Objective: To investigate the effect of curcumin on the invasion and migration of human glioma cells in vitro and explore the molecular mechanisms.
Methods: MTT assay was used for screening the optimal curcumin concentrations. The effects of curcumin on the invasion and metastasis of human glioma cell lines U251 and LN229 were tested using Transwell assay, Boyden assay and wound-healing assays. The expression of the related proteins and their interactions were determined using Western blotting and coimmunoprecipitation assay.
Results: Curcumin at the concentration of 20 μmol/L for 48 h was used as the optimal condition for subsequent cell treatment. In the two glioma cell lines, curcumin significantly suppressed the invasion and migration of the cells (P < 0.05) and lowered the expressions of hepatoma-derived growth factor (HDGF), Ncadherin, vimentin, Snail and Slug, but increased the expression of E-cadherin. Interference of HDGF in curcumin-treated glioma cells synergistically inhibited the epithelial-mesenchymal transition (EMT) signals, while overexpression of HDGF significantly reversed the inhibitory effect of curcumin on EMT; curcumin treatment could significantly reduce the binding of HDGF to β-catenin.
Conclusions: Curcumin suppresses EMT signal by reducing HDGF/β-catenin complex and thereby lowers the migration and invasion abilities of human glioma cells in vitro.
目的: 探讨姜黄素对胶质瘤细胞的侵袭、迁徙能力的影响及相关机制。
方法: 四甲基偶氮唑蓝实验筛选合适的姜黄素药物浓度; Transwell小室、Boyden小室及划痕实验检测姜黄素对胶质瘤细胞侵袭、迁移能力的影响; 蛋白免疫印迹实验和蛋白质免疫共沉淀实验检测相关蛋白质表达水平变化及相关蛋白质之间相互作用。
结果: 终浓度为20 μmol/L的姜黄素培养基培养48 h作为实验组处理因素; 姜黄素能明显降低胶质瘤细胞的侵袭、迁移能力(P < 0.05);机制分析显示, 与空白对照组相比, 姜黄素处理组HDGF、N-cadherin、Vimentin、Snail、Slug蛋白表达水平下降, E-cadherin蛋白表达水平升高; 在姜黄素处理过的胶质瘤细胞中干扰和过表达HDGF可分别协同抑制和逆转上皮细胞-间充质转化(EMT)信号; 姜黄素可以明显降低HDGF与β-catenin的结合量。
结论: 姜黄素通过抑制HDGF/β-catenin复合物, 降低了EMT信号, 从而抑制了胶质瘤细胞侵袭、迁移能力。
Keywords: cell invasion; curcumin; glioma; hepatoma-derived growth factor; β-catenin.