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)

We previously found the neuronal cell-type specific promoter and binding partner of the beta isoform of Ca(2+)/calmodulin-dependent protein kinase II (beta CaM kinase II) in rat brain [Donai, H., Morinaga, H., Yamauchi, T., 2001. Genomic organization and neuronal cell type specific promoter activity of beta isoform of Ca(2+)/calmodulin-dependent protein kinase II of rat brain. Mol. Brain Res. 94, 35-47]. In the present study, we purified a protein that binds specifically a promoter region of beta CaM kinase II gene from a nuclear extract of the rat cerebellum using DEAE-cellulose column chromatography, ammonium sulfate fractionation, gel filtration and polyacrylamide gel electrophoresis. The purified protein was identified as rat leucine-rich protein 157 (rLRP157) using tandem mass spectrometry. Then, we prepared its cDNA by reverse transcriptase-polymerase chain reaction (RT-PCR) from poly(A)(+)RNA of rat cerebellum. The rLRP157 cDNA was introduced into mouse neuroblastomaxrat glioma hybrid NG108-15 cells, and cells stably expressing rLRP157 (NG/LRP cells) were isolated. Binding of rLRP157 with the promoter sequence was confirmed by electrophoretic mobility shift assay using nuclear extract of NG/LRP cells. A luciferase reporter gene containing a promoter of beta CaM kinase II was transiently expressed in NG/LRP cells. Under the conditions, the promoter activity was enhanced about 2.6-fold in NG/LRP cells as compared with wild-type cells. The expression of rLRP157 mRNA was paralleled with that of beta CaM kinase II in the adult and embryo rat brain detected by in situ hybridization. Nuclear localization of rLRP157 was confirmed using GFP-rLRP157 fusion protein investigated under a confocal microscope. These results indicate that rLRP157 is one of the proteins binding to, and regulating the activity of, the promoter of beta CaM kinase II.
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PMID:Rat leucine-rich protein binds and activates the promoter of the beta isoform of Ca2+/calmodulin-dependent protein kinase II gene. 1733 62

Expression of cyclooxygenase-2 (COX-2) has been linked to many cancers and may contribute to malignant phenotypes, including enhanced proliferation, angiogenesis, and resistance to cytotoxic therapies. Malignant gliomas are highly aggressive brain tumors that display many of these characteristics. One prominent molecular abnormality discovered in these astrocytic brain tumors is alteration of epidermal growth factor (EGF) receptor (EGFR) through gene amplification and/or mutation resulting in excessive signaling from this receptor. We found that EGF-mediated stimulation of EGFR tyrosine kinase in human glioma cell lines induces expression of both COX-2 mRNA and protein. The p38 mitogen-activated protein kinase (p38-MAPK) pathway was a strong downstream factor in this activation with inhibition of this pathway leading to strong suppression of COX-2 induction. The p38-MAPK pathway can activate the Sp1/Sp3 transcription factors and this seems necessary for EGFR-dependent transactivation of the COX-2 promoter. Analysis of COX-2 promoter/luciferase constructs revealed that transcriptional activation of the COX-2 promoter by EGFR requires the Sp1 binding site located at -245/-240. Furthermore, Sp1/Sp3 binding to this site in the promoter is enhanced by EGFR activation both in vitro and in vivo. Enhanced DNA binding by Sp1/Sp3 requires p38-MAPK activity and correlates with increased phosphorylation of the Sp1 transcription factor. Thus, EGFR activation in malignant gliomas can transcriptionally activate COX-2 expression in a process that requires p38-MAPK and Sp1/Sp3. Finally, treatment of glioma cell lines with prostaglandin E2, the predominant product of COX-2 activity, results in increased vascular endothelial growth factor expression, thus potentially linking elevations in COX-2 expression with tumor angiogenesis in malignant gliomas.
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PMID:EGFR activation results in enhanced cyclooxygenase-2 expression through p38 mitogen-activated protein kinase-dependent activation of the Sp1/Sp3 transcription factors in human gliomas. 1761 68

Many altered pathways in cancer cells depend on growth factor receptors. In primary malignant gliomas, the amplification/alteration of the epidermal growth factor receptor (EGFR) has been shown to play a significant role in enhancing glioma burden. In an effort to dissect the role of EGFR expression in glioma progression in vivo and evaluate targeted therapies for gliomas, we have genetically engineered glioma cells to visualize the dynamics of EGFR and targeted therapies in real time in vivo. Using engineered lentiviral vectors bearing fusions between EGFR and its exon 2 to 7 deleted variant (EGFRvIII) with green fluorescent protein (GFP) and Renilla luciferase (Rluc), we show that there is a direct correlation between EGFR expression and glioma cell proliferation in the initial stages of glioma progression. To monitor and evaluate EGFR-targeted therapies, we have engineered (a) short hairpin RNAs (shRNA) and (b) clinically used monoclonal antibody, cetuximab. Using EGFR-GFP-Rluc/firefly luciferase (Fluc)-DsRed2 glioma model, we show that both shRNAs and cetuximab result in a considerable reduction in glioma cell proliferation in culture and glioma burden in vivo that can be monitored in real time at a cellular resolution. This study serves as a template to follow the role of growth factor receptor expression in tumor progression and to image therapeutic efficacy of targeted therapies in cancer.
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PMID:Visualizing the dynamics of EGFR activity and antiglioma therapies in vivo. 1767 Dec 3

Targeting gene expression to cancer cells remains a challenge for the development of gene and viral therapy for gliomas. Recent studies have highlighted transcriptional targeting as one of the possible solutions to overcome this limitation. In this context, melanoma associated antigens (MAAs) are usually over-expressed in brain tumors in comparison to normal brain tissue. For this reason, we investigated the use of the tyrosinase promoter as a transcriptional element to target oncolytic therapy for gliomas. Tyrosinase mRNA expression was evaluated by qRT-PCR in normal human brain tissue as well as in human glioma specimens. We found that this gene was significantly over-expressed in glioma cell lines and in primary glioma samples. Tyrosinase expression correlated with the grade of the tumor (p-value range: 0.05-0.001). Furthermore, transfection of several cell cultures with human and mouse tyrosinase promoters driving a luciferase reporter gene confirmed the activity of this promoter in mouse and human cells. To evaluate whether tyrosinase-activated conditionally replicative adenoviruses (CRAds) could induce toxicity in glioma cells, two vectors (Ad h/m and Ad24TYR) were tested in a mouse glioma model. C57BL/6 mice underwent intracranial injection of tumor cell line GL261. Survival was used to evaluate efficacy of the tested vectors. Mice receiving 1 x 10(9) MOI of Ad h/m and Ad24TYR following intracranial tumor implants had a median survival of 46+/-3 days (p<0.05); in contrast, those treated with medium had a median survival of 31+/-2 days. These results suggest that injection of tyrosinase CRAds leads to prolongation of survival in mice with experimental brain tumors. The tyrosinase promoter stands as a proof of principle of the potential use of MAA over-expression patterns for targeting novel anti-glioma therapies.
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PMID:An oncolytic adenoviral vector carrying the tyrosinase promoter for glioma gene therapy. 1791 45

Microglia are the primary central nervous system immune effector cells. Microglial activation is linked to interactions with extracellular cytokines and the extracellular matrix (ECM). Astrocytomas are characterized by their diffuse nature, which is regulated by insoluble ECM components produced by the tumor cells that are largely absent from normal central nervous system tissue. The present study examined the influence of astrocytoma (C6 rat glioma) insoluble matrix components on interferon-gamma (IFN-gamma)-mediated inducible nitric-oxide synthase (iNOS) induction in microglial cells. We found that IFN-gamma-stimulated iNOS induction and nitric oxide release was greater in microglia cultured on C6 glioma cell-derived matrices compared with microglia cultured on primary rat astrocyte-derived matrices. Culture of microglia on C6 glioma cell-derived matrices also led to activation of STAT1, augmentation of IFN-gamma-induced STAT-3 activation, and an increase in IFN-gamma-activated site (GAS)-luciferase reporter activity. In addition, culture of microglia on C6 glioma cell-derived matrices activated NF-kappaB DNA binding activity and transcriptional activity. The results suggest that insoluble matrix components derived from malignant glioma cells can regulate microglia activation. These factors may include ECM components, such as fibronectin, collagen, laminin, vitronectin, and other nondiffusible compounds, and laminin seems to a critical regulator of this process. Microglia activation and subsequent brain inflammation may influence tumor growth, treatment, and metastasis. Better understanding of the regulation of microglial activation by astrocytoma-derived insoluble matrix components may be important in the development of immune-based treatment strategies against malignant brain tumors.
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PMID:C6 glioma cell insoluble matrix components enhance interferon-gamma-stimulated inducible nitric-oxide synthase/nitric oxide production in BV2 microglial cells. 1798 10

Recently, the changes of neuronal and glial plasticity related gene expression following the increase of monoamine are suggested to be important for the therapeutic effect of antidepressants. We previously showed that antidepressants increased glial cell line-derived neurotrophic factor (GDNF) expression, which was dependent on acute activation of protein tyrosine kinase (PTK) and extracellular signal-regulated kinase (ERK) in rat C6 glioma cells (C6 cells) and normal human astrocytes (NHA). Transcription of many genes including GDNF is directed by the cAMP responsive element (CRE) and its cognate transcription factor CRE binding protein (CREB). In this study, we showed that amitriptyline, a tricyclic antidepressant, acutely increased phosphorylation of CREB, without altering the level of total CREB in C6 cells as well as in NHA. In contrast, acute amitriptyline treatment did not affect phosphorylation of CREB in SH-SY5Y cells, a human neuroblastoma cell line. Different classes of antidepressants as well as amitriptyline acutely increased phosphorylation of CREB, but haloperidol and diazepam did not. The amitriptyline-induced phosphorylation of CREB was completely blocked by U0126 [a mitogen-activated protein (MAP) kinase kinase 1 inhibitor] and genistein (a PTK inhibitor), but not by inhibitors of protein kinase A, p38 MAP kinase, or Ca(2+)/calmodulin-dependent kinase. Amitriptyline treatment also increased the expression of luciferase reporter gene regulated by CRE elements. The amitriptyline-induced luciferase activity was completely inhibited by U0126 in the same as phosphorylation of CREB. These results suggest that antidepressants acutely increase CREB activity in PTK and ERK-dependent manners, which might contribute to gene expression including GDNF in glial cells.
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PMID:Antidepressants induce acute CREB phosphorylation and CRE-mediated gene expression in glial cells: a possible contribution to GDNF production. 1823 63

Abstract Glioblastoma multiforme (GBM), the highest-grade glioma, is the most frequent tumour of the brain with a very poor prognosis and limited therapeutic options. Although little is known about the molecular mechanisms that underlie glioblastoma formation, a number of signal transduction routes, such as the Notch and Ras signalling pathways, seem to play an important role in the formation of GBM. In the present study, we show by in situ hybridization on primary tumour material that the transcription factor HEY1, a target of the Notch signalling pathway, is specifically up-regulated in glioma and that expression of HEY1 in GBM correlates with tumour-grade and survival. In addition, we show by chromatin immunoprecipitations, luciferase assays and Northern blot experiments that HEY1 is a bona fide target of the E2F family of transcription factors, connecting the Ras and Notch signalling pathways. Finally, we show that ectopic expression of HEY1 induces cell proliferation in neural stem cells, while depletion of HEY1 by RNA interference reduces proliferation of glioblastoma cells in tissue culture. Together, these data imply a role for HEY1 in the progression of GBM, and therefore we propose that HEY1 may be a therapeutic target for glioblastoma patients. Moreover, HEY1 may represent a molecular marker to distinguish GBM patients with a longer survival prognosis from those at high risk.
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PMID:A role for the transcription factor HEY1 in glioblastoma. 1836 32

Transplantation of genetically engineered cells into the CNS offers immense potential for the treatment of several neurological disorders. Monitoring expression levels of transgenes and following changes in cell function and distribution over time is critical in assessing therapeutic efficacy of such cells in vivo. We have engineered lentiviral vectors bearing fusions between different combinations of fluorescent and bioluminescent marker proteins and used bioluminescence imaging and intravital-scanning microscopy in real time to study the fate of human neural stem cells (hNSCs) at a cellular resolution in glioma-bearing brains in vivo. Using Renilla luciferase (Rluc)-DsRed2 or GFP-Rluc-expressing malignant human glioma model, transduced hNSCs were shown to migrate extensively toward gliomas, with hNSCs populating gliomas at 10 d after transplantation. Furthermore, transduced hNSCs survived longer in mice with gliomas than in normal brain, but did not modulate glioma progression in vivo. These studies demonstrate the utility of bimodal viral vectors and real-time imaging in evaluating fate of NSCs in diseased models and thus provide a platform for accelerating cell-based therapies for CNS disorders.
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PMID:Bimodal viral vectors and in vivo imaging reveal the fate of human neural stem cells in experimental glioma model. 1843 19

Lysophosphatidylserine (LPS) was found to stimulate intracellular calcium increase in U87 human glioma cells. LPS also stimulated chemotactic migration of U87 human glioma cells, which was completely inhibited by pertussis toxin (PTX). Moreover, LPS was also found to stimulate ERK, p38 MAPK, JNK, and Akt activities in U87 cells. We observed that LPS-induced U87 chemotaxis was mediated by PI3K, p38 MAPK, and JNK. LPS-induced chemotactic migration in U87 cells was inhibited by Ki16425, an LPA(1/3) receptor-selective antagonist, which suggested that the Ki16425-sensitive G-protein coupled receptor (GPCR) played a role in this process. Moreover, U87 cells were found to uniquely express LPA(1) but not LPA(2-5). In addition, LPS failed to stimulate the NF-kappaB-driven luciferase activity in exogenously LPA(1)-transfected HepG2 cells. Taken together, we propose that LPS stimulates GPCR, which is in contrast to the well-known LPA receptors, thus resulting in the chemotactic migration in U87 human glioma cells.
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PMID:Lysophosphatidylserine stimulates chemotactic migration in U87 human glioma cells. 1861 30

The value of bioluminescence imaging (BLI) for experimental cancer models has become firmly established. We applied BLI to the GL261 glioma model in the context of dendritic cell (DC) immunotherapy. Initial validation revealed robust linear correlations between in vivo, ex vivo and in vitro luciferase activity measurements. Ex vivo BLI demonstrated midline crossing and leakage of tumor cells. Orthotopically challenged mice followed with BLI showed an initial adaptation phase, after which imaging data correlated linearly with stereologically determined tumor dimensions. Transition from healthy to moribund state corresponded with an increasing in vivo flux but the onset of neurological deficit was clearly delayed compared to the onset of in vivo flux increase. BLI was implemented in prophylactic immunotherapy and imaging data were prognostic for therapy outcome. Three distinct response patterns were detected. Our data underscore the feasibility of in vivo BLI in an experimental immunotherapeutic setting in the GL261 glioma model.
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PMID:In vivo bioluminescence imaging in an experimental mouse model for dendritic cell based immunotherapy against malignant glioma. 1878 61


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