Clinical responses of B-cell lymphomas to one of these inhibitors, Tazemetostat (Italiano et al., 2018), are not limited to cases with hypomorphic mutations of EZH2. This therefore suggests that the wild-type activity of EZH2 in GCB cells, and hence the activity of BCL6, may be an additional determinant of response to EZH2 inhibition. This evidence concerns the gene EZH2 and B-cell non-Hodgkin lymphoma.