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)

Retinoic acid (RA) has been shown to induce the differentiation of human neuroblastoma cells in vitro. In this study, we describe two variants of the SK-N-SH human neuroblastoma cell line that have dramatically different responses to RA. RA induces neuronal-like differentiation characterized by extensive neurite outgrowth, thick neurite bundles, and large cellular aggregates of SK-N-SH-N (SH-N) cells. In contrast, RA treatment of SK-N-SH-F (SH-F) cultures transforms the small neuroblast cells into large flattened, fibroblastic or epithelial-like cells. Karyotype analysis verified that the SH-N and SH-F cultures were derived from a common precursor cell. Confirmation of their markedly different responses to RA was obtained by metabolic labelling of glycoproteins and SDS-PAGE analysis. While both sublines showed very similar Coomassie-labelled protein bands and glycoprotein profiles in control cultures, dramatic differences between the lines were revealed following RA treatment. In contrast to their similar protein profiles, untreated SH-N and SH-F cells had quite different patterns of ganglioside biosynthesis in that GM3 was detected in SH-F cells but not in SH-N, while GM1 was only detected in SH-N. Cellular RA binding protein (CRABP) was detected in both SH-F and SH-N cells and their RA-transformed derivatives. These results demonstrate heterogeneity in the response to RA of neuroblastoma cells derived from a common origin that cannot be accounted for by differences in CRABP content. The SH-N and SH-F neuroblastoma sublines should provide a useful system for further studies of the molecular processes through which RA exerts its differentiation-inducing activity on this type of tumor.
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PMID:Retinoic acid-induced differentiation of human neuroblastoma: a cell variant system showing two distinct responses. 302 62

High activity of angiotensin-converting enzyme was demonstrated in human neuroblastoma tissue. This activity required the presence of chloride ion and was almost completely inhibited by a specific converting enzyme inhibitor captopril (10 nM), indicating that the activity measured is indeed angiotensin-converting enzyme. Furthermore, the biochemical features of the enzyme were closely similar to the well-known properties of human lung converting enzyme, such as molecular weight (290,000), optimum pH (8.0-8.5), the presence of glycoprotein residues, and dependence on chloride ion concentration. These results provide definitive evidence for the presence of true angiotensin-converting enzyme in human neuroblastoma tissue.
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PMID:Biochemical characterization of angiotensin-converting enzyme in human neuroblastoma tissue. 303 87

To study the properties of protein-bound oligosaccharides in neuronally differentiating cells, two model systems were used: murine N1E-115 and N-18 neuroblastoma cells inducible by serum starvation and rat PC12 pheochromocytoma cells inducible by nerve growth factor. Glycopeptides were prepared from cells metabolically labeled with [3H]glucosamine and analyzed by gel filtration. The properties of the high-molecular-weight glycopeptides were studied using enzymatic digestion with neuraminidase and endo-beta-galactosidase. In contrast to other cell lines analyzed, the neuroblastoma and pheochromocytoma lines contained predominantly glycopeptides completely cleavable with endo-beta-galactosidase, which indicated that they were linear-type poly-N-acetyllactosamine glycans. The proportion of these linear chains in the high-molecular-weight fraction increased during neuronal differentiation in both cell systems. The linear nature of the glycans was also correlated with positive anti-i and negative anti-I reactivity of the cells in immunofluorescence microscopy. Specific cell surface labeling for poly-N-acetyllactosamine glycans and sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed several glycoprotein components, some of which showed changes during neuronal differentiation. The high proportion of linear poly-N-acetyllactosamine chains in these neuronal cell lines and its increase during neuronal differentiation suggests that these glycans may be a characteristic feature of neuronal or neuronally differentiating cells.
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PMID:Poly-N-acetyllactosamine glycans of cellular glycoproteins: predominance of linear chains in mouse neuroblastoma and rat pheochromocytoma cell lines. 330 6

In order to develop a molecular probe to delineate chemical and biological characteristics of human neuroblastoma cells, a murine monoclonal antibody (Mab 5G3) was produced that is directed to a glycoprotein, preferentially expressed on the surface of such cells. This antibody is of IgG2a isotype, has an association constant of 8 X 10(9) M-1, and reacts preferentially with human neuroblastoma cell lines and fresh frozen tissue sections in enzyme-linked immunosorbent assay and immunoperoxidase assays, respectively. Minimal reactivity is observed with a variety of lymphoblastoid cell lines and normal fetal and adult tissues. Mab 5G3 specifically recognizes a neuroblastoma target glycoprotein antigen of 215 kDa that is derived from a 200-kDa precursor, as evident from pulse-chase biosynthetic studies. Treatment with tunicamycin revealed that both molecules contain N-asparagine-linked oligosaccharides; however, only the 215-kDa species is resistant to treatment with endo-beta-N-acetylglucosaminidase H and sensitive to neuraminidase, indicating that it contains trimmed and terminally sialylated oligosaccharides of the "complex" type. In contrast, the 200-kDa precursor is sensitive to endo-beta-N-acetylglucosaminidase H and resistant to neuraminidase treatment indicating that it contains high-mannose non-processed oligosaccharides. The 215-kDa molecule is sulfated, phosphorylated at serine residues, and expressed on the cell surface. A molecule of 200 kDa is detected by Mab 5G3 in spent culture medium of human neuroblastoma cells which is neither sulfated nor phosphorylated.
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PMID:Characterization of a unique glycoprotein antigen expressed on the surface of human neuroblastoma cells. 352 41

The neural cell adhesion molecule (N-CAM) has been implicated in morphogenetic events during formation of the nervous system. Three forms of N-CAM exist, all glycoprotein chains, of relative molecular masses 180,000 (180K), 140K and 120K (N-CAM180, N-CAM140 and N-CAM120) which are differentially expressed on neural cell types and during development. The three chains are thought to carry similar if not identical amino-acid sequences on their extracellular amino-terminal domains, but differ in the length of their carboxy-terminal cytoplasmic region. They occur in highly sialylated embryonic and less sialylated adult forms. N-CAM180 is selectively expressed in more differentiated neural cells and may play a role in the stabilization of cell contacts. To investigate this, we have studied in the surface membrane of a mouse neuroblastoma cell line N2A the lateral mobility of the two predominant forms of N-CAM, N-CAM180 and N-CAM140, as a function of differentiation. Here we report that as judged by fringe pattern photobleaching, the surface mobility of N-CAM140 is higher than that of N-CAM180, suggesting an association of N-CAM180 with the cytoskeleton or other stabilizing factors. We also show that brain spectrin, a membrane-cytoskeleton linker protein, binds only to N-CAM180. The immobilization of N-CAM in differentiated N2A cells is achieved by a shift in expression from N-CAM140 to N-CAM180.
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PMID:Differentiation state-dependent surface mobilities of two forms of the neural cell adhesion molecule. 353 9

In order to screen human tumor cells for putative cell surface marker molecules, the glycoprotein composition of in vitro cultivated human tumor cell lines of different origin (12 carcinomas, one neuroblastoma, one melanoma and one sarcoma) was analyzed by metabolically labelling the cells with [3H]galactose, [3H]mannose and [3H]fucose and subsequently separating the labelled material by SDS-PAGE. The cell lines expressed their specific glycoprotein patterns. Strongly glycosylated proteins of apparent mol. wt 40-45 kD, 60-62 kD, 80-82 kD and 90-92 kD were shared by nearly all carcinoma cell lines studied. Apart from these glycoprotein clusters, a great diversity was observed between tumor cell lines derived from the same organ. Three bladder carcinoma cell lines had a 112-114 kD glycoprotein in common. Glycoprotein expression of these cell lines remained constant during 1 yr of in vitro culture. Hence, these glycoprotein patterns seem to be useful for monitoring the phenotypic stability of cell lines. A sarcoma cell line was deficient in incorporating fucose and showed strikingly different glycoprotein patterns compared to the other cell lines studied. The metabolic labelling procedure revealed a wide phenotypic heterogeneity of the human carcinoma cell lines concerning glycoprotein synthesis. This method contributes another parameter to map the major glycoprotein species of various types of carcinomas.
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PMID:Heterogeneity of glycoprotein synthesis in human tumor cell lines. 370 97

We have used serologic, biochemical, and genetic methods to characterize two stage-specific human differentiation antigens of neural and melanocytic cells: A42 (57,000 Mr glycoprotein) and J143 (140,000/30,000 Mr glycoprotein). The genes determining A42 and J143 cell surface expression in rodent-human hybrids were chromosomally mapped, and the respective human chromosomes were introduced into rodent cells derived from distinct differentiation lineages. Serologic analysis of the resulting hybrid clones has permitted the identification of two types of regulatory signals determining A42 and J143 expression. First, both antigens are expressed in hybrids constructed with antigen-positive human cells and also in certain hybrids constructed with antigen-negative human cells, indicating that intrinsic signals provided by the differentiation program of the rodent fusion partner induce antigen expression. Second, a series of human-mouse neuroblastoma hybrids, which are A42- or J143- when cultured on plastic surfaces, can be induced to express the antigens when cultured on substrates coated with extracellular matrix (ECM) produced by bovine corneal endothelial cells or fibronectin. This induction of antigen expression by extrinsic, ECM-derived signals is accompanied in the neuroblastoma hybrids by increased substrate adhesiveness and cell spreading and by characteristic changes in cell morphology. A similar program of phenotypic changes is also seen in spontaneous variants of human neuroblastoma and Ewing's sarcoma cells and in ECM-induced Ewing's sarcoma cells. These findings suggest that ECM-derived signals have a role analogous to mitogens and soluble differentiation factors in modulating differentiation phenotypes and tissue-specific patterns of cell surface antigen expression.
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PMID:Extracellular matrix-modulated expression of human cell surface glycoproteins A42 and J143. Intrinsic and extrinsic signals determine antigenic phenotype. 377 96

A cell-surface receptor for the mammalian reovirus type 3 hemagglutinin was isolated by using antiidiotypic anti-receptor antibodies. The receptor is a glycoprotein with a molecular mass of 67,000 daltons and a pI of 5.9. Evidence that the isolated structure represents the reovirus receptor was obtained by electrophoretic immunoblot studies, which demonstrated that the 67,000-dalton glycoprotein is the only cell-surface structure recognized by both reovirus type 3 and the anti-receptor immunoglobulin. Comparison of the reovirus receptor on murine thymoma (R1.1) and rat neuroblastoma (B104) cells indicated that similar structures on the cell surface are recognized by the reovirus type 3 and the anti-receptor antibodies as previously suggested from cellular and binding studies. This receptor was found on mouse, rat, monkey, and human cells. Furthermore, diverse tissue types, including lymphoid and neuronal cells, express the receptor structure. The receptor structure is discussed in terms of its role in mediating viral tropism and as an essential cell-surface protein.
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PMID:Isolation and biochemical characterization of the mammalian reovirus type 3 cell-surface receptor. 387 49

The rodent neural cell adhesion molecule (N-CAM) consists of three glycoprotein chains of 180, 140, and 120 kD in their adult forms. Although the proportions of the three components are known to change during development and differ between brain regions, their individual distribution and function are unknown. Here we report studies carried out with a monoclonal antibody that specifically recognizes the 180-kD component of mouse N-CAM (N-CAM180) in its highly sialylated embryonic and less glycosylated adult forms. In primary cerebellar cell cultures, N-CAM180 antibody reacts intracellularly with all types of neural cells including astrocytes, oligodendrocytes, and neurons. During cerebellar, telencephalic, and retinal development N-CAM180 is detectable by indirect immunohistology in differentiated neural cells, but, in contrast to total N-CAM, not in their proliferating precursors in the ventricular zone and primordial and early postnatal external granular layer. In monolayer cultures of C1300 neuroblastoma cells, N-CAM180 appears by immunofluorescence more concentrated at contact points between adjacent cells, while N-CAM comprising the 180- and 140-kD component shows a more uniform distribution at the plasma membrane. Treatment of neuroblastoma cells with dimethylsulfoxide, which promotes differentiation, induces a shift toward the predominant expression of N-CAM180. These observations support the notion that N-CAM180 is expressed selectively in more differentiated neural cells and suggest a differential role of N-CAM180 in the stabilization of cell contacts.
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PMID:Selective expression of the 180-kD component of the neural cell adhesion molecule N-CAM during development. 390 57

The protective capacity of antiviral antibodies has generally been considered to depend on their interactions with structural components of the virion. Here we report protection against lethal 17D yellow fever virus (YF) encephalitis of mice by passive administration of nonneutralizing monoclonal antibodies to a 17D YF-specified nonstructural glycoprotein, gp48, and by active immunization with purified gp48. Among five anti-gp48 monoclonal antibodies tested, two with high titer complement-fixing (CF) activity were protective, whereas three antibodies with little or no CF activity were not. The ability of antibodies to protect correlated with their ability to promote complement-mediated cytolysis (CMC) of 51Cr-labeled 17D YF-infected mouse neuroblastoma (Neuro 2a) cells. Purified gp48, prepared from lysates of 17D YF-infected Vero cells by immunoaffinity chromatography, was shown to bear both YF type-specific and flavivirus group-reactive determinants in a solid phase radioimmunoassay. Immunization of mice with purified gp48 resulted in solid protection in the absence of detectable anti-virion antibody, measured by neutralization and radioimmunoprecipitation assays. The results are consistent with plasma membrane expression of gp48 and susceptibility of 17D YF-infected neural cells to CMC, a possible mechanism of host defense in 17D YF encephalitis. Protection provided by immunization with gp48, which bears a group-reactive determinant and is highly conserved among flaviviruses, may have implications in regard to flavivirus vaccine design.
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PMID:Protection against 17D yellow fever encephalitis in mice by passive transfer of monoclonal antibodies to the nonstructural glycoprotein gp48 and by active immunization with gp48. 403 1


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