The results showed that, overexpression of USP22 significantly promoted the growth of HCC, and knockdown of ZEB1 inhibited the effect of USP22 on tumor growth (Fig. 6G–J), suggesting that ZEB1 was involved in the development of HCC, and the promotion of HCC growth by USP22 was partially related to ZEB1. This evidence concerns the gene ZEB1 and hepatocellular carcinoma.