Effects of Y Box Binding Protein-1 in Progression and Prognosis of Cholangiocarcinoma.

Background and Objective: The preferred treatment for Cholangiocarcinoma (CCA) patients is surgery. Approximately, 35% of patients can undergo surgical resection in clinic. Biomarkers for CCA need to be identified for diagnosis, treatment, or prognosis prediction of this disease. Y-box binding protein-1 (YBOX-1) is highly correlated with tumor progression and poor overall survival in many malignancies. The prognostic value of YBOX-1 overexpression in CCA remains unclear. We examined the expression of YBOX-1 in resected tissue in CCA patients and studied the effect of YBOX-1 in CCA migration and invasion in vitro and in vivo. Methods: Expression of YBOX-1 in the tissue of 91 CCA patients was investigated by immunohistochemistry. The effects of YBOX-1 on migration, invasion, and proliferation in CCA cell lines were assessed by short hairpin RNA lentivirus or overexpression plasmid transfection. Results: A total of 55 (60.4%) of CCA cancerous tissues showed strongly positive YBOX-1 cytoplasmic staining. The strongly positive expression of YBOX-1 was close to early recurrence and poor overall survival by Kaplan-Meier analyses. Knockdown of YBOX-1 reduced migration and invasion in CCA cells and proliferation of tumor in xenotransplantation nude mice. Overexpression of YBOX-1 promoted migration and invasion in CCA cells and proliferation of tumor in xenotransplantation nude mice. Conclusion: YBOX-1 is correlated with early recurrence and poor overall survival in CCA. YBOX-1 may be a factor of predicting poor prognosis and overall survival.