BCL11B and leukemia: Importantly, BCL11B rearrangements (BCL11B-TLX3) in this subgroup are mechanistically distinct from those identified in BCL11B-rearranged lineage ambiguous leukemias, in that in the BCL11B-TLX3 leukemia, the BCL11B enhancer is used for aberrant expression of TLX3 at the cost of the loss of expression of BCL11B, leading to complete difference in expression profiles [5,146,147].