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)

Matrix metalloproteases are secreted by mammalian cells as zymogens and, upon activation, initiate tissue remodeling by proteolytic degradation of collagens and proteoglycans. Activation of the secreted proenzymes and interaction with their specific inhibitors determine the net enzymatic activity in the extracellular space. We have previously demonstrated that 72T4Cl can be activated by a plasma membrane-dependent mechanism specific for this enzyme. Here, we report purification of the membrane activator of 72T4Cl, which is a new metalloprotease identical to a recently cloned membrane-type matrix metalloprotease (MT-MMP). We demonstrate that activated MT-MMP acts as a cell surface tissue inhibitor of metalloprotease 2 (TIMP-2) receptor with Kd = 2.54 x 10(-9) M. The activator.TIMP-2 complex in turn acts as a receptor for 72T4Cl (Kd = 0.56 x 10(-9) M, binding to the carboxyl-end domain of the enzyme. Activation of 72T4Cl on the cell membrane provides a basic mechanism for spatially regulated extracellular proteolysis and presents a new target for prognosis and treatment of metastatic disease. The activation, purified as a tri-molecular complex of MT-MMP.TIMP2.carboxyl-end domain of 72T4Cl, is itself an activated form of MT-MMP, posing the following question: what is the mechanism of the activator's activation?
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PMID:Mechanism of cell surface activation of 72-kDa type IV collagenase. Isolation of the activated form of the membrane metalloprotease. 789 Jun 45

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

A hallmark of invasive tumors is their ability to effect degradation of the surrounding extracellular matrix (ECM) by the local production of proteolytic enzymes, such as the matrix metalloproteases (MMPs). In this paper, we demonstrate that the invasion of human gliomas is mediated by a 72 kDa MMP, referred to as MMP-2, and provide further evidence that the activity of MMP-2 is regulated by protein kinase C (PKC). The invasiveness of five human glioma cell lines (A172, U87, U118, U251, U563) was assessed in an in vitro invasion assay and was found to correlate with the level of MMP-2 activity (r2 = 0.95); in contrast, the activity of this 72 kDa metalloprotease was barely detectable in non-invasive control glial cells (non-transformed human astrocytes and oligodendrocytes). Treatment with 1,10-phenanthroline, a metalloprotease inhibitor, or with a synthetic dipeptide, containing a blocking sequence (ala-phe) specific for MMPs, resulted in a > 90% reduction in glioma invasion. Furthermore, this MMP-2 activity could be inhibited by the treatment of tumor cells with calphostin C, a specific inhibitor of PKC. Glioma cell lines treated with calphostin C demonstrated a dose-dependent decrease (IC50 = 30 nM) in tumor invasiveness with a concomitant reduction in the activity of the MMP-2. Conversely, treatment of non-invasive control astrocytes with a PKC activator (phorbol ester) led to a corresponding increase in their invasiveness and metalloprotease activity. These findings support the postulate that MMP-2 activity constitutes an important effector of human glioma invasion and that the regulation of this proteolytic activity can be modulated by PKC.
Clin Exp Metastasis 1996 Oct
PMID:Glioma invasion in vitro: regulation by matrix metalloprotease-2 and protein kinase C. 887 36

Members of the matrix metalloprotease (MMP) family are implicated in the progression of several malignancies including prostate cancer due to their ability to break down extracellular matrix (ECM) components. In this study, we have evaluated the ability of a synthetic MMP inhibitor (A-177430) to block tumor growth and metastases in a syngeneic model of rat prostate cancer. In an in vitro substrate assay, A-177430 exhibited nanomolar potency (IC(50) 2-6 nM) against the enzymatic activity of several MMPs. For in vivo studies, male Copenhagen rats were injected s.c. with Mat Ly Lu rat prostate cancer cells (1 x 10(6) cells ) into the right flank and animals were administered i.p.with different doses (10-100 mg/kg per day) of A-177430 for 16 days. Administration of A-177430 resulted in a dose-dependent decrease in tumor volume as compared to a control group of animals receiving vehicle alone. The maximum dose (100 mg/kg per day) of A-177430 exhibited complete arrest in tumor growth and prevented the development of macroscopic tumor metastases to lungs without exhibiting any noticeable side effects. Histologic examination of primary tumors from experimental animals showed extensive tumor necrosis and decreased tumor angiogenesis as determined by factor VIII staining of primary tumors following A-177430 treatment. These primary tumors from experimental animals also exhibited a significant increase in tumor cell DNA fragmentation as determined by TUNEL assay. Collectively, these results demonstrate the ability of MMP inhibitors to block tumor growth and metastases by blocking ECM degradation and by inhibiting tumor angiogenesis and promotion of prostate cancer cell apoptosis in vivo.
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PMID:Synthetic inhibitor of matrix metalloproteases decreases tumor growth and metastases in a syngeneic model of rat prostate cancer in vivo. 1086 87

Matrilysin is a matrix metalloprotease (MMP) overexpressed in a number of cancers including skin, head and neck squamous cell carcinomas, and prostate and colon adenocarcinomas. Matrilysin has been shown to play a role in the degradation of the basement membrane that separates epithelium from stroma allowing tumor cells to intravasate into the bloodstream and metastasize. Here, we show that an oral squamous cell carcinoma cell line (SCC-25) expresses low levels of promatrilysin when cultured alone. However, when SCC-25 cells are cocultured with human foreskin fibroblasts (HFF), there is a 40-fold induction of promatrilysin expression. We tested whether this induction of promatrilysin expression was due to the release of paracrine factors, cell-cell interactions, or cell-matrix interactions. Our results indicate induced promatrilysin expression is the result of both cell-cell and cell-matrix interactions. We demonstrate that beta1 integrins as well as cadherins, specifically N-cadherin and E-cadherin, are involved in the induction of promatrilysin expression. Our results are of general interest in relation to the regulation of MMP expression through cell surface receptor regulation. Further investigation may lead to the identification of novel targets for suppression of invasion and metastasis in oral tumors.
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PMID:Integrin- and cadherin-mediated induction of the matrix metalloprotease matrilysin in cocultures of malignant oral squamous cell carcinoma cells and dermal fibroblasts. 1164 Aug 89

The effect of a naturally occurring flavonoid apigenin on the development of bombesin-enhanced peritoneal metastasis from intestinal adenocarcinomas induced by azoxymethane was investigated in male Wistar rats. From the start of the experiment, rats were given weekly s.c. injections of azoxymethane (7.4 mg/kg body weight) for 10 weeks and s.c. injection of bombesin (40 microg/kg body weight) every other day, and from week 16, s.c. injections of apigenin (0.75 or 1.5 mg/kg body weight) every other day until the end of the experiment in week 45. Bombesin significantly increased the incidence of intestinal tumors and cancer metastasis to the peritoneum in week 45. It also significantly increased the labeling index of intestinal cancers. Although administration of apigenin at either dose with bombesin had little or no effect on the enhancement of intestinal carcinogenesis by bombesin, the location, histologic type, depth of involvement, infiltrating growth patterns and labeling index, it was found to decrease significantly the incidence of cancer metastasis. Apigenin significantly decreased the incidence of lymphatic vessel invasion of adenocarcinomas, which was enhanced by bombesin. In vitro experiments revealed that apigenin inhibited bombesin-enhanced phosphorylation of mitogen-activated protein kinase (MAPK), but not matrix metalloprotease (MMP)-9 expression. Our findings indicate that apigenin inhibits cancer metastasis through inhibition of phosphorylation of MAPK.
Clin Exp Metastasis 2000
PMID:Suppression by apigenin of peritoneal metastasis of intestinal adenocarcinomas induced by azoxymethane in Wistar rats. 1182 69

Metastatic brain tumors are the most common complication of systemic cancer and affect 20-40% of all adult cancer patients. Whole-brain radiotherapy and surgical resection of accessible, solitary lesions have been the mainstay of treatment. Recently, chemotherapy has become a more viable treatment option for metastatic brain tumors. Many different drugs and administrative approaches have been shown to be clinically active. Traditional chemotherapy given before or during irradiation can be effective with agents such as cyclophosphamide, cisplatin and etoposide. Nontraditional approaches, such as tempozolomide and intra-arterial administration of carboplatin, have demonstrated activity against recurrent metastatic disease. In early clinical trials of interstitial chemotherapy, biodegradable polymers have shown some clinical efficacy and have been well-tolerated. Molecular approaches are also under investigation in response to new information regarding the metastatic phenotype. Potential targets include growth factor receptors and other protein tyrosine kinases, internal signal transduction pathways, ras activation and matrix metalloprotease activity. New clinical trials will be needed to investigate these new molecular-based therapeutics, alone and in combination with currently available treatment options, to determine the optimal application of chemotherapy to metastatic brain tumors.
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PMID:Chemotherapy for the treatment of metastatic brain tumors. 1238 18

CMT-3 is an orally active matrix metalloprotease inhibitor, and one of a series of inhibitors of multiple proteases and cytokines, under development by CollaGenex. The compound is currently undergoing phase II trials for the potential treatment of cancer, in particular metastatic cancer and HIV-related Kaposi's sarcoma.
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PMID:CMT-3. CollaGenex. 1476 33

Metastasis is a multi-step process involved in the progression of breast cancer to a disease with poor prognosis. Growth factor and/or growth factor receptor over- expression have been reported to play an important role in this process. The 88 kDa glycoprotein PC cell-derived growth factor (PCDGF/GP88), also known as progranulin, has been shown to play a major role in breast tumorigenesis by stimulating proliferation, mediating survival and conferring resistance to tamoxifen. In the present paper, the metastatic potential of PCDGF/GP88 was examined in breast cancer. Using MCF-7 cells, we showed that PCDGF/GP88 over-expression stimulated anchorage-independent cell growth and accelerated cell migration through matrigel. Similar results were obtained with MCF-7 cells treated exogenously with PCDGF/GP88. Furthermore, gelatin zymograph and immunoblot revealed that matrix metalloprotease-9 was up-regulated by PCDGF/GP88. PCDGF/GP88 stimulated VEGF expression in MCF-7 cells. These results suggest that PCDGF/GP88 could act to promote metastasis and angiogenesis in human breast cancer cells in addition to stimulating their proliferation and survival.
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PMID:PC cell-derived growth factor (PCDGF/GP88, progranulin) stimulates migration, invasiveness and VEGF expression in breast cancer cells. 1511 9

Conventional stroke risks are thought responsible for most cerebral ischemic events (CIE) in adult cancer patients. Also suspected as a risk is cisplatin chemotherapy, alone or in combination with tumor angiogenesis inhibitor. We investigated whether treatment or tumor characteristics, independently of conventional stroke risks, are associated with CIE in a retrospective cohort study of 1,559 patients with advanced non-small cell lung cancer or hormone-refractory prostate cancer followed during 3 clinical trials of matrix metalloprotease inhibitor (prinomastat) versus placebo, with chemotherapy (gemcitabine/cisplatin, paclitaxel/carboplatin or mitoxantrone/prednisone). During 11,907 patient-months, 28 CIE (17 cerebral infarction, 11 transient ischemic attack) were diagnosed in 24 patients, all but 1 over 55 years. Neither prinomastat, platinum-based chemotherapy nor their combination was associated with CIE after age 55. However, such events were predicted by the presence of distant metastases in the liver or lungs and not in distant lymph nodes (hazard estimate 4.6, 95% CI 2.0-10.5, adjusted for conventional stroke risks). Further studies are needed to verify this preliminary finding and determine its generalizability to advanced tumors other than lung or prostate cancer.
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PMID:Cerebral ischemic events in patients with advanced lung or prostate cancer. 1583 61


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