低剂量内皮－单核细胞激活多肽Ⅱ对人 U87MG 胶质瘤干细胞迁移和侵袭能力的影响

摘要

Objective:To explore the effect of low -dose endothelial -monocyte activating polypeptide Ⅱ (EMAPⅡ)on migration and invasion of U87MG glioma stem cells(GSCs).Methods:After the U87MG cells were cultured and isolated,the sphere cells were identified by immunofluorescent staining.The alteration of migration and invasion ability of GSCs after EMAP Ⅱ treatment was observed by Transwell assay and Matrigel Transwell assay.Protein ex-pression of PI3K and p -PI3K was detected by Western blot after EAMP Ⅱ treatment alone or combination with insu-lin -like growth factor -1 (IGF -1).Results:The presence of neural stem cell related markers CD133 and nestin proved the characteristics of GSCs.The inhibition effect on migration and invasion of GSCs was detected after EMAPⅡ treatment for 0.5h and 1h.Though the expression of PI3K was no change,the expression of p -PI3K was signifi-cantly reduced after EMAP Ⅱ treatment for 0.5h and 1h.Besides,by combination with IGF -1,an agonist of PI3K pathway,the inhibition effect on migration and invasion of GSCs by EMAP Ⅱ treatment was attenuated.Conclusion:The ability of migration and invasion of GSCs can be significantly inhibited by low -dose EMAP Ⅱ.The reduced ex-pression of p -PI3K may be attributed to the inhibition effect on migration and invasion by EMAP Ⅱ treatment toward GSCs.%目的：研究低剂量内皮－单核细胞激活多肽Ⅱ（EMAP Ⅱ）对脑胶质瘤干细胞（GSCs）迁移和侵袭能力的影响及相关分子机制。方法：应用免疫荧光方法对分离提取的细胞球进行干细胞表面标志性分子 CD133和 nestin 的检测。EMAP Ⅱ（0．05nmol／L）处理 GSCs 后，采用 Transwell 小室实验及 Matrigel Transwell 小室实验检测 GSCs 迁移和侵袭能力的变化；应用 Western blot 方法检测 PI3K 和 p －PI3K 的表达变化；应用胰岛素样生长因子（IGF －1）检测 EMAP Ⅱ作用下 GSCs 迁移和侵袭能力的改变。结果：分离提取的细胞球表面CD133和 nestin 呈阳性表达；EMAP Ⅱ作用0．5h 和1h 时产生了对 GSCs 迁移和侵袭能力的抑制作用；与EMAP Ⅱ作用0h 组相比，PI3K 的表达无变化，p －PI3K 的表达在 EMAP Ⅱ作用0．5h 和1h 时显著下降；此外， IGF －1明显阻断了 EMAP Ⅱ对 GSCs 迁移和侵袭能力的抑制作用。结论：EMAP Ⅱ能明显抑制 GSCs 的迁移和侵袭能力，其机制可能与 p －PI3K 的表达下调有关。