Dataset Information

Development of a Novel PET Tracer [18F]AlF-NOTA-C6 Targeting MMP2 for Tumor Imaging.

ABSTRACT:

Background and objective

The overexpression of gelatinases, that is, matrix metalloproteinase MMP2 and MMP9, has been associated with tumor progression, invasion, and metastasis. To image MMP2 in tumors, we developed a novel ligand termed [18F]AlF-NOTA-C6, with consideration that: c(KAHWGFTLD)NH2 (herein, C6) is a selective gelatinase inhibitor; Cy5.5-C6 has been visualized in many in vivo tumor models; positron emission tomography (PET) has a higher detection sensitivity and a wider field of view than optical imaging; fluorine-18 (18F) is the optimal PET radioisotope, and the creation of a [18F]AlF-peptide complex is a simple procedure.

Methods

C6 was conjugated to the bifunctional chelator NOTA (1, 4, 7-triazacyclononanetriacetic acid) for radiolabeling [18F]AlF conjugation. The MMP2-binding characteristics and tumor-targeting efficacy of [18F]AlF-NOTA-C6 were tested in vitro and in vivo.

Results

The non-decay corrected yield of [18F]AlF-NOTA-C6 was 46.2-64.2%, and the radiochemical purity exceeded 95%. [18F]AlF-NOTA-C6 was favorably retained in SKOV3 and PC3 cells, determined by cell uptake. Using NOTA-C6 as a competitive ligand, the uptake of [18F]AlF-NOTA-C6 in SKOV3 cells decreased in a dose-dependent manner. In biodistribution and PET imaging studies, higher radioactivity concentrations were observed in tumors. Pre-injection of C6 caused a marked reduction in tumor tissue uptake. Immunohistochemistry showed MMP2 in tumor tissues.

Conclusions

[18F]AlF-NOTA-C6 was easy to synthesize and has substantial potential as an imaging agent that targets MMP2 in tumors.

SUBMITTER: Liu Q

PROVIDER: S-EPMC4634933 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Publications

Development of a Novel PET Tracer [18F]AlF-NOTA-C6 Targeting MMP2 for Tumor Imaging.

Liu Qinghua Q Pan Donghui D Cheng Chao C Zhang Dazhi D Zhang Anyu A Wang Lizhen L Jiang Hongdie H Wang Tao T Liu Hongrui H Xu Yuping Y Yang Runlin R Chen Fei F Yang Min M Zuo Changjing C

PloS one 20151105 11

<h4>Background and objective</h4>The overexpression of gelatinases, that is, matrix metalloproteinase MMP2 and MMP9, has been associated with tumor progression, invasion, and metastasis. To image MMP2 in tumors, we developed a novel ligand termed [18F]AlF-NOTA-C6, with consideration that: c(KAHWGFTLD)NH2 (herein, C6) is a selective gelatinase inhibitor; Cy5.5-C6 has been visualized in many in vivo tumor models; positron emission tomography (PET) has a higher detection sensitivity and a wider fie ...[more]

PMID: 26540114

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Dataset Information

Development of a Novel PET Tracer [18F]AlF-NOTA-C6 Targeting MMP2 for Tumor Imaging.

Background and objective

Methods

Results

Conclusions

Publications

Development of a Novel PET Tracer [18F]AlF-NOTA-C6 Targeting MMP2 for Tumor Imaging.

Similar Datasets

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