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)

Immunostaining patterns of glial fibrillary acidic protein (GFAP), S-100 protein (S-100p) and vimentin were studied using immunohistochemical techniques on 48 paraffin embedded glial tumors. GFAP was positive in all tumor cases except in two oligodendrogliomas. S-100p was found in most astroglial tumors and in half of the oligodendrogliomas. Vimentin was positive in many astrocytomas but in no oligodendrogliomas. Most astroglial tumors showed similar immunoreactivity for GFAP and S-100p. Fibrillary processes, however, showed stronger and more crisp staining with anti-GFAP than with anti-S-100p, whereas cell nuclei were labeled only for S-100p. Vimentin was localised mainly in juxtanuclear positions. In many astrocytomas with different degrees of malignancy co-expression of GFAP, S-100p and vimentin was found. The presence of GFAP and S-100p was not correlated with the degree of differentiation in astrocytomas. Vimentin was more positive in anaplastic astrocytomas but this finding was not statistically significant. It seems that GFAP is a superior marker to S-100p and vimentin in the identification of human gliomas.
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PMID:An immunocytochemical comparison of glial fibrillary acidic protein, S-100p and vimentin in human glial tumors. 231 88

We examined the effect of lactic acid on cultured human glioma cell lines expressing glial fibrillary acidic protein (GFAP), vimentin and neuron-specific enolase (NSE). The growth of the cells was inhibited by the lactic acid in a dose-dependent manner. At 56 mM of lactic acid, the surviving cells of the KNS-42-c2 cell line developed slender processes and increasingly formed bizzar giant cells. In an immunofluorescence study of the lactic acid-resistant cells, the GFAP-positive cells prominently decreased in number, while the NSE-positive cells clearly increased. The vimentin was not affected throughout the experiment. After removing lactic acid from the medium, the GFAP-positive cells gradually increased in number. The method of dot immunoassay was useful for quantifying GFAP in cellular extracts. It indicated that the amount of GFAP decreased in the cells cultured with lactate-containing media and increased to the primary values after removing the lactic acid. These results may suggest that the morphological and immunochemical diversities of glioma cells are secondarily affected by cellular microenvironments such as lactic acid.
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PMID:Contrary effect of lactic acid on expression of neuron-specific enolase and glial fibrillary acidic protein in human glioma cells. 232 50

Long term in vitro cultures of six human malignant gliomas were established to obtain permanent lines and to assess, under conditions of prolonged culture, changes in morphology and phenotype of neoplastic cells and the extent of these modifications. We analyzed expression of the following markers by immunocytochemistry: glioma-specific antigens (GE2 and CG12), fibronectin, intermediate filaments (GFAP, vimentin, neurofilaments), class I and II histocompatibility antigens (HLA-ABC and HLA-DR), growth factor and receptor (alpha TGF and EGF-receptor), proliferation-associated antigen (Ki-67). Strong and stable staining with the two antiglioma monoclonal antibodies (GE2 and CG12) was seen, with coexpression of GFAP and fibronectin in five of six cell lines (after 20 passages) and presence of vimentin and neurofilaments. HLA-DR expression was heterogeneous, with a peculiar intracellular compartmentation in four of six cell lines. Cells showed clear cytoplasmic positivity for alpha TGF and strong membrane staining for EGF-receptor. In previous studies we showed that these cell lines have increased copies of chromosome 7; therefore we speculate that an autocrine pathway of stimulation may maintain the neoplastic growth. The percentage of Ki-67 positive proliferating cells ranged from 40 to greater than 60%, depending on cell line and passage. A slight decrease in the positivity of some markers (GFAP, vimentin and HLA-DR in 2/6 cell lines) was observed after prolonged in vitro culture (greater than 12 months), but morphophenotypic modifications, established within a few passages after explanation, were maintained with time. A clonogenic assay showed values of plating efficiency (PE) higher than corresponding values of other similar cell lines with a tendency to increase in the late passages. PE and Ki-67 positivity were not associated with tumorigenicity into nude mice (except the Hu 197 cell line). These results indicate that, in culture, all six cell lines acquired stable morphology, a well defined antigenic phenotype and high growth rate. Further studies will be performed on these permanent cell lines to clarify differentiation steps of malignant gliomas.
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PMID:Morphological heterogeneity and phenotype modifications during long term in vitro cultures of six new human glioblastoma cell lines. 233 Jun 9

The cytoskeleton (CSK) of eukaryotic cells is composed of a complex interconnected network of filaments which is important in a wide variety of cellular functions including changes in cell shape, cell motility, mitosis, anchorage-dependent growth, and the localization of cellular organelles such as mitochondria, polyribosomes, and secretory granules. The various proteins comprising the cytoskeleton include actin in microfilaments, tubulin in microtubules, and the heterogeneous group of intermediate filament proteins that are associated with different cell types (keratin in epithelial cells, vimentin in fibroblasts, desmin in muscle cells, glial filament protein in glial cells, and the neurofilament protein subunits in neural tissue). Many other proteins in glial cells, and the neurofilament protein subunits in neural tissue). Many other proteins are closely associated with the cytoskeleton and influence its organization. In neoplastic cells, the expression of these different CSK proteins, especially the intermediate filament proteins, reflects their morphologic and functional differentiation. The carcinomas contain keratin; identification of individual keratin components may allow further sub-classification of carcinomas which is consistent with their tissue of origin. The sarcomas of muscle origin contain desmin. Vimentin is found primarily with cells of mesenchymal origin, but may coexist with other intermediate filament proteins in other tumors. One example is the coexistence of keratin and vimentin in tumors, such as mesotheliomas, which are derived from epithelial cells of embryonic origin. Glial fibrillary acidic protein is the most specific marker for glial tumors. Tumors of neural origin are characterized by the presence of neurofilament subunits. Therefore, analysis of CSK composition would be useful in diagnosis of clinical specimens and aid in studies of lineage relationships of neoplasms. Although no consistent differences in cytoskeletal structure between neoplastic and normal cells have been identified so far, the presence of more subtle biochemical alterations in the cytoskeletal structure of neoplastic cells that contributes to malignant behavior has not been ruled out. Since the cytoskeletal network plays an important role in cell shape and cell locomotion, which in turn are thought to be involved in growth control, invasion, and metastasis, further work is directed at identifying the various alterations in cytoskeletal architecture that may influence the malignant behavior of neoplastic cells.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Cytoskeleton-associated proteins: their role as cellular integrators in the neoplastic process. 241 18

The peroxidase anti-peroxidase technique was used for localization of glial fibrillary acidic protein (GFAP) and vimentin (VM) in 19 ependymal tumors in order to determine if a unique pattern of intermediate filament (IF) expression could be demonstrated. Cytokeratin (CK) immunoreactivity was examined in a subgroup of 7 tumors with papillary pattern. Nineteen non-ependymal neuroectodermal tumors were used as controls. Ependymomas, subependymomas and astrocytomas were positive for both IF. Oligodendrogliomas, oligodendroglial portions of mixed gliomas and the majority of medulloblastomas were negative for GFAP and VM. Areas of poor differentiation in all tumors demonstrated little expression of any IF. A composite ependymoma/choroid plexus papilloma showed the presence of GFAP, VM and CK in the papillomatous portion only. Four papillary ependymomas were negative for CK. This study emphasizes the parallel distribution of GFAP and VM in well differentiated ependymomas and other glial tumors and casts doubt upon the concept of VM as a marker for de-differentiation in neuroectodermal neoplasia.
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PMID:Immunocytochemical analysis of intermediate filaments in human ependymal tumors. 245 16

Intermediate filament proteins are cytoskeletal components in most vertebrate eukaryotic cells and some of these proteins are recognized markers of cell differentiation. To investigate the expression of intermediate filament proteins of the S-phase cells in human glial tumors, we have examined fourteen patients with benign and malignant gliomas by immunohistochemical study using in vivo labeling with bromodeoxyuridine (BrdU). Five glioblastoma multiforme, five anaplastic astrocytoma, three fibrillary astrocytoma and one gemistocytic astrocytoma were studied. All patients were given intravenous infusion of BrdU (10 mg/kg) one hour before craniotomy for labeling the S-phase cells of the tumors. Surgical specimens were immersed in 70% ethanol, and embedded in paraffin. Four micron sections were immunostained with anti-BrdU monoclonal antibody (Mab) and anti-vimentin Mab by avidin-biotin complex (ABC) method, and anti-glial fibrillary acidic protein (GFAP) serum by peroxidase-antiperoxidase (PAP) method. All sections (except for case 4) were double-labeled with anti-BrdU Mab and anti-GFAP serum, or with anti-BrdU Mab and anti-vimentin Mab. The population of BrdU-labeled cells (i.e. S-phase cells), and double-labeled cells were analyzed. The proportions of BrdU-labeled cells ranged from 6.1% to 17.0% (average 11.1%) in glioblastoma multiforme, from 3.5% to 15.6% (average 8.8%) in anaplastic astrocytoma, and from 2.0% to 2.8% (average 2.5%) in fibrillary astrocytomas. One gemistocytic astrocytoma showed S-phase fraction of 1.7%. Two recurrent cases of anaplastic astrocytoma showed higher S-phase fractions than other non-recurrent cases of anaplastic astrocytoma.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Immunohistochemical study of S-phase cells in human gliomas]. 246 Jan 17

The expression of glial fibrillary acidic protein (GFAP) and vimentin was investigated immunohistochemically in 104 experimental gliomas induced by transplancental application of ethylnitrosourea (ENU) in CDF rats. Immunoreactivity for vimentin was prominent in many astrocytic tumor cells and especially in small glioma cells forming anaplastic medulloblastoma-like foci in many tumors. The majority of tumor cells in oligodendroglial tumors were vimentin negative, except for some of the large polymorphous oligodendrogliomas which contained intermingled vimentin positive glioma cells. GFAP immunoreactivity was detectable only in a low fraction of tumor astrocytes and in a few exceptional cases some oligodendroglial tumor cells stained positive. Immunohistochemistry with antibodies against neurofilaments and cytokeratins revealed no staining in tumor cells of ENU-induced gliomas, while all oligodendrogliomatous tumors stained positive for HNK-1. Immunocytological and immunoblot investigations of the two rat glioma cell clones RG2 and F98, which are both derived from ENU-induced gliomas, showed a prominent expression of vimentin in monolayer cultures and in syngeneic intracerebral transplantation tumors. F98 additionally demonstrated a fraction of GFAP positive cells especially in confluent cultures and in intracerebral tumors. RG2, on the other hand, exhibited virtually no GFAP immunoreactivity in culture but showed individual GFAP positive tumor cells in intracerebral tumors. Our results revealed a more precise picture of the cellular differentiation in ENU-induced rat gliomas and in two widely used glioma cell lines. They underline the heterogeneity of experimental rat gliomas which may comprise cells at different stages of differentiation towards oligodendroglial or astroglial phenotype.
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PMID:Expression of vimentin and glial fibrillary acidic protein in ethylnitrosourea-induced rat gliomas and glioma cell lines. 247 9

Glia-derived nexin (GDN) is a 43 kd cell-secreted protease inhibitor with neurite promoting activity. We have raised specific polyclonal antisera to rat GDN. These antibodies stain a single band at 43 kd on immunoblots of concentrated C6 glioma-conditioned medium and have been used to demonstrate that GDN is present in the olfactory system of the rat. One band at 43 kd is recognized by the GDN antibodies on immunoblots of olfactory bulb homogenate. Immunohistochemistry shows that GDN occurs predominantly in the olfactory nerve layer of the olfactory bulb and in the olfactory submucosa. Comparative studies with antibodies against vimentin, GFAP, and fibronectin suggest that anti-GDN recognizes cells associated with the olfactory system, but not exclusively the olfactory neurons themselves. Data from the immunohistochemical studies were confirmed by RNA blots and GDN mRNA expression throughout development of the olfactory bulb. The high levels of GDN in the rat olfactory system may be related to the continuous degeneration and regeneration phenomena taking place in these structures.
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PMID:Detection of glia-derived nexin in the olfactory system of the rat. 248 98

Tumours were produced in the adult cat brain by injection of the rapidly growing anaplastic rat glioma clone F98 in order to study their neuropathology, pathophysiology, regional biochemistry and magnetic reasonance imaging. We report here the neuropathological behaviour of cell suspensions in the basal ganglia and the left cerebral hemisphere one, two, three, four and six weeks after stereotactic implantation with respect to tumour growth, immunological tumour regression and alterations of the blood-brain barrier with associated vasogenic brain oedema. Injected cell suspensions produce consistently growing tumours during the first, second and third weeks. Tumour sizes varied according to the survival time and were only slightly dependent on the inoculated cell number, i.e., 3 and 6 x 10(6) tumour cells, respectively. Immunohistochemistry with respect to proteins of the cytoskeleton and other cell markers showed positive tumour cell immunoreactions for vimentin and S 100, but not for GFAP, Leu-7, Leu-M1 and MBP. While leucocyte infiltration is apparent after only one week, major tumour regression phenomena develop after three weeks in conjunction with severe lymphocytic reactions of the host, resulting in complete tumour rejection with scar gliosis after four and six weeks, respectively. This transplantation glioma model is accompanied by vasogenic brain oedema both within the tumour area and in the homolateral hemisphere. Immunohistochemistry of serum proteins, i.e. total serum protein, albumin and IgG reveals impairment of the blood-brain barrier after one week, reaching its maximum after two and three weeks. The oedematous changes decrease dramatically after four and six weeks, when most of the serum proteins are reabsorbed by cellular activities in the tumour scar. The vasogenic brain oedema in this xenogeneic glioma transplantation model may be enhanced by the immunological reactions in the brain.
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PMID:Experimental transplantation gliomas in the adult cat brain. 1. Experimental model and neuropathology. 274 39

A series of 146 primary and metastatic neoplasms of the CNS were studied with a panel of monoclonal and polyclonal antibodies. The purpose of the study was to evaluate whether immunohistochemistry can help in the differential diagnosis and facilitate a more precise classification of CNS tumors. Neoplastic cells in glial tumors (astrocytomas, ependymomas, oligodendrocytomas) reacted strongly with GFAP. Immunoreactivity with antibodies to neurofilaments helped to distinguish neuronal tumors. Keratin was always positive in metastatic carcinomas, while vimentin positivity characterized mesenchymal differentiation. Other markers such as LCA, S-100, alpha-1-antichymotrypsin, factor VIII, CEA and EMA were variably expressed by tumor cells providing information about cell differentiation and functional status.
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PMID:The contribution of immunohistochemistry to the differential diagnosis of primary and metastatic neoplasma of the central nervous system (CNS). 275 65


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