EZH2 and retinoblastoma: Another important point inferred from this study is that the similar anticancer activity of SAH‐EZH2 and GSK126 in RB cells may indicate that EZH2 would exert its oncogenic function mainly in the context of PRC2 complex in RB although non‐PRC2 or catalytic activity‐independent functions of EZH2 have been reported in other malignancies (Xu et al., 2012; Yan et al., 2013).