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Query: UMLS:C0001511 (Adhesion)
 5,955 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Integrins play an important role in tumour progression by influencing cellular responses and matrix-dependent adhesion. However, the regulation of matrix-dependent adhesion assembly in epithelial cells is poorly understood. We have investigated the integrin and signalling requirements of cell-matrix adhesion assembly in colon carcinoma cells after plating on fibronectin. Adhesion assembly in these, and in the adenoma cells from which they were derived, was largely dependent on alpha v beta 6 integrin and required phosphorylation of FAK on tyrosine-397. The rate of fibronectin-induced adhesion assembly and the expression of both alpha v beta 6 integrin and FAK were increased during the adenoma-to-carcinoma transition. The matrix-dependent adhesion assembly process, particularly the final stages of complex protrusion that is required for optimal cell spreading, required the activity of extracellular signal-regulated kinase (ERK). Furthermore, phosphorylated ERK was targeted to newly forming cell--matrix adhesions in the carcinoma cells but not the adenoma cells, and inhibition of FAK--tyrosine-397 phosphorylation or MEK suppressed the appearance of phosphorylated ERK at peripheral sites. In addition, inhibition of MEK--ERK activation blocked the formation of peripheral actin microspikes that were necessary for the protrusive phase of cell-matrix adhesion assembly. Thus, MEK--ERK--dependent peripheral actin re-organization is required for the full development of integrin-induced adhesions and this pathway is stimulated in an in vitro model of colon cancer progression.
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PMID:The protrusive phase and full development of integrin-dependent adhesions in colon epithelial cells require FAK- and ERK-mediated actin spike formation: deregulation in cancer cells. 1149 15

Adhesion molecules are intimately involved in the process of tumour progression. Among them, E-selectin is an inducible endothelial cell adhesion molecule that plays a role in the interactions of neoplastic cells with the endothelium. These interactions are required for the trans-endothelial migration of tumour cells that leads to the growth at the new sites. Since the detailed events in the early phase of metastasis still remain poorly defined, our study has undertaken an electron-microscopic analysis of the interactions of human colon carcinoma cells with endothelial cells as well as an analysis of the effect of recombinant purified E-selectin in the cell signalling involved in colon cancer cell malignant phenotype. Results revealed that SW480 and T84 colon cancer cell lines show different features, different adhesion kinetics, a different cytoskeletal organization, and a different tyrosine phosphorylation pattern when seeded on an endothelial cell monolayer or recombinant E-selectin. In particular T84 cancer cells adhere more efficiently to the E-selectin and this interaction is associated with pronounced morphological changes, actin redistribution and filopodial processes, and an increase in tyrosine phosphorylation of different proteins. These data support the hypothesis that E-selectin ligand is not only a cell-cell adhesion molecule but also initiates a signalling transduction pathway inside the cells.
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PMID:Different phenotypes of colon carcinoma cells interacting with endothelial cells: role of E-selectin and ultrastructural data. 1268 69

Colon cancer preferentially metastasizes to the liver. To determine cellular backgrounds of this preference, we generated an enhanced green fluorescent protein (eGFP)-expressing rat adenocarcinoma cell line (CC531s) that forms metastases in rat liver after administration to the portal vein. Intravital videomicroscopy (IVVM) was used to visualize early events in the development of tumors in livers of live animals from the time of injection of the cancer cells up to 4 days afterward. Based on information obtained with IVVM, tissue areas were selected for further analysis using confocal laser scanning microscopy (CLSM), electron microscopy (EM), and electron tomography. It was shown that initial arrest of colon cancer cells in sinusoids of the liver was due to size restriction. Adhesion of cancer cells to endothelial cells was never found. Instead, endothelial cells retracted rapidly and interactions were observed only between cancer cells and hepatocytes. Tumors developed exclusively intravascularly during the first 4 days. In conclusion, initial steps in the classic metastatic cascade such as adhesion to endothelium and extravasation are not essential for colon cancer metastasis in liver.
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PMID:Visualization of early events in tumor formation of eGFP-transfected rat colon cancer cells in liver. 1457 75

Adhesion molecules play an important role in tumor metastasis. E-selectin can support adhesion of colon cancer cells through the recognition of specific carbohydrate ligands. High levels of soluble E-selectin (sE-selectin) had been reported in melanoma and some epithelial tumors, especially in colorectal carcinoma. The concentrations of the sE-selectin were investigated in serum samples of 64 patients (32 men and 32 women) with colorectal cancer and 16 healthy subjects. Median age was 57 (range 20-75). Nineteen patients were staged as Dukes D, 9 of whom had liver metastasis. Serum levels of sE-selectin were determined by ELISA. In the study group, sE-selectin concentrations (mean+/-SE, ng/ml) were not significantly elevated, compared with the control group (41.09+/-4.57 in the control group and 43.80+/-1.88 in patients, p>0.05). Mean sE-selectin levels were 42.27+/-1.85 in non-metastatic and 47.42+/-4.57 in metastatic patients (p>0.05). Serum concentrations of sE-selectin were significantly elevated in patients with colorectal cancer metastatic to liver (59.07+/-7.52) in comparison to other patients without liver metastasis (p=0.013). There were no significant correlations between sE-selectin levels and other parameters such as age of patients, stage of disease, histopathological differentiation or localization of primary tumor. Elevated sE-selectin levels were confirmed as correlating with poor overall survival. In conclusion, sE-selectin concentrations may not be used as a predictive marker of metastasis in colorectal carcinoma, but high levels of sE-selectin may support diagnosis of liver metastasis.
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PMID:Serum levels of soluble E-selectin in colorectal cancer. 1525 58

Adhesion receptors play crucial roles in the neoplastic transformation of normal cells through induction of cancer-specific cellular behaviour and morphology. This implies that cancer cells likely express and utilize a distinct set of adhesion receptors during carcinogenesis. Colon cancer is an excellent model system for the study of this process, since both molecular genetic and morphological changes have been well established for this disease. We recently reported increased expression of the cell surface adhesion receptor, syndecan-2, in several colon carcinoma cell lines. Indeed, increased syndecan-2 expression was necessary for tumourigenic activity, suggesting that syndecan-2 might have value as both a new diagnostic marker and a possible therapeutic target. Here, we review recent advances in understanding the role of syndecan-2 in the carcinogenesis of colon cells, and discuss a leading role for this molecule in a new era for colon cancer treatment.
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PMID:New insights into syndecan-2 expression and tumourigenic activity in colon carcinoma cells. 1533 51

The purpose of this study is to assess the effects of anti-inflammatory on activation of nuclear factor-kappaB and mRNA and protein expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in intestinal mucosal biopsy specimens from patients with ulcerative colitis (UC). A total of 27 cases with UC were investigated. 15 cases received sulfasalazine (SASP) treatment or SASP and glucocorticoid treatment, 12 cases did not receive any medication related with UC. Normal mucosa from 9 colon cancer cases served as control. Ten pieces of intestinal mucosal biopsy specimens were obtained from each patient. The mRNA expression of ICAM-1 and VCAM-1 were determined by reversal transcription-polymerase chain reaction (RT-PCR). The protein levels of ICAM-1 and VCAM-1 were measured by enzyme linked immunosorbent assay (ELISA). NF-kappaB DNA binding activity was evaluated by electrophoretic mobility shift assay (EMSA). The results showed that NF-kappaB DNA binding activity, mRNA and protein expression of ICAM-1 and VCAM-1 were increased significantly in patients with UC, compared with normal control (P<0.05). Glucocorticoids and SASP markedly inhibited NF-kappaB activation and significantly decreased mRNA and protein expression of ICAM-1 and VCAM-1 (P<0.05). Adhesion molecules (ICAM-1 and VCAM-1) gene activation had significant positive correlation with the NF-kappaB DNA binding activity (r=0.8652 P<0.05, r=0.7902, P<0.05, respectively). We concluded that NF-kappaB is a major and essential factor in regulating the expression of adhesion molecules, it plays an important role in the pathogenesis of UC. SASP and glucocorticoids ameliorate UC via inhibition of NF-kappaB activation and reduction of adhesion molecules expression.
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PMID:[The effects of anti-inflammatory on activation of nuclear factor-kappaB and expression of cell adhesion molecules in patients with ulcerative colitis]. 1555 46

Inflammatory bowel diseases (IBD) are linked to an increased risk of developing colon cancer, by inflammatory mediators and alterations to the extracellular matrix (ECM). The events induced by inflammatory mediators lead to dysregulated activation and induction of inflammatory genes such as cyclooxygenase-2 (COX-2). COX-2 is involved in the conversion of arachidonic acid to biologically active prostanoids and is highly upregulated in colon cancer. Since inflammation-induced changes to the extracellular matrix could affect integrin activities, we here investigated the effect of integrin signalling on the level of COX-2 expression in the non-transformed intestinal epithelial cell lines, Int 407 and IEC-6. Adhesion of these cells to a collagen I- or IV-coated surface, increased surface expression of alpha2beta1 integrin. Activation of integrins with collagen caused an increased cox-2 promoter activity, with a subsequent increase in COX-2 expression. The signalling cascade leading to this increased expression and promoter activity of cox-2, involves PKCalpha, the small GTPase Ras and NFkappaB but not Erk1/2 or Src activity. The integrin-induced increase in cellular COX-2 activity is responsible for an elevated generation of reactive oxygen species (ROS) and increased cell migration. This signalling pathway suggests a mechanism whereby inflammation-induced modulations of the ECM, can promote cancer transformation in the intestinal epithelial cells.
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PMID:Alpha2beta1 integrin signalling enhances cyclooxygenase-2 expression in intestinal epithelial cells. 1697 45

Matrix metalloproteinases (MMPs), in particular MMP-2 and MMP-9, are involved in colon cancer progression and metastasis due to their ability to degrade extracellular matrix (ECM) components. In previous studies we described the MMP-9 hemopexin like domain (MMP-9-PEX) as an MMP-9 antagonist. In the present study it was examined whether recombinant MMP-9-PEX has an inhibitory effect on migration and adhesion of colorectal carcinoma cells. Furthermore, we searched for MMP-9 substrate binding sites within the MMP-9-PEX by surface plasmon resonance. Migration of SW620 and LS174 cells was investigated in a modified Boyden chamber assay. In the presence of 0.2 microg/ml MMP-9-PEX migration of SW620 was decreased by 34%, while addition of 0.4 microg/ml diminished migration by 56%. Migration of LS174 cells was not affected by MMP-9-PEX. Adhesion studies were performed on 96-well plates coated with gelatin, collagen type I, and laminin, respectively. In the presence of MMP-9-PEX, adhesion of SW620 cells to these coating substrates was significantly inhibited. Surface plasmon resonance studies revealed binding of collagen type I and IV, elastin, and fibrinogen to proMMP-9 as well as to MMP-9-PEX. However, equilibrium constants (Kd) indicated a higher affinity of proMMP-9 to the matrix proteins. This could indicate that there is more than one binding site for matrix components within the entire proMMP-9 molecule. Since migration and adhesion of metastatic colorectal carcinoma cells were reduced by MMP-9-PEX, this recombinant MMP-9 antagonist might be of therapeutical interest.
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PMID:MMP-9-hemopexin domain hampers adhesion and migration of colorectal cancer cells. 1733 39

Adhesion of cancer cells to endothelium is considered an essential step in metastasis. However, we have shown in a previous study that when rat colon cancer cells are administered to the vena portae, they get stuck mechanically in liver sinusoids. Then, endothelial cells retract rapidly and cancer cells bind to hepatocytes. We investigated the molecular nature of these interactions between colon cancer cells and hepatocytes. Cancer cells in coculture with hepatocytes became rapidly activated with distinct morphological changes. Cancer cells formed long cytoplasmic protrusions towards hepatocytes in their close vicinity and these protrusions attached to microvilli of hepatocytes. Then, adhering membrane areas were formed by both cell types. Integrin subunits alphav, alpha6 and beta1 but not alphaL, beta2, beta3 and CD44 and CD44v6 were expressed on the cancer cells. In conclusion, colon cancer cells show an active behaviour to bind to hepatocytes, likely involving the integrin subunits alphav, alpha6 and beta1, indicating that early events in colon cancer metastasis in liver are distinctly different than assumed thus far.
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PMID:Interactions between colon cancer cells and hepatocytes in rats in relation to metastasis. 1820 63

Iatrogenic tumor cell implantation within surgical wounds can compromise curative cancer surgery. Adhesion of cancer cells, in particular colon cancer cells, is stimulated by exposure to increased extracellular pressure through a cytoskeleton-dependent signaling mechanism requiring FAK, Src, Akt, and paxillin. Mechanical stimuli during tumor resection may therefore negatively impact patient outcome. We hypothesized that perioperative administration of colchicine, which prevents microtubule polymerization, could disrupt pressure-stimulated tumor cell adhesion to surgical wounds and enhance tumor-free survival. Ex vivo treatment of Co26 and Co51 colon cancer cells with colchicine inhibited pressure-stimulated cell adhesion to murine surgical wounds and blocked pressure-induced FAK and Akt phosphorylation. Surgical wound contamination with pressure-activated Co26 and Co51 cells significantly reduced tumor-free survival compared with contamination with tumor cells under ambient pressure. Mice treated with pressure-activated Co26 and Co51 cells from tumors preoperatively treated with colchicine in vivo displayed reduced surgical site implantation and significantly increased tumor-free survival compared with mice exposed to pressure-activated cells from tumors not pretreated with colchicine. Our data suggest that pressure activation of malignant cells promotes tumor development and impairs tumor-free survival and that perioperative colchicine administration or similar interventions may inhibit this effect.
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PMID:Colchicine inhibits pressure-induced tumor cell implantation within surgical wounds and enhances tumor-free survival in mice. 1870 96


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