MCL1 and acute myeloid leukemia: Additionally, AML cell lines with MLLr/MLL-PTD lost HOXA9 after treatment with fadraciclib, which may also contribute to proliferation suppression.105 For tumors not dependent on the depletion of MCL-1, including some AML cell lines HEL, THP-1, and PL21, ABT-263/ABT-737, or venetoclax (BCL2 inhibitor) in combination with fadraciclib was effective at inducing apoptosis.105