具有统计学意义(x2=14.651,P<0.01);Snail在正常唇腺组织阳性表达率为0,而50例pSS患者唇腺组织中20例呈阳性表达(阳性表达率为40%),2

  13. 'Special K' and a Loss of Cell-To-Cell Adhesion in Proximal Tubule-Derived Epithelial Cells: Modulation of the Adherens Junction Complex by Ketamine

    Science.gov (United States)

    Hills, Claire E.; Jin, Tianrong; Siamantouras, Eleftherios; Liu, Issac K-K; Jefferson, Kieran P.; Squires, Paul E.

    2013-01-01

    Ketamine, a mild hallucinogenic class C drug, is the fastest growing ‘party drug’ used by 16–24 year olds in the UK. As the recreational use of Ketamine increases we are beginning to see the signs of major renal and bladder complications. To date however, we know nothing of a role for Ketamine in modulating both structure and function of the human renal proximal tubule. In the current study we have used an established model cell line for human epithelial cells of the proximal tubule (HK2) to demonstrate that Ketamine evokes early changes in expression of proteins central to the adherens junction complex. Furthermore we use AFM single-cell force spectroscopy to assess if these changes functionally uncouple cells of the proximal tubule ahead of any overt loss in epithelial cell function. Our data suggests that Ketamine (24–48 hrs) produces gross changes in cell morphology and cytoskeletal architecture towards a fibrotic phenotype. These physical changes matched the concentration-dependent (0.1–1 mg/mL) cytotoxic effect of Ketamine and reflect a loss in expression of the key adherens junction proteins epithelial (E)- and neural (N)-cadherin and β-catenin. Down-regulation of protein expression does not involve the pro-fibrotic cytokine TGFβ, nor is it regulated by the usual increase in expression of Slug or Snail, the transcriptional regulators for E-cadherin. However, the loss in E-cadherin can be partially rescued pharmacologically by blocking p38 MAPK using SB203580. These data provide compelling evidence that Ketamine alters epithelial cell-to-cell adhesion and cell-coupling in the proximal kidney via a non-classical pro-fibrotic mechanism and the data provides the first indication that this illicit substance can have major implications on renal function. Understanding Ketamine-induced renal pathology may identify targets for future therapeutic intervention. PMID:24009666

  14. Expression of gap junction protein connexin 43 in bovine urinary bladder tumours.

    Science.gov (United States)

    Corteggio, A; Florio, J; Roperto, F; Borzacchiello, G

    2011-01-01

    The aetiopathogenesis of urinary bladder tumours in cattle involves prolonged ingestion of bracken fern and infection by bovine papillomavirus types 1 or 2 (BPV-1/2). The oncogenic activity of BPV is largely associated with the major oncoprotein E5. Gap junctions are the only communicating junctions found in animal tissues and are composed of proteins known as connexins. Alterations in connexin expression have been associated with oncogenesis. The present study investigated biochemically and immunohistochemically the expression of connexin 43 in samples of normal (n=2), dysplastic (n=3) and neoplastic (n=23) bovine urothelium. The tumours included 10 carcinomas in situ, five papillary urothelial carcinomas and eight invasive urothelial carcinomas. Normal and dysplastic urothelium had membrane expression of connexin 43, but this was reduced in samples of carcinoma in situ. Papillary urothelial carcinomas showed moderate cytoplasmic and membrane labelling, while invasive carcinoma showed loss of connexin 43 expression. Copyright © 2010 Elsevier Ltd. All rights reserved.

  15. Expression of Snail and E-cadherin in Epithelial Ovarian Cancer and Their Relationship with Epithelial-Mesenchymal Transition%Snail和E-cadherin在上皮性卵巢癌组织中的表达及其与上皮-间叶转化的关系

    Institute of Scientific and Technical Information of China (English)

    郑艳萍; 姚爱香; 鄢学菊

    2011-01-01

    Objective: To investigate the expression of epithelial-mesenchymal transition (EMT) related markers Snail and E-cadherin proteins in epithelial ovarian carcinoma and their relationship with the malignant features.Methods: The expression of Snail and E-cadherin proteins was detected in 45 cases of epithelial ovarian cancer by immunohistochemistry method and its relationship with clinic pathological data was also analyzed.Results: Snail positive expression rate was 40 % (18/45) in 45 cases of ovarian cancer, while the decreased expression of E-cadherin was found in 23 cases.The expression of Snail was significantly related to lymph node metastasis (P<0.05), distant metastasis (P< 0.01 ), and the lower expression of E-cadherin (P< 0.05).There was a clear correlation of Snail increased expression and E-cadherin decreased expression with the metastasis of ovarian cancer.Conclusion: There exists the re-expression of Snail in ovarian cancer,accompanied by decreased E-cadherin expression.Controlling epithelial-mesenchymal transition might play an important role in the invasion process of ovarian cancer.%目的:探讨上皮-间叶细胞转变(EMT)的标记分子Snail和E-cadherin在上皮性卵巢癌组织中的表达及其与卵巢癌恶性生物学行为的相关性.方法:采用免疫组化方法分别检测45例卵巢上皮性癌组织中Snail和Ecadherin的表达状况,并分析其与卵巢癌主要临床病理参数之间的关系.结果:45例卵巢癌组织中Snail阳性表达率为40%(18/45),23例中观察到E-cadherin表达的降低.Snail的表达和淋巴结转移(P<0.05)、远处转移(P<0.01),E-cadherin表达降低(P<0.05)都存在着相关性.Snail的阳性表达和E-cadherin的表达降低与卵巢癌的转移存在着明显的相关性.结论:Snail在卵巢癌组织中存在着重新表达的现象,同时伴随着E-cadherin的表达降低,调控上皮-间叶转化从而在卵巢癌的侵袭过程中发挥重要作用.

  16. The tight junction protein ZO-2 blocks cell cycle progression and inhibits cyclin D1 expression.

    Science.gov (United States)

    Gonzalez-Mariscal, Lorenza; Tapia, Rocio; Huerta, Miriam; Lopez-Bayghen, Esther

    2009-05-01

    ZO-2 is an adaptor protein of the tight junction that belongs to the MAGUK protein family. ZO-2 is a dual localization protein that in sparse cultures is present at the cell borders and the nuclei, whereas in confluent cultures it is concentrated at the cell boundaries. Here we have studied whether ZO-2 is able to regulate the expression of cyclin D1 (CD1) and cell proliferation. We have demonstrated that ZO-2 negatively regulates CD1 transcription by interacting with c-Myc at an E box present in CD1 promoter. We have further found that ZO-2 transfection into epithelial MDCK cells triggers a diminished expression of CD1 protein and decreases the rate of cell proliferation in a wound-healing assay.

  17. Tight junction protein expression of gastric mucosa and its significance in children with Helicobacter pylori infection%幽门螺杆菌感染患儿胃黏膜紧密连接蛋白表达的变化及其意义

    Institute of Scientific and Technical Information of China (English)

    李炜; 舒小莉; 顾伟忠; 彭克荣; 蔡海芳; 江丽琴; 江米足

    2015-01-01

    .75、1.15,F=5.445,P<0.05).结论 Hp感染患儿胃黏膜紧密连接蛋白E-cadherin、β-catenin、ZO-1表达降低,Hp阳性消化性溃疡患儿claudin-4表达增加,提示儿童Hp感染时胃上皮屏障功能受损可能是Hp相关性胃病的主要致病机制.%Objective To understand the junction protein expression of gastric mucosa including occlusal proteins (occludin),closed protein-4 (claudin-4),zonula occluden-1 (ZO-1),epithelial cadherin (E-cadherin),and β ring protein (β-catenin) and the clinical significance in children with Helicobacter pylori (Hp) infection.Method Seventy patients in whom gastric endoscopy was performed because of nausea,vomiting,abdominal pain,bloating,acid reflux,melena,and other gastrointestinal symptoms were enrolled in this study from Dec.2010 to Apr.2013 in our hospital.Informed consent was signed by their parents,and the study was in accordance with the principles of medical ethics.Hp positivity was confirmed if both respiratory urea test (RUT) and Hp were positive by gastric mucosal pathology.Gastric mucosal samples from 70 patients were enrolled in this study,23 of them were Hp negative,47 of them were Hp positive (24 cases without peptic ulcer,23 cases with peptic ulcer).The mRNA levels and protein expression of tight junction protein of gastric mucosa were measured by RT-PCR and Western blot respectively.The location and semi quantitative content of E-cadherin and β-catenin in gastric mucosa were detected by immunohistochemical staining method.Result The mRNA level of E-cadherin,β-catenin,ZO-1 in the Hp positive group regardless of peptic ulcer was significantly lower than that in the Hp negative group.Hp positive without peptic ulcer group were 0.000 8,0.004 0,0.001 4,respectively;Hp positive with peptic ulcer group were 0.001 0,0.009 0,0.001 3,respectively;Hp negative group were 0.013 7,0.042 3,0.019 8,respectively (F values were 36.956,39.893,38.962,respectively,all P < 0.05).The expression of claudin-4 mRNA in Hp

  18. Pancreatic Cancer Cell Glycosylation Regulates Cell Adhesion and Invasion through the Modulation of α2β1 Integrin and E-Cadherin Function

    Science.gov (United States)

    Bassagañas, Sònia; Carvalho, Sandra; Dias, Ana M.; Pérez-Garay, Marta; Ortiz, M. Rosa; Figueras, Joan; Reis, Celso A.; Pinho, Salomé S.; Peracaula, Rosa

    2014-01-01

    In our previous studies we have described that ST3Gal III transfected pancreatic adenocarcinoma Capan-1 and MDAPanc-28 cells show increased membrane expression levels of sialyl-Lewis x (SLex) along with a concomitant decrease in α2,6-sialic acid compared to control cells. Here we have addressed the role of this glycosylation pattern in the functional properties of two glycoproteins involved in the processes of cancer cell invasion and migration, α2β1 integrin, the main receptor for type 1 collagen, and E-cadherin, responsible for cell-cell contacts and whose deregulation determines cell invasive capabilities. Our results demonstrate that ST3Gal III transfectants showed reduced cell-cell aggregation and increased invasive capacities. ST3Gal III transfected Capan-1 cells exhibited higher SLex and lower α2,6-sialic acid content on the glycans of their α2β1 integrin molecules. As a consequence, higher phosphorylation of focal adhesion kinase tyrosine 397, which is recognized as one of the first steps of integrin-derived signaling pathways, was observed in these cells upon adhesion to type 1 collagen. This molecular mechanism underlies the increased migration through collagen of these cells. In addition, the pancreatic adenocarcinoma cell lines as well as human pancreatic tumor tissues showed colocalization of SLex and E-cadherin, which was higher in the ST3Gal III transfectants. In conclusion, changes in the sialylation pattern of α2β1 integrin and E-cadherin appear to influence the functional role of these two glycoproteins supporting the role of these glycans as an underlying mechanism regulating pancreatic cancer cell adhesion and invasion. PMID:24878505

  19. Pancreatic cancer cell glycosylation regulates cell adhesion and invasion through the modulation of α2β1 integrin and E-cadherin function.

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    Sònia Bassagañas

    Full Text Available In our previous studies we have described that ST3Gal III transfected pancreatic adenocarcinoma Capan-1 and MDAPanc-28 cells show increased membrane expression levels of sialyl-Lewis x (SLe(x along with a concomitant decrease in α2,6-sialic acid compared to control cells. Here we have addressed the role of this glycosylation pattern in the functional properties of two glycoproteins involved in the processes of cancer cell invasion and migration, α2β1 integrin, the main receptor for type 1 collagen, and E-cadherin, responsible for cell-cell contacts and whose deregulation determines cell invasive capabilities. Our results demonstrate that ST3Gal III transfectants showed reduced cell-cell aggregation and increased invasive capacities. ST3Gal III transfected Capan-1 cells exhibited higher SLe(x and lower α2,6-sialic acid content on the glycans of their α2β1 integrin molecules. As a consequence, higher phosphorylation of focal adhesion kinase tyrosine 397, which is recognized as one of the first steps of integrin-derived signaling pathways, was observed in these cells upon adhesion to type 1 collagen. This molecular mechanism underlies the increased migration through collagen of these cells. In addition, the pancreatic adenocarcinoma cell lines as well as human pancreatic tumor tissues showed colocalization of SLe(x and E-cadherin, which was higher in the ST3Gal III transfectants. In conclusion, changes in the sialylation pattern of α2β1 integrin and E-cadherin appear to influence the functional role of these two glycoproteins supporting the role of these glycans as an underlying mechanism regulating pancreatic cancer cell adhesion and invasion.

  20. Melanocyte migration is influenced by E-cadherin-dependent adhesion of keratinocytes in both two- and three-dimensional in vitro wound models.

    Science.gov (United States)

    Keswell, Dheshnie; Kidson, Susan H; Davids, Lester M

    2015-02-01

    During wound healing, melanocytes are required to migrate into the wounded area that is still in the process of re-construction. The role and behaviour of melanocytes during this process is poorly understood, that is, whether melanocyte migration into the wound is keratinocyte-dependent or not. This paper attempts, through the use of both two- and three-dimensional in vitro models, to understand the role and behaviour of melanocytes during the process of wound healing. In addition, it sheds light on whether keratinocytes influence/contribute toward melanocyte migration and ultimately wound healing. Scratch assays were performed to analyse migration and Western blot analyses measured cellular E-cadherin expression. Immunohistochemistry was used to analyse the in vivo 3D wound healing effect. Scratch assays performed on co-cultures of melanocytes and keratinocytes demonstrated that melanocytes actively migrated, with the use of their dendrites, into the scratch ahead of the proliferating keratinocyte sheet. Migration of the melanocyte into the wound bed was accompanied by loss of attachment to keratinocytes at the wound front with concomitant downregulation of E-cadherin expression as observed through immunocytochemistry. This result suggests that, in vitro, melanocyte migration occurs independently of keratinocytes but that the migration is influenced by keratinocyte E-cadherin expression. We now demonstrate that melanocyte migration during re-pigmentation is an active process, and suggest that targeting of mechanisms involved in active melanocyte migration (e.g. the melanocyte dendrite) may enhance the re-pigmentation process. © 2014 International Federation for Cell Biology.

  1. SPARCL1, Shp2, MSH2, E-cadherin, p53, ADCY-2 and MAPK are prognosis-related in colorectal cancer

    Institute of Scientific and Technical Information of China (English)

    Shu-Jing Yu; Jie-Kai Yu; Wei-Ting Ge; Han-Guang Hu; Ying Yuan; Shu Zheng

    2011-01-01

    AIM: To investigate the expression of markers that are correlated with the prognosis of colorectal cancer (CRC) patients.METHODS: One hundred and fifty-six CRC patients were followed up for more than 3 years after radical surgery. Immunohistochemical (IHC) analysis was per-formed to detect the expression of 14 pathway-related markers (p53, APC, p21ras, E-cadherin, endothelin-B receptor, Shp2, ADCY-2, SPARCL1, neuroligin1, hsp27, mmp-9, MAPK, MSH2 and rho) in specimens from these patients. Bioinformatics analysis involving a Support Vector Machine (SVM) was used to determine the best prognostic model from combinations of these markers.RESULTS: Seven markers (SPARCL1, Shp2, MSH2, E-cadherin, p53, ADCY-2 and MAPK) were significantly related to the prognosis and clinical pathological features of the CRC patients (P < 0.05). Prognostic models were established through SVM from combinations of these 7 markers and proved able to differentiate patients with dissimilar survival, especially in stage Ⅱ/Ⅲ patients. Ac-cording to the best prognostic model, the p53/SPARCL1 model, patients having high p53 and low SPARCL1 ex-pression had about 50% lower 3-year survival than others (P < 0.001). CONCLUSION: SPARCL1, Shp2, MSH2, E-cadherin, p53, ADCY-2 and MAPK are potential prognostic markers in CRC. A p53/SPARCL1 bioinformatics model may be used as a supplement to tumor-nodes-metastasis staging.

  2. The expression of syndecan-1 and -2 is associated with Gleason score and epithelial-mesenchymal transition markers, E-cadherin and beta-catenin, in prostate cancer.

    Science.gov (United States)

    Contreras, Hector R; Ledezma, Rodrigo A; Vergara, Jorge; Cifuentes, Federico; Barra, Cristina; Cabello, Pablo; Gallegos, Ivan; Morales, Bernardo; Huidobro, Christian; Castellón, Enrique A

    2010-01-01

    The epithelial-mesenchymal transition (EMT) is considered a key step in tumor progression, where the invasive cancer cells change from epithelial to mesenchymal phenotype. During this process, a decrease or loss in adhesion molecules expression and an increase in migration molecules expression are observed. The aim of this work was to determine the expression and cellular distribution of syndecan-1 and -2 (migration molecules) and E-cadherin and beta-catenin (adhesion molecules) in different stages of prostate cancer progression. A quantitative immunohistochemical study of these molecules was carried out in tissue samples from benign prostatic hyperplasia and prostate carcinoma, with low and high Gleason score, obtained from biopsies archives of the Clinic Hospital of the University of Chile and Dipreca Hospital. Polyclonal specific antibodies and amplification system of estreptavidin-biotin peroxidase and diaminobenzidine were used. Syndecan-1 was uniformly expressed in basolateral membranes of normal epithelium, changing to a granular cytoplasmatic expression pattern in carcinomas. Syndecan-2 was observed mainly in a cytoplasmatic granular pattern, with high immunostaining intensity in areas of low Gleason score. E-cadherin was detected in basolateral membrane of normal epithelia showing decreased expression in high Gleason score samples. beta-Catenin was found in cell membranes of normal epithelia changing its distribution toward the nucleus and cytoplasm in carcinoma samples. We concluded that changes in expression and cell distribution of E-cadherin and beta-catenin correlated with the progression degree of prostate adenocarcinoma, suggesting a role of these molecules as markers of progression and prognosis. Furthermore, changes in the pattern expression of syndecan-1 and -2 indicate that both molecules may be involved in the EMT and tumor progression of prostate cancer.

  3. LincRNA-p21 inhibits invasion and metastasis of hepatocellular carcinoma through miR-9/E-cadherin cascade signaling pathway molecular mechanism

    Directory of Open Access Journals (Sweden)

    Ding G

    2017-06-01

    Full Text Available Gangqiang Ding, Zhen Peng, Jia Shang, Yi Kang, Huibin Ning, Chongshan Mao Department of Infectious Diseases, People’s Hospital of Zhengzhou University, Henan Provincial People’s Hospital, Zhengzhou, China Abstract: In the previous study, it was found that long intergenic noncoding RNA-p21 (lincRNA-p21 was downregulated in hepatocellular carcinoma (HCC and lincRNA-p21 overexpression inhibited tumor invasion through inducing epithelial–mesenchymal transition. However, the underlying mechanism was not fully elaborated. In this study, lincRNA-p21 expression was measured in 12 paired HCC and nontumor adjacent normal tissues by ­quantitative real-time polymerase chain reaction. The effects of lincRNA-p21 on HCC cells were studied using lentivirus expressing lincRNA-p21 vector in vitro. The association between lincRNA-p21 level and miR-9 level was tested with the Spearman rank correlation. The effects of miR-9 on HCC cells were studied by using miR-9 inhibitor in vitro. Luciferase assay was used to validate the target of miR-9. The results showed that lincRNA-p21 was downregulated in human HCC tissues and cell lines. LincRNA-p21 overexpression significantly inhibited HCC cell migration and invasion in vitro. Besides, lincRNA-p21 negatively regulated miR-9 expression level, and miR-9 was upregulated in human HCC tissues and cells. MiR-9 knockdown inhibited HCC cell migration and invasion in vitro. Finally, the luciferase assay results showed that E-cadherin was a direct target of miR-9. The expression level of E-cadherin was found to be regulated by lincRNA-p21 and miR-9. Altogether, the results suggested that lincRNA-p21 inhibits migration and invasion of HCC cells through regulating miR-9-mediated E-cadherin cascade signaling pathway. Keywords: hepatocellular carcinoma, lincRNA-p21, miR-9, E-cadherin, epithelial–mesenchymal transition

  4. Dendrobium chrysotoxum Lindl. Alleviates Diabetic Retinopathy by Preventing Retinal Inflammation and Tight Junction Protein Decrease

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    Zengyang Yu

    2015-01-01

    Full Text Available Diabetic retinopathy (DR is a serious complication of diabetes mellitus. This study aimed to observe the alleviation of the ethanol extract of Dendrobium chrysotoxum Lindl. (DC, a traditional Chinese herbal medicine, on DR and its engaged mechanism. After DC (30 or 300 mg/kg was orally administrated, the breakdown of blood retinal barrier (BRB in streptozotocin- (STZ- induced diabetic rats was attenuated by DC. Decreased retinal mRNA expression of tight junction proteins (including occludin and claudin-1 in diabetic rats was also reversed by DC. Western blot analysis and retinal immunofluorescence staining results further confirmed that DC reversed the decreased expression of occludin and claudin-1 proteins in diabetic rats. DC reduced the increased retinal mRNA expressions of intercellular adhesion molecule-1 (ICAM-1, tumor necrosis factor α (TNFα, interleukin- (IL- 6, and IL-1β in diabetic rats. In addition, DC alleviated the increased 1 and phosphorylated p65, IκB, and IκB kinase (IKK in diabetic rats. DC also reduced the increased serum levels of TNFα, interferon-γ (IFN-γ, IL-6, IL-1β, IL-8, IL-12, IL-2, IL-3, and IL-10 in diabetic rats. Therefore, DC can alleviate DR by inhibiting retinal inflammation and preventing the decrease of tight junction proteins, such as occludin and claudin-1.

  5. Activation of EGFR promotes squamous carcinoma SCC10A cell migration and invasion via inducing EMT-like phenotype change and MMP-9-mediated degradation of E-cadherin.

    Science.gov (United States)

    Zuo, Jian-Hong; Zhu, Wei; Li, Mao-Yu; Li, Xin-Hui; Yi, Hong; Zeng, Gu-Qing; Wan, Xun-Xun; He, Qiu-Yan; Li, Jian-Huang; Qu, Jia-Quan; Chen, Yu; Xiao, Zhi-Qiang

    2011-09-01

    EGFR is a potent stimulator of invasion and metastasis in head and neck squamous cell carcinomas (HNSCC). However, the mechanism by which EGFR may stimulate tumor cell invasion and metastasis still need to be elucidated. In this study, we showed that activation of EGFR by EGF in HNSCC cell line SCC10A enhanced cell migration and invasion, and induced loss of epitheloid phenotype in parallel with downregulation of E-cadherin and upregulation of N-cadherin and vimentin, indicating that EGFR promoted SCC10A cell migration and invasion possibly by an epithelial to mesenchymal transition (EMT)-like phenotype change. Interestingly, activation of EGFR by EGF induced production of matrix metalloproteinase-9 (MMP-9) and soluble E-cadherin (sE-cad), and knockdown of MMP-9 by siRNA inhibited sE-cad production induced by EGF in SCC10A. Moreover, both MMP-9 knockdown and E-cadherin overexpression inhibited cell migration and invasion induced by EGF in SCC10A. The results indicate that EGFR activation promoted cell migration and invasion through inducing MMP-9-mediated degradation of E-cadherin into sE-cad. Pharmacologic inhibition of EGFR, MEK, and PI3K kinase activity in SCC10A reduced phosphorylated levels of ERK-1/2 and AKT, production of MMP-9 and sE-cad, cell migration and invasion, and expressional changes of EMT markers (E-cadherin and N-cadherin) induced by EGF, indicating that EGFR activation promotes cell migration and invasion via ERK-1/2 and PI3K-regulated MMP-9/E-cadherin signaling pathways. Taken together, the data suggest that EGFR activation promotes HNSCC SCC10A cell migration and invasion by inducing EMT-like phenotype change and MMP-9-mediated degradation of E-cadherin into sE-cad related to activation of ERK-1/2 and PI3K signaling pathways.

  6. Petri Net-Based Model of Helicobacter pylori Mediated Disruption of Tight Junction Proteins in Stomach Lining during Gastric Carcinoma

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    Anam Naz

    2017-09-01

    Full Text Available Tight junctions help prevent the passage of digestive enzymes and microorganisms through the space between adjacent epithelial cells lining. However, Helicobacter pylori encoded virulence factors negatively regulate these tight junctions and contribute to dysfunction of gastric mucosa. Here, we have predicted the regulation of important tight junction proteins, such as Zonula occludens-1, Claudin-2 and Connexin32 in the presence of pathogenic proteins. Molecular events such as post translational modifications and crosstalk between phosphorylation, O-glycosylation, palmitoylation and methylation are explored which may compromise the integrity of these tight junction proteins. Furthermore, the signaling pathways disrupted by dysregulated kinases, proteins and post-translational modifications are reviewed to design an abstracted computational model showing the situation-dependent dynamic behaviors of these biological processes and entities. A qualitative hybrid Petri Net model is therefore constructed showing the altered host pathways in the presence of virulence factor cytotoxin-associated gene A, leading to the disruption of tight junction proteins. The model is qualitative logic-based, which does not depend on any kinetic parameter and quantitative data and depends on knowledge derived from experiments. The designed model provides insights into the tight junction disruption and disease progression. Model is then verified by the available experimental data, nevertheless formal in vitro experimentation is a promising way to ensure its validation. The major findings propose that H. pylori activated kinases are responsible to trigger specific post translational modifications within tight junction proteins, at specific sites. These modifications may favor alterations in gastric barrier and provide a route to bacterial invasion into host cells.

  7. Simvastatin Sodium Salt and Fluvastatin Interact with Human Gap Junction Gamma-3 Protein.

    Science.gov (United States)

    Marsh, Andrew; Casey-Green, Katherine; Probert, Fay; Withall, David; Mitchell, Daniel A; Dilly, Suzanne J; James, Sean; Dimitri, Wade; Ladwa, Sweta R; Taylor, Paul C; Singer, Donald R J

    2016-01-01

    Finding pleiomorphic targets for drugs allows new indications or warnings for treatment to be identified. As test of concept, we applied a new chemical genomics approach to uncover additional targets for the widely prescribed lipid-lowering pro-drug simvastatin. We used mRNA extracted from internal mammary artery from patients undergoing coronary artery surgery to prepare a viral cardiovascular protein library, using T7 bacteriophage. We then studied interactions of clones of the bacteriophage, each expressing a different cardiovascular polypeptide, with surface-bound simvastatin in 96-well plates. To maximise likelihood of identifying meaningful interactions between simvastatin and vascular peptides, we used a validated photo-immobilisation method to apply a series of different chemical linkers to bind simvastatin so as to present multiple orientations of its constituent components to potential targets. Three rounds of biopanning identified consistent interaction with the clone expressing part of the gene GJC3, which maps to Homo sapiens chromosome 7, and codes for gap junction gamma-3 protein, also known as connexin 30.2/31.3 (mouse connexin Cx29). Further analysis indicated the binding site to be for the N-terminal domain putatively 'regulating' connexin hemichannel and gap junction pores. Using immunohistochemistry we found connexin 30.2/31.3 to be present in samples of artery similar to those used to prepare the bacteriophage library. Surface plasmon resonance revealed that a 25 amino acid synthetic peptide representing the discovered N-terminus did not interact with simvastatin lactone, but did bind to the hydrolysed HMG CoA inhibitor, simvastatin acid. This interaction was also seen for fluvastatin. The gap junction blockers carbenoxolone and flufenamic acid also interacted with the same peptide providing insight into potential site of binding. These findings raise key questions about the functional significance of GJC3 transcripts in the vasculature and

  8. Simvastatin Sodium Salt and Fluvastatin Interact with Human Gap Junction Gamma-3 Protein.

    Directory of Open Access Journals (Sweden)

    Andrew Marsh

    Full Text Available Finding pleiomorphic targets for drugs allows new indications or warnings for treatment to be identified. As test of concept, we applied a new chemical genomics approach to uncover additional targets for the widely prescribed lipid-lowering pro-drug simvastatin. We used mRNA extracted from internal mammary artery from patients undergoing coronary artery surgery to prepare a viral cardiovascular protein library, using T7 bacteriophage. We then studied interactions of clones of the bacteriophage, each expressing a different cardiovascular polypeptide, with surface-bound simvastatin in 96-well plates. To maximise likelihood of identifying meaningful interactions between simvastatin and vascular peptides, we used a validated photo-immobilisation method to apply a series of different chemical linkers to bind simvastatin so as to present multiple orientations of its constituent components to potential targets. Three rounds of biopanning identified consistent interaction with the clone expressing part of the gene GJC3, which maps to Homo sapiens chromosome 7, and codes for gap junction gamma-3 protein, also known as connexin 30.2/31.3 (mouse connexin Cx29. Further analysis indicated the binding site to be for the N-terminal domain putatively 'regulating' connexin hemichannel and gap junction pores. Using immunohistochemistry we found connexin 30.2/31.3 to be present in samples of artery similar to those used to prepare the bacteriophage library. Surface plasmon resonance revealed that a 25 amino acid synthetic peptide representing the discovered N-terminus did not interact with simvastatin lactone, but did bind to the hydrolysed HMG CoA inhibitor, simvastatin acid. This interaction was also seen for fluvastatin. The gap junction blockers carbenoxolone and flufenamic acid also interacted with the same peptide providing insight into potential site of binding. These findings raise key questions about the functional significance of GJC3 transcripts in the

  9. The re-expression of the epigenetically silenced e-cadherin gene by a polyamine analogue lysine-specific demethylase-1 (LSD1) inhibitor in human acute myeloid leukemia cell lines.

    Science.gov (United States)

    Murray-Stewart, Tracy; Woster, Patrick M; Casero, Robert A

    2014-03-01

    Aberrant epigenetic silencing of tumor suppressor genes is a common feature observed during the transformation process of many cancers, including those of hematologic origin. Histone modifications, including acetylation, phosphorylation, and methylation, collaborate with DNA CpG island methylation to regulate gene expression. The dynamic process of histone methylation is the latest of these epigenetic modifications to be described, and the identification and characterization of LSD1 as a demethylase of lysine 4 of histone H3 (H3K4) has confirmed that both the enzyme and the modified histone play important roles as regulators of gene expression. LSD1 activity contributes to the suppression of gene expression by demethylating promoter-region mono- and dimethyl-H3K4 histone marks that are associated with active gene expression. As most post-translational modifications are reversible, the enzymes involved in the modification of histones have become targets for chemotherapeutic intervention. In this study, we examined the effects of the polyamine analogue LSD1 inhibitor 2d (1,15-bis{N (5)-[3,3-(diphenyl)propyl]-N(1)-biguanido}-4,12-diazapentadecane) in human acute myeloid leukemia (AML) cell lines. In each line studied, 2d evoked cytotoxicity and inhibited LSD1 activity, as evidenced by increases in the global levels of mono- and di-methylated H3K4 proteins. Global increases in other chromatin modifications were also observed following exposure to 2d, suggesting a broad response to this compound with respect to chromatin regulation. On a gene-specific level, treatment with 2d resulted in the re-expression of e-cadherin, a tumor suppressor gene frequently silenced by epigenetic modification in AML. Quantitative chromatin immunoprecipitation analysis of the e-cadherin promoter further confirmed that this re-expression was concurrent with changes in both active and repressive histone marks that were consistent with LSD1 inhibition. As hematologic malignancies have

  10. Regulation of embryonic cell adhesion by the prion protein.

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    Edward Málaga-Trillo

    2009-03-01

    Full Text Available Prion proteins (PrPs are key players in fatal neurodegenerative disorders, yet their physiological functions remain unclear, as PrP knockout mice develop rather normally. We report a strong PrP loss-of-function phenotype in zebrafish embryos, characterized by the loss of embryonic cell adhesion and arrested gastrulation. Zebrafish and mouse PrP mRNAs can partially rescue this knockdown phenotype, indicating conserved PrP functions. Using zebrafish, mouse, and Drosophila cells, we show that PrP: (1 mediates Ca(+2-independent homophilic cell adhesion and signaling; and (2 modulates Ca(+2-dependent cell adhesion by regulating the delivery of E-cadherin to the plasma membrane. In vivo time-lapse analyses reveal that the arrested gastrulation in PrP knockdown embryos is due to deficient morphogenetic cell movements, which rely on E-cadherin-based adhesion. Cell-transplantation experiments indicate that the regulation of embryonic cell adhesion by PrP is cell-autonomous. Moreover, we find that the local accumulation of PrP at cell contact sites is concomitant with the activation of Src-related kinases, the recruitment of reggie/flotillin microdomains, and the reorganization of the actin cytoskeleton, consistent with a role of PrP in the modulation of cell adhesion via signaling. Altogether, our data uncover evolutionarily conserved roles of PrP in cell communication, which ultimately impinge on the stability of adherens cell junctions during embryonic development.

  11. Tight Junction Proteins Claudin-1 and Occludin Are Important for Cutaneous Wound Healing.

    Science.gov (United States)

    Volksdorf, Thomas; Heilmann, Janina; Eming, Sabine A; Schawjinski, Kathrin; Zorn-Kruppa, Michaela; Ueck, Christopher; Vidal-Y-Sy, Sabine; Windhorst, Sabine; Jücker, Manfred; Moll, Ingrid; Brandner, Johanna M

    2017-06-01

    Tight junction (TJ) proteins are known to be involved in proliferation and differentiation. These processes are essential for normal skin wound healing. Here, we investigated the TJ proteins claudin-1 and occludin in ex vivo skin wound healing models and tissue samples of acute and chronic human wounds and observed major differences in localization/expression of these proteins, with chronic wounds often showing a loss of the proteins at the wound margins and/or in the regenerating epidermis. Knockdown experiments in primary human keratinocytes showed that decreased claudin-1 expression resulted in significantly impaired scratch wound healing, with delayed migration and reduced proliferation. Activation of AKT pathway was significantly attenuated after claudin-1 knockdown, and protein levels of extracellular signal-related kinase 1/2 were reduced. For occludin, down-regulation had no impact on wound healing in normal scratch assays, but after subjecting the cells to mechanical stress, which is normally present in wounds, wound healing was impaired. For both proteins we show that most of these actions are independent from the formation of barrier-forming TJ structures, thus demonstrating nonbarrier-related functions of TJ proteins in the skin. However, for claudin-1 effects on scratch wound healing were more pronounced when TJs could form. Together, our findings provide evidence for a role of claudin-1 and occludin in epidermal regeneration with potential clinical importance. Copyright © 2017 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  12. Activation of Holliday junction recognizing protein involved in the chromosomal stability and immortality of cancer cells.

    Science.gov (United States)

    Kato, Tatsuya; Sato, Nagato; Hayama, Satoshi; Yamabuki, Takumi; Ito, Tomoo; Miyamoto, Masaki; Kondo, Satoshi; Nakamura, Yusuke; Daigo, Yataro

    2007-09-15

    We identified a novel gene HJURP (Holliday junction-recognizing protein) whose activation seemed to play a pivotal role in the immortality of cancer cells. HJURP was considered a possible downstream target for ataxia telangiectasia mutated signaling, and its expression was increased by DNA double-strand breaks (DSB). HJURP was involved in the homologous recombination pathway in the DSB repair process through interaction with hMSH5 and NBS1, which is a part of the MRN protein complex. HJURP formed nuclear foci in cells at S phase and those subjected to DNA damage. In vitro assays implied that HJURP bound directly to the Holliday junction and rDNA arrays. Treatment of cancer cells with small interfering RNA (siRNA) against HJURP caused abnormal chromosomal fusions and led to genomic instability and senescence. In addition, HJURP overexpression was observed in a majority of lung cancers and was associated with poor prognosis as well. We suggest that HJURP is an indispensable factor for chromosomal stability in immortalized cancer cells and is a potential novel therapeutic target for the development of anticancer drugs.

  13. EMP-1 is a junctional protein in a liver stem cell line and in the liver.

    Science.gov (United States)

    Lee, Hsuan-Shu; Sherley, James L; Chen, Jeremy J W; Chiu, Chien-Chang; Chiou, Ling-Ling; Liang, Ja-Der; Yang, Pan-Chyr; Huang, Guan-Tarn; Sheu, Jin-Chuan

    2005-09-09

    In an attempt to discover cell markers for liver stem cells, a cDNA microarray analysis was carried out to compare the gene expression profiles between an adult liver stem cell line, Lig-8, and mature hepatocytes. Several genes in the categories of extracellular matrix, cell membrane, cell adhesion, transcription factor, signal molecule, transporter, and metabolic enzyme were shown to be differentially expressed in Lig-8 cells. Among them, epithelial membrane protein (EMP)-1 has been previously implicated with stem cell phenotypes. Antiserum to EMP-1 was produced to localize its expression. On monolayers of Lig-8 cells, EMP-1 was expressed along the intercellular border. In the liver harboring proliferating oval cells, the liver progenitors, EMP-1 was localized as ribbon bands, a staining pattern for epithelial junctions, all the way through bile duct epithelia, oval cell ductules, and into peri-hepatocytic regions. These peri-hepatocytic regions were proved to be bile canaliculi by co-localization of EMP-1 and dipeptidyl peptidase IV, an enzyme located on bile canaliculi. This report is the first to indicate EMP-1 to be a junctional protein in the liver.

  14. Tight junction protein claudin 4 in gastric carcinoma and its relation to lymphangiogenic activity.

    Science.gov (United States)

    Shareef, Mohamed Moustafa; Radi, Dina Mohammed Adel; Eid, Asmaa Mustafa Mohammed

    2015-01-01

    Gastric cancer is the second most common cause of cancer-related death worldwide. Claudins are a family of tight junction proteins that are biologically relevant in many cancer progression steps. This study aimed to investigate the expression of the intestinal claudin (claudin 4) in gastric carcinoma and to evaluate its relation to the different clinicopathologic prognostic parameters, especially lymphangiogenesis (production of new lymphatic vessels, measured by lymphovascular density (LVD)) and lymphovascular invasion (LVI). Fifty-five gastric carcinoma specimens were immunohistochemically stained for claudin 4 and D2-40 (for detection of lymphatic vessel endothelium). High expression of claudin 4 was detected in 26 of 55 (47.3%) cases. Low expression of claudin 4 was related to poorly differentiated type (p=0.001), non-intestinal (diffuse) type (p=0.001), deeper tumour invasion (pgastric carcinoma and lost in poorly differentiated diffuse type. So, claudin 4 may be used as one of the differentiating markers between the two major types of gastric carcinoma (intestinal vs. diffuse). LVD and LVI were related to higher incidence of lymph node metastasis and therefore could be used as predictive markers for lymph node metastasis in limited specimens during early gastric carcinoma to determine the need for more invasive surgery. Low expression of claudin 4 was related to lymphangiogenesis. This may shed light on the relation of tight junction protein expression and lymphangiogenesis. Copyright © 2015 Arab Journal of Gastroenterology. Published by Elsevier B.V. All rights reserved.

  15. Thermo-chemotherapy Induced miR-218 upregulation inhibits the invasion of gastric cancer via targeting Gli2 and E-cadherin.

    Science.gov (United States)

    Ruan, Qiang; Fang, Zhi-Yuan; Cui, Shu-Zhong; Zhang, Xiang-Liang; Wu, Yin-Bing; Tang, Hong-Sheng; Tu, Yi-Nuo; Ding, Yan

    2015-08-01

    Thermo-chemotherapy has been proven to reduce the invasion capability of cancer cells. However, the molecular mechanism underlying this anti-invasion effect is still unclear. In this study, the role of thermo-chemotherapy in the inhibition of tumor invasion was studied. The results demonstrated that expression of miR-218 was downregulated in gastric cancer tissues, which had a positive correlation with tumor invasion and metastasis. In vitro thermo-chemotherapy increased miR-218 expression in SGC7901 cells and inhibited both proliferation and invasion of cancer cells. Gli2 was identified as a downstream target of miR-218, and its expression was negatively regulated by miR-218. The thermo-chemotherapy induced miR-218 upregulation was also accompanied by increasing of E-cadherin expression. In conclusion, the present study indicates that thermo-chemotherapy can effectively decrease the invasion capability of cancer cells and increase cell-cell adhesion. miR-218 and its downstream target Gli2, as well as E-cadherin, participate in the anti-invasion process.

  16. E-cadherin gene C-160A promoter polymorphism and risk of non-cardia gastric cancer in a Chinese population

    Institute of Scientific and Technical Information of China (English)

    Yan Lu; Yao-Chu Xu; Jing Shen; Rong-Bin Yu; Ju-Yin Niu; Jian-Tao Guo; Xu Hu; Hong-Bing Shen

    2005-01-01

    AIM: To test the hypothesis that E-cadherin gene (CDH1)C-160A promoter variant genotype is associated with an increased risk for developing gastric cancer.METHODS: In this population-based case-control study of gastric cancer in Jiangsu Province, China, we performed polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) to genotype the C-160A polymorphism of CDH1 promoter in 206 non-cardia gastriccancer patients and 261 age- and sex-matched but unrelated cancer-free controls.RESULTS: The frequencies of genotypes CC, CA and AA were 57.8%, 36.4% and 5.8% in gasfric cancer cases,respectively, and 58.2%, 34.9% and 6.9% in controls respectively. The distributions of CDH1 genotypes were not significantly different between gastric cancer cases and controls (P = 0.87 for genotype frequency and P = 0.92for allele frequency). Compared with the CC genotype, the CA and AA genotypes were not associated with an increased risk for non-cardia gastric cancer (adjusted odds ratios (OR)= 1.15, and 95% confidence interval (95% CI) = 0.78-1.72for CA genotype, and OR = 0.90 and 95% CI = 0.42-2.01for AA genotype).CONCLUSION: E-cadherin gene C-160A promoter polymorphism may not play a major role in the etiology of non-cardia gastric cancer in Chinese population.

  17. Deciphering Seed Sequence Based Off-Target Effects in a Large-Scale RNAi Reporter Screen for E-Cadherin Expression.

    Directory of Open Access Journals (Sweden)

    Robert Adams

    Full Text Available Functional RNAi based screening is affected by large numbers of false positive and negative hits due to prevalent sequence based off-target effects. We performed a druggable genome targeting siRNA screen intended to identify novel regulators of E-cadherin (CDH1 expression, a known key player in epithelial mesenchymal transition (EMT. Analysis of primary screening results indicated a large number of false-positive hits. To address these crucial difficulties we developed an analysis method, SENSORS, which, similar to published methods, is a seed enrichment strategy for analyzing siRNA off-targets in RNAi screens. Using our approach, we were able to demonstrate that accounting for seed based off-target effects stratifies primary screening results and enables the discovery of additional screening hits. While traditional hit detection methods are prone to false positive results which are undetected, we were able to identify false positive hits robustly. Transcription factor MYBL1 was identified as a putative novel target required for CDH1 expression and verified experimentally. No siRNA pool targeting MYBL1 was present in the used siRNA library. Instead, MYBL1 was identified as a putative CDH1 regulating target solely based on the SENSORS off-target score, i.e. as a gene that is a cause for off-target effects down regulating E-cadherin expression.

  18. Evaluation of p53, HoxD10, and E-Cadherin Status in Breast Cancer and Correlation with Histological Grade and Other Prognostic Factors

    Directory of Open Access Journals (Sweden)

    Preethi Sekar

    2014-01-01

    Full Text Available Background. Study of tumor molecular characteristics is necessary to understand both the risk of breast cancer recurrence and the response to therapy. Aims. To evaluate p53, HoxD10, and E-cadherin status in breast cancer and to correlate with histological grade and other prognostic factors. Material and Methods. The study was conducted in 60 cases of invasive ductal carcinoma NOS with 20 cases belonging to each grade and evaluation of p53 was done by IHC and that of HoxD10 and E Cadherin status by PCR and correlation was done with histological grade and other prognostic factors. Result. p53 expression was seen in 71.67% (43/60 of the tumors. HoxD10 gene was downregulated in 46.67% (28/60 of the tumors. p53 overexpression and lower HoxD10 mRNA levels showed statistically significant association higher histological grade of the tumor (P<0.05. CDH1 gene mutation was seen in 60% (15/25 of the tumors. No significant association was found between p53 expression, HoxD10 gene, CDH1 gene mutation, and other prognostic factors. Conclusion. p53 over expression and lower HoxD10 mRNA levels were found to be significantly associated with higher grade tumours. This suggests that p53 and HoxD10 gene play an important tumor suppressor role and the loss of which results in breast cancer progression.

  19. A Gap Junction Protein, Inx2, Modulates Calcium Flux to Specify Border Cell Fate during Drosophila oogenesis

    Science.gov (United States)

    Ghosh, Ritabrata; Deshpande, Girish

    2017-01-01

    Intercellular communication mediated by gap junction (GJ) proteins is indispensable during embryogenesis, tissue regeneration and wound healing. Here we report functional analysis of a gap junction protein, Innexin 2 (Inx2), in cell type specification during Drosophila oogenesis. Our data reveal a novel involvement of Inx2 in the specification of Border Cells (BCs), a migratory cell type, whose identity is determined by the cell autonomous STAT activity. We show that Inx2 influences BC fate specification by modulating STAT activity via Domeless receptor endocytosis. Furthermore, detailed experimental analysis has uncovered that Inx2 also regulates a calcium flux that transmits across the follicle cells. We propose that Inx2 mediated calcium flux in the follicle cells stimulates endocytosis by altering Dynamin (Shibire) distribution which is in turn critical for careful calibration of STAT activation and, thus for BC specification. Together our data provide unprecedented molecular insights into how gap junction proteins can regulate cell-type specification. PMID:28114410

  20. Protein preconcentration using nanofractures generated by nanoparticle-assisted electric breakdown at junction gaps.

    Directory of Open Access Journals (Sweden)

    Chun-Ping Jen

    Full Text Available Sample preconcentration is an important step that increases the accuracy of subsequent detection, especially for samples with extremely low concentrations. Due to the overlapping of electrical double layers in the nanofluidic channel, the concentration polarization effect can be generated by applying an electric field. Therefore, a nonlinear electrokinetic flow is induced, which results in the fast accumulation of proteins in front of the induced ionic depletion zone, the so-called exclusion-enrichment effect. Nanofractures were created in this work to preconcentrate proteins via the exclusion-enrichment effect. The protein sample was driven by electroosmotic flow and accumulated at a specific location. The preconcentration chip for proteins was fabricated using simple standard soft lithography with a polydimethylsiloxane replica. Nanofractures were formed by utilizing nanoparticle-assisted electric breakdown. The proposed method for nanofracture formation that utilizes nanoparticle deposition at the junction gap between microchannels greatly decreases the required electric breakdown voltage. The experimental results indicate that a protein sample with an extremely low concentration of 1 nM was concentrated to 1.5×10(4-fold in 60 min using the proposed chip.

  1. Photoperiod-Dependent Effects of 4-tert-Octylphenol on Adherens and Gap Junction Proteins in Bank Vole Seminiferous Tubules

    Directory of Open Access Journals (Sweden)

    Anna Hejmej

    2013-01-01

    Full Text Available In the present study we evaluated in vivo and in vitro effects of 4-tert-octylphenol (OP on the expression and distribution of adherens and gap junction proteins, N-cadherin, β-catenin, and connexin 43 (Cx43, in testes of seasonally breeding rodents, bank voles. We found that in bank vole testes expression and distribution of N-cadherin, β-catenin, and Cx43 were photoperiod dependent. Long-term treatment with OP (200 mg/kg b.w. resulted in the reduction of junction proteins expressions (P<0.05, P<0.01 and their delocalization in the testes of males kept in long photoperiod, whereas in short-day animals slight increase of Cx43 (P<0.05, N-cadherin, and β-catenin (statistically nonsignificant levels was observed. Effects of OP appeared to be independent of FSH and were maintained during in vitro organ culture, indicating that OP acts directly on adherens and gap junction proteins in the testes. An experiment performed using an antiestrogen ICI 182,780 demonstrated that the biological effects of OP on β-catenin and Cx43 involve an estrogen receptor-mediated response. Taken together, in bank vole organization of adherens and gap junctions and their susceptibility to OP are related to the length of photoperiod. Alterations in cadherin/catenin and Cx43-based junction may partially result from activation of estrogen receptor α and/or β signaling pathway.

  2. Effect of FCCP on tight junction permeability and cellular distribution of ZO-1 protein in epithelial (MDCK) cells.

    Science.gov (United States)

    Li, C X; Poznansky, M J

    1990-12-14

    The effect of the uncoupler of oxidative phosphorylation, FCCP (carbonylcyanide p-trifluoromethoxyphenylhydrazone), on the tight junction of Madin-Darby canine kidney cells was examined. FCCP induced an abrupt decrease in the transepithelial electrical resistance of the confluent monolayers over a period of 20 s. When FCCP was withdrawn from the incubation medium, the monolayer resistance recovered to close to the original level in less than 2 h. Staining of the tight junction-associated protein ZO-1 showed that the changes in transepithelial electrical resistance were accompanied by a diffusing of the protein away from cell peripheries and a reconcentration to the tight junction areas following resistance recovery. Intracellular pH was decreased by FCCP on a similar time-scale with no obvious changes in ATP levels over this time-course. These data suggest that the uncoupler FCCP has a profound effect on tight junction permeability and cellular distribution of the tight junction protein ZO-1 in the epithelial cells and that it probably acts by breaking down proton gradients and altering intracellular pH.

  3. 联合检测Shh Gli1 Snail及E-cadher in在胃癌中的表达及其意义%Combined Detection of Shh, Gli1, Snail and E-cadherin Expression in Gastric Cancer and Its Significance

    Institute of Scientific and Technical Information of China (English)

    郝亚琴; 欧阳小波; 王立

    2011-01-01

    Objective: To investigate the expression of Shh, Gli1, Snail and E-cadherin in gastric cancer ( GC ) and its significance.Methods: Immunohistochemistry was used to detect the expression of Shh, Gli1, Snail and E-cadherin proteins in 54 cases of GC tissues, their adjacent tissues and 30 cases of normal human gastric mucosa tissues.The correlation of Shh, Gli1, Snail and E-cadherin expression with the clinicopathologic features of GC was analyzed.Results: The positive rate of Shh, Gli1, Snail and E -cadherin expression was 68.52%, 61.11%, 77.78% and 25.93% in GC tissues, 27.78%, 24.07%, 40.74% and 70.37% in the paraneoplastic tissues, and 36.67%, 26.67%, 30% and 96.67% in the normal human gastric mucosa, with a statistical significance between GC tissues and paraneoplastic tissues ( P < 0.05 ).There was no statistical difference in the expression of Shh, Gli1 and Snail between paraneoplastic tissues and normal gastric mucosa ( P > 0.05 ), while the difference in the E-cadherin expression was statistically significant ( P < 0.05 ).The expression of these four proteins was correlated with tumor differentiation and lymph node metastasis ( P < 0.05 ).The expression of Shh, Gli1 and Snail was related to the depth of invasion, while the E-cadherin expression was not ( P > 0.05 ).The expression of the above four proteins was not correlated with sex, age, location or distant metastasis ( P > 0.05 ).The expression of Shh, Gli1 and Snail was positively correlated with each other in GC ( P < 0.05 ), but was negatively correlated with E-cadherin ( P < 0.05 ).Conclusion: The expression of molecules involved in Hedgehog signaling pathway and Epithelial- mesenchymal transition (EMT) is abnormal in GC.The abnormally activated Hedgehog signaling pathway may lead to the abnormal expression of EMT related molecules and this mechanism may play a certain role in the oncogenesis and progression of gastric cancer.%目的:探讨Shh、Gli1、Snail及E

  4. The epithelial membrane protein 1 is a novel tight junction protein of the blood-brain barrier.

    Science.gov (United States)

    Bangsow, Thorsten; Baumann, Ewa; Bangsow, Carmen; Jaeger, Martina H; Pelzer, Bernhard; Gruhn, Petra; Wolf, Sabine; von Melchner, Harald; Stanimirovic, Danica B

    2008-06-01

    In the central nervous system, a constant microenvironment required for neuronal cell activity is maintained by the blood-brain barrier (BBB). The BBB is formed by the brain microvascular endothelial cells (BMEC), which are sealed by tight junctions (TJ). To identify genes that are differentially expressed in BMEC compared with peripheral endothelial cells, we constructed a subtractive cDNA library from porcine BMEC (pBMEC) and aortic endothelial cells (AOEC). Screening the library for differentially expressed genes yielded 26 BMEC-specific transcripts, such as solute carrier family 35 member F2 (SLC35F2), ADP-ribosylation factor-like 5B (ARL5B), TSC22 domain family member 1 (TSC22D1), integral membrane protein 2A (ITM2A), and epithelial membrane protein 1 (EMP1). In this study, we show that EMP1 transcript is enriched in pBMEC compared with brain tissue and that EMP1 protein colocalizes with the TJ protein occludin in mouse BMEC by coimmunoprecipitation and in rat brain vessels by immunohistochemistry. Epithelial membrane protein 1 expression was transiently induced in laser-capture microdissected rat brain vessels after a 20-min global cerebral ischemia, in parallel with the loss of occludin immunoreactivity. The study identifies EMP1 as a novel TJ-associated protein of the BBB and suggests its potential role in the regulation of the BBB function in cerebral ischemia.

  5. The role of epidermal growth factor receptor and E-cadherin for the outcome of reduction in the overall treatment time of radiotherapy of supraglottic larynx squamous cell carcinoma

    DEFF Research Database (Denmark)

    Eriksen, Jesper Grau; Steiniche, Torben; Overgaard, Jens

    2005-01-01

    radiotherapy. A total of 209 patients from randomized DAHANCA-trials with supraglottic larynx squamous cell carcinomas treated with primary radiotherapy with different OTT of 9(1/2), 6(1/2), and 5(1/2) weeks. Available formalin-fixed paraffin embedded tumour tissues were re-evaluated for histopathological...... determining this response. The aim of the present study was to identify the influence of the epidermal growth factor receptor (EGFr) and E-cadherin for T-site control when the OTT was reduced and whether the markers add information to the histopathological grading in selecting patients for accelerated...... characteristics and stained for EGFr and E-cadherin. Data were correlated with patient and tumour characteristics and 5-year T-site control. EGFr and E-cadherin were not associated with patient or tumour characteristics except that EGFr correlated to carcinomas with a well to moderate histopathological feature...

  6. E-Cadherin在修复性牙本质形成中的免疫组化研究%Immunohistochemistry study of E - cadherin in reparative dentinogenesis

    Institute of Scientific and Technical Information of China (English)

    陈智; 樊明文; 边专; 吕平; 张旗

    2000-01-01

    目的:观察细胞粘附分子E-cadherin在修复性牙本质形成中的免疫反应和免疫定位。方法:在大鼠上、下颌第一磨牙近中面制备单面洞,分别观察3、15和30d。标本行常规组织学处理。利用鼠抗E-cadherin和免疫组化SABC法,对标本进行标记,HE复染。结果:E-cadherin在术后3d成牙本质细胞染色较弱,牙髓细胞为阳性;15d后,成牙本质细胞样细胞和牙髓细胞染色阳性;30d后,成牙本质细胞样细胞出现极化,胞浆阳性染色明显。结论:E-cadherin可能在牙髓修复过程中参与了牙髓细胞的分化和极化过程。%AIM: To investigate the immunological reactivity of E- cadherin in the reparative dentinogenesis.METHODS: The cavity was prepared on the mesial surface of the first molar of Wistar rats. After the periods of 3, 15, 30days of post - operation, animal were sacrificed and paraffin sections were prepared through histological process. SABC method was used to detect the reactivity using rat anti - E- cadherin antibody. RESULTS: The reactivity was not evident in odontoblasts of 3 days group, but was evident in dental pulp cells; the positive staining was observed in odontoblast - like cells and pulp cells after 15 days; in 30 days, the polarized odontoblast- like cells were positively stained. CONCLUSION:E- cadherin may involve in the differentiation, and polarization of dental pulp cells.

  7. IKKε通过E-cadherin调控人脑胶质瘤迁移和侵袭能力的实验研究%Experimental research of IKKε through E-cadherin regulation of the human brain glioma migration and invasion ability

    Institute of Scientific and Technical Information of China (English)

    周西广; 杨毅; 路捷; 南阳; 甄英伟; 俞凯; 王广秀; 贾志凡; 康春生

    2016-01-01

    Objective To investigate the effect of IKKε in glioma cells on the regulation of Ecadherin expression and cell migration and invasion ability.Methods The IKKε overexpression vectors and shRNA-IKKε lentivirus were constructed.The TP483 glioma cell lines were transfected by the IKKε overexpression plasmid.The expression level of IKKε in glioma cells was upregulated.The U251 and U138 glioma cell lines were transfected by the shRNA-IKKε lentivirus,IKKε expression level in glioma cells was downregulated.The expression levels of IKKε and E-cadherin in cells were detected by RT-PCR and Western blot.The expression changes of IKKε and E-cadherin after transfecting were observed by using the immunofluorescence assay.The cell migration and invasion abilities were detected by using the scratch test and Transwell assay.Results Compared with the non-transfected group (TP483 control group),the expression level of IKKε protein increased (P =0.000),and the expression level of E-cadherin protein decreased (P =0.000) in the transfected IKKε expression plasmid group (TP483 treaed group).In the glioma cells transfected IKKε shRNA(the U251 treated group and the U138 treated group),the expression level of IKKε protein decreased significantly compared with the non-transfected group (the U251 treated group and the U138 treated group;all P < 0.05).At the same time,the expression levels of E-cadherin protein in each treated group were all increased compared with the control group (P < 0.05).The scratch repair rate of the TP483 treated group was higher than that of the control group (56.39 ± 0.93% vs.46.43 ± 1.68%;P =0.035).After transfection of overexpression plasmid for 24 h,the number of TP483 cells passing through the filter membrane increased compared with the control group (55.8 ± 6.0 vs.24.6 ± 2.3;P =0.000).The scratch repair rates of the U251 and U138 treated groups decreased compared with their respective control groups (the U251 treated group:50.40 ± 1.09

  8. Reduced expression of E-cadherin and p120-catenin and elevated expression of PLC-γ1 and PIKE are associated with aggressiveness of oral squamous cell carcinoma.

    Science.gov (United States)

    Jiang, Yi; Liao, Liyan; Shrestha, Chandrama; Ji, Shangli; Chen, Ying; Peng, Jian; Wang, Larry; Liao, Eryuan; Xie, Zhongjian

    2015-01-01

    Oral squamous cell carcinoma (OSCC) is one of the most lethal malignant tumors. The cadherin/catenin cell-cell adhesion complex plays a major role in cancer development and progression. p120-catenin (p120) is a cytoplasmic molecule closely associated with E-cadherin which activates phospholipase C-γ1 (PLC-γ1). Our previous studies indicate that activation of PLC-γ1 plays a critical role in epidermal growth factor (EGF)-induced migration and proliferation of squamous cell carcinoma (SCC) cells and phosphatidylinositol 3-kinase enhancer (PIKE) is highly expressed in SCC cells and mediates EGFR-dependent SCC cell proliferation. Our current study was to determine whether the expression of E-cadherin, p120, PLC-γ1, and PIKE, is associated with OSCC. To address this issue, we assessed levels and localization of E-cadherin, p120, PLC-γ1, and PIKE in specimen of 92 patients with OSCC by immunohistochemistry. The results showed that the expression of E-cadherin, and p120 negatively correlated with the tumor differentiation and the expression of PLC-γ1 and PIKE positively correlated with the tumor differentiation. The expression of PLC-γ1 and PIKE in OSCC stage T3 + T4 or in OSCC with lymph node metastasis was significantly higher than that in OSCC stage T1 + T2 or in OSCC without lymph node metastasis. The expression of p120 positively correlated with levels of E-cadherin but negatively correlated with levels of PLC-γ1 and PIKE in OSCC. These data indicate that increased expression of PLC-γ1 and PIKE and decreased expression of E-cadherin and p120 are associated with the aggressiveness of OSCC.

  9. Expression of gap junction proteins connexins 26, 30, and 43 in Dupuytren's disease.

    Science.gov (United States)

    Holzer, Lukas A; Cör, Andrej; Holzer, Gerold

    2014-02-01

    Dupuytren's disease (DD) is a benign fibroproliferative process of the palmar aponeurosis showing similarities to wound healing. Communication of cells involved in wound healing is mediated by the composition of gap junction (GJ) proteins. We investigated the expression of 3 GJ proteins, connexins 26, 30, and 43 (Cx26, Cx30, and Cx43) in DD. Fragments of Dupuytren's tissue from 31 patients (mean age 56 (30-76) years, 24 male) were analyzed immunohistochemically and compared to control tissue for expression of the GJ proteins Cx26, Cx30, and Cx43 and also alfa-smooth muscle actin (α-SMA). 14 of 31 samples could be attributed to the involutional phase (α-SMA positive) whereas 17 samples had to be considered cords in the residual phase (α-SMA negative). Expression of Cx26 and Cx43 was seen in 12 of the 14 samples from the involutional phase, and Cx30 was seen in 7 of these. Only 4 of the 17 samples from the residual phase showed any Cx, and there was none in the controls. The high expression of GJ proteins Cx26, Cx30, and Cx43 in α-SMA positive myofibroblast-rich nodules, which are characteristic of the active involutional phase of DD, suggests that connexins could be a novel treatment target for the treatment of DD.

  10. Regulation of gap-junction protein connexin 43 by β-adrenergic receptor stimulation in rat cardiomyocytes

    Institute of Scientific and Technical Information of China (English)

    Yi XIA; Kai-zheng GONG; Ming XU; You-yi ZHANG; Ji-hong GUO; Yao SONG; Ping ZHANG

    2009-01-01

    Aim:β-adrenergic receptor (β-AR) agonists are among the most potent factors regulating cardiac electrophysiological properties.Connexin 43 (Cx43),the predominant gap-junction protein in the heart,has an indispensable role in modulating cardiac electric activities by affecting gap-junction function.The present study investigates the effects of short-term stimulation of β-AR subtypes on Cx43 expression and gap junction intercellular communication (GJIC) function.Methods:The level of Cx43 expression in neonatal rat cardiomyocytes (NRCM) was detected by a Western blotting assay.The GJIC function was evaluated by scrape loading/dye transfer assay.Results:Stimulation of β-AR by the agonist isoproterenol for 5 min induces the up-regulation of nonphosphorylated Cx43 protein level,but not total Cx43.Selective β2-AR inhibitor ICI 118551,but not β-AR inhibitor CGP20712,could fully abolish the effect.Moreover,pretreatment with both protein kinase A inhibitor H89 and G,protein inhibitor pertussis toxin also inhibited the isoproterenol-induced increase of nonphosphorylated Cx43 expression.Isoproterenol-induced up-regulation of nonphosphorylated Cx43 is accompanied with enhanced GJIC function.Conclusion:Taken together,β2-AR stimulation increases the expression of nonphosphorylated Cx43,thereby enhancing the gating function of gap junctions in cardiac myocytes in both a protein kinase A-and G1-dependent manner.

  11. 'P-cadherin functional role is dependent on E-cadherin cellular context: a proof of concept using the breast cancer model'.

    Science.gov (United States)

    2016-05-01

    This article corrects: P-cadherin functional role is dependent on E-cadherin cellular context: a proof of concept using the breast cancer model Volume 229, Issue 5, 705–718, Article first published online: 24 January 2013. By Ana Sofia Ribeiro, Bárbara Sousa, Laura Carreto, Nuno Mendes, Ana Rita Nobre, Sara Ricardo, André Albergaria, Jorge F Cameselle-Teijeiro, Rene Gerhard, Ola Söderberg, Raquel Seruca, Manuel A Santos, Fernando Schmitt and Joana Paredes, J Pathol 2013; 229: 708–718. DOI: 10.1002/path.4143. The above article, published online on 24 January 2013 on Wiley Online Library (wileyonlinelibrary.com). The funding information, “This work was also funded by FEDER funds through the Operational Programme for Competitiveness Factors - COMPETE (FCOMP-01-0124-FEDER-021209).” was omitted from the Acknowledgements section. We apologise for any inconvenience caused.

  12. Cullin-5 and cullin-2 play a role in the development of neuromuscular junction and the female germ line of Drosophila

    Indian Academy of Sciences (India)

    Champakali Ayyub

    2011-08-01

    Cullins confer substrate specificity to E3-ligases which are multi-protein complexes involved in ubiquitin-mediated protein degradation or modification. There are six cullin genes in Drosophila melanogaster. We have raised an antibody against Cul-5 and demonstrated that it expresses in neuronal and non-neuronal cells throughout development. In the embryonic tracheal system, Cul-5 is enriched at fusion sites together with E-Cadherin and Fasciclin III. Mutations of cul-5 do not affect tracheal development but do show defects in the organization of synaptic boutons at the larval neuromuscular junction where the protein is expressed in a subset of motoneuron terminals. Loss of function of another cullin gene ‘cul-2’ results in similar defects at the larval neuromuscular junction although cul-2;cul-5 double mutants do not show an enhanced phenotype. Both cul-2 and cul-5 mutants show similar aberrations in the development of female germ line. Our results suggest that both of these cullin proteins participate in similar developmental processes.

  13. NF-kappaB represses E-cadherin expression and enhances epithelial to mesenchymal transition of mammary epithelial cells: potential involvement of ZEB-1 and ZEB-2.

    Science.gov (United States)

    Chua, H L; Bhat-Nakshatri, P; Clare, S E; Morimiya, A; Badve, S; Nakshatri, H

    2007-02-01

    The transcription factor nuclear factor kappa B (NF-kappaB) is constitutively active in both cancer cells and stromal cells of breast cancer; however, the precise role of activated NF-kappaB in cancer progression is not known. Using parental MCF10A cells and a variant that expresses the myoepithelial marker p63 stably overexpressing the constitutively active p65 subunit of NF-kappaB (MCF10A/p65), we show that NF-kappaB suppresses the expression of epithelial specific genes E-cadherin and desmoplakin and induces the expression of the mesenchymal specific gene vimentin. P65 also suppressed the expression of p63 and the putative breast epithelial progenitor marker cytokeratin 5/6. MCF10A/p65 cells were phenotypically similar to cells undergoing epithelial to mesenchymal transition (EMT). MCF10A/p65 cells failed to form characteristic acini in three-dimensional Matrigel. Analysis of parental and MCF10A/p65 cells for genes previously shown to be involved in EMT revealed elevated expression of ZEB-1 and ZEB-2 in MCF10A/p65 cells compared to parental cells. In transient transfection assays, p65 increased ZEB-1 promoter activity. Furthermore, MCF10A cells overexpressing ZEB-1 showed reduced E-cadherin and p63 expression and displayed an EMT phenotype. The siRNA against ZEB-1 or ZEB-2 reduced the number of viable MCF10A/p65 but not parental cells, suggesting the dependence of MCF10A/p65 cells to ZEB-1 and ZEB-2 for cell cycle progression or survival. MCF10A cells chronically exposed to tumor necrosis factor alpha (TNFalpha), a potent NF-kappaB inducer, also exhibited the EMT-like phenotype and ZEB-1/ZEB-2 induction, both of which were reversed following TNFalpha withdrawal.

  14. Eya1 protein phosphatase regulates tight junction formation in lung distal epithelium.

    Science.gov (United States)

    El-Hashash, Ahmed H K; Turcatel, Gianluca; Varma, Saaket; Berika, Mohamed; Al Alam, Denise; Warburton, David

    2012-09-01

    Little is known about the regulatory mechanisms underlying lung epithelial tight junction (TJ) assembly, which is inextricably linked to the preservation of epithelial polarity, and is highly coordinated by proteins that regulate epithelial cell polarity, such as aPKCζ. We recently reported that Eya1 phosphatase functions through aPKCζ-Notch1 signaling to control cell polarity in the lung epithelium. Here, we have extended these observations to TJ formation to demonstrate that Eya1 is crucial for the maintenance of TJ protein assembly in the lung epithelium, probably by controlling aPKCζ phosphorylation levels, aPKCζ-mediated TJ protein phosphorylation and Notch1-Cdc42 activity. Thus, TJs are disassembled after interfering with Eya1 function in vivo or during calcium-induced TJ assembly in vitro. These effects are reversed by reintroduction of wild-type Eya1 or partially inhibiting aPKCζ in Eya1siRNA cells. Moreover, genetic activation of Notch1 rescues Eya1(-/-) lung epithelial TJ defects. These findings uncover novel functions for the Eya1-aPKCζ-Notch1-Cdc42 pathway as a crucial regulatory mechanism of TJ assembly and polarity of the lung epithelium, providing a conceptual framework for future mechanistic and translational studies in this area.

  15. Size-dependent protein segregation at membrane interfaces

    Science.gov (United States)

    Schmid, Eva M.; Bakalar, Matthew H.; Choudhuri, Kaushik; Weichsel, Julian; Ann, Hyoung Sook; Geissler, Phillip L.; Dustin, Michael L.; Fletcher, Daniel A.

    2016-07-01

    Membrane interfaces formed at cell-cell junctions are associated with characteristic patterns of membrane proteins whose organization is critical for intracellular signalling. To isolate the role of membrane protein size in pattern formation, we reconstituted model membrane interfaces in vitro using giant unilamellar vesicles decorated with synthetic binding and non-binding proteins. We show that size differences between membrane proteins can drastically alter their organization at membrane interfaces, with as little as a ~5 nm increase in non-binding protein size driving its exclusion from the interface. Combining in vitro measurements with Monte Carlo simulations, we find that non-binding protein exclusion is also influenced by lateral crowding, binding protein affinity, and thermally driven membrane height fluctuations that transiently limit access to the interface. This sensitive and highly effective means of physically segregating proteins has implications for cell-cell contacts such as T-cell immunological synapses (for example, CD45 exclusion) and epithelial cell junctions (for example, E-cadherin enrichment), as well as for protein sorting at intracellular contact points between membrane-bound organelles.

  16. Eps homology domain endosomal transport proteins differentially localize to the neuromuscular junction

    Directory of Open Access Journals (Sweden)

    Mate Suzanne E

    2012-09-01

    Full Text Available Abstract Background Recycling of endosomes is important for trafficking and maintenance of proteins at the neuromuscular junction (NMJ. We have previously shown high expression of the endocytic recycling regulator Eps15 homology domain-containing (EHD1 proteinin the Torpedo californica electric organ, a model tissue for investigating a cholinergic synapse. In this study, we investigated the localization of EHD1 and its paralogs EHD2, EHD3, and EHD4 in mouse skeletal muscle, and assessed the morphological changes in EHD1−/− NMJs. Methods Localization of the candidate NMJ protein EHD1 was assessed by confocal microscopy analysis of whole-mount mouse skeletal muscle fibers after direct gene transfer and immunolabeling. The potential function of EHD1 was assessed by specific force measurement and α-bungarotoxin-based endplate morphology mapping in EHD1−/− mouse skeletal muscle. Results Endogenous EHD1 localized to primary synaptic clefts of murine NMJ, and this localization was confirmed by expression of recombinant green fluorescent protein labeled-EHD1 in murine skeletal muscle in vivo. EHD1−/− mouse skeletal muscle had normal histology and NMJ morphology, and normal specific force generation during muscle contraction. The EHD 1–4 proteins showed differential localization in skeletal muscle: EHD2 to muscle vasculature, EHD3 to perisynaptic regions, and EHD4 to perinuclear regions and to primary synaptic clefts, but at lower levels than EHD1. Additionally, specific antibodies raised against mammalian EHD1-4 recognized proteins of the expected mass in the T. californica electric organ. Finally, we found that EHD4 expression was more abundant in EHD1−/− mouse skeletal muscle than in wild-type skeletal muscle. Conclusion EHD1 and EHD4 localize to the primary synaptic clefts of the NMJ. Lack of obvious defects in NMJ structure and muscle function in EHD1−/− muscle may be due to functional compensation by other EHD paralogs.

  17. L. plantarum prevents Enteroinvasive Escherichia coli-induced tight junction proteins changes in intestinal epithelial cells

    Directory of Open Access Journals (Sweden)

    Hang Xiaomin

    2009-03-01

    Full Text Available Abstract Background It is increasingly recognized that Lactobacillus plantarum (L. plantarum has the ability to protect against Enteropathogenic Escherichia coli (EPEC-induced damage of the epithelial monolayer barrier function by preventing changes in host cell morphology, attaching/effacing (A/E lesion formation, monolayer resistance, and macromolecular permeability. However, the cellular mechanism involved in this protective effect still remained to be clarified. Methods This study was to investigate the effect of L. plantarum on the changes of Caco-2 cells responding to Enteroinvasive Escherichia coli (EIEC, the permeability of cell monolayer and the transmissivity of dextran, and the distribution and expression of the tight junction (TJ proteins, such as Claudin-1, Occludin, JAM-1 and ZO-1 were examined when infected with EIEC or adhesived of L. plantarum after infection by confocal laser scanning microscopy (CLSM, immunohistochemistry and Western blotting, the cytoskeleton protein F-actin were observed with FITC-phalloidin. Results This study demonstrated that the transepithelial electrical resistance (TER step down and dextran integrated intensity (DII step up with time after infected with EIEC, but after treating with L. plantarum, the changes of TER and DII were improved as compared with EIEC group. L. plantarum prevented the damage of expression and rearrangement of Claudin-1, Occludin, JAM-1 and ZO-1 proteins induced by EIEC, and could ameliorate the injury of cytoskeleton protein F-actin infected with EIEC. Conclusion L. plantarum exerted a protective effect against the damage to integrity of Caco-2 monolayer cells and the structure and distribution of TJ proteins by EIEC infection.

  18. Proteins in load-bearing junctions: the histidine-rich metal-binding protein of mussel byssus.

    Science.gov (United States)

    Zhao, Hua; Waite, J Herbert

    2006-11-28

    Building complex load-bearing scaffolds depends on effective ways of joining functionally different biomacromolecules. The junction between collagen fibers and foamlike adhesive plaques in mussel byssus is robust despite the strikingly dissimilar connected structures. mcfp-4, the matrix protein from this junction, and its presecreted form from the foot tissue of Mytilus californianus were isolated and characterized. mcfp-4 has a mass of approximately 93 kDa as determined by MALDI-TOF mass spectrometry. Its composition is dominated by histidine (22 mol %), but levels of lysine, arginine, and aspartate are also significant. A small amount of 3,4-dihydroxyphenyl-l-alanine (2 mol %) can be detected by amino acid analysis and redox cycling assays. The cDNA-deduced sequence of mcfp-4 reveals multiple variants with highly repetitive internal structures, including approximately 36 tandemly repeated His-rich decapeptides (e.g., HVHTHRVLHK) in the N-terminal half and 16 somewhat more degenerate aspartate-rich undecapeptides (e.g., DDHVNDIAQTA) in the C-terminal half. Incubation of a synthetic peptide based on the His-rich decapeptide with Fe3+, Co2+, Ni2+, Zn2+, and Cu2+ indicates that only Cu is strongly bound. MALDI-TOF mass spectrometry of the peptide modified with diethyl pyrocarbonate before and after Cu binding suggests that histidine residues dominate Cu binding. In contrast, the aspartate-rich undecapeptides preferentially bind Ca2+. mcfp-4 is strategically positioned to function as a macromolecular bifunctional linker by using metal ions to couple its own His-rich domains to the His-rich termini of the preCOLs. Ca2+ may mediate coupling of the C-terminus to other calcium-binding plaque proteins.

  19. Lymphocytes accelerate epithelial tight junction assembly: role of AMP-activated protein kinase (AMPK.

    Directory of Open Access Journals (Sweden)

    Xiao Xiao Tang

    Full Text Available The tight junctions (TJs, characteristically located at the apicolateral borders of adjacent epithelial cells, are required for the proper formation of epithelial cell polarity as well as for sustaining the mucosal barrier to the external environment. The observation that lymphocytes are recruited by epithelial cells to the sites of infection [1] suggests that they may play a role in the modulation of epithelial barrier function and thus contribute to host defense. To test the ability of lymphocytes to modulate tight junction assembly in epithelial cells, we set up a lymphocyte-epithelial cell co-culture system, in which Madin-Darby canine kidney (MDCK cells, a well-established model cell line for studying epithelial TJ assembly [2], were co-cultured with mouse lymphocytes to mimic an infection state. In a typical calcium switch experiment, the TJ assembly in co-culture was found to be accelerated compared to that in MDCK cells alone. This accelaration was found to be mediated by AMP-activated protein kinase (AMPK. AMPK activation was independent of changes in cellular ATP levels but it was found to be activated by the pro-inflammatory cytokine TNF-alpha. Forced suppression of AMPK, either with a chemical inhibitor or by knockdown, abrogated the accelerating effect of lymphocytes on TJ formation. Similar results were also observed in a co-culture with lymphocytes and Calu-3 human airway epithelial cells, suggesting that the activation of AMPK may be a general mechanism underlying lymphocyte-accelerated TJ assembly in different epithelia. These results suggest that signals from lymphocytes, such as cytokines, facilitate TJ assembly in epithelial cells via the activation of AMPK.

  20. The Werner and Bloom syndrome proteins help resolve replication blockage by converting (regressed) holliday junctions to functional replication forks.

    Science.gov (United States)

    Machwe, Amrita; Karale, Rajashree; Xu, Xioahua; Liu, Yilun; Orren, David K

    2011-08-16

    Cells cope with blockage of replication fork progression in a manner that allows DNA synthesis to be completed and genomic instability minimized. Models for resolution of blocked replication involve fork regression to form Holliday junction structures. The human RecQ helicases WRN and BLM (deficient in Werner and Bloom syndromes, respectively) are critical for maintaining genomic stability and thought to function in accurate resolution of replication blockage. Consistent with this notion, WRN and BLM localize to sites of blocked replication after certain DNA-damaging treatments and exhibit enhanced activity on replication and recombination intermediates. Here we examine the actions of WRN and BLM on a special Holliday junction substrate reflective of a regressed replication fork. Our results demonstrate that, in reactions requiring ATP hydrolysis, both WRN and BLM convert this Holliday junction substrate primarily to a four-stranded replication fork structure, suggesting they target the Holliday junction to initiate branch migration. In agreement, the Holliday junction binding protein RuvA inhibits the WRN- and BLM-mediated conversion reactions. Importantly, this conversion product is suitable for replication with its leading daughter strand readily extended by DNA polymerases. Furthermore, binding to and conversion of this Holliday junction are optimal at low MgCl(2) concentrations, suggesting that WRN and BLM preferentially act on the square planar (open) conformation of Holliday junctions. Our findings suggest that, subsequent to fork regression events, WRN and/or BLM could re-establish functional replication forks to help overcome fork blockage. Such a function is highly consistent with phenotypes associated with WRN- and BLM-deficient cells.

  1. Autophagy enhances intestinal epithelial tight junction barrier function by targeting claudin-2 protein degradation.

    Science.gov (United States)

    Nighot, Prashant K; Hu, Chien-An Andy; Ma, Thomas Y

    2015-03-13

    Autophagy is an intracellular degradation pathway and is considered to be an essential cell survival mechanism. Defects in autophagy are implicated in many pathological processes, including inflammatory bowel disease. Among the innate defense mechanisms of intestinal mucosa, a defective tight junction (TJ) barrier has been postulated as a key pathogenic factor in the causation and progression of inflammatory bowel disease by allowing increased antigenic permeation. The cross-talk between autophagy and the TJ barrier has not yet been described. In this study, we present the novel finding that autophagy enhances TJ barrier function in Caco-2 intestinal epithelial cells. Nutrient starvation-induced autophagy significantly increased transepithelial electrical resistance and reduced the ratio of sodium/chloride paracellular permeability. Nutrient starvation reduced the paracellular permeability of small-sized urea but not larger molecules. The role of autophagy in the modulation of paracellular permeability was confirmed by pharmacological induction as well as pharmacological and genetic inhibition of autophagy. Consistent with the autophagy-induced reduction in paracellular permeability, a marked decrease in the level of the cation-selective, pore-forming TJ protein claudin-2 was observed after cell starvation. Starvation reduced the membrane presence of claudin-2 and increased its cytoplasmic, lysosomal localization. Therefore, our data show that autophagy selectively reduces epithelial TJ permeability of ions and small molecules by lysosomal degradation of the TJ protein claudin-2.

  2. The RecA/RAD51 protein drives migration of Holliday junctions via polymerization on DNA.

    Science.gov (United States)

    Rossi, Matthew J; Mazina, Olga M; Bugreev, Dmitry V; Mazin, Alexander V

    2011-04-19

    The Holliday junction (HJ), a cross-shaped structure that physically links the two DNA helices, is a key intermediate in homologous recombination, DNA repair, and replication. Several helicase-like proteins are known to bind HJs and promote their branch migration (BM) by translocating along DNA at the expense of ATP hydrolysis. Surprisingly, the bacterial recombinase protein RecA and its eukaryotic homologue Rad51 also promote BM of HJs despite the fact they do not bind HJs preferentially and do not translocate along DNA. RecA/Rad51 plays a key role in DNA double-stranded break repair and homologous recombination. RecA/Rad51 binds to ssDNA and forms contiguous filaments that promote the search for homologous DNA sequences and DNA strand exchange. The mechanism of BM promoted by RecA/RAD51 is unknown. Here, we demonstrate that cycles of RecA/Rad51 polymerization and dissociation coupled with ATP hydrolysis drives the BM of HJs.

  3. Adaptive evolution of tight junction protein claudin-14 in echolocating whales.

    Science.gov (United States)

    Xu, Huihui; Liu, Yang; He, Guimei; Rossiter, Stephen J; Zhang, Shuyi

    2013-11-10

    Toothed whales and bats have independently evolved specialized ultrasonic hearing for echolocation. Recent findings have suggested that several genes including Prestin, Tmc1, Pjvk and KCNQ4 appear to have undergone molecular adaptations associated with the evolution of this ultrasonic hearing in mammals. Here we studied the hearing gene Cldn14, which encodes the claudin-14 protein and is a member of tight junction proteins that functions in the organ of Corti in the inner ear to maintain a cationic gradient between endolymph and perilymph. Particular mutations in human claudin-14 give rise to non-syndromic deafness, suggesting an essential role in hearing. Our results uncovered two bursts of positive selection, one in the ancestral branch of all toothed whales and a second in the branch leading to the delphinid, phocoenid and ziphiid whales. These two branches are the same as those previously reported to show positive selection in the Prestin gene. Furthermore, as with Prestin, the estimated hearing frequencies of whales significantly correlate with numbers of branch-wise non-synonymous substitutions in Cldn14, but not with synonymous changes. However, in contrast to Prestin, we found no evidence of positive selection in bats. Our findings from Cldn14, and comparisons with Prestin, strongly implicate multiple loci in the acquisition of echolocation in cetaceans, but also highlight possible differences in the evolutionary route to echolocation taken by whales and bats. © 2013.

  4. Characterization of the tight junction protein ZO-2 localized at the nucleus of epithelial cells.

    Science.gov (United States)

    Jaramillo, Blanca Estela; Ponce, Arturo; Moreno, Jacqueline; Betanzos, Abigail; Huerta, Miriam; Lopez-Bayghen, Esther; Gonzalez-Mariscal, Lorenza

    2004-07-01

    ZO-2 is a MAGUK protein that in confluent epithelial sheets localizes at tight junctions (TJ) whereas in sparse cultures accumulates in clusters at the nucleus. Here, we have characterized several nuclear properties of ZO-2. We observe that ZO-2 is present in the nuclear matrix and co-immunoprecipitates with lamin B(1) and actin from the nuclei of sparse cultures. We show that ZO-2 presents several NLS at its amino region, that when deleted, diminish the nuclear import of the ZO-2 amino segment and impair the ability of the region to regulate the transcriptional activity of promoters controlled by AP-1. Several RS repeats are detected in the ZO-2 amino segment, however, their deletion does not preclude the display of a speckled nuclear pattern. ZO-2 displays two putative NES. However, only the second one appears to be functional, as when conjugated to ovalbumin (OV), it is able to translocate this protein from the nucleus to the cytoplasm in a leptomycin B-sensitive way.

  5. The prognostic value of E-cadherin and the cadherin-associated molecules alpha-, beta-, gamma-catenin and p120ctn in prostate cancer specific survival: a long-term follow-up study.

    NARCIS (Netherlands)

    Oort, I.M. van; Tomita, K.; Bokhoven, A. van; Bussemakers, M.J.G.; Kiemeney, L.A.L.M.; Karthaus, H.F.M.; Witjes, J.A.; Schalken, J.A.

    2007-01-01

    OBJECTIVES: To determine the value of loss of expression of E-cadherin and cadherin associated molecules as prognostic markers for prostate cancer patients in a long-term follow-up study. METHODS: Sixty-five prostate cancer specimens, obtained from patients with different stages of prostate cancer w

  6. EMP-induced alterations of tight junction protein expression and disruption of the blood-brain barrier.

    Science.gov (United States)

    Ding, Gui-Rong; Qiu, Lian-Bo; Wang, Xiao-Wu; Li, Kang-Chu; Zhou, Yong-Chun; Zhou, Yan; Zhang, Jie; Zhou, Jia-Xing; Li, Yu-Rong; Guo, Guo-Zhen

    2010-07-15

    The blood-brain barrier (BBB) is critical to maintain cerebral homeostasis. In this study, we examined the effects of exposure to electromagnetic pulse (EMP) on the functional integrity of BBB and, on the localization and expression of tight junction (TJ) proteins (occludin and ZO-1) in rats. Animals were sham or whole-body exposed to EMP at 200 kV/m for 400 pulses. The permeability of BBB in rat cerebral cortex was examined by using Evans Blue (EB) and lanthanum nitrate as vascular tracers. The localization and expression of TJ proteins were assessed by western blot and immunofluorescence analysis, respectively. The data indicated that EMP exposure caused: (i) increased permeability of BBB, and (ii) altered localization as well as decreased levels of TJ protein ZO-1. These results suggested that the alteration of ZO-1 may play an important role in the disruption of tight junctions, which may lead to dysfunction of BBB after EMP exposure.

  7. In Vitro and In Vivo Effects of Phenethyl Isothiocyanate Treatment on Vimentin Protein Expression in Cancer Cells

    OpenAIRE

    Sakao, Kozue; Hahm, Eun-Ryeong; Singh, Shivendra V.

    2013-01-01

    We have shown previously that cancer prevention by cruciferous vegetable constituent phenethyl isothiocyanate (PEITC) in a transgenic mouse model of prostate cancer is associated with induction of E-cadherin protein expression. Because suppression of E-cadherin protein concomitant with induction of mesenchymal markers (e.g., vimentin) is a biochemical hallmark of epithelial-mesenchymal transition, a process implicated in cancer metastasis, we hypothesized that PEITC treatment was likely to su...

  8. Comparative analysis of theophylline and cholera toxin in rat colon reveals an induction of sealing tight junction proteins.

    Science.gov (United States)

    Markov, Alexander G; Falchuk, Evgeny L; Kruglova, Natalia M; Rybalchenko, Oksana V; Fromm, Michael; Amasheh, Salah

    2014-11-01

    Claudin tight junction proteins have been identified to primarily determine intestinal epithelial barrier properties. While functional contribution of single claudins has been characterized in detail, information on the interplay with secretory mechanisms in native intestinal epithelium is scarce. Therefore, effects of cholera toxin and theophylline on rat colon were analyzed, including detection of sealing claudins. Tissue specimens were stripped off submucosal tissue layers and mounted in Ussing chambers, and short-circuit current (ISC) and transepithelial resistance (TER) were recorded. In parallel, expression and localization of claudins was analyzed and histological studies were performed employing hematoxylin-eosin staining and light and electron microscopy. Theophylline induced a strong increase of ISC in colon tissue specimens. In parallel, a decrease of TER was observed. In contrast, cholera toxin did not induce a significant increase of ISC, whereas an increase of TER was detected after 120 min. Western blots of membrane fractions revealed an increase of claudin-3 and -4 after incubation with cholera toxin, and theophylline induced an increase of claudin-4. In accordance, confocal laser-scanning microscopy exhibited increased signals of claudin-3 and -4 after incubation with cholera toxin, and increased signals of claudin-4 after incubation with theophylline, within tight junction complexes. Morphological analyses revealed no general changes of tight junction complexes, but intercellular spaces were markedly widened after incubation with cholera toxin and theophylline. We conclude that cholera toxin and theophylline have different effects on sealing tight junction proteins in native colon preparations, which may synergistically contribute to transport functions, in vitro.

  9. Acidic bile salts modulate the squamous epithelial barrier function by modulating tight junction proteins.

    Science.gov (United States)

    Chen, Xin; Oshima, Tadayuki; Tomita, Toshihiko; Fukui, Hirokazu; Watari, Jiro; Matsumoto, Takayuki; Miwa, Hiroto

    2011-08-01

    Experimental models for esophageal epithelium in vitro either suffer from poor differentiation or complicated culture systems. An air-liquid interface system with normal human bronchial epithelial cells can serve as a model of esophageal-like squamous epithelial cell layers. Here, we explore the influence of bile acids on barrier function and tight junction (TJ) proteins. The cells were treated with taurocholic acid (TCA), glycocholic acid (GCA), or deoxycholic acid (DCA) at different pH values, or with pepsin. Barrier function was measured by transepithelial electrical resistance (TEER) and the diffusion of paracellular tracers (permeability). The expression of TJ proteins, including claudin-1 and claudin-4, was examined by Western blotting of 1% Nonidet P-40-soluble and -insoluble fractions. TCA and GCA dose-dependently decreased TEER and increased paracellular permeability at pH 3 after 1 h. TCA (4 mM) or GCA (4 mM) did not change TEER and permeability at pH 7.4 or pH 4. The combination of TCA and GCA at pH 3 significantly decreased TEER and increased permeability at lower concentrations (2 mM). Pepsin (4 mg/ml, pH 3) did not have any effect on barrier function. DCA significantly decreased the TEER and increased permeability at pH 6, a weakly acidic condition. TCA (4 mM) and GCA (4 mM) significantly decreased the insoluble fractions of claudin-1 and claudin-4 at pH 3. In conclusion, acidic bile salts disrupted the squamous epithelial barrier function partly by modulating the amounts of claudin-1 and claudin-4. These results provide new insights for understanding the role of TJ proteins in esophagitis.

  10. A role for tight junction-associated MARVEL proteins in larval sea lamprey (Petromyzon marinus) osmoregulation.

    Science.gov (United States)

    Kolosov, Dennis; Bui, Phuong; Donini, Andrew; Wilkie, Mike P; Kelly, Scott P

    2017-08-10

    This study reports on tight junction-associated MARVEL proteins of larval sea lamprey (Petromyzon marinus) and their potential role in ammocoete osmoregulation. Two Occludin isoforms (designated Ocln and Ocln-a) and a tricellulin (Tric) were identified. Transcripts encoding ocln, ocln-a, and tric were broadly expressed in larval lamprey, with greatest abundance of ocln in gut, liver and kidney, ocln-a in the gill and skin, and tric in the kidney. Ocln and Ocln-a resolved as ∼63 kDa and ∼35 kDa MW proteins respectively while Tric resolved as a ∼50 kDa protein. Ocln immunolocalized to the gill vasculature and in gill mucous cells while Ocln-a localized to the gill pouch and gill epithelium. Both Ocln and Ocln-a localized in the nephron, the epidermis and the luminal side of the gut. In branchial tissue, Tric exhibited punctate localization, consistent with its presence at regions of tricellular contact. Following ion-poor water (IPW) acclimation of ammocoetes, serum [Na(+)] and [Cl(-)] reduced, but not [Ca(++)], and carcass moisture content increased. In association, Ocln abundance increased in skin and kidney, but reduced in gill of IPW-acclimated ammocoetes while Ocln-a abundance reduced in the kidney only. Tric abundance increased in the gill. Region-specific alterations in ocln, ocln-a and tric mRNA abundance was also observed in the gut. Data support a role for Ocln, Ocln-a and Tric in the osmoregulatory strategies of a basal vertebrate. © 2017. Published by The Company of Biologists Ltd.

  11. 沉默信息调节因子2相关酶1在贲门癌中表达的意义及相互关系%Expressions of SIRT 1, E-cadherin and MLH 1 in gastric cardia carcinoma and their relationship

    Institute of Scientific and Technical Information of China (English)

    冯安宁; 樊祥山; 黄勤; 章宜芬; 叶庆; 吴鸿雁; 杨军; 张丽华

    2011-01-01

    目的 沉默信息调节因子2相关酶l( silent mating type information regulation 2 homolog 1,SIRT 1)是活性依赖烟酰胺腺嘌呤二核苷酸( nicotinamide adenine dinucleotide,NAD)的去乙酰化酶,可能参与某些肿瘤的形成及进展,并对多种肿瘤相关基因的蛋白活性及基因沉默的调控中起重要作用.文中研究SIRT1及上皮钙黏蛋白(epithelial cad-herin,E-cadherin)和错配修复蛋白1(Mutl homoolog 1,MLH1)在贲门癌中表达的临床病理学意义及相互关系. 方法 应用组织芯片技术和免疫组化EnVision二步法检测176例贲门癌患者癌组织中SIRT1、E-cadherin、MLH 1蛋白的表达.结果 SIRT1表达阳性率与淋巴结转移数目及TNM分期呈正相关.E-cadherin和MLH 1表达与淋巴结转移数目、TNM分期呈负相关.90例有随访资料病例中,SIRT1阳性患者3年生存率及平均生存时间显著低于SIRT1阴性患者.E-cadherin强阳性表达患者3年生存率及平均生存时间显著高于弱阳性表达患者,MLH 1阳性表达患者的3年生存率及平均生存时间高于MHLI阴性患者,差异均有统计学意义. 结论 贲门癌中SIRT 1阳性表达与肿瘤恶性程度正相关.E-cadherin表达程度及MLH 1阳性表达与肿瘤恶性程度负相关,SIRT 1可能通过E-cadherin、MLH 1等抑癌基因的沉默作用促进贲门癌的形成,影响其恶性生物学行为.%Objective SIRT1 is a NAD+ ( nicotinmide nicotinamide adenine dinucleotide) -dependent deacetylase, which may be involved in the formation and progression of many types of carcinoma, and plays an important role in regulating protein function and gene silencing of certain tumor-related genes. The objective of the research is to investigate the clinicopathological significance of the expressions of SIRT1, MLH1 and E-cadherin in gastric cardia carcinoma and their relationship. Methods We detected the ex-pressiond of SIRT 1, MLH 1 and E-cadherin proteins in the gastric cardia carcinoma tissues of 176

  12. Characterization of the structural and protein recognition properties of hybrid PNA-DNA four-way junctions.

    Science.gov (United States)

    Iverson, Douglas; Serrano, Crystal; Brahan, Ann Marie; Shams, Arik; Totsingan, Filbert; Bell, Anthony J

    2015-12-01

    The objective of this study is to evaluate the structure and protein recognition properties of hybrid four-way junctions (4WJs) composed of DNA and peptide nucleic acid (PNA) strands. We compare a classic immobile DNA junction, J1, vs. six PNA-DNA junctions, including a number with blunt DNA ends and multiple PNA strands. Circular dichroism (CD) analysis reveals that hybrid 4WJs are composed of helices that possess structures intermediate between A- and B-form DNA, the apparent level of A-form structure correlates with the PNA content. The structure of hybrids that contain one PNA strand is sensitive to Mg(+2). For these constructs, the apparent B-form structure and conformational stability (Tm) increase in high Mg(+2). The blunt-ended junction, b4WJ-PNA3, possesses the highest B-form CD signals and Tm (40.1 °C) values vs. all hybrids and J1. Protein recognition studies are carried out using the recombinant DNA-binding protein, HMGB1b. HMGB1b binds the blunt ended single-PNA hybrids, b4WJ-PNA1 and b4WJ-PNA3, with high affinity. HMGB1b binds the multi-PNA hybrids, 4WJ-PNA1,3 and b4WJ-PNA1,3, but does not form stable protein-nucleic acid complexes. Protein interactions with hybrid 4WJs are influenced by the ratio of A- to B-form helices: hybrids with helices composed of higher levels of B-form structure preferentially associate with HMGB1b.

  13. Role of calcium and vesicle-docking proteins in remobilising dormant neuromuscular junctions in desert frogs.

    Science.gov (United States)

    Lavidis, Nickolas A; Hudson, Nicholas J; Choy, Peng T; Lehnert, Sigrid A; Franklin, Craig E

    2008-01-01

    Despite prolonged immobility the desert frog, Cyclorana alboguttata, suffers little impairment in muscle function. To determine compensatory mechanisms at neuromuscular junctions, transmitter release was examined along primary terminals in C. alboguttata iliofibularis muscle. Using extracellular recording we found the amplitudes of evoked endplate currents were significantly smaller in dormant frogs. In active frogs we identified two negatively sloping proximal-distal gradients of transmitter frequency and quantal content; a shallow proximal-distal gradient with low probability of transmitter release (0.6). During aestivation, only a shallow gradient was identified. The high probability release sites in control frogs were inhibited during aestivation by a mechanism that could be reversed by (1) increasing the extracellular calcium concentration, and (2) increasing the frequency of stimulation. This suggests that transmitter vesicles are available during aestivation but not released. We quantified expression of messenger RNA transcripts coding for the transmitter vesicle-docking proteins synaptotagmin 1, syntaxin 1B and UNC-13. All three were rare transcripts maintained at control values during aestivation. Neuromuscular remobilisation after dormancy in C. alboguttata is more likely a product of rapidly reversible physiologic mechanisms than reorganisations of the neuromuscular transcriptome.

  14. Cloning, mapping and mutation analysis of human gene GJB5 encoding gap junction protein b-5

    Institute of Scientific and Technical Information of China (English)

    XIA; Jiahui; (夏家辉); ZHENG; Duo; (郑多),; TANG; Dongsheng; (唐冬生); DAI; Heping; (戴和平); PAN; Qian; (潘乾); LONG; Zhigao; (龙志高); LIAO; Xiaodong; (廖晓东)

    2001-01-01

    By homologous EST searching and nested PCR a new human gene GJB5 encoding gap junction protein b-5 was identified. GJB5 was genetically mapped to human chromosome 1p33-p35 by FISH. RT-PCR revealed that it was expressed in skin, placenta and fetal skin. DNA sequencing of GJB5 was carried out in 142 patients with sensorineural hearing impairment and probands of 36 families with genetic diseases, including erythrokeratodermia (5 families), Charcot-Marie-Tooth disease (13), ptosis (4), and retinitis pigmentosa and deafness (14). Two missense mutations (686A→G, H229R; 25C→T, L9F) were detected in two sensorineural hearing impairment families. A heterologous deletion of 18 bp within intron was found in 3 families with heredity hearing impairment, and in one of the 3 families, a missense mutation (R265P) was identified also. But the deletion and missense mutation seemed not segregating with hearing impairment in the family. No abnormal mRNA or mRNA expression was detected in deletion carriers by RT-PCR analysis in skin tissue. Mutation analysis in 199 unaffected individuals revealed that two of them were carriers with the same 18 bp deletion.

  15. Cloning, mapping and mutation analysis of human gene GJB5 encoding gap junction protein b-5

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    By homologous EST searching and nested PCR a new human gene GJB5encoding gap junction protein b-5 was identified. GJB5 was genetically mapped to human chromosome 1p33-p35 by FISH. RT-PCR revealed that it was expressed in skin, placenta and fetal skin. DNA sequencing of GJB5 was carried out in 142 patients with sensorineural hearing impairment and probands of 36 families with genetic diseases, including erythrokeratodermia (5 families), Charcot-Marie-Tooth disease (13), ptosis (4), and retinitis pigmentosa and deafness (14). Two missense mutations (686A→G, H229R; 25C→T, L9F) were detected in two sensorineural hearing impairment families. A heterologous deletion of 18 bp within intron was found in 3 families with heredity hearing impairment, and in one of the 3 families, a missense mutation (R265P) was identified also. But the deletion and missense mutation seemed not segregating with hearing impairment in the family. No abnormal mRNA or mRNA expression was detected in deletion carriers by RT-PCR analysis in skin tissue. Mutation analysis in 199 unaffected individuals revealed that two of them were carriers with the same 18 bp deletion.

  16. Interleukin-6, desmosome and tight junction protein expression levels in reflux esophagitis-affected mucosa

    Institute of Scientific and Technical Information of China (English)

    Fei-Yue Li; Yan Li

    2009-01-01

    AIM: To investigate the correlation between the expression levels of interleukin (IL)-6 and proteins in tight junctions (TJs) in the esophageal mucosa of rats modeling different types of reflux esophagitis (RE), and the ability of aluminum phosphate to protect against RE-induced mucosal damage via these proteins. METHODS: Male SPF Wistar rats aged 56 d were divided randomly into acid RE, alkaline RE, mixed RE, and control groups. Various surgical procedures were performed to establish rat models of acid RE. At 14 d after the procedure, some of the rats started aluminum phosphate treatment. Transmission electron microscopy (TEM) was used to observe the morphological features of TJs and desmosomes in the esophageal epithelium. Immunohistochemical methods and Western blotting were used to measure expression of claudin 1, occludin, ZO-1, JAM-1, DSG-1 and IL-6; reverse transcription polymerase chain reaction (RTPCR) was used to measure expression of mRNA of claudin 1, occludin, ZO-1, JAM-1, DSG-1 and IL-6. RESULTS: At day 14 after the procedures, an RE model was established in all subsequently sacrificed rats of groups A, B and C. By both gross and microscopic observation, the mucosa was damaged and thickened as the disease progressed. With TEM observation, a widened intercellular space was noticed, with significantly fewer desmosomes. Immunohistochemistry showed significantly higher levels of all proteins in all RE models compared to control rats at 3 d after operation (65.5% ± 25.6% vs 20.5% ± 2.1%, P 0.05, treated vs untreated, respectively). These levels increased in the rat with alkaline RE, and this increase was accompanied by continued hyperplasia in comparison with controls (85.5% ± 25.6% vs 20.5% ± 2.1%, P < 0.05, respectively). Furthermore, the expression of TJ proteins was not correlated significantly with that of IL-6 in this group. CONCLUSION: These findings indicate that TJ proteins are highly expressed as an early molecular event involved in RE

  17. Analysis of the distribution and expression of claudin-1 tight junction protein in the oral cavity.

    Science.gov (United States)

    Ouban, Abderrahman; Ahmed, Atif

    2015-07-01

    Claudins are the main sealing proteins of the intercellular tight junctions and play an important role in cancer cell progression and dissemination. The authors have previously shown that overexpression of claudin-1 is associated with angiolymphatic and perineural invasion, consistent with aggressive tumor behavior and with advanced stage disease in oral squamous cell carcinomas (OSCCs). Our goal in this study was to examine claudin-1 expression in a tissue microarray of OSCCs taken from multiple sites within the oral cavity. This study examined and compared the expression of claudin-1 by immunohistochemistry in 60 tissue samples (49 OSCCs and 10 cases of non-neoplastic tissue, single core per case) were analyzed for claudin-1 expression by immunohistochemistry. The tumors included SCCs from the tongue (n=28), the cheek (n=9), gingival (n=4), lip (n=3), and oral cavity (n=5). Nonmalignant normal oral mucosa from the tongue (unmatched cases, n=2). Cancer adjacent tissue samples were taken from the tongue (n=6), gingival (n=2), and palate (n=1). This study demonstrates the expression of claudin-1 protein across a sample of OSCCs originating from multiple locations in the oral cavity. The highest expression of claudin-1 was observed in well-differentiated OSCCs, whereas poorly differentiated OSCCs exhibited mostly negative staining for claudin-1. In addition, we hereby report differential pattern of expression among tumors of different sites within the oral cavity, and between benign and cancerous samples. Our understanding of the exact function and role of claudin-1 in tumorigenesis is expanding exponentially.

  18. Ischaemia-induced autophagy leads to degradation of gap junction protein connexin43 in cardiomyocytes.

    Science.gov (United States)

    Martins-Marques, Tania; Catarino, Steve; Zuzarte, Monica; Marques, Carla; Matafome, Paulo; Pereira, Paulo; Girão, Henrique

    2015-04-15

    GJIC (gap junction intercellular communication) between cardiomyocytes is essential for synchronous heart contraction and relies on Cx (connexin)-containing channels. Increased breakdown of Cx43 has been often associated with various cardiac diseases. However, the mechanisms whereby Cx43 is degraded in ischaemic heart remain unknown. The results obtained in the present study, using both HL-1 cells and organotypic heart cultures, show that simulated ischaemia induces degradation of Cx43 that can be prevented by chemical or genetic inhibitors of autophagy. Additionally, ischaemia-induced degradation of Cx43 results in GJIC impairment in HL-1 cells, which can be restored by autophagy inhibition. In cardiomyocytes, ubiquitin signals Cx43 for autophagic degradation, through the recruitment of the ubiquitin-binding proteins Eps15 (epidermal growth factor receptor substrate 15) and p62, that assist in Cx43 internalization and targeting to autophagic vesicles, via LC3 (light chain 3). Moreover, we establish that degradation of Cx43 in ischaemia or I/R (ischaemia/reperfusion) relies upon different molecular players. Indeed, degradation of Cx43 during early periods of ischaemia depends on AMPK (AMP-activated protein kinase), whereas in late periods of ischaemia and I/R Beclin 1 is required. In the Langendorff-perfused heart, Cx43 is dephosphorylated in ischaemia and degraded during I/R, where Cx43 degradation correlates with autophagy activation. In summary, the results of the present study provide new evidence regarding the molecular mechanisms whereby Cx43 is degraded in ischaemia, which may contribute to the development of new strategies that aim to preserve GJIC and cardiac function in ischaemic heart.

  19. Pharmacoproteomic analysis reveals that metapristone (RU486 metabolite) intervenes E-cadherin and vimentin to realize cancer metastasis chemoprevention.

    Science.gov (United States)

    Yu, Suhong; Yan, Cuicui; Yang, Xingtian; He, Sudang; Liu, Jian; Qin, Chongtao; Huang, Chuanzhong; Lu, Yusheng; Tian, Zhongping; Jia, Lee

    2016-03-02

    Metapristone is the most predominant biological active metabolite of mifepristone, and being developed as a novel cancer metastasis chemopreventive agent by us. Despite its prominent metastasis chemopreventive effect, the underlying mechanism remains elusive. Our study, for the first time, demonstrated that metapristone had the ability to prevent breast cancer cells from migration, invasion, and interfere with their adhesion to endothelial cells. To explore the underlying mechanism of metapristone, we employed the iTRAQ technique to assess the effect of metapristone on MDA-MB-231 cells. In total, 5,145 proteins were identified, of which, 311 proteins showed significant differences in metapristone-treated cells compared to the control group (P-value metastasis chemoprevention is through intervening the EMT-related signaling pathways.

  20. Volatile Anesthetics Influence Blood-Brain Barrier Integrity by Modulation of Tight Junction Protein Expression in Traumatic Brain Injury

    OpenAIRE

    Thal, Serge C.; Clara Luh; Eva-Verena Schaible; Ralph Timaru-Kast; Jana Hedrich; Luhmann, Heiko J.; Kristin Engelhard; Zehendner, Christoph M.

    2012-01-01

    Disruption of the blood-brain barrier (BBB) results in cerebral edema formation, which is a major cause for high mortalityrnafter traumatic brain injury (TBI). As anesthetic care is mandatory in patients suffering from severe TBI it may be importantrnto elucidate the effect of different anesthetics on cerebral edema formation. Tight junction proteins (TJ) such as zonularnoccludens-1 (ZO-1) and claudin-5 (cl5) play a central role for BBB stability. First, the influence of the volatile anesthet...

  1. Inhibition of Akt activity induces the mesenchymal-to-epithelial reverting transition with restoring E-cadherin expression in KB and KOSCC-25B oral squamous cell carcinoma cells

    Directory of Open Access Journals (Sweden)

    Hong Sam-Pyo

    2009-02-01

    Full Text Available Abstract Background The Akt/PKB family of kinases is frequently activated in human cancers, including oral squamous cell carcinoma (OSCC. Akt-induced epithelial-to-mesenchymal transition (EMT involves downregulation of E-cadherin, which appears to result from upregulation of the transcription repressor Snail. Recently, it was proposed that carcinoma cells, especially in metastatic sites, could acquire the mesenchymal-to-epithelial reverting transition (MErT in order to adapt the microenvironments and re-expression of E-cadherin be a critical indicator of MErT. However, the precise mechanism and biologic or clinical importance of the MErT in cancers have been little known. This study aimed to investigate whether Akt inhibition would restore the expression of E-cadherin and β-catenin, reduce that of Vimentin, and induce the MErT in OSCC cells with low or negative expression of E-cadherin. We also investigate whether inhibition of Akt activity would affect the E-cadherin repressors and signaling molecules like NF-κB, ERK, and p38. Methods We screened several OSCC cell lines in order to select suitable cell line models for inducing MErT, using immunoblotting and methylation specific-PCR. We examined whether Akt inhibitor phosphatidylinositol ether lipid analogues (PIA treatment would restore the expression of E-cadherin and β-catenin, reduce that of Vimentin, and induce the MErT in KB and KOSCC-25B cells using RT-PCR, immunoblotting, immunofluorescence analysis, and in vitro migration assay. We also investigated whether inhibition of Akt activity would affect the E-cadherin repressors, including Snail, Twist, and SIP-1/ZEB-2 and signaling molecules like NF-κB, ERK, JNK, and p38 using RT-PCR, immunoblotting, and immunofluorescence analysis. Results Of the 7 OSCC cell lines, KB and KOSCC-25B showed constitutively activated phosphorylated Akt and low or negative expression of E-cadherin. Inhibition of Akt activity by PIA decreased NF-κB signaling

  2. Discovery of a junctional epitope antibody that stabilizes IL-6 and gp80 protein:protein interaction and modulates its downstream signaling

    Science.gov (United States)

    Adams, Ralph; Burnley, Rebecca J.; Valenzano, Chiara R.; Qureshi, Omar; Doyle, Carl; Lumb, Simon; del Carmen Lopez, Maria; Griffin, Robert; McMillan, David; Taylor, Richard D.; Meier, Chris; Mori, Prashant; Griffin, Laura M.; Wernery, Ulrich; Kinne, Jörg; Rapecki, Stephen; Baker, Terry S.; Lawson, Alastair D. G.; Wright, Michael; Ettorre, Anna

    2017-01-01

    Protein:protein interactions are fundamental in living organism homeostasis. Here we introduce VHH6, a junctional epitope antibody capable of specifically recognizing a neo-epitope when two proteins interact, albeit transiently, to form a complex. Orthogonal biophysical techniques have been used to prove the “junctional epitope” nature of VHH6, a camelid single domain antibody recognizing the IL-6–gp80 complex but not the individual components alone. X-ray crystallography, HDX-MS and SPR analysis confirmed that the CDR regions of VHH6 interact simultaneously with IL-6 and gp80, locking the two proteins together. At the cellular level, VHH6 was able to alter the response of endothelial cells to exogenous IL-6, promoting a sustained STAT3 phosphorylation signal, an accumulation of IL-6 in vesicles and an overall pro-inflammatory phenotype supported further by transcriptomic analysis. Junctional epitope antibodies, like VHH6, not only offer new opportunities in screening and structure-aided drug discovery, but could also be exploited as therapeutics to modulate complex protein:protein interactions. PMID:28134246

  3. Cdc42-dependent Modulation of Tight Junctions and Membrane Protein Traffic in Polarized Madin-Darby Canine Kidney Cells

    Science.gov (United States)

    Rojas, Raul; Ruiz, Wily G.; Leung, Som-Ming; Jou, Tzuu-Shuh; Apodaca, Gerard

    2001-01-01

    Polarized epithelial cells maintain the asymmetric composition of their apical and basolateral membrane domains by at least two different processes. These include the regulated trafficking of macromolecules from the biosynthetic and endocytic pathway to the appropriate membrane domain and the ability of the tight junction to prevent free mixing of membrane domain-specific proteins and lipids. Cdc42, a Rho family GTPase, is known to govern cellular polarity and membrane traffic in several cell types. We examined whether this protein regulated tight junction function in Madin-Darby canine kidney cells and pathways that direct proteins to the apical and basolateral surface of these cells. We used Madin-Darby canine kidney cells that expressed dominant-active or dominant-negative mutants of Cdc42 under the control of a tetracycline-repressible system. Here we report that expression of dominant-active Cdc42V12 or dominant-negative Cdc42N17 altered tight junction function. Expression of Cdc42V12 slowed endocytic and biosynthetic traffic, and expression of Cdc42N17 slowed apical endocytosis and basolateral to apical transcytosis but stimulated biosynthetic traffic. These results indicate that Cdc42 may modulate multiple cellular pathways required for the maintenance of epithelial cell polarity. PMID:11514615

  4. Rescue of perfluorooctanesulfonate (PFOS)-mediated Sertoli cell injury by overexpression of gap junction protein connexin 43

    Science.gov (United States)

    Li, Nan; Mruk, Dolores D.; Chen, Haiqi; Wong, Chris K. C.; Lee, Will M.; Cheng, C. Yan

    2016-07-01

    Perfluorooctanesulfonate (PFOS) is an environmental toxicant used in developing countries, including China, as a stain repellent for clothing, carpets and draperies, but it has been banned in the U.S. and Canada since the late 2000s. PFOS perturbed the Sertoli cell tight junction (TJ)-permeability barrier, causing disruption of actin microfilaments in cell cytosol, perturbing the localization of cell junction proteins (e.g., occluden-ZO-1, N-cadherin-ß-catenin). These changes destabilized Sertoli cell blood-testis barrier (BTB) integrity. These findings suggest that human exposure to PFOS might induce BTB dysfunction and infertility. Interestingly, PFOS-induced Sertoli cell injury associated with a down-regulation of the gap junction (GJ) protein connexin43 (Cx43). We next investigated if overexpression of Cx43 in Sertoli cells could rescue the PFOS-induced cell injury. Indeed, overexpression of Cx43 in Sertoli cells with an established TJ-barrier blocked the disruption in PFOS-induced GJ-intercellular communication, resulting in the re-organization of actin microfilaments, which rendered them similar to those in control cells. Furthermore, cell adhesion proteins that utilized F-actin for attachment became properly distributed at the cell-cell interface, resealing the disrupted TJ-barrier. In summary, Cx43 is a good target that might be used to manage PFOS-induced reproductive dysfunction.

  5. Gap junctional protein Cx43 is involved in the communication between extracellular vesicles and mammalian cells

    NARCIS (Netherlands)

    Soares, Ana Rosa; Martins-Marques, Tania; Ribeiro-Rodrigues, Teresa; Ferreira, Joao Vasco; Catarino, Steve; Pinho, Maria Joao; Zuzarte, Monica; Anjo, Sandra Isabel; Manadas, Bruno; Sluijter, Joost P. G.; Pereira, Paulo; Girao, Henrique

    2015-01-01

    Intercellular communication is vital to ensure tissue and organism homeostasis and can occur directly, between neighbour cells via gap junctions (GJ), or indirectly, at longer distances, through extracellular vesicles, including exosomes. Exosomes, as intercellular carriers of messenger molecules, m

  6. Paracellin-1, a renal tight junction protein required for paracellular Mg2+ resorption

    NARCIS (Netherlands)

    Simon, DB; Lu, Y; Choate, KA; Velazquez, H; Al-Sabban, E; Praga, M; Casari, C; Bettinelli, A; Colussi, C; Rodriguez-Soriano, J; McCredie, D; Milford, D; Sanjad, S; Lifton, RP

    1999-01-01

    Epithelia permit selective and regulated flux from apical to basolateral surfaces by transcellular passage through cells or paracellular flux between cells. Tight junctions constitute the barrier to paracellular conductance; however, Little is known about the specific molecules that mediate paracell

  7. Hypermethylation of E-Cadherin and Estrogen Receptor-a Gene Promoter and Its Association with Clinicopathological Features of Breast Cancer in Iranian Patients

    Directory of Open Access Journals (Sweden)

    Mozhgan Rasti

    2009-06-01

    Full Text Available Background: Aberrant methylation of cytosine-guanine dinucleotideislands leads to inactivation of tumor suppressorgenes in breast cancer. Tumor suppressor genes are unmethylatedin normal tissue and often become hypermethylatedduring tumor formation, leading to gene silencing. We investigatedthe association between E-cadherin (CDH1 and estrogenreceptor-α (ESRα gene promoter methylation andmajor clinical and pathological features of breast cancer inIranian women.Methods: DNA was extracted from 67 primary breast tumorsand gene promoter methylation was analyzed by methylationspecificpolymerase chain reaction method.Results: Fifty percent of the samples showed aberrant methylationin at least one of the two tested loci. We detectedCDH1 hypermethylation in 41% of invasive tumors and receptor-α gene hypermethylation in 18% of invasive tumorsamples. We found no association between CDH1 and receptor-α gene hypermethylation (P=0.45. There was a correlationbetween hypermethylation of CDH1 locus and tumorsize ≥5 cm (P=0.019.Conclusion: Our data suggest that the malignant progressionof human ductal and lobular breast carcinoma in Iranianwomen involves a heterogeneous pattern of cytosine-guaninedinucleotide island hypermethylation of the CDH1 gene.

  8. p130Cas和E-cadherin在前列腺癌组织中的表达及其临床意义%Expression and clinical significance of p130Cas and E-cadherin in prostate cancer

    Institute of Scientific and Technical Information of China (English)

    胡祥坤; 程帆; 阮远; 余伟民; 张孝斌

    2011-01-01

    Objective To investigate the expression of p130Cas and E-cadherin in prostate cancer and their clinical significance.Methods The expression of p130Cas and E-cadherin in 40 cases of prostate cancer and 20 cases of benign prostatic hyperplasia (BPH) was examined by quantum-dot-based immunofluorescence histochemistry.Results The positive expression rate of p130Cas was 52.5% in prostate cancer and 15.0% in benign prostatic hyperplasia (P <0.05 ).The positive expression rate of E-cadherin was 57.5% in prostate cancer and 90.0% in benign prostatic hyperplasia ( P < 0.05 ).The expression of p130Cas and E-cadherin in prostate cancer was correlated with pathological grade and clinical stage (P <0.05 for all comparisons).Correlation was found between expression intensities of p130Cas and E-cadherin in prostate cancer (P < 0.05 ).Conclusion p130Cas and E-cadherin may be able to act as markers to the malignant degree and the prognosis of prostate cancer.%目的 探讨p130Cas和E-cadherin在前列腺癌组织中的表达及其临床意义.方法 采用量子点免疫荧光组织化学方法检测40例前列腺癌(PCa)组织和20例良性前列腺增生(BPH)组织中p130Cas和E-cadherin的表达.结果 p130Cas在BPH组织和PCa组织中表达的阳性率分别为15.0%和52.5% (P< 0.05),E-cadherin在BPH组织和PCa组织中表达的阳性率分别为90.0%和57.5% (P <0.05);PCa组织中p130Cas和E-cadherin的表达与肿瘤的病理分级和临床分期密切相关(P均<0.05);p130Cas和E-cadherin在PCa组织中的表达具有相关性(P<0.05).结论 p130Cas和E-cadherin有可能成为判断前列腺癌恶性程度及预后的参考指标.

  9. The tight junction protein ZO-2 and Janus kinase 1 mediate intercellular communications in vascular smooth muscle cells

    Energy Technology Data Exchange (ETDEWEB)

    Tkachuk, Natalia; Tkachuk, Sergey; Patecki, Margret [Department of Nephrology, Hannover Medical School, Hannover D-30625 (Germany); Kusch, Angelika [Department of Nephrology and Intensive Care Medicine, Charite Campus Virchow-Klinikum, Berlin D-13353 (Germany); Korenbaum, Elena; Haller, Hermann [Department of Nephrology, Hannover Medical School, Hannover D-30625 (Germany); Dumler, Inna, E-mail: dumler.inna@mh-hannover.de [Department of Nephrology, Hannover Medical School, Hannover D-30625 (Germany)

    2011-07-08

    Highlights: {yields} The tight junction protein ZO-2 associates with Jak1 in vascular smooth muscle cells via ZO-2 N-terminal fragment. {yields} Jak1 mediates ZO-2 tyrosine phosphorylation and ZO-2 localization to the sites of homotypic intercellular contacts. {yields} The urokinase receptor uPAR regulates ZO-2/Jak1 functional association. {yields} The ZO-2/Jak1/uPAR signaling complex is required for vascular smooth muscle cells functional network formation. -- Abstract: Recent evidence points to a multifunctional role of ZO-2, the tight junction protein of the MAGUK (membrane-associated guanylate kinase-like) family. Though ZO-2 has been found in cell types lacking tight junction structures, such as vascular smooth muscle cells (VSMC), little is known about ZO-2 function in these cells. We provide evidence that ZO-2 mediates specific homotypic cell-to-cell contacts between VSMC. Using mass spectrometry we found that ZO-2 is associated with the non-receptor tyrosine kinase Jak1. By generating specific ZO-2 constructs we further found that the N-terminal fragment of ZO-2 molecule is responsible for this interaction. Adenovirus-based expression of Jak1 inactive mutant demonstrated that Jak1 mediates ZO-2 tyrosine phosphorylation. By means of RNA silencing, expression of Jak1 mutant form and fluorescently labeled ZO-2 fusion protein we further specified that active Jak1, but not Jak1 inactive mutant, mediates ZO-2 localization to the sites of intercellular contacts. We identified the urokinase receptor uPAR as a pre-requisite for these cellular events. Functional requirement of the revealed signaling complex for VSMC network formation was confirmed in experiments using Matrigel and in contraction assay. Our findings imply involvement of the ZO-2 tight junction independent signaling complex containing Jak1 and uPAR in VSMC intercellular communications. This mechanism may contribute to vascular remodeling in occlusive cardiovascular diseases and in arteriogenesis.

  10. Cochlear implantation effect on deaf children with gap junction protein beta 2 gene mutation

    Institute of Scientific and Technical Information of China (English)

    KONG Ying; LIU Sha; WANG Su-ju; Li Shu-jing; LIANG Shuang

    2013-01-01

    Background The popularization and promotion of gene diagnosis technology makes it possible to detect deafness genes for children with congenital hearing impairment,and the proportion of gap junction protein beta 2 (GJB2) gene mutations in cochlear implant patients is 26.5% We did follow-up evaluation on auditory rehabilitation effect for all 31 deaf children with GJB2 gene mutation after cochlear implantation to provide a reference for such patients.Methods Application of “the genetic deafness gene chip detection kit” and “gene complete sequence analysis” were applied to conduct detection on common genetic deafness gene mutation hotspots of the hearing impaired children with cochlear implantation.To conduct auditory rehabilitation effect evaluation on all 31 cases of patients with GJB2 genetic deafness after 3,6 and 12 months of the operation respectively.The single factor repeated measure analysis of variance (ANOVA) was applied to analysis whether there were significant difference among the results of initial consonant of a Chinese syllable recognition at 3 different stages after the operation,the results of vowel of a Chinese syllable recognition at 3 different stages after the operation,and the results of two-syllable recognition at 3 different stages after the operation.Results The 235delC is the high-incidence mutational site in 31 cases of patients with GJB2 genetic deafness,and the total detection rate is up to 90.3% (28/31).There were significant differences in the initial consonant and the vowel of a Chinese syllable recognition rate,and the two-syllable recognition rates at 3,6,and 12 months after the operation (P<0.01).Conclusion Cochlear implantation is a safe and effective measure for auditory reconstruction,enabling patients with GJB2 hereditary severe sensorineural deafness to achieve auditory speech recognition effectively.

  11. Impact of obesity on 7,12-dimethylbenz[a]anthracene-induced altered ovarian connexin gap junction proteins in female mice

    Energy Technology Data Exchange (ETDEWEB)

    Ganesan, Shanthi, E-mail: shanthig@iastate.edu; Nteeba, Jackson, E-mail: nteeba@iastate.edu; Keating, Aileen F., E-mail: akeating@iastate.edu

    2015-01-01

    The ovarian gap junction proteins alpha 4 (GJA4 or connexin 37; CX37), alpha 1 (GJA1 or connexin 43; CX43) and gamma 1 (GJC1 or connexin 45; CX45) are involved in cell communication and folliculogenesis. 7,12-dimethylbenz[a]anthracene (DMBA) alters Cx37 and Cx43 expression in cultured neonatal rat ovaries. Additionally, obesity has an additive effect on DMBA-induced ovarian cell death and follicle depletion, thus, we investigated in vivo impacts of obesity and DMBA on CX protein levels. Ovaries were collected from lean and obese mice aged 6, 12, 18, or 24 wks. A subset of 18 wk old mice (lean and obese) were dosed with sesame oil or DMBA (1 mg/kg; ip) for 14 days and ovaries collected 3 days thereafter. Cx43 and Cx45 mRNA and protein levels decreased (P < 0.05) after 18 wks while Cx37 mRNA and protein levels decreased (P < 0.05) after 24 wks in obese ovaries. Cx37 mRNA and antral follicle protein staining intensity were reduced (P < 0.05) by obesity while total CX37 protein was reduced (P < 0.05) in DMBA exposed obese ovaries. Cx43 mRNA and total protein levels were decreased (P < 0.05) by DMBA in both lean and obese ovaries while basal protein staining intensity was reduced (P < 0.05) in obese controls. Cx45 mRNA, total protein and protein staining intensity level were decreased (P < 0.05) by obesity. These data support that obesity temporally alters gap junction protein expression and that DMBA-induced ovotoxicity may involve reduced gap junction protein function. - Highlights: • Ovarian gap junction proteins are affected by ovarian aging and obesity. • DMBA exposure negatively impacts gap junction proteins. • Altered gap junction proteins may contribute to infertility.

  12. The tight junction protein JAM-A functions as coreceptor for rotavirus entry into MA104 cells.

    Science.gov (United States)

    Torres-Flores, Jesús M; Silva-Ayala, Daniela; Espinoza, Marco A; López, Susana; Arias, Carlos F

    2015-01-15

    Several molecules have been identified as receptors or coreceptors for rotavirus infection, including glycans, integrins, and hsc70. In this work we report that the tight junction proteins JAM-A, occludin, and ZO-1 play an important role during rotavirus entry into MA104 cells. JAM-A was found to function as coreceptor for rotavirus strains RRV, Wa, and UK, but not for rotavirus YM. Reassortant viruses derived from rotaviruses RRV and YM showed that the virus spike protein VP4 determines the use of JAM-A as coreceptor.

  13. Snail、E-cadherin和MMP-2在I型子宫内膜癌中的表达及临床意义%Expression of Snail, E-cadherin and MMP-2 in type I endometrial carcinoma and its clinicopathological significance

    Institute of Scientific and Technical Information of China (English)

    潘洪琳; 冯振中

    2013-01-01

    Objective To investigate the expression of Snail, E-cadherin and matrix metal oproteinase-2 (MMP-2) in pa-tients with type I endometrial carcinoma and its clinicopathological significance. Methods Tissue microarray and immunohisto-chemical staining were performed to evaluate Snail, E-cadherin, and MMP-2 expression in 58 cases of endometrial carcinoma, 17 cases of atypical hyperplasia and 21normal endometrial samples. The correlation between these three markers with clinico-pathological features were examined. Results The expression of Snail, E-cadherin and MMP-2 proteins was significantly changed as lesions progressed from normal endometrium through atypical hyperplasia to carcinoma, (P<0.01). In addition, in-creased expression of Snail was tightly associated with FIGO stage and lymph node metastasis. Down-regulated expression of E-cadherin protein showed a significantly correlation with myometrial invasion and lymph node metastasis (P<0.05). Similarly, MMP-2 protein also correlated with lymph node metastasis(P<0.05). In primary endometrioid adenocarcinoma, there was a sig-nificant negative association of Snail with E-cadherin expression(r=-0.259, P=0.049), while the expression of Snail was positively correlated with MMP-2 (r=0.447, P<0.01). Conclusion Snail and MMP-2 expression is up-regulated and E-cadherin expres-sion down-regulated in endometrial carcinoma, and detection of these three markers may predict the potential malignancy and tumor behavior.%  目的探讨子宫内膜样腺癌组织中转录因子Snail、上皮钙黏附素(E-cadherin)和基质金属蛋白酶2(MMP-2)的表达关系,研究Snail促进子宫内膜癌侵袭转移的机制及临床意义。方法采用免疫组化方法,结合组织芯片技术,检测58例I型子宫内膜癌、17例内膜不典型增生、21例正常内膜组织中Snail、E-cadherin和MMP-2的表达水平,分析3种蛋白表达之间的相关性及与临床病理因素的关系。结果Ⅰ型子宫

  14. Glucocorticoids upregulates transepithelial electrical resistance and expression of tight junction-related protein in human trabecular meshwork cells

    Institute of Scientific and Technical Information of China (English)

    ZHUO Ye-hong; HUANG Ya-lin; WEI Yan-tao; LING Yun-lan; LIN Ming-kai; GE Jian

    2005-01-01

    @@ The trabecular meshwork is located at the anterior chamber angle, and is the main route for the outflow of aqueous humor. It is composed of perforated sheets of collagen and elastic tissue covered by trabecular meshwork (TM) cells, forming a filter with decreasing pore size as the canal of Schlemm is approached. TM cells have some endothelial properties, such as the presence of intercellular junctional complexes, particularly tight junctions (TJs). TJs form paracellular seals between adjacent cells and act as fences that segregate protein (and partially lipid) components of the apical and basolateral plasma membrane domains. Under the electron microscope, TJs appear as a series of discrete contacts between the lateral membranes of adjacent cells.

  15. Enhanced Protein Production in Escherichia coli by Optimization of Cloning Scars at the Vector-Coding Sequence Junction

    DEFF Research Database (Denmark)

    Mirzadeh, Kiavash; Martinez, Virginia; Toddo, Stephen

    2015-01-01

    Protein production in Escherichia coli is a fundamental activity for a large fraction of academic, pharmaceutical, and industrial research laboratories. Maximum production is usually sought, as this reduces costs and facilitates downstream purification steps. Frustratingly, many coding sequences...... are poorly expressed even when they are codon-optimized and expressed from vectors with powerful genetic elements. In this study, we show that poor expression can be caused by certain nucleotide sequences (e.g., cloning scars) at the junction between the vector and the coding sequence. Since these sequences...... lie between the Shine-Dalgarno sequence and the start codon, they are an integral part of the translation initiation region. To identify the most optimal sequences, we devised a simple and inexpensive PCR-based step that generates sequence variants at the vector-coding sequence junction...

  16. Expression and significance of E-cadherin in adenoid cystic carcinoma of salivary glands%涎腺腺样囊性癌组织中E-钙黏蛋白的表达及临床意义

    Institute of Scientific and Technical Information of China (English)

    葛明华; 凌志强; 谭卓; 陈超; 徐加杰; 余江流

    2012-01-01

    Objective To examine the expression of E-cadherin and the methylation status of CDH1 and explore their clinical significance in salivary adenoid cystic carcinoma (SACC).Methods The expression of E-cadherin was detected by the immunohistochemical method.And the methylation of CDH1 gene promoter 5'-CpG island was analyzed by real-time methylation-specific polymerase chain reaction ( realtime MSP) in salivary adenoid cystic carcinoma and normal salivary gland tissue respectively.Results The expression rate of E-cadherin was lower in SACC than that in normal salivary gland tissue ( 100.0% vs 55.6%,P < 0.05).And the expression of E-cadherin was associated with different histopathological types,T-stage,nerve invasion,lymphatic and distant metastasis (P < 0.05).However,there was no correlation between the expression of E-cadherin and gender,age and tumor location.Partial methylation of CDH1 was detected in 3 of 30 cases with a positive expression of E-cadherin and full methylation of CDH1 in 23 of 24 cases with a negative expression of E-cadherin.There was a negative correlation between the expression of Ecadherin and the methylation of CDH1 in salivary adenoid cystic carcinoma ( r =- 0.483,P < 0.001 ).Conclusion The down-regulation of E-cadherin,as modulated by the methylation of CDH1,may contribute to nerve invasion,lymphatic and distant metastasis in SACC.Thus it may be used as a biological indicator of malignancy and prognosis.%目的 研究E-钙黏蛋白在涎腺腺样囊性癌(SACC)中表达水平、CDH1甲基化状态及临床意义.方法 用免疫组化的方法检测E-钙黏蛋白在SACC及正常涎腺组织中的表达,并用实时荧光甲基化特异性PCR分析CDH1甲基化状态.结果 与正常涎腺组织相比,E-钙黏蛋白在SACC表达低,差异有统计学意义(100.0%比55.6%,P<0.05),E-钙黏蛋白表达与组织病理学类型、T-分期、神经侵犯、淋巴结转移及远处转移相关(P<0.05);而与性别、年龄

  17. Expression and clinical significance of GS,E-cadherin and β-catenin in hepatocellular carcinoma%GS、E-cadherin和β-catenin在肝细胞癌中的表达及其临床意义

    Institute of Scientific and Technical Information of China (English)

    周新木; 陈丽荣

    2013-01-01

    目的 探讨谷氨酰胺合成酶(glutamine synthetase GS)、E-钙粘蛋白(E-cadherin)和β-连环蛋白(β-catenin)在肝细胞癌中的表达及其与临床病理特征和预后的关系.方法 采用免疫组织化学Envision法检测182例肝细胞癌和92例癌旁肝组织中GS、E-cadherin和β-catenin的表达情况,并分析其与临床病理特征和预后的关系.结果 GS在肝细胞癌阳性表达率为77.5%,明显高于癌旁肝组织(4.3%),差异显著(P<0.05);肝细胞癌E-cadherin和β-catenin异常表达率分别为59.3%和58.8%,亦高于癌旁肝组织(30.4%和26.1%),差异显著(P<0.05).肝细胞癌中GS的表达与TNM分期、转移和术后复发显著相关(P<0.05);E-cadherin和β-catenin异常表达与脉管内瘤栓、TNM分期、转移和术后复发显著相关(P<0.05).肝细胞癌中GS表达与E-cadherin、β-catenin异常表达正相关.结论 肝细胞癌中GS的高表达,与E-cadherin和β-catenin表达的下调,可能是肝细胞癌侵袭和转移的重要机制之一,联合检测GS、E-cadherin和β-catenin可能有助于判断肝细胞癌的恶性程度、转移潜能及预后分析.%Objective To investigate the expression of glutamine synthetase(GS), E-cadherin and β-catenin in hepatocellular carcinoma and its relation to clinicopathological characterisitics and prognosis. Methods With the method of immunohistochemical Envision, the expressions of GS, E-cadherin and β-catenin were examined in 182 cases of hepatocellular carcinoma and 92 cases of adjacent non-neoplastic liver tissue. We then analyzed their relations to the clinicopathological data of hepatocellular carcinoma. Results In the hepatocellular carcinoma group,77. 5% samples expressed GS, significantly higher than in surrounding liver tissue (4. 3% P<0. 05). The expression of GS was positively correlated with TNM stage, tumor metastasis and recur-rence(P<0. 05). In hepatocellular carcinoma, aberrant expression of E-cadherin and β-catenin was

  18. DDX3 loss by p53 inactivation promotes tumor malignancy via the MDM2/Slug/E-cadherin pathway and poor patient outcome in non-small-cell lung cancer.

    Science.gov (United States)

    Wu, D-W; Lee, M-C; Wang, J; Chen, C-Y; Cheng, Y-W; Lee, H

    2014-03-20

    P53 inactivation by p53 mutation and E6 oncoprotein has a crucial role in human carcinogenesis. DDX3 has been shown to be a target of p53. In this study, we hypothesized that DDX3 loss by p53 inactivation may promote tumor malignancy and poor patients' outcome. Mechanically, DDX3 loss by p53 knockdown and E6 overexpression was observed in A549 lung cancer cells. Conversely, DDX3 expression was markedly elevated by wild-type (WT) p53 ectopic expression in p53-null H1299 cells, E6-knockdown TL-1 lung cancer and SiHa cervical cancer cells. Interestingly, DDX3 loss promotes soft-agar growth and invasive capability; however, both capabilities were suppressed by DDX3 overexpression. We next expected that DDX3 loss might result in Slug-suppressed E-cadherin expression via decreased MDM2-mediated Slug degradation. As expected, MDM2 transcription is suppressed by DDX3 loss via decreased SP1 binding activity to the MDM2 promoter. Consequently, Slug expression was elevated by the reduction of MDM2 because of DDX3 loss, and E-cadherin expression was suppressed by Slug. Consistent observations in the correlation of DDX3 loss with MDM2, Slug and E-cadherin were seen in lung tumors from lung cancer patients. In addition, patients with low-DDX3 tumors had poorer survival and relapse than patients with high-DDX3 tumors. In conclusion, we suggest that DDX3 loss by p53 inactivation via MDM2/Slug/E-cadherin pathway promotes tumor malignancy and poor patient outcome.

  19. DN-R175H p53 mutation is more effective than p53 interference in inducing epithelial disorganization and activation of proliferation signals in human carcinoma cells: role of E-cadherin.

    Science.gov (United States)

    Rieber, Manuel; Strasberg Rieber, Mary

    2009-10-01

    One of the hallmarks of carcinomas is epithelial disorganization, linked to overexpression of matrix metalloproteases (MMP) like MMP-9, loss of intercellular E-cadherin and activation of epidermal growth receptor (EGFR/erbB1). Since the p53 tumor suppressor pathway is inactivated in most human cancers due to gene mutations or defective wt p53 signaling, we now investigated in human wt p53 breast carcinoma MCF-7 cells, whether single treatment with the p53 transactivation pharmacological inhibitor pifithrin-alpha, transient p53 siRNA interference or stable insertion of a dominant-negative (DN) R175H p53 mutant increase: (i) EGFR/erbB1 activation, (ii) MMP-9 expression and (iii) loss of surface E-cadherin. Transient abrogation of wt p53 function increased phosphorylation of EGFR/erbB1 and MMP-9 expression. However, all these effects were much more pronounced in cells stably transduced with the dominant negative-Arg-175His mutant p53 (DN-R175H mutant p53), which also showed loss of epithelial cytoarchitecture and extensive E-cadherin downregulation. Collectively, these results support the notion that the DN-R175H mutant p53 exerts a gain of oncogenic function by promoting disruption of E-cadherin intercellular contacts and activation of proliferation signals. Our data suggests that epithelial shape and growth control are unequally affected depending on how wt p53 function is impaired and whether partial or full tumor suppressor activity is lost.

  20. Expression of TM4SF10, a Claudin/EMP/PMP22 family cell junction protein, during mouse kidney development and podocyte differentiation.

    Science.gov (United States)

    Bruggeman, Leslie A; Martinka, Scott; Simske, Jeffrey S

    2007-02-01

    Cell junctions in the nephron are highly specialized to perform specific and distinct filtration and reabsorption functions. The mature kidney forms complex cell junctions including slit diaphragms that prevent the passage of serum proteins into the filtrate, and tubule cell junctions that regulate specific paracellular ion reuptake. We have investigated the expression of TM4SF10 (Trans-Membrane tetra(4)-Span Family 10) in mouse kidneys. TM4SF10 is the vertebrate orthologue of Caenorhabditis elegans VAB-9, a tetraspan adherens junction protein in the PMP22/EMP/Claudin family of proteins. We found that TM4SF10 localizes at the basal-most region of podocyte precursors before the capillary loop stage, at some tubule precursors, and at the ureteric bud junction with S-shaped bodies. Overall expression of TM4SF10 peaked at postnatal day 4 and was virtually absent in adult kidneys. The very limited expression of TM4SF10 protein that persisted into adulthood was restricted to a few tubule segments but remained localized to the basal region of lateral membranes. In undifferentiated cultured podocytes, TM4SF10 localized to the perinuclear region and translocated to the cell membrane after Cadherin appearance at cell-cell contacts. TM4SF10 colocalized with ZO1 and p120ctn in undifferentiated confluent podocytes and also colocalized with the tips of actin filaments at cell contacts. Upon differentiation of cultured podocytes, TM4SF10 protein disappeared from cell contacts and expression ceased. These results suggest that TM4SF10 functions during differentiation of podocytes and may participate in the maturation of cell junctions from simple adherens junctions to elaborate slit diaphragms. TM4SF10 may define a new class of Claudin-like proteins that function during junctional development.

  1. The Role of Aquaporin and Tight Junction Proteins in the Regulation of Water Movement in Larval Zebrafish (Danio rerio)

    Science.gov (United States)

    Kwong, Raymond W. M.; Kumai, Yusuke; Perry, Steve F.

    2013-01-01

    Teleost fish living in freshwater are challenged by passive water influx; however the molecular mechanisms regulating water influx in fish are not well understood. The potential involvement of aquaporins (AQP) and epithelial tight junction proteins in the regulation of transcellular and paracellular water movement was investigated in larval zebrafish (Danio rerio). We observed that the half-time for saturation of water influx (Ku) was 4.3±0.9 min, and reached equilibrium at approximately 30 min. These findings suggest a high turnover rate of water between the fish and the environment. Water influx was reduced by the putative AQP inhibitor phloretin (100 or 500 μM). Immunohistochemistry and confocal microscopy revealed that AQP1a1 protein was expressed in cells on the yolk sac epithelium. A substantial number of these AQP1a1-positive cells were identified as ionocytes, either H+-ATPase-rich cells or Na+/K+-ATPase-rich cells. AQP1a1 appeared to be expressed predominantly on the basolateral membranes of ionocytes, suggesting its potential involvement in regulating ionocyte volume and/or water flux into the circulation. Additionally, translational gene knockdown of AQP1a1 protein reduced water influx by approximately 30%, further indicating a role for AQP1a1 in facilitating transcellular water uptake. On the other hand, incubation with the Ca2+-chelator EDTA or knockdown of the epithelial tight junction protein claudin-b significantly increased water influx. These findings indicate that the epithelial tight junctions normally act to restrict paracellular water influx. Together, the results of the present study provide direct in vivo evidence that water movement can occur through transcellular routes (via AQP); the paracellular routes may become significant when the paracellular permeability is increased. PMID:23967101

  2. The role of aquaporin and tight junction proteins in the regulation of water movement in larval zebrafish (Danio rerio.

    Directory of Open Access Journals (Sweden)

    Raymond W M Kwong

    Full Text Available Teleost fish living in freshwater are challenged by passive water influx; however the molecular mechanisms regulating water influx in fish are not well understood. The potential involvement of aquaporins (AQP and epithelial tight junction proteins in the regulation of transcellular and paracellular water movement was investigated in larval zebrafish (Danio rerio. We observed that the half-time for saturation of water influx (K(u was 4.3±0.9 min, and reached equilibrium at approximately 30 min. These findings suggest a high turnover rate of water between the fish and the environment. Water influx was reduced by the putative AQP inhibitor phloretin (100 or 500 μM. Immunohistochemistry and confocal microscopy revealed that AQP1a1 protein was expressed in cells on the yolk sac epithelium. A substantial number of these AQP1a1-positive cells were identified as ionocytes, either H⁺-ATPase-rich cells or Na⁺/K⁺-ATPase-rich cells. AQP1a1 appeared to be expressed predominantly on the basolateral membranes of ionocytes, suggesting its potential involvement in regulating ionocyte volume and/or water flux into the circulation. Additionally, translational gene knockdown of AQP1a1 protein reduced water influx by approximately 30%, further indicating a role for AQP1a1 in facilitating transcellular water uptake. On the other hand, incubation with the Ca²⁺-chelator EDTA or knockdown of the epithelial tight junction protein claudin-b significantly increased water influx. These findings indicate that the epithelial tight junctions normally act to restrict paracellular water influx. Together, the results of the present study provide direct in vivo evidence that water movement can occur through transcellular routes (via AQP; the paracellular routes may become significant when the paracellular permeability is increased.

  3. miR-200c affects the mRNA expression of E-cadherin by regulating the mRNA level of TCF8 during post-natal epididymal development in juvenile rats

    Institute of Scientific and Technical Information of China (English)

    Junfeng Wang; Kangcheng Ruan

    2010-01-01

    The unique temporal expression pattern of miR-200c in epididymis during post-natal development in juvenile rats was revealed by our home-made miRNA microarray in this paper.It was found that miR-200c expressed in the lowest level at Day 7 and then increased to the highest at Day 36 followed by a dramatic decrease.The pattern was exactly inverse to that of mRNA expression of transcrip tion factor 8(TCF8)revealed by quantitative real-time polymerase chain reaction(qRT-PCR),providing an extra evidence that TCF8 is one degradation target of miR-200c even in epididymis.Moreover,the qRT-PCR study on expression of E-cadherin and interleukin-2 indicated that miR-200c does exert an obvious effect on the mRNA expression of E-cadherin by directly regulating the mRNA level of TCF8,although the effect on interleukin-2 is not obvious as on E-cadherin,which implicates that interleukin-2 may be also regulated by other factors besides TCF8 in rat epididymis.

  4. Expression of E-cadherin and N-cadherin in perinatal hamster ovary: possible involvement in primordial follicle formation and regulation by follicle-stimulating hormone.

    Science.gov (United States)

    Wang, Cheng; Roy, Shyamal K

    2010-05-01

    We examined the expression and hormonal regulation of E-cadherin (CDH1) and N-cadherin (CDH2) with respect to primordial follicle formation. Hamster Cdh1 and Cdh2 cDNA and amino acid sequences were more than 90% similar to those of the mouse, rat, and human. Although CDH1 expression remained exclusively in the oocytes during neonatal ovary development, CDH2 expression shifted from the oocytes to granulosa cells of primordial follicles on postnatal day (P)8. Subsequently, strong CDH2 expression was restricted to granulosa cells of growing follicles. Cdh2 mRNA levels in the ovary decreased from embryonic d 13 through P10 with a transient increase on P7, which was the day before the appearance of primordial follicles. Cdh1 mRNA levels decreased from embryonic d 13 through P3 and then showed a transient increase on P8, coinciding with the formation of primordial follicles. CDH1 and CDH2 expression were consistent with that of mRNA. Neutralization of FSH in utero impaired primordial follicle formation with an associated decrease in Cdh2 mRNA and CDH2, but an increase in Cdh1 mRNA and CDH1 expression. The altered expression was reversed by equine chorionic gonadotropin treatment on P1. Whereas a CDH2 antibody significantly reduced the formation of primordial and primary follicles in vitro, a CDH1 antibody had the opposite effect. This is the first evidence to suggest that primordial follicle formation requires a differential spatiotemporal expression and action of CDH1 and CDH2. Further, FSH regulation of primordial follicle formation may involve the action of CDH1 and CDH2.

  5. Quantum dot-based quantification revealed differences in subcellular localization of EGFR and E-cadherin between EGFR-TKI sensitive and insensitive cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Huang Donghai; Su Ling; Peng Xianghong; Zhang Hongzheng; Khuri, Fadlo R; Shin, Dong M; Chen Zhuo [Department of Hematology and Medical Oncology, Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA (United States)], E-mail: gzchen@emory.edu

    2009-06-03

    Nanoparticle quantum dots (QDs) provide sharper and more photostable fluorescent signals than organic dyes, allowing quantification of multiple biomarkers simultaneously. In this study, we quantified the expression of epidermal growth factor receptor (EGFR) and E-cadherin (E-cad) in the same cells simultaneously by using secondary antibody-conjugated QDs with two different emission wavelengths (QD605 and QD565) and compared the cellular distribution of EGFR and E-cad between EGFR-tyrosine kinase inhibitor (TKI)-insensitive and -sensitive lung and head and neck cancer cell lines. Relocalization of EGFR and E-cad upon treatment with the EGFR-TKI erlotinib in the presence of EGF was visualized and analyzed quantitatively. Our results showed that QD-immunocytochemistry (ICC)-based technology can not only quantify basal levels of multiple biomarkers but also track the localization of the biomarkers upon biostimulation. With this new technology we found that in EGFR-TKI-insensitive cells, EGFR and E-cad were located mainly in the cytoplasm; while in sensitive cells, they were found mainly on the cell membrane. After induction with EGF, both EGFR and E-cad internalized to the cytoplasm, but the internalization capability in sensitive cells was greater than that in insensitive cells. Quantification also showed that inhibition of EGF-induced EGFR and E-cad internalization by erlotinib in the sensitive cells was stronger than that in the insensitive cells. These studies demonstrate substantial differences between EGFR-TKI-insensitive and -sensitive cancer cells in EGFR and E-cad expression and localization both at the basal level and in response to EGF and erlotinib. QD-based analysis facilitates the understanding of the features of EGFR-TKI-insensitive versus -sensitive cancer cells and may be used in the prediction of patient response to EGFR-targeted therapy.

  6. Autophagy and tight junction proteins in the intestine and intestinal diseases

    Directory of Open Access Journals (Sweden)

    Chien-An A. Hu

    2015-09-01

    Full Text Available The intestinal epithelium (IE forms an indispensible barrier and interface between the intestinal interstitium and the luminal environment. The IE regulates water, ion and nutrient transport while providing a barrier against toxins, pathogens (bacteria, fungi and virus and antigens. The apical intercellular tight junctions (TJ are responsible for the paracellular barrier function and regulate trans-epithelial flux of ions and solutes between adjacent cells. Increased intestinal permeability caused by defects in the IE TJ barrier is considered an important pathogenic factor for the development of intestinal inflammation, diarrhea and malnutrition in humans and animals. In fact, defects in the IE TJ barrier allow increased antigenic penetration, resulting in an amplified inflammatory response in inflammatory bowel disease (IBD, necrotizing enterocolitis and ischemia-reperfusion injury. Conversely, the beneficial enhancement of the intestinal TJ barrier has been shown to resolve intestinal inflammation and apoptosis in both animal models of IBD and human IBD. Autophagy (self-eating mechanism is an intracellular lysosome-dependent degradation and recycling pathway essential for cell survival and homeostasis. Dysregulated autophagy has been shown to be directly associated with many pathological processes, including IBD. Importantly, the crosstalk between IE TJ and autophagy has been revealed recently. We showed that autophagy enhanced IE TJ barrier function by increasing transepithelial resistance and reducing the paracellular permeability of small solutes and ions, which is, in part, by targeting claudin-2, a cation-selective, pore-forming, transmembrane TJ protein, for lysosome (autophagy-mediated degradation. Interestingly, previous studies have shown that the inflamed intestinal mucosa in patients with active IBD has increased claudin-2 expression. In addition, inflammatory cytokines (for example, tumor necrosis factor-α, interleukin-6

  7. Involvement of YAP, TAZ and HSP90 in contact guidance and intercellular junction formation in corneal epithelial cells.

    Directory of Open Access Journals (Sweden)

    Vijay Krishna Raghunathan

    Full Text Available The extracellular environment possesses a rich milieu of biophysical and biochemical signaling cues that are simultaneously integrated by cells and influence cellular phenotype. Yes-associated protein (YAP and transcriptional co-activator with PDZ-binding motif (WWTR1; TAZ, two important signaling molecules of the Hippo pathway, have been recently implicated as nuclear relays of cytoskeletal changes mediated by substratum rigidity and topography. These proteins intersect with other important intracellular signaling pathways (e.g. Wnt and TGFβ. In the cornea, epithelial cells adhere to the stroma through a 3-dimensional topography-rich basement membrane, with features in the nano-submicron size-scale that are capable of profoundly modulating a wide range of fundamental cell behaviors. The influences of substratum-topography, YAP/TAZ knockdown, and HSP90 inhibition on cell morphology, YAP/TAZ localization, and the expression of TGFβ2 and CTGF, were investigated. The results demonstrate (a that knockdown of TAZ enhances contact guidance in a YAP dependent manner, (b that CTGF is predominantly regulated by YAP and not TAZ, and (c that TGFβ2 is regulated by both YAP and TAZ in these cells. Additionally, inhibition of HSP90 resulted in nuclear localization and subsequent transcriptional-activation of YAP, formation of cell-cell junctions and co-localization of E-cadherin and β-catenin at adherens junctions. Results presented in this study reflect the complexities underlying the molecular relationships between the cytoskeleton, growth factors, heat shock proteins, and co-activators of transcription that impact mechanotransduction. The data reveal the importance of YAP/TAZ on the cell behaviors, and gene and protein expression.

  8. Human articular chondrocytes express multiple gap junction proteins: differential expression of connexins in normal and osteoarthritic cartilage.

    Science.gov (United States)

    Mayan, Maria D; Carpintero-Fernandez, Paula; Gago-Fuentes, Raquel; Martinez-de-Ilarduya, Oskar; Wang, Hong-Zhang; Valiunas, Virginijus; Brink, Peter; Blanco, Francisco J

    2013-04-01

    Osteoarthritis (OA) is the most common joint disease and involves progressive degeneration of articular cartilage. The aim of this study was to investigate if chondrocytes from human articular cartilage express gap junction proteins called connexins (Cxs). We show that human chondrocytes in tissue express Cx43, Cx45, Cx32, and Cx46. We also find that primary chondrocytes from adults retain the capacity to form functional voltage-dependent gap junctions. Immunohistochemistry experiments in cartilage from OA patients revealed significantly elevated levels of Cx43 and Cx45 in the superficial zone and down through the next approximately 1000 μm of tissue. These zones corresponded with regions damaged in OA that also had high levels of proliferative cell nuclear antigen. An increased number of Cxs may help explain the increased proliferation of cells in clusters that finally lead to tissue homeostasis loss. Conversely, high levels of Cxs in OA cartilage reflect the increased number of adjacent cells in clusters that are able to interact directly by gap junctions as compared with hemichannels on single cells in normal cartilage. Our data provide strong evidence that OA patients have a loss of the usual ordered distribution of Cxs in the damaged zones and that the reductions in Cx43 levels are accompanied by the loss of correct Cx localization in the nondamaged areas. Copyright © 2013 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  9. Protein kinase C-dependent regulation of connexin43 gap junctions and hemichannels

    DEFF Research Database (Denmark)

    Alstrøm, Jette Skov; Stroemlund, Line Waring; Nielsen, Morten Schak

    2015-01-01

    and allow transport of molecules such as fluorescent dyes and ATP. A range of phosphorylated amino acids have been detected in the C-terminus of Cx43 and their physiological role has been intensively studied both in the gap junctional form of Cx43 and in its hemichannel configuration. We present the current...

  10. Butyrate Enhances the Intestinal Barrier by Facilitating Tight Junction Assembly via Activation of AMP-Activated Protein Kinase in Caco-2 Cell Monolayers12

    Science.gov (United States)

    Peng, Luying; Li, Zhong-Rong; Green, Robert S.; Holzman, Ian R.; Lin, Jing

    2009-01-01

    Butyrate, one of the SCFA, promotes the development of the intestinal barrier. However, the molecular mechanisms underlying the butyrate regulation of the intestinal barrier are unknown. To test the hypothesis that the effect of butyrate on the intestinal barrier is mediated by the regulation of the assembly of tight junctions involving the activation of the AMP-activated protein kinase (AMPK), we determined the effect of butyrate on the intestinal barrier by measuring the transepithelial electrical resistance (TER) and inulin permeability in a Caco-2 cell monolayer model. We further used a calcium switch assay to study the assembly of epithelial tight junctions and determined the effect of butyrate on the assembly of epithelial tight junctions and AMPK activity. We demonstrated that the butyrate treatment increased AMPK activity and accelerated the assembly of tight junctions as shown by the reorganization of tight junction proteins, as well as the development of TER. AMPK activity was also upregulated by butyrate during calcium switch-induced tight junction assembly. Compound C, a specific AMPK inhibitor, inhibited the butyrate-induced activation of AMPK. The facilitating effect of butyrate on the increases in TER in standard culture media, as well as after calcium switch, was abolished by compound C. We conclude that butyrate enhances the intestinal barrier by regulating the assembly of tight junctions. This dynamic process is mediated by the activation of AMPK. These results suggest an intriguing link between SCFA and the intracellular energy sensor for the development of the intestinal barrier. PMID:19625695

  11. Butyrate enhances the intestinal barrier by facilitating tight junction assembly via activation of AMP-activated protein kinase in Caco-2 cell monolayers.

    Science.gov (United States)

    Peng, Luying; Li, Zhong-Rong; Green, Robert S; Holzman, Ian R; Lin, Jing

    2009-09-01

    Butyrate, one of the SCFA, promotes the development of the intestinal barrier. However, the molecular mechanisms underlying the butyrate regulation of the intestinal barrier are unknown. To test the hypothesis that the effect of butyrate on the intestinal barrier is mediated by the regulation of the assembly of tight junctions involving the activation of the AMP-activated protein kinase (AMPK), we determined the effect of butyrate on the intestinal barrier by measuring the transepithelial electrical resistance (TER) and inulin permeability in a Caco-2 cell monolayer model. We further used a calcium switch assay to study the assembly of epithelial tight junctions and determined the effect of butyrate on the assembly of epithelial tight junctions and AMPK activity. We demonstrated that the butyrate treatment increased AMPK activity and accelerated the assembly of tight junctions as shown by the reorganization of tight junction proteins, as well as the development of TER. AMPK activity was also upregulated by butyrate during calcium switch-induced tight junction assembly. Compound C, a specific AMPK inhibitor, inhibited the butyrate-induced activation of AMPK. The facilitating effect of butyrate on the increases in TER in standard culture media, as well as after calcium switch, was abolished by compound C. We conclude that butyrate enhances the intestinal barrier by regulating the assembly of tight junctions. This dynamic process is mediated by the activation of AMPK. These results suggest an intriguing link between SCFA and the intracellular energy sensor for the development of the intestinal barrier.

  12. [6]-Gingerol Prevents Disassembly of Cell Junctions and Activities of MMPs in Invasive Human Pancreas Cancer Cells through ERK/NF-κB/Snail Signal Transduction Pathway

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    Sung Ok Kim

    2013-01-01

    Full Text Available To study the effects of [6]-gingerol, a ginger phytochemical, on tight junction (TJ molecules, we investigated TJ tightening and signal transduction pathways in human pancreatic duct cell-derived cancer cell line PANC-1. The following methods were utilized: MTT assay to determine cytotoxicity; zymography to examine matrix metalloproteinase (MMP activities; transepithelial electrical resistance (TER and paracellular flux for TJ measurement; RT-PCR and immunoblotting for proteins related to TJ and invasion; and EMSA for NF-κB activity in PANC-1 cells. Results revealed that TER significantly increased and claudin 4 and MMP-9 decreased compared to those of the control. TJ protein levels, including zonula occludens (ZO- 1, occludin, and E-cadherin, increased in [6]-gingerol-treated cells, which correlated with a decrease in paracellular flux and MMP activity. Furthermore, NF-κB/Snail nuclear translocation was suppressed via downregulation of the extracellular signal-regulated kinase (ERK pathway in response to [6]-gingerol treatment. Moreover, treatment with U0126, an ERK inhibitor, completely blocked NF-κB activity. In conclusion, these findings demonstrate that [6]-gingerol regulates TJ-related proteins and suppresses invasion and metastasis through NF-κB/Snail inhibition via inhibition of the ERK pathway. Therefore, [6]-gingerol may suppress the invasive activity of PANC-1 cells.

  13. Basolateral junction proteins regulate competition for the follicle stem cell niche in the Drosophila ovary.

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    Kronen, Maria R; Schoenfelder, Kevin P; Klein, Allon M; Nystul, Todd G

    2014-01-01

    Epithelial stem cells are routinely lost or damaged during adult life and must therefore be replaced to maintain homeostasis. Recent studies indicate that stem cell replacement occurs through neutral competition in many types of epithelial tissues, but little is known about the factors that determine competitive outcome. The epithelial follicle stem cells (FSCs) in the Drosophila ovary are regularly lost and replaced during normal homeostasis, and we show that FSC replacement conforms to a model of neutral competition. In addition, we found that FSCs mutant for the basolateral junction genes, lethal giant larvae (lgl) or discs large (dlg), undergo a biased competition for niche occupancy characterized by increased invasion of neighboring FSCs and reduced loss. Interestingly, FSCs mutant for a third basolateral junction gene, scribble (scrib), do not exhibit biased competition, suggesting that Lgl and Dlg regulate niche competition through a Scrib-independent process. Lastly, we found that FSCs have a unique cell polarity characterized by broadly distributed adherens junctions and the lack of a mature apical domain. Collectively, these observations indicate that Lgl and Dlg promote the differentiation of FSC progeny to a state in which they are less prone to invade the neighboring niche. In addition, we demonstrate that the neutral drift model can be adapted to quantify non-neutral behavior of mutant clones.

  14. Basolateral junction proteins regulate competition for the follicle stem cell niche in the Drosophila ovary.

    Directory of Open Access Journals (Sweden)

    Maria R Kronen

    Full Text Available Epithelial stem cells are routinely lost or damaged during adult life and must therefore be replaced to maintain homeostasis. Recent studies indicate that stem cell replacement occurs through neutral competition in many types of epithelial tissues, but little is known about the factors that determine competitive outcome. The epithelial follicle stem cells (FSCs in the Drosophila ovary are regularly lost and replaced during normal homeostasis, and we show that FSC replacement conforms to a model of neutral competition. In addition, we found that FSCs mutant for the basolateral junction genes, lethal giant larvae (lgl or discs large (dlg, undergo a biased competition for niche occupancy characterized by increased invasion of neighboring FSCs and reduced loss. Interestingly, FSCs mutant for a third basolateral junction gene, scribble (scrib, do not exhibit biased competition, suggesting that Lgl and Dlg regulate niche competition through a Scrib-independent process. Lastly, we found that FSCs have a unique cell polarity characterized by broadly distributed adherens junctions and the lack of a mature apical domain. Collectively, these observations indicate that Lgl and Dlg promote the differentiation of FSC progeny to a state in which they are less prone to invade the neighboring niche. In addition, we demonstrate that the neutral drift model can be adapted to quantify non-neutral behavior of mutant clones.

  15. Possible role of HIWI2 in modulating tight junction proteins in retinal pigment epithelial cells through Akt signaling pathway.

    Science.gov (United States)

    Sivagurunathan, Suganya; Palanisamy, Karthikka; Arunachalam, Jayamuruga Pandian; Chidambaram, Subbulakshmi

    2017-03-01

    PIWI subfamily of proteins is shown to be primarily expressed in germline cells. They maintain the genomic integrity by silencing the transposable elements. Although the role of PIWI proteins in germ cells has been documented, their presence and function in somatic cells remains unclear. Intriguingly, we detected all four members of PIWI-like proteins in human ocular tissues and somatic cell lines. When HIWI2 was knocked down in retinal pigment epithelial cells, the typical honeycomb morphology was affected. Further analysis showed that the expression of tight junction (TJ) proteins, CLDN1, and TJP1 were altered in HIWI2 knockdown. Moreover, confocal imaging revealed disrupted TJP1 assembly at the TJ. Previous studies report the role of GSK3β in regulating TJ proteins. Accordingly, phospho-kinase proteome profiler array indicated increased phosphorylation of Akt and GSK3α/β in HIWI2 knockdown, suggesting that HIWI2 might affect TJ proteins through Akt-GSK3α/β signaling axis. Moreover, treating the HIWI2 knockdown cells with wortmannin increased the levels of TJP1 and CLDN1. Taken together, our study demonstrates the presence of PIWI-like proteins in somatic cells and the possible role of HIWI2 in preserving the functional integrity of epithelial cells probably by modulating the phosphorylation status of Akt.

  16. Dipyridamole increases gap junction coupling in bovine GM-7373 aortic endothelial cells by a cAMP-protein kinase A dependent pathway.

    Science.gov (United States)

    Begandt, D; Bintig, W; Oberheide, K; Schlie, S; Ngezahayo, A

    2010-02-01

    The scrape-loading/dye transfer technique was applied on the bovine aortic endothelial cell line GM-7373 to analyze the effects of the antithrombolytic drug dipyridamole on gap junction coupling in endothelial cells. We found that a cell treatment for 24 h with dipyridamole in therapeutically relevant concentrations (1-100 microM) increased gap junction coupling in a dose dependent manner. Similar to dipyridamole, forskolin as well as 8-Br-cAMP increased the gap junction coupling, while dibutyryl-cGMP (db-cGMP) did not affect the gap junction coupling of the GM-7373 endothelial cells. In parallel, a pharmacological inhibition of protein kinase A (PKA) with N-[2-(p-bromocinnamylamino)ethyl]-5-isoquinolinesulfonamide dihydrochloride (H-89), antagonised the action of dipyridamole on gap junction coupling. We propose that the observed dipyridamole induced increase in gap junction coupling in endothelial cells is related to a