Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017636 (glioblastoma)
 18,345 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We used a glioblastoma multiform (GBM) cell line to study the mechanism of cellular regulation of nitric oxide (NO) production. Our experiments indicate a confluent monolayer of GBM cells to release NO as measured through its oxidized NO2 form which gradually accumulates and reaches a peak by 7 to 10 days of culture. the addition of the L-arginine analogs L-NG-monomethyl-L-arginine and L-N omega-nitro-L-arginine and dexamethasone to the GBM cultures caused a substantial inhibition of NO production. The addition of monoclonal antibodies against IL-1 and TNF alpha to the cultures resulted in an inhibition of NO production, whereas the addition of anti-TGF beta monoclonal antibodies resulted in an increase in NO production. These findings suggest the presence of an autocrine regulatory mechanism for NO production in some tumor cell lines.
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PMID:Autocrine regulation of the production of the gaseous messenger nitric oxide in a glioblastoma cell line. 826 90

IFN-gamma induces the production of N-formyl-kynurenine from L-tryptophan in various cell types by the induction of the enzyme indoleamine 2,3-dioxygenase (IDO). The IFN-gamma induced IDO activity in the glioblastoma cell line 86HG39 and cells of clone 2D9 derived from this cell line was found to be greater than that in Hela cells and U373MG cells. Consequently 2D9 cells were used in all subsequent experiments. The determination of kynurenine in the supernatant of IFN-gamma activated cells was performed photometrically using a microplate reader. It was found that the amount of kynurenine produced was directly proportional to the amount of IFN-gamma used to activate cells. The detection limit for IFN-gamma of this assay was 20 U/ml. The induction of L-tryptophan degradation was specific for IFN-gamma since neither IFN-alpha, IFN-beta, IL-1, IL-2, IL-6, GM-CSF nor TNF alpha induced the production of detectable amounts of kynurenine by 86HG39 and 2D9 cells. Furthermore, a mab directed against IFN-gamma was able to completely block the IFN-gamma induced IDO activation. This bioassay was used to determine the IFN-gamma content of supernatants harvested from toxoplasma antigen specific human T cell lines and clones. This assay gave reproducible results which correlated well with the IFN-gamma content detected in the same samples using a commercially available ELISA kit. Furthermore in the case of T cell supernatant stimulated 2D9 cells a mab directed against IFN-gamma was able to completely block IDO induction. We conclude that the measurement of kynurenine production induced by IFN-gamma can be used to determinate IFN-gamma content. This is a simple bioassay which can be performed with standard laboratory equipment.
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PMID:A new, simple, bioassay for human IFN-gamma. 828 93

As part of continuing studies to investigate the possible regulatory effects of cytokines on malignant astrocytes, we investigated the effects of interleukin-4 (IL-4) alone and in combination with tumor necrosis factor-alpha (TNF alpha) and/or interferon-gamma (IFN gamma) on the cell growth and major histocompatibility complex (MHC) antigen expression of a cloned human glioblastoma cell line (9C). The 9C cells were treated with IL-4 alone or in combination with TNF alpha and/or IFN gamma and were examined for proliferation by crystal violet assay and for Class II MHC antigen by flow cytometry. Results indicated that IL-4 alone did not affect 9C proliferation. In combination with TNF alpha or IFN gamma, however, IL-4 significantly and dose-dependently inhibited cell growth. As previous reports have shown, TNF alpha combined with IFN gamma exerted an additive growth suppressive effect on glioblastoma cells, probably by enhancing TNF receptor expression. This additive effect of TNF alpha and IFN gamma was further enhanced by IL-4. In contrast, IL-4 did not modulate expression of Class II MHC antigen on 9C cells, even in combination with IFN gamma, which predictably enhanced this antigen. These results suggest that IL-4 is capable of modulating glioblastoma growth only in the presence of other cytokines, such as TNF alpha and/or IFN gamma. Further, the effect of IL-4 on glioblastoma proliferation is selective and independent of the mechanisms involved in regulating MHC antigen expression.
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PMID:Modulation of proliferation and antigen expression of a cloned human glioblastoma by interleukin-4 alone and in combination with tumor necrosis factor-alpha and/or interferon-gamma. 841 82

Group B streptococci are the most important bacteria inducing neonatal septicemia and meningitis. The aim of this study was to assess the role of IFNgamma in the induction of anti-microbial effector mechanisms in human brain tumor cells. Different human glioblastoma/astrocytoma cell lines, stimulated with IFNgamma, restricted the growth of group B streptococci. In addition, we found that TNF alpha is able to enhance the IFNgamma-mediated anti-microbial effect. In contrast to group B streptococci, other bacteria which are also capable of inducing meningitis, like E. coli and all but one of the tested Streptococcus pneumoniae strains, were not influenced by the IFNgamma treated cells. We found that the IFNgamma or the IFNgamma/TNF alpha induced activation of indoleamine 2,3-dioxygenase is responsible for the inhibition of streptococcal growth, since the addition of supplemental L-tryptophan completely blocks the IFNgamma induced bacteriostasis.
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PMID:Inhibition of group B streptococcal growth by IFN gamma-activated human glioblastoma cells. 972 42

We present our experience with a combination chemotherapy regimen consisting of ranimustine (MCNU) and recombinant human mutant tumor necrosis factor-alpha (TNF-SAM2) for malignant astrocytomas. The initial regimens were prescribed as adjuvant therapy in conjunction with radiotherapy following standard surgical treatment. Newly diagnosed patients were treated with up to four cycles of this regimen (TNF-SAM2, MCNU, and radiotherapy: TMR group). Seventeen patients (11 men and 6 women) aged 24 to 68 years (median 54.6 years) were eligible and evaluated for response and toxicity. The estimated median survival time was 354 weeks with anaplastic astrocytomas, and 76 weeks with glioblastomas. One- and 2-year survival rates were 100% and 100% with anaplastic astrocytomas, and 69.2% and 29.7% with glioblastomas. Grade 3 and 4 hematological toxicities were not experienced. None of the patients experienced a treatment delay due to toxicity. All other acute toxicities were anticipated and manageable. Twenty three patients (11 men and 12 women) aged 22 to 66 years (median 50.7 years) were evaluated as a historical control of patients who received chemotherapy with MCNU alone in conjunction with radiotherapy following standard surgical treatment (MCNU and radiotherapy: MR group). The estimated median survival time was 205 weeks with anaplastic astrocytomas, and 62 weeks with glioblastomas. One- and 2-year survival rates were 88.9% and 66.7% with anaplastic astrocytomas, and 71.4% and 7.1% with glioblastomas in this group. There were no significant differences in survival rates between patients in the TMR and MR groups with either anaplastic astrocytoma or glioblastoma. However, despite the small number of patients, those with anaplastic astrocytoma in the TMR group tended to survive longer than those in the MR group. These results suggest that combined chemotherapy with mutant TNF-alpha may benefit those with anaplastic astrocytoma, and thus warrants further evaluation. On the other hand, the lack of activity does not warrant any further study of this schedule of TNF-SAM2 for the treatment of glioblastoma.
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PMID:Treatment of malignant astrocytomas with recombinant mutant human tumor necrosis factor-alpha (TNF-SAM2). 985 11

Glioblastomas are particularly resistant to classical antitumor treatments. Retinoids, which proved effective in the treatment of promyelocytic leukemia, have been used for clinical assays on glioma tumors with only moderate effects; however in some cases they were active in combination with another therapy. These observations prompted us to analyse the efficacy of combining retinoic acid (RA) with a cytokine on a clonal human glioma cell line. On GL-15 cells, RA and tumor necrosis factor alpha (TNFalpha) both reduced the glial fibrillary acidic protein level and DNA synthesis and induced apoptotic pathways, but they were significantly more effective when used together. The up-regulation of the p55 TNF receptors observed during RA exposure might explain this cooperative effect.
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PMID:Effects of retinoic acid and tumor necrosis factor alpha on GL-15 glioblastoma cells. 1067 92

We present our experience with a combination chemotherapy regimen consisting of ranimustine (MCNU) and recombinant human mutant tumor necrosis factor-alpha (TNF-SAM2) for malignant astrocytomas. We also investigated the expression of nuclear factor-kappa B (NF-kappa B), tumor necrosis factor receptor type 1 (TNFR1), and c-Myc in human astrocytoma tissues in vivo in patients treated with TNF-SAM2 by RT-PCR and immunohistochemical analysis to examine whether there is any correlation between the prognosis of these patients after TNF-SAM2 treatment and the expression of these factors. The initial regimens were prescribed as adjuvant therapy in conjunction with radiotherapy following standard surgical treatment. Newly diagnosed patients were treated with up to four cycles of this regimen (TNF-SAM2, MCNU, and radiotherapy: TMR group). Four patients with anaplastic astrocytomas and 13 patients with glioblastomas (11 men and 6 women) aged 24 to 68 years (median 55.7 years) were eligible and evaluated for response and toxicity. The estimated median survival time was 354 weeks with anaplastic astrocytomas, and 79 +/- 10.8 weeks with glioblastomas. One- and 2-year survival rates were 100% and 100% with anaplastic astrocytomas, and 69.2% and 30.8% with glioblastomas. Grade 3 and 4 hematological toxicities were not experienced. None of the patients experienced a treatment delay due to toxicity. All other acute toxicities were anticipated and manageable. Two of the 4 patients with anaplastic astrocytomas were positive for the expression of NF-kappa B, TNFRl and c-Myc. The expression of NF-kappa B, TNFR1 and c-Myc was investigated in 10 of the 13 patients with glioblastoma, and c-Myc, TNFRl and NF-kappa B were detected in 9, 7, and 8 of these 10 patients' surgical specimens, respectively. Despite the small number of patients, these clinical results suggest that combined chemotherapy with mutant TNF-alpha (TNF-SAM2) was safe and well tolerated, and may confer a survival benefit for patients with malignant astrocytomas in comparison to our historical controls. Its effectiveness as an adjuvant therapy deserves a properly stratified randomized trial. Although there was no significant correlation between the efficacy of TNF-SAM2 treatment and the expression of NF-kappa B, our results suggest that the constitutive activation of NF-kappa B subunits in malignant astrocytomas, especially in glioblastoma, could be associated with resistance to TNF-alpha immunotherapy. These results could offer new insight to help establish a new chemotherapeutic strategy for malignant astrocytomas.
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PMID:Correlation of the expression of nuclear factor-kappa B, tumor necrosis factor receptor type 1 (TNFR 1) and c-Myc with the clinical course in the treatment of malignant astrocytomas with recombinant mutant human tumor necrosis factor-alpha (TNF-SAM2). 1076 4

Experiments were carried out in a nude mouse model of human glioblastoma to determine whether gamma-knife radiosurgery combined with herpes simplex virus thymidine kinase (tk) suicide gene therapy and tumor necrosis factor alpha (TNFalpha) gene transfer provided an improved multimodality treatment of this disease. Animals were inoculated intracerebrally with 2 x 10(5) U-87MG human glioblastoma cells to establish brain tumors. At 3 days postinoculation, the tumor region was injected with 2 x 10(6) infectious particles of highly defective herpes simplex viral vectors expressing the viral tk gene with the kinetics of a viral immediate early gene either alone (T.1) or together with TNF alpha (TH:TNF). Subgroups of animals were given daily intraperitoneal injections of ganciclovir (GCV) for 10 days and/or subjected to gamma-knife radiosurgery on the fifth day post tumor-cell implantation. Comparisons of animal survival showed that the TH:TNF vector in combination with radiosurgery and GCV administration provided the most effective therapy; eight of nine animals survived for 75 days compared to four of eight using the next best protocol. These findings suggest that gene therapy in combination with more conventional therapeutic methods may provide an improved strategy for extending the life expectancy of patients afflicted with this ultimately fatal disease.
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PMID:Effective treatment of experimental glioblastoma by HSV vector-mediated TNF alpha and HSV-tk gene transfer in combination with radiosurgery and ganciclovir administration. 1094 38

Our laboratory has employed replication-defective herpes simplex virus type 1 gene transfer vectors for treatment of animal models of human malignant glioblastoma. The base vectors were defective for the immediate early (IE) genes ICP4, ICP27, and ICP22 but expressed the IE gene ICP0, which can arrest tumor cell division, and an IE thymidine kinase (alpha-tk) gene construct that mediates suicide gene therapy (SGT) in the presence of ganciclovir (GCV). Previously, we reported that SGT using ICP0/alpha-tk vectors in nude mouse models of glioblastoma was improved by coexpression of the gap-junction-forming protein connexin43 (Cx43) or human tumor necrosis factor alpha (TNF alpha). We also showed that further gains in therapeutic outcome could be achieved by combining TNF alpha-enhanced SGT with gamma-knife radiosurgery (GKR). To expand these observations, we have first repeated these studies in immunocompetent rats with brain tumors derived from implanted 9L gliosarcoma cells and second compared the most efficient vector from this study with a new recombinant vector, NUREL-C2, which expressed both TNF alpha and Cx43 along with ICP0 and alpha-tk. Results from the first part indicated that our ICP0/alpha-tk/TNF alpha vector in combination with GKR provides an effective therapy although this treatment was not statistically better than GKR combined with the ICP0/alpha-tk/Cx43 vector. Our observations in the second part suggested that NUREL-C2 may be more effective than the ICP0/alpha-tk/TNF alpha vector in combination treatments with GCV (P = 0.08) or GCV plus GKR (P = 0.10). GKR significantly enhanced the efficacy of NUREL-C2/GCV treatment (P = 0.02) as well as other virus/GCV treatments (P < or = 0.05). Conversely, the efficacy of GKR was significantly improved by both the ICP0/alpha-tk/TNF alpha vector and NUREL-C2 in combination with GCV (P = 0.02 and P < 0.01, respectively). Together these results indicate that NUREL-C2 may be an attractive candidate for Phase I gene-therapy safety studies in patients with recurrent malignant glioblastoma.
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PMID:Treatment of rat gliosarcoma brain tumors by HSV-based multigene therapy combined with radiosurgery. 1452 25

Glioblastoma is the most malignant form of primary brain tumor in adults, with no effective therapy and a low survival rate. TRAIL is a member of the TNF family, which selectively induces apoptosis in certain neoplastic cells, but not normal cells. In this study, we investigated the sensitivity of 7 human glioblastoma cell lines to TRAIL and the expression in them of TRAIL receptors. TRAIL exhibited significant cytotoxicity in 5 of 7 glioma cell lines. These glioblastoma cell lines expressed TRAIL-R2, but not TRAIL-R1, R3, or R4. However, no correlation was observed between the TRAIL sensitivity and the TRAIL-R2 expression level, suggesting that there is an additional determinant of TRAIL sensitivity. Treatments with NF-kappaB inhibitors, such as LLnL, MG132, and SN50, significantly increased the sensitivity of glioma cells to TRAIL. These results suggested that activation of NF-kappaB is a protective mechanism against TRAIL-induced cell death in some glioma cells, and thus NF-kappaB inhibitors may be useful to improve the clinical treatment of glioblastoma with TRAIL.
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PMID:Sensitization of human glioblastomas to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) by NF-kappaB inhibitors. 1550 53


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