Biodistribution in healthy KM mice and micro PET/CT imaging in U87MG tumor-bearing nude mice of a new 18F-labeled cyclic RGD dimer
10.3969/j.issn.1007-3969.2013.06.002
- VernacularTitle:新型18F-RGD二聚体的正常生物分布及U87MG荷瘤裸鼠小动物PET/CT显像研究
- Author:
Xiao BAO
;
Mingwei WANG
;
Junyan XU
;
Yujia ZHENG
;
Jinjin JIANG
;
Yingjian ZHANG
- Publication Type:Journal Article
- Keywords:
18F-E[c(RGDfK)2];
Integrin;
Nude mice bearing U87MG human glioma xenogrfts;
Micro PET/CT
- From:
China Oncology
2013;(6):408-412
- CountryChina
- Language:Chinese
-
Abstract:
Background and purpose:Integrinαvβ3 receptor plays an important role in promoting, sustaining and regulating the angiogenesis. It is overexpressed on neovascular endothelial cells and tumor cells. RGD peptide specifically binds to integrinαvβ3, which could evaluate growth status and invasiveness of tumor. This study aimed to investigate the biodistribution in healthy KM mice and micro PET/CT imaging in U87MG tumor-bearing mice of 18F-E[c(RGDfK)2]. Methods: 18F-E[c(RGDfK)2] was produced using an automated synthesis module via a simple one-step 18F-labeling strategy of the precursor 4-NO2-3-TFMBz-E[c(RGDfK)2]. The percentage activity of injection dose per gram of tissue (%ID/g) was calculated at 0.5, 1, 2, 4 h post injection of the probe. Micro PET/CT images of U87MG tumor-bearing nude mice with or without 18F-E[c(RGDfK)2] blocking were acquired at each time point. Results: The labeling efficiency and radiochemical purity of 18F-E[c(RGDfK)2] were 10% and 98%, respectively. 18F-E[c(RGDfK)2] was excreted via renal route, with a high blood clearance. The other organs had background-level activity accumulation. At 1 h, the%ID/g of kidney, liver, intestine, muscle and blood was (1.02±0.16)%ID/g,(0.24±0.06)%ID/g, (0.35±0.03)%ID/g, (0.13±0.03)%ID/g and (0.11±0.03)%ID/g 18F-E[c(RGDfK)2] had initial high tumor uptake [(5.2±0.56)%ID/g] and good tumor-to-background contrast (5.36) at 1 h post injection. Tumor uptake for blocking group was lower than those without blocking, and T/M reduced to 1.57. Conclusion: 18F-E[c(RGDfK)2] appears a promising PET molecular imaging probe targeting integrin αvβ3, with high tumor uptake. It could be suitable for prognosis evaluation of integrin-positive tumor, selection of vascular targeting therapy and therapy effect monitoring.
