To further explore the biological function of the USP7/PRC2 complex in cancer development and progression in vivo, A375 cells were infected with lentiviruses carrying Control shRNA, USP7 shRNA, EZH2 shRNA, USP7 shRNA and FOXO1 shRNA, or EZH2 shRNA and FOXO1 shRNA. The gene discussed is FOXO1; the disease is cancer.