靶向uPAR 的免疫毒素对人胶质母细胞瘤及其血管生成的影响( 英文)

目的：观察靶向尿激酶型纤溶酶原激活物受体(uPAR) 的免疫毒素DTAT 和DTATEGF 对人胶质母细胞瘤体外和祼小鼠脑内生长的影响。方法：MTT 法检测靶向毒素DTAT，DTATEGF 对体外培养的人胶质瘤U87-luc 细胞系及人脐静脉细胞系(HUVEC) 的增殖影响。建立祼小鼠脑内荧光素酶标记的人胶质母细胞瘤模型。加强对流给药(CED) 方式瘤内泵入1 μg 的DTAT，DTATEGF 或对照液，生物荧光显像(BLI) 检测肿瘤生物荧光信号强度变化，免疫组织化学检测肿瘤微血管密度(MVD)。结果：体外实验显示DTAT 和DTATEG 高效抑制uPAR 表达阳性的U87-luc 和HUVEC 细胞系增殖，DTATEGF 和DTAT 抑制U87-luc 的IC50 值分别<0.01 nmol/L 和<1 nmol/L。裸小鼠肿瘤荧光信号检测显示两治疗组的信号强度较对照组增长缓慢，差异有统计学意义(P<0.05)；DTATEGF 和DTAT 组肿瘤标本的MVD 分别为 (25.1±6.5) /mm2 和(31.6±5.2) /mm2，明显少于对照组(51.3±7.4) /mm2 (P<0.01)。结论：靶向uPAR 的 DTAT 和DTATEGF 能明显抑制胶质瘤U87-luc 肿瘤细胞增殖，抑制祼小鼠脑内胶质瘤生长及其新生血管的形成。

Efficacy of antiangiogenic targeted immunotoxin DTAT and DTATEGF against glioblastoma multiforme

Objective: To investigate the in vitro and in vivo anticancer efficacy of the immunotoxin DTAT and DTATEGF against globlastoma multiforme. Methods: The in vitro cytotoxicity of DTAT and DTATEGF was measured using MTT assay. In vivo studies were performed in which 18 nude mice were randomly divided into 3 groups and the glioma xenograft intracranial mouse model was constructed with U87-luc cell line of human glioma. Then 1 μg of DTAT, or DTATEGF, or a control protein Bickel3 was delivered intracranially by convection-enhanced delivery (CED) via an osmotic minipump. The brain tumor fluorescence signal intensity was investigated by bioluminescent imaging (BLI). Microvessel density (MVD) was measured by immunchistochemistry SABC method in each group. Results: In vitro DTAT and DTATEGF were found highly potent against U87-luc cell line, with IC50 < 0.01 nmol/L and IC50 < 1 nmol/L, respectively. In vivo BLI monitoring of the control group showed progressively increasing luminescence, while in the two treatment groups, luminescence was reduced on day 8, and increased slowly (P<0.05). The MVD of DTAT (31.6±5.2)/mm2 and DTATEGF (25.1±6.5)/mm2 groups had significant difference with that of the control group (51.3±7.4) /mm2 (P<0.01). Conclusion: Both DTAT and DTATEGF have potential in clinical application against globlastoma multiforme because of their ability to target the tumor cells and neovasculature simultaneously.