紫丁香苷调控PI3K/Akt/mTOR信号通路诱导乳腺癌细胞凋亡的研究

目的 研究紫丁香苷的抗乳腺癌作用及分子机制,为紫丁香苷的临床应用提供理论依据。方法 MTT检测紫丁香苷对乳腺癌细胞增殖的抑制作用;台盼蓝、TUNEL和Annexin V-FITC/PI染色检测细胞的凋亡状况,Western bolt检测Caspase-3的活化情况,判断细胞凋亡是否发生;检测凋亡相关蛋白B淋巴细胞瘤2（Bcl-2）的表达,结合JC-1染色探讨紫丁香苷对线粒体凋亡途径的影响;运用PI3K激动剂Recilisib做对比,qRT-PCR和Western bolt检测紫丁香苷调控PI3K/Akt/mTOR通路诱导癌细胞凋亡的作用。结果 紫丁香苷对乳腺癌细胞的增殖具有时间和剂量依赖的抑制作用,能诱导癌细胞发生凋亡。进一步研究发现,紫丁香苷处理后,细胞内Caspase-3被激活,Bcl-2表达下降,线粒体膜电位明显丧失,PI3K、Akt和mTOR的mRNA与蛋白质水平表达无明显变化,但蛋白质磷酸化水平明显下降;Recilisib处理后部分抵消了紫丁香苷对乳腺癌细胞凋亡的作用。结论 紫丁香苷对乳腺癌细胞MDA-MB-231和MCF-7具有良好的抑制作用,其通过抑制PI3K/Akt/mTOR信号通路的活化来抑制细胞增殖并诱导细胞发生线粒体途径的凋亡。紫丁香苷是具有开发潜力的抗乳腺癌药物。

Study on Apoptosis of Breast Cancer Cells Induced by Regulation of PI3K/Akt/mTOR Pathway by Syringin

Objective To study the anti-breast cancer effects and molecular mechanisms of syringin, and to provide a theoretical basis for the clinical application of syringin.Methods The inhibitory effect of syringin on the proliferation of breast cancer cells was measured with MTT assay. Trypan blue, TdT-mediated dUTP nick-end labeling (TUNEL), and Annexin V-FITC/PI staining were used to detect apoptosis. Caspase-3 activation was detected via Western blot to determine whether apoptosis occurred. The expression of apoptosis-associated protein B-cell lymphoma-2 (Bcl-2) was detected and the effect of syringin on the mitochondrial apoptosis pathway was investigated via JC-1 staining. The PI3K agonist Recilisib was used for comparison. qRT-PCR and Western blot were used to assess the role of syringin in regulating the PI3K/Akt/mTOR pathway and inducing the apoptosis of cancer cells.Results Syringin had a time- and dose-dependent inhibitory effect on the proliferation of breast cancer cells and induced their apoptosis. A further study showed that after syringin treatment, Caspase-3 was activated, Bcl-2 expression decreased, the mitochondrial membrane potential was significantly reduced, and the mRNA and protein expressions of PI3K, Akt, and mTOR were not significantly changed, but the protein phosphorylation levels were significantly decreased. Recilisib partially limits the effect of syringin on the apoptosis of breast cancer cells.Conclusion Syringin has a good inhibitory effect on MDA-MB-231 and MCF-7 breast cancer cells. It can inhibit cell proliferation and induce mitochondrial apoptosis by inhibiting the activation of the PI3K/Akt/mTOR signaling pathway. Syringin is a potential anti-breast cancer drug.