Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The gamma-subunit of 2-phospho-D-glycerate hydrolyase, E.C. 4.2.1.11 (enolase), neuron-specific enolase (NSE), is present at high concentrations in neurons and neuroendocrine cells and has therefore recently been introduced as a marker for neuroendocrine tumors. By the indirect methods, immunocytochemistry and radioimmunoassay, NSE has been detected also in some nonneuroendocrine tumors, a finding that could reflect technical artifacts or the capacity for NSE expression in nonneuroendocrine tumor cells. This paper reports on the expression of NSE in human neuroendocrine and nonneuroendocrine tumor specimens and in a panel of permanent human cell lines, by using a direct (enzymatic) and an indirect (radioimmunoassay) method for determination of NSE. We detected NSE in all tested tumor specimens and neuroendocrine tumor cell lines and in a majority (21 of 24) of the nonneuroendocrine tumor cell lines. In general, neuroendocrine tumor specimens and derived tumor cell lines contained more NSE than the nonneuroendocrine tumor specimens and cell lines. However, some of the cultured hematopoietic cell lines (T leukemia and Epstein-Barr virus immortalized B lymphoblastoid cell lines) had NSE levels comparable to those found in some neuroblastoma and small-cell lung carcinoma cell lines. We conclude that NSE is not exclusively expressed in neuroendocrine tumor cells.
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PMID:Expression of gamma-subunit of enolase, neuron-specific enolase, in human non-neuroendocrine tumors and derived cell lines. 300 68

Selected neuroendocrine tumors, such as small cell lung cancer (SCLC), and neuroblastoma express markedly diminished class I major histocompatibility complex (MHC) antigens (HLA framework and beta 2-microglobulin, beta 2m). Another neuroendocrine tumor, mid-gut carcinoid, also expresses reduced beta 2m antigen as demonstrated herein. Antigen expression is greatly enhanced on SCLC cell lines by in vitro exposure to interferon (IFN). To determine whether IFN mediates similar effects in vivo, we examined by immunoperoxidase staining beta 2m expression in paraffin-embedded tumor tissue sections obtained from 4 SCLC and 7 mid-gut carcinoid patients before and after receiving partially purified human leukocyte IFN-alpha therapy. Before IFN treatment, 3/4 SCLC tumors and 5/7 mid-gut carcinoids did not express beta 2m. By contrast, all tumors showed considerable expression of beta 2m after IFN therapy. Induction of class I antigens on tumor cells deficient in such expression may be one mechanism by which IFN exerts antitumor effects. We believe this is the first report of in vivo induction of class I MHC antigens in epithelial tumor cells in humans.
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PMID:Interferon-mediated in vivo induction of beta 2-microglobulin on small-cell lung cancers and mid-gut carcinoids. 301 23

Small cell carcinoma of the larynx is an uncommon neuroendocrine tumor with particular pathologic, therapeutic, and prognostic connotations. The first case of this lesion was observed in Canada in 1972. Fourteen cases of small cell carcinoma of the larynx were observed in the Ear, Nose, and Throat Department of Padua University in a series of 3,284 primary and secondary laryngeal and hypopharyngeal malignant neoplasms. This number constitutes the largest collection from a single institution in the literature and brings the total recorded cases to 66. The tumor is thought to arise from the argyrophilic Kulchitsky cells normally found in laryngeal mucosa. The diagnosis is based on the light microscopic appearance of the neoplasm and can be confirmed by electron microscopy. The differential diagnosis must be made from carcinoid, atypical carcinoid, small cell squamous carcinoma, small cell ductal carcinoma, lymphoma, mycosis fungoides, and metastatic lung small cell cancer. Systemic chemotherapy with radiation therapy is the accepted manner of treatment today. The survival of the patients treated with these modalities may be significantly improved, and some patients may be cured.
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PMID:Diagnosis and treatment of small cell carcinoma of the larynx: a critical review. 302 50

The case of a 32-year old man with exocrine pancreatic insufficiency and progressive weight loss is reported. Ultrasound examination of the abdomen revealed a huge tumor of the pancreatic head. Smears obtained by a percutaneous fine-needle biopsy showed characteristics of a neuroendocrine tumor. Serum hormone levels and immunocytochemistry presented no evidence for a hormonal activity of the tumor. The exocrine pancreatic insufficiency was explained by an obstruction of the pancreatic duct system. In the present case report the problems of diagnostic approaches to endocrine pancreatic tumors are discussed.
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PMID:[Endocrine pancreas tumor as a cause of exocrine pancreas insufficiency: problems of immunologic tumor diagnosis and classification]. 303 48

We have recently purified from bovine brain a 19-kDa protein, p19, that was previously shown to undergo hormonally regulated phosphorylation in several neuroendocrine tumor cells. We now report the tissue distribution of p19, studied by immunoblotting. Using a rabbit antiserum, which binds both to the unphosphorylated form and to the two predominant phosphoforms of p19, we show that the protein is present in brain and testis but not in a variety of other mammalian tissues. High levels of p19 are also present in several cultured tumor cells expressing neuroendocrine properties. In addition, p19 was detected in HL60 promyelocytic leukemia and in Friend erythroleukemia cells, but not in several other cell lines. In rat brain, we show that the level of p19 is maximal on the first postnatal day and declines within the first 2 weeks of life to a low plateau that persists into adulthood. The concentration of translatable p19 mRNA also decreases postnatally in rat brain, suggesting that the developmental regulation of the expression of p19 occurs, at least in part, at a pretranslational level. The broad species cross-reactivity of the p19 antibody suggests that the gene encoding p19 has been highly conserved during mammalian evolution. Based on the pattern of expression of this protein, we propose that p19 plays a role in the development of neurons and neuroendocrine cell types.
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PMID:Expression of phosphoprotein p19 in brain, testis, and neuroendocrine tumor cells. Developmental regulation in rat brain. 304 90

Four cases of Merkel cell tumor located in the face or on the trunk are presented. In a literature review 339 cases were found and analysed. The Merkel cell tumor is a neuroendocrine tumor of the skin derived from the Merkel cells. It is located most often in the face and neck area. Typically, it is an exophytic node, has a red-blue color and measures 25 mm in diameter on the average. Since it is metastasizing it is a malignant tumor. Regional node metastases were found in 27%, local recurrences occur in 51%, and distant metastases were seen in 32% of the cases. The best therapy is excision with wide margins as is the rule for a malignant skin tumor. While the tumor reacts to radiotherapy, chemotherapy seems to be of no help.
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PMID:[Clinical aspects and therapy of Merkel cell tumor--report of 4 personal cases and review of the literature]. 328 29

In view of the frequent reports of the increased expression of myc oncogenes in several neuroendocrine tumor types, we have investigated c- and N-myc expression in human medullary carcinoma, a malignant tumor derived from the neuroendocrine "C"-cell subpopulation of the thyroid gland. In situ nucleic acid hybridization was used to permit analysis not only of tumors but also of normal C-cells which form a tiny, scattered, minority of the thyroid epithelial cell population. N-myc expression was readily demonstrable in 6 of 21 tumor samples and c-myc in one case, whereas neither N- nor c-myc mRNA was ever detected in normal C-cells. We conclude that N-myc expression is a specific feature of C-cell tumors and is not merely a differentiation marker of their cell of origin. The data therefore strengthen the hypothesis that myc oncogene activation plays a role in neuroendocrine neoplasia.
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PMID:N-myc expression in neoplasia of human thyroid C-cells. 338 99

We constructed a human pheochromocytoma cDNA library and used differential hybridization to human pheochromocytoma and human neuroblastoma cDNA probes to isolate genes that are highly expressed in the adrenal medullary neuroendocrine tumor, pheochromocytoma, but not in the more immature embryonal tumor of adrenal medulla, neuroblastoma. Two cDNA clones, pG8 and pG2, were more highly expressed in normal and neoplastic chromaffin tissue than they are in neuroblastoma. Furthermore, they are expressed in a remarkably limited number of other human tumors or normal tissues. pG8 is highly expressed in medullary thyroid carcinoma, another tumor of neural crest origin, which can occur in association with pheochromocytoma in the multiple endocrine neoplasia type II syndrome. pG2 is highly expressed in the adrenal cortex, an endocrine gland thought to be embryologically unrelated to the neural crest-derived adrenal medulla. The expression of both pG8 and pG2 can be induced in human neuroblastoma cells with dexamethasone, suggesting a mechanism by which glucocorticoids may influence development of a neuroendocrine phenotype.
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PMID:Molecular markers of neuroendocrine development and evidence of environmental regulation. 347 Jul 97

The diagnostic value of computed tomography (CT) and iodine-131 meta-iodo-benzylguanidine (MIBG) scintiscanning was studied in nine patients with histologically proved carcinoid tumors of intestinal (n = 4), bronchial (n = 3), or thymic (n = 2) origin. CT scans clearly depicted the tumors and metastases in relation to surrounding vital structures but did not provide findings specific for carcinoids. The appearance on CT of an abdominal soft-tissue mass with a radiating pattern of linear densities was found to be highly suggestive of intestinal carcinoid tumors. I-131 MIBG scintiscans disclosed intense tracer uptake in the tumors and metastases in five patients. MIBG studies correctly depicted nine of nine tumor manifestations in intestinal carcinoids and four of six tumor manifestations in bronchus carcinoids. No MIBG concentration was found in thymus carcinoids. Because of its selective uptake mechanism, I-131 MIBG scintigraphy can allow specific detection and localization of neuroendocrine tumor tissue in patients with suspected carcinoid tumors. MIBG scintigraphy has diagnostic potential as a screening procedure in carcinoid tumors, especially those of intestinal origin.
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PMID:Carcinoid tumors: CT and I-131 meta-iodo-benzylguanidine scintigraphy. 358 4

Merkel cell carcinoma is a rare malignant neoplasm of the skin which is locally invasive and frequently metastasizes to lymph nodes, liver, lungs, bone, and brain. Computed tomographic and pathologic findings in an elderly woman with Merkel cell carcinoma of the buttock and regional nodal metastasis are reported. The presence of calcitonin and neuron-specific enolase within the tumor supports the theory that Merkel cell carcinoma is a neuroendocrine tumor derived from the APUD (amine precursor uptake and decarboxylase) system.
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PMID:Merkel cell carcinoma. 360 56


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