Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017638 (glioma)
 30,880 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Addition of 1 micronM 1-norepinephrine to cultures of C6TK- rat glioma cells caused a 2-fold increase in specific activity of the glial-specific enzyme 2':3'-cyclic nucleotide 3'-phosphohydrolase (nucleoside-2':3'-cyclic-phosphate 3'-nucleotidohydrolase, EC 3.1.4.16). Specific activity could also be stimulated by analogues of 3':5'-cyclic AMP, and the effect of norepinephrine could be blocked by beta-adrenergic receptor antagonists but not by alpha-adrenergic antagonists. Norepinephrine or cyclic AMP analogues also increased the specific activity of this enzyme in other clones of glioma and Schwannoma cells and in glioma X neuroblastoma cell hybrids. These results show that the stimulatory effect of norepinephrine on cyclic AMP concentrations in glioma cells leads ultimately to a stimulation of glial-specific cell funtion.
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PMID:Norepinephrine induces glial-specific enzyme activity in cultured plasma glioma cells. 20 Sep 19

Two types of nerve growth factor (NGF) receptors have been described: high affinity (class I) and low affinity (class II). Biological responses to NGF are thought to be mediated by class I receptors, whereas the role of class II receptors is less clear. While some neuronal cells express both receptor types, only class II receptors have been detected on glial cells. Two glial cell lines, peripheral Schwannoma D6P2T and central 33B glioma cells, were employed to investigate the properties of class II receptors in the absence of class I receptors. These cell lines were found to express NGF receptors identified as class II by a low nanomolar dissociation constant, rapid dissociation kinetics at 4 degrees C, and trypsin sensitivity. The receptor was found to bind brain-derived neurotrophic factor with similar affinity as NGF. The responsible binding molecule appeared in sodium dodecyl sulfate-polyacrylamide gel electrophoresis as a heterogeneously glycosylated protein of 60-80 kDa with a tendency to aggregate. All receptor bands affinity-labeled with radioiodinated NGF were immunoprecipitated with anti-p75NGFR antibody, but not with anti-p140prototrk antiserum. In these cells, which express p75NGFR as only NGF receptor, a time- and temperature-dependent appearance of a nondisplaceable, trypsin-resistant, acid wash-stable ligand fraction, followed by an increase of trichloroacetic acid-soluble radiolabel in the medium was observed. This sequestration resembled receptor-mediated internalization with subsequent degradation of NGF. Whether this ligand processing indicates a functional role of p75NGFR in glial cells remains to be shown.
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PMID:Nerve growth factor (NGF) receptor on rat glial cell lines. Evidence for NGF internalization via p75NGFR. 132 Nov 30

Utrophin, the autosomal dystrophin-related protein (DRP), is expressed in HeLa cells, smooth muscle-like BC3H1 cells from mouse brain, COS monkey kidney cells, the P388D1 monocyte-macrophage cell line and untransformed human skin fibroblasts, as well as in rat C6 glioma and Schwannoma cells. It was undetectable, however, in the Sp2/O mouse myeloma cell line and in hybridoma lines derived from it. Dystrophin was not detected in any of these cell lines. Although all utrophin-containing cells were capable of forming monolayers in culture, no major effects of either attachment to substratum or length of time in culture (2-17 days) on utrophin levels were observed. After subcellular fractionation of BC3H1 or glioma cells, nearly all of the utrophin was found in the Triton-soluble fraction, suggesting an association with cell membranes.
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PMID:Utrophin, the autosomal homologue of dystrophin, is widely-expressed and membrane-associated in cultured cell lines. 142 62

Two cases of stereotactically induced and spontaneously metastasizing neoplasms in the rat and the cat brain are reported. In the rat, a malignant Schwannoma derived from initially supratentorially implanted RN6 cells developed a second tumor in the posterior cranial fossa. In the cat, a highly malignant polymorphous anaplastic glioma induced by implantation of cloned rat glioma cells (F98) into the left internal capsule developed small tumor cell nests along the ependyma of the ipsilateral ventricle. In precontrast magnetic resonance imaging (MRI) of both cases, the primary tumor was detectable only by a very weak hypointensity and through a shift of the midline. No metastases were apparent. Application of the metallated paramagnetic porphyrin derivative manganese(III) tetraphenylporphine sulfonate (MnTPPS) resulted in a remarkable contrast enhancement between tumoral and normal tissue, which was evident not only in the primary tumor but also in the small metastases. These observations demonstrate for the first time that MnTPPS is an efficient MRI contrast agent for the detection of metastases from primary brain neoplasms and, in consequence, support the hypothesis of its selective binding to tumor cells.
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PMID:Identification of intracranial liqor metastases of experimental stereotactically implanted brain tumors by the tumor-selective MRI contrast agent MnTPPS. 150 24

The immunohistochemical distribution of alpha and beta subunits of S-100 protein (S-100 alpha, S-100 beta, respectively) in 138 cases of human brain tumors was investigated by the avidin-biotin immunoperoxidase method. Brain tumors can be divided into four groups: group 1 [S-100 alpha (+) and/or S-100 beta (+)]; astrocytoma, glioblastoma, ependymoma, subependymoma, oligodendroglioma, choroid plexus papilloma, gangliocytoma, meningioma, chordoma, malignant melanoma. Group 2 [S-100 alpha (+) and S-100 beta (-)]; pineoblastoma, pituitary adenoma, craniopharyngioma, rhabdomyosarcoma. Group 3 [S-100 alpha (-) and S-100 beta (+)]; acoustic Schwannoma. Group 4 [S-100 alpha (-) and S-100 beta (-)]; medulloblastoma malignant lymphoma, germinoma. The S-100 beta immunoreactivity pattern in brain tumors was similar to those obtained using conventional anti-S-100 protein sera. In the first group of brain tumors both the number of positively stained tumor cells and the staining intensity were generally greater for S-100 beta than for S-100 alpha with a few exceptions including one gemistocytic astrocytoma, one subependymoma, one malignant melanoma, and some cases of glioblastomas. As to the relationship between malignancy and S-100 protein in glioma, S-100 beta immunoreactivity decreased according to degree of malignancy, while that of S-100 alpha varied, suggesting a heterogeneity of tumor cells in glioblastomas. Immunostaining for S-100 alpha and S-100 beta might become a useful diagnostic procedure in brain tumors and may give us more detailed and precise data of S-100 protein in brain tumors.
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PMID:Immunohistochemical study on the distribution of alpha and beta subunits of S-100 protein in brain tumors. 188 40

Two kinds of novel neural trophic factors were currently detected in von Recklinghausen neurofibroma (NF1) extracts. One of the two was a growth factor, neuroblastoma growth factor (Mr less than 5 kDa), which promotes the proliferation of human neuroblastoma cell and survival and neurite-extension of rat cortical neurons, but differently from nerve growth factor (NGF) or NGF-like factors. The other one was a glial growth inhibitor (Mr = 100 kDa), which suppresses the growth of glioma cell lines, astrocytoma, glioblastoma, oligodendroglioma and Schwannoma. These factors do not appear to be previously identified cytokines or growth factors such as interleukins, granulocyte colony-stimulating factor, NGF and fibroblast growth factor. There was also detectable ciliary neurotrophic factor-like activity in the extracts. The primary cause of high contents of these factors in NF1 is not known, but may relate to fundamental mechanisms controlling growth and differentiation of neurons and glias during development of nervous system.
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PMID:von Recklinghausen neurofibroma produces neuronal and glial growth-modulating factors. 193 68

In this study, we have investigated the expression of the neural cell adhesion molecule (NCAM) in the human brain, primary brain tumours and neuroblastoma. Adult brain was found to express discrete isoforms of 180, 170, 140 and 120 kDa, which on neuraminidase treatment resolved into bands of 180, 170, 140, 120 and 95 kDa. Primary brain tumours such as Schwannoma and medulloblastoma expressed embryonic NCAM characterised by a high level of glycosylation, whereas other tumours, e.g. astrocytoma, meningioma, glioma and oligodendroglioma expressed adult NCAM. Post-neuraminidase treatment, differential expression of the 180, 170, 140, 120 and 95 kDa isoforms were noted in these various tumour types. On the other hand, neuroblastoma cell lines were found to express only embryonic NCAM, which after neuraminidase treatment resulted in differential presence of only 180, 140 and 120 kDa proteins.
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PMID:Expression of the cluster 1 antigen (neural cell adhesion molecule) in neuroectodermal tumours. 203 10

Glucocorticoid hormones affect gene expression directly at the level of transcription via intracellular receptors that translocate to the nucleus in the presence of steroid. In the brain, two types of high-affinity receptors bind glucocorticoids, the type I, mineralocorticoid receptor and the type II, glucocorticoid receptor (GR). Both receptor types are expressed by many types of neurons. Although binding studies have suggested that glial cells may also express receptors, the expression of these receptors in specific classes of glia has not been studied previously. This immunocytochemical study was undertaken to determine which of the different classes of glial cells express type II GR. Primary cultures of mixed glial cells from rat cerebrum and cerebellum, purified oligodendrocytes and astrocytes, as well as two glial tumor cell lines were screened for the expression of glucocorticoid receptors using a mouse monoclonal antibody directed against rat liver GR (BuGR-2). Glial cell types were identified by morphology and immunoreactivity (IR) with antibodies directed against glial fibrillary acidic protein (GFAP), cyclic nucleotide phosphodiesterase (CNP), or myelin basic protein (MBP). Double immunofluorescence microscopy revealed that all GFAP-IR cells (type 1 and type 2 astrocytes), all CNP- or MBP-IR cells (oligodendrocytes), as well as immature and intermediate cell types expressed GR, although at different levels. C6 glioma and JScl1 Schwannoma cells were observed to express moderate to high levels of GR. Furthermore, cells grown in the absence of glucocorticoids had diffuse GR staining over the cytoplasm, whereas cells grown in the presence of the synthetic glucocorticoid dexamethasone had strong nuclear staining. These results demonstrate that, in vitro, all classes of glial cells express glucocorticoid receptors that can translocate to the nucleus in the presence of hormone. These observations suggest that glial cells are major targets for glucocorticoid-directed control of gene transcription in the nervous system.
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PMID:Type II glucocorticoid receptors are expressed in oligodendrocytes and astrocytes. 209 80

Adrenal chromaffin cells from early postnatal rats maintained in culture have previously been shown to grow neuritic processes and survive better in the presence of nerve growth factor (NGF). In the present study we have quantitated the effects on chromaffin cell (postnatal day (D) 8) survival and neurite outgrowth of: NGF, ciliary neuronotrophic factor (CNTF), activities contained in various types of conditioned media (CM), and various substrata (laminin, fibronectin and polyornithine-binding neurite-promoting factor from RN 22 Schwannoma cells - PNPF). At saturating concentrations CNTF (50 ng/ml) and C6 glioma cell CM, (50-fold concentrated) supported survival over the 4-day culture period of all the chromaffin cells present in culture 2 h after seeding. NGF (50 ng/ml) and the non-concentrated CMs from primary Schwann cell and astrocytes as well as Schwannoma and C6 glioma cell cultures, achieved the maintenance of only about half the number of cells above the baseline survival as compared to CNTF and the concentrated C6-CM. These results are compatible with two subsets of D8 chromaffin cells, one only supported by CNTF and the concentrated CM and the other supported by either NGF or CNTF. Either NGF or CNTF elicited neurite outgrowth from 15-20% of the surviving cells. Combination of maximal doses of NGF and CNTF caused a small increase in neurite recruitment beyond that elicited by either factor alone. Low doses of CNTF added to the effect of NGF, shifting the NGF titration curve by about 4-fold. Neurite outgrowth was also induced by the concentrated, but not the unconcentrated C6-CM. Laminin, fibronectin and PNPF did not affect the fibronectin and PNPF did not affect the recruitment of neurites as compared to a polyornithine substratum unless the cultures were supplemented with a neuronotrophic factor and carried for 7 days. However, even before showing effects on neurite recruitment these substrata affected various neuritic performances, such as length, neurite numbers and endings per cell.
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PMID:Neuronotrophic and neurite-promoting factors: effects on early postnatal chromaffin cells from rat adrenal medulla. 398 81

The monoclonal antibody 217c, raised by Peng et al. [(1982) Science, Wash. 215, 1102-1104] in mice against the rat glioma cell line C6, can be used as a marker for normal Schwann cells. In mixed cultures of Schwann cells and fibroblasts from neonatal rat sciatic nerve, this monoclonal antibody, detected by indirect immunofluorescence, bound to the surface of cells with the same elongated morphology as those that express a previously described surface antigen, rat neural antigen-1 (Ran-1), defined by polyclonal mouse antisera. In these experiments Ran-1 and the antigenic determinant recognized by monoclonal 217c were both found on normal rat Schwann cells and on the rat glial tumor cell lines C6, 33B and 21A and the pheochromocytoma PC12. Neither anti-Ran-1 nor the monoclonal antibody bound to neurons, fibroblasts or glial cells in newborn rat cerebellum cultures, the rat muscle cell line L6, the transformed rat fibroblast cell line Rat 1, the rat brain tumor cell line B28 or the mouse Schwannoma cell line TR6B. Thus the monoclonal 217c behaved as if it were detecting Ran-1 by binding to normal rat Schwann cells and to those tumor cells that have this antigen. Our data show that this monoclonal antibody is a reliable and convenient marker for rat Schwann cells in culture.
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PMID:A monoclonal antibody equivalent to anti-rat neural antigen-1 as a marker for Schwann cells. 406 57


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