A dual-labeled cRGD-based PET/optical tracer for pre-operative staging and intraoperative treatment of colorectal cancer

American Journal of Nuclear Medicine and Molecular Imaging

Claudia Sewing¹  Albert D Windhorst²  Danielle J Vugts³  graaf⁴  Henricus JM H⁵  Babs G Sibinga Mulder⁶ 

[1] Biomedical Photonic Imaging Group, University of Twente, Enschede, The Netherlands;Curadel, LLC, Marlborough, MA, U.S.A.;Department of Nuclear Medicine, Leiden University Medical Center, Leiden, The Netherlands;Department of Nuclear Medicine, VU Medical Center, Amsterdam, The Netherlands;Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands;Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands

关键词: Hybrid tracer;    colorectal cancer;    molecular imaging;    PET imaging;    near-infrared fluorescence imaging;    cRGD;   

DOI  :  

学科分类：过敏症与临床免疫学

来源: e-Century Publishing Corporation

【 摘 要 】

cRGD peptides target integrins associated with angiogenesis (e.g., αvβ3) and cancer, and have been used as binding ligands for both positron emission tomography (PET) and near-infrared fluorescence (NIRF) optical imaging. This study introduces the hybrid tracer cRGD-ZW800-1-Forte-[89Zr]Zr-DFO, which is based on a novel zwitterionic fluorophore structure that reduces non-specific background uptake during molecular imaging of tumors. An in vitro binding assay was used to validate tracer performance. 10 nmol ZW800F-cRGD-Zr-DFO was injected in mice (n=7) bearing orthotopic human colorectal tumors (HT29-luc2) for tumor detection with NIRF imaging. Subsequently, ZW800F-cRGD-Zr-DFO was loaded with 89Zr and 10 nmol cRGD-ZW800-1-Forte-[89Zr]Zr-DFO (3 MBq) was injected in mice (n=8) for PET/CT imaging. Imaging and biodistribution was performed at 4 and 24 h. NIRF imaging was performed up to 168 h after administration. Sufficient fluorescent signals were measured in the tumors of mice injected with ZW800F-cRGD-Zr-DFO (emission peak ~800 nm) compared to the background. The signal remained stable for up to 7 days. The fluorescence signal of cRGD-ZW800-1-Forte-[89Zr]Zr-DFO remained intact after labeling with 89Zr. PET/CT permitted clear visualization of the colorectal tumors at 4 and 24 h. Biodistribution at 4 h showed the highest uptake of the tracer in kidneys and sufficient uptake in the tumor, remaining stable for up to 24 h. A single molecular imaging agent, ZW800F-cRGD-[89Zr]Zr-DFO, permits serial PET and NIRF imaging of colorectal tumors, with the latter permitting image-guided treatment intraoperatively. Due to its unique zwitterionic structure, the tracer is rapidly renally cleared and fluorescent background signals are low.

【 授权许可】

CC BY-NC