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 metalloproteinase 9 (MMP-9) is known to play a major role in cell migration and invasion in both physiological and pathological processes. Our previous work has shown that increased MMP-9 levels are associated with human glioma tumor progression. In this study, we evaluated the ability of an adenovirus containing a 528 bp cDNA sequence in antisense orientation to the 5' end of the human MMP-9 gene (Ad-MMP-9AS) to inhibit the invasiveness and migratory capacity of the human glioblastoma cell line SBN19 in in vitro and in vivo models. Infection of glioma cells with Ad-MMP-9AS reduced MMP-9 enzyme activity by approximately 90% compared with mock- or Ad-CMV-infected cells. Migration and invasion of glioblastoma cells infected with Ad-MMP-9AS were significantly inhibited relative to Ad-CMV-infected controls in spheroid and Matrigel assays. Intracranial injections of SNB19 cells infected with Ad-MMP-9AS did not produce tumors in nude mice. However, injecting the Ad-MMP-9AS construct into subcutaneous U87MG tumors in nude mice caused regression of tumor growth. These results support the theory that adenoviral-mediated delivery of the MMP-9 gene in the antisense orientation has therapeutic potential for treating gliomas.
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PMID:Adenovirus-mediated expression of antisense MMP-9 in glioma cells inhibits tumor growth and invasion. 1243 51

A hallmark of highly malignant human gliomas is their infiltration of the brain. We analyzed a large number of primary human glioma biopsies and found high levels of expression of an angiogenic regulator, angiopoietin-2 (Ang2), in the invasive areas, but not in the central regions, of those tumors. In the invasive regions where Ang2 was overexpressed, increased levels of matrix metalloprotease-2 (MMP-2) were also apparent. Consonant with these features, intracranial xenografts of glioma cells engineered to express Ang2 were highly invasive into adjacent brain parenchyma compared with isogenic control tumors. In regions of the Ang2-expressing tumors that were actively invading the brain, high levels of expression of MMP-2 and increased angiogenesis were also evident. A link between these two features was apparent, because stable expression of Ang2 by U87MG cells or treatment of several glioma cell lines with recombinant Ang2 in vitro caused activation of MMP-2 and acquisition of increased invasiveness. Conversely, MMP inhibitors suppressed Ang2-stimulated activation of MMP-2 and Ang2-induced cell invasion. These results suggest that Ang2 plays a critical role in inducing tumor cell infiltration, and that this invasive phenotype is caused by activation of MMP-2.
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PMID:Angiopoietin-2 induces human glioma invasion through the activation of matrix metalloprotease-2. 1286 Oct 74

We have elucidated the pharmacological action of the anti-matrix metalloproteinase inhibitor BE16627B on glioma cells. The study was limited to the noncytotoxic dose range. The aim of the study was to investigate whether the cytotoxicity of BE16627B, an anti-MMP agent, is related to apoptosis in the human malignant glioma cell lines U87MG, U251MG, and U373MG. MTT assay was performed to detect the cytotoxic dose range. Agarose gel electrophoresis was performed with purified genomic DNA following exposure to 20 to 500 microM BE16627B for 24 h, compared with 0 microM for the control group. Transmission electron microscopy (TEM) was employed to study nuclear fragmentation following exposure to 0, 20, and 500 microM of the agent for 24 h. An in situ endolabeling assay was performed to determine the index of apoptotic induction. MTT assay revealed that concentrations of 100 microM and above were cytotoxic. DNA laddering was demonstrated in agarose gel electrophoresis. TEM disclosed condensing and fragmentation of the chromatin. None of these changes were observed in the control group and the noncytotoxic dose group. The in situ endolabeling study disclosed that the apoptotic index was significantly elevated by cytotoxic doses of this agent (U373MG; control, 4.0%; 500 microM, 68.5%). These results indicated that cytotoxic concentrations of BE16627B induced apoptosis in human malignant glioma cell lines. In our previous report, this agent inhibited activity of MMP in noncytotoxic concentrations. Further study should be done to determine the pharmacological action of toxic BE16627B.
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PMID:Apoptotic induction by BE16627B on human malignant glioma cell lines by an anti-matrix metalloproteinase agent. 1460 27

Hyaluronan (HA) is a component of the brain extracellular matrix environment that is synthesized and secreted by glioma cells. The primary cell surface receptor for HA is CD44, a membrane glycoprotein that is functionally regulated by a membrane type 1 matrix metalloproteinase (MT1-MMP). Both CD44 and MT1-MMP are partially located in Triton X-100-insoluble domains, but no functional link has yet been established between them. In the present study, we studied the regulation of HA cell surface binding in U-87 glioma cells. We show that an MMP-dependent mechanism regulates the intrinsic cell surface binding of HA as ilomastat, a broad MMP inhibitor, increased HA binding to glioma cells. HA binding was also rapidly and specifically up-regulated by 3-fold by type I collagen in U-87 cells, which also induced a significant morphological reorganization associated with the activation of a latent form of MMP-2 through a MT1-MMP-mediated mechanism. Interestingly, caveolae depletion with a cell surface cholesterol-depleting agent beta-cyclodextrin triggered an additional increase (9-fold) in the binding of HA, in synergy with type I collagen. On the other hand, HA cell surface binding was diminished by the MEK inhibitor PD98059 and by the overexpression of a recombinant, wild type MT1-MMP, whereas its cytoplasmic-deleted form had no effect. Taken together, our results suggest that MT1-MMP regulates, through its cytoplasmic domain, the cell surface functions of CD44 in a collagen-rich pericellular environment. Additionally, we describe a new molecular mechanism regulating the invasive potential of glioma cells involving a MT1-MMP/CD44/caveolin interaction, which could represent a potential target for anti-cancer therapies.
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PMID:Hyaluronan cell surface binding is induced by type I collagen and regulated by caveolae in glioma cells. 1501 31

Protective antigen (PA) and lethal factor (LF) are the two components of anthrax lethal toxin. PA is responsible for interacting with cell receptors and for the subsequent translocation of LF inside the cell compartment. A re-engineered toxin comprised of PA and a fusion chimera LF/Pseudomonas exotoxin (FP59) is a promising choice for tumor cell surface targeting. We demonstrated, however, that in vitro in cell-free system and in cultured human colon carcinoma LoVo, fibrosarcoma HT1080 and glioma U251 cells membrane type-1 matrix metalloproteinase (MT1-MMP) cleaves both the PA83 precursor and the PA63 mature protein. Exhaustive MT1-MMP cleavage of PA83 in vitro generates several major degradation fragments with an N-terminus at Glu40, Leu48, and Gln512. In cultured cells, MT1-MMP-dependent cleavage releases the cell-bound PA83 and PA63 species from the cell surface. As a result, MT1-MMP expressing cells have less PA63 to internalize. In agreement, our observations demonstrate that MT1-MMP proteolysis of PA makes the MT1-MMP-expressing aggressive invasive cells resistant to the cytotoxic effect of a bipartite PA/FP59 toxin. We infer from our studies that synthetic inhibitors of MMPs are likely to increase the therapeutic anti-cancer effect of anthrax toxin. In addition, our study supports a unique role of furin in the activation of PA, thereby suggesting that furin inhibitors are the likely specific drugs for short-term therapy of anthrax infection.
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PMID:Membrane type-1 matrix metalloproteinase (MT1-MMP) protects malignant cells from tumoricidal activity of re-engineered anthrax lethal toxin. 1538 Nov 57

Migration and invasion are prerequisites for the neoplastic phenotype of malignant glioma. Ectopic expression of BCL-2 enhances migration and invasion of glioma cells and promotes their synthesis of transforming growth factor-beta2 (TGF-beta2). We here report that BCL-2-expressing cells show enhanced expression and activity of the proprotein convertase, furin, which processes metalloproteinases (MMP) and TGF-beta. Consistent with a biological role for a BCL-2-dependent increase in furin-like protease (FLP) activity, BCL-2-expressing cells exhibit enhanced MMP activity. Both a pseudosubstrate furin inhibitor, decanoyl-Arg-Val-Lys-Arg-chloromethylketone (dec-RVKR-cmk), or alpha 1-anti-trypsin Portland (PDX), a recombinant furin-inhibitory protein, suppress constitutive and BCL-2-mediated MMP activity and invasion. This inhibition is not overcome by TGF-beta or hepatocyte growth factor (HGF). A neutralizing TGF-beta antibody attenuates, but not abrogates, the invasive properties conferred by exogenous expression of BCL-2, whereas the MMP inhibitor o-phenantroline (o-PA) abolishes the pro-invasive action of BCL-2. Exogenous HGF results in enhanced, and expression of dominant-negative ezrin in reduced, FLP activity, and dec-RVKR-cmk blunts the HGF-induced expression of mature TGF-beta2. Consequently, HGF and BCL-2 family proteins use a furin-dependent pathway to promote invasion via TGF-beta and MMP in human malignant glioma cells and the pro-invasive properties of TGF-beta require furin- dependent MMP activity.
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PMID:BCL-2-induced glioma cell invasiveness depends on furin-like proteases. 1558 4

Diffuse infiltration of malignant human glioma cells into surrounding brain structures occurs through the activation of multigenic programs. We recently showed that angiopoietin-2 (Ang2) induces glioma invasion through the activation of matrix metalloprotease-2 (MMP-2). Here, we report that up-regulation of Ang2, MMP-2, membrane type 1-MMP (MT1-MMP), and laminin 5 gamma 2 (LN 5 gamma 2) in tumor cells correlates with glioma invasion. Analyses of 57 clinical human glioma biopsies of World Health Organization grade I to IV tumors displaying a distinct invasive edge and 39 glioma specimens that only contain the central region of the tumor showed that Ang2, MMP-2, MT1-MMP, and LN 5 gamma 2 were co-overexpressed in invasive areas but not in the central regions of the glioma tissues. Statistical analyses revealed a significant link between the preferential expression of these molecules and invasiveness. Protein analyses of microdissected primary glioma tissue showed up-regulation and activation of MT1-MMP and LN 5 gamma 2 at the invasive edge of the tumors, supporting this observation. Concordantly, in human U87MG glioma xenografts engineered to express Ang2, increased expression of MT1-MMP and LN 5 gamma 2, along with MMP-2 up-regulation, in actively invading glioma cells was also evident. In cell culture, stimulation of glioma cells by overexpressing Ang2 or exposure to exogenous Ang2 promoted the expression and activation of MMP-2, MT1-MMP, and LN 5 gamma 2. These results suggest that up-regulation of Ang2, MMP-2, MT1-MMP, and LN 5 gamma 2 is associated with the invasiveness displayed by human gliomas and that induction of these molecules by Ang2 may be essential for glioma invasion.
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PMID:Up-regulation of angiopoietin-2, matrix metalloprotease-2, membrane type 1 metalloprotease, and laminin 5 gamma 2 correlates with the invasiveness of human glioma. 1574 99

Glioma cell-surface binding to hyaluronan (HA), a major constituent of the brain extracellular matrix (ECM) environment, is regulated through a complex membrane type-1 matrix metalloproteinase (MT1-MMP)/CD44/caveolin interaction that takes place at the leading edges of invading cells. In the present study, intracellular transduction pathways required for the HA-mediated recognition by infiltrating glioma cells in brain was investigated. We show that the overexpression of the GTPase RhoA up-regulated MT1-MMP expression and triggered CD44 shedding from the U-87 glioma cell surface. This potential implication in cerebral metastatic processes was also observed in cells overexpressing the full-length recombinant MT1-MMP, while the overexpression of a cytoplasmic domain truncated from of MT1-MMP failed to do so. This suggests that the cytoplasmic domain of MT1-MMP transduces intracellular signaling leading to RhoA-mediated CD44 shedding. Treatment of glioma cells with the Rho-kinase (ROK) inhibitor Y27632, or with EGCg, a green tea catechin with anti-MMP and anti-angiogenesis activities, antagonized both RhoA- and MT1-MMP-induced CD44 shedding. Conversely, overexpression of recombinant ROK stimulated CD44 release. Taken together, our results suggest that RhoA/ROK intracellular signaling regulates MT1-MMP-mediated CD44 recognition of HA. These molecular processes may partly explain the diffuse brain-infiltrating character of glioma cells within the surrounding parenchyma and thus be a target for new approaches to anti-tumor therapy.
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PMID:Probing the infiltrating character of brain tumors: inhibition of RhoA/ROK-mediated CD44 cell surface shedding from glioma cells by the green tea catechin EGCg. 1599 76

Chemokines have been found to alter tumor growth and metastasis. We have described previously that a particular chemokine receptor, CXCR4, was predominantly expressed on various glioma cell lines and in resected glioblastoma specimens. Herein, we have tested the ligand of CXCR4, stromal cell derived factor-1alpha (SDF-1alpha, CXCL12), on the response of human glioma cells. We found that SDF-1alpha increased the expression of membrane type-2 matrix metalloproteinase (MT2-MMP), but not the other MT-MMPs, MMP-2 or MMP-9. The SDF-1alpha enhanced MT2-MMP expression was blocked by a CXCR4 antagonist, AMD3100. Functional invasion assays showed that SDF-1alpha stimulated glioma cells to invade through matrigel-coated chambers and this effect was inhibited in glioma cells by the stable downregulation of MT2-MMP expression using small interfering RNA (siRNA). In vivo and at asymptomatic stages following intracerebral implant of cells, mice harboring MT2-MMP siRNA downregulated clones had smaller and less invasive tumors compared with mice implanted with non-specific siRNA control cells. Analyses at symptomatic stages demonstrate that mice with MT2-MMP siRNA clones survive longer than mice harboring control cells. These results highlight MT2-MMP as an effector of CXCR4 signaling in glioma cells, and they reveal the novel role of MT2-MMP in modulating tumor activity.
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PMID:The chemokine stromal cell derived factor-1 (CXCL12) promotes glioma invasiveness through MT2-matrix metalloproteinase. 1603 74

Invasion of glioma cells involves the attachment of invading tumor cells to extracellular matrix (ECM), disruption of ECM components, and subsequent cell penetration into adjacent brain structures. Discoidin domain receptor 1 (DDR1) tyrosine kinases constitute a novel family of receptors characterized by a unique structure in the ectodomain (discoidin-I domain). These cell surface receptors bind to several collagens and facilitate cell adhesion. Little is known about DDR1 expression and function in glioblastoma multiforme. In this study we demonstrate that DDR1 is overexpressed in glioma tissues using cDNA arrays, immunohistochemistry and Western blot analysis. Functional comparison of two splice variants of DDR1 (DDR1a and DDR1b) reveal novel differences in cell based glioma models. Overexpression of either DDR1a or DDR1b caused increased cell attachment. However, glioma cells overexpressing DDR1a display enhanced invasion and migration. We also detect increased levels of matrix metalloproteinase-2 in DDR1a overexpressing cells as measured by zymography. Inhibition of MMP activity using MMP inhibitor suppressed DDR1a stimulated cell-invasion. Similarly, an antibody against DDR1 reduced DDR1a mediated invasion as well as the enhanced adhesion of DDR1a and DDR1b overexpressing cells. These results suggest that DDR1a plays a critical role in inducing tumor cell adhesion and invasion, and this invasive phenotype is caused by activation of matrix metalloproteinase-2.
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PMID:Discoidin domain receptor-1a (DDR1a) promotes glioma cell invasion and adhesion in association with matrix metalloproteinase-2. 1623 85


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