title: Strong claudin 5 expression is a poor prognostic sign in pancreatic adenocarcinoma.
abstract: We investigated the expression of claudin 5 in 88 ductal adenocarcinomas of the pancreas. The results were correlated with patient prognosis, with claudin 5 expression in blood vessels, with the expression level of bcl2 and bax and with apoptosis. Claudin 5 expression was detected in 24 (38%) cases. It was not associated with tumour size or spread, but strong claudin 5 expression correlated with a worse survival (p = 0.005). Claudin 5 also associated with a higher extent of apoptosis and greater expression of bax protein. In the tumour vasculature, some vessels displayed a loss of claudin 5 expression. The presence of this loss was associated with tumour grade and the presence of nodal metastases (p = 0.02, p = 0.022, respectively). These results indicate that claudin 5 is upregulated in a proportion of pancreatic ductal adenocarcinomas. The association of strong claudin 5 expression with a worse survival is in line with some earlier reports indicating that this protein is involved with increased locomotion and more aggressive spread of carcinomas. The association of claudin 5 with apoptosis and bax might be due to stronger cellular kinetics found in such tumours. The loss of claudin 5 expression in the tumour vasculature points to a leaky vessel type; this might also ease the access of tumours to vessels and be reflected in its association with the presence of nodal metastases.
authors: Department of Pathology and Forensic Medicine, Institute of Clinical Medicine, Pathology and Forensic Medicine, School of Medicine, University of Eastern Finland, Cancer Center of Eastern Finland, Kuopio, Finland, ylermi.soini@uef.fi.
authors: Ylermi
authors: Y
authors: Soini
authors: M
authors: M
authors: Eskelinen
authors: P
authors: P
authors: Juvonen
authors: V
authors: V
authors: Kärjä
authors: K M
authors: KM
authors: Haapasaari
authors: A
authors: A
authors: Saarela
authors: P
authors: P
authors: Karihtala
mesh_terms: D000230:Adenocarcinoma / Q000098:blood supply / Q000401:mortality / Q000473:pathology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D021441:Carcinoma, Pancreatic Ductal / Q000098:blood supply / Q000401:mortality / Q000473:pathology*; D062507:Claudin-5 / Q000032:analysis / Q000502:physiology*; D058750:Epithelial-Mesenchymal Transition; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000098:blood supply / Q000401:mortality / Q000473:pathology*; D011379:Prognosis; D051028:bcl-2-Associated X Protein / Q000032:analysis
chemical_list: C494826:BAX protein, human; C107466:CLDN5 protein, human; D062507:Claudin-5; D051028:bcl-2-Associated X Protein