柴胡皂苷D通过诱导自噬抑制人结直肠癌细胞SW480增殖的实验

目的:研究柴胡皂苷D（saikosaponin-D，SSD）对人结直肠癌细胞SW480自噬的影响，并探讨诱导的自噬对细胞增殖的影响。方法:Western-blot检测SSD对自噬相关蛋白LC3A/B和p62表达的影响，LC3翻转实验和GFP-RFP-LC3荧光实验验证自噬流的发生。Western-blot检测3-MA对SSD所诱导自噬的抑制作用，MTT和细胞计数实验研究3-MA抑制自噬后SSD对SW480细胞增殖的影响。结果:SSD能够诱导SW480细胞发生自噬，表现在LC3A/B II及LC3A/B II/I比值的增高、自噬经典底物蛋白p62的减少、LC3翻转试验阳性以及LC3荧光实验中黄色和红色荧光颗粒的增多（P＜0.05）。自噬抑制剂3-MA能够抑制SSD所诱导自噬的发生（P＜0.05），且3-MA抑制自噬后，SSD对SW480的增殖抑制效应减弱（P＜0.05），提示SSD诱导的自噬对细胞的增殖起抑制作用。结论:SSD通过诱导自噬抑制人结直肠癌细胞SW480的增殖。

Saikosaponin-D inhibits the proliferation of colorectal cancer cell line SW480 by inducing autophagy:An experimental study

Objective:To study the impacts of saikosaponin-D (SSD) on autophagy induction in human colorectal cancer cell line SW480 and further explore its influence towards cell proliferation.Methods:Using Western-blot to check the impacts of SSD on the expression of autophagy related proteins LC3A/B and p62.Performing LC3 turnover assay and GFP-RFP-LC3 fluorescent assay to check autophagy flux.Using Western-blot to check the autophagy inhibition effect of 3-MA on SSD.Utilizing MTT assay and cell counting assay to check the influence of SSD on cell proliferation within autophagy inhibition by 3-MA.Results:Autophagy was induced by SSD in SW480 because of the increase of LC3A/B II and LC3A/B II/I ratio,the decrease of classic autophagy substrate p62,positive LC3 turnover assay and the increase of yellow and red dots in GFP-RFP-LC3 fluorescent assay (P＜0.05).3-MA inhibited SSD induced autophagy (P＜0.05).When autophagy was inhibited by 3-MA,SSD's proliferation inhibition ability on SW480 was attenuated (P＜0.05).Conclusion:SSD inhibits the proliferation of SW480 by inducing autophagy.