Intraoperative Near-Infrared Fluorescence Tumor Imaging with Vascular Endothelial Growth Factor and Human Epidermal Growth Factor Receptor 2 Targeting Antibodies

Abstract

Fluorescence imaging is currently attracting much interest as a method for intraoperative tumor detection, but most current tracers lack tumor specificity. Therefore, this technique can be further improved by tumor-specific detection. With tumortargeted antibodies bound to a radioactive label, tumor-specific SPECT or PET is feasible in the clinical setting. The aim of the present study was to apply antibody-based tumor detection to intraoperative optical imaging, using preclinical in vivo mouse models. Methods: Anti-vascular endothelial growth factor (VEGF) antibody bevacizumab and anti-human epidermal growth factor receptor (HER) 2 antibody trastuzumab were labeled with the near-infrared (NIR) fluorescence dye IRDye 800CW. Tumor uptake of the fluorescent tracers and their 89 Zr-labeled radioactive counterparts for PET was determined in human xenograft-bearing athymic mice during 1 wk after tracer injection, followed by ex vivo biodistribution and pathologic examination. Intraoperative imaging of fluorescent VEGF-or HER2-positive tumor lesions was performed in subcutaneous tumors and in intraperitoneal dissemination tumor models. Results: Tumorto-background ratios, with fluorescent imaging, were 1.93 6 0.40 for bevacizumab and 2.92 6 0.29 for trastuzumab on day 6 after tracer injection. Real-time intraoperative imaging detected tumor lesions at even the submillimeter level in intraperitoneal dissemination tumor models. These results were supported by standard histology, immunohistochemistry, and fluorescence microscopy analyses. Conclusion: NIR fluorescence-labeled antibodies targeting VEGF or HER2 can be used for highly specific and sensitive detection of tumor lesions in vivo. These preclinical findings encourage future clinical studies with NIR fluorescence-labeled tumor-specific antibodies for intraoperative-guided surgery in cancer patients.

Molecular Fluorescence Endoscopy Targeting Vascular Endothelial Growth Factor A for Improved Colorectal Polyp Detection

“…3C). For bevacizumab-800CW, the fluorescent signal was mainly located in the tumor stroma and surrounding the tumor blood vessels, corresponding with our previous observations for 89 Zr-and 111 In-labeled bevacizumab (14,21). A more homogeneous distribution was seen for cetuximab-800CW in the tumor lesions, with membranous and cytoplasmic localization of the NIR fluorescence signals (22).…”

“…were labeled with IRDye800CW-NHS (LI-COR Biosciences) (14,15). This NIR fluorescent dye underwent extensive toxicity testing and is a good-manufacturing-practice-compliant compound, registered at the U.S. Food and Drug Administration (16,17).…”

89Zr-Bevacizumab PET Imaging in Primary Breast Cancer

“…This technique has already been tested in human xenograft-bearing athymic mice, detecting tumor lesions in vivo with high sensitivity and specificity. IRDye 800CW-labeled bevacizumab revealed submillimeter lesions with a clinical intraoperative fluorescence camera (26). Recently, we started a study with IRDye 800CW-labeled bevacizumab in early breast cancer (NCT01508572).…”

Optical Imaging of Renal Cell Carcinoma with Anti–Carbonic Anhydrase IX Monoclonal Antibody Girentuximab

“…Terwisscha van Scheltinga et al (19) reported specific and sensitive detection of tumor lesions in vivo when they used fluorescence-labeled antibodies targeting vascular endothelial growth factor or human epidermal growth factor 2 in a breast cancer xenograft mouse model. The animals in that study received a second injection with the same antibodies labeled with a positron-emitting radionuclide, 89 Zr, to enable a comparison between fluorescence imaging and PET imaging.…”