Mitochondrial superoxide anions induced by exogenous oxidative stress determine tumor cell fate: an individual cell-based study  

外源性氧化应激诱导的线粒体超氧阴离子决定肿瘤细胞命运:一项基于单个细胞的研究（英文）

作　　者：Hui PAN Bao-hui WANG Zhou-bin LI Xing-guo GONG Yong QIN Yan JIANG Wei-li HAN 

机构地区：[1]The First Affiliated Hospital, College of Medicine, Zhejiang University [2]Zhejiang Hospital of Traditional Chinese Medicine, Zhejiang Chinese Medical University [3]Institute of Biochemistry, College of Life Sciences, Zhejiang University

出　　处：《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》2019年第4期310-321,共12页浙江大学学报（英文版）B辑（生物医学与生物技术）

基　　金：Project supported by the Zhejiang Provincial Natural Science Foundation of China(No.LY18H300002);the Medical Health Science and Technology Project of Zhejiang Provincial Health Commission(No.2019RC061/2019312897);the Zhejiang Provincial Natural Science Foundation of China(Nos.Y4110212 and LY19H090001);partly by the National Natural Science Foundation of China(Nos.81372301 and 81301113)

摘　　要：Objective: Reactive oxygen species(ROS) are involved in a variety of biological phenomena and serve both deleterious and beneficial roles. ROS quantification and assessment of reaction networks are desirable but difficult because of their short half-life and high reactivity. Here, we describe a pro-oxidative model in a single human lung carcinoma SPC-A-1 cell that was created by application of extracellular H2O2 stimuli. Methods: Modified microfluidics and imaging techniques were used to determine O2·- levels and construct an O2^·- reaction network. To elucidate the consequences of increased O2^·- input, the mitochondria were given a central role in the oxidative stress mode, by manipulating mitochondria-interrelated cytosolic Ca2+ levels, mitochondrial Ca^2+ uptake, auto-amplification of intracellular ROS and the intrinsic apoptotic pathway. Results and conclusions: Results from a modified microchip demonstrated that 1 mmol/L H·-2 O2 induced a rapid increase in cellular O2 levels(>27 vs.>406 amol in 20 min), leading to increased cellular oxidizing power(evaluated by ROS levels) and decreased reducing power(evaluated by glutathione(GSH) levels). In addition, we examined the dynamics of cytosolic Ca^2+ and mitochondrial Ca^2+ by confocal laser scanning microscopy and confirmed that Ca^2+ stores in the endoplasmic reticulum were the primary source of H2O2-induced cytosolic Ca^2+ bursts. It is clear that mitochondria have pivotal roles in determining how exogenous oxidative stress affects cell fate. The stress response involves the transfer of Ca^2+ signals between organelles,ROS auto-amplification, mitochondrial dysfunction, and a caspase-dependent apoptotic pathway.目的:通过细胞外过氧化氢(H_2O_2)的刺激建立单个人肺癌SPC-A-1细胞的氧化压力模型。创新点:氧自由基(ROS)涉及多种生物现象,包括有益和有害两个方面。ROS的定量检测和反应网络的评估结果令人期待。但ROS半衰期很短且反应过程很快,因此,我们通过多种手段克服了检测和评估的困难。方法:利用改进的微流控和成像技术测定ROS水平,构建氧反应网络。通过调控线粒体胞浆Ca^(2+)水平、线粒体Ca^(2+)摄取、细胞内ROS自扩增以及内在凋亡途径,确定线粒体在外源氧化压力模式中扮演的角色。结论:研究结果表明1 mmol/L H_2O_2引起细胞O_2^(·-)水平的快速增加,从而导致细胞氧化能力增加和还原能力降低。此外,研究还证实了内质网中储存的Ca^(2+)是H_2O_2诱导的线粒体Ca^(2+)爆发的主要来源。外源氧化压力反应涉及细胞器间Ca^(2+)信号的传递、ROS自身扩增、线粒体功能紊乱和半胱天冬酶依赖性凋亡途径。线粒体在外源性氧化应激影响细胞命运方面发挥着关键作用。

关 键 词：Individual cell Superoxide anion Reactive oxygen species(ROS) dynamics Intrinsic apoptotic pathway Ca2+ signaling 

分 类 号：R73-3[医药卫生—肿瘤]