Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0017636 (glioblastoma)
 18,345 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Anomalies of the epidermal growth factor receptor (EGFR) gene, including amplification, rearrangement, and overexpression, have been reported in malignant human gliomas in vivo. In vitro glioma cell lines coexpress EGFR and at least one of its ligands, transforming growth factor alpha, suggesting the existence of an autocrine growth stimulatory loop. We have studied the tumor tissue from 62 human glioma patients and examined the structure and quantity of the EGFR gene and its transcripts, as well as the quantity of the receptor protein. In addition we have examined the genes and transcripts coding for the pre-pro forms of epidermal growth factor and transforming growth factor alpha, the two endogenous EGFR ligands. EGFR gene amplification was detected in 16 of the 32 malignancy grade IV gliomas (glioblastoma) studied (50%), but only in 1 of 30 gliomas of lesser malignancy grade (I-III). All tumors with an amplified gene overexpressed EGFR mRNA. More than one-half (62.5%) of the glioblastomas with amplified EGFR genes also showed coamplification of rearranged EGFR genes and concomitant expression of aberrant mRNA species. Overexpression, without gene amplification, was observed in some of the low grade gliomas, and aberrant EGFR transcripts were also seen in some cases without gene amplification or detected gene rearrangements. mRNA expression for one or both of the pre-pro forms of the ligands was detected in every tumor studied. Thus, several mechanisms for the activation of the EGFR-mediated growth stimulating pathway are possible in human gliomas in vivo: expression of a structurally altered receptor that may have escaped normal control mechanisms; and/or auto-, juxta-, or paracrine stimulating mechanisms involving coexpression of receptor and ligands, with or without overexpression of the receptor.
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PMID:Genes for epidermal growth factor receptor, transforming growth factor alpha, and epidermal growth factor and their expression in human gliomas in vivo. 200 34

Peripheral blood mononuclear cells (PBM) from normal donors and patients with recurrent glioma were activated initially for 48-72 h with phytohemagglutinin-P (PHA) and recombinant human interleukin-2 (IL-2), and then proliferated in vitro for up to 5 months with IL-2. These cells are termed mitogen-stimulated lymphokine-activated T killer (T-LAK) cells. We measured patterns of T-LAK cell growth, in vitro cytolytic activity on a panel of continuous and primary tumor cells, and the phenotypes of the cells in these cultures. Lymphocyte viability declined dramatically over the first 3-5 days; and then the remaining cells in these cultures began to divide and maintained a constant 30-36 h doubling time for long periods in vitro. Phenotyping revealed that cells in the initial few days of culture were heterogeneous, but became almost totally CD3 T cells after 7-10 days in culture. The T-LAK cells from individual normal donors and cancer patients demonstrated a non-genetically restricted cytolytic ability against a panel of both continuous cell lines and primary autologous and allogeneic glioblastoma cells in vitro. This technique provides a method of generating large numbers of autologous cytolytic T cells with non-restricted anti-tumor activity that can be derived from peripheral blood mononuclear cells.
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PMID:Generation of stimulated, lymphokine activated T killer (T-LAK) cells from the peripheral blood of normal donors and adult patients with recurrent glioblastoma. 201 99

A large-animal model was developed to facilitate the noninvasive investigation of the effect on the human glioma-derived D-54 MG (glioblastoma multiforme) continuous cell line of a variety of therapeutic regimens. Twenty random-bred male cats were inoculated intracerebrally with 1 x 10(7) D-54 MG tumor cells after being initiated on one of three preparatory regimens of cyclosporin A p.o. Reproducible success of D-54 MG xenotransplantation (100%, 6 of 6 cats) was achieved only after pretreatment with 120 mg cyclosporin A p.o. (24-30 mg/kg) daily for greater than or equal to 10 days prior to tumor implantation. High-performance liquid chromatography-derived whole blood cyclosporin A 12-h trough levels of greater than or equal to 640 ng/ml were seen in successful implants. Lesions ranging from 2 to 20 mm in diameter were seen in cats sacrificed 27-44 days after implantation with no growth seen in control animals. Histopathological examination revealed the tumors to be well-circumscribed anaplastic intracerebral tumors with some invasion into surrounding host parenchyma. Perivascular lymphocytic cuffing was observed, but intratumoral lymphocytic infiltration was minimal. Gadolinium-EDTA-enhanced nuclear magnetic resonance imaging provided accurate tumor localization in T1-weighted images (TE 26 ms; TR 600 ms). Biochemical tests of kidney, liver, and hematological function were within normal limits, although 10% (2 of 20) of the animals developed gingival hyperplasia, and 5% (1 of 20) developed intussusception. The reproducible growth of the D-54 MG human glioblastoma cell line in a large-animal model eliminates many of the limitations associated with the standard nude mouse/rat model, thereby providing a novel test bed for a variety of imaging modalities as well as for drug immunoconjugate localization and toxicity studies.
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PMID:Development of a large-animal human brain tumor xenograft model in immunosuppressed cats. 201 4

Among new therapeutic modalities for both primary and secondary brain tumors, selective manipulation of metabolic pathways seems attractive. In human malignant gliomas and cell lines from a glioblastoma multiform, lonidamine has been shown to interfere with aerobic glycolysis with a decrease of lactate production by the inhibition of a mitochondrially-bound hexokinase; this selective reduction of the energetic capabilities of glioma cells would be a limiting factor for processes requiring energy, such as cell growth and recovery from potentially lethal damage after radiotherapy or chemotherapy. The activity of lonidamine in malignant gliomas after surgery in association with conventional radiotherapy is being investigated, while previous studies have suggested a limited, but clear therapeutic activity of the drug in recurrent malignant gliomas. In brain metastases lonidamine has not been effective as a radiation enhancer, but has been shown to potentiate systemic chemotherapy. Most common side effects were myalgias, testicular pain and ototoxicity with no serious organ toxicity or myelosuppression.
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PMID:Lonidamine in malignant brain tumors. 203 Nov 97

Antigen expression in a human glioblastoma was investigated by immunochemical methods in the primary tumor, the first and second recurrence, a permanent cell line derived from the first recurrence and in its xenotransplantation tumors. In the primary tumor, GFAP, vimentin, S100, Leu-7 and glioma-associated antigens (GAA) as defined by the monoclonal antibodies (mAbs) MUC 2-39, MUC 8-22 and MUC 2-63 were markedly expressed. In the recurrences, gradual loss of GFAP and Leu-7 could be observed, whereas S100, vimentin and GAA gave similar results to those in the primary tumor. In contrast, fibronectin and collagen IV, which were restricted to the vessel walls in the primary tumor, were represented in sarcomatous areas of the recurrences. In some of these areas, co-expression of glial cell markers was observed. In short-term cell cultures, expression of glia- and glioma-associated antigens as well as fibronectin and collagen IV was comparable to that of the recurrent tumor tissue. In long-term passages, immunoreactivity of GFAP, Leu-7 and S100 decreased, whereas GAA, vimentin and fibronectin increased. Collagen IV positive cells were not visible beyond passage 15. Transplantation tumors were only partly positive for glial cell markers, but revealed strong immunoreactivity for GAA, fibronectin and collagen IV. With these observations we confirm that the phenotypic variability of glioma cells makes it difficult to identify the origin of cells in human glioblastomas from their antigenicity.
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PMID:Antigen variation in a human glioblastoma: from the primary tumor to the second recurrence, permanent cell line and xenotransplantation tumors. 206 11

Clinical phase I/II studies have been performed at the Swiss Institute for Nuclear Research (SIN) since February 1982. Fifty-two out of 249 patients accepted for pion treatment by the end of 1986 were treated for malignant glioma with high dose pion irradiation. A substantial influence of their radioresistance was expected from increased radiation quality due to the contribution of high LET particles from pion capture, and by the possibility of target volume shaping and dose distribution related to the dynamic spot-scan conformation technique. The patients' treatment followed a dose escalation program with total doses from 2720-3420 cGy, fraction sizes from 170 to 205 cGy (90% isodose, minimum target dose), and treatment times from 4 to 5 weeks. 12/52 patients received an accelerated treatment with 3280 cGy in 14-22 days. 49/52 patients are eligible: 3 with astrocytoma of clinical aggressive behaviour, 14 with anaplastic astrocytoma (median age 42 years), and 32 patients with glioblastoma (median age 52 years). 8/49 patients had total/subtotal tumour resection, 19 patients a stereotactic biopsy. The patients were divided into three groups according to total dose, and a fourth group which received the accelerated treatment. There was no statistically significant difference in the median survival rate between the four groups, which was 13 months for the non-glioblastoma patients and 9 months for the glioblastoma patients. No radiation necrosis and no demyelination was found in 17 patients (6 recraniotomies, 11 autopsies). In 10/17 patients, clearly identifiable tumour cells were not demonstrated. NMR findings showed the tumour-surrounding oedema mostly stimulated by tumour necrosis and tumour progression. From these findings, further dose escalation programs, together with a shaping of the target volume close to the tumour, are not contraindicated.
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PMID:Anaplastic astrocytoma and glioblastoma: pion irradiation with the dynamic conformation technique at the Swiss Institute for Nuclear Research (SIN). 210 74

Peripheral-type benzodiazepine receptors (PBR), unlike central-type benzodiazepine receptors, are found in low concentrations in normal brain. Because PBR have been described in neoplastic cells of neuroglial origin, they have been suggested for imaging human glial tumors and for directing cytotoxic therapy at these tumors. Little information exists, however, on the presence or pharmacology of PBR in human glial tumors. Using radioligand binding techniques, we have demonstrated that 6 out of 6 glioblastoma (GBM) specimens had high concentrations of PBR [( 3H]PK 11195 binding sites) which were significantly greater than in 5 normal human frontal cortex samples. The pharmacologic specificity of these sites differed significantly from that of PBR in human and rat kidney specimens. Saturation binding experiments revealed a small number of high affinity sites and a substantial number of sites of intermediate affinity. Under in vitro binding conditions the more numerous lower affinity site is the major contributor to specific binding measurements. The ligand recognition site of the PBR in human GBM tissue was photoaffinity labeled using [3H]PK 14105, a nitrophenyl analogue of PK 11195. Subsequent SDS-polyacrylamide gel electrophoresis revealed specific incorporation of label into a 17,300 molecular weight component. There was no specific incorporation into normal human frontal cortex, but a component of very similar molecular weight was demonstrated in human kidney. We conclude that human glioblastomas consistently express PBR sites that are present in greater density than in normal human brain. Imaging of human glial tumors with analogues of PK 11195 thus appears feasible. Further molecular characterization of the photoaffinity-labeled PBR may also provide new information on the biology of these tumors.
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PMID:Peripheral-type benzodiazepine receptors in human glioblastomas: pharmacologic characterization and photoaffinity labeling of ligand recognition site. 216 48

Six patients with glial tumours showing xanthomatous change are reported here. Four patients in the series showed features of anaplastic (malignant) glioma or glioblastoma multiforme. In these patients, the astrocytic origin of the xanthomatous cells was confirmed by electron microscopy and immunohistochemistry using glial fibrillary acidic protein (GFAP). Of these, in one patient (no. 4) xanthomatous change was seen in an anaplastic (malignant) mixed glioma with significant ependymal component. Only one patient (no. 5) could be considered histologically as pleomorphic xanthoastrocytoma, but no clinical follow up was available. The value of immunohistochemical staining for GFAP in distinguishing gliomas with xanthomatous change from true xanthofibromas and xanthosarcomas was demonstrated in one patient (no. 6) in whom the glioblastomatous areas were GFAP positive but the xanthomatous areas were negative. This was therefore considered as a rare condition of glioblastoma with xanthosarcoma.
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PMID:Xanthomatous change in tumours of glial origin. 217 36

We found a direct correlation between increasing ras p21 protein immunopositivity and severity of human glioma using computer-assisted, digital-image processing to quantify the amount of p21 immunoreactive to the monoclonal antibody RAP-5. We determined that there was a significant difference in reactivity between glioblastoma multiformes and more-differentiated astrocytomas (experiment-wise error less than 0.05). This result confirmed the conclusions made on the same tumors using standard light microscopy and visual examination. Immunohistochemistry quantized by automated image analysis may be a useful adjunct to current histopathological strategies since it decreases assay subjectivity and variation.
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PMID:Application of automated image analysis to demonstrate the correlation between ras p21 expression and severity of gliomas. 219 8

The neu gene in rat neuro/glioblastoma was found to be activated by a single point mutation in the DNA sequence encoding the transmembrane region of the neu-encoded p185 protein. The human homologue of the rat neu gene, termed c-erbB-2 or HER-2, can also be activated in vitro by a similar mutation in the corresponding region. Although the human neu gene was shown to be amplified/overexpressed in a large portion of human breast and ovarian cancer, no reports indicate that the human neu gene is activated by a point mutation in human tumor. To study the possible point mutation of neu gene in human tumors, we characterized the genomic structure in the transmembrane region of human neu gene, which in turn allowed us to determine DNA sequence in this region directly following DNA amplification by polymerase chain reaction. We analyzed 7 tumor cell lines (2 breast cancer, 1 neuroblastoma, 1 rhabdomyosarcoma, and 3 glioma) and 11 tumor tissue samples (8 breast and 3 ovarian cancers). No mutation was found in the transmembrane region of human neu gene. Our results suggest that unlike the rat neuro/glioblastoma, the single point mutation in the transmembrane region of the human neu gene is a rare event in human tumors. In this study, we developed a technique for direct DNA sequencing of the transmembrane region of the human neu gene. This technique makes it possible to screen a large number of tumor samples.
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PMID:Direct sequencing analysis of transmembrane region of human Neu gene by polymerase chain reaction. 220 83


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