外泌体对A549细胞增殖、凋亡及迁移功能的影响

目的 观察肺癌细胞来源的外泌体对肿瘤细胞增殖、凋亡及迁移能力的影响.方法 采用多步超速离心法从肺癌A549细胞的培养液上清中分离出肺癌细胞来源的外泌体,并通过透射电子显微镜观察外泌体形态,利用Western blot 检测其表面跨膜蛋白的表达.采用 MTT 法、ELISA法分别检测外泌体对A549细胞增殖和凋亡的影响;采用Transwell法了解外泌体对A549细胞迁移能力的影响.结果 观察所提取的外泌体大小均匀,形态规则,多为圆形及椭圆形膜性囊泡盘状结构,直径30~100 nm,其外周包被被膜,表面具有丰富的四次跨膜蛋白CD9、CD63等.MTT法提示外泌体对A549细胞具有促增殖作用,且其影响具有时间和剂量依赖特征(P<0.05),ELISA法检测用外泌体共培育后的A549细胞的凋亡情况,结果显示外泌体在一定程度上抑制肿瘤细胞凋亡(F=365.496,P=0.000).Transwell法观察显示,外泌体具有促进A549细胞迁移运动的作用(F=252.005,P=0.000).结论 肺癌细胞来源的外泌体能促进A549细胞增殖、减少其凋亡、增强其迁移运动的能力.

Effect of exosomes on the proliferation,apoptosis and migration of A549 cells

Objective To observe the effect of lung cancer cell-derived exosomes on the proliferation, apoptosis and migration of tumor cells.Methods The exosomes were gathered from the culture supernatant of A549 lung cancer cells by means of multi-step ultracentrifugation.The morphology of exosomes was observed by transmission electron microscopy.Western blot was used to assess the expression of transmembrane proteins on its surface.MTT assay and ELISA were used to detect the influence of exosomes on the proliferation and apoptosis of A549 cells.By using trans-well, the impact of exosomes on migration capability of A549 cell was observed.Results The extracted exosomes had uniform size with a diameter of about 30-100 nm, most of them were oval or spherical, coated with membrane, and rich in four-times transmembrane proteins, such as CD9 and CD63.MTT assay suggested that exosomes could promote the proliferation of A549 cells in time-and dose-dependent manners (P=0.000).ELISA assay showed that exosomes inhibited the apoptosis of the tumor cells (F=365.496, P=0.000).Trans-well experiment showed that exosomes promoted migration capacity of A549 cells (F=252.005, P=0.000).Conclusion Lung cancer cell-derived exosomes can promote proliferation and reduce apoptosis of A549 cells, and increase its migration ability.