Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0677930 (primary tumor)
 20,210 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cadherin and catenin compose cell adhesion complex and are indispensable for tight cell-cell adhesion. Dysfunction of this adhesion complex causes dissociation of cancer cells from primary tumor nodules, thus possibly contributing to cancer invasion and metastasis. In this report, we present the human alpha-catenin sequence. Human alpha-catenin showed extensive homology with that of mouse, i.e., 91.8% and 99.3% at the nucleic acid and amino acid levels, respectively, indicating that this molecule has been evolutionarily conserved in mammals. Characterization of the mRNA sequence of alpha-catenin in PC9 was also carried out, and two distinct abnormal sequences, i.e., one of 957 bp deletion resulting in a 319-amino-acid deletion and another of 761 bp deletion resulting in a frameshift, were identified. These deletions were probably produced by an error of RNA splicing, presenting one possible mechanism for the loss of intact alpha-catenin expression.
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PMID:Cloning of the human alpha-catenin cDNA and its aberrant mRNA in a human cancer cell line. 832 64

Little is known about the role of molecules involved in cell-cell interactions during the progression of renal cell carcinoma (RCC). We investigated the expression of plakoglobin (a component of the cadherin-catenin adhesion system) in 94 samples of normal kidney tissue from patients with RCC, in 109 primary renal cell carcinomas and in 16 metastases by immunohistochemistry. Expression of plakoglobin was significantly diminished in tumor tissue, particularly in metastatic lesions, as compared to normal kidney tissue (p < 0.001). Follow-up data were available from 87 patients. Patients with a diffuse plakoglobin expression (91-100% positive cells) in primary tumor tissue had a significant better survival rate than patients with a disturbed plakoglobin expression (p < 0.05) as determined by the log rank test. These results indicate that loss of plakoglobin may play an important role in malignant transformation of renal cells. Plakoglobin expression status could give additional information about the individual prognosis.
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PMID:Expression of plakoglobin in renal cell carcinoma. 989 72

Loss of E-cadherin and catenin expression may be associated with distant and lymph node metastases in breast cancer. Heterogeneity of E-cadherin expression is associated with poor prognosis, suggesting that E-cadherin and catenins may serve as useful prognostic markers for invasive breast carcinoma. Reduction or loss of expression of either E-cadherin or catenins is associated with invasion, metastasis and poor prognosis in several types of human malignancies. We investigated the expression of E-cadherin, and alpha- and beta-catenins by immunohistochemistry in 171 cases of primary invasive breast cancer, and compared the expression with clinicopathological parameters to define the relationship between expression and prognosis. E-cadherin immunoreactive protein was shown to be expressed in 97 cases. Reduction or lack of expression of E-cadherin was associated with distant metastasis. Based on immunohistochemical heterogeneity, E-cadherin-positive tumors were classified into heterogeneous, homogeneous and intermediate types. Interestingly, although patients with heterogeneous type demonstrated the lowest incidence of distant metastasis at diagnosis, they showed a higher incidence of subsequent distant metastasis, after surgery, and a lower survival rate than those with homogeneous type (p<0.05). E-cadherin expression was reduced or negative in metastatic axillary lymph nodes regardless of the expression in the primary tumor, suggesting that changes in E-cadherin expression are associated with not only distant metastasis but also lymph node metastasis. Tumors negative for either alpha- or beta-catenin expression demonstrated a higher incidence of distant metastasis than those expressing both catenins, suggesting that the expression of catenins is involved in breast cancer metastasis. Reduction or loss of E-cadherin and catenin expression may be associated with distant and lymph node metastases in invasive breast cancer, and the heterogeneous type may be associated with poor prognosis.
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PMID:The loss of E-cadherin, alpha- and beta-catenin expression is associated with metastasis and poor prognosis in invasive breast cancer. 1117 80

Src has been implicated in the development and progression of human colon cancer. Because the capacity for tumor cells to dissociate from the primary tumor is a critical step in the development of metastases, the effect of a naturally occurring, activated Src-531 on intercellular adhesion was examined. Homotypic adhesion was assessed using dissociation assays on Src-transformed rat fibroblasts and human colon cancer cell lines. The data indicate that both rodent and human cells expressing the mutant Src protein display up to 7-fold less homotypic adhesion than do wild-type cells (P < 0.01). Experiments demonstrated that cadherin was phosphorylated in cells transfected with activated Src and that cadherin/catenin complexes were disrupted as a result. Experiments using dominant negative (DN) Src or an Src-specific inhibitor (PD 180970), demonstrated that adhesion was restored when Src activity was inhibited in Src-531 transfectants, confirming that Src is a causal factor in the decreased homotypic adhesion observed. In addition, DN Ras, DN focal adhesion kinase (FAK), but not Stat3beta, restored intercellular adhesion, which suggested that Ras and FAK may be downstream effectors of Src-mediated homotypic adhesion. Collectively, these data support a role for Src, Ras, and FAK in the regulation of intercellular adhesion, which may in turn regulate metastatic potential of human colon cancer cells.
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PMID:Increased Src activity disrupts cadherin/catenin-mediated homotypic adhesion in human colon cancer and transformed rodent cells. 1198 Jun 66

Inflammatory breast carcinoma (IBC) is characterized by florid tumor emboli within lymphovascular spaces termed lymphovascular invasion (LVI). Using a human-scid model of IBC (MARY-X), we have demonstrated using retrovirally-mediated dominant-negative E-cadherin mutant approaches (H-2K(d)-E-cad), that the tumor cell embolus (IBC spheroid) forms on the basis of an intact and overexpressed E-cadherin/alpha, beta-catenin axis which mediates tumor cell-tumor cell adhesion analogous to the embryonic blastocyst and accounts for the compactness of the embolus. The tumor cell embolus (IBC spheroid), in contrast, fails to bind the surrounding vascular endothelial cells both in vitro and in vivo because of markedly decreased sialyl-Lewis X/A carbohydrate ligand-binding epitopes on its overexpressed MUC1 which are necessary for binding endothelial cell E-selectin. This tumor cell-endothelial cell aversion further contributes to the compactness of the IBC spheroid and its passivity in metastasis dissemination. This passivity is manifested by a dramatic increase in metastatic pulmonary emboli following palpation of the primary tumor. In assessing this passivity of metastatic dissemination, we compared the effects of palpation on MARY-X with the effects of palpation on a derived dominant-negative E-cadherin mutant (H-2K(d)-E-cad), as well as other well known human tumoral xenografts exhibiting no (MCF-7, T47D), low (MDA-MB-231, MDA-MB-468) or high (C8161, M24(met)) levels of spontaneous metastasis but no LVI. Palpation of each xenograft similarly increased intratumoral pressure by 200% (10-->30 mmHg) but dramatically increased the numbers and sizes of pulmonary metastases 10-100-fold (P<0.001) only in MARY-X. The mechanism of this effect was through an immediate post-palpation release of circulating tumor emboli detected 2-3 min after palpation (P<0.01) by human cytokeratin 19 RT-PCR of extracted RNA from 300 microl of murine blood. Although circulating human tumor cell-derived growth factors (IGF-I, IGF-II, TGF-alpha and TGF-beta) and angiogenic factors (VEGF and bFGF) were detected by ELISA in murine serum of MARY-X, palpation did not further increase the circulating levels of these factors (P>0.1). Our findings support the cooperative role of E-cadherin and sialyl-Lewis X/A-deficient MUC1 in the passive dissemination of tumor emboli in IBC.
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PMID:Cooperative role of E-cadherin and sialyl-Lewis X/A-deficient MUC1 in the passive dissemination of tumor emboli in inflammatory breast carcinoma. 1203 65

The cadherin-catenin complex has been recognized as an important factor associated with tumor metastasis. However, the clinical significance of the expression of adhesion molecules in lymph nodes with metastasis remains unclear. The aim of this study was to investigate the clinical significance of the re-expression of the cadherin-catenin complex in metastatic lymph nodes in patients with advanced gastric cancer. Immunohistochemical expression of E-cadherin, alpha- and beta-catenin were analyzed in 96 primary gastric cancers with serosal invasion and in 79 lymph nodes with metastasis. The expression levels of these adhesion molecules in primary tumors and lymph nodes with metastasis were compared. Ninety-four out of 96 primary tumors (98%) showed reduced expression of adhesion molecules. Out of 79 cases with lymph node metastasis, increased expression of one or more adhesion molecules in metastatic foci as compared with primary tumors was detected in 52 cases (66%). Re-expression of adhesion molecules in metastatic lymph nodes was detected in a more advanced stage. The overall 5-year survival rate of the 52 patients who had lymph nodes with metastasis with re-expression of adhesion molecules (8%) was significantly poorer than that of the 27 who had lymph nodes with metastasis without re-expression of adhesion molecules (33%, P = 0.0012). The re-expression of the cadherin-catenin complex in lymph nodes with metastasis may play an important role in the growth of cancer cells in metastatic foci. A comparison of the expression patterns of adhesion molecules between the primary tumor and metastatic lymph nodes may provide new prognostic information for patients with advanced gastric cancer.
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PMID:Re-expression of the cadherin-catenin complex in lymph nodes with metastasis in advanced gastric cancer: the relationship with patient survival. 1207 32

The E-cadherin/catenin cell adhesion system is often down-regulated in epithelial tumors. This is thought to play an important role in cancer invasion and metastasis, and restoration of this system may suppress metastatic spread of cancer. In this study, the effects of a Ras farnesylation inhibitor (FTI-277) on E-cadherin-mediated cell-cell adhesion and metastatic potential were examined. In cell aggregation assays, FTI-277 stimulated aggregation of colon, liver and breast cancer cells. In vitro cultures of cancer cells showed that FTI-277 induced strong cell-cell contact. Immunoblotting analysis showed that FTI-277 increased E-cadherin/catenin (alpha, beta and gamma) expression and strongly stabilized E-cadherin/catenin with the actin cytoskeleton. Northern blotting studies indicated that the observed increase in the E-cadherin/catenin protein content was due to increased expression of their genes. After inoculation of the spleens of mice with severe combined immunodeficiency (SCID) with cancer cells, FTI-277 treatment for 3 weeks markedly reduced splenic primary tumor growth and the rate of liver metastasis compared with control counterparts. Our data demonstrate that FTI-277 can activate functioning of the E-cadherin-mediated cell adhesion system, which is associated with suppression of cancer cell metastasis. Therefore, selective inhibition of Ras activation may be useful for preventing cancer metastasis.
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PMID:Ras farnesylation inhibitor FTI-277 restores the E-cadherin/catenin cell adhesion system in human cancer cells and reduces cancer metastasis. 1235 56

Cadherin-mediated adhesion plays an important role in maintaining cell-cell contacts and reducing tumor metastasis. However, neo-expression of E-cadherin in ovarian carcinoma does not prevent the release and spread of cells from the primary tumor. Because caveolin-1 is down-regulated concomitantly with E-cad expression, we investigated whether the stability of adherens junctions in ovarian carcinoma was affected by caveolin-1 expression. We used IGROV1 cells transfected with caveolin-1 (IGtC3), mock-transfected control cells (IGtM87), and SKOV3 cells that endogenously express caveolin-1. Simultaneous expression of caveolin-1 and E-cadherin favored membrane distribution of E-cadherin and its associated catenin (p120ctn), even when caveolin-1 was only focally associated with adherens junctions. Silencing of caveolin-1 induced intracellular E-cadherin redistribution in IGtC3 and SKOV3 cells. Treatment with the specific src kinase inhibitor PP1 increased E-cadherin expression in IGtM87 and SKOV3 cells and enhanced membrane localization of both E-cadherin and p120ctn. However, PP1 could not completely reverse the detrimental effects on cell-cell adhesion induced by Ca2+ depletion in IGtM87 cells. Together, our data suggest that caveolin-1 expression indirectly promotes cell-cell adhesion in ovarian carcinoma cells by a mechanism involving inhibition of src-related kinases. Thus, down-regulation or loss of caveolin-1 might contribute significantly to the spread of tumor cells from the primary tumor.
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PMID:Simultaneous expression of caveolin-1 and E-cadherin in ovarian carcinoma cells stabilizes adherens junctions through inhibition of src-related kinases. 1625 25

The interaction between tumor cells and the microenvironment has substantial effects on tumor cell behavior by influencing cell-cell as well as cell-matrix contacts. The underlying molecular mechanisms are only partially unraveled. In this review we focus on the influence of the stromal microenvironment, especially collagen type I and type III on cellular adhesion and epithelial to mesenchymal transition (EMT). Extensive studies have emphasized that components of the microenvironment such as fibrillar collagen or growth factors like transforming growth factor beta are involved in induction of dedifferentiation of epithelial cells accompanied by disruption of the E-cadherin adhesion complex and reduced E-cadherin concentrations. On the molecular level many different proteins have been identified which are involved in the regulation of EMT, such as activation of integrins, intracellular kinases such as Src, focal adhesion kinase (FAK) or phosphatidylinositol-3 kinase (PI3-kinase) and alteration of catenin phosphorylation. The reduced cellular adhesion influences the tissue integrity and allows tumor cells to disseminate from the primary tumor representing an early step in cancer metastasis.
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PMID:Microenvironmental regulation of E-cadherin-mediated adherens junctions. 1850 91

Despite recent advances in molecular biology that have clarified the mechanisms involved in the metastasis of several types of cancer, the molecular mechanism underlying the metastasis of renal cell carcinoma (RCC) remains unclear. Two RCC cell lines were successfully established from the surgical specimens of a matched primary tumor and adrenal metastasis from the same RCC patient, and were designated as TMK-1P and TMK-1M, respectively. Extensive characterization was accomplished using various methods, including the Matrigel invasion assay, DNA microarray analysis and real-time reverse transcriptase (RT)-polymerase chain reaction (PCR). While TMK-1P grew faster than TMK-1M, the invasive ability of TMK-1M was higher than that of TMK-1P. DNA microarray analysis showed a large differential expression of genes related to cell adhesion and the extracellular matrix molecules of which hexabrachion (tenascin-C), epidermal growth factor receptor, cadherin-6, and beta1-catenin were down-regulated, and the 67 kDa laminin receptor 1 and transforming growth factor-beta-induced 68 kDa protein (betaig-h3) were up-regulated in TMK-1M. Real-time RT-PCR analysis confirmed this differential gene expression between the two cell lines. The RCC cell lines may be useful in studying tumor invasion and screening markers for metastasis.
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PMID:Characterization and gene expression analysis of novel matched primary and metastatic renal cell carcinoma cell lines. 1869 98


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