摘要目的:探讨肿瘤细胞来源的外泌体对神经母细胞瘤细胞增殖和转移的影响。方法:使用外泌体提取纯化试剂盒对人神经母细胞瘤SH-SY5Y细胞培养上清液中的外泌体进行提取和纯化，通过透射电子显微镜、蛋白免疫印记法对外泌体的形态、大小和标志蛋白进行鉴定。根据细胞培养基中是否加入外泌体，分为外泌体组和对照组，利用CCK-8法和Transwell实验检测外泌体对SH-SY5Y增殖活力和转移能力的影响。结果:在透射电子显微镜下可见外泌体为茶托样形状，并被一层磷脂膜所包被，直径在30～150 nm之间；蛋白免疫印记法显示，位于外泌体内、外的标志蛋白TSG101和CD63均有富集。细胞增殖实验结果表明在共培养48 h后外泌体组的细胞存活率为(0.95±0.02)与对照组(0.88±0.05)比较，差异无统计学意义( t＝2.317， P＝0.081 4)；但是在共培养72 h后外泌体组的细胞存活率为(1.09±0.09)较对照组(0.92±0.03)明显提高，且组间差异有统计学意义( t＝3.027， P＝0.038 9)。细胞转移实验结果显示，外泌体组SH-SY5Y细胞的迁移数量为(28.8±5.02)个较对照组(14.8±4.76)个明显增加，且组间差异有统计学意义( t＝4.523， P＝0.001 9)。 结论:神经母细胞瘤细胞来源的外泌体能促进肿瘤细胞的增殖和转移，表明肿瘤来源的外泌体能成为交叉信号传递的平台，在促进肿瘤细胞生长方面发挥自分泌的作用。

abstractsObjective:To explore the effect of exosomes on the proliferation and migration of neuroblastoma cell.Methods:Exosomes were extracted and purified from cell supernatant of SH-SY5Y using extraction and purification kit. The morphology, size and protein marker of exosomes were identified by transmission electron microscopy and Western blot. According to whether or not exosomes were added into cell culture medium, they were divided into exosome and control groups. The effect of exosomes on the proliferation and migration of SH-SY5Y was detected by CCK-8 and Transwell assay.Results:Under transmission electron microscope, exosomes assumed the shape of saucers and were covered by a phospholipid membrane with a diameter of 30~150 nm. Western blot indicated that TSG101 and CD63 were enriched in exosomes. Cell proliferation test revealed that cell survival rate of exosome group after 48h co-culturing was not significantly different from that of control group (0.95±0.02 vs. 0.88±0.05, t=2.317, P=0.0814). However, cell survival rate of exosome group after 72h co-culturing was significantly higher than that of control group (1.09±0.09 vs. 0.92±0.03, t=3.027, P=0.0389). Cell transfer experiment indicated that the number of SH-SY5Y cells increased markedly in exosome group than that in control group (28.8±5.02 vs. 14.8±4.76, t=4.523, P=0.0019). Conclusions:Tumor-derived exosomes may promote proliferation and metastasis of neuroblastoma cell in vitro. The present study has confirmed a novel mechanism by which exosomes from tumour cell offer an efficient platform for transducing cross-talk signals and play autocrine roles in promoting tumor cell growth.