Down-regulation of small nuclear RNA (snRNA) RNU5E-1 in hepatocellular carcinoma presents with vital clinical significance.

Abstract

For lack of accurate diagnosis and ideal prognosis assessment, hepatocellular carcinoma (HCC) has become the fourth cancers-related death malignant diseases. Small nuclear RNAs (snRNAs) have been investigated as a new class of regulators associated with pathogenesis and clinical evaluation of tumors such as HCC. As for RNU5E-1, one newly identified snRNA, may have similar functions. However, the relationship between RNU5E-1 expression and HCC tumorigenesis remains unclear. The relative RNU5E-1 expression was measured in several HCC cell lines and HCC tissues of 100 patients using quantitative real-time PCR. All patients were grouped according to individual RNU5E-1 expression. Then, the potential association between RNU5E-1 expression in HCC clinical characteristics and prognostic information of patients was evaluated. Compared to human normal hepatocyte cell line QSG-7701, the RNU5E-1 expression in HCC cell lines (fold change: SK-HEP-1, 0.417; Hep 3B, 0.313; Huh-7, 0.189) were significantly down-regulated (P<0.05). Similarly, its expression levels were remarkably lower in HCC tissue than that in corresponding adjacent liver tissues (average fold change: 0.322, P=0.002). Besides, the expression level of RNU5E-1 was remarkably related to tumor size, vessel carcinoma embolus, differentiation level, TNM stages and tumor recurrence rate as well as long-term survival in HCC patients (P<0.05). Moreover, in Kaplan-Meier and Cox regression analysis, RNU5E-1 expression was remarkably correlated to postoperative tumor-free as well as long-term survival in HCC patients as independent factors (P<0.05). The research revealed that RNU5E-1 was down-regulated in HCC and it could be one of indicators for diagnosis and prognostic prediction of HCC patients.