title: Expression of claudin-5 in canine pancreatic acinar cell carcinoma - An immunohistochemical study.
abstract: Claudin-5 is an endothelium-specific tight junction protein. The aim of the present study was to detect the expression pattern of this molecule in intact pancreatic tissues and in well-differentiated and poorly differentiated pancreatic acinar cell carcinomas from dogs by the use of cross-reactive humanised anticlaudin-5 antibody. The necropsy samples taken from dogs included 10 nonneoplastic pancreatic tissues, 10 well-differentiated pancreatic acinar cell carcinomas, 10 poorly differentiated pancreatic acinar cell carcinomas, 5 intrahepatic metastases of well-differentiated and 5 intrahepatic metastases of poorly differentiated acinar cell carcinomas. A strong lateral membrane claudin-5 positivity was detected in exocrine cells in all intact pancreas samples. The endocrine cells of the islets of Langerhans and the epithelial cells of the ducts were negative for claudin-5. The endothelial cells of vessels and lymphatic channels in the stroma of the intact pancreas showed strong membrane positivity for this claudin. All well-differentiated exocrine pancreas carcinomas and all poorly-differentiated pancreatic acinar cell carcinoma samples showed a diffuse loss of claudin-5 expression. The claudin-5-positive peritumoural vessels and lymphatic channels facilitated the detection of vascular invasion of the claudin-5-negative cancer cells. In liver metastasis samples, the pancreatic carcinomas were negative for claudin-5. It seems that the loss of expression of claudin-5 may lead to carcinogenesis in canine exocrine pancreatic cells.
authors.affiliation: Department of Pathology and Forensic Veterinary Medicine, Szent István University, István, Budapest, Hungary. Jakab.Csaba@aotk.szie.hu
authors.forename: Csaba
authors.initials: C
authors.lastname: Jakab
authors.forename: Miklós
authors.initials: M
authors.lastname: Rusvai
authors.forename: Péter
authors.initials: P
authors.lastname: Gálfi
authors.forename: Judit
authors.initials: J
authors.lastname: Halász
authors.forename: Janina
authors.initials: J
authors.lastname: Kulka
mesh_terms: D000818:Animals; D018267:Carcinoma, Acinar Cell / Q000378:metabolism / Q000662:veterinary*; D057167:Claudins / Q000235:genetics / Q000378:metabolism*; D004283:Dog Diseases / Q000378:metabolism*; D004285:Dogs; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology*; D007150:Immunohistochemistry / Q000662:veterinary; D010190:Pancreatic Neoplasms / Q000378:metabolism / Q000662:veterinary*
chemical_list: D057167:Claudins