Owing to miR-216b expression, rather than other 6 predicted miRNAs, having a significant increase in siUCA1 treated HCC cells (Supplementary Figure S1), and an inverse correlation being further observed between UCA1 expression and miR-216b expression in HCC tissues and cell lines (Figure 4D–4F), we subsequently supposed that UCA1 might interact with miR-216b, serving as a potent natural miRNA sponge. The gene discussed is UCA1; the disease is hepatocellular carcinoma.