We investigated expression of multidrug resistance genes MDR1, LRP and BCRP and antiapoptotic gene Bcl-2 in leukemic cells at diagnosis, and MRD level at the end of induction therapy, and could not find obvious relations between these parameters.
Nevertheless, an ABCG2 higher expression appeared associated with a worse PFS and levels of this gene paralleled the status of minimal residual disease.
Nevertheless, an ABCG2 higher expression appeared associated with a worse PFS and levels of this gene paralleled the status of minimal residual disease.
Emergence of MRD is thus not accompanied by either upregulation of ABC-transporter function during or after chemotherapy or by selection of pre-existing highly resistant subpopulations.