Long noncoding RNA RUSC1-AS-N indicates poor prognosis and increases cell viability in hepatocellular carcinoma.

OBJECTIVE: This study aimed at exploring the expression and prognostic values of a novel long noncoding RNA RUSC1-AS-N in hepatocellular carcinoma (HCC), and to investigate the biological roles of RUSC1-AS-N in HCC cells. PATIENTS AND METHODS: RUSC1-AS-N expression in public available microarray data was analyzed. The expression of RUSC1-AS-N in our cohort containing 66 HCC tissues and paired adjacent non-cancerous hepatic tissues was measured by qRT-PCR. The correlation between RUSC1-AS-N expression and clinicopathological characteristics was evaluated by Pearson χ2-test. The prognostic value of RUSC1-AS-N was analyzed by Kaplan-Meier survival analysis. The biological roles of RUSC1-AS-N on HCC cell viability were evaluated by Glo cell viability assays and Ethynyl deoxyuridine incorporation assays. The effects of RUSC1-AS-N on HCC cell cycle were evaluated by fluorescence-activated cell sorting (FACS) analyses of propidium-iodide (PI) stained cells. The effects of RUSC1-AS-N on HCC cell apoptosis were evaluated by TdT-mediated dUTP nick end-labeling (TUNEL) assays. RESULTS: RUSC1-AS-N is upregulated in HCC tissues and associated with poor prognosis of HCC patients from GSE54238 and GSE40144. In our cohort, we further confirmed the upregulation of RUSC1-AS-N in HCC tissues. High expression of RUSC1-AS-N associates with large tumor size, vein invasion, encapsulation incompletion, advanced BCLC stage, and poor recurrence-free survival and overall survival. Functional assays revealed that RUSC1-AS-N knockdown markedly decreases cell viability, induces cell-cycle arrest and apoptosis of HCC cells. CONCLUSIONS: RUSC1-AS-N is upregulated and acts as an oncogene in HCC. RUSC1-AS-N may be a promising prognostic biomarker and therapeutic target for HCC.