含笑内酯对卵巢上皮性癌细胞的作用及其机制

Study of effects of micheliolide on ovarian cancer cell lines and its mechanism

目的：探讨含笑内酯对卵巢上皮性癌（卵巢癌）细胞的作用及其可能的机制。方法（1）不同浓度（分别为0.25、0.5、1、2.5、5、10、20、50μmol/L）含笑内酯作用卵巢癌细胞系HeyA8、SKOV3细胞及卵巢癌顺铂耐药细胞系A2780/DDP细胞72 h后，四甲基偶氮唑蓝（MTT）比色法检测3种卵巢癌细胞的生长情况，选择抑制作用最为显著的卵巢癌细胞（即HeyA8细胞）用于后续实验。（2）不同浓度（分别为5、10、20μmol/L）含笑内酯作用24 h后，流式细胞仪检测HeyA8细胞的凋亡情况，实时荧光定量PCR技术检测HeyA8细胞中RelA mRNA的表达，蛋白印迹（western blot）法检测HeyA8细胞中核因子κB（NF-κB）信号通路相关蛋白RelA和活化半胱氨酸天冬氨酸蛋白酶9（caspase-9）的表达。结果（1）不同浓度含笑内酯作用72 h后，HeyA8、SKOV3及A2780/DDP细胞的生长均受到明显抑制，且均呈显著的浓度依赖性（P〈0.05）；其50％抑制浓度（IC50）分别为（9.8±2.2）、（12.0±2.1）、（12.8±1.8）μmol/L。选用抑制效果最佳的HeyA8细胞进行后续实验。（2）不同浓度含笑内酯作用24 h后，随着含笑内酯浓度的增高，HeyA8细胞的细胞凋亡比例增高，细胞存活比例下降，细胞中RelA mRNA的表达水平下降，当含笑内酯浓度为20μmol/L时，上述指标分别与其对照（仅加入溶剂者）比较，差异均有统计学意义（P〈0.01）；HeyA8细胞中RelA蛋白的表达强度逐渐减弱，而活化caspase-9蛋白的表达强度逐渐增强。结论含笑内酯对卵巢癌HeyA8、SKOV3及A2780/DDP细胞均有显著的抑制作用，且对HeyA8细胞的抑制作用最明显；其作用机制可能是通过抑制NF-кB信号通路、诱导活化caspase-9蛋白的表达来促进卵巢癌HeyA8细胞的凋亡。

Objective To study the roles of micheliolide on ovarian cancer cells. Methods Firstly, human ovarian cancer cell lines HeyA8, SKOV3 and A2780/DDP were treated with different concentration of micheliolide （0.25, 0.5, 1, 2.5, 5, 10, 20, 50 μmol/L） for 72 hours, then methyl thiazolyl tetrazolium （MTT） assay was used wo detect the growth of the human ovarian cancer cell lines and the stongest inhibited cell line were selected for the following test. Secondly, after HeyA8 cell line was treated with different concentration （5, 10, 20μmol/L） of micheliolide for 24 hours, the HeyA8 cell apoptosis was measured byflow cytometry. Thirdly, the expression of RelA mRNA in HeyA8 cell was detected through real-time PCR, the expressions of nuclear factor κB（NF-κB）signal pathway related protein RelA and the activited cysteinyl aspartate specific proteinase （caspase-9） were detected by western blot analysis. Results （1） The growth of HeyA8, SKOV3 and A2780/DDP cells were all significantly inhibited after being treated with different concentration of micheliolide for 72 hours and the roles of inhibition were all＆nbsp;concentration dependant （P〈0.05）. The half maximal inhibitory concentration （IC50） of HeyA8, SKOV3 and A2780/DDP were （9.8±2.2）, （12.0±2.1） and （12.8±1.8）μmol/L, respectively. We chose HeyA8 cell to do the following expreriments because of its best inhibited effect. （2） After HeyA8 cell was treated with micheliolide of different concentrations, as the concentration increased （20 and 0μmol/L, for example）, the apoptosis rate of HeyA8 cell raised from （7.2±1.0）%to （17.4±1.1）%, the percentage of survived cells reduce from （92.8 ± 1.3）% to （82.6 ± 1.4）%,and the relative mRNA level of RelA decreased from 1.00 ± 0.13 to 0.18 ± 0.00 （P〈0.01）; furthermore, the expression of RelA protein was weaken and the activited caspase-9 protein expression was increased gradually. Conclusions Micheliolide plays a significantly inhibited role in HeyA8, SKOV3 and A2780/DDP cells. The inhibited role of micheliolide inovarian cancer cells might through inhibiting nuclear factor-kappa B （NF-кB） signaling pathway, and inducing the expression of activited caspase-9 protein to promoting apoptosis of HeyA8 cell.