人多发性骨髓瘤细胞株RPM18226细胞对共培养内皮细胞的作用

Role of multiple myeloma cells on normal endothelial cells in co-culture system

【摘要】目的在体外共培养体系中研究人多发性骨髓瘤（MM）细胞对人正常内皮细胞的作用。方法建立人MM细胞株RPM18226细胞与正常人脐静脉内皮细胞（HUVEC）的体外共培养体系；以同期单独培养的HUVEC为对照，用电子显微镜和光学显微镜对与RPM18226细胞共培养的HUVEC进行细胞超微结构和细胞形态学观察；用刮痕迁移实验、管状结构形成实验评价体外内皮细胞血管新生的能力；并以Western blot和流式细胞术分别检测脑源性神经营养凶子（BDNF）、Endoglin与TrkB、Tie2、B3整合素、血管细胞黏附分子－1蛋白的表达。结果与同期单独培养的正常内皮细胞对照相比，共培养后的部分内皮细胞胞体伸展并首尾排列成一行；超微结构m现胞核增大、核r增大、核质比例增大，内质网疏松、变形，细胞表面纤毛减少；共培养体系中细胞管状结构形成数量和迁移细胞数较单独培养体系分别增加了112％和136％；BDNF、Endoglin、TrkB、Tie2、B，整合素和血管细胞黏附分子－1蛋白的表达亦明显上调。结论MM细胞与人正常内皮细胞共培养后，内皮细胞有明显的趋瘤特征和较强的血管新生能力，推测MM患者骨髓中骨髓瘤细胞通过对相邻内皮细胞的作用促进血管新生，且新生血管的内皮细胞性质与行为不同于正常内皮细胞。

Objective To study the influence of myhiple myeloma （ MM ） cells on normal endothelial cells in co-culture system in vitro. Methods A co-culture system of human MM cell line RPMI8226 with human umbilical vein endothelial cells （ HUVECs ） was established in vitro. Monocuhured normal endothelial cells were used as control. Light microscopy and transmission electron microscopy were used to observe the morphology of the endothelial cells. The effects of HUVECs co-cultured with RPMI8226 on HUVECs anglogenesis were studied by modified transwell migration assay and net-like formation assay. The protein expression of brain derived neurotrophic factor （ BDNF ）, TrkB, Endoglin ,Tic-2, [33 integrin and vascullar cell adhension molecule-1 （VCAM-1） in HUVECs were determined by FACS and Western blot analysis, respectively. Results The morphology of HUVECs co-cultured with RPM18226 cells became a narrower apart of extended shape as they began to align themselves. The sizes of nucleus and nueleolus were enlarged with an increased ratio of nuclear to nucleoplasm. The endoplasm was loosed and distorted and the number of surface microvilli decreased. The RPMI8226 cell stimulated the migration and net-like formation of HUVEC, the number of net-like structure and migration cell being increased by 112% and 136% , respectively, compared with that of monocuhured HUVECs. The expressions of BDNF,TrkB, Endoglin,Tie-2 ,[33 integrin and VCAM- 1 in the ECs co-cultured with RPMI8226 were all up-regulated in comparison with those in the controls. Conclusion The MM cells promote formation of new vessels in co-cuhured endothelial cells and the endothelial cells in MM are different from the normal ECs in character, and behavior.