EZH2 and cancer: The methyltransferase Ezh2 has pleiotropic effects during development and homeostasis and in pathological conditions such as cancer (Cao et al., 2002; Kuzmichev et al., 2002; Varambally et al., 2002; Kleer et al., 2003; Francis et al., 2004; Kamminga et al., 2006; Barski et al., 2007; Wagener et al., 2008; Ezhkova et al., 2009; Simon and Kingston, 2013).