Prognostic significance of peroxiredoxin 1 and ezrin-radixin-moesin-binding phosphoprotein 50 in cholangiocarcinoma.

We performed a comparative proteomic analysis of protein expression profiles in 4 cholangiocarcinoma cell lines: K100, M156, M213, and M139. The H69 biliary cell line was used as a control. Peroxiredoxin 1 and ezrin-radixin-moesin-binding phosphoprotein 50 were selected for further validation by immunohistochemistry using a cholangiocarcinoma tissue microarray (n = 301) to assess their prognostic value in this cancer. Both peroxiredoxin 1 and ezrin-radixin-moesin-binding phosphoprotein 50 were overexpressed in cholangiocarcinoma tissues compared with normal liver tissues. Of the 301 cholangiocarcinoma cases, overexpression of peroxiredoxin 1 in 103 (34.3%) was associated with an age-related effect in young patients (P = .011) and the absence of cholangiocarcinoma in lymphatic vessels and perineural tissues (P = .004 and P = .037, respectively). Expression of radixin-moesin-binding phosphoprotein 50 correlated with histopathologic type, with 180 (59.8%) of moderately or poorly differentiated tumors (P = .039) being higher, and was associated with the presence of cholangiocarcinoma in lymphatic and vascular vessels (P < .001 and P < .001, respectively). The high expression of radixin-moesin-binding phosphoprotein 50 and the low expression of peroxiredoxin 1 correlated with reduced survival by univariate analysis (P = .017 and P = .048, respectively). Moreover, the impact of peroxiredoxin 1 and radixin-moesin-binding phosphoprotein 50 expression on patient survival was an independent predictor in multivariate analyses (P = .004 and P = .025, respectively). Therefore, altered expression of peroxiredoxin 1 and radixin-moesin-binding phosphoprotein 50 may be used as prognostic markers in cholangiocarcinoma.