Abstract: ObjectiveTo investigate the expression and clinical significance of ribosome-binding protein 1 (RRBP1) in esophageal carcinoma. MethodsA total of 120 esophageal carcinoma patients admitted to Yulin First Hospital of Shaanxi Province from January 2010 to December 2014 were enrolled in this study. RRBP1 expression was detected in esophageal carcinoma and matched adjacent normal tissues by real-time quantitative PCR (qRT-PCR), Western blotting and immunohistochemical staining. The relationships of RRBP1 expression with clinicopathological futures and prognosis were statistically analyzed. ResultsRRBP1 expression level was significantly higher in esophageal carcinoma tissues compared with matched adjacent normal tissues. In the mRNA level, the relative quantitative expression in tumor tissues was 3.5±1.3, and 1.0±0.3 in adjacent normal tissues, with a significant difference (t=19.130, P＜0.001). In the protein level, the relative quantitative expression in tumor tissues was 1.0±0.4, and 0.3±0.1 in adjacent normal tissues, with a significant difference (t=4.225, P＜0.001). The immunohistochemical results showed that RRBP1 high expression was found in 71 (59.2%) tumor tissues, and the proportion dropped to 11.7% (14/120) in adjacent normal tissues, with a significant difference (χ2=59.182, P＜0.001). In addition, RRBP1 expression was correlated with lymph node metastasis and TNM stage (χ2=10.631, P=0.001; χ2=31.212, P＜0.001). Survival analysis revealed that RRBP1 expression, lymph node metastasis and TNM stage were significantly correlated with patients′ prognosis (χ2=9.455, P=0.006; χ2=14.542, P＜0.001; χ2=11.987, P＜0.001). Cox regression analysis showed that high expression of RRBP1 (RR=2.441, 95%CI: 1.267-4.702, P=0.008), lymph node metastasis (RR=4.024, 95%CI: 2.180-7.424, P＜0.001) and high TNM stage (RR=3.054, 95%CI: 1.452-6.421, P=0.003) were the risk factors for poor prognosis of esophageal carcinoma patients. ConclusionRRBP1 is highly expressed in esophageal carcinoma and can serve as a potential biomarker to predict patients′ prognosis.

Key words: Esophageal neoplasms, Prognosis, Survival analysis, Ribosome-binding protein 1