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 use of labelled radiopharmaceuticals such as metaiodobenzylguanidine (m-IBG) enables neuroblastomas and other malignant cells from neural crests to be visualized. In vitro study of cellular incorporation into human neuroblastoma lines (SK-N-SH, SK-N-MC, LAN I) showed that only the SK-N-SH line retained iodine-125 m-IBG (125I-m-IBG) significantly. Fifty-five percent of the initial activity was retained after 1 hr incubation at a concentration of 10(-7) M of m-IBG (specific activity: 1,480 MBq/mg). Beyond this value, m-IBG uptake mechanisms were saturated. Study of release kinetics showed a rapid first phase (50% released after 4 hr) and a slower second phase (30% of the value retained at the equilibrium point was present after 48 hr), indicating the existence of a storage compartment. Autoradiography studies confirmed the intracytoplasmic localization of m-IBG and showed that a low percentage (3 to 5%) of SK-N-SH cells strongly retained m-IBG. Cytotoxicity tests showed that SK-N-SH cell growth was significantly reduced during the first days of culture, following 2 hr incubation with 1,500 KBq of 125I-m-IBG, whereas no toxic effect on SK-N-MC cells was found at the same activity. Moreover, the toxic effect observed in the SK-N-SH line was clearly related to the use of 125I-m-IBG since the same activity of 1,500 KBq of non-coupled 125I was without effect. For the latter line, colony-forming capacity was reduced for activities of 150 and 1,500 KBq of 125I-m-IBG, with respectively 32% and 38% lower survival rates. The cytotoxic effect of labelled m-IBG was, however, limited in non-saturating concentrations because the specific activity used was too low. Moreover, the low number of cells reconcentrating m-IBG is indicative of the heterogeneous cellular composition of the SK-N-SH line.
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PMID:In vitro therapeutic targeting of neuroblastomas using 125I-labelled meta-iodobenzylguanidine. 235 89

Three children with Stage III neuroblastoma were treated with [125I]MIBG in a phase I toxicity study. Concepts of the treatment were: in small tumors, the absorbed dose of radiation from MIBG labeled with 131I is reduced but the absorbed dose from [125I]MIBG is less affected; and many recurrences of neuroblastoma arise from small tumors. Two patients exhibited only modest thrombocytopenia and leukopenia, the most sensitive indices of radiation toxicity, after receiving 261 and 407 mCi, and 83 and 104 rad of whole-body radiation. One patient died of progressive neuroblastoma; the other two patients have stable disease over 30 mo after treatment. Per millicurie given, [125I]MIBG imparts about one-fourth the radiation dose of [131I]MIBG to the whole body. Iodine-125-MIBG can be given in doses that impart over 100 rad of whole-body radiation and that exceed 400 mCi before toxicity becomes limiting, even in small children.
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PMID:Iodine-125-MIBG to treat neuroblastoma: preliminary report. 199 43

Ten children with stage III or IV neuroblastoma that had either relapsed or was refractory were treated with [131I]-metaiodobenzylguanidine (MIBG) from 1984 to 1986. The total dose ranged from 4,365 to 21,900 MBq and was given in one to five courses. Two patients achieved a complete remission (CR), two, a partial remission (PR), and three, an arrest of the disease. Pharmacological studies showed that 93% of detectable radioactivity was attributable to MIBG at the beginning of the infusion. However, by the end of the infusion this had decreased to 88%. The terminal half-life of MIBG was 37.0 h, whereas that of non-MIBG-bound iodine was 71.6 h. Therefore, the radioactivity-time product of non-MIBG-bound 131I was much higher than that of MIBG. Dosimetric studies showed a mean level of absorbed radiation for the total body of 160 microGy/MBq, a liver irradiation of 540 microGy/MBq and a mean tumour radiation of 10,500 microGy/MBq.
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PMID:[131I]-metaiodobenzylguanidine in the treatment of metastatic neuroblastoma. Clinical, pharmacological and dosimetric aspects. 259 1

Magnetic resonance imaging (MRI) was compared with iodine-131-labeled monoclonal antibody scanning for ability to detect bone marrow metastases in the spine, pelvis, and femurs of children with disseminated neuroblastoma. The five patients in this study had received high-dose chemotherapy and radiation, either with (N = 2) or without (N = 3) bone marrow transplants. MRI disclosed marrow abnormalities at all sites detected with the radiolabeled antibody, which is highly specific for neuroblastoma. However, several diffuse and multifocal marrow changes apparent on MR scans were not present on scintigrams, indicating that MRI is probably less specific than monoclonal antibody imaging. Both methods were more useful than conventional radiography, computed tomography, and 99mTc-MDP bone scans for identifying sites of marrow involvement by neuroblastoma.
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PMID:Comparison of radiolabeled monoclonal antibody and magnetic resonance imaging in the detection of metastatic neuroblastoma in bone marrow: preliminary results. 260 20

Monoiodinated radioligands of the homologous 36-amino acid peptides, neuropeptide Y (NPY) and peptide YY, were prepared by reverse phase high performance liquid chromatography with isocratic elution. [125I-Tyr1]- and [125I-Tyr36]monoiodoNPY bound equally well to a single class of high affinity binding sites on synaptosomal membranes prepared from porcine hippocampus (Kd = 1.0 X 10(-10) M) whereas iodine substitution in Tyr27, for example, partly interfered with the receptor binding. The receptors on the hippocampal membranes did not distinguish between neuropeptide Y and peptide YY either in their monoiodinated or in their unlabeled forms. Six out of twelve human neuroblastoma cell lines had high affinity binding sites for monoiodinated NPY ranging from 2 to 145 X 10(3) sites per cell. The NPY binding to three of the cell lines, SMS-MSN, SMS-KAN, and CHP-234 was of relatively high affinity (Kd = 1.3 to 6.1 X 10(-10) M), and, as in the hippocampal membranes, the long C-terminal fragment, NPY(13-36)peptide was also a relatively potent ligand for these receptors. Two other neuroblastoma cell lines, MC-IXC and CHP-212, expressed NPY receptors characterized by a lower affinity (Kd = 4.8 and 24.6 X 10(-9) M) and negligible cross-reactivity with the C-terminal fragment. It is concluded that monoiodinated radioligands of the tyrosine-rich neuropeptide Y can be prepared and that receptors for these ligands in two apparently different subtypes are found on a series of human neuroblastoma cell lines.
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PMID:Binding of monoiodinated neuropeptide Y to hippocampal membranes and human neuroblastoma cell lines. 270 30

We have examined the binding of tetanus toxin (TT) to surface receptors of neuroblastoma cells by flow cytometry following chemically induced differentiation. Cells were treated with mitomycin C, bromodeoxyuridine, prostaglandin E1 or cyclic adenosine monophosphate at different doses, alone or in combination for 4 days. Cells extended long neurites within 24 h in the presence of prostaglandin/cyclic AMP or mitomycin/bromodeoxyuridine treatment while single-drug treatment was less efficient in morphological differentiation of these cells. Cells exposed to the drug combinations stopped growing after 3 days while flow-cytometric analysis of DNA levels of each cell stained with propidium iodide indicated that at least 60% of these cells were arrested in phase G0/G1 of the cell cycle. Drug-treated cultures were stained for TT binding by immunofluorescence of cells in suspension and analyzed by flow cytometry. Chemically differentiated N2AB-1 cells were shown to bind significantly more TT than control cultures. Receptors for TT could be saturated by increasing doses of TT and differentiated cells bound twice as much toxin at saturation as did control cells. Immunofluorescence of TT binding to monolayers revealed staining in a stippled fashion along all neurites and cell bodies. These data support the concept that drugs which stimulate differentiation of neuroblastoma cells as determined by morphological and cell-cycle criteria also increase the presence of ganglioside receptors on the cell surface available for toxin binding.
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PMID:Tetanus toxin binding to neuroblastoma cells differentiated by antimitotic agents. 300 77

The antibody 3F8, an IgG3 murine monoclonal antibody (MoAb) against disialoganglioside GD2, could target iodine-131 (131I) to established subcutaneous human neuroblastoma (NB) xenografts in BALB/c nude mice. 131I-radiolabeled MoAb (0.125-1 mCi) was injected iv. Tumor radioactivity over time was calculated from scintigraphy, and radiation dose to individual tumors was calculated. Tumor shrinkage occurred only with 131I-labeled 3F8, but not with nonradioactive 3F8 or radiolabeled irrelevant antibody. While the tumor of the control mice enlarged by tenfold, the treated tumor showed over 95% shrinkage by 12 days. Both the rate of shrinkage and duration of tumor response were dose dependent. Calculated doses of more than 10,000 rad could be achieved. Only those tumors that received more than 4,200 rad were completely ablated without recurrence. Recurrent tumors were not antigen negative or radioresistant. These results confirmed the prediction based on imaging studies that human NB xenografts could be effectively eradicated with the use of 131I-labeled MoAb 3F8 with tolerable toxicities.
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PMID:Complete tumor ablation with iodine 131-radiolabeled disialoganglioside GD2-specific monoclonal antibody against human neuroblastoma xenografted in nude mice. 309

Iodine-131 MIBG scintigraphy may be used to determine the presence or absence of metastases to the appendicular skeleton in malignant pheochromocytoma and neuroblastoma. Normal bones show no uptake of [131I]MIBG and the joints are seen as photon-deficient areas surrounded by background muscle activity. Discrete concentrations of radioactivity in bone are often seen in patients with malignant pheochromocytoma and neuroblastoma. Bone marrow involvement in neuroblastoma may be indicated by diffuse uptake of [131I]MIBG or focal accumulation at the metaphyses. Uncommonly, bone involvement may not be displayed by the [131I]MIBG images. Since conventional bone scanning agents may also fail to detect these tumors, skeletal scintigraphy with both [131I]MIBG and [99mTc]MDP is necessary to reliably stage malignant pheochromocytoma and neuroblastoma.
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PMID:Iodine-131 MIBG scintigraphy of the extremities in metastatic pheochromocytoma and neuroblastoma. 310 2

To evaluate the accuracy of meta-iodobenzylguanidine (MIBG) imaging in comparison with bone X-ray and ultrasound, 15 patients with histologically verified neuroblastoma were investigated using 123- or 131MIBG scintigraphy. 123MIBG and 131MIBG are used as the abbreviations for 123-iodine-labeled-MIBG and 131-iodine-labeled-MIBG, respectively. Either 7.4 MBq 131MIBG (n = 4) or 111-185 MBq 123MIBG (n = 11) was applied, and scans were performed 24 and 48 h PI. Anatomical orientation was provided in selected cases by single-photon emission CT or scintigraphy of other organs. X-ray procedures or ultrasound depicted 27 neuroblastoma manifestations (primary tumors and metastatic deposits); 24 of these (89%) were identified by MIBG scintigraphy. Of 42 primary neuroblastomas and metastatic deposits, 27 (64%) were detected by corresponding bone X-ray or ultrasound. The 15 neuroblastoma lesions depicted solely by MIBG scans were mainly (80%) situated in the skeletal system. Because of the pronounced physiological MIBG uptake by liver tissue, detection of intrahepatic or perihepatic tumor involvement is difficult. MIBG scintigraphy is a safe and noninvasive means of locating a wide range of neuroblastoma lesions. Its main diagnostic advantage in comparison with bone X-ray lies in the detection of bone marrow infiltration.
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PMID:Meta-iodobenzylguanidine scintigraphy in neuroblastoma--a comparison with conventional X-ray and ultrasound. 315 32

A patient in whom metastatic medullary thyroid cancer was diagnosed underwent a scintigraphic examination using [131I]MIBG. Multiple hot lesions and diffuse hepatic uptake were noted corresponding to bone and liver metastases. Iodine-131 MIBG may prove to be useful for scintigraphic localization and for the treatment of medullary thyroid cancer as in pheochromocytoma and neuroblastoma.
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PMID:Metastatic medullary thyroid cancer: localization with iodine-131 metaiodobenzylguanidine. 315 26


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