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)

Regulation of beta 1 integrins in neurite outgrowth following N6,2'-O-dibutyryladenosine 3':5'-cyclic monophosphate (dBcAMP) treatment was investigated using the human neuroblastoma cell line TR 14. Three beta 1 integrins were identified: the alpha 1 beta 1 receptor bound collagen type I, collagen type IV and probably laminin; the alpha 2 beta 1 integrin bound collagen type I; and the alpha v beta i receptor bound fibronectin. Neurite extension was detectable as early as 30 minutes following dBcAMP treatment, was maximal after 24 hours and remained constant during treatment for 4 days. Adhesion-perturbing beta 1 subunit-specific antibodies, added together with dBcAMP, prevented the outgrowth of new neurites. During the first 24 hours of neurite outgrowth, no change was observed in the amount of beta 1 integrins nor in their topographic distribution. However, dBcAMP treatment increased the binding of alpha 1 beta 1 receptors to collagen type IV-Sepharose by a factor 2.3 +/- 0.6 (P < 0.02), while no alteration in the binding to collagen type I was detected. Moreover, neurites and growth cones were immunoreactive for collagen type IV but not for collagen type I. Consistently dBcAMP-induced neurite outgrowth was inhibited by adhesion-perturbing alpha 1 subunit-specific antibodies. Following maximal neurite outgrowth, the amount of beta 1 integrins determined by immunoprecipitation and by confocal microscopy decreased to 58.3 +/- 11.2% (P < 0.001) and to 55.4 +/- 17.5% (P < 0.001) of untreated levels, respectively, without any change in the level of beta 1 mRNA or de novo synthesized beta 1 precursor. However, pulse-chase experiments showed an increased turnover of the beta 1 subunit: the amount of beta 1 precursor that was degraded after 1 hour chase was 50.5 +/- 8.4% in cells treated for 4 days and 34.2 +/- 3.9% in untreated cells (P < 0.02); the amount of mature beta 1 after 24 hours chase was smaller in cells treated for 4 days compared to untreated cells. In conclusion, during neurite outgrowth, alpha 1 beta 1 integrins are required and acquire an enhanced binding activity for collagen type IV; but following maximal neurite outgrowth, expression of beta 1 integrins is reduced.
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PMID:Selective increase in the binding of the alpha 1 beta 1 integrin for collagen type IV during neurite outgrowth of human neuroblastoma TR 14 cells. 753 84

The immunohistological expression of integrins and CD44 cell adhesion molecule was analyzed on neuroblastoma (NB) specimens to study the potential role of these molecules in normal differentiation and in the transformation of neural crest derivatives. None of the specimens expressed the alpha 5 beta 1 integrin heterodimer; the expression of alpha 3 beta 1 heterodimer was maintained during all stages of differentiation; alpha 1 beta 1 heterodimer was expressed on undifferentiated neuroblasts and on Schwann cells, but was lost on ganglion cells. In contrast alpha 2 beta 1, alpha 6 beta 1, alpha 6 beta 4 and alpha V beta 1 expression was usually restricted to cells differentiated in the Schwann cell lineage. Alpha V beta 3 was expressed on tumors developed in the mediastinum. CD44 was strongly detected on differentiated ganglioneuroblastomas, stage 1 and 2 ganglioneuromas, as well as low-grade stage 4S NB and normal neuroblasts migrating in the fetal adrenal gland. CD44 expression was observed on Schwann cells and ganglion cells; in contrast, it was expressed on only 50% stage 3 and 4 undifferentiated NB. None of these specimens expressed exons V5, V7 or V6. In a few specimens, an intracellular expression of exons V8-V10 was observed in ganglion cells. The expression of CD44 on NB may reflect its pattern of expression on sympatho-adrenal precursors and arrest differentiation at these stages. Conversely, CD44 expression may be silenced during malignant transformation.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Expression of integrin and CD44 adhesion molecules on neuroblastoma: the relation to tumor aggressiveness and embryonic neural-crest differentiation. 754 74

The beta 1 integrin subfamily, alternatively called very late activation antigen (VLA), has been implicated in various cellular functions. In this study, we generated a mAb against the mouse beta 1 subunit (CD29) to examine the functional property of mouse VLA proteins. After immunization with affinity-purified mouse VLA-4 (alpha 4 beta 1), a hamster mAb, HM beta 1-1, was established by screening mAb that reacted with alpha 4-negative neuroblastoma C1300. The antigen defined by HM beta 1-1 was widely distributed in various mouse cell lines and HM beta 1-1 immunoprecipitated a 110-120 kDa protein common to VLA-1 and VLA-6, indicating that HM beta 1-1 recognizes the beta 1 subunit of mouse integrins. We then examined the inhibitory effect of HM beta 1-1 on VLA-dependent cell adhesion and activation. HM beta 1-1 blocked the adhesion of mouse tumor cell lines to extracellular matrix proteins including collagen, laminin and fibronectin. Moreover, splenic T cell proliferation induced by anti-CD3 mAb and allogeneic mixed lymphocyte response were strongly inhibited by HM beta 1-1 in combination with an anti-LFA-1 mAb. We conclude that HM beta 1-1 reactive with mouse CD29 can inhibit VLA-dependent cellular functions and, thus, would be useful for studying the physiological role of beta 1 integrins in vivo.
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PMID:Identification and functional characterization of mouse CD29 with a mAb. 754 9

Integrins belong to a large family of heterodimeric membrane glycoproteins which mediate cell-cell or cell-extracellular matrix interactions. These interactions could play a major role during the migration of tumor cells across the extracellular matrix and vascular endothelium and would thus appear to be requisite for the metastatic process. Pretreatment of the Foss human melanoma cell line with HILDA/LIF or OSM, two cytokines involved in acute-phase response, increased the expression of membrane alpha v beta 1 1.5-2-fold. The same phenomenon was observed on the SK-N-SH human neuroblastoma cell line. alpha v beta 1 upmodulation was concomitant with improved tumor cells attachment to the fibronectin matrix. This greater adhesion of tumor cells to fibronectin was inhibited by specific monoclonal antibodies against alpha v or beta 1 integrin subunits. Similar results were obtained after TNF-alpha treatment. Our findings demonstrate the ability of HILDA/LIF and OSM to modulate tumor cell capacity to adhere to the matrix component, suggesting a potential role for these cytokines in modulation of tumoral progression.
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PMID:Upmodulation of alpha v beta 1 integrin expression on human tumor cells by human interleukin for DA cells/leukemia inhibitory factor and oncostatin M: correlation with increased cell adhesion on fibronectin. 759 53

The 39- to 43-amino acid amyloid beta-protein (A beta) is deposited as amyloid in Alzheimer's disease. Recent studies have suggested that short A beta (A beta 39 or A beta 40) and long A beta (A beta 42 or A beta 43) play different roles in Alzheimer-type pathology. However, little attempt has been made to investigate the cellular mechanisms underlying the generation of short and long A beta individually. In the present report, we first measured the amount of short and long A beta that are secreted from wild-type human and rodent cells with neuron- or glia-like properties using highly sensitive sandwich-ELISAs that discriminate long A beta from short A beta. The results showed that long A beta secreted by all cells constitutes approximately 10% of the total A beta. To identify the molecular species of long A beta, we next isolated the A beta species secreted from human neuroblastoma IMR-32 cells by affinity chromatography, gel-filtration HPLC, and reverse-phase HPLC. Mass spectrometric analysis demonstrated unequivocally that IMR-32 cells produce A beta 1-42 together with A beta 1-37, A beta 1-38, A beta 1-39, and most predominantly, A beta 1-40. Finally, to investigate the cellular mechanisms that generate A beta 1-42, we studied the effects of brefeldin A and monensin on the production of A beta 1-40 and A beta 1-42 in IMR-32 cells. These reagents reduced the production of both A beta 1-40 and A beta 1-42 simultaneously in a concentration-dependent manner.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Long amyloid beta-protein secreted from wild-type human neuroblastoma IMR-32 cells. 764 Feb 83

A phase I trial of a murine anti-ganglioside (GD2) monoclonal antibody (mAb) 14G2a was conducted in 14 neuroblastoma patients and 1 osteosarcoma patient to assess its safety, toxicity and pharmacokinetics in pediatric patients. The pharmacokinetics of mAb 14G2a were biphasic with a t alpha 1/2 of 2.8 +/- 2.8 h and a t beta 1/2 of 18.3 +/- 11.8 h. In general, t beta 1/2 was dose-dependent with a level of significance of P = 0.036, and it reached a plateau at doses of 250 mg/m2 or more. Overall the peak serum levels were dose-dependent at P < 0.001. However, they demonstrated an abrupt increase between doses of 100 mg/m2 and 250 mg/m2. The latter two suggest a saturable mechanism for mAb elimination. In addition, peak serum concentrations were observed earlier at higher mAb doses, which indicates the achievement of a steady state. The t beta 1/2 of mAb 14G2a in children appears to be shorter than in adults. Furthermore, 2 patients demonstrated a considerable decrease in t beta 1/2 following retreatment with 14G2a. This was paralleled by high human anti-(mouse Ig) antibody levels. This study represents the first comprehensive analysis of murine mAb pharmacokinetics in children and will be useful in the future design of mAb therapy.
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PMID:Pharmacokinetics of anti-ganglioside GD2 mAb 14G2a in a phase I trial in pediatric cancer patients. 764 Dec 17

The authors investigated the effects of a nontoxic differentiation inducer, phenylacetate (PA), on neuroectodermal tumor-derived cell lines. Treatment of medulloblastoma (Daoy and D283 MED) and glioma (U-251MG, C6, and RG2) cell lines resulted in a dose-dependent decline in DNA synthesis and cell proliferation, associated with accumulation in the G0/G1 phase of the cell cycle. Phenylacetate decreased transforming growth factor (TGF)-beta 2 production by medulloblastoma Daoy cells. Neutralizing antibodies against either TGF beta 2 or TGF beta 1 failed to block the growth arrest observed. This suggests that, unlike other differentiation agents, such as retinoic acid, the effect of PA on medulloblastoma proliferation is not mediated by a TGF beta pathway. In addition to cytostasis, PA induced marked morphological changes in U-251MG and C6 glioma cells associated with increased abundance of glial fibrillary acidic protein-positive processes. Although the morphology of PA-treated medulloblastoma cells was not significantly altered, the D283 MED cells exhibited increased expression of neurofilament proteins and Hu antigen, indicative of differentiation along a neuronal pathway. The effects of PA on the medulloblastoma cell lines were compared to its effects on the human neuroblastoma cell line BE(2)C, which is capable of a bidirectional differentiation toward a neuronal or a glial/schwann cell pathway. In BE(2)C cells, PA induced differentiation toward a schwann/glial cell-like phenotype, suggesting that the choice of differentiation pathway is cell type and agent specific. These in vitro antiproliferative and differentiation inducing effects of PA suggest that this agent warrants further evaluation as a potential therapeutic modality for the treatment of medulloblastoma and malignant glioma in humans.
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PMID:Inhibition of proliferation and induction of differentiation in medulloblastoma- and astrocytoma-derived cell lines with phenylacetate. 767 18

Two human neuroblastoma cell lines, LAN-5 and GI-CA-N, have been analyzed for their capability to adhere to different extracellular matrix (ECM) components. The GI-CA-N cells adhered to all the tested substrates: laminin (LN), type I and type IV collagen (Coll I, Coll IV), vitronectin (VN), and fibronectin (FN). Conversely LAN-5 cells weakly attached to FN and VN, whilst adhesion on LN and Coll I and IV was strong and induced a rapid elongation of cell processes. By means of RT-PCR and immunoprecipitation we showed that the integrin pattern of these two lines was different and could explain their diversity in adhesion capability. Both cell lines express a large amount of the beta 1 integrin subunit, associated with different alpha chains, probably responsible for their adhesion to some ECM proteins. After treatment of LAN-5 cells with biological differentiating agents, such as gamma-interferon, alone or in combination with tumour necrosis factor-alpha (TNF-alpha), or retinoic acid, the levels of alpha 1 beta 1, alpha 2 beta 1, and alpha 3 beta 1 integrin expression were enhanced, while the amount of alpha v remained constant. In contrast, treatment of LAN-5 cells with TNF-alpha, that did not induce any maturation, or starvation in 2% foetal calf serum, that inhibited cell proliferation without affecting neural differentiation, did not induce any change in the integrin assessment. Messenger-RNAs for the two alpha 6 isoforms, A and B, were present in both cell lines. However, in LAN-5 cells, the protein product was neither detectable nor inducible by differentiation. Our results confirm the specific modulation of the alpha 1 beta 1 integrin expression in human neuronal development, and show, for the first time, the involvement of alpha 2 beta 1 and alpha 3 beta 1 heterodimers in this maturational process.
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PMID:Modulation of alpha 1 beta 1, alpha 2 beta 1 and alpha 3 beta 1 integrin heterodimers during human neuroblastoma cell differentiation. 769 64

Recent work on a variety of normal and malignant cell lines has shown that induction and secretion of biologically active TGF-beta may occur after exposure to all-trans-retinoic acid (RA), coincident with decreased growth rate and/or differentiation. This study evaluates the expression and regulation of transforming growth factor beta (TGF-beta) and its receptors during RA-induced cell growth arrest and induction of differentiation in the RA-sensitive human neuroblastoma cell line SMS-KCNR and the RA-resistant neuroblastoma cell line SK-N-AS. RA treatment of SMS-KCNR cells results in a 40-fold increase in TGF-beta 1 mRNA after 4 days of RA, a dose-dependent increase in TGF-beta 1 secretion, an increase in types I (TBRI) and III (TBRIII) TGF-beta receptor proteins, and an increase in type II TGF-beta receptor (TBRII) mRNA coincident with RA-responsiveness of the cells. However, in the RA-resistant line SK-N-AS, TGF-beta 1 is constitutively secreted at levels that are unchanged after RA treatment, and although TBRI and TBRIII mRNA is expressed in untreated SK-N-AS cells, levels of TBRI and TBRIII protein and TBRII mRNA decrease after RA treatment. Thus, in RA-sensitive neuroblastoma cells, RA treatment may result in the induction of a negative autocrine TGF-beta 1 growth regulatory loop. These results suggest the hypothesis that: (a) induction of a TGF-beta 1 negative autocrine growth loop may be a necessary component for RA-responsiveness of neuroblastoma cells in vivo; and (b) the inability to induce or maintain this TGF-beta 1 negative autocrine growth loop may be a mechanism of RA resistance in neuroblastoma.
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PMID:Induction of transforming growth factor beta 1 and its receptors during all-trans-retinoic acid (RA) treatment of RA-responsive human neuroblastoma cell lines. 775 90

beta-Amyloid peptide (A beta), a proteolytic fragment of the beta-amyloid precursor protein, is a major component of senile plaques in the brain of Alzheimer's disease patients. This neuropathological feature is accompanied by increased neuronal cell loss in the brain and there is evidence that A beta is directly neurotoxic. In the present study reduced cell viability in four different neuroblastoma cell types was observed after treatment with human A beta 1-42 for 1 day. Of the cell types tested rat PC12 and human IMR32 cells were most susceptible to A beta toxicity. Chromosomal condensation and fragmentation of nuclei were seen in PC12, NB2a, and B104 cells but not in IMR32 cells irrespective of their high sensitivity to A beta. Electrophoretic analysis of cellular DNA confirmed internucleosomal DNA fragmentation typical for apoptosis in all cell types except IMR32. These findings suggest that the form of A beta-induced cell death (necrosis or apoptosis) may depend on the cell type.
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PMID:Apoptotic cell death induced by beta-amyloid 1-42 peptide is cell type dependent. 779 Aug 74


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