Serum DJ-1 as a diagnostic marker and prognostic factor for pancreatic cancer

OBJECTIVE: DJ-1 is an oncoprotein secreted by cancer cells. Therefore, it might be a diagnostic or prognostic biomarker for pancreatic cancer (PC). METHODS: The study involved 47 patients with PC, 43 with chronic pancreatitis, and 40 healthy subjects. We assayed the serum level of DJ-1 and the conventional tumor marker carbohydrate antigen 19-9 (CA 19-9) to define the diagnostic and prognostic value of DJ-1 for PC. RESULTS: Serum DJ-1 level was elevated in patients with PC compared with those with chronic pancreatitis and healthy individuals. The area under the curve (AUC) of serum DJ-1 was higher than CA 19-9 (DJ-1 vs. CA19-9, 0.8735 +/- 0.0356 vs. 0.6647 +/- 0.0572 ng/mL), and an 87.5% sensitivity was reached with a combination of serum DJ-1 and CA19-9. No association of serum DJ-1 level with tumor node metastasis (TNM) classification or tumor resectability was found. However, after resection, the median serum DJ-1 level was decreased from 2.00 to 0.78 ng/mL. In addition, higher serum DJ-1 was correlated with shorter overall survival as analyzed by both Kaplan-Meier test (P = 0.018) and COX regression analysis (P = 0.013). The median overall survival time of PC patients with serum DJ-1 level greater than or equal to 2.06 ng/mL was 7.00 +/- 1.11 months, whereas that of patients with lower DJ-1 levels was 13.0 +/- 2.5 months. CONCLUSIONS: These findings indicate the potential clinical significance for serum DJ-1 level to be used for the diagnosis and prognosis prediction of patients with PC.