Consistently with a BAP1/PR-DUB functional role in PcG-mediated repression in Drosophila (Scheuermann et al., 2010), the complex BAP1-associated transcriptional network in mammals includes expression programs regulated by PcG proteins (Bott et al., 2011; Dey et al., 2012; Peña-Llopis et al., 2012), the genetic alteration of which predisposes to the development of various cancers (Sparmann and van Lohuizen, 2006; Di Croce and Helin, 2013). This evidence concerns the gene BAP1 and cancer.