竹节香附素A体外诱导乳腺癌细胞凋亡的作用机制研究

Mechanism of Raddeanin A in Inducing Apoptosis of Breast Cancer Cells in Vitro

目的:探讨竹节香附素A(RaA)体外抗乳腺癌的作用机制。方法:体外培养乳腺癌细胞(MDA-MB-231),分别用RaA及RaA联合乙酰半胱氨酸(NAC)干预后检测相关蛋白及信号通路的变化情况。结果:与空白组比较,RaA组抑制MDA-MB-231细胞增殖,促进MDA-MB-231细胞凋亡(P<0.01),促进MDA-MB-231细胞线粒体膜电位坍塌,提升MDA-MB-231细胞的活性氧(ROS)水平(P<0.01),提升MDA-MB-231细胞B细胞淋巴瘤-2相关X蛋白(Bax)/B细胞淋巴瘤-2蛋白(Bcl-2)的比值(P<0.01),上调MDA-MB-231细胞色素C(Cyt-C)、信号转导及转录激活蛋白3(STAT3)和抑癌基因53(P53)的蛋白水平(P<0.05,P<0.01),下调MDA-MB-231细胞STAT3的磷酸化水平(P<0.05,P<0.01);与RaA组比较,RaA联合NAC组可降低MDA-MB-231细胞的ROS水平(P<0.01),降低MDA-MB-231细胞Bax/Bcl-2的比值(P<0.01),下调MDA-MB-231细胞Cyt-C、活化胱天蛋白酶-3(active CASP3,CCASP3)和P53的蛋白水平(P<0.01),上调STAT3磷酸化水平(P<0.01)。结论:RaA通过激活ROS/STAT3/P53信号通路诱导线粒体凋亡在体外发挥抗乳腺癌作用。

Objective:To investigate the effect and mechanism of raddeanin A(RaA)in treating breast cancer.Methods:Breast cancer MDA-MB-231 cells were cultured in vitro and treated with RaA and RaA combined with n-acetylcysteine(NAC),respectively.The changes of related proteins and signaling pathways were then examined.Results:Compared with the control group,RaA inhibited the proliferation,induced the apoptosis,promoted the mitochondrial membrane potential collapse,and elevated the reactive oxygen species(ROS)level of MDA-MB-231 cells(P<0.01).In addition,RaA increased the Bcl-2-assicated X protein(Bax)/B-cell lymphoma 2(Bcl-2)ratio(P<0.01),up-regulated the protein levels of cytochrome C(Cyt-C),cleaved CASP3(CCASP3),and cancer suppressor gene 53(P53)(P<0.05,P<0.01),and down-regulated the phosphorylation level of signal transducer and activator of transcription 3(STAT3)(P<0.05,P<0.01)in MDA-MB-231 cells.Compared with the RaA group,NAC combined with RaA lowered the ROS level,decreased the Bax/Bcl-2 ratio,down-regulated the protein levels of Cyt-C,CCASP3,and P53,and up-regulated the phosphorylation level of STAT3 in MDA-MB-231 cells(all P<0.01).Conclusion:RaA exerted the anti-breast cancer effect in vitro by activating the ROS/STAT3/P53 signaling pathway to induce mitochondrial apoptosis.