Expression Pattern and Prognostic Significance of Claudin 1, 4 and 7 in Pancreatic Cancer

Background: Tight junctions (TJs) organise paracellular permeability and they have an important role inepithelial and endothelial cell polarity and permanence of barrier function. It has been demonstrated that theClaudin family constitutes an important component of them. In this study, we assessed expression patterns ofof Claudin1, 4 and 7 and whether they have any relation with prognosis in patients with pancreatic cancer.Materials and
Methods: Expression patterns of Claudin 1,4 and 7 were examined by immunohistochemistryin 25 patients with a histopathological diagnosis of pancreatic cancer using a semiquantitative scoring of theextent and intensity of staining. After grouping the staining scores as low (final score 0-2) and high (final score3-9) the relation between expression of Claudin 1,4 and 7 and survival was evaluated.
Results: There was nosignificant relation between expression of Claudin 1,4 and 7 and gender and stage. No statistically significantrelation was found between Claudin 1 and 4 expression and survival whereas a statistically significant relationwas found between decrease in Claudin 7 expression and decrease in survival.
Conclusions: Claudins haveimportant functions other than their popular function known as adhesion. Supporting this hypothesis, we founda statistically significant relationship between increased Claudin 7 expression and increased survival time, andthis suggests that Claudin 7 may exert different tumorigenic effects in pancreatic cancer other than its wellknownadhesion effect.