Expression of TMPRSS4 in patients with salivary adenoid cystic carcinoma: correlation with clinicopathological features and prognosis

Although there is growing evidence supporting the hypothesis that TMPRSS4 is linked with cancer susceptibility, the precise role of TMPRSS4 expression in salivary adenoid cystic carcinoma (SACC) is still unknown. The aim of this study was to examine TMPRSS4 expression in SACC and determine its associations with clinicopathological features and survival. TMPRSS4 expression in 125 SACC tissue and adjacent non-cancerous tissues was analyzed by immunohistochemistry and Western blotting. In addition, the correlation of TMPRSS4 expression with clinicopathological variables was evaluated. The prognostic value of TMPRSS4 for overall survival (OS) and disease-free survival (DFS) was determined by Kaplan-Meier estimates, and the significance of differences between curves was evaluated by the log-rank test. We found that high TMPRSS4 expression was predominantly observed in SACC tissues, but not in the adjacent normal salivary gland tissues. High TMPRSS4 expression in SACC tissues was correlated significantly with tumor TNM stage (P = 0.016), lymph node metastasis (P = 0.002) and distant metastasis (P < 0.001). While high TMPRSS4 expression was associated with poor OS (P = 0.019) and DFS (P = 0.031), Cox regression analysis also revealed that TMPRSS4 was an independent predictor of OS and DFS. These findings suggested that TMPRSS4 was involved in the pathogenesis of SACC and might indicate a poor prognosis for SACC patients.