Also indicating a higher level of P-gp in resistant cells was the test with doxorubicin, which showed a lower intracellular accumulation of this compound in resistant than susceptible CML cells, as can be appreciated by the values of relative mean fluorescence intensity (RMFI) (Figure 1D). The gene discussed is PGP; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.