槲皮素对人肺癌细胞株A-549细胞增殖的抑制作用

目的：观察槲皮素对人肺癌细胞株A-549细胞增殖和凋亡的影响。方法以不同浓度槲皮素培养人肺腺癌细胞株A-549细胞后，采用MTT法检测槲皮素对细胞增殖的影响；流式细胞仪检测细胞周期和细胞凋亡变化；通过倒置显微镜、Heochst33258荧光染色、透射电镜观察凋亡细胞的形态学改变；Western blot方法检测凋亡抑制蛋白Survivin的表达情况。结果不同浓度槲皮素作用于人肺腺癌细胞株A-549细胞24h后，细胞存活率显著降低，且与剂量呈依赖关系。15、30、60μmol/L的槲皮素作用于人肺腺癌细胞株A-549细胞24h后，细胞阻滞发生在G2/M期；凋亡率分别为（7.24±1.73）%、（12.57±2.7）%和（26.02±1.67）%，与浓度为0的凋亡率（2.67±2.32）%]比较，差异均有统计学意义（均P＜0.01）；从形态学上观察到肺癌细胞发生凋亡或坏死。通过Western blot检测发现，随着槲皮素作用浓度的增加Survivin蛋白的表达逐渐降低。结论槲皮素对人肺癌细胞株A-549细胞株有抑制其增殖及诱导凋亡的作用，其机制可能与细胞周期阻滞及抑制凋亡抑制蛋白Survivin的表达有关。

Quercetin inhibits proliferation and induces apoptosis of human lung cancer A-549 Cells in vitro

Objective To investigate the effect of quercetin on proliferation and apoptosis of human lung cancer cellline A- 549 in vitro. Methods The cultured A- 549 cells were treated with different concentrations of quercetin, and cellproliferation and apoptosis were detected by MTT and flow cytometry, respectively. The morphological changes of the apoptotic cells were observed by invert microscopy, transmission electron microscopy and Heochst33258 fluorescence staining. The expression of survivin was analyzed by Western blot. Results After treatment of quercetin for 24 h the proliferation of A- 549 cells was inhibited in a dose- dependent manner, and cells were arrested at the G2/M phase. The apoptosis rates of quercetin treatment groups （15, 30, 60μmol/L） were（7.24＆#177;1.73）%, （12.57＆#177;2.72）%and （26.02＆#177;1.67）%, respectively, significantly higher than that of control group （2.67＆#177;2.32）%, P＆lt;0.01]. Apoptosis or necrosis of A- 549 cells were morphological y observed after quercetin treatment for 24h. The expression of survivin protein in quercetin- treated A- 549 cells was decreased in a dose- dependent manner. Conclusion Quercetin can inhibit proliferation and induce apoptosis of human lung cancer A- 549 cells, which is associated with cellcycle ar-rest and down- regulation of survivin expression.