To further validate whether HERC2 regulated HCC cells through STAT3 signaling, STAT3-deficient/HERC2 knockout Huh7 and STAT3-deficient/HERC2 overexpressing HCC-97 h cells were established by the CRISPR-Casp9 system (Fig. 5E and Supplementary Fig. S4A). Here, CASP9 is linked to hepatocellular carcinoma.