缺氧与胶质瘤细胞血管生成拟态现象的体外研究

Hypoxia and Vasculogenic Mimicry Assay of Glioma Cells in Vitro

目的研究缺氧对胶质瘤细胞血管生成拟态的影响及其可能机制。方法建立Ⅰ型鼠尾胶原蛋白三维培养体系，观察恶性U251人胶质瘤细胞在常氧（常氧组）和缺氧（缺氧组）条件下形成血管生成拟态（VM）的差异；应用实时荧光定量RT-PCR及Westernblot技术检测两组缺氧诱导因子-1α（HIF-1α）和血管内皮生长因子-A（VEGF-A）的表达。结果三维培养48h，缺氧组能形成大量管形VM，而常氧组不形成或形成较少管形VM（P〈0．05）；缺氧组VEGF-A，HIF-1αmRNA和蛋白表达水平明显较常氧组高（P〈0．05）。结论在U251人胶质瘤细胞体外三维培养中存在血管生成拟态现象；缺氧能促进胶质瘤VM的形成，诱导HIF-1α和VEGF-A表达可能是其作用机制之一。

Objective To investigate the effect of hypoxia on vasculogenic mimicry（VM） formation in glioma cells in vitro and to explore possible mechanisms involved. Methods A three-dimensional cell culture system for human glioma cell line U251 was established and VM formation nnder normoxic and hypoxic conditions were observed. Real Time reverse-transcription-polymerase chain reaction （ Real Time RT-PCR） and Western blot were used to detect the effect of hypoxia on the mRNA and protein expression of hypoxic inducible factor- 1α（HIF-1α） ,vascular endothelial growth factor-A（VEGF-A） respectively. Results After cells were cuhured for 48h,tubular VM was pro- duced clearly under hypoxic conditions,while cells cultured under normoxic conditions failed to form VM or formed nnelearly tubular VM（P 〈 0.05 ）. The mR NA and protein expression levels of VEGF-A and HIF-1αwere significantly higher under hypoxia than under normoxia（ P 〈 0.05 ）. Conclusion Hypoxia can induce VM formation in human glioma cell line U251 in three-dimensional cell culture system by regulating the expression of HIF-1α and VEGF-A.