EZH2 Y641F accelerates lymphoma development in combination with Eµ-Myc. (A) Kaplan-Meier survival analysis of EZH2^Y641F (n = 36), Eµ-Myc (n = 26), Eµ-Myc/EZH2^Y641F (n = 20), and WT control mice (n = 38) (P < .0001 log-rank [Mantel-Cox] test). Mice used for experiments and analyses at defined time points were censored at the time of analysis. (B) H&E staining of a lymph node from an Eµ-Myc/EZH2^Y641F at the time of death. (C) Wright-Giemsa stained blood smear at time of death. (D) H&E staining of liver from an Eµ-Myc/EZH2^Y641F at the time of death showing lymphoma infiltration of the liver. (E) Immunophenotypic analysis of bone marrow (BM) and peripheral blood (PB) samples from an Eµ-Myc/EZH2^Y641F lymphoma mouse at the time of death. (F) Southern blot analysis for clonality of IgH gene rearrangements for Eµ-Myc lymphomas (upper) and Eµ-Myc/EZH2^Y641F lymphomas (lower) was performed by probing EcoRI-digested genomic DNA with a JH4 probe. DNA samples used were from BM, spleen (Sp), and where available lymph node (LN).