LncRNA expression profiles of 59 tumorous liver tissues derived from patients with hepatocellular carcinoma (HCC). Homo sapiens

Long noncoding RNAs (lncRNAs) are a class of non-coding RNAs longer than 200 nt that function in endogenous gene regulation and tumorigenesis. Hepatocellular carcinoma (HCC) is a heterogeneous disease with different treatment outcome. It is a challenge to develop a prognostic marker to identify HCC patients who are at greatest risk for recurrence or death. In this study, we try to screen lncRNAs whose expression levels are associated with recurrence or death of HCC patients through an extensive lncRNA profiling study on a cohort of 59 HCC patients. Overall design: For these experiments, we used RNA extracted from 59 HCC tissues and 20 normal livers. Total RNAs from the 20 normal livers were pooled and used as a reference for all microarray experiments. For each microarray experiment, Cy5-labeled probes derived from the DNase-treated total RNA from each HCC sample was hybridized against Cy3-labeled probes derived from common reference on Arraystar Human LncRNA Microarray (Arraystar, Rockville, USA). LncRNAs whose expression was significantly associated with disease-specific survival and time to recurrence were selected based on microarray data. The univariate Cox proportional hazards model was used to assess the association of lncRNAs with survival. We computed a statistical significance level (P value) for two endpoints—the time to cancer-related death and time to recurrence, based on univariate Cox proportional hazards models in BRB-ArrayTools version 4.2.0.