The small-molecule inhibitor mediated disruption of the activity of BCL6, can be selectively toxic towards high-risk BCL6-dependent BCR-subtypes of GCB and ABC-DLBCL in vitro and potently suppressed GCB-DLBCL tumors in a DLBCL xenograft mouse model in vivo through reactivating pro-apoptotic genes repressed by BCL6 [123, 385, 386]. The gene discussed is BCL6; the disease is aneurysmal bone cyst.