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Query: UMLS:C0017638 (glioma)
 30,880 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cultured human glioma cells were studied by double indirect immunofluorescence technique using antisera against intermediate filaments and glial fibrillary acidic protein. With both antisera cytoplasmic fibrillar fluorescence was seen. Perinuclear bundles of intermediate-sized filaments, induced by vinblastine treatment, were strongly stained with both antisera. The degree of codistribution of the two types of antigenic determinants varied considerably from cell to cell. The results suggest that two types of filament-related antigenic determinants can be present in the same cell, and also that glial fibrillary acidic protein-related filaments may possess functional similarities to the intermediate filaments found in other cells. Glial fibrillary acidic protein remains as a useful and specific antigenic marker for the study of glial cells in vitro.
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PMID:Glial fibrillary acidic protein and intermediate filaments in human glioma cells. 8 66

Glial fibrillary acidic protein (GFA) expression was induced in rat C6 glioma in chemically defined medium by the addition of N6, O2'-dibutyryl cyclic AMP (dbcAMP). Induction was dependent on the increase in intracellular cyclic AMP (cAMP), which was linearly correlated with added dbcAMP. Contrary to GFA mRNA synthesis, which can be obtained by cAMP-dependent and -independent pathways, translation of mRNA into GFA was observed only above a cellular cAMP concentration of approximately 0.2 fmol/cell. dbcAMP stimulation did not affect the vimentin concentration, which remained at a low level, but changed the cellular morphology from a bipolar to a stellate shape. A similar morphological change was observed after stimulation of C6 with lipopolysaccharide (LPS). However, LPS did not significantly increase the intracellular concentration of cAMP and the LPS-induced mRNA was not translated into GFA. Our results indicate that GFA synthesis is regulated at the mRNA level and at the translational level and that a cAMP-dependent mechanism determines the ultimate synthesis of GFA by a yet unknown mechanism.
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PMID:Synthesis of glial fibrillary acidic protein in rat C6 glioma in chemically defined medium: cyclic AMP-dependent transcriptional and translational regulation. 131 74

The sarcomatous component of gliosarcomas is thought by many to originate from the vascular proliferation seen in glioblastoma multiforme and has, therefore, been assumed to be endothelial. Immunohistochemical staining of four gliosarcomas has led us to an alternate theory. Pathologically all four tumors were composed of at least two cell types; the first had a stellate, glial appearance and the second was either spindled or polygonal in shape. Polygonal cells were associated with glomeruloid vascular structures in some areas. Both components of each neoplasm were cytologically malignant. Glial fibrillary acidic protein and S-100 antibodies stained most of the glial-appearing cells and some of the spindled cells, but not the polygonal cells. Muscle specific alpha-actin and smooth muscle specific alpha-actin antibodies stained only the malignant spindled and polygonal cells and normal vascular smooth muscle. Ulex europaeus agglutinin I and anti-factor VIII/related antigen antibody stained only cells lining vascular lumina. The staining results suggest that the malignant mesenchymal component of these tumors is of smooth muscle origin. Having demonstrated elsewhere that glomeruloid vascular structures of glioblastoma multiforme contain smooth muscle cells, we propose here that gliosarcomas can represent one end of the spectrum of glioma-induced vascular smooth muscle proliferation.
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PMID:Smooth muscle can comprise the sarcomatous component of gliosarcomas. 138 14

Glial fibrillary acidic protein (GFAP) is a 49 kDa component of 8 nanometers glial intermediate filaments. It is a definitive marker of both neoplastic and non-neoplastic glial cells. Malignant gliomas are heterogeneous in their structure and their expression of GFAP. Subjective visual impression of glioma cell cultures in early passage after explantation suggested two types of heterogeneity among the cells: 1) Indirect anti-GFAP immunofluorescence (IF) signal intensity appeared to vary among cells. 2). Sizes and shapes of cells appeared to vary. While many cultures lost GFAP+ cells by passage 2, some retained sufficient cells for study. Computerized microdensitometry and image analysis precisely assessed signal intensity, size and shape of glial cells from these latter cultures in passage 2 of cell culture. A Zeiss ICM 405 epi-illuminated fluorescent microscope with photographic interface to a Bio-Quant computerized microdensitometer measured IF signal intensity for GFAP. Normalized to the most intense reactivity, the mean intensity of GFAP expression of 26 glioma cells was 66.2%. The range of 5.2% to 100% around this mean reflected a high degree of heterogeneity of expression of GFAP by these cells. The effects of quenching of the fluorescent signal by the excitation beam were minimized in the following manner: a) Rhodamine anti-GFAP was substituted for more labile fluoresceine. b) A fluorescent filter and lens combination was selected to provide a high signal to quench ratio. c) The signal acquisition time was minimized and fixed to one standard interval. The image analysis system employed the described optics and computer.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Computerized image analysis of distinct cell marker parameters of glial fibrillary acidic protein: intensity of immunofluorescence and topography in human glioma cultures. 157 46

Glial fibrillary acidic protein (GFAP) is a constituent of intermediate filaments of glial cells of the astrocyte lineage. We cloned a human GFAP complementary DNA, deduced the amino acid sequence, and established the chromosomal location (17q21) of the GFAP gene by Southern blot hybridization of somatic cell hybrids and by in situ hybridization. The authenticity of the complementary DNA was proven by expressing it in glioma cells lacking endogenous GFAP; after microinjection of the complementary DNA, such cells became positive for staining with GFAP antibodies. The levels of fibronectin (FN) and GFAP mRNA of ten human glioblastoma cell lines, determined by Northern blot hybridization of RNA, were related to other phenotypic characteristics [cell morphology and expression of the genes encoding platelet-derived growth factor (PDGF) receptors]. A high expression of GFAP mRNA was found only in cells lacking fibronectin mRNA and protein. Glioma cells with a fibroblastic phenotype (bipolar, FN+/GFAP-) were found to express both types of PDGF receptors (alpha and beta). Relatively high levels of PDGF alpha-receptor mRNA, in the absence of beta-receptor expression, were found in cell lines that express GFAP and lack detectable levels of fibronectin mRNA. The findings are compatible with the idea that the genes encoding PDGF receptors in glioma cells are regulated in concert with other genes, the expression of which may reflect the developmental program of normal glia cell lineages.
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PMID:Human glial fibrillary acidic protein: complementary DNA cloning, chromosome localization, and messenger RNA expression in human glioma cell lines of various phenotypes. 184 65

The immunocytochemical staining patterns of cultured glioma cells were investigated. Fifty nine individual cases were stained at different in vitro ages for glial fibrillary acidic protein, fibronectin, galactocerebroside, HNK-1/Leu 7, A2B5, vimentin, factor VIII and A4. Histologically, the cases were composed of eight low-grade astrocytomas, 11 high-grade astrocytomas, four low-grade oligodendrogliomas, seven high-grade oligodendrogliomas and 29 glioblastomas. The 45 cases were analysed within the first 3 weeks of culture, many of them as primary cultures. In 11 cases stainings were performed repeatedly at intervals of up to 6 months. Glial fibrillary acidic protein staining was positive in most of the early cultures of astrocytomas (low and high grade) and glioblastomas; expression in more than 50% of the cells was found in 1 of 5 low-grade astrocytomas, 5 of 11 high-grade astrocytomas and 14 of 29 glioblastomas. Two of the high-grade astrocytomas were stained once more after 6 weeks in culture and were found to be only 1% positive for glial fibrillary acidic protein but strongly positive for fibronectin. The same was true for five of the glioblastoma cases. Two of these cases remained glial fibrillary acid protein positive and developed into stable permanent cell lines. Only one case started with 1% of glial fibrillary acidic protein positive cells and later developed into a 99% glial fibrillary acidic protein positive cell line. Neither HNK-1/Leu 7 expression nor A2B5 staining appeared to have a relationship to the glial fibrillary acidic protein staining. It was observed that glial fibrillary acidic protein and HNK-1/Leu 7 were both 100% in some cases but that later one of the two antigens disappeared but not the other. The amount of glial fibrillary acidic protein staining does not allow the prediction of A2B5 staining. The study shows that initiation of primary cultures on an extracellular matrix yields more glial fibrillary acidic protein positive cells in primary cultures than have been found in other studies. It is concluded that only a rigid standardization of culture conditions will ensure the validity of comparisons of in vitro data obtained in primary cultures.
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PMID:Antigenic staining patterns of human glioma cultures: primary cultures, long-term cultures and cell lines. 224 42

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

A cultured glioma cell line, SR-B10.A, which was derived from a brain tumor induced in an adult female B10.A mouse by Rous sarcoma virus (RSV), has been established. The morphological appearance of the tumor produced by s.c. inoculating SR-B10.A cells was analogous to an astrocytoma of human glioma. Glial fibrillary acidic protein as well as S-100 protein was positive in these SR-B10.A tumor cells. A population doubling time of the cultured cells was 18.5 hours. Chromosomal analysis revealed a defect in one of the sex chromosomes. Integration of RSV genome was proven to be positive in SR-B10.A cells. It was possible to generate cytotoxic effector cells in the syngeneic B10.A mouse against SR-B10.A. The tumor-bearing syngeneic hosts harbored a suppressor activity in the splenocytes. Although recombinant human tumor necrosis factor (rH-TNF) had no growth inhibitory effect on the SR-B10.A cells in vitro, the s.c. implanted and growing tumor regressed when rH-TNF was administered intratumorally several times. In addition, this anti-tumor effect was completely abrogated when the host mice were treated with wholebody x-ray irradiation prior to the tumor cells inoculation. In contrast, neither rH-TNF (i.v.) nor cyclophosphamide (i.p.) induced the regression of SR-B10.A, indicating that efficacy of the locally administered rH-TNF is dependent on the host immune mechanism. These results suggest that SR-B10.A is a potentially useful tumor model in evaluating efficacy of immunomodulators.
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PMID:Potential usefulness of a cultured glioma cell line induced by Rous sarcoma virus in B10.A mouse as an immunotherapy model. 255 17

A permanent human brain malignant glioma cell line, GBM8401/TSGH,NDMC, has been successfully established from a 31-year-old Chinese female with brain glioblastoma multiforme (GBM) in monolayer culture and has been subcultured for more than 100 passages during 24 months in vitro. The tumor cell doubling time in vitro was approximately 38 hr. The tumorigenicity in athymic nude mice was observed; the tumor volume doubling time was approximately 4 days. Glial fibrillary acidic protein (GFAP) and 10-nm-diameter intermediate filaments were identified by immunohistochemical peroxidase-antiperoxidase (PAP), immunofluorescence assay, and transmission electron microscopic methods. The scanning electron microscope revealed numerous surface microvilli and various-sized blebs. Karyotypic analysis showed this malignant glioma cell line to be of human origin, near-diploid with a modal chromosome number of 48,XX.
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PMID:Establishment and characterization of a malignant glioma cell line, GBM8401/TSGH,NDMC. 283 37

Diffuse astrocytomas of the cerebrum, cerebellum, brain stem, and spinal cord are classified into three groups according to the degree of tumor anaplasia. These groups are the astrocytoma, anaplastic astrocytoma, and glioblastoma multiforme. Juvenile pilocytic astrocytomas have a better prognosis and are clinically and biologically distinct from the diffuse, fibrillary astrocytomas. The prognosis of astrocytomas depends not only on histologic characteristics, but also age of the patient, location of the tumor, and extent of surgical resection. The pattern of invasion into surrounding brain distinguishes gliomas from metastatic carcinomas and sarcomas. Topographic correlations have shown that malignant gliomas may invade the brain for distances of up to several centimeters from the enhancing rim seen on CT scan. However, the junction between glioblastoma and adjacent brain may also be fairly abrupt, with a peripheral margin of less than 1 mm. Recurrent glioblastomas are more widely invasive and often extend into areas that appear normal on CT scan. The optimal site for tumor biopsy corresponds to areas of contrast enhancement. Primitive neuroepithelial tumors are malignant neoplasms with a poor prognosis. They tend to recur locally and metastasize throughout the neuraxis via the CSF. It remains controversial whether these tumors should be classified as a single entity with the potential for differentiation along different cell lines, or whether the categories of neuroblastoma, spongioblastoma, ependymoblastoma, pineoblastoma, and medulloblastoma should be retained as specific entities. The medulloblastoma is the most common of these neoplasms, its clinicopathologic features are well characterized, and the current 5-year survivals of 50 to 60 per cent are better than for other "primitive" neoplasms. Glial fibrillary acidic protein is a specific marker for immature, reactive, and neoplastic astrocytes and ependymal cells. Although the absence of GFAP in a neoplasm does not exclude an astrocytic origin, the presence of GFAP indicates astrocytic or ependymal differentiation. This has important diagnostic applications. The expression of GFAP is used to distinguish astrocytic neoplasms from epithelial or mesenchymal tumors that may on occasion mimic a glioma. The detection of GFAP is also useful in the investigation of tumor histogenesis and differentiation both in vivo and in vitro. Although meningiomas exhibit a wide variety of histologic patterns, most tumors exhibit similar biologic and clinical behavior regardless of the histologic subtype.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Pathologic analysis of primary brain tumors. 300 88


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