microRNAs (miRNAs) play key regulatory roles in various biological processes. In this study, we aimed to determine the expression and biological roles of miR-613 in hepatocellular carcinoma (HCC). Compared with non-cancerous liver tissues, miR-613 was significantly downregulated in HCC tissues. Ectopic expression of miR-613 significantly suppressed the proliferation and invasion of Hep3B and SMMC-7721 HCC cells. Bioinformatic and luciferase reporter analysis identified doublecortin-like kinase 1 (DCLK1) as a direct target of miR-613. Overexpression of miR-613 inhibited the expression of DCLK1 in HCC cells. There was a significant inverse correlation between miR-613 and DCLK1 protein expression in HCC samples. Small interfering RNA-mediated silencing of DCLK1 phenocopied the suppressive effects of miR-613 in HCC cells. Rescue experiments demonstrated that co-transfection of DCLK1 lacking the 3'-untranslated region partially prevented miR-613-induced suppression of HCC cell proliferation and invasion. In vivo studies confirmed that miR-613 overexpression retarded the growth of Hep3B xenograft tumors in nude mice, coupled with a reduction in the percentage of Ki67-positive tumor cells and DCLK1 protein expression. In conclusion, we provide first evidence for the suppressive activity of miR-613 in HCC, which is causally linked to targeting of DCLK1. Restoration of miR-613 may provide a potential therapeutic strategy for HCC. (C) 2016 Elsevier Inc. All rights reserved.