CAJ | 학술논문

目的评价引入2个聚乙二醇(PEG4)对精氨酸-甘氨酸-天冬氨酸(RGD)环肽二聚体(Dimer:E[c(RGDfK)]2)体外受体结合亲和力和体内药代动力学特征的影响,以及99Tcm标记2PEG4-Dimer用于整合素αvβ3阳性肿瘤显像的前景.方法用免疫组织化学实验测定U87MG人神经胶质瘤细胞以及肿瘤组织中整合素αvβ3的表达.通过U87MG细胞受体竞争结合实验测定RGD环肽单体c(RGDyK)、联肼尼克酰胺(HYNIC)-Dimer和HYNIC-2PEG4-Dimer对125I-c(RGDyK)的半数抑制浓度(IC50).采用无亚锡一步法制备99Tcm-HYNIC-Dimer和99Tcm-HYNIC-2PEG4-Dimer,评价"TcmHYNIC-2PEG4-Dimer在荷U87MG瘤裸鼠的生物分布并进行γ显像.采用非配对t检验法对实验数据进行分析.结果 U87MG细胞和荷瘤裸鼠肿瘤组织中高表达整合素αvβ3.HYNIC-2PEG4-Dimer比c(RGDyK)和HYNIC-Dimer有更高的整合素αvβ3亲和力(IC50分别是0.8,27和2.4 nmol/L).99Tcm-HYNIC-Dimer和99Tcm-HYNIC-2PEG4-Dimer的99Tcm标记率均＞95%,经Sep-Pek C18柱纯化后其放化纯＞99%.生物分布实验显示,2种标记物均主要经肾排泄,在注射后2h,肿瘤对99Tcm-HYNIC-2PEG4-Dimer的摄取为99Tcm-HYNIC-Dimer的2.7倍[(5.71±0.96)%ID/g和(2.10±0.50)%ID/g],t=4.80,P＜0.05,与体外受体竞争结合实验数据相一致.γ显像结果显示,注射99Tcm-HYNIC-2PEG4-Dimer后0.5 h肿瘤即清晰可见,随时间延长,体内放射性本底明显减低,显像对比度增高.结论 99Tcm-HYNIC-2PEG4-Dimer有希望用于整合素αvβ3阳性肿瘤显像.
목적 평개인입2개취을이순(PEG4)대정안산-감안산-천동안산(RGD)배태이취체(Dimer:E[c(RGDfK)]2)체외수체결합친화력화체내약대동역학특정적영향,이급99Tcm표기2PEG4-Dimer용우정합소αvβ3양성종류현상적전경.방법 용면역조직화학실험측정U87MG인신경효질류세포이급종류조직중정합소αvβ3적표체.통과U87MG세포수체경쟁결합실험측정RGD배태단체c(RGDyK)、련정니극선알(HYNIC)-Dimer화HYNIC-2PEG4-Dimer대125I-c(RGDyK)적반수억제농도(IC50).채용무아석일보법제비99Tcm-HYNIC-Dimer화99Tcm-HYNIC-2PEG4-Dimer,평개"TcmHYNIC-2PEG4-Dimer재하U87MG류라서적생물분포병진행γ현상.채용비배대t검험법대실험수거진행분석.결과 U87MG세포화하류라서종류조직중고표체정합소αvβ3.HYNIC-2PEG4-Dimer비c(RGDyK)화HYNIC-Dimer유경고적정합소αvβ3친화력(IC50분별시0.8,27화2.4 nmol/L).99Tcm-HYNIC-Dimer화99Tcm-HYNIC-2PEG4-Dimer적99Tcm표기솔균＞95%,경Sep-Pek C18주순화후기방화순＞99%.생물분포실험현시,2충표기물균주요경신배설,재주사후2h,종류대99Tcm-HYNIC-2PEG4-Dimer적섭취위99Tcm-HYNIC-Dimer적2.7배[(5.71±0.96)%ID/g화(2.10±0.50)%ID/g],t=4.80,P＜0.05,여체외수체경쟁결합실험수거상일치.γ현상결과현시,주사99Tcm-HYNIC-2PEG4-Dimer후0.5 h종류즉청석가견,수시간연장,체내방사성본저명현감저,현상대비도증고.결론 99Tcm-HYNIC-2PEG4-Dimer유희망용우정합소αvβ3양성종류현상.
Objective (1) To evaluate the effect of insertion of two 15-amino-4,7,10,13-tetraoxapentadecanoic (2 PEG4 ) linkers into cyclic Arg-Gly-Asp (RGD) Dimer E [c(RGDfK)]2 on receptor binding in vitro, (2) to assess its biodistribution in vivo and (3) to investigate the value of 99Tcm labeled 2PEG4-Dimer for integrin αvβ3-positive tumors imaging.Methods The expression of U87 human glioma cells and integrin αv β3 was determined by immunofluorescence staining.The half-inhibition concentrations (IC50) for 125 I-cyclo (Arg-Gly-Asp-D-Tyr-Lys) (c(RGDyK) ) of c ( RGDyK ), hydrazinonictinamide ( HYNIC )-Dimer and HYNIC-2PEG4-Dimer binding to integrin αvβ3 were measured.99Tcm-HYNIC-Dimer and 99Tcm-HYNIC-2PEG4-Dimer were synthesized using non-SnCl2 formulation.Biodistribution and imaging studies were performed in nude mice bearing human glioma xenografts.The unpaired t test was used for statistical analysis.Results The labeling yield of the two radiotracers was more than 95%, and the radiochemical purity was more than 99% through Sep-Pek C18 cartridge.HYNIC-2PEG4-Dimer had significantly higher binding affinity of integrin αvβ3 than c(RGDyK) and HYNIC-Dimer (IC50 = 0.8 nmol/L, 27 nmol/L and 2.4 nmol/L, respectively).Biodistribution study showed that 99Tcm-HYNIC-2PEG4-Dimer was mainly excreted via the kidney.The tumor uptake of 99Tcm-HYNIC-2PEG4-Dimer was higher than that of 99Tcm-HYNIC-Dimer at 2h post injection ((5.71 ±0.96) and (2.10 ±0.50) % ID/g, t =4.80, P＜0.05).The xenografted tumors were visible at 0.5 h post injection and the image contrast increased with time due to the tracer clearance of the background tissue.Conclusion 99 Tcm-HYNIC-2PEG4-Dimer is a promising radiotracer for integrin αvβ3-positive tumor imaging.