SIRT1 and cancer: Ubiquitin‐specific protease 22 (USP22), a member of the deubiquitination module of the SAGA chromatin‐modifying complex, plays an important role in cancer stemness via various mechanisms.[6] An increasing number of studies have focused on the role of USP22 in malignant tumors.[7] Our previous work revealed that USP22 was able to promote HCC stemness by a HIF1α/USP22 positive feedback loop and mediate multidrug resistance (MDR) by activating the SIRT1/AKT/MRP1 pathway.