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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Tumor invasion and metastasis formation are major obstacles for successful cancer therapy. Metastasis is a complex multistep process that requires sequential interactions between the invasive cell and the extracellular matrix. A model system for tumor invasion of extracellular matrix barriers has been developed, and application of this model has facilitated our understanding of the molecular mechanisms of metastasis formation. This model consists of three steps: tumor cell adhesion, extracellular matrix proteolysis, and cell migration. The role of the matrix metalloprotease enzymes in tumor cell-mediated extracellular matrix proteolysis is well established. We review the functional domain structure of the matrix metalloprotease enzymes in general and specifically the interaction of metastasis-associated gelatinase A (72-kDa type IV collagenase) with the tissue inhibitor of metalloproteases-2 (TIMP-2). We also discuss the physiologic activation of the matrix metalloprotease enzymes and the specific cellular mechanism of action of gelatinase A.
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PMID:Extracellular matrix 6: role of matrix metalloproteinases in tumor invasion and metastasis. 826 28

Radiolabeled substrate degradation assays and gelatin zymography are routinely employed to assay 72 kDa gelatinase A (MMP-2) and 92 kDa gelatinase B (MMP-9) in biological fluids. Enzyme-linked immunosorbent assays (ELISA) have recently been developed for the quantitation of these matrix metalloproteinases (MMP). In this study, we have compared ELISA to standard substrate degradation assays for measurement of MMP-2 and MMP-9 in human plasma and tumor-conditioned media. Gelatin Sepharose chromatography and gel filtration chromatography were employed as partial purification procedures for MMP-2 and MMP-9. The ELISA data for MMP-2 and MMP-9 are linear on a log:log regression curve over a wide range of MMP concentrations and are specific for the designated gelatinase, with no overlap detected with related metalloproteinases. The minimum detectable concentrations of MMP-2 and MMP-9 were approximately 0.5 ng/ml and 0.2 ng/ml, respectively, in the ELISA as compared to 4 ng/ml and 3 ng/ml, respectively, in gelatin zymography. The [3H]gelatin degradation assay required a combination of > 50 ng/ml of MMP-2 and MMP-9 for detection. Although gelatin zymography was less sensitive than ELISA (primarily due to the smaller sample volume employed) and was more difficult to quantitate, this procedure offers the important advantage of being able to distinguish between latent and activated gelatinases.
Clin Exp Metastasis 1994 Jan
PMID:Comparison of techniques for measurement of gelatinases/type IV collagenases: enzyme-linked immunoassays versus substrate degradation assays. 828 15

A new cultured cell line (KG-2) derived from human renal cell carcinoma and a metastatic model in nude mice were studied. KG-2 was cultured from renal cell carcinoma (clear cell carcinoma) of the left kidney. In vitro doubling time of KG-2 was approximately 50 hours. KG-2 cells produced tumors in both the subcutaneous and renal sub-capsular space in nude mice, with tumorigenicity of 75%, showing no difference between the two sites. Histologically, tumors formed in the subcutaneous sites were hypovascular granular cell carcinoma. Moreover, each tumor was encapsulated by a thick fibrous capsule and never produced distant metastasis or invasion into the surrounding tissue. However, tumors formed in the subrenal capsular space were clear cell carcinoma. These tumors were hypervascular, and produced distant metastases. The most common metastatic site was the lung. Immunohistochemical analysis using anti-human collagenase type IV antibody on tumors formed in subcutaneous and subrenal capsular sites demonstrated that the expression of this enzyme in tumors formed in the subrenal capsular space was much higher than that in tumors formed in the subcutaneous site. Additionally, immunohistochemical study using anti-mouse collagen type IV antibody, a major components of the vascular wall, demonstrated many small densely growing vessels in tumors formed in the subrenal capsular space. In contrast, few vessels were produced in tumors formed in subcutaneous sites. These findings suggest that factors relating to the different injection sites may regulate the production of collagenase type IV secreted by KG-2 cells and neovascularity in nude mice. This metastatic model may be useful in the study of the mechanism of cancer metastases.
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PMID:[Establishment and characterization of a new human renal cell carcinoma cell line (KG-2) and metastatic model in nude mice]. 834 19

Matrix metalloproteinases (MMPs) are a group of enzymes thought to be responsible for both normal connective-tissue-matrix remodelling and the accelerated breakdown associated with tumor development. These MMPs and tissue inhibitor of MMPs (TIMP1) could be expressed by either the cancer or the stromal cells. Expression of mRNAs encoding interstitial collagenase (MMP1), 72-kD type IV collagenase (MMP2) and stromelysin (MMP3), which are probably involved in tumor invasion and metastasis, and of TIMP1 were studied in human mammary pathology by in situ hybridization and Northern blot analysis. Out of 6 benign lesions, 2 expressed MMP2 mRNAs. mRNAs encoding MMP1 and MMP3 were detectable in occasional stromal and tumor cells in 2 out of 17 carcinomas. Thirteen out of 17 cancers expressed MMP2 mRNA throughout the tumor in stromal cells close to noninvasive tumor clusters and well-differentiated invasive cancer cells. TIMP1 mRNA expression was detected in noninvasive and well-differentiated invasive tumor cells. These data suggest that there is a cooperation between tumor and stromal cells, in particular for the production of 72-kD type IV collagenase, involved in the disruption of basement membranes. A lack of TIMP1 expression from invasive cancer cells would also contribute to matrix destruction.
Invasion Metastasis 1993
PMID:Detection and localization of mRNAs encoding matrix metalloproteinases and their tissue inhibitor in human breast pathology. 840 9

Overproduction of matrix metalloproteinases (MMPs) is a common characteristic of metastatic cancer cells. Since MMPs can be identified in plasma, we proposed that enhanced MMP-9 secretion by invasive cancer cells may be detected by plasma assay. To this end, we developed a specific sandwich enzyme-linked immunosorbent assay which uses two mouse monoclonal antibodies to human M(r) 92,000 type IV collagenase (MMP-9). The plasma concentration of MMP-9 (mean +/- SD) in 60 healthy subjects (9 +/- 11 ng/ml), 136 patients without cancer, and 179 patients with cancer of the lung, genitourinary tract, or lymphomas-leukemias did not differ significantly. In contrast, plasma MMP-9 was significantly increased (P < 0.01) in 122 patients with gastrointestinal tract cancer and breast cancer (18 +/- 23 and 21 +/- 22 ng/ml, respectively). Whereas carcinoembryonic antigen levels were significantly increased in patients with stage IV gastrointestinal cancer, MMP-9 concentrations were not significantly increased in patients with metastatic disease as compared to those with nonmetastatic cancer. Combining both assays improves sensitivity of detection of colon cancer. MMP-9 was also significantly increased during pregnancy which is consistent with the extensive ongoing tissue remodeling and the leaching of the tissue proteinase into plasma.
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PMID:M(r) 92,000 type IV collagenase is increased in plasma of patients with colon cancer and breast cancer. 841 38

To investigate the effect of matrix-degrading enzymes on the malignant potential of oral squamous cell carcinoma, the expression of matrix metalloproteinase-2 (MMP-2/72-kD gelatinase/type IV collagenase) in 46 patients who had neck surgery for oral cancer was studied immunohistochemically. In 20 of 26 patients (76.9%) with lymph node metastases, proMMP-2 was strongly expressed, whereas the production of proMMP-2 in tissue was detected only in 5 of 20 patients (25%) who had no lymph node metastases. In tissue specimens, proMMP-2 was expressed in a diffuse invasive mode and in the advancing front of cancer. Because MMP-2 can degrade type IV collagen composed of basement membrane, these results suggest that the in vivo production of the enzyme by cancer is an indicator of the degree of malignancy, and that the analysis of proMMP-2 expression is useful to evaluate the malignant potential in individual oral squamous cell carcinoma.
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PMID:Expression of matrix metalloproteinase-2 related to lymph node metastasis of oral squamous cell carcinoma. A clinicopathologic study. 842 10

Metalloproteases are implicated in conferring invasive properties to tumor cells. We show here that treatment of ras-oncogene-transformed rat fibroblasts with dimethylsulfoxide (DMSO) results in a reversible decrease in stromelysin mRNA. Furthermore, stromelysin expression was found to be repressed by DMSO, but not by glucocorticoid hormone, in a fibrosarcoma cell line showing low AP-1 (fos/jun) transcription factor activity. In two fibrosarcoma cell lines which express high levels of stromelysin and low levels of 68 kDa type IV collagenase, the DMSO-induced decrease in stromelysin expression was paralleled by a decreased invasive propensity.
Clin Exp Metastasis 1993 Jan
PMID:Repression of stromelysin metalloprotease expression in rat fibrosarcoma cells by dimethylsulfoxide. 842 9

The expression of both 92- and 72-kDa gelatinases has been studied in 20 samples of human breast carcinoma by the technique of gelatin zymography. This technique allowed the relative amount of each gelatinase to be determined in small samples of tissue (< 10 mg). More importantly, active and latent forms of the two gelatinases were resolved. Two samples (10-20 mg) were cut from each piece of tumour in order to monitor the variability of gelatinase distribution within that section of tumour. The 72-kDa latent progelatinase was present in 15 of the 20 tumours, with trace amounts in two others. The 62-kDa activated form of this gelatinase was detected in all 15 of the tumours in which the latent form was present. The 92-kDa latent progelatinase was present in 11 of the 20 tumours, with trace amounts in four others. However, the 82-kDa activated form of this gelatinase was only clearly detected in two tumours, although three others showed the presence of trace amounts. The ratio of active to latent forms of the 72-kDa gelatinase ranged from 0.9 to 3.6. There were no marked correlations between gelatinase expression and established staging and prognostic markers. Analysis of three samples of fibroadenoma revealed only very low levels of gelatinase expression. On the basis of these results, activation of the 72-kDa progelatinase appears to be a more common event in invasive breast carcinoma than activation of the 92-kDa progelatinase. However, neither proteinase showed a correlation with metastatic progression, as measured by lymph node involvement.
Clin Exp Metastasis 1993 Mar
PMID:Expression of activated gelatinase in human invasive breast carcinoma. 844 10

The expression of the stromelysin 3 (ST3) gene, which encodes a putative matrix metalloproteinase, was studied during breast cancer progression. The ST3 gene is expressed in all invasive breast carcinomas, in a number of their metastases, and in some in situ carcinomas where the probability of detecting ST3 transcripts correlates with the known risk of these carcinomas to become invasive. ST3 RNA and protein were specifically detected in fibroblastic cells immediately surrounding the neoplastic cells in both primary and metastatic tumors. This expression pattern distinguishes the ST3 gene from other matrix metalloproteinase genes, most notably from the 72-kDa type IV collagenase gene, which can be expressed in fibroblastic cells distributed throughout the stroma of primary breast carcinomas. Furthermore, high levels of 72-kDa type IV collagenase, but not of ST3 transcripts, are detected in benign breast fibroadenomas. Interestingly, the urokinase and ST3 genes exhibit very similar patterns of expression in breast carcinomas, which suggests that their products may cooperate during cancer progression.
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PMID:Stromelysin 3 belongs to a subgroup of proteinases expressed in breast carcinoma fibroblastic cells and possibly implicated in tumor progression. 844 98

Motility factors play a major role in tumor cell invasion and metastases. The biochemical properties of various motility factors; the receptor mediated mechanism of action; the role of microtubules; the potential influence of oncogenes; and the influence of motility factors on type IV collagenase secretion and invasion are discussed. We report on expression of a 70 kDa motility factor, termed invasion stimulating factor (ISF), in human prostatic PC-3 sublines. Boyden chamber chemotactic assays and measurements of type IV collagenase synthesis and secretion suggest that an ISF-receptor dependent mechanism influences tumor cell invasion and protease secretion. Taken together, the evidence that autocrine motility factors play an essential role in tumor cell invasion and metastases is compelling.
Cancer Metastasis Rev 1993 Mar
PMID:Autocrine factors, type IV collagenase secretion and prostatic cancer cell invasion. 844 26


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