N-wasp in pancreatic ductal adenocarcinoma: associations with perineural invasion and poor prognosis.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) has long been acknowledged to have a dismal prognosis. Therefore, prognostic markers, especially molecular ones, are of interest. So far, expression of Neural Wiskott-Aldrich syndrome protein (N-WASP) and its associations with clinicopathologic variables and prognosis for patients with PDAC remain unknown. METHODS: N-WASP expression was detected by immunohistochemical staining in a tissue microarray consisted of tumor and nontumor samples from 86 patients with PDAC. The correlations of N-WASP expression with clinicopathologic features and overall survival were evaluated. In addition, risk factors of perineural invasion (PNI) were identified. RESULTS: High expression of N-WASP was more frequent in tumor than in nontumor tissues of PDAC patients (45.3 vs. 19.8%, p < 0.001). The rank of N-WASP grading was significantly higher in tumor tissues than in nontumor tissues (p = 0.048). Also, high expression of N-WASP in tumor tissues was significantly associated with PNI, and lymph node status had a marginally significant relation to tumoral N-WASP expression. Univariate analyses showed that, in addition to conventional clinicopathologic variables, including sex, histologic grade, PNI and lymph node metastasis, high tumoral N-WASP expression was an independent marker of PNI and served as a significant predictor of poor overall survival. The prognostic implication of N-WASP expression was not proven In the multivariate analysis. CONCLUSIONS: Our data showed highly up-regulated expression of N-WASP in PDAC tissues, its correlations with PNI, and its association with an unfavorable prognosis.