目的 探讨二氢杨梅素（DMY）对肺癌A549细胞的诱导凋亡作用。方法 以肺癌A549细胞为研究对象，采用MTT法研究DMY对A549细胞的抗肿瘤作用，并进一步通过流式细胞术检测DMY对A549细胞的凋亡作用，免疫印迹法（Western blotting）检测促凋亡因子Bax和抗凋亡因子Bcl-2表达水平，进一步探讨其机制。
结果 DMY浓度越大，对A549细胞的抑制作用越明显，48h的IC50为64.45g/L；流式细胞术显示，随着DMY浓度的增加A549细胞凋亡也逐渐增加；Western blotting结果显示，DMY可诱导A549细胞中凋亡因子Bax蛋白表达增加，同时抗凋亡因子Bcl-2蛋白表达减少，尤其高浓度组改变明显。
结论 DMY可以在体外诱导A549细胞凋亡。

Objective To study the effect of dihydromyricetin on apoptosis of hunman nonsmall cell lung cancer A549 cells, and to explore new drugs for lung cancer.
Methods A549 cells were treated with various concentrations of dihydromyricetin for 48hours. MTT assay was used to determined the proliferation ability of A549 cells, flow cytometry was used to detect the influence of dihydromyricetin on the cell apoptosis of A549 cells, Western blotting analysis was used to evaluate the levels of Bax, Bcl-2 expressions. Results MTT assay results showed a significant inhibition in A549 cells with a dose-dependent manner, when compared with control cells, the inhibitory concentration for 50%（IC50）was 64.45mg/L at 48 hours; Flow cytometry showed that dihydromyricetin induced apoptosis of A549 cells in a dose-dependent manner as well. Further analysis by Western blotting showed that the expression of Bax was increased, while the expression of Bcl-2 was reduced when A549 cells was incubated for 48 hours with dihydromyricetin. Conclusion Dihydromyricetin plays a role of anti-tumor through inhibiting A549 cells proliferation and inducing apoptosis.