Prognostic Significance of Autophagy-Related Protein Expression in Resected Pancreatic Ductal Adenocarcinoma

OBJECTIVES: Autophagy is a critical intracellular pathway for the removal of aggregated proteins and damaged organelles. The aim of this study was to explore the contribution of autophagy-related proteins to clinical outcomes of patients with resected pancreatic ductal adenocarcinoma (PDAC). METHODS: The expression of 5 autophagy-related proteins in the PDAC tissues of 73 patients was evaluated by immunohistochemistry using a tissue array method. In addition, clinicopathological characteristics and survival were compared with the expression of autophagy-related proteins. RESULTS: Of the 73 patients, autophagy-related protein expression frequencies were 49.3% (36/73) for Atg5, 63.9% (46/72) for Ambra1, 47.9% (35/73) for beclin-1, 83.3% (60/72) for LC3B, and 69.9% (51/73) for Bif-1. The correlation between the expressions of autophagy-related proteins was significant for all protein pairs. Advanced T stage was marginally associated with a higher number of protein changes (P = 0.059). Multivariate analysis revealed that beclin-1 overexpression and increases in the alteration of autophagy-related proteins were independently associated with poor prognosis (hazard ratio of 5.365, P = 0.001 and hazard ratio of 5.270, P = 0.022, respectively). CONCLUSIONS: The acquisition of autophagy-related proteins is associated with poor clinical outcome in PDAC. The detection and inhibition of autophagy offers a potential therapeutic target for PDAC.