木犀草素对人脉络膜黑色素瘤细胞株C918血管生成拟态形成的影响

Inhibitory effects of luteolin on vasculogenic mimicry in human choroidal melanoma cell line C918

目的探讨木犀草素对人脉络膜黑色素瘤细胞株C918血管生成拟态形成的影响及其可能的分子机制。方法体外培养C918细胞,木犀草素0μmol·L^-1、0.10μmol·L^-1、6.25μmol·L^-1、12.50μmol·L^-1、25.00μmol·L^-1、50.00μmol·L^-1、100.00μmol·L^-1、200.00μmol·L^-1、400.00μmol·L^-1作用细胞12 h、24 h后,CCK-8法测定光密度值,通过GraphPad Prism软件拟合量效曲线。根据IC50值及实验目的,确定分组为对照组(木犀草素0μmol·L^-1组)、木犀草素12.50μmol·L^-1组、木犀草素25.00μmol·L^-1组、木犀草素50.00μmol·L^-1组。应用划痕实验和Transwell侵袭实验检测各组细胞迁移、侵袭能力。在Matrigel基质胶上三维培养C918细胞并行PAS染色,显微镜下观察各组细胞血管生成拟态形成情况。Western blot检测p-PI3K P85、AKT、p-AKT蛋白表达。结果CCK-8实验结果显示,木犀草素呈浓度依赖性和时间依赖性抑制C918细胞活力,GraphPad Prism软件拟合量效曲线,确定木犀草素作用C918细胞12 h及24 h的IC50值分别为163.70μmol·L^-1和51.46μmol·L^-1。划痕实验及Transwell细胞侵袭实验结果显示,各浓度木犀草素组细胞迁移速率、侵袭能力均明显低于对照组,差异有统计学意义(均为P<0.001);木犀草素12.50μmol·L^-1组和木犀草素25.00μmol·L^-1组相比,细胞迁移速率差异无统计学意义(P>0.05);木犀草素25.00μmol·L^-1组和木犀草素50.00μmol·L^-1组相比,细胞侵袭能力差异无统计学意义(P>0.05);其余实验组间两两相比细胞迁移速率、侵袭能力差异均有统计学意义(均为P>0.05)。显微镜下观察发现,对照组和木犀草素12.50μmol·L^-1组C918细胞形成环状结构,且糖原PAS染色阳性,两组之间环状结构数差异无统计学意义(P>0.05);木犀草素25.00μmol·L^-1组和木犀草素50.00μmol·L^-1组仅有部分细胞形成树枝样结构,无明显环状结构形成。Western blot检测结果显示,各浓度木犀草素组p-PI3K P85、p-AKT蛋白水平均较对照组明显下调,差异均有统计学意义(均为P<0.05)。结论木犀草素可能是通过PI3K/AKT信号通路抑制C918细胞血管生成拟态形成的。

Objective To investigate the effect of luteolin on vasculogenic mimicry of human choroidal melanoma cell line C918 and its possible molecular mechanism.Methods C918 cells were cultured in vitro,luteolin 0μmol·L^-1,0.10μmol·L^-1,6.25μmol·L^-1,12.50μmol·L^-1,25.00μmol·L^-1,50.00μmol·L^-1,100.00μmol·L^-1,200.00μmol·L^-1,400.00μmol·L^-1 were applied to cells for 12 hours and 24 hours to determine the absorbance value by CCK-8 methods,and the dose-response curve was fitted by GraphPad Prism software.According to the IC50 value and the purpose of the experiment,the cells were divided into control group(0μmol·L^-1luteolin),12.50μmol·L^-1 luteolin group,25.00μmol·L^-1 luteolin group and 50.00μmol·L^-1 luteolin group.Wound scratch assay and Transwell invasion assay were used to detect cell migration and invasion ability.C918 cells were three-dimensionally cultured on Matrigel and stained with PAS.The vasculogenic mimicry of C918 cells was observed under an inverted microscope.Western blot was used to detect the expression of p-PI3K P85,AKT,and p-AKT.Results The CCK-8 assay showed that luteolin inhibited the viability of C918 cells in a concentration and time-dependent manner.GraphPad Prism software fitted the dose-effect curve,and determined that the IC50 values of luteolin on C918 cells for 12 hours and 24 hours were 163.70μmol·L^-1,and 51.46μmol·L^-1,respectively.The results of wound scratch assay and Transwell cell invasion assay showed that the cell migration rate and invasion ability of all experimental groups were significantly lower than those of the control group,and the differences were statistically significant(all P<0.0001).Compared with the 12.50μmol·L^-1 luteolin group and the 25.00μmol·L^-1 luteolin group,the difference in cell migration rate was not statistically significant(P>0.05).Compared with the 25.00μmol·L^-1 luteolin group and the 50.00μmol·L^-1 luteolin group,the difference in cell invasion capacity was not statistically significant(P>0.05).There were statistically significant differences in cell migration rate and invasion ability between the other experimental groups(all P>0.05).Inverted microscope revealed that,in the control group and 12.50μmol·L^-1 luteolin group,C918 cells formed a ring structure,and the glycogen PAS staining was positive.There was no statistically significant difference in the number of ring structures between the two groups(P>0.05).In 25.00μmol·L^-1 luteolin group and 50.00μmol·L^-1 luteolin group,only part of the cells formed a dendritic structure,and no obvious ring structure was formed.Western blot results showed that the protein levels of p-PI3K P85,p-AKT in all experimental groups were significantly lower than those in the control group,and the differences were statistically significant(all P<0.05).Conclusion Luteolin may inhibit vasculogenic mimicry of C918 cell line through PI3K/Akt signaling pathway.