Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P06889 (Mol)
 630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The classical cadherins are homophilic binding molecules that play fundamental roles in several biological processes, including axonal growth and synaptic plasticity. The structures of the amino-terminal homophilic binding domains of N-cadherin and E-cadherin have been resolved. However, the mechanisms that govern cadherin binding and specificity remain contentious. In the present study we have used a peptide competition approach to probe for small linear determinants of cadherin binding. We demonstrate that a linear peptide mimetic of a short sequence in ECD1 of N-cadherin (INPISGQ) functions as a highly specific and potent antagonist of N-cadherin function with an IC(50) value of approximately 15 microM. Peptide mimetics of the corresponding motif in chick R-cadherin also inhibited N-cadherin function, albeit with lower efficacy. In contrast, peptide mimetics of the corresponding motif in E- or P-cadherin failed to inhibit N-cadherin function. A short cyclic peptide that contained only the INP motif from N-cadherin was also a potent N-cadherin antagonist (IC(50) approximately 15 microM). Analysis of existing crystal structures suggests that the peptides are likely to antagonize N-cadherin function by binding to the region that flanks the HAV motif at the adhesion dimer interface.
Mol Cell Neurosci 2000 May
PMID:INP, a novel N-cadherin antagonist targeted to the amino acids that flank the HAV motif. 1083 2

Indole-3-carbinol (I3C) is a compound occurring naturally in cruciferous vegetables and has been indicated as a promising agent in preventing breast cancer development and progression. In the present study we have investigated the effect of I3C on the cell migration and invasion behavior in estrogen receptor positive MCF-7 and estrogen receptor negative MDA-MB-468 human breast cancer cell lines. Both MCF-7 and MDA-MB-468 were poorly invasive cell lines and exhibited modest invasion and migration capacity in the presence of fibronectin as the chemoattractant. I3C (50 or 100 microM) elicited a significant inhibition of in vitro cell adhesion, migration, and invasion as well as in vivo lung metastasis formation in both cell lines. I3C also suppressed the 17beta-estradiol stimulated migration and invasion in estrogen-responsive MCF-7 cells. These results indicate that anti-invasion and antimigration activities of I3C occur via estrogen-independent and estrogen-dependent pathways. Moreover, I3C significantly caused a dose-dependent increase in E-cadherin, three major catenins (alpha, beta, and gamma-catenin) and BRCA1 expression. Our current finding is the first demonstration that I3C can activate the function of invasion suppressor molecules associated with the suppression of invasion and migration in breast cancer cells. Thus, clinical application of I3C may contribute to the potential benefit for suppression of breast cancer invasion and metastasis.
J Mol Med (Berl) 2000
PMID:Suppression of breast cancer invasion and migration by indole-3-carbinol: associated with up-regulation of BRCA1 and E-cadherin/catenin complexes. 1086 78

Endometriosis is defined as endometriotic tissues growing outside the uterine cavity. The cell biological processes responsible for the pathogenesis of this disease are not well understood. In order to detect differences in proliferative activity between endometria and endometriotic lesions, Ki67 staining was analysed. In addition, expression of epidermal growth factor (EGF) and its receptor was examined using immunohistochemistry. For dedifferentiation processes pointing to invasive properties of the uterine epithelium, the presence of the adhesion complex E-cadherin with the associated alpha- and beta-catenin was investigated. Specimens of endometrium in the proliferative phase of 36 patients without, and 79 patients with, endometriosis together with endometriotic lesions were studied. The study revealed a significantly reduced proliferation activity in uterine epithelium within the ectopic lesions but no differences between eutopic endometria of non-affected and affected patients. Furthermore, a lower expression of both EGF and its receptor in the epithelial cells of the ectopic glands was observed. The adhesion complex E-cadherin, together with alpha-, and beta-catenin, was slightly reduced in uterine epithelial cells of women with endometriosis and less expressed in endometriotic lesions. The results indicate that epithelial cells of endometriotic lesions are not hyperproliferative, but do appear to dedifferentiate, displaying an invasive character.
Mol Hum Reprod 2000 Jul
PMID:Reduced proliferation and cell adhesion in endometriosis. 1087 48

E-cadherin is a transmembrane glycoprotein which mediates a calcium dependent homophilic interaction among epithelial cells. The altered expression and gene mutations of E-cadherin adhesion molecule have been frequently observed in various tumors. Several invasive carcinomas showed cell-cell adhesion loss although the tumor cells expressed considerable amounts of E-cadherin protein. The purpose of this study was to evaluate the role of E-cadherin gene alterations in genesis and progression of bladder carcinoma by mutation analysis of coding region, expression analysis and microsatellite instability at E-cadherin chromosome locus. We analyzed 30 bladder carcinoma (28 transitional and 2 squamous cell carcinoma) at different stage and grade. The mutation analysis showed that in one case there was a presence of a point mutation at codon 846 that consisted of a G (AGC) to C (ACC) transversion resulting in the replacement of R to T. In another sample the sequence analysis revealed a same-sense mutation at the codon 785 (AAC - AAT). The study of E-cadherin mRNA by Northern blot analysis showed that there were no differences of mRNA levels between tumor and normal mucosa samples. We noted that invasive and anaplastic tumors showed a trend to loss of expression, even if we did not find any statistically significant differences. The microsatellite analysis showed the presence of genomic instability in proximity of the E-cadherin gene. Nine out of 30 (30%) specimens presented molecular alterations in at least one out of 2 loci (D16S260 and D16S301) analyzed. The comparison between microsatellite mutations and clinical-histopathological parameters revealed a higher number of alterations in invasive respect to superficial tumors (p=0.014). On the other hand, there were no statistical differences regarding the correlation with pathological grade. These observations, which, nevertheless, need to be confirmed in a larger number of patients, suggest that alterations of E-cadherin gene may be related to pathobiology of bladder cancer development and clinical progression.
Int J Mol Med 2000 Aug
PMID:Molecular alterations of E-cadherin gene: possible role in human bladder carcinogenesis. 1089 67

Processing of latent precursor proteins by proprotein convertases (PCs) into their biologically active products is a common mechanism required for many important biologic functions. This process is tightly regulated, leading to the generation of active peptides and proteins including neuropeptides and polypeptide hormones, protein tyrosine phosphatases, growth factors and their receptors, and enzymes including matrix metalloproteases (MMPs). These processing reactions occurs at pairs of basic amino acids. Within the past several years, a novel family of Ca(2+)-dependent serine proteases has been identified, all of which possess homology to the endoproteases subtilisin (bacteria) and kexin (yeast). This family of PCs is currently comprised of fewer than a dozen members, known as furin/paired basic amino-acid-cleaving enzyme (PACE), PC1/PC3, PC2, PC4, PACE4, PC5/PC6, and PC7/PC8/lymphoma proprotein convertase. They share a high degree of amino-acid identity of 50-75% within their catalytic domains. Despite the relatively high degree of homology in the PC family, only PACE4 and furin localize to the same chromosome: mouse chromosome 7 and human chromosome 15. Recent reports have supported a possible functional role for PCs in tumorigenesis. For instance, convertases have been shown to be expressed in various tumor lines and human primary tumors. Furin and PACE4 process stromelysin 3 (MMP-11 or Str-3), an MMP involved in tumor invasion, into its mature, active form. Similarly, a growing family of MMPs, known as membrane-type metalloproteinases (MT-MMPs), and growth factors and adhesion molecules such as E-cadherin show similar amino-acid motifs and thus could be activated by furin and PACE4. These data, taken together with the high expression levels of PACE4 in 50% of murine chemically induced spindle cell tumors, confer to PACE4 and possibly other PCs a possible functional role in the activation of MMPs and consequently in tumor cell invasion and tumor progression. This was further supported by the remarkable enhancement in the invasive ability of the PACE4-transfected murine tumor cell lines. Mol. Carcinog. 28:63-69, 2000.
Mol Carcinog 2000 Jun
PMID:The proprotein convertases furin and PACE4 play a significant role in tumor progression. 1090 Apr 62

The role of platelet endothelial cell adhesion molecule-1 (PECAM-1) in endothelial cell-cell interactions and its contribution to cadherin-mediated cell adhesion are poorly understood. Such studies have been difficult because all known endothelial cells express PECAM-1. We have used Madin-Darby canine kidney (MDCK) cells as a model system in which to evaluate the role of PECAM-1 isoforms that differ in their cytoplasmic domains in cell-cell interactions. MDCK cells lack endogenous PECAM-1 but form cell-cell junctions similar to those of endothelial cells, in which PECAM-1 is concentrated. MDCK cells were transfected with two isoforms of murine PECAM-1, Delta15 and Delta14&15, the predominant isoforms expressed in vivo. Expression of the Delta15 isoform resulted in apparent dedifferentiation of MDCK cells concomitant with the loss of adherens junctions, down-regulation of E-cadherin, alpha- and beta-catenin expression, and sustained activation of extracellular regulated kinases. The Delta15 isoform was not concentrated at cell-cell contacts. In contrast, the Delta14&15 isoform localized to sites of cell-cell contact and had no effect on MDCK cell morphology, cadherin/catenin expression, or extracellular regulated kinase activity. Thus, the presence of exon 14 in the cytoplasmic domain of PECAM-1 has dramatic effects on the ability of cells to maintain adherens junctions and an epithelial phenotype. Therefore, changes in the expression of exon 14 containing PECAM-1 isoforms, which we have observed during development, may have profound functional consequences.
Mol Biol Cell 2000 Aug
PMID:Differential modulation of cadherin-mediated cell-cell adhesion by platelet endothelial cell adhesion molecule-1 isoforms through activation of extracellular regulated kinases. 1093 Apr 70

Previous reports have described down-regulation of E-cadherin in trophoblasts differentiating to an invasive phenotype. This study shows the localization of E-cadherin in a prospective design with stereological sampling of fetal and maternal first, second and third trimester tissue. E-cadherin was observed in villous cytotrophoblasts, and in non-proliferating, intermediate trophoblasts (IT) within cell columns and islands in intrauterine, ectopic and partial molar placentas. Highly proliferating IT with cytological atypia in complete molar placentas were also E-cadherin-positive. E-cadherin was present in trophoblasts throughout the anchoring cell columns. Trophoblasts undergoing epithelial mesenchymal transformation (EMT) detaching from the distal cell columns and deeper located single extravillous interstitial trophoblasts (EVT) showed E-cadherin-negative breaches in the cell membrane. Prior to the late second trimester, the relative number of E-cadherin-positive single EMT and EVT differed from the total number of cytokeratin-positive trophoblasts. Intraluminal, endovascular and perivascular trophoblasts adjacent to the maternal vessels were also E-cadherin-positive, but a highly varying pattern was observed at different ages of gestation. Our results indicate a temporary shift in E-cadherin expression in extravillous trophoblasts possessing a migrating and invasive potential. Functional E-cadherin may be restored as trophoblasts aggregate in the decidua and the vessel wall after completion of migration.
Mol Hum Reprod 2000 Oct
PMID:Localization of E-cadherin in villous, extravillous and vascular trophoblasts during intrauterine, ectopic and molar pregnancy. 1100 24

beta-Catenin promotes epithelial architecture by forming cell surface complexes with E-cadherin and also interacts with TCF/LEF-1 in the nucleus to control gene expression. By DNA transfection, we overexpressed beta-catenin and/or LEF-1 in NIH 3T3 fibroblasts, corneal fibroblasts, corneal epithelia, uveal melanoma cells, and several carcinoma cell lines. In all cases (with or without LEF-1), the abundant exogenous beta-catenin localizes to the nucleus and forms distinct nuclear aggregates that are not associated with DNA. Surprisingly, we found that with time (5-8 d after transfection) cells overexpressing beta-catenin all undergo apoptosis. LEF-1 does not need to be present. Moreover, LEF-1 overexpression in the absence of exogenous beta-catenin does not induce apoptosis, even though some endogenous beta-catenin moves with the exogenous LEF-1 into the nucleus. TOPFLASH/FOPFLASH reporter assays showed that full-length beta-catenin is able to induce LEF-1-dependent transactivation, whereas Arm beta-catenin totally abolishes the transactivating function. However, Arm beta-catenin, containing deletions of known LEF-1-transactivating domains, has the same apoptotic effects as full-length beta-catenin. Overexpressed beta-catenin also induces apoptosis in cells transfected with nuclear localization signal-deleted LEF-1 that localizes only in the cytoplasm. Thus, the apoptotic effects of overexpressed exogenous beta-catenin do not rely on its transactivating function with nuclear LEF-1. Overexpressed delta-catenin, containing 10 Arm repeats, induces only minor apoptosis, suggesting that the major apoptotic effect may be due to domains specific to beta-catenin as well as to Arm repeats. The absence of p53, Rb, cyclin D1, or E2F1 does not affect the apoptotic effect of overexpressed beta-catenin, but Bcl-x(L) reduces it. We hypothesize that in vivo apoptosis of cells overexpressing beta-catenin might be a physiological mechanism to eliminate them from the population.
Mol Biol Cell 2000 Oct
PMID:Overexpression of beta-catenin induces apoptosis independent of its transactivation function with LEF-1 or the involvement of major G1 cell cycle regulators. 1102 52

Epithelial intercellular adhesion is fundamental to the formation of the airway epithelial protective barrier. In this respect, cadherins are important because these adhesion molecules regulate formation and maintenance of epithelial intercellular junctions. To study the importance of airway epithelial integrity in determining susceptibility to virus infection, we used a replication-incompetent adenovirus, RAd35, and an E-cadherin specific function-blocking antibody, SHE78-7, to disrupt intercellular contacts in human bronchial epithelial cell line 16HBE14o- and primary bronchial epithelial cells. After exposure of 16HBE14o- cell cultures to SHE78-7, disruption of the transepithelial permeability barrier was indicated by a loss of transepithelial electrical resistance and an associated increase of mannitol, inulin, and dextran paracellular flux. Subsequent exposure of SHE78-7-treated cell cultures to RAd35 showed a remarkable increase in adenoviral infection as assessed by beta-galactosidase reporter gene expression. In cultures exposed to SHE78-7, disruption of E-cadherin function resulted in infection equivalent to that in control cultures using 16-fold lower viral titers. These studies show that manipulation of E-cadherin function provides a specific means of altering epithelial integrity that in turn determines resistance of airway epithelia to adenoviral infection.
Am J Respir Cell Mol Biol 2000 Nov
PMID:Loss of epithelial integrity resulting from E-cadherin dysfunction predisposes airway epithelial cells to adenoviral infection. 1106 39

The airway epithelium plays a critical role in asthma. E-cadherin, located on the basolateral side of the epithelial cells, forms adherent junctions. To investigate the role of E-cadherin on the regulation of permeability of molecules and fluid in asthmatic responses, we observed the dynamics of E-cadherin after an immunochallenge against guinea pigs. Immunohistochemical studies revealed that E-cadherin was expressed on the lateral sides of epithelial cells before the immunochallenge and after immediate airway responses (IAR). However, E-cadherin immunoreactivities decreased from the basolateral region in late airway responses (LAR) 6 h after the challenge. Simultaneously, soluble E-cadherin immunoreactivities were detected in lavage fluid only in LAR, suggesting that E-cadherin is partly cleaved and released into the lumen in LAR. Airway permeability, which was examined by penetration of horseradish peroxidase from the airway side into the epithelium, increased in both IAR and LAR. These results suggest that E-cadherin detachment from the lateral side of the epithelial cells increased airway permeability in LAR but not IAR. We conclude that an antigen challenge causes an opening of adherent junctions as well as increases airway permeability in LAR. This mechanism would participate in airflow limitation during attacks and the increase of airway permeability and hyperresponsiveness in asthmatics.
Am J Respir Cell Mol Biol 2000 Dec
PMID:Dislocation of E-cadherin in the airway epithelium during an antigen-induced asthmatic response. 1110 22


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>