五味子甲素增强奥沙利铂对结直肠癌细胞的杀伤作用

Schizandrin A enhances killing effect of oxaliplatin on colorectal cancer cells

背景五味子甲素(schizandrin A,SchA)在多种肿瘤中具有抗癌和逆转多药耐药性的作用,但其对奥沙利铂(oxaliplatin,L-OHP)在结直肠癌细胞的作用并不清楚.目的探讨SchA是否能增强L-OHP对结直肠癌细胞的杀伤作用,并分析其机制.方法将结直肠癌细胞分为对照组、SchA处理组、L-OHP处理组和SchA+L-OHP联合处理组.用噻唑蓝(methyl thiazolyltetrazolium,MTT)法检测细胞活力;流式细胞术法检测细胞凋亡;活性氧簇(reactive oxygen species,ROS)探针检测细胞ROS含量;5,5’,6,6’-四氯-1,1’,3,3’-四乙基苯并咪唑羰花青碘化物(1,1’,3,3’-tetraethyl-5,5’,6,6’-tetrachloroimidacarbocyanineiodide,JC-1)探针评估线粒体膜电位变化;Western blot检测B-细胞淋巴瘤-2(B-cell lymphoma 2,Bcl-2)、Bcl-2相关X蛋白(Bcl-2associatedXprotein,Bax)、细胞色素c(cytochrome c,Cytc)和劈开的半胱氨酸蛋白酶-3(cleavedcysteine proteinase-3,cleaved caspase-3)的表达.结果与L-OHP处理组比较,SchA+L-OHP联合处理组的结直肠癌细胞的细胞活力明显降低,细胞凋亡明显增加.SchA能增强L-OHP导致的结直肠癌细胞内ROS蓄积、Bax和cleaved caspase-3表达、线粒体Cyt c释放,并降低Bcl-2表达.结论SchA增强L-OHP对结直肠癌细胞的杀伤作用,其机制可能与增强细胞内ROS蓄积以及促凋亡相关蛋白表达相关.

BACKGROUND Schizandrin A(SchA) has anticancer and multidrug resistance-reversing effects in a variety of tumors,but its effect on oxaliplatin(L-OHP) in colorectal cancer cells is not clear.AIM To investigate whether SchA can enhance the killing effect of L-OHP on colorectal cancer cells,and to analyze the possible mechanism involved.METHODS Colorectal cancer cells were divided into control group,SchA treatment group,L-OHP treatment group,and SchA + L-OHP treatment group.Cell viability was detected by MTT assay.Cell apoptosis was detected by flow cytometry.The contents of reactive oxygen species(ROS) in cells was detected using a ROS probe.Mitochondrial membrane potential was evaluated by using the 1,1’,3,3’-tetraethyl-5,5’,6,6’-tetrachloroimidacarbocyanine iodide(JC-1) probe.Western blot was used to detect the expression of B-cell lymphoma 2(Bcl-2),Bcl-2 associated X protein(Bax),cytochrome c(Cyt c),and cleaved cysteine proteinase-3(caspase-3) in the cells.RESULTS Compared with the L-OHP treatment group,the viability of colorectal cancer cells in the SchA + L-OHP treatment group was significantly decreased,while apoptosis was significantly increased.SchA could enhance ROS accumulation,Bax and cleaved caspase-3 expression,and mitochondrial Cyt c release,and decrease Bcl-2 expression in colorectal cancer cells induced by L-OHP.CONCLUSION SchA enhances the killing effect of L-OHP on colorectal cancer cells,and the mechanism may be related to the enhancement of intracellular ROS accumulation and the expression of apoptosis-related proteins.