 The NUP98-TOP1 fusion gene is one of 18 distinct translocations identified in acute myeloid leukemia involving the N-terminal portion of the nucleoporin NUP98.     ///    These results reveal the novel finding of collaboration between the ICSBP tumor suppressor gene and NUP98-TOP1 in leukemogenesis.     ///    "However, the long latency suggests the in vivo acquisition of additional mutations and/or time required for clonal outgrowth of rare transformed cells arising from the collaboration of NUP98-TOP1 and a cooperating event. "    ///    The in vivo myeloproliferation induced by NUP98-TOP1 was markedly exaggerated with the ICSBP(-/-) deficiency.     ///    "To ascertain whether an ISCBP deficiency collaborates with NUP98-TOP1 in leukemogenesis, we expressed NUP98-TOP1 in ICSBP(-/-) bone marrow. "    ///    "Moreover, NUP98-TOP1/ICSBP(-/-) mice had a reduced survival compared with NUP98-TOP1/ICSBP(+/+) mice. "