辛二酰苯胺异羟肟酸对结肠癌HCT116和SW480细胞增殖、周期和凋亡的影响

Effects of suberoylanilide hydroxamic acid on proliferation, cell cycle and apoptosis of colon cancer HCT116 and SW480 cells

目的:研究辛二酰苯胺异羟肟酸(suberoylanilide hydroxamic acid,SAHA)对结肠癌细胞系HCT116和SW480增殖、周期和凋亡的影响,并对其分子作用机制进行初步探讨。方法:将不同浓度SAHA分别处理结肠癌HCT116和SW480细胞后,MTT法检测SAHA对HCT116和SW480细胞增殖的影响,流式细胞仪检测HCT116和SW480细胞周期和细胞凋亡率,罗丹明(rhodamine)123和二氯二氢荧光素二乙酸酯(DCFH-DA)法检测HCT116和SW480细胞线粒体跨膜电位(ΔΨm)和活性氧(ROS)水平,Real-time PCR和Western blotting法检测乙酰化组蛋白3(Ac-H3)、p21、Cyclin D1、Bax和Bcl-2的mRNA和蛋白的表达水平。结果:SAHA作用于HCT116和SW480细胞48 h后,细胞增殖被抑制、细胞周期G1期比率升高、凋亡率升高(均P<0.05),线粒体跨膜电位显著下降、细胞内ROS产生增多(均P<0.05)。与对照组比较,SAHA处理组p21和Bax mRNA增多、Cyclin D1和Bcl-2 mRNA表达量减少(均P<0.05),相关蛋白Ac-H3、p21和Bax增多,Cyclin D1和Bcl-2减少(均P<0.05)。结论:SAHA抑制结肠癌HCT116和SW480细胞增殖、阻滞细胞周期并诱导细胞凋亡,其机可能与调节p21、Cyclin D1和Bcl-2家族基因的表达、促进组蛋白乙酰化有关。

Objective： To investigate the effects and molecular mechanisms of Suberoylanilide Hydroxamic Acid （SAHA） on the proliferation, cell cycle and apoptosis of colon cancer HCT116 and SW480 cells. Methods： Colon cancer cells （HCTll6 and SW480） were treated with a series of concentrations of SAHA. MTT assay was em- ployed to evaluate the effect of SAHA on proliferation of HCT116 and SW480 cells. The cell cycle distribution and apoptosis were determined by flow cytometry. Rhodamine 123 and DCFH-DA were applied to detect the mito- chondrial membrane potential（ A qs m） and reactive oxygen species （ROS） production. Reverse transcription poly- merase chain reaction （RT-PCR） and Western blotting were used to assess the mRNA and protein expressions of Ac- H3, p21, Cyclin D1, Bax and Bcl-2. Results： After 48 h of SAHA treatment on HCTll6 and SW480 cells, the cell proliferation was inhibited, the G1 phase ratio of cells and the apoptosis rate was increased （all P〈0.05）; moreover, SAHA also reduced A^m and increased cellular ROS production （all P〈0.05）. Compared with control group, the mRNA expressions of p21 and Bax were higher in SAHA group, while the mRNA expressions of CyclinD1 and Bcl- 2 were lower （all P〈0.05）; Furthermore, the protein expressions ofAc-H3, p21 and Bax were improved, while the protein expressions of CyclinD1 and Bcl-2 were decreased in SAHA group （all P〈0.05）. Conclusion： SAHA may suppress cell growth, induce apoptosis and cause cell cycle arrest of colon cancer cells by promoting histone acetyla- tion and modulating their related genes of p21, CyclinD1 and Bcl-2 family.