Wang Ye, Zhu Zhiling
Department of Integration of Western and Traditional Medicine, Obstetrics and Gynecology Hospital of Fudan University, Shanghai, China.
Arch Med Sci. 2019 Jul;15(4):1017-1027. doi: 10.5114/aoms.2018.77068. Epub 2018 Jul 10.
Oridonin, which is isolated from the Chinese herb Rabdosia rubescens, has been reported to exhibit an anti-tumorous effect on different cancers. In this study, we investigated the molecular mechanism by which oridonin suppresses human ovarian cancer.
The inhibition of oridonin on cell proliferation was assessed by CCK8 assay. Cell cycle and apoptosis were analyzed by flow cytometry, staining with propidium iodide (PI) or annexin-V/PI respectively. The metastasis rate was evaluated using a transwell migration assay. The expression of metastasis-associated genes and mTOR pathway related genes were detected by western blot.
We demonstrated that oridonin suppressed the proliferation and blocked the cell cycle in G1/S phage and induced apoptosis in SKOV3 and A2780 cells ( < 0.01). We further found that the mTOR signaling pathway was suppressed by the treatment with oridonin, and the activation of the mTOR pathway attenuated the anti-tumorous effect of oridonin in human ovarian cancer cells, suggesting that the mTOR pathway was involved in the anti-tumorous process of oridonin. Additionally, the activation of the mTOR pathway by an exogenous activator reduced the expression level of FOXP3 ( < 0.01), thus providing evidence that FOXP3 is a factor that is necessary for the anti-tumorous effect of oridonin, and is negatively regulated by the mTOR pathway.
These results suggested that oridonin suppressed the mTOR signaling pathway, up-regulated the FOXP3 level, and inhibited metastasis of human ovarian cancer cells.
冬凌草甲素是从中药冬凌草中分离得到的，据报道其对不同癌症具有抗肿瘤作用。在本研究中，我们探究了冬凌草甲素抑制人卵巢癌的分子机制。
采用CCK8法评估冬凌草甲素对细胞增殖的抑制作用。分别用碘化丙啶（PI）或膜联蛋白V/PI染色，通过流式细胞术分析细胞周期和凋亡情况。使用Transwell迁移实验评估转移率。通过蛋白质免疫印迹法检测转移相关基因和mTOR信号通路相关基因的表达。
我们证明冬凌草甲素抑制SKOV3和A2780细胞的增殖，使细胞周期阻滞于G1/S期并诱导细胞凋亡（P<0.01）。我们进一步发现，冬凌草甲素处理可抑制mTOR信号通路，而mTOR信号通路的激活减弱了冬凌草甲素对人卵巢癌细胞的抗肿瘤作用，这表明mTOR信号通路参与了冬凌草甲素的抗肿瘤过程。此外，外源性激活剂激活mTOR信号通路可降低FOXP3的表达水平（P<0.01），从而证明FOXP3是冬凌草甲素发挥抗肿瘤作用所必需的因子，且受mTOR信号通路负调控。
这些结果表明，冬凌草甲素抑制mTOR信号通路，上调FOXP3水平，并抑制人卵巢癌细胞的转移。
