Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P01275 (glucagon)
 26,492 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Immunohistochemistry was performed on biopsies of columnar mucosa from 11 patients with Barrett's esophagus and 11 patients with columnar mucosa in the cranial esophagus, the "inlet patch." Both epithelia contained endocrine cells, immunoreactive to antisera against serotonin, glucagon, somatostatin, and pancreatic polypeptide; the specialized mucosa of Barrett's esophagus contained, in addition, neurotensin-immunoreactive cells, and in the mucosa of an inlet patch we found a gastrin cell. These findings are not compatible with some of the current theories on the origin of these epithelia. The mucosa of the inlet patch has been considered to consist of heterotopic gastric mucosa. The mucosa of the adult human stomach, however, does not contain glucagon cells. These cells are only present in the early embryonic stomach, and they disappear during embryonogenesis. According to our findings, the mucosa of the inlet patch therefore represents embryonic gastric mucosa. The specialized columnar epithelium of Barrett's esophagus has been considered to have evolved from gastric mucous neck cells. However, although glucagon cells are a feature of the embryonic stomach, neurotensin-immunoreactive cells have not been found in the gastric mucosa. Our study suggests that the specialized columnar epithelium of Barrett's esophagus originates from a very immature multipotent gastrointestinal stem cell.
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PMID:Distinct immunohistochemical findings in columnar epithelium of esophageal inlet patch and of Barrett's esophagus. 229 98

In order to characterize the differentiation of endocrine cells present in Barrett's oesophagus and to determine if they express a single or multiple hormonal pattern, endoscopic biopsies were taken from both the lesion and the fundus of 45 patients and studied at the light microscopical level. Conventional histology revealed three different epithelial patterns: gastric atrophic fundic, intestinal and junctional. A mixture of these patterns was present in 28 cases (62%) and the single type was identified in 17 cases (38%). The use of three silver staining methods and antibodies to human chromogranins allowed us to identify numerous endocrine cells in all but 1 case. Eleven sera against all the most common hormones stored in the endocrine cells of the gut were used to identify the main products of the cells. The following immunoreactivities were identified: 5-hydroxytryptamine (5-HT) (in 75% of the studied cases), somatostatin (87%), motilin (31%), pancreatic polypeptide (PP) (20%), glucose-dependent insulinotropic polypeptide (20%), gastrin (15%), glucagon (15%), peptide tyrosine tyrosine (13%), secretin (7%) and neurotensin (2%). No cholecystokinin-immunoreactive cells were identified. Our results indicated that, in Barrett's epithelium, both gastric and intestinal endocrine cells differentiate, in accordance with the variability of differentiation in the non-endocrine cells present in the different types of columnar epithelium. These findings provide support for the conclusion that Barrett's epithelium arises from a pluripotential stem cell capable of both gastric and intestinal differentiation.
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PMID:A mixed pattern of endocrine cells in metaplastic Barrett's oesophagus. Evidence that the epithelium derives from a pluripotential stem cell. 244 38

Barrett's epithelium refers to the presence of ectopic mucosal types in the squamous-lined oesophagus. Previous studies have documented argentaffin and argyrophil-positive cells as well as gastrin-like immunoreactivity in oesophageal tissue extracts from patients with Barrett's mucosa. In the present study, 125 oesophageal biopsies obtained under direct vision at endoscopy from 22 patients with Barrett's oesophagus were systematically studied using fluorescence and peroxidase antiperoxidase single and double-staining immunocytochemical methods employing highly specific antibodies to localize the following peptide-containing cell types in Barrett's mucosa: gastrin, somatostatin, gastric inhibitory polypeptide, motilin, neurotensin and pancreatic glucagon. In addition, EC cells were localized using a cytochemical silver staining method. The results of this study indicate that EC cells and gastrin- and somatostatin-containing endocrine cells are detectable in Barrett's epithelium.
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PMID:Regulatory peptides in Barrett's oesophagus. 286 40

While pancreatic metaplasia has been observed in gastric mucosa of patients with chronic gastritis, it has not been described in ectopic gastric mucosa. We have identified focal clusters of cells resembling pancreatic acinar cells (CPACs) in 11 of 350 biopsies of Barrett's mucosa from 120 patients with Barrett's esophagus enrolled in a clinical efficacy trial of omeprazole versus ranitidine for treatment of gastroesophageal reflux disease. Three additional cases from our surgical files were also studied. Immunoreactivity for trypsin and chymotrypsin was present in the CPACs of all 14 cases, while stains for alpha-amylase and lipase were each positive in 12 of 13. A few cells in the CPACs were also positive for chomogranins (12 of 13 cases), serotonin (seven of 13 cases), somatostatin (three of 12), gastrin (four of 11), and pancreatic polypeptide (two of 13). No staining was seen for insulin or glucagon. Ultrastructural studies performed in one case showed features of pancreatic exocrine and endocrine (PP-type) cells in cells within CPACs. These results collectively indicate that the CPACs are aggregates of true pancreatic acinar cells admixed with a few endocrine cells. This pancreatic parenchyma in Barrett's mucosa is most likely of metaplastic origin and could be derived from the transitional zone cells or from pluripotent stem cells in the esophageal mucosa or from metaplasia of mucus cells. While the development of pancreatic metaplasia in Barrett's esophagus appears to be unrelated to drug therapy, the clinical relevance of this distinctive histological finding needs further investigation.
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PMID:Pancreatic metaplasia in Barrett's esophagus. An immunohistochemical study. 757 75

Several case reports have emphasized that esophageal carcinoid tumors are associated with a poor prognosis. To expand our knowledge about the pathology and biologic behavior of these rare tumors, we reviewed the clinicopathologic and immunohistochemical findings of four cases of primary esophageal carcinoid. The age of the patients ranged from 48 to 82 years (mean 63 years; median 61 years). The lower segment of the esophagus was involved in two cases and the mid segment was involved in one case. The sizes of the tumors ranged from 0.3 cm to 3.5 cm. Two tumors were confined to the lamina propria and two invaded into the muscular wall. Two tumors appeared polypoid, whereas the remaining two were incidental findings and associated with adenocarcinoma arising in a background of Barrett esophagus. The adenocarcinoma was superficially invasive in one case, whereas it penetrated the muscular wall in the other. All four carcinoid tumors were immunoreactive with chromogranin and synaptophysin. There was focal expression of serotonin in two cases, glucagon in one case, and pancreatic polypeptide in one case. Endocrine cell hyperplasia was noted in both the Barrett esophagus and the invasive adenocarcinoma. One patient died secondary to postoperative pneumonia. Three patients are alive and disease free at 1, 6, and 23 years status post therapy. None of the patients had metastatic disease. These findings show that esophageal carcinoids are associated with a favorable prognosis. They arise in two settings: (1) a single large polypoid tumor or (2) an incidental finding and in association with adenocarcinoma arising in the background of Barrett esophagus. The presence of endocrine cell hyperplasia in the Barrett mucosa and the adenocarcinoma supports the hypothesis that these lesions arise from a common stem cell.
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PMID:Carcinoid tumor of the esophagus: a clinicopathologic study of four cases. 1191 32