BCL6 and lymphoma: On the other hand, the activated B-cell-like (ABC) subtype is typically negative for CD10 and BCL-6 but positive for MUM1, MYC, BCL2, and BCL6 rearrangements, particularly double-hit or triple-hit lymphomas (with concurrent MYC and BCL2 or BCL6 translocations), are associated with poor prognosis and may require more aggressive treatment.