冬凌草甲素通过调控miRNA-125a诱导肝癌细胞HepG2凋亡的研究

Study on oridonin inducing apoptosis of HepG2 cell via regulating miRNA-125a pathway

目的探讨冬凌草甲素通过调控微小核糖核酸125a(RNA-125a)诱导肝癌细胞Hep G2凋亡以及相关机制。方法冬凌草甲素(10,20,30,40,50,70,100μmol·L-1)处理Hep G2肝癌细胞24 h,用MTT法测定细胞的增殖情况;用Hoechst 33342染色检测细胞形态改变;用实时定量荧光PCR(real-time PCR)检测miRNA-125a与血管内皮生长因子(VEGF)mRNA表达,免疫细胞化学法检测VEGF蛋白表达。结果冬凌草甲素能浓度依赖性地抑制Hep G2细胞的增殖(P<0.05),Hep G2细胞核形态明显改变;Hep G2细胞经冬凌草甲素作用24h后,miRNA-125a表达上调,而VEGF mRNA表达下调(P<0.05);而高剂量冬凌草促进miRNA-125a表达以及抑制VEGF表达的作用最显著(P<0.01)。结论冬凌草甲素可通过上调miRNA-125a,使VEGF表达减少,而诱导肝癌细胞Hep G2凋亡。

Objective To investigate possible mechanism of oridonin inducing apoptosis of Hep G2 cells via regulating miRNA- 125 a. Methods Hep G2 cells were treated with oridonin（ 10,20,30,40,50,70,100μmol · L- 1） for 24 h and the cell viability was measured with MTT assay. Morphological change of cell nucleus was detected with Hoechst33342 staining. The expression of miRNA- 125 a and vascular endothelial growth factor（ VEGF） mRNA and protein were detected by real- time PCR and immunocytochemistry method. Results Oridonin could suppress the proliferation of Hep G2 with concentration dependence（ P〈 0. 05）, and Hep G2 nuclear shape changed. With oridonin treating Hep G2 for 24 h,the expression of miRNA- 125 a level up- regulated,while the expression of VEGF mRNA level down- regulated,and the difference between two groups was statistically significant（ P〈 0. 05）.And the high- dose oridonin promote the miRNA- 125 a expressing and inhibited expression of VEGF more significantly than the low- dose（ P〈 0. 01）. Conclusion Oridonin can induce apoptosis of Hep G2 cell,and possible mechanism may be up- regulating miRNA- 125 a to down-regulate expression of VEGF.