Elevated Expression Of Pmepa1 Predicts Poor Prognosis In Pancreatic Ductal Adenocarcinoma

Prostate transmembrane protein, androgen induced 1 (PMEPA1) has been reported to be upregulated and involved in the progression in multiple types of cancer. However, expression of PMEPA1 and its clinical significance in pancreatic ductal adenocarcinoma (PDAC) remain unclear. In this study, we measured the expression of PMEPA1 mRNA using qRT-PCR in 15 pairs of resected PDAC tissues and corresponding adjacent non-tumor tissues. In addition, we assessed the expression of PMEPA1 protein using immunohistochemistry in tissue microarray (TMA) which contains 74 pairs of PDAC tissues and corresponding adjacent non-tumor tissues, as well as another 18 PDAC tissues. Our analysis revealed that expression of PMEPA1 mRNA and protein were elevated in PDAC tissues compared with corresponding non-tumor pancreatic tissues (P< 0.001). High PMEPA1 expression was positively correlated with histological grade (P = 0.033) and regional lymph node metastasis (P = 0.015). Survival analysis showed that overall survival of patients with high PMEPA1 expression is significantly shorter than that of patients with low PMEPA1 expression (median survival 7.7 vs. 23 months, x(2) = 6.979, P = 0.008). The multivariate analysis indicated that high PMEPA1 expression was an independent prognostic factors for poor overall survival in PDAC (hazard ratio = 1.956, P = 0.015). High T stage (hazard ratio = 2.491, P = 0.001) and regional lymph node metastasis (hazard ratio = 2.245, P = 0.002) were also independent prognostic factors for poor survival in PDAC. In conclusion, PMEPA1 might be a valuable prognostic biomarker in PDAC and helpful to selecting patients who need adjuvant treatment.