Quercetin调节肝癌HepG2细胞PTEN基因表达诱导细胞凋亡的实验研究

Study on quercetin for regulating HepG2 cellular PTEN gene expression and inducing cellular apoptosis

目的探讨三磷酸肌醇(IP3)和PTEN基因表达变化在quercetin诱导肝癌细胞凋亡中的作用。方法以肝癌HepG2细胞为空白对照,以不同浓度quercetin作用于HepG2细胞不同时间后,应用同位素试剂盒检测细胞IP3含量,RT-PCR分析PTENmRNA表达,Western blotting分析细胞PTEN蛋白表达,流式细胞仪检测细胞凋亡率。结果各浓度的quercetin作用于肝癌HepG2细胞,IP3含量显著低于对照组(17.9±1.5、15.5±1.1、5.7±0.9、5.5±0.8vs29.4±0.5),PTENmRNA表达与对照组无显著差异,PTEN蛋白表达显著高于对照组(0.55±0.02、0.67±0.02、0.94±0.04、0.95±0.03vs0.02±0.002),细胞凋亡率显著高于对照组。60μmol/Lquercetin作用于肝癌HepG2细胞6h、12h、24h、48h、72h,各时相IP3含量显著低于对照组(23.3±1.4、12.0±1.4、7.5±0.8、5.6±0.5、4.3±0.6vs29.2±0.6,P<0.01)。PTENmRNA表达与对照组无显著差异,12h后各时项PTEN蛋白表达显著高于对照组,24h后各时相细胞凋亡率为显著高于对照组(P<0.01)。结论Quercetin能减少IP3生成,上调PTEN蛋白,诱导肝癌细胞凋亡。

Objective To explore the role of 1,4,5-trisphosphate inositol （IP3） and PTEN gene expression in apoptosis of HepG2 cells induced by quercetin. Methods With HepG2 cells of liver cancer as blank control and using different concentration of quercetin after treating HepG2 cells in different time, cellular IP3 content,RT-PCR analyzed PTEN mRNA expression,western blotting analyzed cellular PTEN proein expression were detected with isotopic kit and cellular apoptosie rate were detected wtih flow cytometry. Results When different concentration of quercetin was effected on HepG2 cells of liver cancer, the IP3 content was lower than that control group significantly. PTEN mRNA expression was no significant difference between two groups. PTEN protein expressio was higher than that control group significantly. The cellualr apoptostic rate was higher than that control group significanhy. In the quercetin concentration of 60 μmol/L was effeeted on HepG2 cells in 6,12,24, 48, and 72 hours, the IP3 content of different phase was lower than that control qroup significantly. PTEN mRNA was no significant difference compared with control group. After 12 hours,each phase PTEN protein expression was higher than that control group sigificantly（P〈0.01 ） and after 24 hours, each phase cellular apoptostic rate was higher than that control group significanhy （P〈0.01）. Conclusion Quercetin would reduce IP3 formation and it may up-regulate PTEN protein and induce cellular apoptosis of liver cancer.