BAP1 and nonpapillary renal cell carcinoma: In addition, KLF5 can be stabilized by the deubiquitinase (DUB) BAP1,45 and BAP1 gene is inactivated in 15% ccRCC and defines a new class of ccRCC.46 Inactivation of deubiquitinases and over-activation of E3 ligases might be post-translational mechanism for the suppression of KLF5 in ccRCC.