MYSM1 and prostate cancer: Among these DUBs, MYSM1/Kiaa1915 (Myb-like SWIRM and MPN domain containing1, also 2A-DUB) was first functionally analyzed in prostate cancer cells, where it was shown to bind to double-stranded DNA and activate transcription of androgen receptor (AR) regulated genes by deubiquitinating H2A lysine 119 (H2A-K119ubi) [14].