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

An attractive approach to the therapy of solid tumors would be to target cytotoxic agents or coagulants to the vasculature of the tumor rather than to the tumor cells themselves. This strategy has 3 advantages: (a) it should be applicable to many types of solid tumors because all require a blood supply for survival and growth; (b) the target endothelial cells are directly accessible through the blood and are normal cells, making the outgrowth of resistant mutants unlikely; and (c) there is an in-built amplification mechanism because thousands of tumor cells are reliant on each capillary for nutrients and oxygen. Despite its theoretical attractions, the approach of tumor vascular targeting has not been testable because antibodies that recognize tumor vascular endothelial cell antigens with adequate specificity are currently not available. In this study, we developed a model system in which to investigate the antibody-directed targeting of vascular endothelial cells in solid tumors in mice. A neuroblastoma transfected with the mouse interferon-gamma gene, C1300(Mu gamma), was grown in antibiotic-treated BALB/c nude mice. The interferon-gamma secreted by the tumor induces the expression of major histocompatibility complex Class II antigens on the tumor vascular endothelium. Class II antigens are absent from the vasculature of normal tissues, although they are present on B-lymphocytes, cells of monocyte/macrophage lineage, and some epithelial cells. Anti-Class II antibody administered i.v. strongly stains the tumor vasculature, whereas an antitumor antibody directed against a major histocompatibility complex Class I antigen of the tumor allograft produces classical perivascular tumor cell staining. This model should enable the theoretical superiority of tumor vascular targeting over conventional tumor cell targeting to be tested.
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PMID:A murine model for antibody-directed targeting of vascular endothelial cells in solid tumors. 139 21

We have investigated the effect of interferon-gamma (IFN-gamma) treatment of neuroblastoma cells on the susceptibility to lysis by lymphokine-activated killer (LAK) cells and examined the participation of cell-adhesion molecules on the target cells in LAK cell lysis. Untreated neuroblastoma cells expressed lymphocyte-function-associated antigen 3 (LFA-3) and neural-cell-adhesion molecule (NCAM), but did not express MHC-class-I, MHC-class-II, or intercellular-adhesion molecule I (ICAM-I). IFN-gamma treatment of neuroblastoma cells induced the expression of MHC-class-I and ICAM-I antigens, but did not affect the expression of MHC-class-II, LFA-3, and NCAM. This was accompanied by an increased susceptibility to lysis by LAK cells. Anti-ICAM-I antibody inhibited partially the increased sensitivity of IFN-gamma-treated neuroblastoma cells to LAK cell lysis, and blocked completely the increase in binding of LAK cells observed after IFN-gamma treatment of the target cells. These results suggest that the increased LAK sensitivity of IFN-gamma-treated neuroblastoma cells is partially attributable to the induction of ICAM-I on neuroblastoma cells and indicate that post-binding events also play a role in the increased sensitivity to LAK cell lysis observed after IFN-gamma treatment.
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PMID:Increased susceptibility of IFN-gamma-treated neuroblastoma cells to lysis by lymphokine-activated killer cells: participation of ICAM-1 induction on target cells. 167 70

Differentiation-promoting effects of interferon-gamma (IFN-gamma), both alone and in combination with retinoic acid (RA), were studied on the human neuroblastoma cell line, LA-N-5. The results show that IFN-gamma inhibited the growth and induced morphological differentiation in a dose- and time-dependent manner with measurable effects appearing at 20-40 IU/ml after 3 to 4 days of treatment in vitro. Acetylcholinesterase activity, used as a biochemical index of neuroblastoma differentiation, increased up to 2.5-fold in the presence of IFN-gamma with a half maximal concentration of approximately 100 IU/ml. Concomitantly, modest IFN-induced increases (less than or equal to 2-fold) in choline acetyltransferase (ChAT) and tyrosine hydroxylase (TH) activities were seen. Combination treatment of cells with IFN-gamma and RA resulted in synergistic effects on morphological differentiation, growth inhibition and induction of ChAT. Reversal of IFN-gamma's ability to influence neuroblastoma cell growth as well as potentiate the anti-tumor effects of RA was obtained in the presence of an antibody against the IFN-gamma receptor, implying receptor-mediated physiological events. Taken together, these data confirm the differentiating effects of IFN-gamma on human neuroblastoma cells and suggest that combination therapy with RA may be beneficial in the treatment of this disease.
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PMID:Effects of interferon-gamma and its interaction with retinoic acid on human neuroblastoma differentiation. 167 49

The HT4 cell line was derived from infection of a mouse neuroblastoma cell line with a retrovirus that encoded the temperature-sensitive (ts) mutant of SV40 large T antigen. At nonpermissive temperature, HT4 cells differentiated with neuronal morphology, expressed neuronal antigens, synthesized nerve growth factor (NGF) mRNA, and secreted biologically active NGF in vitro. We sought to establish whether transplanted HT4 cells expressed class I major histocompatibility complex (MHC) antigens, a partial requirement for recognition by cytotoxic T lymphocytes (CTL), and thus be susceptible to xenograft rejection. Differentiated HT4 cells expressed marginally detectable levels of class I MHC antigens, but demonstrated higher levels of class I MHC expression after treatment with interferon-gamma. However, HT4 cells were resistant to direct lysis by perforin, the pore-forming protein of CTLs, and thus may have potential use in xenograft experiments. To address whether HT4 cells secrete NGF in vivo, HT4 cells were transplanted into adults rats with unilateral fimbria-fornix transections. A ts cell line derived from P4 cerebellum, BT1, that does not differentiate with neuronal phenotype or synthesize NGF in vitro, was transplanted as a control. Six weeks posttransplant. HT4 cells had integrated into host CNS without forming tumors. In BT1 transplants, the number of medial septal acetylcholinesterase (AChE)-positive cells was reduced to 26-39% of the contralateral control side, depending on the rostrocaudal level. In HT4 transplants, the number of cholinergic septal neurons was 58-78% of the contralateral side. This percentage was significantly (P less than 0.005) greater than that seen with BT1 transplants, indicating that transplanted HT4 cells secrete NGF in vivo and rescue cholinergic septal neurons following fimbria-fornix transection.
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PMID:Transplantation of a temperature-sensitive, nerve growth factor-secreting, neuroblastoma cell line into adult rats with fimbria-fornix lesions rescues cholinergic septal neurons. 203 46

Activation of peripheral blood lymphocytes from a neuroblastoma patient by co-cultivation with autologous neuroblastoma cells in a mixed lymphocyte-tumor cell culture (A-MLTC) resulted in the generation of cytotoxic activity against the autologous neuroblastoma cell line HNB-MS. A-MLTC was set up in the presence of recombinant human interleukin-2 (IL-2). HNB-MS stimulator was treated with recombinant human interferon-gamma (IFN-gamma) prior to A-MLTC. CTL generated in short-term culture effectively lysed HNB-MS, while they had no effect on an Epstein-Barr virus transformed autologous B-cell line EB-MS. Moreover, CTL lysed 3 different allogeneic neuroblastoma cell lines, but not a rhabdomyosarcoma cell line RBB. Recombinant human tumor necrosis factor-alpha (TNF-alpha) and interleukin-4 (IL-4) enhanced and suppressed CTL generation, respectively, when added to the A-MLTC from the beginning of culture. CD3+ CD4- CD8+ T cells were the major anti-tumor effectors. Furthermore, 111indium-labeled CTL clearly accumulated in metastatic sites. These results indicate that CTL can be used for adoptive immunotherapy in neuroblastoma.
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PMID:Autologous tumor-specific cytotoxic T-lymphocytes in a child with neuroblastoma. 208 62

The in vitro and in vivo influence of interleukin-2 (IL-2) on 2',5'-oligoadenylate (2-5A) synthetase activity and natural killer (NK) activity of peripheral mononuclear blood cells (PBMCs) was investigated. Incubation of PBMCs in vitro with IL-2 resulted in a considerable secretion of interferon-gamma (IFN-gamma) and in a significant elevation of 2-5A synthetase activity, as well as NK activity. Neutralizing monoclonal anti-IFN-gamma antibodies inhibited the elevation of 2-5A synthetase activity, but not the IL-2-induced augmentation of NK activity. Additionally, 2-5A synthetase and NK activity of PBMCs was measured in a child with neuroblastoma that was treated with recombinant IL-2 by continuous intravenous application. During the treatment, NK activity against the NK-sensitive cell line K 562 and against autologous tumor cells was not augmented. However, a significant increase of 2-5A synthetase activity in PBMCs was observed during IL-2 treatment, whereas there was no detectable serum level of IFN-gamma. We conclude that measuring 2-5A synthetase activity in patients treated with IL-2 may be helpful in monitoring the immunomodulatory effects of IL-2 on immune effector cells.
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PMID:In vitro and in vivo effect of interleukin-2 on the 2',5'-oligoadenylate synthetase activity of peripheral mononuclear blood cells. 210 81

Cells of two human neuroblastoma lines, GOTO and KP-N-RT-LN, differentiated in response to treatment with 1,000 IU/ml of recombinant human interferon-gamma (rIFN-gamma), but did not respond to rIFN-alpha 2 or IFN-beta. Treatment with rIFN-gamma rapidly increased the phosphorylation of several cell proteins; in particular, there was enhanced phosphorylation of a 61-kD protein within 1 min after treatment. This enhancement was not observed in variant sublines of GOTO cells, which did not differentiate when treated with rIFN-gamma. These findings suggest that when neuroblastoma cells are induced to differentiate by treatment with rIFN-gamma, phosphorylation of the 61-kD protein plays an important role.
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PMID:Rapid phosphorylation of cellular proteins during differentiation of neuroblastoma cells induced by recombinant human interferon-gamma. 212 53

Interferon-gamma-induced tryptophan metabolism of human macrophages was compared to ten human neoplastic cell lines of various tissue origin and to normal dermal human fibroblasts. Tryptophan and metabolites were determined in supernatants of cultures, after incubation for 48 h, by high-performance liquid chromatography with ultraviolet and fluorescence detection. With the exception of two cell lines (Hep G 2, hepatoma and CaCo 2, colon adenocarcinoma) in all of the ten other cells and cell lines tryptophan degradation was induced by interferon-gamma. Five of these ten formed only kynurenine (SK-N-SH, neuroblastoma; T 24, J 82, bladder carcinoma; A 431, epidermoid carcinoma; normal dermal fibroblasts), three formed kynurenine and anthranilic acid (U 138 MG, glioblastoma; SK-HEP-1, hepatoma; A 549, lung carcinoma). Only one line, A 498 (kidney carcinoma) showed the same pattern of metabolites as macrophages (kynurenine, anthranilic acid and 3-hydroxyanthranilic acid). Interferon-gamma regulated only the activity of indoleamine 2,3-dioxygenase. All other enzyme activities detected were independent of interferon-gamma, as shown by the capacity of the cells to metabolize L-kynurenine or N-formyl-L-kynurenine. Increasing the extracellular L-tryptophan concentration resulted in a marked induction of tryptophan degradation by macrophages. Contrarily, a significant decrease of the tryptophan degrading activity was observed when the extracellular L-tryptophan concentration was increased 2-fold with SK-N-SH, T 24 and J 82, 4-fold with A 431 and A 549 and 10-fold with U 138 MG and SK-HEP-1. The activity was unaffected by extracellular L-tryptophan with dermal fibroblasts and A 498. Though interferon-gamma was the most potent inducer of tryptophan metabolism, interferon-alpha and/or -beta showed small but distinct action on some of the cells. In all cells which reacted to interferon-gamma by enhanced expression of class I and/or class II major histocompatibility complex antigens tryptophan degradation was also inducible. These results demonstrate that induction of indoleamine 2,3-dioxygenase is a common feature of interferon-gamma action, that the extent of this induction is influenced by extracellular L-tryptophan concentrations and that indoleamine 2,3-dioxygenase is the only enzyme in the formation of 3-hydroxyanthranilic acid from tryptophan which is regulated by interferon-gamma.
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PMID:Characteristics of interferon induced tryptophan metabolism in human cells in vitro. 250 Sep 76

The influence of interferon-gamma on the susceptibility of neuroblastoma cells in cell-mediated killing was investigated. Neuroblastoma cells were only weakly susceptible targets for peripheral mononuclear cells. However, enrichment of natural killer (NK) cells or activation of NK cells with interleukin-2 resulted in a considerable increase of neuroblastoma cell lysis. Pretreatment of neuroblastoma targets with interferon-gamma additionally increased the susceptibility to enriched NK cells as well as to interleukin-2-activated NK cells. The conjugate formation between enriched NK cells and the neuroblastoma targets was not affected by the pretreatment of the targets with interferon-gamma. Concomitantly, treatment of the neuroblastoma targets with interferon-gamma resulted in a strong induction of otherwise poorly expressed major histocompatibility complex (MHC) class I antigen expression. These results suggest that the increased expression of MHC class I antigens on target cells is not always correlated with decreased sensitivity for NK cells but can also be followed by an increased susceptibility for NK cells.
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PMID:Interferon-gamma upregulates the susceptibility of human neuroblastoma cells to interleukin-2-activated natural killer cells. 250 5

To investigate the effect of interferon-gamma (IFN-gamma) on the immunotherapy, we used the autocrinically stimulated system in which a mouse IFN-gamma cDNA was transferred by infection with a chimeric retrovirus containing the IFN-gamma gene. First, we established a tumor specific CTL clone (E-4) against 203-glioma cells (a 20-methylcholanthrene induced mouse ependymoblastoma line of C57BL/6 mouse origin), and then transferred murine IFN-gamma cDNA into E-4 by using retroviral vector (pSVX(Mu gamma delta A]. Out of five gene-transferred subclones, E gamma-4, E gamma-5, E gamma-6, E gamma-7 and E gamma-9, two subclones (E gamma-6 and E gamma-9) constitutively produced 8- to 10-fold amounts of IFN-gamma as compared with the parental E-4. Moreover, these two subclones exhibited two to three times higher killing activity against 203-glioma than the parental cells. The enhancement of the killing activities was abrogated by an adequate addition of anti-IFN-gamma antibody. No alteration was seen after the gene transfer in cell surface phenotypes, Thy-1+, Lyt-1-, Lyt-2+3+ and asialo-GM1-. Fluorescence-activated cell sorter (FACS) analysis showed that the surface expression of major histocompatibility complex (MHC) Class I antigen, H-2Kb, of parental E-4 was augmented remarkably, and it was not altered by the IFN-gamma gene transfer, but the Class II antigen, I-Ab, was slightly enhanced on the two IFN-gamma-producing sublines. Since it is considered that in the vicinity of the constitutively IFN-gamma-producing CTL cells, tumor cells are exposed to a high concentration of IFN-gamma and may be stimulated to induce or enhance the expression of surface antigens including MHC antigens as well as tumor associated antigens in relation to immune recognition. The 203-glioma cells pretreated with IFN-gamma were more efficiently killed by both the parental E-4 and the gene-transferred sublines. It was thus suggested that the specific tumor killing activity of the gene-transferred CTLs was augmented by the constitutive production of IFN-gamma derived from the exogenous gene. As the next step, a mouse IFN-gamma cDNA was transferred into a neuroblastoma line C1300 of A/JAx mouse origin. Two infected subclones C gamma 3 and C gamma 22, were obtained as a low and a high producers, respectively. Both IFN-gamma gene transferred cells remained unchanged as regards in vitro cell growth, morphological appearance and differentiation antigen expression such as neurofilaments after the IFN-gamma gene transfer. On the other hand, expression of MHC Class I antigens of both subcloned lines was extremely augmented at the surface expression level as well as at the transcription level, re
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PMID:[A novel experimental approach to immunotherapy against malignant brain tumor with the mouse IFN-gamma gene transfer]. 250 89


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