The knockdown efficiency of ZEB1 was shown in the Supplementary Fig. S2B. In addition, RNA-seq analysis for clinical HCC samples from GEPIA database also suggests that USP22 mRNA expression was positively correlated with those of ZEB1 downstream target genes, including MSRB3, MMP14 and VIM (vimentin) (Supplementary Fig. S2C). This evidence concerns the gene MMP14 and hepatocellular carcinoma.