To test whether the high expression of PPFIA1 in CML is associated with therapeutic response, we analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay the IM sensitivity of K562 cells overexpressing PPFIA1 after treatment of cells with IM for 48 h. This evidence concerns the gene PPFIA1 and chronic myelogenous leukemia, BCR-ABL1 positive.