Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027819 (neuroblastoma)
 27,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Both IFN-alpha/beta and IFN-gamma have recently been demonstrated to induce a rapid but transient activation of phospholipase A2 (PLA2) in BALB/c 3T3 fibroblasts and a human neuroblastoma cell line. We report that IFN-gamma induces the synthesis and prolonged activation of cytosolic phospholipase A2 (cPLA2) in a human bronchial epithelial cell line (BEAS 2B). Treatment of the cells with IFN-gamma (300 U/ml) increased the release of [3H]arachidonic acid (AA) from prelabeled cells with a maximal effect at 12 h after stimulation. The increased [3H]AA release was inhibited by the PLA2 inhibitor p-bromophenacyl bromide (10(-5) M). Calcium ionophore A23187 (10(-5) M) further increased the [3H]AA release from the IFN-gamma-treated cells. Subcellular enzyme activity assay revealed that IFN-gamma increased PLA2 activity in both the cytosol and membrane fractions with a translocation of the cPLA2 to cell membranes in a Ca(2+)-free cell lysing buffer. Treatment with IFN-gamma also induced the release of 15-HETE, an arachidonic acid metabolite. Immunoblot showed that IFN-gamma induced the synthesis of cPLA2 protein. Nuclear run-on assay demonstrated that IFN-gamma initiated cPLA2 gene transcription within 15 min, and this effect was sustained at 4 h and returned to near control level at 12 h. The cPLA2 mRNA level was assayed by reverse transcription and PCR. IFN-gamma was found to increase the cPLA2 mRNA after 2-24 h treatment. Furthermore, the IFN-gamma induced cPLA2 mRNA increase was blocked by inhibitors of protein kinase C and calcium/calmodulin-dependent protein kinases, suggesting the involvement of these protein kinases in IFN-gamma-induced gene expression of cPLA2. This study shows that IFN-gamma induces the synthesis and prolonged activation of cPLA2.
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PMID:Interferon-gamma induces the synthesis and activation of cytosolic phospholipase A2. 811 94

Three human neuroblastoma cell lines were examined to determine the effect of recombinant gamma-interferon (IFN-gamma) treatment on the expression of trk proto-oncogene. Increased levels of trk proto-oncogene mRNA were observed in two neuroblastoma cell lines (KP-N-RT and KP-N-SI(FA)) after IFN-gamma treatment. The levels of trk mRNA increased with growth inhibition and morphological change in a time- and dose-dependent manner. The decreased level of N-myc mRNA after IFN-gamma treatment in KP-N-RT was inversely correlated with trk mRNA. Our results suggest that IFN-gamma can modulate the signal transduction of nerve growth factor in human neuroblastoma cells.
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PMID:Increased expression of trk proto-oncogene by gamma-interferon in human neuroblastoma cell lines. 814 93

Recombinant gamma-interferon (IFN-gamma) has recently been shown to be one of the most effective inducers of neuroblastoma (NB) cell differentiation. Since increasing evidence indicates that expression of MHC class-I and class-II antigens by tumour cells is important for immunorecognition and cell targeting, we tested whether induction of NB cell differentiation by IFN-gamma is followed by expression of HLA class-I and class-II molecules. LAN-5 human NB cell line completely lacks HLA class-I antigens. Their expression was induced in a dose-dependent manner by IFN-gamma. HLA class-II molecules are also absent on LAN-5 cells, but only DP antigens were dose-dependently induced by IFN-gamma, while DR and DQ molecules were unaffected by the treatment. To confirm and extend the immunological data to all the class-II molecules, we performed Northern blot analysis, observing that DP alpha mRNA was induced in a dose- and time-dependent manner. DO beta and DZ alpha genes were also induced peaking after 3 days of IFN-gamma treatment. DR beta and DQ beta genes, which were not induced by IFN-gamma, gave a normal pattern of enzyme restriction by Southern blot. To get an insight into the regulation of HLA class-II gene expression in the neuronal model, we measured the decline of the steady-state HLA class-II mRNA. DO beta mRNA rapidly returned to baseline level after removing IFN-gamma, while the decay rates of DP alpha and DZ alpha mRNA were very slow. This might indicate different regulation at the post-transcriptional level for DO beta mRNA with respect to DP alpha and DZ alpha mRNA. To strengthen these findings we evaluated the half-lives of the mRNA after IFN-gamma induction by means of actinomycin D treatment. HLA-DO beta mRNA had a shorter half-life, while DZ alpha and DP alpha had a longer decay rate. Finally, we report that treatment of LAN-5 cells with cycloheximide did not alter the rate of transcription of the HLA-DP alpha gene, suggesting that no protein factor(s) is/are needed to maintain DP alpha gene expression.
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PMID:Uncoordinate induction and differential regulation of HLA class-I and class-II expression by gamma-interferon in differentiating human neuroblastoma cells. 824 79

MHC class I molecules are coexpressed with beta 2-microglobulin (beta 2-M) on many somatic cells. However, these proteins are normally not present on cells of the central nervous system (CNS). Cells derived from human neuroblastomas were used as a model for investigating the molecular basis for the paucity of MHC class I and beta 2-M gene expression in neural cells and for the induction of these genes by two cytokines, IFN-gamma, and TNF-alpha. These cytokines independently increased MHC class I and beta 2-M cell surface expression on the neuroblastoma cell lines. IFN-gamma or TNF-alpha also increased MHC class I and beta 2-M steady-state RNA levels and the expression of MHC class I and beta 2-M CAT reporter constructs transiently transfected into the neuroblastoma cell lines, indicating that the cytokines acted by increasing the transcription of these genes. MHC class I and beta 2-M genes share two conserved regulatory elements, an NF kappa B-like site and the IFN consensus sequence, that act as a constitutive enhancer and an IFN-responsive element, respectively. Low MHC class I and beta 2-M gene expression in these cells was accounted for by undetectable to low factor binding activity specific for the above regulatory elements of these genes. TNF-alpha increased factor binding activity specific for the NF kappa B-like elements and IFN-gamma increased factor binding activity specific for the IFN consensus sequence elements of the MHC class I and beta 2-M genes, but not vice versa. Taken together, our results indicated that IFN-gamma and TNF-alpha increased MHC class I and beta 2-M gene expression in the neuroblastoma cell lines by inducing factor binding to the regulatory elements present in both genes.
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PMID:Regulation of MHC class I and beta 2-microglobulin gene expression in human neuronal cells. Factor binding to conserved cis-acting regulatory sequences correlates with expression of the genes. 846 72

Murine neuroblastoma, neuro-2a, was transduced with the retroviral vector MFG-granulocyte-macrophage colony-stimulating factor (GM-CSF), to examine immune stimulation conferred by localized GM-CSF production. Expression of murine GM-CSF by neuro-2a (N-2a/GM) significantly reduced its tumorigenicity. Moreover, immunization of mice with irradiated N-2a/GM cells resulted in a significant protective effect against live tumor challenge 14 days later. Approximately 41% of mice immunized with irradiated N-2a/GM versus 0% of those vaccinated with irradiated parental tumor survived. Surviving mice were rechallenged after 50 days with wild-type neuro-2a or with the Sa1 syngeneic sarcoma to discern whether the generated immunity was durable and tumor specific. All mice survived wild-type neuro-2a challenge, whereas none survived inoculation with Sa1. Because both CD4+ and CD8+ T cells were necessary during priming to this MHC class Ilo, II-tumor, these data indicate that major histocompatibility complex (MHC) class I+, II+ antigen-presenting cells (APCs) were required for the T-cell antitumor response. Co-expression of GM-CSF and IFN-gamma, both of which have immunostimulatory activities on antigen-presenting cells, abrogated the tumorigenic potential of this tumor and increased immunogenicity over N-2a/IFN but not N-2a/GM. Vaccination of mice with preexisting retroperitoneal tumors with irradiated N-2a/GM and irradiated N-2a/IFN/GM improved survival. There was a trend for nonirradiated transduced cells to be more immunogenic than their irradiated counterparts. Immunohistochemistry of tissues from the vaccination site revealed a pronounced macrophage infiltration associated with nonirradiated N-2a/GM and N-2a/IFN/GM. These data suggest that vaccination involving nonirradiated neuroblastoma cells transduced with genes that stimulate APCs may be a useful approach in stimulating antitumor T-cell responses.
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PMID:Effective immunization against neuroblastoma using double-transduced tumor cells secreting GM-CSF and interferon-gamma. 873 94

Prion diseases are a group of neurodegenerative disorders characterized by intracerebral accumulation of a protease-resistant prion protein (PrP(Sc)) that causes extensive neuronal degeneration and astrogliosis. The regulation of prion protein (PrP) gene expression by a panel of glial and neuronal cytokines (TNF-alpha, IFN-gamma, IL-1beta, IL-10, and TGF-beta1) was investigated in human neural cell lines by reverse transcription-polymerase chain reaction and Northern blot analysis. The constitutive expression of PrP mRNA was identified in all human neural cell lines and tissues examined including Y79 retinoblastoma, IMR-32 neuroblastoma, SK-N-SH neuroblastoma, U-373MG astrocytoma, KG-1-C glioma, NTera2 teratocarcinoma, NTera2-derived differentiated neurons (NTera2-N), peripheral nerve, and cerebral and cerebellar tissues. In SK-N-SH cells, a 48 hour (h) treatment with 100 ng/ml IL-1beta, 100 ng/ml TNF-alpha, or 100 nM phorbol 12-myristate 13-acetate induced a 2.7- to 4.2-fold increase in the level of PrP mRNA, while the exposure to 100 ng/ml IFN-gamma resulted in a 50% decrease. By contrast, none of these cytokines significantly altered the levels of PrP mRNA in IMR-32, NTera2-N, or U-373MG cells. These results indicate that the PrP gene expression is constitutive in a wide range of human neural cell lines and tissues where it is controlled by cell type-specific regulatory mechanisms.
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PMID:Constitutive and cytokine-inducible expression of prion protein gene in human neural cell lines. 960 Feb 5

Interleukin 12 (IL-12) is a pleiotropic cytokine and mediates several biological activities on human T and natural killer (NK) cells, including induction of IFN-gamma production, enhancement of cell-mediated cytotoxicity and comitogenic effects on resting T-cells. The major cellular sources producing IL-12 are antigen-stimulated monocytes, macrophages, and B-cells isolated from peripheral blood mononuclear cells (PBMC). Our laboratory has investigated the regulation of IL-12 gene expression in both cord blood and adult PBMC, and the effects of IL-12 on induction of IFN-gamma production, NK, and lymphokine-activated killer (LAK) cytotoxicity. IL-12 mRNA expression and protein production in LPS-stimulated cord blood MNC were 3-4 fold decreased when compared with adult PBMC. There were no differences between cord blood and adult PBMC in both basal levels of transcription or the degree of transcriptional activation of the IL-12 gene. Additionally, the half-life of IL-12 p40 mRNA was 3-fold lower in activated cord blood compared to adult PBMC. Exogenous IL-12 induced a significant increase of IFN-gamma from both cord and adult PBMC. Cord MNC has significantly reduced levels of NK activity, and IL-12 significantly enhanced cord blood NK cytotoxicity up to similar levels in adult PBMC. IL-12 also significantly enhanced cord blood NK and LAK activities against a broad range of neuroblastoma, leukemia, and lymphoma cell lines. Lower doses of IL-12 and IL-15 concomitantly generated either synergistic or additive effects on cord blood NK and LAK cytotoxicities. In light of the important biological functions of IL-12, reduced expression and production of IL-12 from activated cord blood may contribute to the immaturity of cord blood cellular immunity and contribute, in part, to decreased severe graft vs. host disease following unrelated cord blood stem cell transplantation. IL-12 enhancement of IFN-gamma, NK, and LAK activity in activated cord blood MNC up to comparable levels in adult PBMC suggests that exogenous IL-12 stimulation can compensate for the immaturity in cord blood cellular immunity. These characteristics of IL-12 biological activity strongly suggest its potential usefulness in future cancer immunotherapy.
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PMID:The regulation and biological activity of interleukin 12. 964 57

Although not structurally related, the pleiotropic cytokines interleukin-7 (IL-7) and interleukin-15 (IL-15) share a variety of biological functions including stimulation and maintenance of cellular immune responses. Cytokines, such as IL-7 or IL-15, elaborated by cells in situ, e.g. cancer cells, may be involved in shaping the quality of anti-tumor directed immune responses. We have analysed the constitutive and IFN-gamma-inducible expression of IL-15 or IL-7 mRNA, protein expression, and protein secretion in human tumor cell lines of distinct origin. IL-15 mRNA expression was detected in renal cell carcinoma (RCC), small cell lung carcinoma (SCLC), glioblastoma, neuroblastoma, mesothelioma cells and in EBV-transformed B-lymphocytes. IL-7-specific transcripts could be detected in colorectal cancer and in renal cell cancer cell lines. Immunohistochemical analysis demonstrated cytosolic IL-15 protein expression in renal cell cancer cells without apparent IL-15 protein secretion in vitro. Time kinetic analyses revealed that IFN-gamma mediated increase of IL-15 mRNA expression was transcriptionally regulated and dependent on de novo protein synthesis. However, enhanced IL-15 mRNA expression did not lead to effective protein secretion. In contrast, IL-7 mRNA expression in renal cell cancer or in colorectal cancer was associated with effective protein secretion which could be augmented by IFNgamma-treatment. These data suggest that both IL-7 and IL-15 mRNA are expressed in renal cell cancer, but exclusively IL-7 may be elaborated by tumor cells in situ. IL-15 regulation appears to be tightly controlled both at the transciptional and post-transcriptional level. Appropriate stimuli leading to effective IL-15 secretion from tumor cells may aid in modulating cellular immune responses directed against cancer.
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PMID:Constitutive and IFN-gamma regulated expression of IL-7 and IL-15 in human renal cell cancer. 986 5

Retroviral constructs were designed to express the novel cytokine interleukin 18 (IL-18), also known as interferon-gamma-inducing factor, in a murine neuroblastoma cell line [neuro-2a (N-2a)] to examine the effects of IL-18 expression on tumorigenicity. N-2a cells expressing proIL-18 (N-2a/IL-18p) were as tumorigenic as parental N-2a cells, whereas N-2a cells engineered to secrete mature IL-18 (N-2a/IL-18m) were nontumorigenic. Inoculation of mice with N-2a/IL-18m generated immediate immunity to parental N-2a. N-2a/IL-18m formed tumors in mice depleted of CD4+ and CD8+ T cells, suggesting that the antitumor immune response was T cell mediated. The resulting T-helper (Th) immune response was also characterized in vitro and had a large Th1 component based on in vitro production of the cytokines IFN-gamma and granulocyte macrophage colony-stimulating factor in response to tumor cells and IL-18.
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PMID:Neuroblastoma cells expressing mature IL-18, but not proIL-18, induce a strong and immediate antitumor immune response. 1040 34

Complement activation products C1q, C4c/d, and C3c/d in amyloid plaques in Alzheimer's disease probably result from direct binding and activation of C1 by amyloid beta peptides. RT-PCR and in situ hybridization studies have shown that several complement factors are produced in the brain parenchyma. In the present study, cytokines that can be detected in amyloid plaques (i.e., interleukin (IL)-1, IL-6, and tumor necrosis factor (TNF)-alpha) were found to differentially stimulate the expression of C1 subcomponents, C1-Inhibitor (C1-Inh), C4, and C3, by astrocyte and microglial cell cultures derived from postmortem adult, human brain specimens and by neuroblastoma cell lines in culture. C1r and C1s were secreted at low levels by astrocytes and neuroblastoma cell lines. Exposure of cells to IL-1 alpha, IL-1 beta, TNF-alpha and to a far lesser extent IL-6, markedly upregulated C1r, C1s, and C3 production. C4 synthesis increased in response to interferon (IFN)-gamma and IL-6, whereas that of C1-Inh could be stimulated only by IFN-gamma. Thus, C1-Inh production is refractory to stimulation by plaque-associated cytokines, whereas these cytokines do stimulate C1r, C1s, and also C4 and C3 secretion by astrocytes and neuronal cells in culture. In contrast to the amyloid plaque associated cytokines IL-1 beta, IL-1 alpha, and TNF-alpha, the amyloid peptide A beta 1-42 itself did not stimulate C1r and C1s synthesis by astrocytes, microglial cells, or neuroblastoma cell lines. Microglial cells were the only cell type that constitutively expressed C1q. The ability of C1q to reassociate with newly formed C1r and C1s upon activation of C1 and subsequent inactivation by C1-Inh, may enable ongoing complement activation at sites of amyloid deposition, especially when C1-Inh is consumed and not replaced.
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PMID:Cytokines associated with amyloid plaques in Alzheimer's disease brain stimulate human glial and neuronal cell cultures to secrete early complement proteins, but not C1-inhibitor. 1063 Feb 13


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