131碘标记血管抑制素体内外生物活性的研究

背景血管抑制素(Angiostatin,AS)是重要的血管生成抑制因子,能有效地抑制血管内皮细胞的增生和迁移,抑制肿瘤血管生成.目的观察AS及131I标记的AS(131I-Angiostatin,131I-AS)和单纯131I对人脐静脉内皮细胞ECV304增殖的影响及其对小鼠Lewis肺癌移植瘤质量及体积的抑制作用.设计以人脐静脉内皮细胞ECV304和荷Lewis肺癌的C57BL/6小鼠为研究对象,随机对照、重复观察测量.单位一所军医大学的放射医学实验室和医院核医学实验室.材料荷Lewis肺癌的C57BL/6雄性小鼠28只,体质量(20±2)g,5～7周龄.方法用131I标记AS,得到4种不同浓度的131I-ASA(含131I0.74 GBq/L,AS 0.5 mg/L),B(含131I 0.74 GBq/L,AS 16mg/L),C(含131I 1.48GBq/L,AS0.5mg/L),D(含131I1.48GBq/L,AS16mg/L);采用MTT法观察131I-AS、单纯AS、及单纯131I对人脐静脉内皮细胞ECV304增殖的影响.28只荷Lewis肺癌的C57BL/6小鼠(右前肢皮下移植瘤直径约1cm)随机分成4组,分别腹腔注射131I-AS(含131I11.1MBq,AS 2.5 mg/kg),AS(2.5 mg/kg),131I(11.1 MBq)和生理盐水各0.3 mL,治疗2次,间隔7d,观察肿瘤体积和质量的变化.主要观察指标①MTT法观察细胞生长抑制率(%).②动物肿瘤体积和质量的变化.结果①单纯AS在(0.5～64)mg/L浓度下,对ECV304细胞生长抑制率为(7.3±3.5)%～(41.9±43)%(与0浓度AS比较,P=0.003);A,B,C,D 4种浓度的131I-AS对ECV304细胞的抑制率分别为(23.9±2.8)%,(58.2±3.9)%,(39.1±4.1)%和(78.4±5.4)%,与AS和131I相比,抑制率明显提高(P=0.0003).②动物实验显示,AS,131I,131I-AS和生理盐水治疗14 d后,各组小鼠Lewis肺癌移植瘤的平均体积分别为(3943±236),(5 219±351),(1 963±126),(7 353±350)mm3,与生理盐水组比较AS,131I,131I-AS对小鼠Lewis肺癌移植瘤的抑瘤率分别为46.4%,29.0%,73.3%,(P=0.0001).结论131I-AS在体外能明显抑制内皮细胞的生长,在体内能明显抑制小鼠Lewis肺癌移植瘤的生长,其抑制作用强于单纯的等浓度的AS和131I.

Biological activity of 131I labeled angiostatin in vivo and in vitro

BACKGROUND: Angiostatin(AS) can effectively inhibit proliferation and migration of vascular endothelial cells and also inhibit tumor angiogenesis.OBJECTIVE: To observe the inhibitory action of angiostatin, 131I and 131 I labeled angiostatin(131I-AS) on proliferation of human umbilical vein endothelial cell ECV304 and on mass and volume of Lewis lung carcinoma (LLC) in mice.DESIGN: A randomized controlled trial with human umbilical vein endothelial cell ECV304 and Lewis lung carcinoma tumors growing in C57BL/6 mice as subjects of research.SETTING: A radiological lab and a nuclear medicine department in a military university.MATERIALS: Totally 28 LLC carrying male C57BL/6 mice, weighing(20 ± 2) g, 5 - 7 weeks old.METHODS: 131I-AS solutions of four concentrations were made: solution A(131I 0. 74 GBq/L, AS 0. 5 mg/L); solution B(131I 0.74 GBq/L, AS 16 mg/L); solution C(131I 1.48 GBq/L, AS 0.5 mg/L); solution D(131I 1.48 GBq/L, AS 16 mg/L). The effect of 131I-AS, AS alone and 131I alone on proliferation of human umbilical vein endothelial cell ECV304 was observed with MTT method. The 28 tumor carrying mice were randomly assigned into 4 groups, in each of which was injected 0.3 mL of 131I AS(131I 11.1 MBq and AS 2.5 mg/kg), AS(2.5 mg/kg), 131I(11.1MBq) and saline respectively for twice with 7 days interval. Then the change in tumor mass and volume was observed.MAIN OUTCOME MEASURES: ① The inhibition rate on cell proliferation with MTT method; ② Change in tumor mass and volume.RESULTS: ① The inhibition rate of AS alone(0. 5 -64 mg/L) on ECV304 was (7.3 ± 3.5) % - (41.9 ± 4. 3 )% ( P = 0. 003 vs AS of 0). The inhibition rate of the 4 concentrations of 131I-AS on ECV304 was(23.9±2.8)% ,(58.2±3.9)%, (39. 1 ±4. 1)% and(78.4 ±5.4)%, which were much higher than AS alone or 131I alone( P =0. 000 3) . ② The mean volume of LLC in the four groups were (3 943 ± 236), (5 219 ± 351 ), ( 1 963 ± 126),(7 353 ±350) mm3 respectively. Compared with saline group, the tumor inhibiton rate in the other 3 groups were 46.4% , 29.0% , 73.3% respectively( P =0. 000 1 ).CONCLUSION: 131I-AS inhibits proliferation of endothelial cells in vitro and inhibits LLC growth in vivo and it outdoes AS or 131I alone.