Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027819 (neuroblastoma)
 27,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We report three cases of neurilemoma occurring in the superficial soft tissue of the palm, posterior neck, and flank that closely resembled neuroblastoma by virtue of a predominance of small, round hyperchromatic schwann cells with scant cytoplasm which, in one case formed perivascular rosettes and, in the others, giant rosettes with central collagen cores. Although the diagnosis of neuroblastic tumor was seriously entertained in all cases, the diagnosis of a schwannoma was substantiated by the finding of focal areas of conventional schwannoma and by the typical immunophenotypic profile. All tumors strongly and diffusely expressed S-100 protein but lacked neurofilament protein, protein gene product (PGP), and synaptophysin. Ultrastructurally the cells contained slender cytoplasmic processes invested with basal lamina, but no dense core granules. All were excised conservatively, and none has recurred during the 2, 12, and 27 month follow-up periods.
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PMID:Neuroblastoma-like neurilemoma. 811 94

The histological localization of the ret proto-oncogene (proto-ret) product was examined in neural crest-derived and neuronal tissues together with their neoplastic counterparts by immunohistochemistry using a polyclonal antibody. Schwann cells, neurons, sympathetic ganglia, and cells of the adrenal medulla were positive for the proto-ret product, whereas melanocytes were negative. Positive results were obtained from neural crest-derived tumours such as schwannoma (69 per cent, 11/16), neurofibroma (59 per cent, 13/22), neuroblastoma (80 per cent, 4/5), phaeochromocytoma (100 per cent, 3/3) and medullary thyroid carcinoma (100 per cent, 3/3). The antibody reacted with all of the 22 astrocytomas examined. With negative proto-ret expression in melanocytic tumours, proto-ret expression was considered to correlate with the differentiation of some lineages of neural crest-derived cells.
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PMID:Expression of the ret proto-oncogene product in human normal and neoplastic tissues of neural crest origin. 819 28

We developed an IgG1 mouse monoclonal antibody (ONS-M21) directed against a cell surface antigen of medulloblastomas and gliomas in immunisation of mice with the ONS-76 medulloblastoma cell line. The antibody specifically reacted with medulloblastomas, supratentorial primitive neuroectodermal tumours (SPNETs) and gliomas, but not with other neuroectodermally derived tumours (neuroblastoma and melanoma) or with other kinds of tumours (meningioma, neurinoma, leukaemia, and small cell lung cancer). No reactivity was identified with normal body tissues, including peripheral blood cells. Characterisation of the ONS-M21 antigen showed that it was a trypsin-sensitive glycoprotein with a molecular weight of 80 kDa on SDS-PAGE. The pattern of reactivity and the biochemical properties of this antigen were different from those of other markers of medulloblastoma. These results indicate that ONS-M21 detects a new tumour-associated cell surface antigen specifically expressed by medulloblastomas, SPNETs, and gliomas. This is the first report that medulloblastomas may share common cell surface antigens with gliomas, although most studies have concluded that medulloblastoma has a predominantly neuronal phenotype. The lack of reactivity with normal tissue implies that ONS-M21 has potential applications as both a diagnostic tool and a therapeutic agent.
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PMID:Characterisation of a new mouse monoclonal antibody (ONS-M21) reactive with both medulloblastomas and gliomas. 821 97

The frequency of different malignant cutaneous tumors (MCTs), primary and metastatic, in children is not known. We reviewed all MCTs, primary and metastatic, seen during a 20-year period in a large general pediatric hospital. Fifty-three MCTs, 36 primary and 17 metastatic, were diagnosed in 36,207 pediatric dermatology patients. The incidence was 1.4 per 1000 patients. The relative frequency of occurrence of the different tumors was as follows: rhabdomyosarcoma, 25%; lymphomas, 19%; basal cell carcinoma, 13%; leukemia, 13%; neuroblastoma, 10%; malignant melanoma, 6%; squamous cell carcinoma, 6%; unclassified sarcomas, 4%; epithelioid schwannoma, 2%; ependymoma, 2%. The mean follow-up was 3 years; 48% died, 27% were lost to follow-up, and 25% are under control. We conclude that primary and metastatic MCTs in children are rare. Their types differ from MCTs in an older age population. MCTs in children are associated with a high mortality rate, often related to late recognition.
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PMID:Malignant cutaneous tumors in children. Twenty years of experience at a large pediatric hospital. 828 84

We are studying the biological activity and regulation of mammalian Ras protein in tumours and in physiological signalling. We have shown that GAP (the GTPase-activating protein) is a potent negative regulator of normal Ras in cells. Reduction or loss of the NF1 gene product neurofibromin, in association with genetic abnormalities of the NF1 locus, has been identified in schwannoma cell lines from patients with neurofibromatosis and in melanoma and neuroblastoma lines from patients without neurofibromatosis. Although loss of neurofibromin in the schwannoma lines was associated with a high proportion of normal Ras protein in the active GTP-bound state, Ras-GTP appeared to be appropriately regulated in the melanoma and neuroblastoma lines, which contain normal levels of GAP. Therefore the GTPase-activating activity of neurofibromin is not essential for negative regulation of Ras in some cell types and the putative tumour suppressor function of neurofibromin in such cell types is independent of its GTPase-activating activity. Mitogen activation of Ras in fibroblasts is mediated primarily by exchange factors, which probably interact with a region on the Ras protein distinct from the region required for interaction with GAP. Multiple full-length cDNAs have identified a mouse gene whose products are related to yeast CDC25 guanine nucleotide exchange factor.
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PMID:Cell transformation by ras and regulation of its protein product. 829 27

T1 and T2 were determined simultaneously in vivo at 4.7 T in implanted rat brain tumors. Three different tumor cell lines were implanted in the right caudate nucleus: the F98 glioma, the E367 neuroblastoma, and the RN6 schwannoma. Their T1 and T2 values (mean +/- standard deviation [msec]), respectively, were 1,312 +/- 107 and 89 +/- 3 (glioma), 1,284 +/- 86 and 87 +/- 7 (neuroblastoma), and 1,338 +/- 85 and 86 +/- 9 (schwannoma). The T1 values (msec) of normal brain and muscle were 1,090 +/- 59 and 1,139 +/- 77, respectively, and the T2 values (msec) were 76 +/- 3 and 36 +/- 2, respectively. After injection of the contrast agent manganese (III) tetraphenylporphine sulfonate (TPPS) the T1 of all three tumors decreased by 30% and the T2 by 10%, whereas no such change in relaxivity was noted in normal brain. As a result, strong contrast enhancement of the three tumor types was seen on T1-weighted images. The tumor was clearly delineated and correlated with findings at histologic examination. This tumor enhancement was followed up for 4 days with quantitative relaxation time measurements, and the strong, selective reduction in T1 for all three tumor types after Mn-TPPS injection was preserved over the entire observation period.
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PMID:In vivo relaxometry of three brain tumors in the rat: effect of Mn-TPPS, a tumor-selective contrast agent. 842 1

Solid mediastinal masses in infancy and childhood occur most frequently in the posterior mediastinum. From 1972 to 1989, 63 patients presented with a posterior mediastinal mass. The median age at diagnosis was 6 years (range, 1 day to 26 years). Thirty patients were female. Forty-five percent of the patients presented with respiratory symptoms or chest pain; 13% had neurologic symptoms, one half of which were related to spinal cord compression; and 5% had a palpable mass. In 32% of patients the mass was an incidental finding. The tumors were of neurogenic origin in 89% of patients, of which neuroblastoma was the most common. Of all patients with posterior mediastinal masses, 60% had malignant tumors. Median follow-up for 62 of 63 evaluable patients was 45 months (range, 1 to 289 months). One patient was lost to follow-up. Of the 62 patients followed, 84% are alive and free of disease. All but 4 of the 32 patients with neuroblastoma are alive and free of disease with a median follow-up of 73 months (range, 7 to 289 months). Patients with neuroblastoma who were diagnosed in the first year of life had a significantly better survival pattern than those presenting after the first year. There were seven deaths in the series: four from neuroblastoma, two from primitive neuroectodermal tumor, and one from malignant schwannoma. Preoperative diagnostic evaluation of a posterior mediastinal mass should include posteroanterior and lateral chest roentgenograms, and either CT or MRI of the chest and abdomen to assess the extent of the mass.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Posterior mediastinal masses. 843 74

The NF1 gene, which is altered in patients with type 1 neurofibromatosis, encodes neurofibromin, a protein whose GTPase-activating function can negatively regulate GTP-Ras by accelerating its conversion to inactive GDP-Ras. In schwannoma cell lines from patients with neurofibromatosis, loss of neurofibromin was previously shown to be associated with impaired regulation of GTP-Ras. Our analysis of other neural crest-derived tumor cell lines has shown that some melanoma and neuroblastoma cell lines established from tumors occurring in patients without neurofibromatosis contain reduced or undetectable levels of neurofibromin, with concomitant genetic abnormalities of the NF1 locus. In contrast to the schwannoma cell lines, GTP-Ras was appropriately regulated in the melanoma and neuroblastoma lines that were deficient in neurofibromin, even when c-H-ras was overexpressed in the lines. These results demonstrate that some neural crest tumors not associated with neurofibromatosis have acquired somatically inactivated NF1 genes and suggest a tumor-suppressor function for neurofibromin that is independent of Ras GTPase activation.
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PMID:Inactivation of the NF1 gene in human melanoma and neuroblastoma cell lines without impaired regulation of GTP.Ras. 851 98

The potential of quantitative parameter images of the relaxation times T1 and T2, the proton density rho and the apparent diffusion coefficient (ADC) to characterize three different experimental rat brain tumors (F98 glioma, RN6 Schwannoma, and E376 neuroblastoma) was studied. All parameter values, as determined in histologically confirmed regions of interest (ROI), were higher in edema than in tumor, which in turn were elevated with respect to normal brain. ROI values of ADC and T2 delivered statistically significant (P < 0.01) differentiation between tumor and edema. Multidimensional parameter combinations improved differentiation between different tissues. However, the three tumor types could not be differentiated. All parameter maps allowed the identification of the whole tumor-edema area. On T2 images, edema could be identified best, whereas the tumor itself was hardly visualized. In many cases, tumor presentation using T1 maps corresponded best with histology, nevertheless suffering from a poor tumor-edema differentiation.
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PMID:High resolution quantitative relaxation and diffusion MRI of three different experimental brain tumors in rat. 859 10

The adrenal scintiscan with 123I-metaiodobenzylguanidine (MIBG), a reliable morphofunctional technique to evaluate catecholamine turnover in adrenal tumors, can be a useful method to investigate adrenal incidentalomas with arterial hypertension. A male patient, 44 yr old with diabetes, unstable arterial hypertension, and sudden paroxysms of tachycardia is described. The presence of a disomogeneous right juxta-adrenal neoplasm with calcifications was evidenced with ultrasound tomography and confirmed by computerized tomography (CT) scan. Adrenal 123I-MIBG scintiscan revealed a unilateral uptake at level of the right juxta-adrenal region, sized similarly to the neoplasm previously evidence by CT scan. Histological findings of the surgically removed neoplasm were consistent with an ancient schwannoma. Apart from pheochromocytomas, the MIBG uptake is commonly reported in neuroblastomas. In neuroblastoma, a bidirectional process of transdifferentiation has been previously reported in vitro between two coexistent cells: cells with specific uptake system for norepinephrine, with 123I-MIBG uptake capability, and cells oriented toward schwann/melanocytic line. The evidence of in vivo MIBG uptake in our schwannoma may be caused by the same possible phenotypic interconversion of above mentioned cell types. In conclusion, the presence of adrenal tumors with MIBG uptake capability, apart from pheochromocytomas, neuroblastomas, ganglioneuroblastomas, and ganglioneuromas, must be considered in the diagnosis of adrenal tumors.
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PMID:Usefulness of 123I-metaiodobenzylguanidine (MIBG) scintiscan in the diagnosis of juxta-adrenal schwannoma. 863 13


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