The development of multidrug resistance (MDR) is a commonly observed phenomenon in many cancer types. It contributed significantly to the poor outcome of many currently available chemotherapies. Considering autophagy as one of the most important physiological process in cancer progression, we thereby proposed an anti-autophagy siRNA and doxorubicin (Dox) co-delivery system (MC/D-siR) to combat MDR breast cancer using sequential construction. Our results demonstrated the potential of MC/D-siR to effectively transfect the loaded siRNA to result in significant downregulation of intracellular autophagy level in MCF-7/Adr (Dox resistance MCF-7 cell line) cells, which in turn cut off the ATP supply and to reverse the MDR and potentiated accumulated drug retention in cells. As a result, MC/D-siR showed much elevated anticancer benefits than single loaded platforms (MC/Dox or MC/siRNA), indicating the ability for effective MDR cancer treatment through the combination of autophagy regulation and chemotherapy.

中文翻译：

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自噬调节和协同治疗使用混合细胞膜纳米颗粒对抗多药耐药性乳腺癌。

多药耐药 (MDR) 的发展是许多癌症类型中常见的现象。它对许多目前可用的化学疗法的不良结果产生了重大影响。考虑到自噬是癌症进展中最重要的生理过程之一，因此我们提出了一种抗自噬 siRNA 和多柔比星 (Dox) 共递送系统 (MC/D-siR)，以使用顺序构建来对抗 MDR 乳腺癌。我们的结果证明了 MC/D-siR 有效转染负载的 siRNA 的潜力，导致 MCF-7/Adr（Dox 抗性 MCF-7 细胞系）细胞的细胞内自噬水平显着下调，从而切断 ATP供应和逆转 MDR 并增强细胞中积累的药物保留。其结果，