In this study, we explored the cytotoxic effects of dBET1 on several AML cell lines (i.e., NB4, Kasumi, THP-1, and MV4-11), representing different molecular subtypes (i.e., PML-RARa, AML1-ETO, MLL-AF4, and MLL-AF9, respectively) of AML. Here, AFF1 is linked to acute myeloid leukemia.