High Expression of Y-Box-Binding Protein-1 is Associated with Poor Survival in Resectable Esophageal Squamous Cell Carcinoma

Abstract

Y-box-binding protein-1 (YB-1) is a multifunctional protein that regulates gene expression through both transcriptional and translational mechanism. Its expression has been associated with tumor progression and poor prognosis of many cancers. However, its role and clinical significance in resectable esophageal squamous cell carcinoma (ESCC) is still scanty. The purpose of this study was to investigate the prognostic significance of YB-1 expression by immunohistochemistry in a group of patients with ESCC treated with surgical resection. Tissue microarray that included 233 surgically resected ESCC specimens and 49 cases of adjacent normal tissues was successfully generated for immunohistochemical evaluation. The clinical/prognostic significance of YB-1 expression was statistically analyzed. Kaplan-Meier analysis was used to compare the postoperative survival between groups. The results showed the immunostaining of YB-1 was distributed predominantly in cytoplasm in tumor cells, which occurred in all of the 233 patients. A higher recurrence (disease-free survival) and lower survival (overall survival) of ESCC was found in patients whose tissues had increased YB-1 expression (P<.001/P=.001). Furthermore, YB-1 expression could stratify the patient survival (disease-free survival/overall survival) in stage II (P=.012/.016). The Cox proportionate hazard regression model also established that high YB-1 expression was significantly correlated with increased risk (RR=1.752) of recurrence compared with lowYB-1 expression (P=.004). High expression of YB-1 is associated with poor survival in resectable ESCC patients.