Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01350 (gastrin)
 9,683 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

During 1980, percutaneous transhepatic portal vein catheterisation was carried out in eight patients with suspected hormone-producing tumours in an attempt to localise these. Seven patients with hyperinsulinism were suspected of having an insulinoma and one a gastrinoma. There were no complications following the catheterisation, and difficulties were reduced by the use of a special catheter. The blood samples were examined by radio-immunological methods for insulin or gastrin. On the basis of localised rise in hormone level, it was possible to diagnose three insulinomas and one gastrinoma in the pancreas. The beta-cell tumours were removed by enucleation or segmental resection, the gastrinoma by a Whipple's operation. Three patients showed an insulin gradient and sub-total pancreatectomies were performed. In one patient there was no definite abnormality in the insulin level and an operation has so far not been performed. Our experience indicates that this technique is difficult, bu is nevertheless a reliable method for localising hormone-producing tumours and surgery should not be carried out without it.
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PMID:[Percutaneous transhepatic portal vein catheterisation in the diagnosis of hormone-producing tumours in the splanchnic area (author's transl)]. 628 31

The authors report the case of a patient with a typical carcinoid syndrome and a severe hypoglycemia due to hyperinsulinism. He was found to have an ileal carcinoid tumor with hepatic metastasis and no evidence of pancreatic insulinoma at surgery and autopsy. By assaying serotonin and insulin in the tumor and in the supernatants of the culture derived from hepatic metastasis, the authors have been able to show that both hormones were produced by the carcinoid tissue. Cultured cells also synthesized minute amounts of gastrin and thyrocalcitonin.
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PMID:Serotonin-secreting and insulin-secreting ileal carcinoid tumor and the use of in vitro culture of tumoral cells. 637 87

Three patients with the watery diarrhea-hypokalemia-achlorhydria (WDHA) syndrome were studied. All had watery diarrhea, hypokalemia and hypercalcemia. Plasma vasoactive intestinal polypeptide (VIP) levels determined by radioimmunoassay were markedly elevated in these patients, indicating that they had VIP-producing tumors. Plasma VIP levels determined serially after the operation indicate that its determination is useful in estimating the effect of a treatment. As for multiple endocrine neoplasia type 1 (MEN1), two out of the three cases belonged to this category. Patient 1 had a brother with insulinoma, and in case 2, even though there was no family history, the autopsy revealed not only multiple tumors of the pancreas but also pituitary adenomas, chief cell hyperplasia of the parathyroid glands, thyroid adenomas and adrenocortical adenomas. VIP and other hormones in the tumors as well as in the plasma were examined extensively in these cases. In case 1, VIP, gastrin and calcitonin were produced in the tumor and only plasma VIP levels were elevated. In case 2, with multiple tumors, tumor 1 produced VIP, glucagon pancreatic polypeptide, gastrin and calcitonin, and tumor 2, VIP, pancreatic polypeptide, gastrin and beta-melanocyte stimulating hormone. In this case, plasma VIP, pancreatic polypeptide and glucagon levels were elevated. In case 3, VIP and calcitonin were produced in the tumor, and plasma VIP and calcitonin levels were elevated. These results indicate that (1) VIP is a good tumor marker for the WDHA syndrome due to VIP-producing tumors; (2) patients with the WDHA syndrome are sometimes associated with MEN1; and (3) VIP-producing tumors are multiple hormone-producing tumors, and VIP predominantly elevated in the plasma results in the WDHA syndrome, although other hormones such as pancreatic polypeptide, glucagon and calcitonin are sometimes found to be elevated in plasma without contributing to the clinical features.
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PMID:Clinical and hormonal aspects of the watery diarrhea-hypokalemia-achlorhydria (WDHA) syndrome due to vasoactive intestinal polypeptide (VIP)-producing tumor. 701 8

Gastropancreatic neuroendocrine cells synthesize large amounts of gamma-aminobutyric acid (GABA). This amino acid neurotransmitter appears to be stored in and released from, vesicles similar to small synaptic vesicles. So far, the function of GABA in gastropancreatic, neuroendocrine cells has not been clarified. Previous work suggested that only pancreatic, glucagon-producing alpha 2 cells contain functional GABAA receptors. Using subunit-specific antibodies in sections of human antral mucosa, a human gastrinoma and rat pancreas, we show that expression of GABAA receptors is abundant in gastropancreatic, neuroendocrine cells. Using the patch-clamp technique in the whole-cell mode we demonstrate that both the rat insulinoma cell line RIN 38 and the amphicrine cell line AR42J express functional GABAA receptors, which are characterized by a relatively low benzodiazepine and Zn2+ sensitivity and by an insensitivity to the inverse benzodiazepine agonist 6,7-alpha-methoxy-4-ethyl-beta-carboline-3-carboxylate (DMCM). In contrast to neurons, activation of GABAA receptors leads to a membrane depolarization. This depolarization presumably activates voltage-gated Ca2+ channels, resulting in an increase in cytosolic Ca2+ concentration, [Ca2+]i, as shown with the fluorimetric dye fura-2. The combination of GABA release, GABAA receptor activation and the [Ca2+]i increase could constitute an autocrine mechanism, modulating the release of hormones such as gastrin, insulin and somatostatin.
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PMID:Expression of functional GABAA receptors in neuroendocrine gastropancreatic cells. 749 Dec 62

The gastrin gene is transiently expressed in fetal pancreatic islets during islet neogenesis but then switched off after birth when islet cells become fully differentiated. Previous studies identified a cis-regulatory sequence between -109 and -75 in the human gastrin promoter which binds islet cell-specific activators and a nonspecific repressor and thus may act as a molecular switch. The present study identified another cis-regulatory sequence (-163ACACTAAATGAAAGGGCGGGGCAG-140) which bound two islet nuclear proteins in a mutually exclusive manner, as defined by gel shift competition, methylation interference, and DNase I foot-printing assays. The general transactivator Sp1 recognized the downstream GGGCGGGG sequence, but Sp1 binding was prevented when another islet factor bound to the adjacent AT-rich sequence (CTAAATGA). This gastrin AT-rich element is nearly identical to the binding site (ATAAATGA) for the islet-specific transcription factor beta TF-1. However, the gastrin AT-binding factor appeared to differ from beta TF-1 in its gel mobility shift pattern. Transfections of rat insulinoma cells revealed that mutations which blocked binding to the AT-rich element but allowed Sp1 binding up-regulated transcriptional activity. These results suggest that the gastrin AT-binding factor blocks transactivation by Sp1 and may have a role in the repression of gastrin transcription seen at the end of islet differentiation.
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PMID:Mutually exclusive interactions between factors binding to adjacent Sp1 and AT-rich elements regulate gastrin gene transcription in insulinoma cells. 772 90

Although IAPP was first discovered and isolated from amyloid deposits in an endocrine pancreatic tumour (EPT), surprisingly few reports have investigated the potential use of IAPP as a marker for neuroendocrine tumour growth. In this study we present results from plasma measurements of IAPP in 102 patients with neuroendocrine tumours. Four of 35 patients (11%) with midgut carcinoid tumours, but none of the patients (4 and 5, respectively) with lung carcinoids or with rectal carcinoids displayed elevated plasma levels of IAPP. Five of 31 patients (16%) with sporadic EPT and 3 of 27 patients (11%) with EPT and multiple endocrine neoplasia type 1 syndrome disclosed elevated IAPP levels. Within the different syndromes, 1/11 individuals with insulinoma, 2/16 with gastrinoma, 0/2 with glucagonoma, 0/3 with VIPoma and 5/26 with non-functioning tumours showed elevated plasma levels of IAPP. In two patients, the plasma IAPP levels were extremely elevated. These patients also exhibited altered glucose homeostasis. In response to a standardised mixed meal test, IAPP increased in parallel to the insulin, pancreatic polypeptide, gastrin and glucose responses. In MEN1 patients with hypercalcaemia due to increased secretion of parathyroid hormone, the plasma levels of IAPP were significantly higher before than after surgical removal of the parathyroid adenomas. However in normocalcaemic patients, no correlation between the blood calcium and plasma IAPP levels was found. Immunocytochemical staining of tumour tissue showed that 9/13 (69%) of insulin producing tumours, 4/14 (29%) of non-functioning tumours and 1/9 (11%) of gastrin producing tumours were IAPP immunoreactive. Amyloid deposits were always IAPP immunoreactive. In conclusion, increased circulating levels of IAPP occurred in 12% of 102 patients with neuroendocrine tumours. In 2 patients with extremely elevated plasma levels of IAPP, effects on glucose homeostasis were recorded. Thus, IAPP may be useful as an additional marker for neuroendocrine tumour growth in selected cases.
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PMID:Islet amyloid polypeptide (IAPP) in patients with neuroendocrine tumours. 775

Location of gastrinomas by means of portal venous sampling is a technique in which venous blood from various sites in the portal system around the pancreas and duodenum is obtained and assayed for gastrin levels. A gradient of 50% or greater compared to systemic gastrin levels from a given location regionally identifies the site of gastrin overproduction, thereby locating the tumor. The only area in which venous sampling may help, in the authors' opinion, is in the small subset of patients who have occult gastrinoma not imaged with any other modality, in the body or tail of the pancreas that cannot be found with intraoperative ultrasound or palpation. It is considered that a secretin angiogram is equally effective and is a simpler procedure. Similarly, in insulinoma regional location of the tumor by means of a calcium angiogram has eliminated the usefulness of portal venous sampling. Controversial areas of surgical treatment of APUDomas often reflect a balance between the risks and benefits of aggressive surgery, as data to support an aggressive surgical approach to obtain improved survival often do not exist. For example, if patients with occult MTC can undergo cervical reexploration with minimal or no morbidity the potential benefit of removing malignant disease, warrants this approach. Similarly, if patients with MEN-1 can be explored safely with resection of pancreatic and duodenal tumors, then this position can be defended. On the other hand, if a subgroup of patients with MEN-2 and pheochromocytomas can be spared bilateral adrenalectomy without compromising their long-term outcome in terms of disease-free survival, then this conservative approach is warranted.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Controversies in surgical therapy for APUDomas. 790 10

Thrombosis of the left subclavian vein occurred in a 44-year-old man. It was found to be caused by an atypical thymus carcinoid of the anterior mediastinum without carcinoid syndrome. Primary resection was not possible, but it was removed after three cycles of neoadjuvant chemotherapy with doxorubicin, cisplatin, vincristine and cyclophosphamide. Increased concentrations of alkaline phosphatase and parathormone were then noted. Subtotal parathyroidectomy revealed hyperplastic parathyroids. A gastrinoma was suspected from a history of peptic ulcer for many years which had persisted despite a Billroth II gastric resection 10 years ago. Serum gastrin, analysis of gastric secretion and a secretin-stimulating test confirmed the diagnosis. Recurrent episodes of weakness and syncope, in the presence of low blood sugar levels and a positive C-peptide suppression test, were interpreted as due to an insulinoma. There was no evidence of increased hypophyseal or adrenal function. Finally, in the absence of a family history, multiple endocrine neoplasia type 1 (MEN 1) was diagnosed with co-existing primary hyperparathyroidism, gastrinoma, insulinoma and thymus carcinoid. Somatostatin-receptor scintigraphy provided localization of the MEN 1 with enrichment in the thorax and abdomen.
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PMID:[Thymus carcinoid in multiple endocrine neoplasms type I]. 790 23

The clinical investigations carried out in a 58 years woman complaining of malaise led to the discovery of an hypoglycaemia resulting from a secreting pancreatic insulinoma. In addition, a chronic pancreatitis, an endocrine hyperplasia (possible nesidioblastosis) and a villous adenomatosis of the pancreatic duct were diagnosed on two biopsies. The immunohistological tests performed on the insulinoma showed insulin, calcitonin and gastrin labelled cells. Electron microscopy displayed numerous neurosecretory granules. The peritumoral endocrine hyperplasia contained intermingled B, A and D cells respectively labelled by insulin, glucagon and somatostatin. Following the operation, the patient recovered without recurrence of the hypoglycaemia (three year follow-up). Factors which may explain such a rare pathological association are discussed.
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PMID:[Pancreatic insulinoma, adenomatosis of the Wirsung's duct and chronic pancreatitis. Apropos of a case]. 813 87

The authors report their experience with octreotide in 20 patients (median age 57 years, 10 M, 10 F) from 1984 to 1991; 16 had metastatic APUDoma: 1 PPoma with VIPoma, 1 glucagonoma, 5 gastrinoma including 1 associated to PP-oma, 9 mid-gut carcinoid; 3 patients had multiple-endocrine neoplasia type I (MEN-I) with Zollinger-Ellison syndrome (ZES) and 1 patient a non-metastatic VIPoma. Octreotide (200-750 micrograms/day) was administered bid or tid with regular laboratory controls and morphological assessment. There was a striking improvement of symptoms, particularly in the carcinoid group (reduction of flushing in all patients and of diarrhoea in 3/5), in the patient with gastrinoma + acromegaly (regression of congestive heart failure) and in the patient with non-metastatic VIPoma. The hormonal markers were markedly reduced, particularly gastrin, PP (except in the patient with PPoma + VIPoma), VIP, GH and Somatomedin-C and urinary 5HIAA in 4/9 patients with carcinoid. There was only one partial regression of metastases (gastrinoma) and 4 apparent stabilizations of tumour growth, in the 16 metastatic cases. Among them, 4 patients died: 1 glucagonoma, 1 PPoma + VIPoma, 2 mid-gut carcinoids after a treatment of 5, 16, 30, 36 months, respectively. The patient with acromegaly + ZES died after 6 years of treatment at age 81. A patient with prolactinoma, resected insulinoma, hyperparathyroidism and ZES was not improved by a short course of octreotide (hypoglycemia); he died later of recurrent insulinoma. In conclusion, octreotide is a useful drug to control most of the symptoms related to gut endocrine tumours; it may inhibit tumour growth.
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PMID:Use of octreotide in the treatment of digestive neuroendocrine tumours. Seven year experience in 20 cases including 9 cases of metastatic midgut carcinoid and 5 cases of metastatic gastrinoma. 826 71


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