五味子乙素介导Wnt/β-catenin信号通路诱导乳腺癌MCF-7细胞凋亡的分子机制

Molecular Mechanism of Schisandrin B Inducing the Apoptosis of Mammary Cancer MCF-7 Cells through Mediating Wnt/β-catenin Signaling Pathway

目的:研究五味子乙素对乳腺癌MCF-7细胞增殖、凋亡的影响,及其对Wnt/β-catenin信号通路的作用。方法:CCK8法检测五味子乙素对MCF-7细胞增殖的影响,流式细胞仪测定五味子乙素对MCF-7细胞凋亡率及细胞周期分布的影响,Western Blot技术测定MCF-7细胞中调控细胞周期相关蛋白及Wnt/β-catenin信号通路关键蛋白的表达水平。结果:与对照组相比,五味子乙素干预组MCF-7细胞相对存活率显著降低(P<0.05),凋亡率显著升高(P<0.05);五味子乙素能够将细胞停留在G1期及G2/M期,还能显著抑制细胞周期蛋白Cyclin A、Cyclin B、Cyclin D、Cyclin E以及周期蛋白依赖性激酶(cyclin-dependent kinases,CDK),锥虫特异性RNA结合蛋白(trypanosome-specific RNA binding proteins,p34)的表达(P<0.05);显著抑制Wnt/β-catenin信号通路分泌型糖蛋白Wnt及糖原合成酶激酶3β(glycogen synthase Kinase 3 Beta,GSK-3β)蛋白的表达(P<0.05),但五味子乙素与Wnt激动剂DKK2共同干预细胞后,上述蛋白表达量与五味子乙素组相比,差异有统计学意义(P<0.05)。结论:五味子乙素可能通过干扰MCF-7细胞中Wnt/β-catenin信号传导而发挥有效的抗增殖及促凋亡的作用。

Objective: To study the effects of schisandrin B on the proliferation and apoptosis of mammary cancer MCF-7 cells, and its function on Wnt/β-catenin signaling pathway. Methods: CCK8 method was used to detect its influence on the proliferation of MCF-7 cells, flow cytometry to measure its influence on the apoptosis rate of MCF-7 cells and the distribution of cellular cycle, Western blot technology to measure the expressions of key protein in Wnt/β-catenin signaling pathway and the related protein of regulating cellular cycle in MCF-7 cells.Results: Compared with the control group, the relative survival rates of MCF-7 cells reduced in the intervention group of schisandrin B(P<0.05), apoptosis rate rose notably(P<0.05);flow cytometry analysis suggested that the intervention with schisandrin B could arrest the cells at G1 and G2/M phases, and schisandrin B could notably inhibit the expressions of CDK and p34, cellular cycle protein Cyclin A, Cyclin B, Cyclin D and Cyclin E(P<0.05);it could notably inhibit the expressions of Wnt/β-catenin signaling pathway key proteins Wnt and GSK-3β(P<0.05),while after intervened the cells with schisandrin B and Wnt agonists, the differences were significant when the groups were compared with schisandrin B group in the expressions of the above protein(P <0.05). Conclusion:Schisandrin B could play the effective roles of promoting the proliferation and apoptosis which might be through interfering the transduction of Wnt/β-catenin signal in MCF-7 cells.