Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

After an acute episode of pancreatitis, a 63-year-old man was found to have a pancreatic glucagonoma. The tumor was resected without evidence of metastases. Three years later he had symptoms of uncontrolled diabetes, no skin lesions, and diarrhea and was found to have a pancreatic pseudocyst and multiple hepatic metastases. Glucagon concentrations were raised but were suppressible by glucose and somatostatin and responded to arginine stimulation. He was treated for 6 months with octreotide (Sandostatin), which reduced his symptoms; the pseudocyst resolved, but liver metastases continued to grow. Although spontaneous resolution of the pseudocyst is possible, this case appears to illustrate differences in sensitivity of endocrine and exocrine tissues to suppression by Sandostatin.
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PMID:Somatostatin analogue in treatment of coexisting glucagonoma and pancreatic pseudocyst: dissociation of responses. 216 87

Specific receptors for somatostatin (SS), mediating the various actions of this peptide, have been described in SS target tissues in animal and man. Using homogenate binding assays, as well as receptor autoradiography, the presence of SS receptors has been demonstrated in various regions of the brain (cortex, limbic system, basal ganglia), the anterior pituitary, the endocrine and exocrine pancreas, the gastrointestinal tract, and the adrenals. There are species-, as well as age-, related variations. Furthermore, there is evidence for different SS receptor subtypes. Interestingly, a large variety of human tumors also contain SS receptors with similar characteristics as those found in normal tissue; in numerous tumors, the SS receptor density is even higher than in healthy tissue counterparts. Most GH- and TSH-producing pituitary adenomas, but also a subgroup of endocrine inactive pituitary adenomas, have SS receptors; most carcinoids and islet cell carcinomas, as well as their metastases, also contain SS receptors. Several differentiated (usually EGF receptor negative) glia tumors possess SS receptors, whereas undifferentiated (EGF receptor positive) glia tumors lack such receptors. Furthermore, a subgroup of breast tumors, usually steroid receptor positive and neuroendocrine-differentiated, contain SS receptors. Finally, small cell lung carcinomas, but not non-small cell carcinomas, often possess SS receptors. These receptors are likely to be functional since in 11 acromegalics and 18 gastroenteropancreatic tumor patients, a positive correlation was observed between their SS receptor status and their hormone secretion sensitivity to Sandostatin.
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PMID:Distribution of somatostatin receptors in normal and tumor tissue. 216 75

The effect of an octapeptide analogue of somatostatin, octreotide, on tumor blood flow was evaluated with angiography in eight patients with hepatic endocrine tumors; one patient had primary intrahepatic gastrinoma, two patients had hepatic metastases from gastrinomas, two patients had VIPomas (vasoactive intestinal polypeptide-secreting tumor), and three patients had carcinoid tumors. Octreotide caused a marked decrease in tumor blood flow in two patients with gastrinomas and two with VIPomas. One patient could not be evaluated due to the lack of a tumor blush on a control angiogram. In patients with carcinoid tumors, octreotide caused a slight reduction in blood flow through the tumors in two patients, while there was no change in one patient. Octreotide markedly decreased gastrin and gastric acid secretion in two of three patients with gastrinomas, lowered VIP and stopped the diarrhea in patients with VIPomas, and controlled symptoms in two of three patients with carcinoid tumors. The vasoactive effect of octreotide on hepatic endocrine tumors may be a direct action on tumor blood supply or secondary to inhibition of the endocrine tumor cell secretion and consequent decreased blood flow.
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PMID:Effect of somatostatin analogue (octreotide) on blood flow to endocrine tumors metastatic to the liver: angiographic evaluation. 217 Oct 15

The definitive treatment of a pancreatic tumour secreting vasoactive intestinal polypeptide is surgical removal of the tumour, but when curative resection is not possible symptomatic treatment of the endocrine hyperfunction is important. Streptozotozin, although relative effective for palliation, may involve unpleasant side effects. A review of the literature and a case report with long-term use of subcutaneous somatostatin analogue SMS 201-995 in an elderly woman presenting with severe watery diarrhoea due to a pancreative vipoma is presented. Good symptomatic improvement was achieved with no side effects apart from tachyphylaxy to some extent over a period of 12 months. It is suggested that there is a use for subcutaneous SMS 201-995 in elderly patients with inoperable pancreatic gut hormone producing tumours with metastasis and in those in whom surgery would involve a high operative risk. Two cases are presented, where SMS 201-995 resulted in shrinkage of tumour and metastases.
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PMID:[The somatostatin analog SMS 201-995 in long-term treatment of vipoma]. 217 34

Because of its widespread distribution within the nervous system and gastroenteropancreatic (GEP) system, and its diverse physiological inhibitory actions on various gastrointestinal functions, including endocrine and exocrine secretion, motility, liver and splanchnic blood flow and absorption, native somatostatin has been viewed as a possible therapy for many diseases. However, its short duration of action and consequent limited clinical usefulness have been overcome with the availability of Sandostatin (octreotide, Sandoz Ltd), a long-acting, synthetic octapeptide analog of the naturally occurring hormone. Sandostatin represents a significant advance in the treatment of growth hormone (GH) and thyrotropin (TSH)-secreting pituitary tumors and GEP endocrine tumors (carcinoid tumor, VIPoma, glucagonoma, insulinoma, and gastrinoma). Preclinical in vitro and animal studies have shown the antineoplastic activity of the compound. Moreover, because of a possible direct effect on somatostatin receptor-positive endocrine tumor cells and an indirect effect whereby Sandostatin lowers GH, insulin-like growth factor type 1 (IGF-1), and numerous gastrointestinal peptides, Sandostatin may prove useful as an adjunctive therapy in cancer patients. In vivo labeling of somatostatin receptor-positive tumors with radiolabeled somatostatin analogs now allows localization of such tumors and their metastases. In addition, targeted irradiation of these tumors by beta particle-emitting isotopes attached to such somatostatin analogs may become possible. The use of Sandostatin in acute esophageal variceal bleeding, pancreatic pseudocysts, gastrointestinal, and pancreatic external fistulae, short bowel syndrome, dumping syndrome and acquired immunodeficiency syndrome (AIDS)-related refractory hypersecretory diarrhea has provided encouraging results.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Future medical prospects for Sandostatin. 220 87

In the present study of 45 patients with Zollinger-Ellison syndrome, the frequency and clinical importance of the release of multiple gastrointestinal peptides were assessed prospectively. During an initial evaluation, extent of gastrinoma, clinical symptoms, disease duration, and presence or absence of multiple endocrine neoplasia, type I (MEN-I) were assessed. All patients had determinations of fasting plasma gastrin, human pancreatic polypeptide, motilin, neurotensin, and somatostatin; 35 had determinations of insulin and gastrin-releasing peptide and 21 had determinations of glucagon. A plasma elevation of additional peptides besides gastrin was detected in 62%, with 44% having one, 18% having two, and 0% having three additional peptides elevated. Motilin was elevated in 29%, human pancreatic polypeptide in 27%, neurotensin in 20%, and gastrin-releasing peptide in 10%, whereas insulin, glucagon, and somatostatin were not elevated in any patient. The presence or absence of elevation of any peptide did not differ in patients with or without MEN-I, with gastrinoma size, with the presence or absence of metastatic disease, or with various clinical symptoms. Patients were assessed yearly for clinical evidence of a secondary symptomatic pancreatic endocrine tumor syndrome with a median follow-up of 146 and 84 months from onset or diagnosis, respectively. Only one patient (2% of patients) developed a second syndrome (rate, 2 patients per 100 patients observed for 10 years). These results demonstrate that the plasma elevation of multiple gastrointestinal peptides is common in patients with Zollinger-Ellison syndrome; however, the rate of developing a second symptomatic pancreatic endocrine tumor syndrome is much lower than generally believed. Furthermore, no evidence is found to support the conclusions that the detection of the plasma elevation of these peptides is clinically important in assessing MEN-I status, disease extent, or presence of metastatic disease or that elevated levels of motilin, neurotensin, gastrin-releasing peptide, or human pancreatic peptide are associated with any distinct clinical symptoms. Therefore, we recommend that plasma concentrations of these additional gastrointestinal peptides should not be assessed routinely but rather only if new symptoms develop.
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PMID:Multiple hormone elevations in Zollinger-Ellison syndrome. Prospective study of clinical significance and of the development of a second symptomatic pancreatic endocrine tumor syndrome. 222 72

Eighty-four carcinoids of the colon and rectum were studied with emphasis on prognostic features, immunohistochemical characteristics, and pitfalls in diagnosis. Follow-up data were available on 35 patients. Tumors with adenocarcinomatous components, or those resembling small cell carcinomas of the lung, were excluded. Eighty-one tumors were in the rectum and three tumors were in the distal sigmoid colon. Neuron-specific enolase, chromogranin, and Leu-7 were positive in 87%, 58%, and 53% of the tumors, respectively. Hormones were positive in the following percentages: serotonin, 45%; pancreatic polypeptide, 46%; glucagon, 10%; gastrin, 3%; somatostatin, 3%; adrenocorticotrophic hormone, 1%; cholecystokinin, 0%; calcitonin, 0%; and insulin, 0%. Many tumors elaborated more than one hormone. Fifty-five percent of the tumors were argyrophil and 28% were argentaffin. Carcinoembryonic antigen was present in 24% of the tumors; 82% of the tumors contained prostatic acid phosphatase. Three patients had liver metastases; their tumors ulcerated, invaded muscularis propria, and had more than 2 mitoses per 10 high-power fields (HPF). One patient with a 2.5-cm tumor without mitoses had regional lymph node metastases. All non-metastasizing tumors had less than one mitosis in 10 HPF. We conclude that large bowel carcinoid tumors are essentially limited to the rectum and sigmoid, that they are indolent if mitotically inactive and smaller than 2 cm, and that most show production of a selected group of endocrine markers.
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PMID:Rectal and colonic carcinoids. A clinicopathologic study of 84 cases. 229 59

The nuclear DNA content of 17 pancreatic neuroendocrine tumors was measured from paraffin-embedded tissue with flow cytometry. The tumors were classified by immunostaining with antisera for synaptophysin, insulin, gastrin, glucagon, pancreatic polypeptide, somatostatin, and vasoactive intestinal polypeptide. Eight (47%) of the 17 tumors were aneuploid, and two (12%) were multiploid (had two aneuploid stemlines of cells). Seven of the eight insulinomas, one of the four gastrinomas, and two of the four nonspecified neuroendocrine tumors had an abnormal nuclear DNA content. The DNA indices of the aneuploid and multiploid cases ranged from 1.13 to 1.93, and three cases had a DNA index greater than 1.50. During the follow-up for up to 16 years (mean, 7 years), one patient with diploid nonspecified tumor died of the disease, another patient with a multiploid gastrinoma had metastatic disease develop, and a third patient with a multiploid nonspecified tumor was alive with the disease. The authors conclude that many neuroendocrine tumors of the pancreas have an abnormal nuclear DNA content as measured by DNA flow cytometry. DNA multiploid pancreatic neuroendocrine tumors may be associated with a less favorable clinical course, but this needs to be confirmed in additional studies.
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PMID:DNA ploidy in pancreatic neuroendocrine tumors. 234 35

Three monoclonal IgG 2a antibodies were produced after immunization of mice with dispersed cells from a human mid-gut carcinoid tumor. Acetone-fixed cryosections of 57 primary and metastatic mid-gut carcinoid tumors as well as 2 hind-gut (rectal) carcinoids showed a conspicuous immunoreaction while a thymic carcinoid was essentially unstained with the antibodies. The 3 antibodies yielded a similar pattern of immunostaining. The immunoreaction comprised more than 95% of the carcinoid tumor cells, and it was more uniform and intense in primary tumors than in mesenteric, hepatic, and ovarian metastases of the mid-gut carcinoid tumors. Immunofluorescence studies on suspended carcinoid tumor cells showed that the antibodies bound to the surface membrane of the cells. The antibodies immunostained enterocytes of the small and large bowel, intestinal metaplasia of the stomach mucosa as well as colorectal adenocarcinomas. Endocrine pancreatic tumors producing vasoactive intestinal polypeptide, gastrin, somatostatin, and/or pancreatic polypeptide as well as the epithelium of pancreatic ducts were also stained with the antibodies, whereas a large number of other normal and abnormal human tissues, including benign and malignant insulinomas, were unreactive. The findings indicate that the antibodies recognize differentiation antigens on the carcinoid tumor cell surface preserved also on endocrine and nonendocrine cells of the normal bowel mucosa. The restricted tissue reactivity of the antibodies suggests that they may constitute useful tools in the histological characterization of carcinoid tumors. Further studies may reveal if they are applicable for immunolocalization and perhaps even immunotherapy of these neoplasms.
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PMID:Monoclonal antibodies raised against mid-gut carcinoid tumor cells. 236 42

Several years of clinical chemotherapy have shown that, despite modern refinements, cytotoxic agents are not able to eradicate metastases of most adult solid tumors but only to prolong survival by achieving a cell kill that is not 100 per cent. Among the possible causes of this phenomenon, two are discussed in detail. The first one is cell autonomy. It is shown that the numbers of generations reached by a metastatic clone until clinical detection is largely in excess of 100, which allows for a considerable number of mutations, and that in addition genetic destabilization leading to autonomy proceeds much more rapidly than anticipated by a random mutation process. Adaptative changes by genetic amplification in response to toxic injury add to this acceleration effect, accounting for the fact that most metastatic cells are totally resistant very early in the natural history of a human tumor. On the other hand, it is shown that dormant metastatic cells do exist, due either to lack of autocrine growth factors or to inhibiting agents secreted by other metastases. These cells can survive chemotherapy and then re-enter a proliferative state due to some mechanisms that are analyzed, accounting for semi-late and late failures. These obstacles call for other strategies of metastases management, such as arresting or differentiating agents, some of which have been successfully tested by the author's group, such as antiprostaglandins, antithrombin, somatostatin, hyaluronidase, and retinoic acid. It remains to study their optimal combinations, and the appropriate timing, in order to achieve, if not eradication, growth suppression for very long periods without toxicity.
Clin Exp Metastasis
PMID:Accelerated genetic destabilization and dormancy: two distinct causes of resistance in metastatic cells; clinical magnitude, therapeutic approaches. 240 88


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