Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The prognosis of patients with metastasised follicular thyroid carcinoma (FTC) is limited, necessitating the search for new treatment options. Beneficial effects of retinoids have been suggested in thyroid cancer and the present study was performed to investigate the effects of retinoic acid (RA) on important determinants of metastatic behaviour in FTC: the disengagement of tumour cells from the primary tumour and the degradation of extracellular matrix, focusing on the role of the plasmin activation system and the integrin and E-cadherin families of attachment molecules. Three FTC cell lines were studied: FTC-133, derived from the primary tumour; and FTC-236 and FTC-238, derived from metastases. FTC cell lines were cultured with 0.1, 1 and 10 microM 13-cis-RA or with the solvent DMSO for 1 and 5 days. Extracellular matrix degradation by these cell lines was studied by assessing the 48-h release of radioactivity from (35)S-methionine labelled extracellular matrix proteins synthesised by the MC3T3 cell line coated onto plastic. The involvement of constituents of the plasmin activation system was investigated by semi-quantitative RT-PCR and zymography. Attachment to extracellular matrix was studied by determining the number of adhering FTC cells to extracellular matrix coated onto plastic, 3 h after seeding. The involvement of attachment molecules was studied by RT-PCR with primers for integrin subclasses and E-cadherin and immunofluorescence for E-cadherin. Five days culturing with 10 microM RA reduced the degradation of extracellular matrix significantly in all cell lines: FTC-133 by 35%, FTC-236 by 74% and FTC-238 by 31%. Zymography revealed diminished activity of urokinase type plasminogen activator (uPA) in FTC-236 and FTC-238, but not in FTC-133 cultured with RA. mRNA expression of the uPA receptor was diminished in FTC-236. In the attachment assay, 10 microM RA for 5 days increased the number of adherent cells to extracellular matrix significantly by 91% in FTC-133, 64% in FTC-236 and 87% in FTC-238. No effects of RA on integrin or E-cadherin mRNA expression were observed. Immunofluorescence, however, revealed enhanced organisation of E-cadherin along the cell membrane by RA treatment. In conclusion, the present study demonstrates beneficial effects of RA on important determinants of metastatic behaviour in FTC cell lines, e.g. decreased degradation of extracellular matrix which may in part be explained by effects on the plasmin activation system and enhanced attachment to extracellular matrix. These findings may add to the explanations for beneficial effects of retinoids in thyroid cancer.
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PMID:Beneficial effects of retinoic acid on extracellular matrix degradation and attachment behaviour in follicular thyroid carcinoma cell lines. 1105 36

We established and characterized a new mammary tumor cell line, LM2, derived from M2 mammary adenocarcinoma which spontaneously appeared in a BALB/c female mouse. The LM2 cell line has been maintained in culture for more than 40 passages and grows as poorly differentiated elongated cells. Ultrastructural and immunocytochemistry analysis revealed characteristic features of adenocarcinoma. Cytogenetic studies showed that LM2 cells are fundamentally hypotetraploid. They express metalloproteinases (MMP) and show high levels of plasminogen activator type urokinase (uPA). They were sensitive to nitric oxide (NO)-mediated cytotoxicity when NO derived from an exogenous donor. In vivo, although LM2 cells were able to grow in the lungs, they could not metastasize to the same target organ from s.c. primary tumors. The LM2 mouse mammary adenocarcinoma cell line is a suitable model to examine different aspects of tumor biology, in particular those related to the different pathways involved in the metastatic cascade and in the cytotoxicity mediated by NO.
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PMID:Characterization of a fibroblastoid mammary carcinoma cell line (LM2) originated from a mouse adenocarcinoma. 1107 14

Several lines of evidence indicate that hepatocyte growth factor/scatter factor (HGF/SF) and its receptor, c-Met, may play an important role in progression of human glioma. In this study, effects of HGF/SF on urokinase- type plasminogen activator (uPA)-mediated proteolysis network were examined in c-Met-positive human glioma cell lines. Treatment of the glioma cells with various concentrations of HGF/SF resulted in an enhanced secretion of uPA proteins accompanying increased transcription of uPA mRNA in a dose dependent fashion. The levels of uPA receptor (uPAR) mRNAs were also elevated simultaneously upon HGF/SF stimulation, and the cell-surface associated uPA activity was also elevated by the treatment. Since concomitant expression of HGF and its receptor c-Met are frequently observed in malignant gliomas, these results suggest that HGF/SF participates in invasive process of malignant glioma cells not only by its motility-stimulating activity but also through enhanced degradation of the extracellular matrix induced by autocrine activation of uPA proteolysis network.
Clin Exp Metastasis 1999
PMID:Simultaneous up-regulation of urokinase-type plasminogen activator (uPA) and uPA receptor by hepatocyte growth factor/scatter factor in human glioma cells. 1108 86

Human tissue factor pathway inhibitor-2 (TFPI-2) is a Kunitz-type serine protease inhibitor that inhibits plasmin, trypsin, chymotrypsin, cathepsin G and plasma kallikrein but not urokinase (uPA) or tissue-type plasminogen activator and thrombin. Earlier studies from our and other laboratories have shown that the production of TFPI-2 is downregulated during the progression of various cancers. To investigate the role of TFPI-2 in the invasion and metastasis of lung tumors, the human lung cancer cell line A549, which produces high levels of TFPI-2, was stably transfected with a vector capable of expressing an antisense transcript complementary to the full-length TFPI-2 mRNA. Northern blot analysis was used to quantify the TFPI-2 mRNA transcript, and western blot analysis was used to measure TFPI-2 protein levels in parental cells and stably transfected (vector and antisense) clones. The levels of TFPI-2 mRNA and protein were significantly less in antisense clones than in the parental and vector controls. The invasive potential of the parental cells and stably transfected vector clones in vitro, as measured by the Matrigel invasion assay, was also markedly less than that of antisense clones. Further characterization of these clones showed that more cells migrated from antisense clones than from parental and vector clones. These data suggest that TFPI-2 is critical for the invasion and metastasis of lung cancer and that the downregulation of TFPI-2 production may be a feasible approach to increase invasiveness and metastasis.
Clin Exp Metastasis 2000
PMID:In vitro modulation of human lung cancer cell line invasiveness by antisense cDNA of tissue factor pathway inhibitor-2. 1131 97

Two types of gastric adenocarcinoma can be distinguished histopathologically: the diffuse and the intestinal type. Molecular pathology supports this theory by showing differences in the genetic pathways of both tumor types. In addition to known pathomorphological factors of prognosis, e.g., depth of tumor infiltration, number of lymph node metastases and resection margins, a few genes have been suggested to have prognostic impact in gastric carcinoma. Clinically relevant molecules whose expression or structure is altered include the plasminogen activator (uPA) and its inhibitor PAI-1 (plasminogen activator inhibitor type 1), the cell cycle regulator cyclin E, epidermal growth factor (EGF), the apoptosis inhibitor bcl-2, the cell adhesion molecule E-cadherin, and the multifunctional protein beta-catenin. Gene amplification and protein overexpression of the growth factor receptors c-erbB-2 and K-sam may be prognostic factors for intestinal-type and diffuse-type gastric cancer, respectively. In addition, genetic instability is commonly seen. There has long been evidence for a genetic predisposition to gastric cancer by epidemiological studies and case reports. Very recently, germ line mutations of E-cadherin have been identified that are responsible for a dominantly inherited form of diffuse-type gastric cancer and could be used to identify individuals that are at high risk.
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PMID:Gastric adenocarcinoma: pathomorphology and molecular pathology. 1131 54

Proteases are linked to the malignant phenotype of different solid tumors. Therefore, the expression of the matrix metalloproteinase (MMP)-2 and MMP-9 and of the serine protease urokinase-type plasminogen activator (uPA) and its inhibitor plasminogen activator inhibitor type 1 (PAI-1) in the progression of ovarian cancer was investigated. Gelatinolytic activity and protein expression of MMP-2 and MMP-9 were analyzed in tissue extracts of 19 cystadenomas and 18 low malignant potential (LMP) tumors, as well as 41 primary tumors of advanced ovarian cancer stage International Federation of Gynecology and Obstetrics IIIc/IV and their corresponding omentum metastases by quantitative gelatin zymography and Western blot. In the same tissue extracts, antigen levels of uPA and its inhibitor PAI-1 were determined by ELISA. Protein expression of pro-MMP-2 (72 kDa) and pro-MMP-9 (92 kDa as well as antigen levels of uPA and PAI-1 were low in benign ovarian tumors but increased significantly from LMP tumors to advanced ovarian cancers. The highest values of all of the proteolytic factors were detected in omentum metastases. Active MMP-2 enzyme (62 kDa) was detected only in ovarian cancer (66%) and corresponding metastases (93%) but never in benign or LMP tumors. The activation rate of MMP-2 to its active isoform was higher in the metastases. Comparing both proteolytic systems, higher PAI-1 concentrations were consistently found in cancers with high pro-MMP-9 expression. These data indicate that members of the plasminogen activator system, as well as the metalloproteinases MMP-2/9, increase with growing malignant potential of ovarian tumors. These findings are of particular relevance to the development of protease inhibitors as new therapeutic approaches in ovarian cancer.
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PMID:Increased expression of matrix metalloproteinases (MMP)-2, MMP-9, and the urokinase-type plasminogen activator is associated with progression from benign to advanced ovarian cancer. 1148 18

A 69-year-old male presented with symptoms of fulminant lung embolism and, despite immediate therapy with plasminogen activator, died of acute right heart failure. At autopsy multiple tumor cell emboli were detected in small pulmonary vessels in addition to widespread liver metastases from an urothelial carcinoma. - In a 23-year-old female a malignant gastric ulcer and multiple liver metastases were diagnosed at initial presentation. She too died from pulmonary hypertension due to a series of lung embolisms which occurred despite heparin therapy. At autopsy, many small pulmonary arteries were filled with adenocarcinoma cells; the primary gastric tumor and liver metastases were confirmed. These cases demonstrate that the shedding of tumor cells from hepatic metastases can obstruct the pulmonary vessels and lead to acute cor pulmonale. Tumor cell emboli should be considered in the differential diagnosis of acute pulmonary hypertension, especially in patients with a known tumor. They may, however, also represent the first clinical signs of previously unrecognized malignancy.
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PMID:[Tumor cell embolism to pulmonary arteries]. 1155 62

Growth of human tumor cells as three-dimensional (3D) multicellular spheroids modifies their invasive properties. Here we study the differences in the biological features of MCF-7, a human breast cancer cell line, and its multidrug resistant variant (MDR-MCF-7) cultured as spheroids or as monolayers. Three-dimensional culture decreased the proliferative rate of both cell lines, reduced the drug sensitivity of MCF-7 cells and did not affect the resistance of MDR-MCF-7 cells. Transmission electron microscopic studies and intercellular junctions labeling showed that MCF-7 spheroids had a junctional system involving E-cadherin, tight-junctions and desmosomes. In MDR-MCF-7 cell spheroids, cell cohesion was mostly due to membrane interdigitations. MDR-MCF-7 cells, but not their parental counterpart, displayed a higher invasive potential when cultured as spheroids, as shown in the Boyden chamber assay. 3D-induced invasiveness was correlated with serine protease and plasminogen activator (PA) secretion. MCF-7 cells did not show any tendency to invade, whatever the mode of culture. These results show that 3D-cultures as spheroids distinctively altered structural features of parental and MDR-MCF-7 cells. In MCF-7 cells, 3D-culture increased cell-cell contacts and drug resistance; in MDR-MCF-7 cells, it induced invasive properties.
Clin Exp Metastasis 2002
PMID:Distinctive alterations of invasiveness, drug resistance and cell-cell organization in 3D-cultures of MCF-7, a human breast cancer cell line, and its multidrug resistant variant. 1196 80

The prognosis of cancer is primarily dependent on its potential to invade and metastasize. Data from both preclinical and clinical studies strongly suggest that serine proteases, as well as their inhibitors and receptor, play a central role in the processes leading to metastasis. We therefore investigated the prognostic value of plasminogen activator inhibitors type 1 (PAI-1) and type 2 (PAI-2) and the combination of both inhibitors in 332 patients with operable breast cancer. PAI-1 and PAI-2 content was measured in the primary tumor cytosols using an enzyme-linked immunosorbent assay. For PAI-1 the median value (3.9 ng/mg protein) was used as cutoff, while the optimized cutoff for PAI-2 (6.5 ng/mg protein) was obtained using the log-rank statistic. After a median follow-up of 46 months 96 (29%) patients relapsed. In univariate analysis patients with a high PAI-1 or a low PAI-2 content had an increased risk of relapse. The difference was statistically significant for PAI-1 (p<0.0001) and almost statistically significant for PAI-2 (p=0.057). Stage, tumor size, differentiation grade, lymph node status and hormone receptor status also showed significant univariate impact on disease-free survival (DFS). In multivariate analysis (Cox model) PAI-1 (p<0.0001, RR=2.78), PAI-2 (p=0.0075, RR=2.17), UICC stage (p=0.0014, RR=2.2), differentiation grade (p=0.0097, RR=1.91) and nodal status (p<0.0001, RR=2.9) retained their significance. When both inhibitors were combined the worst prognosis was observed in patients with simultaneous high PAI-1 and low PAI-2 levels, whereas low PAI-1 in combination with high PAI-2 values indicated a very favorable prognosis. In conclusion, our study showed that both PAI-1 and PAI-2 had independent prognostic value in breast cancer. Combination of both inhibitors further improved the differentiation of patients with respect to prognosis.
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PMID:Prognostic value of plasminogen activator inhibitors in breast cancer. 1211 88

Nasopharyngeal carcinoma (NPC) is a malignant tumor associated with Epstein-Barr virus (EBV). Latent membrane protein-1 (LMP-1) is an EBV-encoded oncoprotein and is detected in approximately 50-70% of patients with NPC. LMP-1 is thought to play an essential role in tumorigenesis of NPC. In addition to its transforming properties, LMP-1 has been suggested to be associated with promotion of metastasis. Metastasis is a phenomenon composed of multiple sequential cascades. Reduction of tumor cell adhesion, degradation of extracellular matrix, basement membrane, enhancement of cell motility, and promotion of neovascularization are thought to be essential steps. LMP-1 down-regulates expression of E-cadherin, induces matrix metalloproteinase-9 and urokinase type-plasminogen activator through activation of NF-kappaB and AP-1, and enhances cell motility via ets-1 activation. LMP-1 also induces vascular endothelial growth factor through cyclooxygenase-2 activation and interleukin-8 through NF-kappaB activation. Clinical studies suggested the association of these factors with metastatic status of patients with NPC. In this review, the role of LMP-1 in the metastasis of NPC is discussed.
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PMID:Promotion of metastasis in nasopharyngeal carcinoma by Epstein-Barr virus latent membrane protein-1. 1216 95


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