人脐带间充质干细胞来源外泌体抑制髓母细胞瘤Daoy细胞增殖并促其凋亡

Exosomes from human umbilical cord-derived mesenchymal stem cells suppress the proliferation and promote the apoptosis of medulloblastoma Daoy cells

背景:间充质干细胞能够产生大量的与其生物学功能相似的外泌体,但间充质干细胞来源外泌体对髓母细胞瘤Daoy细胞的影响仍不清楚。目的:探讨人脐带间充质干细胞来源外泌体对髓母细胞瘤Daoy细胞增殖、凋亡的影响以及可能机制。方法:分离、培养人脐带间充质干细胞,提取第4代人脐带间充质干细胞来源外泌体,Western blot检测外泌体标志蛋白CD9和CD81的表达。将人脐带间充质干细胞来源外泌体与Daoy细胞共培养96 h,采用流式细胞术、克隆形成实验检测Daoy细胞的增殖情况;流式细胞术检测Daoy细胞的凋亡情况;Western blot检测凋亡相关蛋白的表达水平。结果与结论:Western blot检测人脐带间充质干细胞来源外泌体CD9和CD81呈阳性表达。与对照组比较,人脐带间充质干细胞来源外泌体抑制Daoy细胞增殖和克隆形成(P<0.05,P<0.01);促进Daoy细胞凋亡(P<0.01);凋亡相关蛋白Cyclin D1和Bcl-2表达下调(P<0.05),Caspase-3表达上调(P<0.01)。结果表明,人脐带间充质干细胞来源外泌体可能通过调节细胞周期以及凋亡相关蛋白表达来抑制髓母细胞瘤Daoy细胞的增殖,并促进其凋亡。

BACKGROUND:Mesenchymal stem cells can produce a large number of exosomes,which has similar biological activity to mesenchymal stem cells.However,the effect of mesenchymal stem cell-derived exosomes on Daoy cells of medulloblastoma has yet to be determined.OBJECTIVE:To investigate the effect of exosomes derived from human umbilical cord-derived mesenchymal stem cells on the proliferation and apoptosis of medulloblastoma Daoy cells and its potential mechanism.METHODS:Human umbilical cord-derived mesenchymal stem cells were isolated and cultured.Passage 4 of human umbilical cord-derived mesenchymal stem cells was collected.The expression of exosome markers CD9 and CD81 was detected by western blot assay.Exosomes extracted from human umbilical cord-derived mesenchymal stem cells were cocultured with Daoy cells for 96 hours.The proliferation of Daoy cells was detected by flow cytometry and colony formation assay.The apoptosis of Daoy cells was detected by flow cytometry.The expression levels of apoptosis related proteins were detected by western blot assay.RESULTS AND CONCLUSION:Western blot assay results showed that exosomes from human umbilical cord-derived mesenchymal stem cells were positive for CD9 and CD81.Compared with the control group,exosomes from human umbilical cord-derived mesenchymal stem cells inhibited the proliferation of Daoy cells and the formation of colonies(P<0.05,P<0.01),and promoted Daoy cell apoptosis(P<0.01).Apoptosis related proteins Cyclin D1 and Bcl-2 were down regulated(P<0.05),but expression level of Caspase-3 was up-regulated(P<0.01).The results confirm that human umbilical cord-derived mesenchymal stem cells derived exosomes can suppress the proliferation of Daoy cells and promote its apoptosis possibly by regulating cell cycle and apoptosis related protein expression.