Lin Wumei, Ye Haiyan
Department of Gynecology, Guangdong Academy of Medical Sciences, Guangdong Provincial People's Hospital, Guangzhou, 510080, China.
J BUON. 2020 Mar-Apr;25(2):750-756.
Ovarian cancer (OC) is perhaps the most difficult problem in gynaecologic oncology; in particular the drug-resistant ovarian cancer remains a challenge for the clinicians. Therefore there is a pressing need for novel and effective chemotherapeutic agents against OC. The main objective of the current research work was to study the anticancer effects of a naturally occurring triterpene acid, ursolic acid, against SKOV-3 OC cells. Its effects on reactive oxygen species (ROS)-mediated apoptosis were also studied along with cell cycle phase distribution and PI3K/AKT signalling pathway.
Cell proliferation was checked by CCK8 cell viability assay. Apoptosis-related studies were examined by fluorescent microscopy using acridine orange (AO)/ethidium bromide (EB) and DAPI staining as well as flow cytometry using annexin V/propidium iodide (PI) assay. Further, western blot assay was used to study effects of ursolic acid on the apoptosis-related protein expressions including Bax, Bcl-2 as well as PI3K/AKT signalling pathway. Effects on cell cycle were examined by flow cytometry while effects on ROS production were evaluated by fluorescent microscopy.
Ursolic acid caused significant reduction in the viability of the SKOV-3 ovarian carcinoma cells in a dose-dependent manner, exhibiting an IC50 of 35 µM in cancer cells and IC50 of 75 µM in normal cell lines (normal ovarian surface epithelial (OSE). Ursolic acid inhibited the viability of cancer cells via induction of apoptotic cell death which was associated with increase in Bax and decrease in Bcl-2 levels. DAPI staining results also confirmed that ursolic acid induced apoptotic cell death. Ursolic acid also induced dose-dependent G2/M phase cell cycle arrest along with causing significant upsurge in ROS production. Western blot analysis revealed that ursolic acid had the potential to inhibit I3K/AKT signalling pathway.
The results of this study clearly indicate that ursolic acid has the potential to be developed as a potent drug candidate against OC provided further in vivo and toxicological studies are carried out.
卵巢癌（OC）可能是妇科肿瘤学中最棘手的问题；尤其是耐药性卵巢癌对临床医生来说仍然是一项挑战。因此，迫切需要新型有效的抗卵巢癌化疗药物。当前研究工作的主要目的是研究天然存在的三萜酸——熊果酸对SKOV-3卵巢癌细胞的抗癌作用。还研究了其对活性氧（ROS）介导的细胞凋亡的影响，以及细胞周期阶段分布和PI3K/AKT信号通路。
通过CCK8细胞活力测定法检测细胞增殖。使用吖啶橙（AO）/溴化乙锭（EB）和DAPI染色的荧光显微镜以及膜联蛋白V/碘化丙啶（PI）测定法的流式细胞术来检测凋亡相关研究。此外，蛋白质免疫印迹分析用于研究熊果酸对凋亡相关蛋白表达的影响，包括Bax、Bcl-2以及PI3K/AKT信号通路。通过流式细胞术检测对细胞周期的影响，而通过荧光显微镜评估对ROS产生的影响。
熊果酸以剂量依赖性方式显著降低SKOV-3卵巢癌细胞的活力，在癌细胞中的IC50为35 μM，在正常细胞系（正常卵巢表面上皮（OSE））中的IC50为75 μM。熊果酸通过诱导凋亡性细胞死亡来抑制癌细胞的活力，这与Bax增加和Bcl-2水平降低有关。DAPI染色结果也证实熊果酸诱导凋亡性细胞死亡。熊果酸还诱导剂量依赖性的G2/M期细胞周期阻滞，并导致ROS产生显著增加。蛋白质免疫印迹分析表明熊果酸有抑制I3K/AKT信号通路的潜力。
本研究结果清楚地表明，只要进一步开展体内和毒理学研究，熊果酸有潜力被开发成为一种有效的抗卵巢癌候选药物。
