姜黄素抑制人胃癌BGC-823细胞生长并诱导其凋亡的机制研究

目的:探讨姜黄素抑制人胃癌BGC-823细胞生长并促人胃癌BGC-823细胞凋亡的生物学作用及其调控机制。方法:常规体外培养对数生长期胃癌BGC-823细胞,细胞分为对照组,低、中、高姜黄素处理组四组,姜黄素浓度分别为0mg/L5,mg/L1,0mg/L,20mg/L。姜黄素处理24h后,采用甲基噻唑(MTT)比色法及流式细胞仪测定细胞增殖水平及细胞凋亡率;采用免疫组化法测定细胞内Bax、Bcl-2蛋白表达;采用PCR检测Caspase-3的mRNA表达水平。结果:MTT检测显示姜黄素能抑制人胃癌BGC-823细胞増殖,呈现浓度依赖性;流式细胞仪显示姜黄素能有效诱导细胞的凋亡,呈现浓度依赖性,其中20mg/L姜黄素处理24h后细胞凋亡率为48.3%;免疫组化试验表明姜黄素处理使人胃癌BGC-823细胞中Bax表达水平上调,同时Bcl-2蛋白表达水平下调;且细胞中Caspase-3的mRNA表达水平受姜黄素诱导而增高。结论:姜黄素对人胃癌BGC-823细胞的增殖具有明显抑制作用,呈浓度依赖性促进细胞凋亡,这种生物学效应可能与激活Bax蛋白表达、抑制Bcl-2蛋白表达而活化Caspase-3的信号通路有关。该研究为深入探讨姜黄素诱导人胃癌BGC-823细胞凋亡的机制提供了重要依据。

Introduction of Mechanism on Human Gastric Cancer Cell Line BGC-823 Growth and Inducing Apoptosis

Objective:The study was aimed to investigate the effect and mechanism of curcumin induced apoptosis on human gastric cancer cell line BGC-823.Methods:Cultured BGC-823 cells were divided into control,lower dose curcumin,middle dose curcumin and higher dose curcumin groups,and concentration of curcumin of each group were 0mg/L,5mg/L,10mg/L,20mg/L respectively.After pretreated with curcumin for 24h,the proliferation level was measured by MTT assay,cell apoptosis level was detected with flow cytometr.Whilst Bax、Bcl-2 protein expression levels were tested by immunohistochemisty assay and Caspase-3 mRNA expression level was tested by RT-PCR.Results:MTT assay showed the inhibitory effect of curcumin on proliferation of BGC-823 cells was dose dependent.Treatment with increasing dose of curcumin in the cells caused a dose-dependent apoptosis by flow cytometry analysis,such as 20mg/L curcumin pretreatment cause 48.3% cells apoptosis.Immunohistochemisty assay data indicated that Bax expression level was enhanced in curcumin treatment BGC-823 cells,and Bcl-2 protein expression level was repressed.And RT-PCR indicated that Caspase-3 mRNA expression was induced by curcumin.Conclusion:The promotion effect of cucumin on apoptosis of BGC-823 cells was dose dependent,which correlated with Bax up-regulation as well as Bcl-2 down-regulation and Caspase-3 activation signal transduction pathway.The data offer the clue for further understanding the inhibition mechanism of cucumin on human gastric cancer cell line BGC-823.