To address whether eIF4A regulates the LEF1 IRES in a CML model, we transiently transfected K562 cells with the pSTF-LEF1 and β-gal reporters and treated the cells with increasing concentrations of hippuristanol (figure 3a,b, blue bars). Here, LEF1 is linked to chronic myelogenous leukemia, BCR-ABL1 positive.