USP7 (ubiquitin-specific protease 7) is able to interact with LSD1, exercising deubiquitination functions and enhancing the inhibitory effect of LSD1 on p53 (tumor protein p53).42, 43, 44 Phosphorylation of LSD1 catalyzed by GSK3β promotes the binding of LSD1 to USP22 (ubiquitin specific protease 22), and deubiquitination of LSD1 promotes tumor formation.29 This evidence concerns the gene TP53 and neoplasm.