转染HSV-TK的内皮祖细胞的靶向血管新生治疗胶质瘤体内外实验

Antiglioma activity of endothelial progenitor cells transduced with HSV-TK via inhibiting angiogenesis in vitro andinvivo

目的 探讨转染单纯疱疹病毒胸苷激酶（herpes simplex virus thymidine kinase，HSV—TK）的内皮祖细胞（endothelial progenitor cells，EPCs）靶向血管新生及对胶质瘤的治疗作用。方法 将转染HSV-TK的EPCs和脐静脉内皮细胞、U87与U251胶质瘤细胞，以不同比例混合，经更昔洛韦（ganciclovir，GCV）作用，观察其旁观者效应。将转染HSV—TK的EPCs经尾静脉注入裸鼠皮下胶质瘤模型，观察各组肿瘤体积的变化，免疫组化检测各组中血管情况。结果 转染HSV—TK的EPCs对内皮细胞与胶质瘤细胞的旁观者效应，呈现时间依赖性与细胞比例依赖性。静脉注射转染后的EPCs，对裸鼠皮下胶质瘤生长具有明显抑制作用，并抑制血管生成。结论 转染HSV-TK的EPCs可能通过靶向血管新生来抑制胶质瘤生长。

Objective To investigate the potentiality of herpes simplex virus thymidine kinase transduced endothelial progenitor cells （EPC-TK） as angiogenesis-targeting vector in the glioma treatment in vitro and in vivo. Methods EPC-TK were mixed with human umbilical vein endothelial cells （HUVECs）, U87 or U251 cells at various ratios for ganciclovir （GCV） treatment. The bystander effect was observed by counting the survival cells using MTT assay, and the apoptotic cells were determined by annexin-V and propidium iodide （PI） staining. EPC-TK, EPCs, or phosphate buffered saline （PBS） were injected into the nude mice model of glioma xenograft by tail vein, for the EPC-TK group, EPC group, and PBS group, respectively. And then the changes of tumor volume and tumor vaseulature were observed. Results GCV killed most EPC-TK and reduced the number of other viable cells in a cell： cell ratio-dependent and time- dependent manner. EPC-TK obviously inhibited tumor growth. The tumor volumes on day 21 were 1741. 204-576.10 mm^3, 3275. 52±710.86 mma and 3033.09±1134.86 mma in the EPC-TK, EPC and PBS group, respectively. EPC-TK also displayed a significant effect on the inhibition of tumor angiogenesis. Conclusion EPC TK can exert a potent antiglioma effect via inhibiting angiogenesis.