中文摘要：

目的：评价白花丹素对黑素瘤细胞体外增殖及凋亡的影响。方法：体外培养黑素瘤细胞A375细胞株，应用不同浓度的白花丹素进行处理，培养24h后，MTT法测定对细胞增殖的影响；用流式细胞术检测细胞的凋亡率；Western blot检测bcl-2的表达。结果：浓度为1～13μmol／L的白花丹素能显著抑制A375细胞株的增殖，且随浓度增加抑制作用递增；白花丹素作用24h的半数抑制浓度约为10μmol／L；当浓度为2．5μmol／L、5．0μmol／L和10．0μmol／L作用24h，细胞的凋亡率分别为8．52％±0．96％、14．83％±1．34％和19．56％±1．85％，与空白对照组（4．58％±0．46％）比较差异有统计学意义（P〈0．05）；细胞内bcl-2蛋白表达量随药物浓度升高而递减，与对照组比较差异有统计学意义（P〈0．05）。结论：白花丹素体外能抑制黑素瘤细胞增殖，并诱导细胞凋亡及下调黑素瘤细胞bcl-2蛋白的表达。

英文摘要：

Objective： To assess the effects of plumbagin on proliferation and apoptosis of human melanoma cell A375 in vitro. Methods： Human melanoma cell A375 was cultured and treated with plumbagin in different concentrations for 24 h. Cell proliferation was determined by MTT assay, apoptosis by/low cytometry. The expression of bcl - 2 was detected by Western blot. Results： Compared with blank control group, plumbagin （at concentration of 1 - 13 μmol/L） significantly inhibited the proliferation of tumor cells in a dose - dependent manner （ P 〈 0.05）. After treated with plumbagin for 24 h, the apoptosis rate was 8.52%±0.96%, 14.83%±1.34% and 19.56%±1.85% at 2.5 μmol/L, 5.0 μmol/L and 10.0 μmol/L of plumbagin, respectively, when compared to 4.58%±0.46% in untreated cells （ P 〈 0.05）. The expression of bcl - 2 protein was down - regulated in plumbagin - treated groups compared with blank control group （P 〈 0.05）, with a negative dose-dependent manner. Conclusion： Plumbagin can induce cell apeptosis, down - regulate the expression of bcl - 2 and inhibit the proliferation of human melanoma A375 cells.