芦竹素对人前列腺癌细胞系细胞凋亡及bcl-2/bax表达的影响

Effects of Arundoin on Cell Apoptosis and Expression of Bcl-2/Bax in Prostate Cancer Cells

目的:研究芦竹素对人前列腺癌细胞系LNCap细胞凋亡的影响及其作用机理。方法:取对数生长期的LNCap细胞,分别用不同浓度的芦竹素处理48 h后,用MTT细胞增殖法检测细胞活力,Hoechst染色观察细胞形态学变化,流式细胞仪检测细胞凋亡和周期,并用Western blot检测LNCap细胞中Bcl-2和casepase家族蛋白表达情况。结果:芦竹素能以剂量依赖性方式降低LNCap细胞的活力,浓度为20、40、80μg/m L的芦竹素作用LNCap细胞48 h后,细胞凋亡率分别增加至11.3%、25.2%、57.1%,明显高于对照组(0.5%);不同浓度的芦竹素处理LNCa P细胞48 h后,G0/G1期细胞的比例增加,而G2/M期和S期的比例减少;芦竹素处理组LNCap细胞Cleaved-caspase 3及Cleaved-caspase 9表达量增加,同时促凋亡蛋白Bax表达量增加,而抗凋亡蛋白Bcl-2表达量降低,且呈剂量依赖性。结论:芦竹素能抑制LNCap细胞增殖并诱导其凋亡,其作用机制与上调Cleaved-Csepase 3,Cleaved-Casepase 9和Bax表达、下调Bcl-2的表达有关。

Objective To explore the effect of arundoin on cell apoptosis in human prostate cancer LNCap cells and the mechanism. Methods LNCap cells were treated with arundoin in different concentration. The relative cell viabilities were determined by the MTT method, the morphological changes of cells were observed using Hoechst 33258 staining, and the apoptosis and cell cycle were analyzed by flow cytometry. At the same time, the protein expressions of Bcl-2, Bax, caspase-3 and caspase-9 were detected by Western blot. Resuits Arundoin （20-120 μg/mL） significantly inhibited the viabilities of LNCap cells in a dose-dependent man- ner. Hoechst 33258 staining showed that arundoin increased the membrane permeability of LNCap cells. Flow cy- tometry results showed that arundoin could induce apoptosis in LNCap ceils, the apoptotic ratios were 11.3% （20 μg/mL）, 25.2% （40 μg/mL）, 57.1% （80μg/mL）, significantly higher than that of control grouP〈0.5% （0 μg/mL）. After different concentrations of arnndoin treatment for 48 h, the proportion of LNCap cells in GO/G1 phase was increased, while the proportion of the G2/M phase and S phase were reduced. In 80 μg/mL arundoin treatment group, the proportion of cells in G0/G1 phase was increased significantly. The data of Western blot showed that arundoin （20, 40, 80μg/mL） up-regulated the expression levels of cleaved caspase-3, cleaved caspase-9, and Bax, but down-regulated Bcl-2, in a dose-dependent manner. Conclusion Arnndoin could inhibit the prolif- eration of LNCap cells and promote apoptosis, which may be associated with the down regulation of Bcl-2 ex- pression and up regulation of Bax expression, as well as the increase of relative activity of caspases.