In contrast, equivalent experiments investigating the effect of ABCC6 inhibition on imatinib efficacy in CML patient MNCs demonstrated no change in IC50IM in the absence or presence of ABCC6 inhibition (Fig 5B, S5B Fig): IC50IM in the absence of inhibitor = 0.96 μM versus 1 μM, 1 μM and 1.1 μM (p>0.05) in the presence of pantoprazole, indomethacin and probenecid respectively. This evidence concerns the gene ABCC6 and chronic myelogenous leukemia, BCR-ABL1 positive.