pancreastatin and Stomach-Neoplasms

The role of enterochromaffin-like (ECL) cells in gastric carcinogenesis is not fully understood. Spontaneous tumours developing in hypergastrinemic female cotton rats have an adenocarcinoma phenotype, but numerous cells in the dysplastic mucosa as well as in the carcinomas are positive for neuroendocrine markers. In the present study of female cotton rats with 2 and 8 months' hypergastrinemia, the oxyntic mucosa of the stomach was examined histologically and immunolabelled for histidine decarboxylase (HDC) and pancreastatin, and hyperplastic and neoplastic ECL cells were evaluated by electron microscopy. These animals developed hyperplasia of the oxyntic mucosa in general and of the ECL cells in particular after 2 months and dysplasia and carcinomas after 8 months. The immunoreactivity of the ECL cells in the oxyntic mucosa was increased at 2 months and declined at 8 months. These histological changes were associated with progressive loss of secretory vesicles and granules in ECL cells. We suggest that ECL cells in hypergastrinemic cotton rats dedifferentiate with time and that the gastric carcinomas may develop from ECL cells.

Topics: Animals; Carcinoma; Cell Transformation, Neoplastic; Chromogranin A; Enterochromaffin-like Cells; Female; Gastrins; Histidine Decarboxylase; Hyperplasia; Pancreatic Hormones; Parietal Cells, Gastric; Rats; Sigmodontinae; Stomach Neoplasms

During recent years, gastric ECL cells have attracted much attention, mainly due to the fact that mice and rats were found to develop gastric carcinoids following lifelong treatment with blockers of acid secretion. We present the structure and functions of ECL cells and their influence on physiology and pathology of stomach and duodenum. We describe interactions of enzymes and hormones in histamine-stimulated gastric output.

Topics: Animals; Anti-Ulcer Agents; Chromogranin A; Duodenal Neoplasms; Duodenal Ulcer; Enterochromaffin-like Cells; Gastrins; Histamine; Mice; Pancreatic Hormones; Rats; Stomach Neoplasms; Stomach Ulcer

Distinguishing between neuroendocrine carcinoma and adenocarcinoma may be difficult.. In the current prospective study blood and tumor tissue from patients with gastric carcinoma were collected. The tissue was fixed in different ways to allow examination for neuroendocrine markers by multiple methods such as various histochemical and immunohistochemical methods and electron microscopy. Blood and tumor homogenates were examined by radioimmunoassay for specific hormones and general neuroendocrine markers.. Based on examination of general neuroendocrine markers such as chromogranin A (by immunohistochemistry, Northern blot analysis, and tissue concentration), neuron specific enolase (immunohistochemistry) as well as electron microscopy, it was possible to conclude that approximately 10% of the tumors were actually neuroendocrine malignant tumors. Among these tumors, the enterochromaffin-like (ECL) cell was the most preponderant cell of origin (Sevier-Munger positive and serotonin negative immunoreactive tumor cells with secretory granules resembling those observed in normal ECL-cells). As reported previously, tumors of the diffuse type (according to the classification of Laurén) most often were reclassified as neuroendocrine carcinomas.. The current study shows that neuroendocrine and particularly ECL cell-derived tumors are more common in the stomach than previously recognized.

Topics: Adenocarcinoma; Adult; Aged; Aged, 80 and over; Chromogranin A; Chromogranins; Enterochromaffin Cells; Female; Gastrins; Histamine; Humans; Immunohistochemistry; Male; Middle Aged; Neuroendocrine Tumors; Pancreatic Hormones; Prospective Studies; RNA, Messenger; Stomach Neoplasms