目的： 研究TGF-β2对胶质瘤干细胞侵袭能力的影响及其可能机制。 方法： 收集2016年4月至2017年4月中国医科 大学附属第一医院神经外科手术切除的8例人多形性成胶质细胞瘤组织标本，通过胰蛋白酶消化法进行胶质瘤细胞原代培养，部 分胶质瘤细胞加入含有EGF、bFGF、B27的DEME/F12培养基中进行无血清培养获得悬浮生长的肿瘤细胞球，免疫荧光染色及分 化实验验证肿瘤球是否为胶质瘤干细胞。ELISA方法检测胶质瘤干细胞分泌TGF-β2的水平，转染TGF-β2 siRNA后应用Tran- swell方法检测TGF-β2对胶质瘤侵袭能力影响，Western blotting检测TGF-β2对胶质瘤干细胞中基质金属蛋白酶（matrix metallo- proteinase，MMP）表达影响。 结果： 通过免疫荧光染色及分化实验证明原代培养的悬浮生长肿瘤细胞球为胶质瘤干细胞，肿瘤 细胞球表达CD133，在含血清培养基中可以分化为神经元和胶质细胞。胶质瘤干细胞比原代培养的胶质瘤 TGF-β2 分泌水平 明显升高[(74.13±3.63) vs (46.13±2.61) pg/ml, P<0.05]。沉默 TGF-β2 可以降低胶质瘤干细胞侵袭细胞数[(105.71±8.69) vs (63.67±5.93)个，P<0.05]，并抑制MMP-2和MMP-9表达（均P<0.05）。 结论： TGF-β2 通过 MMP-2 和 MMP-9 通路增强胶质瘤 干细胞的侵袭能力。

Objective: To study the effect and possible mechanism of TGF-β2 on the invasion of glioma stem cells (GSCs). Methods: Tumor tissues of 8 patients with glioblastoma multiforme, who underwent resection at Department of Neurosurgery of the First Affiliat- ed Hospital of China Medical University during April 2016 to April 2017, were collected. The primary culture of glioma cells were con- ducted with trypsin digestion. Partial primary glioma cells were seeded into serum-free DMEM/F12 culture medium containing EGF, bFGF and B27 to obtain suspension of tumor spheres. Immunoflurenscent staining and differentiation assay were used to detect whether the tumor spheres were GSCs. TGF-β2 secretion ability of GSCs was determined by ELISA assay. After transfection of TGF-β2 siRNA, the invasion ability of glioma stem cells was determined by Transwell assay. Western blotting was used to examine the effect of TGF-β2 on expression of matrix metalloproteinases (MMP) in glioma stem cells. Results: The suspended tumor spheres were proved to be GSCs by immunofluorescent staining and differentiation assay; the tumor spheres expressed the marker of GSCs（CD133）and had the ability to multi-differentiate (glia and neuronal cells). Compared with the primary glioma cells, Glioma stem cells exerted significantly improved TGF-β2 secretion ability ([74.13±3.63] vs [46.13±2.61] pg/ml, P<0.05); and TGF-β2 silencing significantly reduced the inva- sion ability of glioma stem cells ([105.71±8.69] vs [63.67±5.93], P<0.05) and inhibited MMP-2 and MMP-9 expressions. Conclusion: TGF-β2 can promote the invasiveness of glioma stem cells through MMP-2 and MMP-9 pathway.

辽宁省博士启动基金资助项目（No. 201501004）