Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:B0FTZ7 (catenin)
 18,795 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The effect of hepatocyte growth factor/scatter factor (HGF/SF) and epidermal growth factor (EGF) on cadherin-mediated adhesion of human carcinoma cells was studied. HGF/SF induced scattering of colonic adenocarcinoma HT29 and gastric adenocarcinomas MKN7 and MKN74 cells. Likewise, EGF induced scattering of HT29 and MKN7 cells. These cells expressed E-cadherin, which was concentrated at cell-cell contact sites. When the scattering of these cells was induced by HGF/SF or EGF, the E-cadherin concentration at cell-cell boundaries tended to decrease. Immunoblotting analyses, however, demonstrated that these growth factor treatments did not alter the expression of E-cadherin and E-cadherin-associated proteins, alpha- and beta-catenin and plakoglobin. beta-Catenin, plakoglobin and an unidentified 115-kDa molecule associated with E-cadherin were found to be phosphorylated at tyrosine residues, and these phosphorylations were enhanced by the growth factor treatments. These results suggest that HGF/SF and EGF may modulate the function of the cadherin-catenin system via tyrosine phosphorylation of cadherin-associated proteins.
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PMID:Tyrosine phosphorylation of beta-catenin and plakoglobin enhanced by hepatocyte growth factor and epidermal growth factor in human carcinoma cells. 808 83

The cadherins are a family of transmembrane glycoproteins responsible for calcium-dependent cell-cell adhesion. This adhesion is mediated by a group of cytoplasmic proteins, the catenins, which act inside the cell to couple the cadherin molecule to the microfilament cytoskeleton. Dysfunction of E-cadherin-dependent cell-cell adhesion has been demonstrated to contribute to the acquisition of invasive potential of malignant adenocarcinoma cells. The potential role of alterations of catenin expression in tumor cell invasion is largely unexplored. We have previously found that E-cadherin is frequently down-regulated in clinical samples of prostate cancer (Umbas, R., Schalken, J. A., Aalders, T. W., Carter, B. S., Karthaus, H. F. M., Schaafsma, H. E., Debruyne, F. M. J., and Isaacs, W. B. Cancer Res., 52: 5104-5109, 1992). In this study, we further investigate this adhesion system in both benign and malignant human prostate cells in culture. Using antibodies to E-cadherin and its cytoplasmic accessory protein, alpha-catenin, we find that 5 of 6 human prostate cancer cell lines have reduced or absent levels of one or the other or both of these molecules when compared to normal prostatic epithelial cells. Only the LNCaP prostate cancer cell line is indistinguishable from normal prostate epithelium with respect to its E-cadherin-alpha-catenin complement. Interestingly, the PC-3 line is characterized by the presence of E-cadherin, but the complete lack of alpha-catenin found at both the RNA and protein level. This lack of alpha-catenin gene expression is explained by Southern analysis, which reveals a homozygous deletion of a large portion of the alpha-catenin gene in PC-3 cells. This loss of alpha-catenin is functionally manifested by negligible Ca(2+)-dependent aggregation of these cells in vitro, when compared to LNCaP cells. These results confirm that E-cadherin-dependent cell-cell adhesion is frequently aberrant in prostate cancer cells, and suggest that in a subset of prostate cancers, this adhesion may be inactivated by loss of alpha-catenin rather than E-cadherin itself. Furthermore, these results demonstrate that mutational inactivation of the alpha-catenin gene is one mechanism responsible for the loss of normal cell-cell adhesion in prostate cancer.
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PMID:Reduction of E-cadherin levels and deletion of the alpha-catenin gene in human prostate cancer cells. 833 65

The scenario of multistep of stomach carcinogenesis differs depending on the two histological types, well differentiated adenocarcinoma and poorly differentiated adenocarcinoma, because the two types may have different genetic pathways. Genetic instability, reactivation of telomerase and abnormal transcript of CD44 including intron 9 are common events of both well and poorly differentiated type carcinomas. These occur at early stage of carcinogenesis, even in precancerous lesions such as intestinal metaplasia and adenoma. Inactivation of APC, activation of K-ras, amplification of c-erbB2, and allelic loss of DCC locus are associated with well differentiated type, while amplification of K-sam and functional loss of cadherin/catenin are characteristics of poorly differentiated type. HGF/c-met system plays a pivotal role in morphogenesis of both histological types through interaction with cell-cell adhesion molecules. Reactivation of telomerase or genetic instability may be an initial event for accumulation of multiple genetic alterations during the progression of stomach carcinogenesis.
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PMID:[Genetic alterations in stomach cancer]. 869 39

DNA sequences encoding a novel member of the receptor protein tyrosine phosphatase (R-PTP) family, termed PCP-2, were identified in a human pancreatic adenocarcinoma cDNA library. Human PCP-2 cDNA predicts a protein of 1430 amino acids with a calculated Mr of 160 kDa. The predicted PCP-2 enzyme consists of a 740 amino acid extracellular region, a single transmembrane domain, and a 666 amino acid intracellular portion. The extracellular sequence contains a MAM (meprin/A5/PTPmu) domain, an immunoglobulin-like domain and four fibronectin type III-like repeats, suggesting that it is a member of the PTPkappa and PTPmu subfamily. The intracellular region contains two tandemly-repeated protein tyrosine phosphatase domains. Northern blot analyses revealed a single transcript of 5.5 kilobases, which is expressed at different levels in many human tissues except spleen and placenta. Upon transfection of PCP-2 cDNA into human embryonic kidney fibroblast 293 cells, a protein with an apparent Mr of 180 000 was detected by immunoblot analysis. This size was reduced to the predicted Mr upon treatment with endoglycosidase F, indicating that PCP-2 is glycosylated and, hence, expressed at the cell surface. A potential role of PCP-2 in cell-cell recognition and adhesion is supported by its co-localization with cell adhesion molecules, such as catenin and E-cadherin, at sites of cell-cell contact.
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PMID:Characterization of PCP-2, a novel receptor protein tyrosine phosphatase of the MAM domain family. 870 May 14

We previously presented a two-dimensional cell motility assay using L-10, a highly metastatic variant of the human rectal adenocarcinoma cell line RCM-1, as a motility model of tumor cells of epithelial origin. In this model, L-10 cells moved outward from the cell islands mainly as a localized coherent sheet of cells when stimulated with 12-O-tetradecanoylphorbol-13-acetate (TPA). Electronmicroscopic study of the migrating cell sheets revealed that wide intercellular gaps had developed at the lower portion of the cells, allowing them to extend leading lamellae, whereas close cell-cell contacts remained at the upper portion of the cells. In the present study, the mechanism involved in this localized modulation of cell-cell adhesion at the lower portion of the cells was investigated with special reference to E-cadherin expression. E-cadherin immunostaining, which was demonstrated using an anti-E-cadherin mAb, HECD-1, was decreased in migrating L-10 cell sheets. Apparently, however, E-cadherin was involved in the sheet formation of migrating cells because simultaneous or sequential treatment with TPA and HECD-1 inhibited sheet formation and caused scattering of migrating cells. With immunoelectron microscopic study, E-cadherin immunoreactivity was confined to the upper portion of migrating cells and lost at the lower portion. The level of E-cadherin and alpha-catenin expression was not altered by TPA treatment, although tyrosine phosphorylation of E-cadherin and catenins increased 1.6- to 1.9-fold. We propose that cells are released from cell-cell adhesion only at the lower portion of the cells via phosphorylation of the E-cadherin-catenin complex when stimulated with TPA. This change allows the cells to extend leading lamella and thus move together as coherent sheets (cohort migration).
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PMID:Modulation of E-cadherin expression in TPA-induced cell motility: well-differentiated human adenocarcinoma cells move as coherent sheets associated with phosphorylation of E-cadherin-catenin complex. 901 Apr 57

The integrity of the vascular endothelium is mainly dependent upon the organization of interendothelial adherens junctions (AJ). These junctions are formed by the homotypic interaction of a transmembrane protein, vascular endothelial cadherin (VE-cadherin), which is complexed to an intracellular protein network including alpha-, beta-, and gamma-catenin. Additional proteins such as vinculin and alpha-actinin have been suggested to link the VE-cadherin/catenin complex to the actin-based cytoskeleton. During the process of hematogenous metastasis, circulating tumor cells must disrupt these intercellular junctions in order to extravasate. In the present study, we have investigated the influence of tumor cell-endothelial cell interaction upon interendothelial AJ. We show that human breast adenocarcinoma cells (MCF-7), but not normal human mammary epithelial cells, induce a rapid endothelial cell (EC) dissociation which correlates with the loss of VE-cadherin expression at the site of tumor cell-EC contact and with profound changes in vinculin distribution and organization. This process could not be inhibited by metalloproteinase nor serine protease inhibitors. Immunoprecipitations and Western blot analysis demonstrate that the overall expression of VE-cadherin and vinculin as well as the composition of the VE-cadherin/catenins complex are not affected by tumor cells while the tyrosine phosphorylation status of proteins within the complex is significantly altered. Our data suggest that tumor cells modulate AJ protein distribution and phosphorylation in EC and may, thereby, facilitate EC dissociation.
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PMID:Alteration of interendothelial adherens junctions following tumor cell-endothelial cell interaction in vitro. 943 30

Loss of expression and function of the E-cadherin/catenin membrane complex can result in loss of cell adhesion and contribute to invasive or metastatic potential in carcinomas. The aim of this study was to examine the expression of alpha- and beta-catenin and E-cadherin in Barrett's esophagus with and without dysplasia and in esophageal adenocarcinomas and to identify any relationship with tumor growth pattern and clinical outcome. Immunoperoxidase staining for alpha- and beta-catenin and E-cadherin was performed on specimens of Barrett's esophagus with and without dysplasia and on 54 esophageal adenocarcinoma specimens. Membranous staining for all of the components was seen in normal gastric and esophageal mucosa. Abnormal expression of beta-catenin, alpha-catenin, and E-cadherin was significantly associated with higher degrees of dysplasia in Barrett's esophagus. Fourteen of 16 cases of high grade dysplasia and 7 of 7 cases of intramucosal carcinoma showed abnormal expression of beta-catenin, compared with 3 of 6 cases indefinite for dysplasia and 11 of 17 cases with low grade dysplasia (P = 0.022). Similar results were seen for expression of alpha-catenin (P < .01) and E-cadherin (P = .049). In esophageal adenocarcinomas, preserved expression of these proteins occurred more frequently in well-differentiated tumors; abnormal expression was more common in diffusely infiltrative poorly differentiated tumors that did not form glands. Focal nuclear staining for beta-catenin was present in two high-grade dysplasias, two intramucosal carcinomas, and five adenocarcinomas. No survival advantage was demonstrated for patients whose tumors retained expression of these cell adhesion components. In conclusion, abnormal expression of the E-cadherin/catenin membrane complex is common in esophageal adenocarcinoma and occurs early in the dysplasia/carcinoma sequence in Barrett's esophagus, indicating that disturbances in this cell adhesion complex might be important in tumorigenesis and tumor progression in this disorder.
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PMID:Expression of beta-catenin, alpha-catenin, and E-cadherin in Barrett's esophagus and esophageal adenocarcinomas. 975 59

We have already presented a two-dimensional cell motility assay using a highly metastatic variant (L-10) of human rectal adenocarcinoma cell line RCM-1 as a motility model of tumour cells of epithelial origin. In this model, L-10 cells showed locomotion as a coherent sheet when stimulated with 12-O-tetradecanoylphorbol-13-acetate (TPA), and we called this type of movement "cohort migration". Electron and immunoelectron microscopic study of the migrating cell sheets demonstrated localized release from cell-cell adhesion only at the lower portion of the cells with loss of E-cadherin immunoreactivity, and this change was associated with increased tyrosine phosphorylation of the E-cadherin-catenin complex, including beta-catenin. Cell-extracellular matrix (ECM) interactions involved in this TPA-induced cohort migration and their effect on tyrosine phosphorylation of the E-cadherin-catenin complex have now been investigated. L-10 cell cohort migration was almost completely inhibited by addition of Arg-Gly-Asp (RGD) peptide into the medium, and thus RGD dependent. Cohort migration was stimulated on type I and IV collagens, fibronectin (FN)- and laminin-coated substratum, but was inhibited by RGD only on FN-coated surface. By using immunofluorescent techniques, FN was demonstrated preferentially around migrating cells, and a protein synthesis inhibitor, cycloheximide, inhibited the migration by about 75%. FN produced by L-10 cells were found to be mostly EDA+ FN when analysed by RT-PCR. Moreover, anti-FN antibody, but not anti-vitronectin antibody, inhibited the TPA-induced cohort migration almost completely. Thus, it was likely that L-10 cells produced FN themselves and moved on the FN substrate in an RGD-dependent manner. However, stimulation of migration by type I collagen coating and inhibition by RGD treatment did not affect the tyrosine phosphorylation of the E-cadherin-catenin complex induced by TPA, indicating that cell-cell interactions were adjusted to suit cell migration, irrespective of the condition of cell-ECM adhesion, during TPA-induced cohort migration.
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PMID:TPA-induced cohort migration of well-differentiated human rectal adenocarcinoma cells: cells move in a RGD-dependent manner on fibronectin produced by cells, and phosphorylation of E-cadherin/catenin complex is induced independently of cell-extracellular matrix interactions. 976 28

Bronchioloalveolar carcinoma (BAC) has features distinct from those of conventional pulmonary adenocarcinoma (CPA) in terms of its characteristic growth pattern along alveolar walls and intrapulmonary metastasis via the aerogenous route. We speculated, therefore, that BAC might differ from CPA in its capacity for cell-to-cell or cell-to-basement membrane adhesion. E-cadherin (E-CD), one of the most important elements of epithelial integrity molecules, is related to tumor metastasis in various organs. Differences of E-CD and associated catenin expressions between BAC and CPA, however, have not been elucidated. We examined the expression of E-CD and alpha-, beta- and gamma-catenin immunohistochemically in 18 BACs (9 mucinous, 7 nonmucinous, and 2 sclerosing) in comparison with CPAs, all of which were well-differentiated adenocarcinomas. In addition, we analyzed the correlation between the expression of these cell adhesion molecules and the presence of intrapulmonary metastasis, histologic subtypes, and cell proliferation activity. Clinicopathologically, we observed intrapulmonary metastases in 4 of the 18 BACs and none of the CPAs. In 14 of the 18 BACs, more than one-half of the tumor cells expressed E-CD, and the E-CD expression level was significantly higher in the BACs than in the CPAs. In addition, all of the BACs exhibited preserved membranous staining for E-CD, whereas in 5 of the 14 CPAs, the expression pattern was disorganized cytoplasmic staining; the difference was statistically significant. The Ki-67 labeling index was significantly lower in the BACs than in the CPAs. There were no appreciable differences in E-CD expression among the BAC subtypes. E-CD expression was significantly lower in the BACs with intrapulmonary metastasis than in the BACs without intrapulmonary metastasis. These findings indicated to us that BAC was distinct from CPA in terms of proliferation activity and expression of certain adhesion molecules and that E-CD downregulation was associated with a tendency toward intrapulmonary metastasis.
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PMID:Expression of E-cadherin, alpha-catenin, beta-catenin, and gamma-catenin in bronchioloalveolar carcinoma and conventional pulmonary adenocarcinoma: an immunohistochemical study. 983 Nov 99

We presented earlier a 2-dimensional cell-motility assay using a highly metastatic variant (L-10) of human rectal-adenocarcinoma cell line RCM-1 as a motility model of tumor cells of epithelial origin. In this model, L-10 cells moved as coherent cell sheets when stimulated with 12-O-tetradecanoylphorbol-13-acetate (TPA), and we called this type of movement "cohort migration". Electron- and immunoelectron-microscope study of the migrating cell sheets demonstrated localized release from cell-cell adhesion only at the lower portion of the cells with loss of E-cadherin immunoreactivity, and this change was associated with increased tyrosine phosphorylation of the E-cadherin-catenin complex, including beta-catenin. In the present study, to obtain evidence to support the relevance of our model to carcinoma-cell movement in vivo, we sought a naturally occurring motogenic factor(s) able to induce this cohort migration. Among the factors examined, hepatocyte growth factor/scatter factor (HGF/SF) clearly induced cohort migration of L-10 cells. Additionally, not only L-10 but several other human colorectal-carcinoma cell lines showed this type of migration in response to HGF/SF, while yet others showed scattering-type motility. In this HGF/SF-induced migration, localized release from cell-cell adhesion was induced only at the lower portion of the cells, allowing them to extend leading lamellae, whereas close cell-cell contacts remained at the upper portion of the cells, as seen in TPA-induced cohort migration. Scattering-type cell lines tended to express more c-Met (receptor for HGF/SF) mRNA than the cell lines that showed cohort-type migration. LoVo, one of the scattering-type cell lines, expressed more c-Met protein and less E-cadherin than L-10, which showed cohort-type migration. HGF/SF treatment of LoVo reduced the amount of alpha-catenin complexed with E-cadherin more markedly than in L-10, but in both cell lines this reduction was not accompanied by increased tyrosine phosphorylation of beta-catenin, suggesting the presence of a mechanism other than phosphorylation for release from cell-cell adhesion during cell motility.
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PMID:Hepatocyte growth factor/scatter factor induces not only scattering but also cohort migration of human colorectal-adenocarcinoma cells. 983 69


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