胶质瘤干细胞来源的外泌体对血管内皮细胞增殖和迁移的影响

Effects of glioma stem cell-derived exosomes on proliferation and migration of vascular endothelial cells

摘要:

目的 探讨胶质瘤干细胞（glioma stem cells，GSCs）来源的外泌体对人脑微血管内皮细胞（HBMECs）的增殖和迁移的影响。方法 培养和分离人胶质瘤U87细胞系来源的胶质瘤干细胞（GSCs），对培养的肿瘤球细胞及其诱导分化的细胞采用免疫组织化学染色的方法鉴定。然后提取胶质瘤干细胞分泌的外泌体（GSCs-exo），分别添加不同浓度的GSCs-exo（20μg/ml、40μg/ml、60μg/ml）处理人脑微血管内皮细胞（HBMECs）。在处理结束后，采用CCK-8法检测GSCs-exo对血管内皮细胞增殖的影响、Transwell小室检测GSCs-exo对细胞迁移能力的影响。结果 肿瘤球细胞培养状态下呈悬浮生长，免疫组织化学荧光染色法证明培养的肿瘤球细胞中特异性表达CD133和Nestin，其诱导分化的细胞染色可见GFAP和Neun表达阳性。随着GSCs-exo浓度的升高，促血管内皮细胞的增殖能力逐渐增强，迁移能力也大大提高（P<0.05）。结论 在胶质瘤微环境中，胶质瘤干细胞来源的外泌体可以促进血管内皮细胞的增殖和迁移，GSCs-exo可能是胶质瘤血管形成的关键因素。

Abstract:

Objective To investigate the effects of exosomes derived from glioma stem cells (GSCs) on the proliferation and migration of human brain microvascular endothelial cells (HBMECs). Methods Human glioma U87 cell line-derived glioma stem cells (GSCs) were cultured and isolated, and the cultured tumorspheres and their differentiated cells were identified by immunohistochemical staining. The glioma stem cell-derived exosomes were extracted. HBMECs were treated with different concentrations of GSCs-exo (20 μg/ml, 40 μg/ml, 60 μg/ml). At the end of the treatment, the effect of GSCs-exo on the proliferation of vascular endothelial cells was examined by CCK-8 method, and the effect of GSCs-exo on cell migration ability was detected by Transwell chamber. Results The tumorspheres were suspended in the culture state. Immunohistochemical staining showed that Nestin and CD133 were specifically expressed in the cultured tumorspheres. The staining of the cells induced by the tumorspheres showed positive expression of GFAP and Neun. With the increase of GSCs-exo concentration, the proliferative capacity of vascular endothelial cells increased gradually, and the migration ability was also greatly improved (P<0.05). Conclusions In the glioma microenvironment, glioma stem cell-derived exosomes can promote proliferation and migration of vascular endothelial cells, GSCs-exo may be a key factor in angiogenesis of glioma.