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)

Rat 3Y1 cells acquire metastatic potential when transformed with v-src, and this potential is enhanced by double transformation with v-src and v-fos (Taniguchi, S., T. Kawano, T. Mitsudomi, G. Kimura, and T. Baba. 1986. Jpn. J. Cancer Res. 77:1193-1197). We compared the activity of cadherin cell adhesion molecules of normal 3Y1 cells with that of v-src transformed (SR3Y1) and v-src and v-fos double transformed (fosSR3Y1) 3Y1 cells. These cells expressed similar amounts of P-cadherin, and showed similar rates of cadherin-mediated aggregation under suspended conditions. However, the aggregates or colonies of these cells were morphologically distinct. Normal 3Y1 cells formed compacted aggregates in which cells are firmly connected with each other, whereas the transformed cells were more loosely associated, and could freely migrate out of the colonies. Overexpression of exogenous E-cadherin in these transformed cells had no significant effect on their adhesive properties. We then found that herbimycin A, a tyrosine kinase inhibitor, induced tighter cell-cell associations in the aggregates of the transformed cells. In contrast, vanadate, a tyrosine phosphatase inhibitor, inhibited the cadherin-mediated aggregation of SR3Y1 and fosSR3Y1 cells but had little effect on that of normal 3Y1 cells. These results suggest that v-src-mediated tyrosine phosphorylation perturbs cadherin function directly or indirectly, and the inhibition of tyrosine phosphorylation restores cadherin action to the normal state. We next studied tyrosine phosphorylation on cadherins and the cadherin-associated proteins, catenins. While similar amounts of catenins were expressed in all of these cells, the 98-kD catenin was strongly tyrosine phosphorylated only in SR3Y1 and fosSR3Y1 cells. Cadherins were also weakly tyrosine phosphorylated only in the transformed cells. The tyrosine phosphorylation of these proteins was enhanced by vanadate, and inhibited by herbimycin A. Thus, the tyrosine phosphorylation of the cadherin-catenin system itself might affect its function, causing instable cell-cell adhesion.
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PMID:Cadherin-mediated cell-cell adhesion is perturbed by v-src tyrosine phosphorylation in metastatic fibroblasts. 163 52

The cytoplasmic region of the Ca(2+)-dependent cell-adhesion molecule (CAM) uvomorulin associates with distinct cytoplasmic proteins with molecular masses of 102, 88, and 80 kDa termed alpha, beta, and gamma catenin, respectively. This complex formation links uvomorulin to the actin filament network, which seems to be of primary importance for its cell-adhesion properties. We show here that antibodies against alpha catenin also immunoprecipitate complexes that contain human N-cadherin, mouse P-cadherin, chicken A-CAM (adherens junction-specific CAM; also called N-cadherin) or Xenopus U-cadherin, demonstrating that alpha catenin is complexed with other cadherins. In immunofluorescence tests, alpha catenin is colocalized with cadherins at the plasma membrane. However, in cadherin-negative Ltk- cells, alpha catenin is found uniformly distributed in the cytoplasm, suggesting some additional biological function(s). Expression of uvomorulin in these cells results in a concentration of alpha catenin at membrane areas of cell contacts. We also have cloned and sequenced murine alpha catenin. The deduced amino acid sequence reveals a significant homology to vinculin. Our results suggest the possibility of a new vinculin-related protein family involved in the cytoplasmic anchorage of cell-cell and cell-substrate adhesion molecules.
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PMID:The uvomorulin-anchorage protein alpha catenin is a vinculin homologue. 192 79

Transfection of E- and P-cadherin cDNA has been carried out in murine spindle carcinoma cells previously shown to be deficient in both cadherins (Navarro et al., J. Cell Biol. 115, 517-533, 1991). High levels of expression of E- or P-cadherin do not significantly affect the fibroblastic morphology of the parental spindle cells. In addition, the tumorigenic behavior of these highly malignant cells is not influenced by the ectopic expression of either cadherin. Nevertheless, a fraction of the exogenous cadherins is able to associate to detergent-insoluble components of the transfectant cells, and the expression of the exogenous E-cadherin confers Ca(2+)-dependent aggregation on the spindle transfectants in an in vitro assay. Immunoprecipitation analysis of the cadherin-catenin complex of the transfectants revealed that the ectopic E-cadherin associates with the alpha- and beta-catenin proteins. However, the gamma-catenin/plakoglobin component could not be detected in the E-cadherin immunocomplexes of the spindle transfectant cells, in contrast to the epithelial cells where the three catenins appeared to be associated with E-cadherin. The lack of association of gamma-catenin is correlated with very low levels of plakoglobin in whole cell extracts of the parental spindle cells. These results indicate that the association of E-cadherin with the alpha- and beta-catenin components is not sufficient to promote a fibroblastoid-epithelial conversion of highly malignant spindle cells. The presence of plakoglobin could be required for the proper organization of E-cadherin in the transfectant cells in order to acquire an epithelioid phenotype.
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PMID:Expression of E- or P-cadherin is not sufficient to modify the morphology and the tumorigenic behavior of murine spindle carcinoma cells. Possible involvement of plakoglobin. 822 14

E- and P-cadherin are members of a family of calcium-dependent, cell surface glycoproteins involved in cell-cell adhesion. Extracellularly, the transmembrane cadherins self-associate, while intracellularly, they interact with the actin-based cytoskeleton. Several intracellular proteins, collectively termed catenins, are tightly associated with E- and P-cadherin. These proteins appear to link the cadherin to the cytoskeleton and have been proposed to be involved in concentrating cadherins at cell-cell adherens junctions. In this paper we report the production of monoclonal antibodies against both alpha- and beta-catenin and use these antibodies to show that in cells simultaneously expressing two different cadherins, E-cadherin and P-cadherin, each cadherin appears to be present in a separate cadherin/catenin complex.
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PMID:P- and E-cadherin are in separate complexes in cells expressing both cadherins. 834 78

Cadherins are a family of calcium-dependent cell-cell adhesion molecules involved in cell-cell aggregation and morphoregulatory cell function. Dysfunction of the cadherin pathway is involved in tumour invasiveness and disease progression for a variety of carcinomas. E-cadherin is a prognostic marker in prostatic cancer, based on the correlation of the grade of E-cadherin expression and tumour grade, stage, metastasis and survival, as well as recurrence after radical prostatectomy. P-cadherin was shown to be lost in all prostatic cancers, although this most likely reflects loss of the basal cell population rather than a transcriptional down-regulation, suggesting that loss of P-cadherin expression is an early event in the tumorigenesis of prostatic carcinomas. Catenins, particularly alpha-catenin, also play an important role in the dysfunction of the cell adhesion complex. Mechanisms of inactivation of the cadherin-catenin pathway include LOH, gene deletions and gene promoter hypermethylation. Therapeutic strategies have been investigated in tumour models, i.e. the use of demethylating agents for the hypermethylated promoter region of E-cadherin or gene transfer in PC-3 cells with homozygous deletion of the alpha-catenin gene. The complexity of neoplastic changes cannot be explained by alterations of cell adhesion molecules alone; but as demonstrated, cadherins and catenins play an important role in this process.
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PMID:The cadherin cell-cell adhesion pathway in prostate cancer progression. 908 71

The immunocytochemical expression of cadherins and catenins was examined during the process of oral carcinogenesis by comparing their expression in normal and dysplastic epithelium with primary and metastatic carcinomas. While control epithelium showed normal distribution for P and E cadherin and the catenins, in severe dysplasia P-cadherin was upregulated. In other cases and in carcinoma-in-situ adjacent to infiltrating carcinomas, membranous expression of the cadherins and catenins was reduced or lost. The changes in expression of E-cadherin and the catenins suggest that disruption of the E-cadherin/catenin complex is a late event associated with invasion. In primary carcinomas reduced membranous and cytoplasmic staining were observed for both cadherins and catenins. Abnormal localisation of E-cadherin occurred in the more superficial parts of the better differentiated carcinomas, suggesting abnormality to the E-cadherin complex(es). In contrast, membranous expression of cadherins and catenins was reduced or lost in the deep invasive margin of primary carcinomas and in most poorly differentiated carcinomas. For E-cadherin at least, this reduction appears associated with differentiation, invasion and possibly prognosis. Possible mechanisms involved for changes in expression of the cadherins and associated catenins and areas for further study are discussed.
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PMID:Expression of cadherins and catenins in oral epithelial dysplasia and squamous cell carcinoma. 972 68

The cadherins are major mediators of calcium-dependent cell-cell adhesion and are also involved in cell signaling pathways during development. The classical cadherins, which are the definitive group of the cadherin superfamily, are transmembrane proteins that consist of an extracellular domain of five cadherin repeats, including an HAV tripeptide conserved in one binding surface within the first domain, and a highly conserved cytoplasmic domain that interacts with the actin cytoskeleton via the catenin proteins. These cadherins play major roles in vertebrate morphogenesis; they are expressed widely throughout development, antibodies to specific cadherins perturb a variety of developmental processes, and many gene knockouts are lethal at early stages of development. Phylogenetic analysis of the "classical" cadherins shows that in the vertebrates there are four paralog families. The rate of evolutionary change is radically different between the different paralogs, indicating that there are significantly different selection pressures on the functions of the various cadherins, both between the different paralogs in a single organism lineage and between different organism lineages within a single paralog family. There is also evidence for gene conversion between the E-cadherin and P-cadherin paralogs in Gallus gallus and possibly Xenopus laevis, but not between the same paralogs in the mammalian lineages. A scheme for the origin of the paralogs within the vertebrate lineage based on these analyses indicates that the presence of the four paralog families is a characteristic of vertebrates and that variation of cadherin structure and function is a significant factor in morphological evolution of vertebrates.
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PMID:Evolution of the "classical" cadherin family of cell adhesion molecules in vertebrates. 972 74

The cadherin/catenin complexes expressed by a murine epidermal keratinocyte cell line PDV, expressing E- and P-cadherin, have been analysed using a combination of biochemical and confocal microscopy analysis. Two types of E-cadherin complexes, containing beta-catenin or plakoglobin and alpha-catenin, were detected in PDV cells as in other cell types, while P-cadherin was mainly detected in complexes containing beta-catenin and alpha-catenin in PDV and other murine epidermal keratinocytes. Biotin-labelling studies have shown that both types of E-cadherin complexes are present at the surface of confluent cells. Furthermore, confocal microscopy analysis indicated that E-cadherin/plakoglobin complexes are located in stable cell-cell contacts at the middle lateral membranes and associated with alpha-catenin and the actin cytoskeleton, with a similar distribution to that to the E-cadherin/beta-catenin complexes. In addition, E-cadherin/plakoglobin complexes not associated with alpha-catenin or the actin cytoskeleton were detected in lower planes of the lateral contacting membranes as well as E-cadherin non-associated with catenins in the more basal planes. These studies support that in murine epidermal keratinocytes both beta-catenin- and plakoglobin-containing E-cadherin complexes contribute to the maintenance of stable cell-cell contacts and suggest a differential role of the plakoglobin containing complexes in different epithelial cell types.
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PMID:Cadherin/catenin complexes in murine epidermal keratinocytes: E-cadherin complexes containing either beta-catenin or plakoglobin contribute to stable cell-cell contacts. 975 21

Maintenance of an adhesive function for cadherins requires appropriate membranous cellular expression and intact cadherin-catenin complexes. In normal squamous mucosa of the oesophagus there is membranous co-expression of E- and P-cadherin (E-cad, P-cad) in the basal compartment, whereas suprabasal stratification is associated with preservation of E-cad expression but loss of P-cad. Immunohistochemical staining of squamous dysplasia/carcinoma in situ shows a striking increase in the proportion of cells within the epithelial compartment showing co-expression of E- and P-cad with strong appropriate membranous expression of beta and gamma catenin. Strong membranous co-expression of E- and P-cad and beta catenin is seen on keratinocytes at the periphery of islands of invasive better-differentiated squamous carcinoma with keratinisation, mimicking normal mucosa. Beta catenin may be phosphorylated with implied loss of cadherin binding. Membranous cadherin and catenin expression is significantly down-regulated in poorly differentiated squamous carcinoma. No beta catenin mutations were demonstrated in squamous carcinomas following DNA extraction and sequencing, nor was any nuclear cadherin seen. Changes in cadherin-catenin complexes with cellular phenotype is well demonstrated in spindle cell carcinomas with a shift of cadherin expression from membranous to cytoplasmic between the epithelioid and spindle cell components of the tumour and with loss of expression in the sarcomatoid elements. In conclusion, we demonstrate an increased expression of P-cadherin early in tumourigenesis with loss of cadherin-catenin complexes in poorly differentiated invasive carcinomas. Cadherin/catenin expression may govern both the phenotype and biology of oesophageal squamous carcinomas.
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PMID:Sequential changes in cadherin-catenin expression associated with the progression and heterogeneity of primary oesophageal squamous carcinoma. 984 64

We are investigating the hypothesis that cancer progression involves the formation of abnormal cadherin-catenin complexes. The detailed analysis of cadherins and catenins expressed in a panel of 17 human bladder-cancer cell lines revealed that E-cadherin was down-regulated at the mRNA level in 5 cell lines. Interestingly, plakoglobin was also down-regulated at the mRNA level in these 5 cell lines only. Furthermore, a slower migrating form of pp120 was detected in these cell lines and in 2 cell lines with heterogeneous E-cadherin expression. Cloning of the cadherins expressed in the bladder lines revealed that P-cadherin is expressed in the lines expressing E-cadherin and down-regulated at the mRNA level in lines devoid of E-cadherin. N-cadherin was expressed in the 5 lines with reduced E-cadherin expression, in the 2 lines with heterogeneous E-cadherin expression and in 2 other cell lines. Thus, we showed that catenin changes occur in correlation with lack of E-cadherin expression and that N-cadherin becomes predominantly expressed in cells that have lost E-cadherin expression. Our data suggest that co-regulation of the expression of genes encoding different members of the classical cadherins occurs during tumor progression and that expression of some catenins is also coordinated with cadherin expression.
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PMID:Changes in cadherin-catenin complexes in the progression of human bladder carcinoma. 1036 Aug 23


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