3-溴丙酮酸诱导人乳腺癌SK-BR-3细胞凋亡及对细胞线粒体膜电位的影响

Effect of 3-bromopyruvate on mitochondrial membrane potential and apoptosis of human breast carcinoma SK-BR-3 cells

目的探讨糖酵解抑制剂3-溴丙酮酸(3-BrPA)诱导乳腺癌细胞SK-BR-3凋亡的作用及其可能相关机制。方法 MTT法检测3-BrPA对乳腺癌细胞SK-BR-3增殖的抑制作用;碘化丙啶(PI)单染流式细胞术检测细胞凋亡;ATP检测试剂盒检测细胞内ATP水平;DHE荧光探针标记法检测细胞内超氧阴离子水平;线粒体膜电位检测试剂盒(JC-1)检测细胞线粒体膜电位。结果MTT结果显示,3-BrPA可抑制SK-BR-3细胞的增殖活性,且呈浓度和时间依赖性。80、160、320μmol·L-1的3-BrPA诱导SKBR-3细胞24 h的凋亡率分别为6.7%、22.3%、79.6%。80、160、320μmol·L-13-BrPA作用于SK-BR-3细胞5 h后,细胞内ATP水平与对照组相比分别为87.7%、60.6%、23.7%。160μmol·L-1的3-BrPA增加SK-BR-3细胞中活性氧的生成,同时使细胞线粒体膜电位降低。结论 3-BrPA可以抑制乳腺癌细胞SK-BR-3的增殖活性,引起线粒体膜电位降低,并且诱导其凋亡,机制可能与抑制肿瘤细胞的糖酵解从而减少ATP的产生并升高细胞内活性氧的水平有关。

Objective To study the effect of glycolysis inhibitor 3-bromopyruvate （3-BrPA） in inducing apoptosis of human breast carcinoma cells SK-BR-3 and the possible mechanism. Methods MTT assay was used to detect the growth inhibition induced by 3-BrPA in breast cancer cells SK-BR-3. The apoptotic cells were detected by flow cytometry with propidium iodide （PI）. ATP levels in the cells were detected by ATP assay kit, and DHE fluorescent probe technique was used to determine superoxide anion levels; the mitochondrial membrane potential was assessed using JC-1 staining assay. Results MTT assay showed that the proliferation of SK-BR-3 cells was inhibited by 3-BrPA in a time- and concentration-dependent manner. Exposure to 80, 160, and 320μmol·L-1 3-BrPA for 24 h resulted in cell apoptosis rates of 6.7%, 22.3%, and 79.6%, respectively, and the intracellular ATP levels of SK-BR-3 cells treated with 80, 160, 320μmol·L-1 3-BrPA for 5 h were 87.7%, 60.6%, and 23.7%of the control levels. 3-BrPA at 160μmol·L-1 increased reactive oxygen levels and lowered mitochondrial membrane potential of SK-BR-3 cells. Conclusion 3-BrPA can inhibit cell proliferation, reduce the mitochondrial membrane potential and induce apoptosis in SK-BR-3 cells, the mechanism of which may involve a reduced ATP level by inhibiting glycolysis and increasing the reactive oxygen level in the cells.