Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017638 (glioma)
 30,880 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Matrix metalloproteinases play an important regulatory role in tissue morphogenesis, cell differentiation and motility, and tumor cell invasiveness. We have recently demonstrated elevated activity of the 92 kDa type IV collagenase (MMP-9) in human glioblastoma and in the present study examine the relative amounts of MMP-9 protein and mRNA in human gliomas and as well as the distribution of MMP-9 in human glioma tumors in vivo. Using an enzyme-linked immunosorbent assay for the quantitative determination of MMP-9 protein, we found that levels were significantly higher in malignant astrocytomas, especially in glioblastoma multiforme, than in normal brain tissues and low-grade gliomas. In addition, the amount of MMP-9 mRNA, as determined by northern blot analysis was higher in anaplastic astrocytomas and glioblastoma multiforme than in normal brain tissue and low-grade gliomas. Immunocytochemical staining for MMP-9 showed strong cytoplasmic immunoreactivity in the tumor cells and the proliferating endothelial cells of glioblastoma multiforme and anaplastic astrocytomas. The staining intensity was lowe in low-grade astrocytomas, and was undetectable or very low in normal brain astrocytes. The results indicate that expression of MMP-9 is dramatically upregulated in highly malignant gliomas and correlates with the highly malignant progression of human gliomas in vivo, and support a role for the MMP-9 in facilitating the invasiveness seen in malignant gliomas in vivo.
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PMID:Expression and localization of 92 kDa type IV collagenase/gelatinase B (MMP-9) in human gliomas. 852 11

Matrix metalloproteinases (MMP) are a family of zinc-dependent enzymes which degrade various components of the extracellular matrix (ECM) and play an important role in facilitating tumour cell invasion of the normal brain. The family includes the gelatinases, stromelysins and collagenases. Preliminary studies have shown that there is a differential expression four metalloproteinases in human brain tumour cell lines derived from neoplasms of various histological types and grades of malignancy. Morphological and antigenic changes in human glioma-derived cell lines over many serial in vitro passages have been reported in earlier studies. When established cell lines are maintained in culture over a long period, it is possible that the secretion of enzymes such as metalloproteinases may differ according to the passage level examined. This report presents a study on the secretion of four matrix metalloproteinases - interstitial collagenase (MMP-), 72-kDa and 92-kDa gelatinases (MMP-2 and MMP-9 respectively), and stromelysin (MMP-3) - in three human brain tumour-derived cell lines at sequentially increasing passage numbers, ranging from passage 2 to passage 50; foetal astrocytes were used as a positive control. Reverse zymography and substrate degradation analysis were employed to demonstrate the presence of these enzymes in cell- conditioned culture medium. Aminophenyl mercuric acetate (APMA) was used to activate latent zymogen. Results demonstrate that there is no definite pattern of change in the levels of enzyme secretion common to all cell lines studied. Instead, the fluctuations in APMA- activated metalloproteinase activity in serial passage seems to vary considerably depending on the cell line and the type of enzyme studied. The variation in metalloproteinase expression observed on serial passage may be due to in vitro selection processes or karyotype evolution where the transcription of either the enzyme and/or its inhibitor may be affected. Thus an imbalance of the two products could be occurring in serial passage. Ideally, experiments requiring the measurement of relative enzyme activities should use cultures as near to the biopsy stage as possible, i.e. very low passages, to avoid artifacts that may arise on prolonged culturing.
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PMID:The influence of sequential, in vitro passage on secretion of matrix metalloproteinases by human brain tumour cells. 861 96

Matrix metalloproteinases (MMPs) are zinc-dependent peptidases and are amongst those enzymes responsible for extracellular matrix (ECM) degradation during tumour-cell migration. Gangliosides are a family of acidic membrane glycolipids thought to play a role during cell development, differentiation and oncogenic transformation. In this descriptive study, we investigated the effects of six exogenous gangliosides (GM1, GM3, GD1a, GD1b, GD3 and GT1b) on the secretion of MMP-2 (72 kDa gelatinase or gelatinase-A) and MMP-9 (92 kDa gelatinase or gelatinase-B). Cell-conditioned media from eight human glioma-derived cell-lines served as the source of MMPs and were investigated using SDS-PAGE zymography. Six of the cell lines showed upregulation of secretion of both enzymes by all six gangliosides. Of the remaining two cell lines, one showed inhibition of MMP secretion by all gangliosides and the other had a small but differential response to the range of gangliosides investigated. These results suggest that gangliosides may stimulate glioma cell invasiveness by promoting MMP expression.
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PMID:The effect of exogenous gangliosides on matrix metalloproteinase secretion by human glioma cells in vitro. 908 68

Matrix metalloproteinases (MMPs) are an homologous family of proteolytic enzymes capable of degrading components of the extracellular matrix (ECM) and thereby facilitating the invasion of tumour cells into normal tissues. The neural cell adhesion molecules (NCAMs) of neuronal and glial cells provide a Ca2+-independent mechanism for cell-cell and cell-ECM adhesion. NCAMs are downregulated to promote cell disaggregation during cell migration in the developing nervous system whereas MMPs facilitate migration. Recent studies have shown downregulation of MMP secretion in rat glioma cells transfected with an NCAM cDNA, implying an inverse correlation between NCAM and MMP expression. The purpose of this study was to establish whether such a correlation could be demonstrated in a panel of nine human glioma cell-lines, one metastatic carcinoma and one foetal astrocyte derived cell line. The secretion of two MMPs, 72 kDa gelatinase (MMP-2 or gelatinase-A) and 92 kDa gelatinase (MMP-9 or gelatinase-B), was investigated using SDS-PAGE zymography; NCAM-A was assayed by an immunochemiluminescent assay following SDS-PAGE of whole-cell extracts. An inverse correlation was found between the expression of NCAM-A and that of both MMPs studied although the patterns of expression showed no obvious correlation with histological type or grade of the parent tumours. Our results suggest that downregulation of NCAM-A may contribute to tumour invasiveness by promoting both cell disaggregation and protease secretion.
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PMID:An inverse correlation between expression of NCAM-A and the matrix-metalloproteinases gelatinase-A and gelatinase-B in human glioma cells in vitro. 917 60

A new cell line MGM-1 was established from a primary tumor of the left temporal lobe with histological diagnosis of glioblastoma multiforme, removed from a 64-year-old Japanese male. The patient died of recurrence and unusual extracranial metastases of the tumor 7 months after the surgery. The cultured MGM-1 cells are spindle or polygonal in shape. After serial passages, glial fibrillary acidic protein became negative immunocytochemically in vitro. The modal chromosome number was 61-64. Doubling time and soft agar colony forming efficiency were 42.9h and 0.4%, respectively (at 25th passage). MGM-1 is a highly motile cell line in vitro and its serum-free conditioned medium is chemotactic and chemokinetic for other glioma cells. Secretion of gelatinases (probably MMP-2/72-kDa type i.v. collagenase) and MMP-9/92-kDa type i.v. collagenase) and urokinase-type plasminogen activator were also investigated. MGM-1 would therefore be useful for studying the mechanisms regulating glioma-cell motility and invasion. The MGM-1 cell line has been propagated continuously by serial passages (more than 100 passages) during the past 4 years.
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PMID:Establishment and characterization of a new human glioblastoma cell line (MGM-1) with highly motile phenotype. 923 71

Proteases such as matrix metalloproteinases (MMPs), cysteine- and serine-proteinases are capable of degrading extracellular matrix and basement membranes and have been implicated in human brain tumours. MMPs are a homologous family of zinc-dependent proteases. Within this group, attention has been focused on the gelatinases (MMP-2 and MMP-9) which are thought to play an important role in tumour progression. The cysteine proteinases which have received most attention in relation to tumour progression are cathepsin B (CB) and to a lesser extent cathepsin L (CL). Among the serine proteinases, urokinase plasminogen activator and its receptor have been the subject of much investigation. In the present review, evidence from current literature on the possible role or significance of serine- and cysteine-proteinases and MMPs and their inhibitors in human brain tumours is discussed with special reference to gliomas. Although direct evidence is reported for MMPs and serine proteinases to support their role in glioma invasion, much of the evidence for the involvement of cysteine proteinases remains circumstantial.
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PMID:Proteases and their inhibitors in human brain tumours: a review. 942 49

Our previous studies demonstrated that matrix metalloproteinase (MMP-9) levels were significantly higher in human glioblastoma tissue samples than in low-grade brain tumors and normal brain tissue (Rao et al., Cancer Res. 53, 2208-2211, 1993). In the present study, we measured the levels of MMP-2 and MMP-9 during the growth of glial tumors in nude mice by intracerebral injection of glioblastoma cells. Using gelatin zymography, densitometry, and an enzyme-linked immunosorbent assay, we found that the enzyme activity and protein count of MMP-2 and MMP-9 were a respective 3- to 10- and 2- to 30-fold higher in tumors at day 14 and 28 than in normal tissue. Immunohistochemical staining for MMP-9 showed strong immunoreactivity in tumor cells and the staining intensity was much higher at day 28, compared to day 14. These results suggest that upregulation of MMP-9 plays a major role in the glioma tumor growth in vivo.
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PMID:Elevated levels of Mr 92,000 type IV collagenase during tumor growth in vivo. 979 25

Malignant progression in gliomas is correlated with increased migratory capacity which involves metalloproteolytic activity. Here, we report that ectopic expression of BCL-2 in two malignant glioma sublines markedly promoted glioma cell migration from spheroids and invasion into Matrigel-coated membranes. Invasion of fetal rat-brain aggregates was enhanced by BCL-2. Zymography revealed activation of matrix metalloproteinase-2 (MMP-2) in BCL-2-expressing cells. BCL-2 expressing cells showed an increase in MMP-2/-3/-12 (LN-18), and MMP-9/-12 and cell surface urokinase-type plasminogen activator (u-PA) (LN-229) mRNA and a reduction in tissue inhibitors of metalloproteinases (TIMP)-2 mRNA (LN-229). Taken together, we propose a novel function for BCL-2 in the malignant phenotype of glioma cells, that is, to enhance migration and invasion by altering the expression of a set of metalloproteinases and their inhibitors.
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PMID:BCL-2 promotes migration and invasiveness of human glioma cells. 987 14

Matrix metalloproteinases have been implicated to play a vital role in glioma invasion as they degrade extracellular matrix to facilitate the subsequent migration of tumor cells into the surrounding brain tissue. The cytokine Interleukin-10 (IL-10) was detected recently in glial tumors in vivo. Expression of specific IL-10 mRNA as well as blood serum levels of IL-10 in glioma patients increased with malignancy suggesting a functional role of IL-10 in glioma progression. Moreover, glioma cell migration in vitro was enhanced in the presence of IL-10. We therefore investigated the expression of the matrix metalloproteinases (MMPs) stromelysin-1 (MMP-3), 72-kDa collagenase (MMP-2), 92-kDa collagenase (MMP-9), matrilysin (MMP-7) and the human macrophage metalloelastase (MMP-12). In addition, a possible relation between exposure of glioma cells to IL-10 and invasiveness of these cells due to MMP expression was analyzed. Experiments with Matrigel coated Boyden chambers revealed a pronounced dose dependent effect of IL-10 on glioma invasiveness. The synthetic MMP-inhibitor Marimastat markedly reduced cell invasion in the Boyden chambers confirming the significance of MMPs in the process of invasion. Subsequently, the expression level of MMPs and the serine protease uPA was investigated in 7 glioma cell lines (U373, GaMG, U251, GHE, SNB19, U138 and D54) by RT-PCR. In all but one cell line no enhancement of MMP expression by IL-10 was detected. Matrilysin in U373 cells was the only protease found to be upregulated in the presence of IL-10 dependent on cell density. The present data suggest that IL-10 related effects on the invasive properties of the cell lines are not directly mediated by an upregulation of matrix metalloproteinase expression.
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PMID:Expression of matrix metalloproteinases in human glioma cell lines in the presence of IL-10. 989 93

Cell-matrix interactions exert a profound influence on cell function and behavior. Our earlier observations suggested that disruption of the actin cytoskeleton results in the inhibition of phorbol ester-induced matrix metalloproteinase (MMP)-9 expression. In this study, to understand the role of protein tyrosine phosphatases in matrix metalloproteinase-9 expression, we treated glioblastoma cells with vanadate and phenylarsine oxide (PAO), which are inhibitors of protein tyrosine phosphatases. Vanadate and PAO inhibited expression of phorbol ester-induced MMP-9 as well as constitutive expression of matrix metalloproteinase-2 in a dose- and time-dependent fashion. An assay of the activity of phosphotyrosine phosphatase (PTPase) indicated that vanadate-treated cells had reduced PTPase activity compared with that of untreated controls. Vanadate and PAO also inhibited actin polymerization, cell spreading, migration, and invasion of glioma cells. Furthermore, elevated levels of protein tyrosine phosphorylation were observed in vanadate- and PAO-treated cells in both a concentration- and time-dependent fashion and were seen to have an inverse correlation with focal adhesion kinase protein expression. These results suggest that vanadate and PAO inhibited migration and invasion of glioma cells by their effect on the cytoskeleton and inhibition of MMP expression.
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PMID:Altered actin cytoskeleton and inhibition of matrix metalloproteinase expression by vanadate and phenylarsine oxide, inhibitors of phosphotyrosine phosphatases: modulation of migration and invasion of human malignant glioma cells. 1056 4


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