Abstract: Abstract: USP22 is the ubiquitin-specific peptidase and a subunit of hSAGA complex subunit, belonging to the DUBs. Within hSAGA, USP22 deubiquitylates histone H2A and H2B and acetyltransfers H4 to regulate the transcription and expression of the related genes.Now that it is believed that USP22 is one of the death-from-cancer signature and associated with proliferation,invasion,metastasis and poor prognosis. It promotes the occurrence and development of tumor corresponding with the BMI-1，which is one of the Polycomb group, and Myc,FBP1 ,TRF1 .That makes it possible to become one of the tumor stem cell markers.

Key words: Keywords: USP22, death-from-cancer signature, tumor stem cell marker