麦冬皂苷B诱导人宫颈癌HeLa细胞自噬的机制  

Molecular mechanism of ophiopogonin B induced cellular autophagy of human cervical cancer HeLa cells

作　　者：许秋菊[1] 侯莉莉[1] 胡国强[1] 谢松强[1] 

机构地区：[1]河南大学化学生物学研究所,河南开封475004

出　　处：《药学学报》2013年第6期855-859,共5页Acta Pharmaceutica Sinica

基　　金：河南省基础与前沿技术研究项目(102300410095);河南省高校青年骨干教师资助计划(2009GGJS-022)

摘　　要：以人宫颈癌HeLa细胞为研究对象,探讨麦冬皂苷B的抗肿瘤作用及其分子机制。采用MTT检测、流式细胞仪分析、吖啶橙染色、Lyso-Tracker Red染色及HeLa-GFP-LC3转染细胞实验,分别检测HeLa细胞的增殖、凋亡及自噬。结果表明,麦冬皂苷B可抑制细胞增殖,但并不诱导细胞凋亡,可诱导细胞自噬,并引起自噬标志性蛋白Beclin-1表达增加及LC3I转变为LC3II;自噬抑制剂3-MA不但可以抑制该自噬作用而且几乎完全逆转其抗增殖作用,提示其生长抑制作用为自噬依赖性的。Western blotting检测结果表明,麦冬皂苷B抑制AKT、mTOR和p70S6K的磷酸化并上调PTEN,但并不引起Caspase3的活化及PARP的切割。因此,麦冬皂苷B抑制HeLa细胞增殖与凋亡无关,而是通过抑制Akt/mTOR信号通路诱导其发生自噬。This study is to investigate the antitumor activity of ophiopogonin B （OP-B）. MTT assay, flow cytometric analysis, acridine orange staining, Lyso-Tracker Red staining and HeLa-GFP-LC3 transfect cells assay were used to detect the proliferation activity, apoptosis and autophagy of HeLa cells. The results showed that OP-B exerted potent antiproliferative activity on HeLa cells, the cell growth inhibition effect of OP-B was not due to apoptosis and OP-B could induce autophagy of HeLa cells. OP-B also induced the protein expression up-regulation of Beclin-1 and promoted LC3 I transformation LC3 II, which were representative proteins of autophagy. Furthermore, 3-MA, an inhibitor of autophagy, not only inhibited OP-B-mediated autophagy but also almost completely reversed the antiproliferative effect of OP-B, suggesting that the growth inhibition effect of OP-B was autophagy dependent. Western blotting demonstrated that OP-B inhibited the phosphorylation of Akt and its＇ downstream vital protein, such as mTOR and p70S6K. In addition, OP-B also induced the protein expression up-regulation of PTEN, which is a negative regulation protein for Akt/mTOR signaling pathway. However, OP-B did not affect the protein expression of total Akt. Collectively, the antitumor effects of OP-B were autophagy-dependent via repression Akt/mTOR signaling pathway. Therefore, OP-B is a prospective inhibitor of Akt/mTOR and may be used as an alternative compound to treat cervical carcinoma.

关 键 词：麦冬皂苷B 抗肿瘤作用 自噬 细胞凋亡 AKT 

分 类 号：R963[医药卫生—微生物与生化药学]