飞燕草素通过AKT/mTOR通路诱导HER-2+乳腺癌细胞自噬

摘要

Objective:To explore the effect of delphinidin on breast cancer and the underlying mechanisms.Methods:Human epidermal growth factor receptor-2 (HER-2) positive breast cancer cells MDA-MB-453 were treated by delphinidin.Proliferation of MDA-MB-453 cells was detected by CCK-8 after 48 h.TdT-mediated dUTP nick end labeling (TUNEL) assay and Western blot were used to explore apoptotic status for MDA-MB-453 cells.Fluorescence dot assay,immunofluorescence,and Western blot were used to identify autophagy in breast cancer cells.Results:Delphinidin suppressed proliferation of MDA-MB-453 cells.Delphinidin increased the number of TUNEL positive cells.Delphinidin downregulated the expression of caspase-3 and caspase-9,while upregulated the expression of cleaved caspase-3 and cleaved caspase-9 in a dose-dependent manner.Delphinidin enhanced the number of GFP-LC3 punctate dots,LC3 immunofluorescence dots and the expression of LC3-Ⅱ and ATG5.Delphinidin inhibited the expression of proteins in mTOR signaling pathway,induding AKT,mTOR,eIF4E and p70s6k.Conclusion:Delphinidin induced apoptosis and autophagy by inhibition of AKT/mTOR pathway in HER positive breast cancer cells.%目的:研究飞燕草素对HER-2+乳腺癌细胞MDA-MB-453自噬的诱导作用及其分子机制.方法:以不同浓度飞燕草素处理MDA-MB-453细胞,CCK-8检测细胞增殖情况;TdT介导的脱氧尿嘧啶缺口末端标记(TdT-mediated dUTP nick end labeling,TUNEL)和Western印迹检测细胞凋亡和与凋亡相关蛋白的表达;荧光斑点、免疫荧光和Western 印迹检测白噬的诱导情况和诱导机制.结果:飞燕草素抑制MDA-MB-453细胞增殖,增加TUNEL阳性细胞数,下调caspase-3和caspase-9蛋白活性,上调裂解的caspase-3和裂解的caspase-9蛋白活性.飞燕草素增加GFP-LC3荧光斑点数、LC3免疫荧光斑点数、LC3-II和ATG5蛋白表达.飞燕草素下调mTOR通路蛋白AKT,mTOR,eIF4E和p70s6k蛋白活性.结论:飞燕草素诱导HER-2+乳腺癌细胞MDA-MB-453凋亡的同时通过抑制AKT/mTOR通路诱导细胞自噬.