We found that the expression of circ_104075 was much higher in the serum of HCC patients compared to those of healthy individuals, and the average fold-change (circ_104075: 6.03 ± 2.99) was more obvious compared to other lncRNA and microRNA biomarkers (DANCR: 3.34 ± 2.20, HULC: 2.75 ± 1.92, UCA1: 2.34 ± 1.91, miR-21: 3.09 ± 2.26, and miR-223: 2.74 ± 1.90) (Fig. 1d). This evidence concerns the gene UCA1 and hepatocellular carcinoma.