香叶木素诱导人肝癌HepG2细胞凋亡及周期阻滞的机制研究

目的 研究香叶木素对人肝癌HepG2细胞的增殖、凋亡及周期阻滞的影响并揭示其分子机制.方法 MTT方法检测不同浓度香叶木素对肝癌HepG2的细胞活力的影响;流式细胞术检测不同浓度香叶木素处理对HepG2细胞周期阻滞及细胞凋亡的作用;Western blot检测香叶木素处理对细胞p53、Bcl-2、Bax、Cleaved-cas-pase3、Cleaved-caspase8、Cleaved-PARP、Bak、cdc2、cyclinB1、p21等细胞周期调节或细胞凋亡相关蛋白表达的调节.结果 香叶木素能显著抑制人肝癌HepG2细胞的增殖并且诱导细胞凋亡(P<0.05);流式细胞术对细胞周期检测示:香叶木素处理HepG2细胞,使G0/G1期细胞比例显著降低,而G2/M期细胞比例显著升高(P<0.05).香叶木素可下调HepG2细胞中抗凋亡蛋白Bcl-2、cdc2、cyclinB1的蛋白表达,上调p53、p21、Bax、Bak,Cleaved-caspase3、Cleaved-caspase8、Cleaved-PARP等促凋亡蛋白.结论 香叶木素在体外实验能通过激活p53/Bcl-2细胞凋亡通路抑制人肝癌HepG2细胞的增殖及促进细胞凋亡,同时通过上调p53、p21下调cdc2、cyclinB1诱导细胞G2/M周期阻滞.

Promoting effect of Diosmetin on the cell cycle arrest and cell apoptosis in HepG2 cell and its mechanism

Objective To study the effect of Diosmetin on cell proliferation, cell apoptosis and cell cycle ar-rest in human hepatocellular carcinoma HepG2 cells, and dissect the underlying mechanism. Methods MTT assay was performed to detect the viability of HepG2 cells under different levels of Diosmetin. The cell apoptosis rate and cell cy-cle arrest were analyzed by flow cytometry (FCM). Western blot was applied to measure the protein levels of P53, Bcl-2, Bax, Cleaved-caspase3, Cleaved-caspase8, Cleaved-PARP, Bak, cdc2, cyclinB1, P21. Results Diosmetin treat-ment on HepG2 cells significantly inhibited cell proliferation and induced cell apoptosis (P<0.05). FCM results showed that Diosmetin treatment significantly promoted cell cycle arrest in G2/M phase in HepG2 cells (P<0.05), with the pro-portion of cells in G0/G1 phase significantly reduced. Besides, Diosmetin significantly downregulates Bcl-2, cdc2, cy-clinB1, and up-regulated Bax, Cleaved-caspase3, Cleaved-caspase8, Cleaved-PARP, Bak, P53, P21. Conclusion Dios-metin inhibits HepG2 cell proliferation and induces cell apoptosis by activation of p53/Bcl-2 pathway. Meanwhile, Dios-metin treatment induces G2/M cell cycle arrest in HepG2 cell by down-regulation of cell cycle related protein cdc2, cy-clinB1 and up-regulation of P53, P21.