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)

Reductions in cell-cell adhesion and stromal and vascular invasion are essential steps in the progression from localized malignancy to metastatic disease. In this study, changes in the expression of the components of the E-cadherin-catenin cell adhesion complex have been investigated using immunohistochemical techniques in primary tumours and nodal metastases from 36 patients with squamous cell carcinoma of the head and neck. For 14 patients the corresponding primary and nodal metastases samples were available. None of the 51 samples showed normal E-cadherin expression when compared with either the adjacent normal squamous epithelium or with normal colonic epithelium that was used as positive control material. In 88% of primary tumours fewer than 50% of cells exhibited normal membranous E-cadherin expression. Loss of membranous E-cadherin expression was more extensive in poorly differentiated carcinomas while, in individual carcinomas, membranous E-cadherin expression was stronger in those parts of the neoplasm that expressed the differentiation marker involucrin. Expression of beta-catenin generally paralleled that of E-cadherin, but in 12 cases there was strong membranous beta-catenin expression in samples that exhibited predominantly cytoplasmic E-cadherin labelling. Expression of alpha-catenin was generally weak and did not correlate with the expression of either beta-catenin or E-cadherin. Marked intratumoral heterogeneity for protein expression was evident for all antibodies, and the abnormal expression of the catenins is a novel finding. E-cadherin is expressed more intensely in cells with greater squamous differentiation, but there was no correlation between the decreased expression of any of the adhesion molecules of the E-cadherin complex tested and local recurrence, metastasis or survival. The loss of expression of components of the E-cadherin complex is a common abnormality in squamous carcinomas and, while it may be permissive for metastasis, it does not appear to be the only determinant of this process.
Br J Cancer 1997
PMID:Expression of the E-cadherin-catenin cell adhesion complex in primary squamous cell carcinomas of the head and neck and their nodal metastases. 916 40

The E2F group of transcription factors transactivates genes that promote progression through the G1-S transition of the cell cycle. Members of the retinoblastoma (Rb) family of proteins bind to E2Fs and inhibit this function. E2F-4, one example of the E2F group, functions as an oncogene when transfected into nontransformed cells in vitro. On the other hand, mice that are homozygously lacking a normal E2F-1 gene develop cancers, consistent with a tumor-suppressive role for this gene. The exact function of E2Fs has thus been unclear; moreover, direct involvement of this gene in primary human tumorigenesis has not been shown. We, therefore, investigated mutation within the E2F-4 coding region in 16 primary gastric adenocarcinomas, 12 ulcerative colitis-associated neoplasms, 46 sporadic colorectal carcinomas, 9 endometrial cancers, and 3 prostatic carcinomas. We limited our investigation to the serine repeat within E2F-4, reasoning that this tract might be altered in genetically unstable tumors (replication error-positive, or RER+). All tumors were RER+, with the exception of a control group of 15 RER- sporadic colorectal carcinomas. PCR with incorporation of [32P]dCTP was performed using primers flanking the serine trinucleotide (AGC) repeat. Twenty-two of 59 gastrointestinal tumors (37%) contained E2F-4 mutations; these comprised 5 of 16 gastric tumors (31%), 4 of 12 ulcerative colitis-associated neoplasms (33%, including 1 dysplastic lesion), and 13 of 31 sporadic colorectal cancers (42%). No mutation was present in any of the endometrial, prostate, or RER- colorectal tumors. Of note, homozygous mutations occurred in three cases, and two of seven informative patients showed loss of one E2F-4 allele in their tumors. Furthermore, the RER+ sporadic colorectal tumors were evaluated at trinucleotide repeats within the genes for N-cadherin and B-catenin; no tumors demonstrated mutation of these genes. These data suggest that E2F-4 is a target of defective DNA repair in these tumors.
Cancer Res 1997 Jun 15
PMID:Frequent mutation of the E2F-4 cell cycle gene in primary human gastrointestinal tumors. 919 6

There are three macroscopic types of hepatic bile duct carcinoma, such as papillary (P-), nodular (N-) and diffuse (D-) type. Immunohistochemical studies demonstrated that P-type expressed cadherin and catenin higher than N- and D-types. The expressions of both cadherin and catenin were found stronger in pap and tub1 than tub2. The nuclear area of cancer cell, correlated with both labeling index of Ki-67 and aberrant accumulation of p53, was significantly larger in the subserosal layer than in the mucosal layer. These may explain the differences in the biological behavior between P- and N, D-types. P-type grows within the mucosal layer, while N- and d-type are more invasive, developing into the subserosal layer. Our clinical data also demonstrates the poor prognosis of N-, D-type of hepatic bile duct carcinoma. On these basis of the biological malignancy of N, D-type, it is critical to remain the surgical margin free from cancer cells to cure this type of hepatic bile duct carcinoma.
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PMID:[Mode of spreading and biological behavior in bile duct carcinoma]. 921 11

Previous in vitro and in vivo model studies have shown that when E-cadherin expression in carcinoma cells is reduced, invasive behaviour ensues. The situation in human cancer in vivo, however, appears to be more complex, as immunohistochemically determined E-cadherin expression in various carcinomas, including colorectal cancer, does not always correlate with invasive growth. Loss of cell adhesion during invasion in spite of E-cadherin expression might be associated with a defective cadherin-catenin complex. The expression of alpha- and beta-catenin in comparison with E-cadherin was therefore examined in colorectal adenomas and carcinomas and in lymph node and liver metastases. In normal colonic mucosa, alpha- and beta-catenin immunoreactivity occurred along the lateral plasma membranes of the epithelial cells, in a pattern identical to E-cadherin staining. A similar pattern was found in colorectal adenomas and in most malignancies. In general, in neoplastic epithelia, the majority of the cancer cells displayed a normal (matching) pattern of E-cadherin and catenin expression. It is concluded that the patterns of expression of E-cadherin and alpha- and beta-catenin are very similar in colorectal neoplasms. This observation indicates that invasion in colorectal cancer is not paralleled by consistent loss of expression of the components of the cadherin-catenin complex.
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PMID:Patterns of alpha- and beta-catenin and E-cadherin expression in colorectal adenomas and carcinomas. 934 36

During the progression of many cancers, cell-cell adhesion molecules, e.g., E-cadherin (EC), may be down-regulated. In a number of carcinomas, EC has been described as an independent prognostic variable. We have studied the expression of adhesion molecules participating in cadherin-catenin complexes in renal cell carcinoma (RCC) specimens. Expression of EC, catenins and p120cas protein was examined in frozen tissue of 90 RCC specimens by immunohistochemistry, and these molecules were evaluated for their significance as prognostic markers. Staining was scored as normal (homogeneously positive at cell-cell borders) or abnormal (heterogeneous or absent). A significant correlation between poor survival and decreased expression of alpha-, beta- or gamma-catenin was observed, whereas no association between survival and EC or p120cas expression was seen. Cox's proportional hazard regression analysis showed that in patients with pT1-3N0M0 disease, reduced alpha-catenin expression correlated with poor survival, suggesting that alpha-catenin expression might be an independent prognostic indicator for patients of this group.
Int J Cancer 1997 Oct 21
PMID:Decreased expression of alpha-catenin is associated with poor prognosis of patients with localized renal cell carcinoma. 935 75

Cell-cell adhesion mediated by E-cadherin is often lost or disturbed in human carcinomas. For regular adhesive function, E-cadherin has to form complexes with peripheral cytoplasmic catenins which are multifunctional proteins that are also involved in signal transduction and growth regulation. We have analyzed the expression levels of the genes encoding alpha-catenin, beta-catenin and plakoglobin in correlation to the E-cadherin expression levels in cell lines derived from human cervical carcinomas. Reduced mRNA and protein levels were detected for plakoglobin, whereas alpha- and beta-catenin showed only reduced protein (but not mRNA) levels. The alterations in catenin gene expression were often associated with absent or reduced E-cadherin. The findings indicate that a reduction of catenin gene expression may contribute to the development of cervical carcinomas.
Cancer Lett 1997 Dec 09
PMID:Reduced gene expression of E-cadherin and associated catenins in human cervical carcinoma cell lines. 946 Oct 36

Angiogenesis plays an important role in various diseases and conditions such as malignant tumor, wound healing, and atherosclerosis. Since cell-to-cell adhesion may play a key role in angiogenesis, we investigated the effect of the cadherin-catenin-cytoskeleton complex on angiogenesis in human umbilical vein endothelial cells (HUVECs). Immunofluorescence staining revealed that alpha-catenin, beta-catenin, and plakoglobin were concentrated at cell-cell contacts in HUVECs. Antisense oligonucleotide (AS-oligo), complementary to the region of human plakoglobin was dissolved in saline and applied to the media at 1 mM every 12 h for 4 days, and sense oligonucleotide (S-oligo) was used as control. HUVEC migration from an injury line was enhanced by AS-oligo. Interestingly, HUVECs migrated in line with S-oligo, and in a scattered fashion with AS-oligo. Tube formation on Matrigel occurred earlier with AS-oligo than with S-oligo. These findings indicate that plakoglobin inhibited HUVEC migration and tube formation (angiogenesis) by regulating cell-cell adhesion.
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PMID:The role of cadherin-catenin-cytoskeleton complex in angiogenesis: antisense oligonucleotide of plakoglobin promotes angiogenesis in vitro, and protein kinase C (PKC) enhances angiogenesis through the plakoglobin signaling pathway. 947 58

Cancer is a chronic and progressive disease characterised by disturbances of growth, cellular differentiation and maintenance of tissue integrity. The latter phenomenon leads to invasion. The transition from the noninvasive towards the invasive stage of the disease is crucial because it transforms a benign and easily curable lesion into a malignant and therapy-resistant disease. Tumour progression is the result of a number of genetic alterations, initiated by a single mutation without immediate clinical manifestations and ending with a metastatic cascade. Activation of tumour-promoter genes (oncogenes), by mutation or overexpression, and inactivation of tumour-suppressor genes, by mutation or deletion, favour oncogenesis. Separate genes are implicated in distinct steps of the tumour progression. Defects in DNA-repair genes influence all steps. Metastasis is a multistep process of invasion. At each step invasion occurs within a micro-ecosystem in which a continuous molecular crosstalk takes place between the cancer cells and the host cells that participate at the establishment of the tumour. The cancer cells carry the genetic alterations and act as the founders of the micro-ecosystem. We shall discuss the invasion-suppressor function of the E-cadherin/catenin complex. Inactivation of one element of this complex may initiate invasion in an appropriate genetic background. Such inactivation may take place at various levels: mutation in coding sequences; hypermethylation of the promoter; mRNA instability; tyrosine phosphorylation; proteolysis; extracellular interactions.
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PMID:[Molecular mechanism of cancer seeding: adhesion molecules and signal transduction networks]. 949 Sep 22

Mutations of the beta-catenin gene (CTNNB1) have recently been implicated in the initiation of some colon carcinomas and melanomas. In these tumors, beta-catenin abnormally accumulates in the cell nuclei. In an ongoing immunohistochemical study of the cadherin-catenin complex protein expression in ovarian carcinomas, we observed beta-catenin in tumor cell nuclei in some cases; this prompted us to study whether or not this abnormal immunostaining pattern was due to mutation in the beta-catenin gene itself. This study examines beta-catenin immunohistochemical expression in 40 stage I and II ovarian borderline tumors and carcinomas of the most common histological types. Membrane expression was heterogeneous in all 40 cases. However, the cytoplasm and nucleus of five (one borderline tumor and four carcinomas) of the six endometrioid lesions contained beta-catenin expression. PCR and sequencing analyses of a 200-bp fragment of exon 3 of the CTNNB1 gene, encompassing the sequence for glycogen synthetase kinase-3beta phosphorylation, were performed in 11 tumors. Heterozygous substitution mutations at codon 37 in two cases (S37F and S37C) and at codon 41 in one case (T41A) were found in three endometrioid lesions (one borderline tumor and two carcinomas) with abnormal beta-catenin expression. Three endometrioid carcinomas and five tumors of other histological types analyzed showed normal DNA sequences. These results implicate beta-catenin gene mutations in ovarian malignant transformation with a characteristic phenotype: endometrioid ovarian carcinoma.
Cancer Res 1998 Apr 01
PMID:Mutations in the beta-catenin gene (CTNNB1) in endometrioid ovarian carcinomas. 953 26

E-cadherin is the major cell-cell adhesion molecule expressed by epithelial cells. Cadherins form a complex with three cytoplasmic proteins, alpha-, beta-, and gamma-catenin, and the interaction between them is crucial for anchoring the actin cytoskeleton to the intercellular adherens junctions. The invasive behavior of cancer cells has been attributed to a dysfunction of these molecules. In this study, we examined the distribution of the cadherin-catenin complex in a Chinese human thyroid cancer cell line, CGTH W-2, compared with that in normal human thyroid epithelial cells. In the normal cells, using immunofluorescence staining, E-cadherin and alpha-, beta-, and gammm-catenin were found to be localized at the intercellular junction and appeared as 135, 102, 90, and 80 kD proteins on Western blots. In CGTH W-2 cells, no E-cadherin and gamma-catenin immunoreactivity was detected by immunofluorescence or Western blotting; alpha- and beta-catenin were detected as 102 and 90 kD proteins on blots but gave a diffuse cytoplasmic immunofluorescence staining pattern in most cells, while beta-catenin was also distributed throughout the cytoplasm in most cells but was found at the cell junction in some, where it colocalized with alpha-actinin. The present data indicate that the loss of cell adhesiveness in these cancer cells may be due to incomplete assembly of the cadherin-catenin complex at the cell junction. However, this defect did not affect the linkage of actin bundles to vinculin-enriched intercellular junctions.
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PMID:Distribution of the cadherin-catenin complex in normal human thyroid epithelium and a thyroid carcinoma cell line. 970 70


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