IκB Kinase ε Expression in Pancreatic Ductal Adenocarcinoma

I kappa B kinase (IKK epsilon) is a serine/threonine protein kinase that belongs to the IKK kinase family. Recent studies have shown that IKK epsilon functions as a breast and ovarian cancer oncogene. We demonstrated frequent overexpression of IKK epsilon in pancreatic ductal adenocarcinoma (PDA). We immunohistochemically evaluated 78 PDAs using the avidin-biotin-peroxidase method and the anti-IKK epsilon rabbit polyclonal antibody. Elevated IKK epsilon reactivity (immunohistochemical score, 4-9) was observed in 64% of PDAs (50/78), but in 0.0% of nonneoplastic pancreatic ductal epithelium (0/113; P < .001). Kaplan-Meier analysis of overall survival revealed that patients with high IKK epsilon-immunohistochemical scores (4-9) had significantly shorter survival than did patients with low IKK epsilon immunohistochemical scores (0-3; P = .023; log-rank test) independent of tumor stage or grade. These data indicate that deregulation of IKK epsilon is a common event in PDA and might have an important role in the pathogenesis of this deadly disease. In addition, IKK epsilon could serve as a prognostic marker and potential therapeutic target for PDA intervention.