Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P61278 (somatostatin)
 22,083 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Two patients with neurofibromatosis and somatostatinoma are described, one patient in addition having a parathyroid adenoma diagnosed post mortem. The other patient had a partial somatostatinoma syndrome with diabetes, abdominal pain and cholelithiasis. The tumour was diagnosed preoperatively and metabolic studies demonstrated mild diabetes mellitus apparently due to suppression of insulin secretion by somatostatin, since oral glucose tolerance returned to normal post-operatively despite hemipancreatectomy. The tumour also secreted gastrin. There are now 18 reported cases of neurofibromatosis and duodenal carcinoid tumours which makes a genuine association between these two conditions very likely. With the present two cases, seven of the carcinoid tumours in this group have been positively identified as somatostatinomas. The histological finding of psammoma bodies is important in the diagnosis of duodenal somatostatinomas.
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PMID:Neurofibromatosis associated with somatostatinoma: a report of two patients. 290 5

Plasma somatostatin response to food and the administration of the long-acting somatostatin analogue SMS 201-995, as well as pituitary responses to insulin-induced hypoglycemia, growth hormone-releasing hormone (GHRH) and thyrotropin-releasing hormone (TRH), were assessed in a 60-year-old woman with biopsy-proven metastatic somatostatinoma. SMS 201-995 alone did not change plasma somatostatin-like immunoreactivity (SRIF), but levels of low-molecular-weight forms (SRIF-14 and SRIF-28) more than doubled in response to a standard meal. This postprandial response was not affected by pretreatment with SMS 201-995. Although a growth hormone response to insulin-induced hypoglycemia and supramaximal GHRH was absent, the patient's thyroid-stimulating hormone response to TRH was normal. These results suggest that somatostatin analogues may not influence tumor autonomy and that a SRIF response to food may contribute to early satiety in patients with somatostatinoma. In addition, the long-term use of somatostatin analogues to suppress hormone production by other peptide-secreting tumors may not have predictable results.
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PMID:A case of somatostatinoma: responses to food and SMS 201-995 administration. 290 26

We describe a patient with a small somatostatinoma of the papilla of Vater without clinical evidence for diabetes mellitus, diarrhea, steatorrhea, or cholelithiasis, showing normal plasma basal levels for somatostatinlike immunoreactivity. The diagnosis was based on histologic and immunohistochemical analysis of tumor tissue and hypersomatostatinemia induced by the calcium-pentagastrin test. Before removal of the tumor both diagnostic tests recommended for the detection of a somatostatinoma, a tolbutamide test and a calcium-pentagastrin test, were performed. Whereas the calcium-pentagastrin test provoked a markedly elevated plasma somatostatin level in association with a depressed plasma neurotensin level, the tolbutamide test surprisingly did not. After removal of the tumor the calcium-pentagastrin test no longer induced hypersomatostatinemia. Further studies are needed to determine whether the calcium-pentagastrin test is a more reliable diagnostic test than the tolbutamide test in somatostatinomas with normal plasma basal levels.
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PMID:Comparative diagnostic value of the calcium-pentagastrin test versus the tolbutamide test in a patient with a somatostatinoma. 302 98

Twenty mucinous cystadenocarcinomas of the pancreas, most of which occurred in the tail of the pancreas in middle-aged women, were examined histologically and by immunohistochemical stains. Thirteen tumors displayed a marked histological heterogeneity and expressed intestinal differentiation as shown by the colonic appearance of the glands both at the light- and electron-microscopic levels. Other intestinal features included varying numbers of goblet cells, argyrophil and argentaffin cells, and even Paneth cells. By immunohistochemistry, endocrine cells were present in 13 of the 20 tumors (65%) and were more numerous in the poorly differentiated than in the well-differentiated epithelial component of the tumors. Serotonin-containing cells were the most common endocrine cells, followed by somatostatin-containing cells and cells that showed immunoreactivity for pancreatic polypeptide and gastrin. However, none of the patients had clinical manifestations of carcinoid, somatostatinoma, or the Zollinger-Ellison syndrome. The findings support the hypothesis that mucinous cystadenocarcinomas of the pancreas arise from an "endodermal stem cell" that differentiates into cells with intestinal phenotypes.
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PMID:Mucinous cystadenocarcinoma of the pancreas. Morphologic and immunocytochemical observations. 378 55

A pancreatic somatostatinoma metastatized to the liver was detected in a 70-yr-old woman presenting with chronic diarrhea, steatorrhea, pancreatic insufficiency, diabetes mellitus, and achlorhydria. At immunocytochemistry, most tumor cells stored both somatostatin and calcitoninlike substances. Chromatography of acid extracts of the tumor on G50 Sephadex gave two distinct peaks coeluting with cyclic ovine somatostatin and human calcitonin, respectively, thus ruling out the hypothesis of a single cross-reacting molecule synthetized by the neoplastic cells. When the tumor was extracted at neutral pH, larger molecular forms of the above components were found, which accounted for less than 20% of the total immunoreactivity. Gel permeation of plasma showed that the circulating calcitonin- and somatostatinlike components consisted of three and four different forms, respectively, including components of molecular weights similar to those of the reference peptides. Inhibition curves and immunoadsorption experiments indicated that the large forms were immunologically similar, if not identical, to the corresponding standard preparations. The present case illustrates the occasional ability of neoplastic somatostatin cells of pancreas to synthetize simultaneously components immunologically related to somatostatin and calcitonin. These two inappropriate secretions could account for the symptoms displayed by this patient.
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PMID:Calcitonin-producing pancreatic somatostatinoma. 610 50

Somatostatin-like immunoreactive polypeptides with approximate molecular weights of 1,500-2,000 (peak I), 2,500-3,500 (peak II), and 10,000-15,000 (peak III) were isolated from the peripheral plasma and from extracts of tumor tissue of a patient with a pancreatic somatostatinoma and hepatic metastases. The peak I component had approximately the same molecular charge as somatostatin, but the peak II component was appreciably more basic. The peak III component was heterogeneous with respect to charge and dissociated into smaller immunoreactive polypeptides during isoelectric focusing or after treatment with strongly denaturing solvents. In plasma, the levels of the larger molecular weight components (peak II and peak III), relative to that of the somatostatin-size component (peak I), were higher than in tissue extracts, suggesting a lower rate of clearance of the larger polypeptides from the circulation. In response to a nutrient stimulus, the peak I component increased to a greater extent than the larger components. Plasma levels of larger immunoreactive polypeptides relative to the peak I component in patient's plasma were higher after complete resection of the pancreatic tumor than preoperatively, suggesting that the rate of release of these putative precursor forms from the metastases was greater than from the primary tumor.
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PMID:Characterization of somatostatin-like components in the tumors and plasma of a patient with a somatostatinoma. 610 68

Previous evidence has documented the hyperglycemia and glucose intolerance that occur during prolonged infusions of somatostatin and in patients with somatostatinoma. We studied glucose utilization and production and gluconeogenesis (from alanine) in a patient with the somatostatinoma syndrome (peripheral somatostatin levels 20,000 pg/ml) during saline (basal state) and glucose infusion (1.78 mg/kg . min). Plasma glucose levels increased from 163 to 229 mg/100 ml during glucose infusion, whereas lactate, free fatty acid, and glucagon levels did not change. Endogenous glucose production decreased from 7.34 to 0.0 mumol/kg . min, and the percentage of glucose derived from alanine also decreased from 10.5 to 7.4. Glucose clearance decreased from 0.81 to 0.74 cc/kg . min and suggests that the hyperglycemia of the somatostatinoma syndrome is secondary to reduced peripheral glucose utilization secondary to relative insulin deficiency.
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PMID:Glucose turnover and gluconeogenesis in a patient with somatostatinoma. 611 Feb 46

RNA has been isolated from a human pancreatic somatostatinoma and used to prepare a cDNA library. After prescreening, clones containing somatostatin I sequences were identified by hybridization with an anglerfish somatostatin I-cloned cDNA probe. From the nucleotide sequence of two of these clones, we have deduced an essentially full-length mRNA sequence, including the preprosomatostatin coding region, 105 nucleotides from the 5' untranslated region and the complete 150-nucleotide 3' untranslated region. The coding region predicts a 116-amino acid precursor protein (Mr, 12.727) that contains somatostatin-14 and -28 at its COOH terminus. The predicted amino acid sequence of human somatostatin-28 is identical to that of somatostatin-28 isolated from the porcine and ovine species. A comparison of the amino acid sequences of human and anglerfish preprosomatostatin I indicated that the COOH-terminal region encoding somatostatin-14 and the adjacent 6 amino acids are highly conserved, whereas the remainder of the molecule, including the signal peptide region, is more divergent. However, many of the amino acid differences found in the pro region of the human and anglerfish proteins are conservative changes. This suggests that the propeptides have a similar secondary structure, which in turn may imply a biological function for this region of the molecule.
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PMID:Human somatostatin I: sequence of the cDNA. 612 75

Five cases of somatostatinoma are reported, four being primarily located in the pancreas and one in the duodenum. The diagnosis was based upon the histological and immunochemical characteristics of tumoral and metastatic tissue. A marked clinical heterogeneity was noted: one patient presented with gallstones, steatorrhea, and diabetes, two patients suffered from severe hypoglycemic attacks, and two cases were admitted for obstructive jaundice. This varying symptomatology was related to differences in the circulating levels of biologically active somatostatin and to a variable cellular composition of the tumor. In all cases, a basal and/or tolbutamide-induced hypersomatostatinemia was measured. It is concluded that the clinical and hormonal features of the earlier defined somatostatinoma syndrome are no requisite for the diagnosis of somatostatinoma; the analysis of plasma somatostatin immunoreactivity might lead to a higher detection rate of this endocrine tumor.
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PMID:Five cases of somatostatinoma: clinical heterogeneity and diagnostic usefulness of basal and tolbutamide-induced hypersomatostatinemia. 613 27

A case of somatostatinoma syndrome in a 30-year-old woman is presented. Basal levels of growth hormone and of pancreatic and gastric hormones were reduced and the response of growth hormone, insulin and C-peptide to stimuli such as arginine, glucose, glibenclamide and calcium was virtually abolished. Similarly, gastric acid secretion, pancreatic exocrine function and intestinal absorption were significantly reduced. On the other hand, basal and stimulated levels of adrenocorticotropic hormone (ACTH), luteinizing hormone (LH), follicle-stimulating hormone (FSH) and thyroid-stimulating hormone (TSH) were within the normal range. Plasma somatostatin-like immunoreactivity was increased to 600-2,000 pg/ml (normal: 88-140 pg/ml). Immunocytochemical studies demonstrated the presence of somatostatin immunoreactive material in the primary tumour in the head of the pancreas and in the liver metastases. In spite of two courses of chemotherapy with streptozotocin and 5-fluorouracil the patient died due to liver failure 5 months after the first admission to hospital.
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PMID:Somatostatinoma syndrome. Clinical, morphological and metabolic features and therapeutic aspects. 613 27


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