MTOR and acute myeloid leukemia: Consistently, simultaneous inhibition of the PI3K/mTOR pathway, by BEZ235, and Bcl-2/Bcl-xL, by ABT-737, strongly potentiated cytotoxicity of single agents and markedly reduced colony formation in multiple AML cell lines and primary blast specimens while exerted only modest toxicity toward normal hematopoietic progenitors [60].