The observed reduction in cell viability and clonogenicity results from nilotinib inhibiting the PDGF-BB-mediated activation of PDGFR- α, PDGFR- β, AKT, and mTOR, which it effects at a concentration below the mean peak inhibitor concentration (4.27 μM) found in the serum of patients treated for CML [18]. Here, AKT1 is linked to chronic myelogenous leukemia, BCR-ABL1 positive.