南方医科大学学报 ›› 2018, Vol. 38 ›› Issue (04): 395-.

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促红细胞生成素通过激活Akt通路促进胶质瘤的快速增殖

刘自力,唐兆华,霍钢,陈飞兰,王文涛,曾纹鑫,陈鸿,李欣,陈宸   

  • 出版日期:2018-04-20 发布日期:2018-04-20

Erythropoietin accelerates the proliferation of glioma cells via activating Akt pathway

  • Online:2018-04-20 Published:2018-04-20

摘要: 目的研究促红细胞生成素(EPO)是否通过Akt信号通路促进胶质瘤的快速增殖。方法通过免疫组化法检测EPO在人 各病理级别胶质瘤中的表达差异;采用胶质瘤U87细胞系建立裸鼠皮下移植瘤模型,分为对照组和EPO处理组,监测肿瘤生长 速度差异及瘤体中EPO与p-Akt表达变化;体外实验分为对照组、EPO处理组及EPO+Akt抑制剂组,分别使用Western blot测各 组间p-Akt及cyclinD1的表达变化、CCK-8法测生长曲线、克隆形成实验检测增殖速度差异、流式细胞术检测细胞增殖周期的变 化。结果人胶质瘤标本中,高病理级别组比低级别组EPO的表达量高(P=0.0002);裸鼠移植瘤过程中,EPO处理组比对照组瘤 体中EPO及p-Akt表达显著增高(PEPO=0.0006,PP-Akt=0.0003),瘤体生长明显增快(Pvolume<0.0001,Pweight=0.0003);体外实验:与对 照组相比,EPO处理组细胞中p-Akt及cyclinD1的表达水平均明显升高(PP-Akt=0.0020,PCyclinD1=0.0022),细胞生长速度明显增快 (P3天/5天=0.020/0.028,P克隆=0.0010),增殖指数明显升高(P=0.0028),EPO+Akt 抑制剂组细胞中p-Akt 及cyclinD1的表达水平较 EPO组明显降低(PP-Akt<0.0001,PCyclinD1<0.0001),同时细胞生长速度及增殖指数均显著下降(P3天/5天=0.003/0.001,P克隆=0.0017,P增殖指数= 0.0036)。结论本研究发现EPO可通过激活Akt信号通路上调cyclinD1的表达,加快胶质瘤增殖速度。

Abstract: Objective To determine whether erythropoietin (EPO) promotes rapid proliferation of glioma through Akt pathway. Methods We detected the expression of EPO in human glioma tissues using immunohistochemistry. A nude mouse model bearing human glioma U87 cell xenograft was established and given intraperitoneal injection of EPO or saline every other day, and the tumor growth was observed. In the in vitro experiment, U87 cells were treated with PBS (control), EPO, or EPO with Akt inhibitor, and the expression of p-Akt and cyclin D1 was detected using Western blotting; the cell proliferation rate was determined using cell counting kit-8 and clone formation assay, and the cell cycle changes were analyzed with flow cytometry. Results Compared with low-grade glioma tissues, high-grade glioma tissues exhibited a significantly increased EPO expression (P=0.0002). In the tumor-bearing mice, EPO treatment significantly increased the expression of EPO (P=0.0006) and p-Akt (P=0.0003) in the tumor and obviously increased the tumor volume (P<0.0001) and weight (P=0.0003). In U87 cells cultured in vitro, EPO treatment obviously accelerated the cell proliferation (P=0.020 on day 3 and 0.028 on day 5), promoted clone formation (P=0.0010), and increased proliferation index (P=0.0028); EPO significantly enhanced the protein expression of p-Akt (P=0.0020) and cyclin D1 (P=0.0022). The application of Akt inhibitor significantly suppressed the effect of EPO in enhancing cyclin D1 and p-Akt expression (both P<0.0001) and promoting cell proliferation. Conclusion EPO can significantly accelerate the proliferation of glioma through Akt pathway.