应用VPA调节组蛋白乙酰化修饰对肿瘤细胞Caspase的影响  

Modulation of Caspase expression by up-regulating histone acetylizad level with VPA

作　　者：赵霞[1] 时昌文[2] 孙京杰[2] 曹莉莉[2] 李杰[3] 于振海[3] 

机构地区：[1]山东省千佛山医院检验科,济南250014 [2]山东省千佛山医院普外中心试验室,济南250014 [3]山东省千佛山医院普外中心,济南250014

出　　处：《中国免疫学杂志》2009年第3期229-233,共5页Chinese Journal of Immunology

基　　金：山东省医药卫生科技发展计划青年基金(2007QZ019)

摘　　要：目的：探讨应用组蛋白脱乙酰酶抑制剂丙戊酸钠（VPA）调节染色体组蛋白低乙酰化修饰对肿瘤细胞Caspase3、Caspase8、Caspase9蛋白表达及活性的影响,同时通过检测VPA与Caspase3、Caspase8、Caspase9特异性抑制剂协同作用后细胞凋亡的变化加以验证。方法：应用0.75~4.0 mmol/L VPA干预肝癌细胞HepG2、胃癌细胞BGC-823、乳腺癌细胞MCF-7 48小时后,流式细胞术分析细胞凋亡的变化;分光光度法检测Caspase3、Caspase8、Caspase9活性;流式细胞仪间接免疫荧光法定量分析Caspase3、Caspase8、Caspase9蛋白表达。结果：0.75~4.0 mmol/L VPA干预48小时后,FCM分析可见HepG2、BGC-823、MCF-7细胞凋亡率显著增加,与对照组比较差异有显著意义（P〈0.001）并且呈剂量依赖趋势;HepG2、BGC-823、MCF-7细胞Caspase3、Caspase9蛋白表达均被明显上调、活性升高,与对照组相比有显著差异（P〈0.001）;Caspase8活性及蛋白表达在HepG2、MCF-7细胞未见明显改变,BGC-823细胞仅轻度增加。VPA与Caspase3、9相应特异性抑制剂共同作用后,Caspase3、Caspase9活性被抑制,细胞凋亡率较VPA单独干预组显著降低（P〈0.005）;VPA与Caspase8特异性抑制剂共同作用组细胞凋亡率与VPA单独作用组比较无明显变化（P〉0.05）。结论：应用VPA干预组蛋白乙酰化修饰对HepG2、BGC-823、MCF-7细胞Caspase3、Caspase9蛋白表达及活性可起明显的调控作用;对Caspase8的调控作用则随肿瘤细胞来源及表型的不同而有所差异,但总体趋势不明显。Objective：To investigate modulation of a specific HDAC inhibitor,Valproate acid sodium（VPA）,on expression of Caspase3,Caspase8,Caspase9 by inhiting HDAC,as well as apoptosis rate of cancer cells treated with VPA and the specific inhibitors of Caspase3,Caspase8,Caspase9.Methods：Heptocellular carcinoma cells-HepG2,gastric carcinoma cells-BGC-823 and breast cancer cells-MCF-7 were cultured with 0.75-4.0 mmol/L of VPA for 48 hrs in vivo,apoptosis was analyzed by flow cytometry with Annexin V/PI assay.The activities and protein expressions of Caspase3,Caspase8,Caspase9 were detected by spectrophotometry and indirect immunofluorescence technique.Results：Contrary to control groups,VPA at concentrations between 0.75 and 4.0 mmol/L induced a significant apoptosis in HepG2,BGC-823,MCF-7 cells（P〈0.001） and the effect was dose-dependent.The activities and protein expressions of Caspase3,Caspase9 were up-regulated in HepG2,BGC-823,MCF-7 cells（P〈0.001）;Capase8 was up-regulated at protein level in BGC-823 cells lightly,but it did not show any difference in HepG2 and MCF-7 cells（P〉0.05）.The apoptosis rates of cancer cells treated with VPA and specific inhibitors of Caspase3,Caspase9 together was lower than in the groups with VPA treatment singlely（P〈0.005）,thus indicationg that the activities of Caspase3,Caspase9 which had been activated by VPA were blocked by the specific inhibitors of Caspase3 and Caspase9.The apoptosis rate of the cells treated with VPA and Caspase8 specific inhibitor remained the same as the treated by VPA only,hence it was verified that Caspase8 activation did not play an important role in apoptosis induction by VPA in HepG2,BGC-823,MCF-7 cells.Conclusion：Modification of histone acetylizad level with VPA can regulate Caspase3,Caspase9 expressions obviously;To Caspase8,it show some difference according to the histogenesis and phenotypes of different carcinoma types.Up-regulation of the activities and protein expressions of Caspase3,Caspase9 may be the main pathway in apopt

关 键 词：组蛋白 组蛋白脱乙酰酶抑制剂 丙戊酸钠 肝癌 胃癌 乳腺癌 细胞凋亡 Caspase调控 

分 类 号：R392.12[医药卫生—免疫学] R73-34[医药卫生—基础医学]