Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.21.73 (urokinase-type plasminogen activator)
 10,685 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Proteases and their inhibitors have been shown to play roles in tumor invasion and metastasis in a number of experimental models. Recently, relative increases in the amounts of urokinase type plasminogen activator (uPA) and plasminogen activator inhibitor-1 (PAI-1) in tumor samples have been correlated with poorer, pathological grade, shorter disease-free interval, and shorter survival. To date, all studies investigating the prognostic significance of proteases and their inhibitors have been limited to extracranial cancer. In this article, we review the literature and present our data on the prognostic significance of proteases in human brain tumors. High levels of uPA were seen in malignant glioma and metastatic tumors (n = 82), whereas normal levels of uPA were found in low-grade gliomas. Analysis with magnetic resonance imaging (MRI) demonstrated a significant correlation between high levels of uPA and necrosis and edema (n = 50; P < 0.05). Similarly, patients with high levels of uPA had shorter survival than did patients with low levels of uPA. Tissue-type plasminogen activator (tPA), which was virtually absent in glioblastoma multiforme (GBM), colon lung, and breast metastasis, was found in normal quantities in anaplastic astrocytoma (AA), low-grade glioma (LGG), and meningioma. Melanoma had significantly more tPA activity than normal brain did. A reverse correlation was found between tPA and MRI findings of necrosis, enhancement, and edema. Similarly, patients with no detectable tPA activity had shorter survival than did patients with detectable tPA activity. We conclude that high levels of uPA and absent tPA activity correlate with histologically malignant brain tumors, aggressive characteristics, and shorter survival.
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PMID:Prognostic significance of proteolytic enzymes in human brain tumors. 753 61

Protease inhibitors regulate a variety of physiological and pathological processes including angiogenesis, embryo implantation, intravascular fibrinolysis, wound healing, and tumor invasion. Tissue factor pathway inhibitor (TFPI) 2 is a Mr 32,000 Kunitz-type serine protease inhibitor that inhibits plasmin, trypsin, chymotrypsin, cathepsin G, and plasma kallikrein but not urokinase-type plasminogen activator, tissue plasminogen activator, or thrombin. In this study, we determined the relative amounts of TFPI-2 in low-, intermediate-, and high-grade human glioma cell lines and tumor tissue samples. TFPI-2 protein and mRNA levels (measured by Western and Northern blotting) were highest in low-grade glioma cells (Hs683), lower in anaplastic astrocytoma cells (SW1088 and SW1783), and undetectable in high-grade glioma cells (SNB19). Analysis of TFPI-2 protein in human normal brain and in glioma tumor tissues for TFPI-2 revealed the highest levels in normal brain, lesser amounts in low-grade gliomas and anaplastic astrocytomas, and undetectable amounts in glioblastomas. In situ hybridization of TFPI-2 mRNA with normal brain tissues revealed the greatest positivity in neurons, with moderate positivity in both glial and endothelial cells and moderate, little, or no TFPI-2 mRNA in low-grade glioma, anaplastic astrocytoma, and glioblastoma tumor tissue samples, respectively. We also found that recombinant TFPI-2 inhibited the invasiveness of SNB19 glioblastoma cells in a Matrigel assay in a dose-dependent manner. Collectively, these results suggest that TFPI-2 has a regulatory role in the invasiveness of gliomas in vitro and in vivo.
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PMID:Expression of tissue factor pathway inhibitor 2 inversely correlates during the progression of human gliomas. 1129 50

Sodium phenylbutyrate is a biological-response modifier that acts as a dose-dependent inhibitor of glioma cell proliferation, migration, and invasiveness in vitro, possibly by inhibition of urokinase and c-myc pathways. Despite its biological activity in vitro, there have not been any prior reports of efficacy in the treatment of human malignant gliomas. We report a 44-year-old female with a recurrent, multicentric, malignant glioma who experienced a durable remission lasting more than four years. The patient initially presented with seizures caused by a biopsy-proven anaplastic astrocytoma of the frontal lobe. The patient was treated with radiation therapy and Procarbazine-CCNU-Vincristine (PCV). However, the tumor progressed and extended to the corpus callosum with midline shift, refractory to four cycles of continuous 72-h infusion of BCNU/Cisplatinum. Additional enhancing lesions appeared in the left frontal and left temporal lobes. The patient was started on sodium phenylbutyrate, 18 g daily in three divided oral doses, and reduced to 9 g/day and eventually to 4.5 g/day to eliminate mild, reversible side effects. Four years later, the patient has a KPS functional score of 100%. Phenylbutyrate is a well-tolerated, oral agent that shows potential for the treatment of malignant gliomas. Further studies should be considered to identify a subset of patients that have tumors sensitive to phenylbutyrate, either as a single agent or in combination with radiation therapy or other chemotherapeutic agents.
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PMID:Complete response of a recurrent, multicentric malignant glioma in a patient treated with phenylbutyrate. 1501 93