Dual drug-loaded PLA nanoparticles bypassing drug resistance for improved leukemia therapy

Abstract

Drug resistance is still a bottle-neck hindering successful chemotherapy in leukemia treatment. Nanocarriers have emerged as promising candidates to circumvent drug resistance and discover potent drug combinations. Here, we showed that co-encapsulation of daunorubicin (DNR) and glycyrrhizic acid (GA) in polylactic acid (PLA) nanoparticles effectively bypassed drug resistance and remarkably inhibited the growth of drug-resistant leukemia cells. The quantification of intracellular drug found that the encapsulation effectively increased drug uptake in the resistant K562/A02 cells. Modification of P-glycoprotein antibody on nanoparticles further enhanced drug accumulation in the leukemia cells, which was also confirmed by fluorescent microscopy imaging. More importantly, loaded in PLA nanoparticles, DNR and GA exerted an excellent synergistic effect, leading to significantly improved cell inhibition compared to the treatments without nanocarriers and those with a single drug. Correlative mechanism study revealed that the drug delivery system drastically enhanced cell apoptosis by regulating apoptotic genes but did not influence MDR1 expression. The present study proposes a versatile strategy to improve the therapeutic efficacy against drug-resistant leukemia and inspires the discovery of more potent drug combinations for enhanced leukemia therapy.