粉防己碱诱导雌激素受体阳性乳腺癌细胞自噬与凋亡的机制研究

Mechanism of Tetrandrine Inducing Autophagy and Apoptosis of Estrogen Receptor Positive Breast Cancer Cells

目的探究粉防己碱(TET)对雌激素受体(ER)阳性乳腺癌细胞BT474内质网应激、细胞自噬和凋亡的影响。方法对数期BT474细胞以5、15、30μmol/L TET进行处理,以缓冲液处理细胞作为对照组,处理72 h。检测4组细胞增殖能力和细胞凋亡水平,检测细胞自噬相关蛋白Beclin1和LC3-Ⅱ,内质网应激通路相关蛋白PERK、IRE1、ATF6和葡萄糖调节蛋白78(GRP78)的表达水平。结果与对照组比较,TET 5、15、30μmol/L组细胞活力显著降低,细胞凋亡率显著增高,且呈浓度依赖性(P<0.05,P<0.01)。与对照组比较,TET 5、15、30μmol/L组凋亡相关蛋白(Beclin1、LC3-Ⅱ)和自噬相关蛋白(GRP78、p-PERK、p-eIF2α、CHOP)表达水平显著升高,且呈浓度依赖性(P<0.05,P<0.01)。TET 15、30μmol/L组ATF6表达水平高于对照组和5μmol/L组,且30μmol/L组高于15μmol/L组(P<0.01)。结论TET通过内质网应激激活ER阳性乳腺癌细胞BT474细胞自噬,从而促进细胞凋亡,抑制细胞增殖。

Objective To investigate the effects of Tetrandrine(TET)on endoplasmic reticulum stress,autophagy and apoptosis in estrogen receptor positive(ER+)breast cancer cell line BT474.Methods BT474 cells in the log phase were treated with 5,15,and 30μmol/L TET,and the cells that were treated with buffer were served as control group,and the treatments were for 72 h.Among 4 groups,proliferation abilities and apoptosis levels of cells,expressions of autophagy-related proteins Beclin1 and LC3-Ⅱ,endoplasmic reticulum stress pathway-related protein kinase RNA-like ER kinase(PERK),inositol-requiring enzyme-1(IRE1)and activating transcription factor-6(ATF6)and glucose-regulated protein 78(GRP78)were detected.Results Compared with those in control group,cell viabilities were significantly reduced,while apoptosis rates were significantly increased in a concentration-dependent manner in 5,15,and 30μmol/L TET groups(P<0.05,P<0.01).Compared with those in control group,expressions of apoptosis-related proteins(Beclin1,LC3-Ⅱ)and autophagy-related proteins(GRP78,p-PERK,p-eIF2α,CHOP)were significantly increased in a concentration-dependent manner in 5,15,and 30μmol/L TET groups(P<0.05,P<0.01).ATF6 expressions in 15 and 30μmol/L TET groups were significantly higher than those in control group and 5μmol/L TET group,and the expression in 30μmol/L TET group was significantly higher than that in 15μmol/L group(P<0.01).Conclusion Tetrandrine may activate autophagy so as to promote apoptosis and inhibit proliferation of ER+breast cancer cell line BT474 through endoplasmic reticulum stress.