title: Claudin-4 expression is associated with tumor invasion, MMP-2 and MMP-9 expression in gastric cancer.
abstract: Claudin-4 is a member of the claudin family, a large family of transmembrane proteins that are essential in the formation and maintenance of tight junctions. Matrix metal-loproteinase (MMP)-2 and -9 degrade type IV collagen of the extracellular matrix and basal membranes. Claudin-4 activates MMP-2, indicating that claudin-mediated increased cancer cell invasion may result from the activation of MMP proteins. In the present study, we used immunohistochemistry to examine the expression levels of claudin-4, MMP-2 and MMP-9 in 189 gastric cancer samples, and analyzed their correlation with tumor invasion, clinicopathologic parameters and clinical outcome. The relationship between claudin-4 expression and MMP-2 and -9 expression was also investigated. The expression of claudin-4 was found to be significantly higher in gastric cancer cases with advanced depth of wall invasion, lymph node metastasis, lymphatic invasion and higher TNM stage. Further analysis revealed claudin-4 expression to be significantly correlated with the expression of MMP-2 and -9. Kaplan-Meier survival analysis indicated that MMP-9 expression was correlated with poor prognosis. These results suggest that claudin-4 expression is associated with tumor invasion and with MMP-2 and -9 expression in gastric cancer. Additionally, MMP-9 expression was demonstrated to serve as a prognostic factor in patients with gastric cancer.
authors.affiliation: Departments of Surgery, and.
authors.forename: Tsann-Long
authors.initials: TL
authors.lastname: Hwang
authors.forename: Li-Yu
authors.initials: LY
authors.lastname: Lee
authors.forename: Chee-Chan
authors.initials: CC
authors.lastname: Wang
authors.forename: Ying
authors.initials: Y
authors.lastname: Liang
authors.forename: Shu-Fang
authors.initials: SF
authors.lastname: Huang
authors.forename: Chi-Ming
authors.initials: CM
authors.lastname: Wu