中文摘要：

目的 探讨白头翁皂苷D对人乳腺癌MCF-7细胞的体内外抗肿瘤作用及其机制。方法 采用MTT法和吉姆萨染色,考察白头翁皂苷D对人MCF-7细胞体外增殖抑制的影响;建立MCF-7细胞裸鼠移植瘤模型,考察白头翁皂苷D体内抗肿瘤作用;HE染色和透射电镜实验考察肿瘤组织形态学和超微结构的变化;采用Western Blot法检测MCF-7细胞中Bcl-2、Caspase-3及PI3K/AKT/mTOR途径相关蛋白PI3K-p85、p-AKT、p-mTOR、p-p70S6K的表达。结果 白头翁皂苷D可抑制MCF-7细胞的增殖,且呈剂量依赖关系;裸鼠体内实验结果显示白头翁皂苷D可抑制肿瘤的生长,30.0 mg·kg^-1剂量组瘤体质量明显降低,与模型组比较,差异有统计学意义（P〈0.01）;形态学观察结果也显示白头翁皂苷D对MCF-7细胞具有凋亡作用,且随着给药剂量的增加变化越明显;白头翁皂苷D（15.0,20.0,25.0μmol·L^-1）不同剂量组均可抑制MCF-7细胞中Bcl-2、Caspase-3蛋白的表达,与对照组比较,差异均有统计学意义（P〈0.01）;白头翁皂苷D还可下调PI3K/AKT/mTOR信号传导通路相关蛋白PI3K-p85、p-AKT、p-mTOR、p-p70S6K蛋白的表达,20.0,25.0μmol·L^-1剂量组与对照组比较,差异均有统计学意义（P〈0.05,P〈0.01）。结论 白头翁皂苷D对MCF-7细胞有显著的体内外抗肿瘤作用,其机制可能是通过下调PI3K/AKT/mTOR信号传导通路诱导细胞凋亡。

英文摘要：

Objective To study the effect and mechanism of pulsatilla saponin D on breast cancer tumor （MCF-7） cells in vitro and in vivo. Methods MTr assay and Giemsa staining method were used to evaluate proliferation inhibition of pulsatilla D on MCF-7 cells; the effect of pulsatilla saponin D on transplant tumor （MCF-7） cells in athymic nude mice was investigated in vivo; the change of mierostructure and uhrastructure of tumor tissue was observed by HE staining and electron microscopy. The expression levels of Bcl-2, Caspase-3, and proteins related to PI3K-AKT-mTOR pathway in MCF-7 cells were detected by Western Blot. Results Pulsatilla saponin D inhibited the proliferation of MCF-7 cells in a dose-dependent manner; the tumor weight of pu｜satilla saponin D （30.0 mg＇kg-~） treated transplant tumor（MCF-7） in athymic nude mice was decreased significantly compared with model group（P 〈 0.01 ）. Morphologic observation revealed that pulsatilla saponin D induced apoptosis in the MCF-7 cells, this effect was gradually stronger with dose increasing. Pulsatilla saponin D（ 15.0, 20.0, 25.0μmol·L^-1）could down-regulate the expression of Bcl-2 and Caspase-3 proteins in MCF-7 cells （P 〈 0.01） ; and suppress PI3K/AKT/mTOR cell signal pathway protein expression including PI3K-p85, p-AKT, p-mTOR and p-p70S6K （20.0, 25.0μmol·L^-1, P 〈 0.01, P 〈 0.05）. Conclusion Pulsatilla saponin D has significant antitumor activity and induces apoptosis in MCF-7 cells, the mechanism may be related to PI3K/AKT/mTOR cell signal pathway.