CAST and chronic myelogenous leukemia, BCR-ABL1 positive: We found IM treatment significantly increased apoptosis in CML-myeloid progenitors with Gas2 knockdown, with or without Fas-agonist (p < 0.001, n = 3), and in differentiating CML granulocytes with Calpastatin knockdown, with or without Fas-agonist (p < 0.01, n = 3) (Figure 5E).