Department of Thermobiology, Institute of Biophysics, Faculty of Biology and Environmental Protection, University of Lodz, Pomorska 141/143, 90-236 Lodz, Poland.
Toxicol In Vitro. 2013 Feb;27(1):239-49. doi: 10.1016/j.tiv.2012.09.006. Epub 2012 Sep 17.
Epothilones are a new group of compounds with action mechanisms similar to taxanes. The aim of this study was to compare the effects of epothilone A (Epo A) and epothilone B (Epo B) on ovarian cancer cell line SKOV-3 with those of paclitaxel (PTX), a classic taxane. We evaluate glycoprotein P (P-gp) activity in the ovarian cancer cell line. Apoptotic and necrotic cell levels were measured by double staining with Hoechst 33258 and propidium iodide (PI) as well as Annexin V staining. The production of reactive oxygen species (ROS) and changes in mitochondrial membrane potential (ΔΨm) in cells exposed to Epo A, Epo B and PTX were studied using specific fluorescence probes, DCFH(2)-DA (2',7'-dichlorodihydrofluorescein diacetate) and JC-1 (5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolcarbocyanine). The cytotoxic activity of the drugs was determined by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide) test. All probes were analyzed in both the presence and absence of the antioxidant N-acetylcysteine (NAC). The results obtained demonstrated that the antiproliferative capacity of Epo A and Epo B in SKOV-3 cell line (measured as IC(50) after 72 h continuous treatment) was six and five times greater than that of PTX's respectively. Epothilones induced timecourse-dependent apoptosis and necrosis. Apoptotic and necrotic events were partially blocked by NAC, indicating ROS played a substantial role in epothilone-induced apoptosis. Cell death was also associated with a decrease in mitochondrial membrane potential, which was more pronounced after treatment with epothilones as compared to paclitaxel.
埃坡霉素是一组作用机制类似于紫杉烷的新型化合物。本研究旨在比较埃坡霉素 A（Epo A）和埃坡霉素 B（Epo B）对卵巢癌细胞系 SKOV-3 的作用与紫杉醇（PTX）的作用，紫杉醇是一种经典的紫杉烷。我们评估了卵巢癌细胞系中的糖蛋白 P（P-gp）活性。通过用 Hoechst 33258 和碘化丙啶（PI）双重染色以及 Annexin V 染色来测量凋亡和坏死细胞的水平。使用特异性荧光探针 DCFH（2）-DA（2',7'-二氯二氢荧光素二乙酸酯）和 JC-1（5,5',6,6'-四氯-1,1',3,3'-四乙基苯并咪唑羰花青）研究了 Epo A、Epo B 和 PTX 处理的细胞中活性氧物种（ROS）的产生和线粒体膜电位（ΔΨm）的变化。通过 MTT（3-（4,5-二甲基噻唑-2-基）-2,5-二苯基四氮唑溴盐）试验测定药物的细胞毒性活性。在存在和不存在抗氧化剂 N-乙酰半胱氨酸（NAC）的情况下分析了所有探针。结果表明，Epo A 和 Epo B 在 SKOV-3 细胞系中的抗增殖能力（以 72 小时连续处理后 IC50 测量）分别是 PTX 的六倍和五倍。埃坡霉素诱导了时间依赖性的凋亡和坏死。NAC 部分阻断了凋亡和坏死事件，表明 ROS 在埃坡霉素诱导的凋亡中起重要作用。细胞死亡也与线粒体膜电位的降低有关，与紫杉醇相比，埃坡霉素处理后降低更为明显。
