Expression profile of altered long non-coding RNAs in patients with HBV-associated hepatocellular carcinoma

In China, hepatitis B virus (HBV) infection is the major cause of hepatocellular carcinoma (HCC), which is called HBV-related HCC (HBV-HCC), but the pathogenesis has not been clearly elucidated. Long non-coding RNAs (lncRNAs) have been paid increasing attention to, as an important regulatory molecule involved in many biological processes, as well as a variety of diseases. This study examined lncRNA that might play an important role in HBV-HCC pathogenesis by conducting lncRNA and mRNA profile comparison between HBV-HCC and normal liver tissues. The differentially expressed lncRNA and mRNA profiles between HBV-HCC and normal liver tissues were analyzed by microarrays. The potential protein-encoding gene regulated by lncRNA, and the biological function (gene ontology, pathway analysis) of the target gene were investigated. The results showed that the expression levels of lncRNA and mRNA in HBV-HCC tissues were different from those in normal liver tissues. As compared with normal liver tissue, 837 (4.30%) lncRNAs exhibited more than two-fold change (P < 0.05); 325 were up-regulated, and 512 were down-regulated; 991 (5.70%) mRNAs exhibited more than 2-fold change (P < 0.05); 733 were up-regulated and 258 were down-regulated in HBV-HCC tissue. Besides, there were 7 lncRNAs with above 10-fold elevation, 6 lncRNAs with above 10-fold decrease, 18 mRNAs with above 10-fold elevation and 11 mRNAs with above 10-fold decrease. 444 (53.05%) lncRNAs had their corresponding mRNAs, some of which were adjacent to lncRNAs. The biological analysis showed that the target gene of differentially expressed lncRNAs took part in the important biological regulatory function. Target gene-related pathway analysis revealed the pathways in carcinoma and mitogen-activated protein kinase (MAPK) signaling pathways significantly changed in the HBV-HCC tissues as compared with normal liver tissues (P < 0.05). It was suggested that as compared with normal liver tissues, the expression of lncRNAs in HBV-HCC tissues changed significantly, and lncRNAs played a key role in the pathogenesis of HBV-HCC probably by mainly regulating the carcinoma-related signaling pathway and MAPK signaling pathways.