USP2 and prostate cancer: Deubiquitinating enzyme, USP2a, an isoform of USP2, has been shown to have oncogenic properties in a variety of cancers through regulation of its substrate proteins, including MDM2, MDMX, FASN as well as Aurora A, and USP2a is abnormally over-expressed in multiple cancers, particularly in prostate cancer (Kim et al., 2012).