NOVEL MLL-CBP FUSION TRANSCRIPT IN THERAPY-RELATED CHRONIC MYELOMONOCYTIC LEUKEMIA WITH A T(11-16) (Q23-P13) CHROMOSOME-TRANSLOCATION

CBP, which is located on 16p13 and encodes a transcriptional adaptor/c oactivator protein, has been shown to fuse by the t(8;16)(p11;p13) tra nslocation to MOZ on 8p11 in acute myeloid leukemia. We found a t(11;1 6)(q23;p13) in a child with therapy-related chronic myelomonocytic leu kemia. Subsequent reverse transcriptase-polymerase chain reaction and direct sequencing analyses revealed the MLL-CBP fusion transcript in C MML cells. Because 11q23 translocations involving MLL and t(8;16) invo lving MOZ and CBP have been reported in therapy-related leukemias, bot h the MLL and CBP genes may be targets for topoisomerase II inhibitors . Accordingly, we believe that most t(11;I6)-associated leukemias may develop in patients who have been treated with cytotoxic chemotherapy for primary malignant diseases. (C) 1997 Wiley-Liss, Inc.