To investigate the expression of RNA binding motif protein 5 (RBM5) and its effect on clinical prognosis of hepatocellular carcinoma (HCC) patients after hepatectomy.

Clinical data of 241 patients with HCC who underwent hepatectomy in Eastern Hepatobiliary Surgery Hospital of the Second Military Medical University from January 2007 to January 2009 were retrospectively analyzed. Among them, 209 patients were male and 32 female, aged from 29 to 72 years with a median of 52 years. The informed consents of all patients were obtained and the local ethical committee approval was received. All patients were divided into the high-expression group (n=101) and low-expression group (n=140) according to the optimal cut-off value of RBM5 expression level. The expression level of RBM5 in HCC was analyzed using t test. Survival analysis was performed by Kaplan-Meier method and Log-rank test. The risk factors for prognosis of HCC patients were identified by Cox's proportional hazard regression model.

The mean optical density of RBM5 expression in HCC was 16±7, significantly higher than 13±7 in para-carcinoma (t=2.372, P<0.05). In low-expression group, the postoperative 3-, 5-year overall survival rates were 60%, 57%, and the postoperative 3-, 5-year tumor-free survival rates were 48%, 42%, respectively, and were 48%, 40%, and 33%, 27% correspondingly in high-expression group. The postoperative overall survival and tumor-free survival in low-expression group were significantly better than those in high-expression group (χ2=5.548, 6.035; P<0.05). Cox's multivariate analysis indicated that high expression of RBM5 was an independent risk factor for the overall survival and tumor recurrence of HCC patients after hepatectomy (HR=1.853, 1.650; P<0.05).

RBM5 is highly expressed in HCC patients, which is an independent risk factor for overall survival and tumor recurrence of HCC patients after hepatectomy. The overall prognosis of patients with low expression of RBM5 is better than patients with high expression of RBM5.