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)

Future success using chemotherapy against human gliomas may result from exploiting unique molecular vulnerabilities of these tumors. Chemotherapy frequently results in DNA damage. When such damage is sensed by the cell, programmed cell death, or apoptosis, may be initiated. However, chemotherapy-induced DNA damage may activate nuclear factor kappa B (NF-kappaB) and block apoptosis. We inhibited NF-kappaB using a gene therapy approach to determine whether this would render human glioma cells more susceptible to chemotherapy. U87 and U251 glioma cell lines were infected with either treatment adenovirus containing the gene for a mutant non-degradable form of IkappaBalpha, which is an inhibitor of NF-kappaB nuclear translocation, or empty control virus. Following viral infection, cells were treated either with BCNU, carboplatin, tumor necrosis factor alpha (TNF-alpha), or SN-38. Chemotherapy resulted in a marked increase in active intranuclear NF-kappaB. This response was greatly decreased by insertion of the mutant repressor gene. Similarly, a significant increase in cell killing by all chemotherapy age was demonstrated following infection with treatment virus. Expression of the mutant repressor gene also resulted in increased apoptosis by TUNEL assay following chemotherapy. Numerous genes are responsible for glioma chemoresistance. DNA damage by chemotherapy may induce the antiapoptotic factor NF-kappaB and prevent programmed cell death. Insertion of a mutant inhibitor of NF-kappaB strips cells of this antiapoptotic defense and renders them more susceptible to killing by chemotherapy via increased apoptosis.
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PMID:Potentiation of chemotherapeutic agents following antagonism of nuclear factor kappa B in human gliomas. 1267 10

The extremely poor prognosis of malignant gliomas requires the investigation of other than standard therapies, i.e., the application of oncolytic viruses. In our study, we evaluated the effects of the oncosuppressive parvovirus H-1 on different established glioblastoma cell lines of rat and human origin and on short-term/low-passage cultures of human glioblastoma cells. We observed an efficient and dose-dependent killing of all glioma cell cultures at low multiplicities of infectious particles (MOI) per cell. Southern blot analysis of viral DNA amplification, RT-PCR analysis of viral RNA expression and Western blot analysis of the expression of viral structural (VP-1/VP-2) and nonstructural (NS-1) proteins demonstrated the biosynthesis of these viral macromolecular components in all of the cultures. Moreover, all the glioma cells were proficient for the production of infectious H-1 virus particles. The amount of virus production differed between a several fold increase of the input virus titer in most of the short-term/low-passage cultures up to 1,000-fold in one short-term glioma and in the rat cells. Glioma cells lines and, more importantly, short-term/low-passage cultures of human glioblastomas were found to be highly susceptible target cells for H-1 virus mediated cytotoxicity. The formation of fully infectious progeny particles in infected glioma cells offers the chance for the induction of secondary rounds of infection resulting in an advanced cytotoxic effect. These advantageous characteristics of H-1 virus infection of glioma cells, combined with the known low toxicity of H-1 virus in nontransformed cells, make parvovirus H-1 a promising candidate for oncolytic glioma therapy.
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PMID:Parvovirus H-1 infection of human glioma cells leads to complete viral replication and efficient cell killing. 1473 71

Primary central nervous system lymphoma most often presents as a solitary, isolated lesion in immunocompetent patients. Rarely, the disease presents as a diffuse, infiltrating condition without formation of a cohesive mass, a pattern called lymphomatosis cerebri. We present 3 immunocompetent individuals who developed rapidly progressive dementia. Magnetic resonance imaging features mimicked other disorders of white matter and prompted preoperative diagnoses of Binswanger's disease (subcortical ischemic vascular dementia), unknown leukoencephalopathy, viral infection, or infiltrating glioma. Neuropathologic examination at biopsy (Poon T, Matoso I, Tchertkoff V, Weitzner I Jr, Gade M. CT features of primary cerebral lymphoma in AIDS and non-AIDS patients. J Comput Assist Tomogr . 1989;13:6-9) and autopsy (Schwaighofer BW, Hesselink JR, Press GA, Wolf RL, Healy ME, Berthoty DP. Primary intracranial CNS lymphoma: MR manifestations. Am J Neuroradiol . 1993;10:725-9) demonstrated nonnecrotic, diffusely infiltrating, large-cell B-cell lymphoma of white matter, with relative sparing of gray matter, and without significant leptomeningeal involvement or bulky periventricular disease at autopsy. Microglial and astrocytic reactions, but only subtle myelin pallor, were evident as individual tumor cells permeated the entire brain and spinal cord, albeit with considerable variation in cell density. Individual tumor cells could be identified from the optic nerve to spinal cord, documenting the "whole-brain" nature of the disease. CD20 immunostaining was necessary to fully appreciate the extent of individual lymphoma cell percolation through the white matter. The neurobehavioral deficits manifested by these patients demonstrate that lymphomatosis cerebri is an additional neoplastic cause of white matter dementia and can be added to the growing list of disorders responsible for this syndrome.
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PMID:Lymphomatosis cerebri as a cause of white matter dementia. 1579 73

We analyzed the response of human glioma cells to West Nile virus infection by investigating host transcriptional changes. Changes in expression of 23 genes showed similarities to those in other neurodegenerative diseases. These changes may be useful as potential biomarkers and elucidate novel mechanisms behind the neuropathology of infection with this virus.
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PMID:Molecular mechanisms of West Nile virus pathogenesis in brain cell. 1582 8

Research on HIV vaccines, as well as studies on HIV pathogenesis in human and SIV in the macaque model, require the availability of simple and standardized assays for quantification of neutralizing antibodies to primary virus isolates. We have recently developed and standardized assays using human cell lines engineered to express CD4 and co-receptors for HIV and SIV entry. One cell line originated from a glioma (U87) and the other from an osteosarcoma (HOS). Both cell lines and their derivatives form monolayer cultures, a prerequisite for counting plaques. HIV-infected U87.CD4-CCR5 or -CXCR4 cells form syncytia, that is, plaques that can be stained with hematoxylin and enumerated by light microscopy. In addition to CD4 and co-receptors (most often used CCR5 and CXCR6 by SIV), GHOST(3) cells have been engineered to express the green fluorescent protein following virus infection. Infected cells show green fluorescence and can be enumerated by fluorescence microscopy. Neutralization is determined by the ability of a serum to reduce the number of plaque-forming units (PFU) relative to controls exposed to medium or negative serum. Both assays are run in microtiter format and neutralization is evaluated after 3 d. Intra-assay variation has been used for estimation of the cutoff for neutralization. Testing 15 serum-virus combinations in the U87.CD4 assay and four serum-virus combinations in the GHOST(3) assay revealed that standard deviation of differences ranged from 9.1% to 9.9% in the two assays. This allowed the use of a cutoff >3 SD; that is, 30% neutralization. Virus titration experiments showed that neutralization results were dependent on virus dose and therefore the neutralization assays should be performed with a virus dose of 10-100 PFU/well. The assays have high specificity and reproducibility, and are simple and sensitive high-throughput assays.
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PMID:Plaque-reduction assays for human and simian immunodeficiency virus neutralization. 1606 83

Amphotropic retroviruses with modified envelope displaying single-chain antibody fragment (scFv) directed against the c-Met receptor were recently generated and found to efficiently and selectively deliver genes into hepatocarcinoma cells. A large proportion of human gliomas also frequently overexpresses c-Met. We therefore explored the possibility of infecting glioma cells using such retroviruses bearing an scFv directed against c-Met. In one construct, a urokinase (uPA) cleavage site was inserted between the scFv and the envelope. We assessed the transduction by these chimeric viruses of a panel of seven human glioma cell lines that we characterized for their c-Met and uPA levels. We found that abundance of the c-Met receptor and viral infection were inversely correlated if we used the retrovirus displaying scFv directed against c-Met, suggesting that the chimeric virus binds preferentially to the c-Met receptor, resulting in virus sequestration. Addition of the uPA site between the scFv moiety and the envelope restored the infectivity of the virus, consistent with a "two-step" infection process: (1) virus binding to the c-Met receptor, (2) cleavage of the scFv moiety by uPA, enabling the virus to dissociate from c-Met and entry into the cells via the Pit-2 receptor. Our study has significant implications for the design of targeting strategies for gliomas expressing high levels of c-Met.
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PMID:Targeting of c-Met and urokinase expressing human glioma cell lines by retrovirus vector displaying single-chain variable fragment antibody. 1608 94

Myxoma virus, a poxvirus previously considered rabbit specific, can replicate productively in a variety of human tumor cells in culture. The purpose of this study was to determine if there was efficacy or toxicities of this oncolytic virus against experimental models of human malignant gliomas in vitro, in vivo, and ex vivo in malignant glioma specimens. In vitro, the majority of glioma cell lines tested (7 of 8, 87.5%) were fully permissive for myxoma virus replication and killed by infection. In vivo, intracerebral (i.c.) myxoma virus inoculation was well tolerated and produced only minimal focal inflammatory changes at the site of viral inoculation. U87 and U251 orthotopic xenograft models were used to assess myxoma virus efficacy in vivo. A single intratumoral injection of myxoma virus dramatically prolonged median survival compared with treatment with UV-inactivated myxoma virus. Median survival was not reached in myxoma virus-treated groups versus 47.3 days (U87; P = 0.0002) and 50.7 days (U251; P = 0.0027) in UV-inactivated myxoma virus-treated groups. Most myxoma virus-treated animals (12 of 13, 92%) were alive and apparently "cured" when the experiment was finished (>130 days). Interestingly, we found a selective and long-lived myxoma virus infection in gliomas in vivo. This is the first demonstration of the oncolytic activity of myxoma virus in vivo. The nonpathogenic nature of myxoma virus outside of the rabbit host, its capacity to be genetically modified, its ability to produce a long-lived infection in human tumor cells, and the lack of preexisting antibodies in the human population suggest that myxoma virus may be an attractive oncolytic agent against human malignant glioma.
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PMID:Myxoma virus is a novel oncolytic virus with significant antitumor activity against experimental human gliomas. 1626 23

Genetically engineered herpes simplex virus ICP34.5 null mutants replicate only in dividing cells and have shown potential for the treatment of malignant disease, including glioma. Phase I trials have demonstrated the safety of these viruses in various clinical settings but it is envisaged that for full efficacy they will be used in combination with other therapeutic modalities. To enhance virus-induced tumour cytotoxicity, we have engineered an ICP34.5 null mutant (HSV1716) of HSV1 which expresses the noradrenaline transporter gene (NAT). This virus is designated HSV1716/NAT. We have shown previously that introduction of the NAT gene into a range of tumour cells, via plasmid-mediated transfection, conferred the capacity for active uptake of the radiopharmaceutical [131I]MIBG and resulted in dose-dependent toxicity. In this study, combination therapy utilising HSV1716/NAT and [131I]MIBG was assessed in vitro by the MTT assay. We demonstrate that the NAT gene, introduced by HSV1716/NAT into cultured glioma cells, was expressed 1 h after viral infection, enabling active uptake of [131I]MIBG. The combination of viral oncolysis and induced radiopharmaceutical uptake resulted in significantly enhanced cytotoxicity compared to either agent alone and the response was dose- and time-dependent. These studies show that the combination of oncolytic HSV therapy with targeted radiotherapy has the potential for effective tumour cell kill and warrants further investigation as a treatment for malignant glioma.
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PMID:Assessment in vitro of a novel therapeutic strategy for glioma, combining herpes simplex virus HSV1716-mediated oncolysis with gene transfer and targeted radiotherapy. 1678 26

Measles virus (MV) has shown promise as an oncolytic virus in the treatment of different tumor models for human B-cell lymphoma, multiple myeloma, ovarian cancer, and glioma. We have shown that, in a phase I clinical trial, MV vaccine induces tumor regression in cutaneous T-cell lymphoma (CTCL) patients. Here, we investigated in detail, the effect of recombinant MV (rMV) vaccine strain in CTCL cell cultures, and in vivo in established CTCL xenografts in nude mice. The susceptibility of three CTCL cell lines, originating from patients, to rMV was tested by determination of cell surface expression of MV receptors. All cell lines expressed the receptors CD150 and CD46 and were easily infected by rMV and induced complete cell lysis. The cytoreductive activity was apparent in cells forming aggregates, indicating a cell-to-cell spread of MV and cytolysis owing to virus infection. Intratumoral (i.t.) injection of rMV, expressing enhanced green fluorescent protein induced complete regression of large established human CTCL tumors in nude mice, whereas tumors with control treatment progressed exponentially. Immunohistochemical analysis of tumor biopsies, after i.t. treatment, for MV-NP protein complex demonstrated replication of MV within the tumors. The data demonstrate the potential of MV as a therapeutic agent against CTCL.
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PMID:Recombinant measles virus induces cytolysis of cutaneous T-cell lymphoma in vitro and in vivo. 1704 18

The eradication of brain tumor stem cells is essential for long-term brain tumor remission after treatment. In this study, we examined the therapeutic potential of an oncolytic adenovirus, Delta-24-RGD, targeted to the abnormal p16INK4/Rb pathway in brain tumor stem cells. Four brain tumor stem cell lines from surgical glioblastoma specimens expressed high levels of adenoviral receptors and allowed for efficient viral infection, replication, and oncolysis in an Rb-dependent manner. Delta-24-RGD induced autophagic cell death, as indicated by accumulation of Atg5 and LC3-II protein and autophagic vacuoles. Treatment of xenografts derived from brain tumor stem cells with Delta-24-RGD statistically significantly improved the survival of glioma-bearing mice (means: 38.5 versus 66.3 days, difference = 27.8 days, 95% confidence interval = 19.5 to 35.9 days, P <.001). Analyses of treated tumors showed that Atg5 expression colocalized with viral fiber protein and delineated a wave front of autophagic cells that circumscribed areas of virally induced necrosis. Our results show for the first time that brain tumor stem cells are susceptible to adenovirus-mediated cell death via autophagy in vitro and in vivo.
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PMID:Examination of the therapeutic potential of Delta-24-RGD in brain tumor stem cells: role of autophagic cell death. 1784 77


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