Study of microSPECT-CT imaging of mice orthotopic glioma with 99Tcm-Galacto-RGD2
10.3760/cma.j.issn.0254-5098.2015.12.001
- VernacularTitle:原位脑胶质瘤99Tcm-Galacto-RGD2microSPECT/CT靶向显像研究
- Author:
Can CUI
;
Feng WANG
;
Guoqiang SHAO
;
Liangsheng LUO
;
Zizheng WANG
- Publication Type:Journal Article
- Keywords:
Glioma;
Target region;
Molecular imaging;
Integrin αvβ3;
Arg-Gly-Asp peptide
- From:
Chinese Journal of Radiological Medicine and Protection
2015;35(12):881-885,952
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the synthesis, in vivo biodistribution of 99Tcm-HYNIC-PEG4-E[PEG4-c (RGDfk)] 2 (99 Tcm-Galacto-RGD2), and its potential usage for targeted imaging of mice orthotopic glioma.Methods 99Tcm-Galacto-RGD2 was synthesized straightforward and its radiochemical purity and stability and distribution in mice were analyzed.MicroSPECT-CT imaging was done in a mice orthotopic glioma model, which had been set up with U87MG cells, after administration of 99Tcm-Galacto-RGD2.Region of interest (ROI) of glioma was drawn on SPECT-CT section images to quantify tumor uptake (％ ID/cm3).Glioma was harvested for pathological examination.Linear-regression was used to analyze the relationship between integrin αvβ3 and tumor uptake (％ID/cm3).Results The radiochemical purity of 99Tcm-Galacto-RGD2 was (97.7 ±0.8)％ and stable in vitro.Hynic-Galacto-RGD2 could specifically bind to integrin αv β3 of tumor cells with a IC50 of (18 ± 3) nmol/L.After tail vein injection, 99Tcm-Galacto-RGD2 was rapidly discharged from the blood, liver, kidneys and had a relative low concentration in normal brain tissue.MicroSPECT-CT imaging demonstrated that, after 60 min of injection, this drug was well uptaken by glioma tumor than that after 30 min (t =7.13 ,P ＜0.05), and the tumor to normal brain tissue (T/B) uptake ratio of 99Tcm-Galacto-RGD2 was 13.92± 3.43.Injection of HYNICGalacto-RGD2 2 min prior to 99Tcm-Galacto-RGD2 injection extensively reduced the uptake of radioactive drug in tumor tissue (t =11.36, P ＜ 0.05).Bland-Altman analysis showed that tumor volume based on SPECT-CT imaging measurement had almost same value with the tumor reference volume (95％ CI =-11.94％-11.92％).In addition, the tumor uptake of 99Tcm-Galacto-RGD2 and cellular integrin αvβ3 expression level had a linear relationship (R2 =0.896).Conclusions Stable 99Tcm-Galacto-RGD2 can be synthesized easily and is applicable for microSPECT-CT imaging analysis of orthotopic glioma in mice together with the evaluation of integrin αvβ3 level in tumor.
