红花多糖通过阻断PI3K/Akt/mTOR通路诱导人乳腺癌MDA-MB-435细胞凋亡的机制研究

Mechanism research of safflower polysaccharide inducing apoptosis of human breast cancer MDA-MB-435 cells by interrupting PI3K/Akt/mTOR Pathway

目的研究红花多糖通过阻断PI3K/Akt/mTOR通路诱导人乳腺癌MDA-MB-435细胞凋亡的作用及其作用机制。方法将MDA-MB-435细胞分为对照组和红花多糖0.5、1.0 mg/mL组。MTT法及流式检测仪分别检测不同质量浓度红花多糖对MDA-MB-435细胞生长及凋亡的影响;RT-PCR及Western blotting法分别检测不同质量浓度红花多糖对MDA-MB-435细胞PI3K、Akt、mTOR mRNA和蛋白表达的影响。结果与对照组比较,红花多糖0.5 mg/mL组MDA-MB-435细胞抑制率为(21.52±2.43)%,红花多糖1.0 mg/mL组细胞抑制率为(27.73±3.75)%,显著高于红花多糖0.5 mg/m L组(P<0.05);与对照组比较,红花多糖能够显著提高MDA-MB-435细胞凋亡率(P<0.01),且呈剂量依赖性。RT-PCR及Western blotting实验结果显示,与对照组比较,红花多糖能够使MDA-MB-435细胞中PI3K、Akt、mTOR mRNA和蛋白表达显著降低(P<0.05、0.01)。结论红花多糖能有效抑制MDA-MB-435细胞的生长,促进其凋亡,作用可能是通过对PI3K/Akt/mTOR通路的阻断实现的。

Objective To investigate the effect of safflower polysaccharide on apoptosis of human breast cancer MDA-MB-435 cells by blocking PI3K/Akt/mTOR pathway and explore its mechanism. Methods MDA-MB-435 cells were divided into control group and safflower polysaccharide 0.5 and 1.0 mg/mL groups. MTT assay and flow cytometry were used to detect the effects of different concentrations of safflower polysaccharide on the growth inhibition and apoptosis of MDA-MB-435 cells. RT-PCR and Western blotting were used to detect the effect of different concentrations of safflower polysaccharides on the mRNA and protein expression of PI3K, Akt, and mTOR in MDA-MB-435 cells. Results Compared with the control group, the inhibition rate of MDA-MB-435 cells in safflower polysaccharide 1.0 mg/mL group was（27.73 ± 3.75）%, which was significantly higher than that [（21.52 ± 2.43）%] in safflower polysaccharide 0.5 mg/mL group（P〈0.05）. Compared with the control group, safflower polysaccharide could significantly increase the apoptosis rate of MDA-MB-435 cells in a dose-dependent manner（P〈0.01）. The results of RT-PCR and Western blotting showed that, compared with the control group, safflower polysaccharide significantly decreased the mRNA and protein expression of PI3K, Akt, and mTOR in MDA-MB-435 cells（P〈0.05, 0.01）. Conclusion Safflower polysaccharide can effectively inhibit the growth of MDA-MB-435 cells and promote their apoptosis, which may be achieved by blocking the PI3K/Akt/mTOR pathway.