The preparation and biological evaluation of 99mTc-MAG3-glucose

目的 制备99mTc-MAG3-葡萄糖(99m Tc-MAG3 -Glu)并研究其肿瘤定位性能,以探讨其应用于肿瘤显像的可能性.方法 β3-N-巯基乙酰基-甘氨酰-甘氨酰-甘氨酰-葡萄糖(MAG3 -Glu)经化学合成并用99mTc标记,对标记物在荷肉瘤S180的小鼠体内的生物分布与显像进行研究,并与18F-FDG的生物分布进行对比.结果 99mTc对MAG3-Glu的标记率大于90％.注射后lh、3h和5 h99mTc-MAG3-Glu在肿瘤中的摄取率分别为(2.45±0.25)、(2.23±0.53)和(2.00±0.89) ％ID/g,注射后5h肿瘤与除肝、肾、肺外的正常组织的T/NT值均高于1.7,其中肿瘤/血液、肿瘤/肌肉和肿瘤/脑分别为1.71、5.71与28.57.静脉注射3h后,肿瘤即可显影,随时间延长,肿瘤与正常组织对比度略有增高.与18F-FDG相比,99mTc-MAG3-Glu在肿瘤中的摄取率以及肿瘤与大多数组织的T/NT值较低,但肿瘤与肌肉、心脏、脾和脑的T/NT值高于18F-FDG,尤其是肿瘤与脑的T/NT值显著高于18F-FDG.结论 99mTc-MAG3-Glu在肿瘤中具有较高的摄取率和较长的滞留时间,有可能应用于肿瘤显像,其肿瘤与脑的摄取比值很高,在脑瘤以及大脑附近的肿瘤显像中较18F-FDG更具优势.Objective To investigate the possibility of 99mTc-MAG3-Glucosc used for tumor imaging,99mTc-MAG3-Glucose was synthesized and its tumor localizing properties were studied.Methods β-N-mercaptoaeetyl-Gly-Gly-Gly-glucose ( MAG3-Glu)was labeled with 99mTc.The labelled compound was injected into the mice bearing S180 tumor,and biodistribution study and imaging were performed.The biodistribution of 18F-2-fluoro-desoxy glucose( 18F-FDG) at 5 h postinjection was also studied for comparison.Results 99mTc labeling yield was greater than 90％.The tumor uptakes at 1 h,3 h and 5 h postinjection were ( 2.45 ± 0.25 ) ％ ID/g,( 2.23 ± 0.53 ) ％ ID/g and ( 2.00 ±0.89)％ID/g,respectively.The T/NTs were greater than 1.7 for tumor over all other normal tissues excepted for lung,kidney and liver at 5 h postinjection.Tumor/blood,tumor/muscle and tumor/brain were 1.71,5.71 and 28.57,respectively.Tumor was visualized at 3 h postinjection,and the contrast became slightly sharper with time lasted.Compared with 18F-FDG,99Tc-MAG3-glu had lower tumor uptake and T/NTs for most tissues.But its T/NTs for tumor over muscle,heart,spleen and brain,especially for tumor over brain,were higher.Conclusions The results suggested the potential utility of 99mTc-MAG3-Glu as a suitable tumor imaging agent.The high tumor over brain uptake ratio indicated that 99Tc-MAG3-glu may have advantages in imaging brain tumor and the tumor near brain.中国科技核心期刊(ISTIC)013133-1350