Leukemia development was significantly delayed in USP7-inhibitor-treated mice, and in particular in two mice a clear response to USP7 inhibition was observed and chimerism levels remained relatively stable between day 56 and 67 post-transplant, although ultimately those mice also did develop MLL-AF9-induced leukemia after day 77 (Figure 8I). Here, MLLT3 is linked to leukemia.