Accumulated evidence demonstrates cisplatin, a recommended chemotherapy, modulating pro-survival autophagic response that contributes to treatment failure in lung cancer patients. However, distinct mechanisms involved in cisplatin-induced autophagy in human lung cancer cells are still unclear. Herein, role of autophagy in cisplatin resistance was indicated by a decreased cell viability and increased apoptosis in lung cancer H460 cells pre-incubated with wortmannin, an autophagy inhibitor, prior to treatment with 50 µM cisplatin for 24 h. The elevated level of hydroxyl radicals detected via flow-cytometry corresponded to autophagic response, as evidenced by the formation of autophagosomes and autolysosomes in cisplatin-treated cells. Interestingly, apoptosis resistance, autophagosome formation, and the alteration of the autophagic markers, LC3-II/LC3-I and p62, as well as autophagy-regulating proteins Atg7 and Atg3, induced by cisplatin was abrogated by pretreatment of H460 cells with deferoxamine, a specific hydroxyl radical scavenger. The modulations in autophagic response were also indicated in the cells treated with hydroxyl radicals generated via Fenton reaction, and likewise inhibited by pretreatment with deferoxamine. In summary, the possible role of hydroxyl radicals as a key mediator in the autophagic response to cisplatin treatment, which was firstly revealed in this study would benefit for the further development of novel therapies for lung cancer.

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顺铂诱导的羟基自由基介导人肺癌 H460 细胞的促生存自噬

累积的证据表明，顺铂是一种推荐的化学疗法，可调节促生存自噬反应，导致肺癌患者治疗失败。然而，顺铂诱导人肺癌细胞自噬的不同机制仍不清楚。在本文中，自噬在顺铂耐药中的作用表现为在用 50 µM 顺铂处理 24 小时之前，与渥曼青霉素（一种自噬抑制剂）预孵育的肺癌 H460 细胞的细胞活力降低和细胞凋亡增加。通过流式细胞术检测到的羟基自由基水平升高对应于自噬反应，如顺铂处理细胞中自噬体和自体溶酶体的形成所证明的那样。有趣的是，细胞凋亡抗性、自噬体形成和自噬标志物的改变，顺铂诱导的 LC3-II/LC3-I 和 p62 以及自噬调节蛋白 Atg7 和 Atg3 通过用去铁胺（一种特定的羟基自由基清除剂）预处理 H460 细胞而被废除。在用通过芬顿反应产生的羟基自由基处理的细胞中也表明了自噬反应的调节，并且同样受到去铁胺预处理的抑制。总之，本研究首次揭示羟基自由基作为顺铂治疗自噬反应的关键介质的可能作用，将有利于肺癌新疗法的进一步开发。在用通过芬顿反应产生的羟基自由基处理的细胞中也表明了自噬反应的调节，并且同样受到去铁胺预处理的抑制。总之，本研究首次揭示羟基自由基作为顺铂治疗自噬反应的关键介质的可能作用，将有利于肺癌新疗法的进一步开发。在用通过芬顿反应产生的羟基自由基处理的细胞中也表明了自噬反应的调节，并且同样受到去铁胺预处理的抑制。总之，本研究首次揭示羟基自由基作为顺铂治疗自噬反应的关键介质的可能作用，将有利于肺癌新疗法的进一步开发。