In normal hepatocyte cell lines HL-7702, overexpression of USP3 did not have the function of stabilizing MDM2, and CO-IP experiments demonstrated that there was no interaction between them, indicating that the deubiquitination of MDM2 by USP3 only occurred in hepatoma cells and promoted the proliferation of HepG2 cells. This evidence concerns the gene USP3 and hepatocellular carcinoma.