MTOR and leukemia: eIF4B has important roles in ABL-induced leukemia and in the pathogenesis of diffuse large B-cell lymphoma.38, 39, 40 In ABL-transformed leukemia cell line K562, eIF4B is activated and integrates the signals from the Pim and PI3K/Akt/mTOR pathway.39 In contrast, cells derived from eIF4B knockdown transgenic mice are less susceptible to ABL transformation.38 Similar to these observations, we found that silencing eIF4B by shRNA reduces the colony formation ability of K562 cells.