【摘要】 目的:分析丁酸钠对HT-29结肠癌细胞p53三个主要靶基因(p21waf1,bax和gadd45)的调控,并探讨其作用机制。方法:HT-29细胞常规培养在含有和不含有丁酸钠的培养液中。分别用MTT和流式细胞仪(flow cytometry,FCM)检测细胞增殖和细胞周期分布,通过形态学观察、亚G1峰的检测和AnnexinV-FITC双标记观察细胞凋亡情况;RT-PCR和Western blot分别检测丁酸钠对p21waf1,bax和gadd45三种基因mRNA和蛋白表达水平的影响。结果:丁酸钠以剂量和时间依赖的方式抑制HT-29细胞增殖和诱导凋亡,并阻滞细胞于G1期。RT-PCR和Western blot结果显示丁酸钠可以促进p21waf1和bax基因mRNA和蛋白的表达,而对gadd45基因的表达无明显影响。结论:2.5mmol/L以上浓度的丁酸钠可以抑制HT-29细胞增殖并诱导凋亡,该作用可能通过上调p21waf1和bax基因表达而实现。更多还原

【Abstract】 Objective:To investigate the regulatory effects of sodium butyrate on p53 target genes(p21waf1,bax,and gadd45)in HT-29 colorectal cancer cells and the related mechanisms.Methods:HT-29 cells were cultured in the absence or presence of sodium butyrate.The cell proliferation and cell cycle were studied by MTT and FCM,respectively.Apoptosis was assessed by observing cell morphology,percentage of sub-G_ 1 cells and AnnexinV-FITC.The effects of sodium butyrate on transcription of p21waf1,bax and gadd45 were analyzed by RT-PCR and Western blot.Results:Sodium butyrate inhibited proliferation and induced apoptosis of HT-29 cells in a time-and dose-dependent manner,and it blocked HT-29 cell at G_ 1 phase.Sodium butyrate stimulated p21waf1 and bax expression both at mRNA and protein level in HT-29 cells,but had little effect on the transcription of gadd45.Conclusion:Sodium butyrate can inhibit proliferation and induce apoptosis of HT-29 cells,which might be through up-regulating p21waf1 and bax expression both at mRNA and protein levels.更多还原