Camel Milk Exosomes Potentiate The Anticancer Effect of Doxorubicin on Multidrug-Resistant Human Leukemia Hl60 Cells in Vitro and in Vivo

Abstract

Background: Multidrug resistance (MDR) is one of the strategies developed by cancer cells to inhibit the anticancer potential of the majority of chemotherapeutic agents and almost results in treatment failure. Objective: This study aimed to evaluate the therapeutic potential of camel milk exosomes (CME) on multidrug-resistant human acute promyelocytic leukemia HL60 cells (HL60/RS) and to investigate whether this CME could potentiate the anticancer effect of Doxorubicin (DOX) and decrease its side effects. Results: CME alone or combined with DOX significantly induced HL60/RS cell viability loss, apoptosis, and cell cycle arrest at the G0/G1 phase, and downregulated MDR genes (Abcb1, Abcc1, Abcg2) as compared to cells treated with DOX alone. Additionally, CME and DOX co-treated nude mice had the lowest tumor volume, Abcb1, Abcc1, Abcg2, and Bcl2 expression, and the highest Bax and caspase3 expression in HL60/RS xenografts. This combined therapy also decreased DOX adverse effects as revealed by decreased liver damage enzymes and lipid peroxide (MDA) and increased hepatic antioxidant enzymes (SOD, CAT, GPx). Conclusion: CME increased sensitivity of HL60/RS to DOX through, at least in part, reduction of MDR genes, induction of apoptosis, and cell cycle arrest. Thus, CME may be used as safe adjuvants to DOX during cancer treatment. Keywords: Camel milk exosomes; Myeloid leukemia; HL60; Apoptosis; MDR