Adenoviral E1A-associated protein p300 is involved in acute myeloid leukemia with t(11;22)(q23;q13)

p300, which was originally cloned as a nuclear binding target of the adenovirus E1A oncoprotein, forms a family with cyclic-AMP response element binding protein (CREB)-binding protein (CBP). p300/CBP are considered to be transcriptional coactivators that connect the basal transcriptional machinery to various DNA-binding transcriptional factors. p300/CBP are implicated in both cell differentiation and regulation of cell-cycle. We identify here that the p300 gene is fused to the MLL gene and that in-frame MLL-p300 fusion protein is generated in acute myeloid leukemia (AML) with t(11;22)(q23;q13). These finding suggest that the basis for the leukemogenesis of t(11;22)-AML is the inability of p300 to regulate cell-cycle end cell differentiation after fusion with MLL.