EIF2A and chronic myelogenous leukemia, BCR-ABL1 positive: In order to study the effect of eIF2α-P on the composition of CML secretome, we performed quantitative proteomics on media conditioned by K562 CML cells expressing GFP (K562wt) or a non-phosphorylable mutant of eIF2α (K562mut), which acts as a dominant negative protein and prevents the phosphorylation of endogenous eIF2α [22].