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)

Medulloblastoma, a common pediatric brain tumor, is a primitive neuroectodermal tumor which often displays neuronal and/or glial characteristics. We have investigated the consequences of treating cell lines derived from a human medulloblastoma with glia maturation factor-beta (GMF-beta), a protein found in mammalian brain. GMF-beta promotes growth arrest and morphological alteration of cultured glioma and neuroblastoma cells. The proliferation of medulloblastoma cells was arrested 24-48 hr after exposure to human recombinant GMF-beta. During the same period, treated cells acquired a morphology similar to that of mature astrocytes. By 72 hr, all treated cells bound an antibody against glial fibrillary acidic protein (GFAP), a distinguishing biochemical feature of mature astrocytes. Immunoreactivity was accompanied by de novo expression of GFAP mRNA. Our observations are the first demonstration of the induction of morphological and biochemical characteristics of mature astrocytes in cultured medulloblastoma-derived cells by an exogenous factor.
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PMID:Expression of glial fibrillary acidic protein in human medulloblastoma cells treated with recombinant glia maturation factor-beta. 129 57

Nestin is a recently described member of the intermediate filament (IF) protein family that is especially abundant in neuroepithelial stem cells of the rat. The studies described here examine this class VI IF protein in the normal human developing central nervous system (CNS), human brain tumor-derived cell lines, and tissue samples of human CNS tumors. Human nestin exhibited biochemical and immunochemical properties similar to those of rat nestin. Further, as in the rat, nestin was detected immunohistochemically in several different types of immature human CNS cells, i.e. germinal matrix cells, neuroepithelial cells lining the central canal, radial glia and vascular cells. Nestin appeared in these cells at the earliest gestational age (i.e., 6 weeks) examined here and then it declined in all but the vascular cells at later embryonic stages. Nestin also was detected by immunocytochemistry in 6 of 7 primitive neuroectodermal tumor cell lines and in both of 2 malignant glioma cell lines examined. In these cell lines, nestin co-localized incompletely with bundles of IFs containing other IF proteins (i.e., vimentin, glial filament, neurofilament). Nestin was ubiquitous in a wide variety of brain tumors, but was most prominent in gliomas. The transient expression of nestin in primitive neuroepithelial cells at early stages of human embryogenesis and its abundance in neuroepithelial tumors suggest a role for nestin IFs in cellular events that precede the exit of embryonic CNS stem cells from the cell cycle and the commitment of the progeny of these stem cells to a specific lineage. The subsequent induction of different members of the IF protein family in phenotypically distinct CNS cells (i.e. neurons, glia) and the elimination of nestin from almost all differentiated CNS cells, imply that different classes of IFs subserve functions that are closely linked to the maturational state, as well as the lineage, of CNS cells.
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PMID:Nestin expression in embryonic human neuroepithelium and in human neuroepithelial tumor cells. 153 85

Of 29 consecutive children treated for malignant primary tumors of the central nervous system (CNS) at this institution, postoperative examination showed radiographic or cytologic evidence of neuraxis dissemination in 10 (34%). Given the historically poor results in disseminated CNS tumors treated with surgery and radiation therapy alone, these ten patients were treated prospectively with an investigational Phase II protocol consisting of preirradiation cisplatin (90 mg/m2 on day 1) and etoposide (150 mg/m2 on days 3 and 4). The diagnoses included medulloblastoma (n = 4), malignant glioma (n = 3), cerebral primitive neuroectodermal tumor (n = 1), pineoblastoma (n = 1), and mixed glioma of the brainstem (n = 1). Postoperative neuraxis scanning with computed tomography, magnetic resonance imaging, or spinal myelography showed measurable intracranial or spinal metastases in all children. The cerebrospinal fluid (CSF) cytologic examination was positive for tumor cells in five. The best responses, based on serial imaging of neuraxis metastases, included two complete responses, four partial responses, and three stable disease states. One patient had progressive disease at the primary site despite stable disease in the spine; progressive neuraxis disease was documented in only one patient during chemotherapy. Clearance of tumor cells from the CSF was documented in three patients. The adverse effects of chemotherapy, consisting of transient myelosuppression and mild ototoxicity, were minimal. Reversible neurologic deterioration occurred in two patients; one patient became acutely quadriplegic after a prolonged convulsive seizure without radiographic evidence of tumor progression.
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PMID:Neuraxis dissemination in pediatric brain tumors. Response to preirradiation chemotherapy. 173 73

It is well known that resistance in tumor cells to alkylating agents and, in particular, chloroethylnitrosoureas (CENUs), which are widely used in the chemotherapy of brain tumors, correlate well with activity of the DNA repair enzyme O6-alkylguanine-DNA alkyltransferase (O6-AT). We measured O6-AT activity in human brain tumors in order to obtain basic knowledge of whether or not CENU chemotherapy can be applied selectively on brain tumors. The subjects included 17 gliomas (seven malignant astrocytomas, two glioblastomas, two medulloblastomas, two oligodendrogliomas, two ependymomas, one fibrillary astrocytoma, one primitive neuroectodermal tumor) and five non-glial tumors (three meningiomas, two neurinomas). The value of O6-AT activity for the gliomas varied widely and indicated 111 +/- 65 fmol of 3H-methyl adducts transferred/mg protein extract/hr (mean +/- S.D., range 0-258, 18 tumors), while the non-glial tumors showed a relatively high value of 270 +/- 43 fmol/mg/hr (range 225-330, 5 tumors). A significant difference in the O6-AT activity was noted between the gliomas and the nonglial tumors at the p-value of 0.001. Six (38%) out of 17 glioma cases showed a value below 100 fmol/mg/hr and four cases (24%) a value below 60 fmol/mg/hr. These results provide a biological basis for applying CENU chemotherapy on glioma patients with a lower value of O6-AT enzyme.
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PMID:O6-alkylguanine-DNA alkyltransferase activity in human brain tumors. 180 9

Clone pTB16 has been isolated by differential screening of a human glioma cDNA library. Northern blot analysis has shown that pTB16 expression is several times (greater than 11-fold) higher in gliomas than in a primitive neuroectodermal tumor. This observation was supported by in situ hybridization and extended to nine other gliomas. Expression was virtually absent in adenocarcinoma cells metastasized to brain. Malignant gliomas showed stronger hybridization than benign gliomas, while blood capillaries did not show hybridization. pTB16 mRNA was also shown to be expressed in established glioma cell lines and at high levels in epileptic foci, indicating that expression of the gene may be limited to certain cell types and that its upregulation is not merely a consequence of cellular proliferation. Nucleotide sequence analysis identified pTB16 as the human counterpart for rat testicular sulfated glycoprotein 2 (SGP-2), whose function in the reproductive system remains unknown. Although SGP-2 transcripts, and hence pTB16, were recently shown to be increased in neurodegenerative diseases such as scrapie in hamsters and Alzheimer disease in humans, our observations with brain tumors and epilepsy are suggestive of a role for pTB16 in neuropathologies in general and support the hypothesis of its involvement in tissue remodeling and cell death.
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PMID:Human gliomas and epileptic foci express high levels of a mRNA related to rat testicular sulfated glycoprotein 2, a purported marker of cell death. 192 17

Neuraxis radiation therapy (RT) for primary intracranial tumors is associated with major late effects if administered to very young children. To control residual tumor and to delay RT, we treated eight young children (median age 6.5 months) with primary central nervous system (CNS) tumors using combination chemotherapy: cisplatin, 20 mg/M2/day plus VP-16, 75 mg/M2/day i.v. for 5 days, given q. 3-6 weeks for 8 cycles. The tumors were medulloblastoma (one), malignant ependymoma (two), primitive neuroectodermal tumor PNET (two), malignant glioma (two), astrocytoma (one). Six had measurable disease; three had positive cerebrospinal fluid (CSF) cytopathology. All patients with measurable tumor had initial objective responses (three) complete response [CR], one partial response [PR], two minor response [MR], including cytopathology (three CR of three) and metastatic deposits (two CR of two). One patient relapsed during chemotherapy. Median time to disease progression was 17.5 months; median survival was 34 months. Three patients, none of whom received RT, have prolonged progression-free intervals of 47-67 months to date. Neurodevelopmental progress continued during and after chemotherapy. Chemotherapy toxicity was mild. Median neutrophil nadir was 312/mm3, platelets 72,000. Fever during neutropenia occurred in six of 61 courses. Moderate high-frequency auditory losses were detected in three patients, and mild renal injury (GFR less than 70 ml/min) was detected in two of seven evaluable children. This pilot study demonstrates the apparent efficacy and mild toxicity of 5 day courses of cisplatin plus VP-16, with delayed RT, in young children with CNS neoplasms. A POG treatment protocol that incorporates cisplatin plus VP-16 is evaluating primary chemotherapy with delayed radiotherapy in larger numbers of pediatric brain tumor patients.
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PMID:Efficacy of postoperative chemotherapy using cisplatin plus etoposide in young children with brain tumors. 199 Feb 53

A cerebral primitive neuroectodermal tumor with astrocytic differentiation and extracranial metastases in a 28-day-old infant is reported. The infant presented with a progressively enlarged head, cutaneous lesions in the neck, and enlarged cervical lymph nodes. A computed tomography brain scan demonstrated a giant thalamic tumor with subarachnoid dissemination and hydrocephalus. Biopsy material from the cervical lesions showed a picture of glioma with anaplastic astrocytes. The patient received a ventriculoperitoneal shunt operation and palliative chemotherapy, but died at 3 months of age. Autopsy was performed. Histological studies, which included immunohistochemical stains of the thalamic tumor, showed small, round, primitive, neoplastic cells with focal astrocytic differentiation.
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PMID:Congenital cerebral primitive neuroectodermal tumor with astrocytic differentiation and extracranial metastases. 216 35

Between October 1985 and March 1988, Children's Cancer Study Group institutions entered 95 patients with recurrent brain tumors into a Phase II trial of carboplatin 560 mg/m2 every 4 weeks. Complete or partial responses were observed for one of 19 evaluable children with brainstem glioma, two of 14 with ependymoma, six of 19 with medulloblastoma or central nervous system primitive neuroectodermal tumor (PNET), and none of 15 with high-grade astrocytoma. Of 33 children with medulloblastoma, ependymoma, or central nervous system PNET, five of 12 with no prior cisplatin exposure had responses, and two of 21 with prior cisplatin exposure had responses (P = 0.03). Thirty-four percent of patients had absolute neutrophil count nadirs less than 500/microliters, and 37% had platelet count nadirs less than 25,000/microliters. Sixteen percent had moderate to severe otoxicity, 10% had nausea and vomiting, and none had nephrotoxicity.
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PMID:Carboplatin in childhood brain tumors. A Children's Cancer Study Group Phase II trial. 224 86

Brain tumors are the second most common childhood malignancy. Between 1975 and 1985, 462 newly diagnosed patients were treated at the Children's Hospital of Philadelphia; 207 (45%) tumors arose in the posterior fossa and 255 (55%) appeared supratentorially. A wide variety of histological subtypes were seen, each requiring tumor-specific treatment approaches. These included primitive neuroectodermal tumor (n = 86, 19%), astrocytoma (n = 135, 30%), brainstem glioma (n = 47, 10%), anaplastic astrocytoma (n = 32, 7%), and ependymoma (n = 30, 6%). Because of advances in diagnostic abilities, surgery, radiotherapy, and chemotherapy, between 60% and 70% of these patients are alive today. Diagnostic tools such as computed tomography and magnetic resonance imaging allow for better perioperative management and follow-up, while the operating microscope, CO2 laser, cavitron ultrasonic aspirator and neurosurgical microinstrumentation allow for more extensive and safer surgery. Disease specific treatment protocols, utilizing radiotherapy and adjuvant chemotherapy, have made survival common in tumors such as medulloblastoma. As survival rates increase, cognitive, endocrinologic and psychologic sequelae become increasingly important. The optimal management of children with brain tumors demands a multidisciplinary approach, best facilitated by a neuro-oncology team composed of multiple subspecialists. This article addresses incidence, classification and histology, clinical presentation, diagnosis, pre-, intra- and postoperative management, long-term effects and the team approach in posterior fossa tumors in childhood. Management of specific tumor types is included as well.
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PMID:Pathology, treatment and management of posterior fossa brain tumors in childhood. 296 18

Twelve neonatal brain tumors, presenting within 60 days of birth, constituted 3.3% of pediatric brain tumors. Three-fourths were supratentorial. Two-thirds were benign. Forty-two percent were choroid plexus papilloma. Twenty-five percent were teratoma. Eight percent each were hypothalamic glioma, gliosarcoma, medulloblastoma, and primitive neuroectodermal tumor. Clinical symptoms were nonspecific. Signs of herniation were absent in all 12 patients. Forty-two percent of these patients died 1 day to 8 months after diagnosis. Ultrasound, CT, and magnetic resonance have all proved useful for displaying these lesions suitably for surgery.
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PMID:Neonatal brain tumors: CT and MR findings. 333 47


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