title: Gastric PDX-1 expression in pancreatic metaplasia and endocrine cell hyperplasia in atrophic corpus gastritis.
abstract: The homeodomain transcription factor PDX-1 plays a key role in endocrine and exocrine differentiation processes of the pancreas. PDX-1 is also essential for differentiation of endocrine cells in the gastric antrum. The role of PDX-1 in the pathogenesis of endocrine cell hyperplasia and pancreatic metaplasia in corpus and fundus gastritis has not been evaluated. By immunohistochemistry and double-immunofluorescence, we investigated the expression of PDX-1 in 10 tissue specimens with normal human gastric mucosa, nonatrophic and atrophic gastritis and in pancreatic metaplasia, respectively. In normal corpus mucosa and in nonatrophic corpus gastritis, PDX-1 was mainly absent. In pancreatic metaplasia, PDX-1 was found in metaplastic cells and in adjacent gastric glands. In contrast to normal gastric corpus mucosa, PDX-1 could be strongly detected in the cytoplasm of the parietal cells surrounding metaplastic areas. Furthermore, PDX-1 expression was found in hyperplastic endocrine cells and in the surrounding gastric glands in chronic atrophic gastritis. Hyperplastic endocrine cells coexpressed the beta-subunit of the gastric H,K-ATPase. We conclude that PDX-1 represents a candidate switch factor for glandular exocrine and endocrine transdifferentiation in chronic gastritis and that an impaired parietal cell differentiation might play a key role in disturbed gastric morphogenic processes.
authors: Institute of Pathology, University of Erlangen-Nuremberg, Erlangen, Germany.
authors: Maike
authors: M
authors: Buettner
authors: Arno
authors: A
authors: Dimmler
authors: Achim
authors: A
authors: Magener
authors: Thomas
authors: T
authors: Brabletz
authors: Manfred
authors: M
authors: Stolte
authors: Thomas
authors: T
authors: Kirchner
authors: Gerhard
authors: G
authors: Faller
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000032:analysis; D054338:Cell Transdifferentiation; D019858:Enteroendocrine Cells / Q000737:chemistry* / Q000201:enzymology / Q000473:pathology; D005260:Female; D005455:Fluorescent Antibody Technique; D005753:Gastric Mucosa / Q000737:chemistry; D005757:Gastritis, Atrophic / Q000201:enzymology / Q000378:metabolism* / Q000473:pathology; D018398:Homeodomain Proteins / Q000032:analysis*; D006801:Humans; D006965:Hyperplasia; D007150:Immunohistochemistry; D008297:Male; D008679:Metaplasia; D008875:Middle Aged; D010179:Pancreas / Q000737:chemistry* / Q000201:enzymology / Q000473:pathology; D011706:Pyloric Antrum / Q000737:chemistry; D000254:Sodium-Potassium-Exchanging ATPase / Q000032:analysis; D013270:Stomach / Q000737:chemistry* / Q000201:enzymology / Q000473:pathology; D015534:Trans-Activators / Q000032:analysis*; D015854:Up-Regulation
chemical_list: D015415:Biomarkers; D018398:Homeodomain Proteins; D015534:Trans-Activators; C084010:pancreatic and duodenal homeobox 1 protein; D000254:Sodium-Potassium-Exchanging ATPase