Background: Characterized by its highly aggressive tumor biology, pancreatic cancer still remains a fatal diagnosis. The junctional adhesion molecule A (JAM-A) is a type I transmembrane glycoprotein, which recently has been shown to affect the prognosis of several human malignancies.
Methods: JAM-A antigen expression was investigated retrospectively by immunohistochemistry in paraffin-embedded primary tumor tissue samples from a series (n = 186) of consecutive patients with pancreatic adenocarcinoma. Survival was calculated by Kaplan-Meier curves. Parameters found to be of prognostic significance in univariate analysis were verified in a multivariate Cox regression model.
Results: Low expression of JAM-A was observed in 79 (42 %) of 186 pancreatic cancer specimens and was significantly associated with poor overall survival (P < 0.01). By univariate analysis, low expression of JAM-A was found to correlate with positive lymph node status (P = 0.02), the presence of distant metastasis (P = 0.05), and tumor grade (P = 0.04), suggesting it may be an important event involved in cancer progression. Furthermore, in the subgroup of patients with surgically resected pancreatic cancer, low expression of JAM-A significantly correlated with decreased progression-free survival (P < 0.01). Multivariate analysis revealed JAM-A to be an independent predictor of poor outcome.
Discussion: These findings suggest for the first time that low levels of JAM-A expression in pancreatic cancer are associated with poor clinical outcome. JAM-A may represents a target molecule for functional inactivation and serve as a novel biomarker of adverse prognosis in pancreatic cancer.