Long non-coding RNAs as targets for immunosuppressive drug teriflunomide in anti-cancer potential for hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is the most common form of liver cancer. Because of the relatively chemotherapy-refractory nature of HCC and significant potential poor hepatic reserve, chemotherapy has not been used consistently in the treatment of HCC. Effective new drugs for HCC are urgently needed. Teriflunomide, which was approved for the treatment of relapsing forms of multiple sclerosis (MS), has been identified as a potential antineoplastic drug. Long noncoding RNAs (lncRNAs) are a novel class of RNA molecules defined as transcripts longer than 200 nucleotides that lack protein coding potential. In this study, we investigated the ability of teriflunomide to act as an antineoplastic drug by examining the effects of teriflunomide treatment on HCC cells. Teriflunomide strongly inhibited the proliferation of HCC cells, induced cell apoptosis and induced cell accumulation in S phases of the cell cycle. LncRNA and mRNA expression profiles of HCC cells treated with teriflunomide compared with controls were performed by using microarray analysis. For comparison, the differentially expressed mRNAs were annotated by using gene ontology (GO) and pathway analyses. The microarray revealed that 2085 lncRNAs and 1561 mRNAs differed in the cells treated with teriflunomide compared with controls. Several GO terms including protein folding, mitochondrial outer membrane, transmembrane receptor protein phosphatase activity, negative regulation of cellular biosynthetic process, DNA packaging complex, and receptor signaling protein activity were enriched in gene lists, suggesting a potential correlation with the action mechanism of teriflunomide. Pathway analysis then demonstrated that JAK-STAT signaling pathway may play important roles in the cell apoptosis induced by teriflunomide. Co-expression network analysis indicated that a number of lncRNAs and mRNAs were included in the co-expression network, and p34710_v4 is the lncRNA with highest degree. Then the mRNAs associated with those differentially expressed lncRNAs were also annotated by using gene ontology (GO) and pathway analyses. The pathway analyses shows that teriflunomide significantly inhibited cell proliferation and promoted cell apoptosis partly by participating in Wnt signaling pathways. These findings suggest that teriflunomide could be a potential drug for chemotherapy and molecularly targeted therapies of HCC.