ABCG2 and cancer: The purpose of this study was to evaluate the effect of ABCG2 monoclonal antibody (McAb) combined with paclitaxel (PTX) conjugated with Fe3O4 nanoparticles (NPs) on MM progressed from cancer stem cells (CSCs)in non-obese-diabetic/severe-combined-immunodeficiency (NOD/SCID) mouse model.