BIX-01294对肝癌细胞周期、凋亡及移植瘤的影响

目的:探究组蛋白甲基转移酶G9a抑制剂(BIX-01294)对肝癌细胞周期、凋亡及移植瘤的影响。方法:将SMMC-7721、BEL-7402、HL-7702原始细胞株传代培养后,分为空白对照组和不同浓度(1μM、5μM、10μM、20μM)BIX-01294处理组。应用Western-blot法检测G9a及肝癌细胞内凋亡蛋白CC3、C-PARP、Bax、Bcl-2表达水平;应用四甲基偶氮唑盐(MTT)比色法检测不同浓度BIX-01294处理SMMC-7721、BEL-7402细胞24、48、72、96 h后的细胞增殖情况;应用流式细胞术检测不同浓度的BIX-01294处理肝癌细胞96h后细胞周期分布情况;移植瘤试验21 d后测量裸鼠体内肿瘤体积及重量,并检测瘤体内H3K9me2的蛋白水平。结果:G9a在肝癌细胞SMMC-7721、BEL-7402中表达水平高于HL-7702细胞(P<0.05)。不同浓度的BIX-01294对SMMC-7721细胞和BEL-7402细胞增殖具有抑制作用,且具有时间依赖性和剂量依赖性(均P<0.05)。不同浓度BIX-01294处理细胞96h后,SMMC-7721细胞和BEL-7402细胞G0/G1期细胞比例增加,S和G₂/M期的细胞比例降低(P<0.05)。5μM BIX-01294处理细胞96h后能明显增加CC3、Bax、C-PARP表达水平,并降低Bcl-2的表达水平(P<0.05),与空白对照组相比,BIX-01294处理组裸鼠肿瘤体积减小,重量较低,且肿瘤组织内H3K9me2的表达水平下降(P<0.05)。结论:BIX-01294导致SMMC-7721、BEL-7402细胞发生周期阻滞和凋亡,且对肿瘤的生长具有明显的抑制作用,其可能是通过抑制G9a的表达从而降低H3K9me2的表达来抑制肿瘤的生长。

Effect of BIX-01294 on Cell Cycle, Apoptosis and Transplanted Tumor of Hepatocarcinoma

Objective:To investigate the effect of Inhibitors of protein methyltransferase G9 a(BIX-01294)on the cell cycle,apoptosis and transplanted tumor.Methods:SMMC-7721,BEL-7402,HL-7702 cell lines were subcultured and divided into blank control group and BIX-01294 treatment group with different concentrations(1μM,5μM,10μM,20μM).Western blot was used to detect the expression level of G9 a and apoptosis protein CC3,C-PARP,Bax,Bcl-2.The proliferation of SMMC-7721 and BEL-7402 cells treated with BIX-01294 at different concentrations for 24,48,72 and 96 hours was detected by Tetramethylazozolium salt(MTT)colorimetry;the cell cycle distribution of hepatoma cells treated with different concentrations of BIX-01294 for 96 hours were examined by flow cytometry;the tumor volume,weight,the protein level of H3 K9 me2 were measured 21 days after tumor transplantation experiment in nude mice.Results:The expression level of G9 a in SMMC-7721 and BEL-7402 cell were higher than HL-7702 cell(P<0.05).Various concentrations of BIX-01294 could inhibit SMMC-7721 cell and BEL-7402 cell proliferation in a time-dependent and dose-dependent manner(P<0.05).There is a significant difference in cell cycle distribution with increased G0/G1 phage cell percentage,reduced S and G₂/M phage cell percentage at 96 h by BIX-01294 treated(P<0.05).The expression levels of CC3,Bax,C-PARP were significantly increased,and the Bcl-2 level were significantly reduced at 96 h by 5μM BIX-01294 treated(P<0.05).Compared with the blank control group,the tumor volume and weight of the bix-01294 treated group decreased,and the expression level of H3 K9 me2 in tumor tissue decreased(P<0.05).Conclusion:BIX-01294 leads to cell cycle arrest and apoptosis of SMMC-7721 and BEL-7402 cells,and has a significant inhibitory effect on tumor growth.It may be through inhibiting the expression of G9 a to reduce the expression of H3 K9 me2 to inhibit tumor growth.