中文摘要：

目的：探讨山奈酚（kaempferol）对人胃癌MGC-803细胞的生长抑制作用,以及诱导细胞凋亡和对细胞周期的影响。方法：采用MTT法检测细胞存活率;DAPI染色法观察细胞的凋亡形态;彗星电泳技术和FCM检测不同浓度山奈酚对细胞中DNA的影响。结果：山奈酚体外能明显抑制人胃癌MGC-803细胞的增殖。用不同浓度（6.25、12.5、25、50和100μmol/L）的山奈酚处理MGC-803细胞72h后,细胞的生长抑制率分别为10.32%、13.95%、21.58%、35.18%和58.13%,各药物处理组与对照组比较,P值均〈0.01,呈剂量效应关系。50和100μmol/L山奈酚分别作用细胞24、48、72和96h后,结果显示药物作用的时间越长,对细胞的抑制作用越强,呈时间效应关系。DAPI染色结果显示,不同浓度药物组的细胞均有明显的细胞凋亡特征。30、60和120μmol/L山奈酚作用于细胞72h后,彗星电泳检测结果显示细胞后面均呈现拖尾现象,细胞头部平均光密度值较阴性对照组降低,彗星尾距较阴性对照组增加,各药物组与对照组比较,P值均〈0.01,且与药物浓度呈相关性。FCM检测结果显示,浓度为30、60和120μmol/L的山奈酚作用于细胞72h后,出现亚二倍体凋亡峰,细胞周期被阻滞于S期和G2/M期,各药物组凋亡率较阴性对照组均明显升高。结论：山奈酚能抑制人胃癌细胞MGC-803的增殖并诱导其凋亡。

英文摘要：

Objective：To study the effect of kaempferol on proliferation, apoptosis, and cell cycle distribution of human gastric cancer cell line MGC-803.Methods：MTT assay was used to detect the viability of MGC-803 cells. DAPI staining, comet assay, and flow cytometry were used to observe the effect of different concentrations of kaempferol on DNA levels of MGC-803 cells, respectively.Results：After 72 h treatment with kaempferol at 6.25, 12.5, 25, 50 and 100 μmol/L, the growth inhibition rate of MGC-803 cells reached 10.32%, 13.95%, 21.58%, 35.18% and 58.13%, respectively. The effect was in a dose-dependent manner. The diffe-rence was significant between kaempferol treatment group and control group （P〈0.01）. Kaempferol 50 and 100 μmol/L inhibited the growth of MGC-803 cells in a time-dependent manner at 24, 48, 72, and 96 h. DAPI staining showed that MGC-803 cells displayed the characteristics of apoptosis after kaempferol treatment at different concentrations. Comet assay showed that MGC-803 cells had ＂smearing＂ phenomenonin after kaempferol 30, 60 and 120 μmol/L treatment, and the average optical density declined and migration distance of DNA increased compared with negative control （all P〈0.01）. The effect of kaempferol was in a concentration-dependent manner. The flow cytometry assay illustrated that there was a subdiploid apoptotic peak in each group after 72 h treatment with keampferol 30, 60 and 120 μmol/L, and the cells were arrested at the S and G2/M phases, the apoptotic rate increased significantly compared with control group. Conclusion：Kaempferol inhibits the apoptosis and induces apoptosis of human gastric cancer cell line MGC-803.