姜黄素对乳腺癌细胞SK-BR-3甲基化的影响及其机制的研究

Effects of Curcumin on DNA methylationof breast cancer cell SK-BR-3 and its mechanism

目的:观察姜黄素对乳腺癌细胞SK-BR-3甲基化水平的影响,并探讨其机制。方法:将SK-BR-3细胞随机分成四组,对照组加入等体积PBS(姜黄素浓度为0μg/ml),三组观察组分别为姜黄素低剂量组(1.25μg/ml)、中剂量组(2.5μg/ml)、高剂量组(5.0μg/ml)。克隆形成抑制试验分析细胞克隆形成能力;荧光显微镜观察细胞甲基化水平变化;荧光定量PCR检测B淋巴细胞瘤-2基因(B-cell lymphoma-2,BCL-2)、TET1、TET2和DNA甲基转移酶3b(DNA methyltransferases,DNMT3b)的mRNA转录变化。结果:与对照组细胞克隆形成率相比,三组观察组的细胞克隆形成率均明显下降,比较差异有统计学意义(P<0.05);随着姜黄素浓度的升高,SK-BR-3细胞基因组甲基化水平明显下降,DNMT3b的mRNA转录量明显下调,TET1与BCL-2的转录量明显上调,比较差异有统计学意义(P<0.05)。结论:姜黄素在体外可以通过改变DNMT3b与TET1的转录影响DNA甲基化水平并抑制乳腺癌细胞SK-BR-3克隆形成能力。

Objective： To evaluate effects of Curcumin on DNA methylation of breast cancer cell SK-BR-3 and to explore its mechanism.Methods： The SK-BR-3 cells was divided into four groups,wherein the control group was treated with the same volume PBS （the concentration of Curcuminis 0 μg/ml）,while other groups were treated with different concentrations of Curcumin （5.0μg/ml,2.5μg/ml,1.25μg/ml,observation groups： low dose group,medium dose group and high dose group）,separately.The inhibition on colonel formation ability of SK-BR-3 was estimated with colonel formation test; the DNA methylation level was detected with 5mC antibody labelled with FITC; and the mRNA expression of BCL-2,TET1,TET2 and DNMT3b were detected with real-time PCR.Results： Compare with the control group,the colony formation rates of the three observation groups were significantly reduced,and the differences among the three observation groups and the control group were statistically significant （P〈 0.05）.With the increase of the concentration of Curcumin,the level of DNA methylation decreased significantly,the mRNA expression of DNMT3b decreased significantly,but the expressions of TET1 and BCL-2 increased greatly,and the differences were statistically significant （P0.05）.Conclusions： Curcumin could inhibitsthe DNA methylation and the colony formation ability of SK-BR-3 cells through changing the expression of DNMT3b,TET1 and BCL-2.