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)

Molecular characterization of neuroendocrine (Merkel cell) carcinoma of the skin. Review of the literature and report of three cases. Although neuroendocrine carcinoma of the skin (NECS) is comparatively a rare clinical-histological entity, numerous morphological and ultrastructural studies have been carried out since the tumor was identificated by Toker (1972). Recently immunocytochemistry has allowed a better molecular characterization (immunophenotype) of this tumor and a more exact diagnosis. The main problem for the pathologist is the differential diagnosis between NECS and skin neoplasms--both primitive and metastatic--which require a more aggressive treatment. Often the classical morphological criteria do not distinguish NECS from non-Hodgkin's lymphoma, amelanotic melanomas, cutaneous metastases of lung small cell carcinoma or of neuroblastoma. The co-expression of cytokeratins and neurofilaments constantly found in NECS, is surely the best differential criterion from non-neuroendocrine carcinomas. Furthermore, the typical paranuclear location of both the intermediate filaments in NECS is a distinctive peculiarity as opposed to lung microcytoma, where cytokeratins and neurofilaments, when present, show widespread perinuclear positivity. Chromogranin A is found only in a small percentage of tumor cells, whilst synthesis of calcitonin, somatostatin, gastrin, ACTH, is very rare. Finally, the lack of common leukocyte antigen (CLA), S-100 protein and vimentin in NECS rules out the diagnoses of lymphoma, melanoma and sarcoma respectively.
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PMID:[Molecular characterization of cutaneous neuroendocrine (Merkel cell) carcinoma. Review of the literature and presentation of a caseload]. 209 Oct 10

Fragments of 5'-flanking and noncoding exon I sequences of the human gastrin gene were analyzed in transient expression assays after transfection of a variety of cell lines with the pSVCAT vector system. In the presence of the simian virus 40 (SV40) enhancer, the gastrin gene fragment from nucleotides -250 to +57, relative to the cap site, was as efficient a promoter as the SV40 early promoter itself. In the absence of the SV40 enhancer, gastrin gene 5'-flanking sequences had no promoter activity except in the murine neuroblastoma cell line N18TG2. In this cell line, the fragment from -1300 to +57 stimulated transcription as actively as the SV40 early promoter with its enhancer. This cell-specific gastrin gene promoter activity was in accordance with the finding that gastrin is synthesized in certain neuronal cells. Promoter activity declined with decreasing distance from the 5' end to the cap site and disappeared after removal of the gastrin gene TATA box. In vector constructions containing short vector-linker sequences homologous to a functionally important region of the SV40 enhancer, the gastrin gene fragment from -17 to +57 showed considerable promoter activity, exclusively in N18TG2. It is concluded that the truncated gastrin gene promoter plus the first exon contains a cell-specific element that may act in collaboration with upstream elements to facilitate the accumulation of transcripts.
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PMID:Cell-specific expression of the human gastrin gene: evidence for a control element located downstream of the TATA box. 283 Apr 90

The usefulness of radio-metaiodobenzylguanidine (MIBG), a specific radiopharmaceutical agent for scintigraphic imaging and treatment of phaeochromocytoma and neuroblastoma, has been extended to the location of carcinoid tumors. Scintigraphic evaluation with I-123 MIBG in a patient with a histologically proven endocrine tumor (apudoma) of unknown origin with liver and bone metastases is reported. Elevated plasma hormone levels of gastrin, pancreatic polypeptide, and serotonin were found. Tumoral content of these hormones was immunocytochemically confirmed on liver biopsy. I-123 MIBG uptake could be seen in those areas of the liver with deficient lesions in the Tc-99m colloid image with a maximal uptake in a large mass at the level of the left liver lobe. No abnormal uptake could be observed at any other level, which was in contrast with autopsy findings of generalized metastatic disease.
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PMID:Iodine-123 MIBG imaging in a generalized pancreatic polypeptide-gastrin-serotonin secreting tumor. 339 Sep 81

Various tumor cells contain chromatographically distinct isoacceptor tRNA species. To decide whether the tumor-specific species represent an expression of a separate tRNA gene or only an undermodified form of normal tRNAPhe, nucleotide sequences of tRNAPhe isolated from neuroblastoma and normal mouse liver were determined by postlabeling techniques. The results showed identical sequences except for the changes of post-transcriptional modifications in the anticodon loop. Normal mouse liver tRNAPhe contained Cm32, Gm34, and the hypermodified YOH next to the 3' end of the anticodon. On the contrary, tRNAPhe from neuroblastoma contained C32, G34, and, instead of YOH base m1G. A small proportion of tRNAPhe species contained an undermodified YOH base. For the examination of the conditions leading to the undermodified tRNAPhe, Vero cells derived from the kidney of African green monkey in culture were used. In these cells, deprivation of methionine or lysine resulted in changes in tRNAPhe modification similar to those in tumor cells. Ehrlich ascites tumor cells were examined to determine whether the presence of altered tRNAPhe species in various tumors is also the result of starvation of some nutritional factors. Results obtained with these cells showed that tRNAPhe species lacking the Y base disappeared in tumor-bearing mice after intraperitoneal injection with a mixture of amino acids and vitamins. Thus it is concluded that tumor-specific tRNAPhe species are the products of aberrant post-transcriptional modification, not the transcripts of different, normally repressed genes.
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PMID:Alterations in post-transcriptional modification of the Y base in phenylalanine tRNA from tumor cells. 640 57

Nucleotide sequences of normal mouse liver tRNAPhe and tumor-specific tRNAPhes isolated from Ehrlich ascites tumor and neuroblastoma cells were examined by post-labeling techniques. The results showed that their sequences are identical, except for changes in post-transcriptional modifications that are located in the anticodon region. Normal mouse liver tRNAPhe contained Cm32, Gm34 and YOH37. On the other hand, tumor-specific tRNAPhes were found in one of two possible configurations: 1) Cm32, Gm34 and Y*OH37 (under-modified YOH) or 2) C32, G34 and m1G37. The ratio of the two forms of tRNAPhes differed in different tumor cells; Ehrlich ascites tumor tRNAPhe had mainly Y*OH-containing tRNAPhe whereas neuroblastoma tRNAPhe has predominantly m1G-containing tRNAPhe. It was concluded that tumor-specific tRNAPhes are products of different extents of modification, rather than of new tRNA transcription.
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PMID:Changes of post-transcriptional modification of wye base in tumor-specific tRNAPhe. 692 49

Gastrin releasing peptide is mitogenic for mouse Swiss 3T3 fibroblasts and certain human small cell lung carcinoma (SCLC) cells but not for mouse Balb/c 3T3 fibroblasts. To identify new molecules associated with the gastrin releasing peptide-responsive phenotype, clones isolated from a differential cDNA library between Swiss and Balb/c 3T3 fibroblasts were used to screen for their expression in human SCLC cell lines. Using this approach, we have isolated and characterized human and mouse cDNA clones encoding a novel protein. This protein is a putative transmembrane protein belonging to the epidermal growth factor-like superfamily. In vitro transcription and translation studies detect a 42-kDa protein, in agreement with the size predicted from the translated cDNA sequence. This protein (termed Delta-like or dlk) is highly homologous to invertebrate homeotic proteins, including Delta, and Notch, the products of neurogenic loci involved in normal neural differentiation in Drosophila. dlk is expressed in tumors with neuroendocrine features, such as neuroblastoma, pheochromocytoma, and a subset of SCLC cell lines. However, its expression in normal tissues is restricted to the adrenal gland and placenta. These data suggest that dlk may be involved in neuroendocrine differentiation and, because of its cellular location and restricted expression in normal tissues, it may be a potential therapeutic target in neuroendocrine tumors, particularly SCLC.
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PMID:dlk, a putative mammalian homeotic gene differentially expressed in small cell lung carcinoma and neuroendocrine tumor cell line. 809 43

A novel series of potent and selective non-peptide neuropeptide Y (NPY) Y1 receptor antagonists, having benzazepine nuclei, have been designed, synthesized, and evaluated for activity. Chemical modification of the R(1) and R(3) substituents in structure 1 (Chart 1) yields several compounds that show high affinity for the Y1 receptor (K(i) values of less than 10 nM). SAR studies revealed that introduction of an isopropylurea group at R(1) and a 3-(benzo-condensed-urea) group, 3-(fluorophenylurea) group, or a 3-(N-(4-hydroxyphenyl)guanidine) group at R(3) in structure 1 afforded potent and subtype-selective NPY Y1 receptor antagonists. 3-(3-(Benzothiazol-6-yl)ureido)-1-N-(3-(N'-(3-isopropylureido++ +))benzyl )-2,3,4,5-tetrahydro-1H-1-benzazepin-2-one (21), which was one of the most potent derivatives, competitively inhibited specific [(125)I]peptide YY (PYY) binding to Y1 receptors in human neuroblastoma SK-N-MC cells (K(i) = 5.1 nM). 21 not only inhibited the Y1 receptor-mediated increase in cytosolic free Ca(2+) concentration in SK-N-MC cells but also antagonized the Y1 receptor-mediated inhibitory effect of peptide YY on gastrin-induced histamine release in rat enterochromaffin-like cells. 21 showed no significant affinity in 17 receptor binding assays including Y2, Y4, and Y5 receptors.
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PMID:1,3-Disubstituted benzazepines as novel, potent, selective neuropeptide Y Y1 receptor antagonists. 1041 82

PURPOSE:Gastrin-releasing peptide (GRP) is a 27-amino acid neuropeptide that has been identified in the cytoplasm of many neuroendocrine tumors. Gastrin releasing peptide has been labeled as an autocrine growth factor in small cell lung carcinomas. Recent work has also shown this to be true in the growth of neuroblastoma cells in vitro. The purpose of this study was to demonstrate GRP and its receptor (GRP-R) in resected human neuroblastomas and to correlate the presence or absence with other known predictors of poor prognosis.To demonstrate the presence of GRP and GRP-R mRNA, total RNA was extracted from human neuroblastoma cells. A reverse transcription-polymerase chain reaction (RT-PCR) was then performed using specific primers. The products of the RT-PCR were then confirmed to be GRP and GRP-R cDNA by Southern blot analysis. The RT-PCR products were then sequenced, and these sequences were compared with the know sequences of GRP and GRP-R DNA.N = 19. GRP and GRP-R mRNA were present in all neuroblastoma specimens. Although no correlation with other known predictors of poor prognosis existed, transcripts of four different sizes (400, 450, 500, and 950 bp) were seen in the GRP-R transcripts. The sequences of the 950 bp-sized transcript reverse transcription PCR products were identical to the known GRP-R.We conclude that gastrin releasing peptide and gastrin releasing peptide receptor mRNA are present in all human neuroblastomas. Although qualitatively it appears to lack prognostic significance, its ubiquitous nature in the tumor suggests it may be a useful target on which to base future treatment modalities.
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PMID:Gastrin-releasing peptide: a potential growth factor expressed in human neuroblastoma tumors(1). 1122 44

Several neuropeptides are secreted in high amounts in pediatric tumors such as neuroblastoma and have been used as markers of residual or recurrent disease. Plasma levels of neuropeptides might be expected to change during development, but have not been determined in normal children. We have obtained fresh plasma from cord blood of six full-term infants and from peripheral blood in 41 healthy children, ages 1 month to 21 years. Levels of six neuropeptides, vasoactive intestinal peptide (VIP), somatostatin, gastrin releasing peptide (GRP), substance P, pancreastatin and neuropeptide Y (NPY) were measured by radioimmunoassay along with insulin-like growth factor-1 (IGF-1) whose plasma levels are known to vary during development. A child with neuroblastoma was treated with the somatostatin analogue, octreotide, and the effect on plasma neuropeptides quantified. Octreotide doses of 2-3 microg/kg daily resulted in a 40-60% decrease in plasma levels of IGF-1, pancreastatin and GRP. These results are the first publication of plasma neuropeptide levels in normal children.
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PMID:Age-dependent levels of plasma neuropeptides in normal children. 1240 32