RARA and acute promyelocytic leukemia: The anti-proliferative effects of BEZ and MPA on a panel of cell lines representing diverse forms of AML including U937, NB4 (PML:RARα+ve APL), HL-60, K562 (BCR:ABL+ve AML blast crisis of chronic myeloid leukaemia) and KG1a cells are shown in Figure 1C and Figure S1.