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)

The aim of this work was to determine if the total (Na+ + K+)-ATPase of the plasma membrane of a cell population could be assayed without cell homogenization and partial purification of the enzyme. Several types of intact cells that were placed in an assay medium containing MgATP, Na+, and K+ hydrolyzed little or none of the added ATP. When the cells were pretreated with the ionophore alamethicin and then placed in the assay medium, they exhibited an ouabain-sensitive (Na+ + K+)-ATPase activity that increased and reached a limiting value with increasing alamethicin concentration. Since alamethicin did not increase the activity of the purified membrane-bound (Na+ + K+)-ATPase, its effects on the intact cells are probably due to the formation of large channels within the plasma membrane that allow the free access of the components of the assay medium to the intracellular domains of (Na+ + K+)-ATPase. Utilizing whole cells treated with alamethicin, total (Na+ + K+)-ATPase activity was determined in clonal pheochromocytoma cells (PC12), neuroblastoma x glioma hybrid cells (NG108-15), and myocytes isolated from adult and neonatal rat hearts. With the use of this whole-cell assay, the ouabain sensitivities of the enzymes in adult and neonatal rat heart myocytes were determined and found to be the same as those that have been determined with the use of partially purified enzymes.
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PMID:Determination of total (Na+ + K+)-ATPase activity of isolated or cultured cells. 256 Mar 48

Many cancers have been cured by chemotherapeutic agents. However, other cancers are intrinsically drug resistant, and some acquire resistance following chemotherapy. Cloning of the cDNA for the human MDR1 gene (also known as PGY1), which encodes the multidrug efflux protein P-glycoprotein, has made it possible to measure levels of MDR1 RNA in human cancers. We report the levels of MDR1 RNA in greater than 400 human cancers. MDR1 RNA levels were usually elevated in untreated, intrinsically drug-resistant tumors, including those derived from the colon, kidney, adrenal gland, liver, and pancreas, as well as in carcinoid tumors, chronic myelogenous leukemia in blast crisis, and cell lines of non-small cell carcinoma of the lung (NSCLC) with neuroendocrine properties. MDR1 RNA levels were occasionally elevated in other untreated cancers, including neuroblastoma, acute lymphocytic leukemia (ALL) in adults, acute nonlymphocytic leukemia (ANLL) in adults, and indolent non-Hodgkin's lymphoma. MDR1 RNA levels were also increased in some cancers at relapse after chemotherapy, including ALL, ANLL, breast cancer, neuroblastoma, pheochromocytoma, and nodular, poorly differentiated lymphoma. Many types of drug-sensitive and drug-resistant tumors, including NSCLC and melanoma, contained undetectable or low levels of MDR1 RNA. The consistent association of MDR1 expression with several intrinsically resistant cancers and the increased expression of the MDR1 gene in certain cancers with acquired drug resistance indicate that the MDR1 gene contributes to multidrug resistance in many human cancers. Thus, evaluation of MDR1 gene expression may prove to be a valuable tool in the identification of individuals whose cancers are resistant to specific agents. The information may be useful in designing or altering chemotherapeutic protocols in these patients.
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PMID:Expression of a multidrug resistance gene in human cancers. 256 56

Partial monosomy of the short arm of chromosome 1 is the most consistent cytogenetic abnormality found in human neuroblastomas, but its overall frequency and significance are unclear. Using a panel of chromosome-1-specific DNA probes that identify restriction fragment length polymorphisms, we demonstrate that 13 of 47 human neuroblastomas (28%) have somatic loss of heterozygosity (LOH) at one or more loci on the distal short arm of chromosome 1. the chromosomal region that shows LOH most consistently is between 1p36.1 and 1p36.3; loss of a gene or genes in this region may be critical for the development or progression of neuroblastomas. The region of LOH in human neuroblastoma may resemble that described for pheochromocytoma, medullary thyroid carcinoma, and melanoma, which are also tumors of neural-crest origin. Although LOH for distal chromosome 1p can occur in early stages of neuroblastoma, the loss usually occurs in tumors of advanced clinical stages. LOH for the short arm of chromosome 1 correlates significantly with N-myc amplification, suggesting that these two genetic events are related. Indeed, these two lesions appear to characterize a genetically distinct subset of particularly aggressive neuroblastomas.
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PMID:Loss of heterozygosity for the short arm of chromosome 1 in human neuroblastomas: correlation with N-myc amplification. 256 96

By restriction fragment length polymorphism (RFLP) analysis, it was found that loss of heterozygosity (LOH) at three different chromosomal loci, 3p, 13q, and 17p, occurs simultaneously in nearly 100% of small-cell lung carcinomas (SCLC). This was observed even in stage I tumors and an untreated tumor, and it occurred prior to NMYC amplification. The common region of LOH on chromosome 3p was 3p14-24.1, and this region was also frequently lost in carcinoma of the uterine cervix (100% at D3S2 on 3p14-21) as well as renal cell carcinoma (56% at ERBA beta on 3p22-24.1), suggesting the presence of tumor suppressor gene(s) for these cancers in this region. On chromosome 13, LOH was observed commonly in the region between 13q12 and 13q22, including the RB locus on 13q14, and normal RB protein was not detected in any of 9 SCLC cell lines by immunoprecipitation analysis. The common region of LOH on chromosome 17 was 17p13 and is the same as that in colon carcinoma and osteogenic sarcoma. Since LOH is supposed to unmask the recessive mutation of tumor suppressor gene in the remaining allele, these results may imply that at least six genetic alterations are necessary to convert a normal cell into a fully malignant cancer cell in SCLC. RFLP analysis was performed on several other types of human cancers, including carcinoma of the uterine cervix, neuroblastoma, hepatocellular carcinoma, pheochromocytoma, and stomach cancer to determine the chromosomal loci of putative tumor suppressor genes in each tumor. Chromosomal loci showing frequent LOH were different among these tumors.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Multiple genetic alterations in small-cell lung carcinoma. 257 37

Intracellular pH (pHi) was measured at the tips of extending neurites and in the corresponding cell bodies of single cultured mouse neuroblastoma (N2A) and rat pheochromocytoma cells (PC12) using the fluorescent dye 2,3-di-cyanohydroquinone (DCH). It was observed that pHi at the tip of an extending neurite was consistently 0.2-0.3 pH units higher than pHi in the cell body. Experiments performed on whole cells to establish the types of cellular mechanism which could be responsible for such regional differences demonstrate the presence of Na+-H+ exchange and Cl- HCO3- exchange in these cells. Since regional variations in Ca2i+ have been reported between neurites and the cell body, experiments were performed to examine the possible interactions between pHi and Ca2i+. Intracellular calcium was measured using the fluorescent Ca2+-sensitive dye Indo-1. An increase in pHi, on application of NH4Cl, resulted in a transient elevation of Ca12i+. On subsequent acidification, on removal of NH4Cl, there was a further transient increase in Ca2i+. These changes in Ca2i+ were also present in solutions with low calcium suggesting that Ca2i+ is mobilized from within the cell. The results are discussed in terms of possible mechanisms whereby the extension and retraction of cell processes could be influenced by Ca2i+ and modulated by pHi.
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PMID:Interactions between intracellular pH and calcium in single mouse neuroblastoma (N2A) and rat pheochromocytoma cells (PC12). 259 28

From September 1984 to March 1989, 57 children received intraoperative radiotherapy as part of a multidisciplinary tumor treatment. Their age ranged from 2 to 18 years. Tumor types: osteosarcoma, 21; Ewing's sarcoma, 19; soft tissue sarcomas, 6; neuroblastoma, 5; Wilm's tumor, 3; Hodgkin, 1; glioma, 1, and malignant pheochromocytoma, 1. In 44 patients the disease was localized while 13 had distant metastases. Intraoperative radiotherapy was used in 48 previously untreated patients as part of a radical treatment program and in 9 cases as an effort to rescue local failures (5 in previously irradiated areas). The intraoperative radiation field included the surgically exposed tumor or tumor bed, and the single doses ranged from 10 to 20 Gy, with 6-20 MeV electrons. With a median follow up time of 25 months (4 to 51 + months) 44 out of 57 patients are alive without local recurrence and 13 have died from tumor (6 with local progression). Intraoperative radiotherapy seems to be a feasible treatment which might promote local control in pediatric tumors.
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PMID:[Intraoperative radiotherapy in the multidisciplinary treatment of malignant tumors in children. Preliminary results]. 263 10

Endocrine hypertension secondary to disorders of the adrenal glands is uncommon, but by no means rare. The importance of correct biochemical diagnosis and subsequent localization of the responsible lesion(s) lie in the fact that many of these syndromes occur in younger patients, may exhibit familial patterns of inheritance and are frequently amenable to surgical cure. The radiopharmaceuticals (131)1-6 beta-iodomethyl-19-norcholesterol (NP-59), a marker of adrenocortical cholesterol uptake, and (131)1- and (123)1-metaiodobenzylguanidine (MIBG), a norepinephrine (NE) analog and marker of energy-dependent NE storage vesicle accumulation, can be shown to accurately localize adrenal cortex and sympathoadrenal dysfunction, respectively. In Cushing's syndrome (CS) not only does the pattern of NP-59 uptake depict the adrenal dysfunction and its pathophysiologic basis, but the level of NP-59 accumulation reflects the degree of adrenocortical hyperfunction. Adrenocorticotrophin-independent CS is uniformly and accurately localized, especially in bilateral cortical nodular hyperplasia where even high resolution computed tomography (CT) may fail to depict the often subtle, asymmetric anatomic abnormalities. Dexamethasone suppression NP-59 adrenal scintigraphy has been shown to be highly sensitive and specific, and exceeds the efficacy of CT in the differentiation of adenoma and bilateral hyperplasia in primary aldosteronism. MIBG is useful as a sympathoadrenal imaging agent whose clinical utility has been demonstrated in the localization of pheochromocytoma, especially as a modality to screen the body for multiple and extraadrenal, recurrent, or metastatic lesions. Moreover, the extent of metastatic involvement from neuroblastoma can also be accurately depicted using MIBG. In this review we will examine the role of adrenal scintigraphy in the characterization of hypersecretory disorders of the adrenal cortex, medulla, and related conditions that produce hypertension as part of their symptom(s) complex. This approach, which is complementary to other anatomical modalities of imaging, can be used to advantage in the localization of functioning cortical and medulla adrenal diseases and other neoplasms of adrenergic origin.
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PMID:Scintigraphic studies in adrenal hypertension. 265 11

We looked for cells that reacted with monoclonal antibodies against rat insulin-like growth factor II (IGF-II). We found them in human fetal kidneys in the 14th week of gestation and in adult adrenal medullas but not in human liver, pancreas, pituitary gland, or thymus. Every pheochromocytoma in a group of 20 had IGF-II-like immunoreactive cells, as did three out of four ganglioneuroblastomas (one of which was heterotransplantable in athymic nude mice) and one carotid body tumor. Using the electron microscope we localized the immunoreactivity in pheochromocytoma cells to their neurosecretory granules of the non-catecholamine type. We failed to find any IGF-II-reactive cells among the pancreatic islet cell tumors, neuroblastomas, medullary carcinomas of the thyroid, retinoblastomas, and Wilms' tumor we studied. One line of human neuroblastoma cells did show some immunoreactivity after treatment with dbcAMP. Additionally, the rat pheochromocytoma cell line PC12 and its subline PC12h occasionally produced a few immunostained cells. These results strongly indicate that human IGF-II is primarily produced in paraganglionic tissues and tumors.
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PMID:IGF-II-like immunoreactivity in human tissues, neuroendocrine tumors, and PC12 cells. 268 Mar 64

Radio-iodinated m-iodobenzylguanidine (MIBG), an analogue of the neurotransmitter norepinephrine (NE), is increasingly used in the diagnosis and treatment of neural crest tumors. Active uptake and subsequent retention of MIBG and NE was studied in human neuroblastoma SK-N-SH cells. Neuron-specific uptake of [125I]MIBG and [3H]NE saturated at extracellular concentration of 10(-6) M and exceeded by 20-30-fold that by passive diffusion alone. A minimum of 50% of accumulated MIBG remained permanently stored but the SK-N-SH cells were incapable of retaining recaptured [3H]NE. [125I]MIBG was displaced from intracellular binding sites by unlabeled MIBG with 10-fold higher potency than by unlabeled NE. MIBG stored in SK-N-SH cells was insensitive to depletion by the inhibitor of granular uptake reserpine (RSP) and was not precipitated in a granular fraction by differential centrifugation. Only few electron-dense granules were found in these cells by electron microscopy. In contrast, MIBG storage in PC-12 pheochromocytoma cells which contained many storage granules, was sensitive to RSP and part of accumulated drug was recovered in a granular fraction. Accordingly, storage of MIBG in the SK-N-SH neuroblastoma cells is predominantly extravesicular and thus essentially different from that of biogenic amines in normal adrenomedullary tissue or in pheochromocytoma tumors, while sharing with these tissues a common mechanism of active uptake.
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PMID:Active uptake and extravesicular storage of m-iodobenzylguanidine in human neuroblastoma SK-N-SH cells. 272 Jun 53

From September 1984 to July 1987, 33 children received intraoperative radiotherapy as part of a multidisciplinary tumor treatment. Their age ranged from 2 to 17 years. Tumors types: Ewing's sarcoma (n = 11), osteosarcoma (n = 8), soft tissue sarcomas (n = 5), Wilms' tumor (n = 3), neuroblastoma (n = 3), malignant pheochromocytoma (n = 1), Hodgkin's disease (n = 1), and optic nerve glioma (n = 1). In 25 patients the disease was localized while 8 had distant metastases. Intraoperative radiotherapy was used in 26 previously untreated patients as part of a radical treatment program and in 7 cases as an effort to rescue local failures (5 in previously irradiated areas). The intraoperative radiation field included the surgically exposed tumor or tumor bed, and the single doses ranged from 10 to 20 Gy, with 6-20 MeV electrons. Patients with osteosarcoma and recurrent tumor in a previously irradiated area did not receive postoperative external beam radiotherapy. With a median follow-up time of 10 months (1 to 31 + months) 24 out of 33 patients are alive without local recurrence and 9 have died from tumor (5 with local disease progression). Intraoperative radiotherapy seems to be a feasible treatment which might promote local control in pediatric tumors.
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PMID:Intraoperative radiotherapy in the multidisciplinary treatment of pediatric tumors. A preliminary report on initial results. 273 16


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