Interestingly, experiments in cancer cells indicated that KDM2B associates with a variant PRC1 complex containing BCoR (Bcl-6-interacting co-repressor), PCGF1 [polycomb group RING (really interesting new gene) finger 1], RYBP [RING and YY1 (Yin and Yang 1)-binding protein], YAF2 (YY1-associated factor 2) and RING1B [37–39]. This evidence concerns the gene YAF2 and cancer.