MCL1 and acute myeloid leukemia: Cell viability was determined in AML cell lines treated with increasing dosages of single compounds and in combination treatments using the BMI-1 inhibitor PTC596 and a variety of targeted therapies including the TP53 activator APR-246 (Figure 3A), the MCL1 inhibitor S63845 (Figure 3B), and the MEK inhibitor trametinib (Figure 3C).