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)

The concurrent daily intragastric administration of ethylurea at two dose levels (50 mg/kg and 100 mg/kg bodyweight) together with one dose level of sodium nitrite (50 mg/kg bodyweight) by a stomach tube to pregnant BD IX rats from day 15 to day 22 of gestation resulted in the induction of neurogenic tumors in all offspring. Since both ENU-precursors alone do not produce neurogenic tumors, these results are evidence of ENU formation from its precursors under the influence of gastric juice. Differences in the survival time and the incidence of tumors at both dose levels were not significant. The amount of ethylnitrosourea synthesized in the animals was very close at both dose levels, and was dependent on the amount of sodium nitrite applied. The experimental results are consistent with the conclusion, that the rat fetuses had been exposed to a total amount of about 60 mg/kg ethylnitrosourea. Neurogenic tumors dominated with 98% incidence over the non-neurogenic. The incidence of neurogenic tumors per rat was high (6.0 for Group I and 6.7 for Group II). Neurogenic tumors were equally distributed among the central and peripheral nervous systems. The neurogenic tumors induced with the precursors of ethylnitrosourea were morphologically similar in all aspects to those induced with the carcinogen itself and could be classified as oligodendroglioma, astrocytoma, mixed glioma, anaplastic glioma, glioependymoma, ependymoma, and neurinoma. Three unusual tumors were found: one early anaplastic "septum ependymoma" in the dorsal column of the spinal cord, and two special mixed tumors of the cranial nerves, i.e. a neurinoma with portions of an oligodendroglioma and a neurinoma with parts of an invasive ependymoma.
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PMID:Transplacental induction of neurogenic tumors in BD IX rats by intragastric administration of ethylnitrosourea precursors. 12 44

The brains of 396 old albino rats of the breed Wistar-AF/Han-EMD were examined for spontaneous tumors of the CNS and the following tumors were diagnosed: 1 oligodendroglioma, 1 astrocytoma, 1 mixed glioma, 1 pleomorphic glioma, and 19 meningiomas. Thus the CNS tumor rate was 5.8%. In addition 6 micromeningiomas were found. Knowledge of the spontaneous tumor rate including the tumor incidence in the CNS of the animal strains used for these examinations is a necessary condition for the evaluation of the results of cancerogenicity tests. CNS tumors deserve particular attention because during recent years it was found that certain chemical compounds like for instance N-methyl-N-nitrosourea induce organ-specific tumors in the brain of rats. It is recommended, therefore, to always include the central nervous system in the autopsy and histologic examination of animals from cancerogenicity trials. For cerebral autopsy transversal sections through the different cerebral regions and histologic examination of transversal section surfaces of all tumors and suspected tumor areas are suggested.
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PMID:The incidence of spontaneous tumors of the central nervous system of Wistar rats. 17 67

Brain tumors were induced in 3-month-old rabbits of either sex by repeated intravenous injections of N-methyl-N-nitrosourea. Twelve brain tumors (6 pleomorphic gliomas, 5 grade 2--3 astrocytomas, 1 grade 2--3 oligodendroglioma) were established in culture and, with the exception of 2 neoplasms, were propagated in vitro as permanent cell lines. The glial nature of all cell lines was ascertained at several passage levels by testing the cells for the production of S-100 and GFA. It could be shown that most cells of all lines fluoresced positively for the S-100 protein, albeit differences in intensity of fluorescence were clearly noted between cells of the same culture and between different cultures. In general, astrocytoma cell lines had the strongest fluorescence. Pleomorphic glioma cells but especially astrocytoma cells reacted positively also for the GFA protein. Surprisingly enough, isolated cells of the oligodendroglioma line also showed evidence of GFA production. Exposure of cultures of rabbit glioma cells to db-cAMP for 8--10 hr resulted in inhibition of cell proliferation and stimulation of process formation. Furthermore, positive fluorescence for the S-100 and GFA proteins was more intense in cells treated with db-cAMP than in untreated cells. The latter observation may indicate that production and/or accumulation of glial proteins also was enhanced during the stationary phase of cell cultures.
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PMID:Morphological, immunocytochemical and biological characteristics of experimental rabbit brain tumors in tissue culture. 22 1

The clinical and pathological report presents a seven-week old girl suffering from signs of raised ICP. A ventriculo-atrial shunt was inserted and replaced by a ventriculo-abdominal shunt due to occlusion at 15 months of age. At 16 months, craniotomy and resection of an oligodendroglioma was performed and the shunt was preserved. The child died at 18 months due to extensive local recurrence. Autopsy revealed massive peritoneal metastases of the tumor. This is the eleventh published case of canalicular metastases of glioma.
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PMID:[Extraneural metastasis of an oligodendroglioma in ventriculo-peritoneal shunt]. 36 90

Tumors of the nervous system were induced in Sprague-Dawley and Long-Evans rats by weekly administrations of 6 mg/kg N-methyl-N-nitrosourea in the drinking water. Three of these tumors, a grade 2 mixed glioma, a grade 2 to 3 astrocytoma and a grade 1 to 2 oligodendroglioma, were established in culture and propagated in vitro. The mixed glioma strain (75SD-G-376) and the astrocytoma line (75SD-G-420) were repeatedly subcultured, cloned at passage 90 and 120 and designated as 75SD-G-376C and 75SD-G-420C clone, respectively. The growth rate of the oligodendroglioma cell strain (77LE-G-180) was very low and the cells died off after the 5th in vitro passage. The glial nature of all lines was ascertained by demonstrating the presence of the S-100 protein in the culture cells. 2 1/2 years after the establishment in vitro of the 75SD-G-376 and 75SD-G-420 primary cultures, mass cultures as well as clones derived from them are still producing S-100 and thus are clearly comparable to the primary cultures, at least in this respect. From a morphological standpoint based on light microscopy, cells of clonal lines with relatively few and short processes differ, however, from cells of primary cultures and their uncloned lines. Therefore, the cell morphology of these clones can be viewed upon as a form of adaptation to the in vitro conditions. It can be concluded that permanent cell lines with well-defined properties can be grown from experimental brain gliomas successfully established in culture and maintained in vitro.
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PMID:Selected morphological immunocytochemical and growth characteristics of three experimental rat gliomas and of their cells in vitro. 43 44

The composition of the free amino acid pools in various brain tumors and in normal brains obtained at surgery or at autopsy is determined with an automatic amino acid analyzer and the results statistically evaluated. The tumors have lower ratios of GABA in the pools than the normal brain; tumors with higher GABA ratios are found in those which are in close contact with and have an invasive nature to brain tissue. In gliomas, the more malignant a tumor becomes, the more different the composition in that tumor is from that in normal brain tissue. But conversely, the ratio of GABA is highest in glioblastoma. The composition of the pool in oligodendroglioma is not significantly different from that in the normal brain. Metastatic brain tumors show the highest ratios of phenylalanine, tyrosine and methionine in the pool among the tumors and the normal brain. From the viewpoint of the composition of the free amino acid pools, like from that of the histological aspects, brain tumors seem to be classified into four groups: glioma, neurinoma, meningioma and metastatic tumors.
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PMID:Composition of free amino acids in brain tumors. 54 90

We used a new immunocytoadhesion method to test 15 different tumors of the human nervous system to see whether medulloblastomas share tumor-associated surface antigens (TSA) with other tumors. Antisera against medulloblastoma cells were raised in rabbits. One antiserum was adsorbed extensively with tonsil and adenoid cells and with cerebral tissues. Freshly isolated cells from 15 different tumors were first sensitized with the adsorbed antiserum and then rosetted with erythrocytes coated with purified antibody to rabbit immunoglobulin. We found that the antimedulloblastoma antiserum detected TSA on the immunizing medulloblastoma cells and on cells from 2 other medulloblastomas, but apparently not on cells from other tumors (astrocytomas, glioblastomas, neurinoma, meningiomas and craniopharyngioma). In addition, the antiserum probably detected the medulloblastoma TSA on some other tumors (oligodendroglioma, ependymoma and malignant glioma of mixed type).
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PMID:Comparison of tumor-associated surface antigens on cells from medulloblastomas and from other neoplasms of the human nervous system. 56 78

Brain tumors were induced in Sprague-Dawley and Long-Evans rats by administration of N-methyl-N-nitrosourea in the drinking water. Of these tumors, a grade 2 mixed glioma, a grade 2 to 3 astrocytoma and a grade 1 to 2 oligodendroglioma were established in vitro, maintained in culture and designated 75SD-G-376, 75SD-G-420 and 77LE-G-180, respectively. Of these mass cultures, two were successfully cloned and are currently available as 75SD-G-376C and 75SD-G-420C cell lines. Clonal lines produce S-100 protein and grow as tumors when isografted in young rats. Using the cultured cells as target cells , specific antibodies were searched for in the sera of the rats with the primary tumors by means of an indirect fluorescent antibody staining method and a complement-dependent antibody-mediated microcytotoxicity assay. Fluorescent and cytotoxic antibodies were demonstrated in the sera of the mixed glioma- and astrocytoma-bearing animals. However, a variable proportion of cells of the 75SD-G-376 and 75SD-G-420 lines showed no reaction with the corresponding sera. Furthermore, cytotoxic antibodies had a lytic effect on the autologous glioma cells only in the presence of rabbit complement.
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PMID:Tumor specific fluorescent and complement-dependent cytotoxic antibodies in the serum of rats with chemically induced brain gliomas. 67 75

The fine structure of rat gliomas induced transplacentally with a single i.p. dose of 50 mg/kg of Ethylnitrosourea has been studied by using transmission and scanning electron microscope. The subependymal matrix layers of the fetus which was affected by ENU have showed irregular and rough arrangements with expanded extracellular spaces as compared with that of control rats. The cells of subependymal layer seemed to form the microtumor. A so-called "microtumor", which was found in a 8 week old, has been composed of small round cells. The fine structures of these cells have showed the characteristics in primitive oligodendroglioma. The characteristics of the fine structure of astrocytoma cells was identified by both TEM and SEM. The fine structure of subependymal glioma cells was often pleomorphic. These gliomas contained a mixture of primitive oligodendrocytes and ependymal cells together with anaplastic glial cells. With increasing size, the glioma has become more pleomorphic with a mixture of neoplastic oligodendrocytes, astrocytes and ependymal cells, and ependymoma like cells have showed neither cilia nor junctional complex. Abnormal vascular structure in the tumor has been reconfirmed by injection replica scanning electron microscope method. The fine structure of the separated single tumor cell surface was also studied by scanning electron microscope. The differences of the cells surface between that of astrocytoma cell and oligodendroglioma cells were clearly noticed.
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PMID:[Experimental brain tumors produced transplacentally by ethylnitrosourea (IV): ultrastructure studied by using transmission and scanning electron microscope (author's transl)]. 70 10

A case of sarcoma arising in a left temporal oligodendroglioma is described in a 39-year-old male. The postoperative evolution was marked by a paraplegia linked to medullary and subarachnoid metastases. Then a relapse of the cerebral tumor occurred, and the patient died 6 months after the onset of the symptoms. Histologically, the mesenchymal component appeared fibrosarcomatous and angiosarcomatous. Those facts argue in favor of the histogenic hypotheses put forward in exceptional cases previously described, according to which the sarcoma develops from vascular elements of the glioma.
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PMID:Sarcoma arising in oligodendroglioma of the brain: a case with intramedullary and subarachnoid spinal metastases. 72 72


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