ABCB1 and breast cancer: Novel polymer-lipid hybrid nanoparticle loaded with doxorubicin and chemosensitizer (GG918) evaluated in human MDR breast cancer cell line (MDA435/LCC6/MDR1) demonstrated nuclear drug localization and anticancer activity toward MDR cells, while co-administration of the single-agents loaded nanoparticles resulted in high cellular internalization but were ineffective (Wong et al., 2006).