Serum Exosomal EphA2 is a Prognostic Biomarker in Patients with Pancreatic Cancer

Background: Pancreatic cancer (PC) is one of the worst prognoses amongst all malignant diseases. It is therefore of great significance to identify biomarkers with predictive clinical value for the prognosis and recurrence of PC. Methods: In our study, enzyme-linked immunosorbent assays (ELISA) were used to detect the expression of Exo-EphA2 in the serum of PC patients and controls. Kaplan-Meier curve and Cox regression analyses were used to evaluate the prognostic value of Exo-EphA2 expression in patients with primary and recurrent PC. Results: The level of serum Exo-EphA2 was significantly higher in the PC group when compared to that of the control group. High expression of Exo-EphA2 in PC was associated with shorter overall survival (OS) and proved to be a significant negative prognostic factor in the multivariate analysis (HR = 1.04, 95% CI: 1.00-1.09, P <0.001). Additionally, we found that the level of serum Exo-EphA2 in recurrent PC patients (first recurrence < 12 months) was positively correlated with the level of Exo-EphA2 at primary diagnosis. Multivariate analysis showed that a high expression of Exo-EphA2 in recurrent PC was associated with shorter recurrence-free survival (RFS) (HR = 1.41, 95% CI: 1.10-1.70, P < 0.001). Conclusion: High expression of serum Exo-EphA2 represents a novel biomarker for a poor prognosis in PC patients.