Metastatic breast cancer is incurable. The goal of this study was to develop a positron emission tomography (PET)/near-infrared fluorescent (NIRF) probe for imaging CD105 expression in breast cancer experimental lung metastasis. TRC105, a chimeric anti-CD105 antibody, was dual-labeled with a NIRF dye (IRDye 800CW) and
89Zr to yield
89Zr-Df-TRC105-800CW. Luciferase-transfected 4T1 murine breast cancer cells were in
jected intravenously into female mice to establish the tumor model. Bioluminescence imaging (BLI) was carried out to noninvasively monitor the lung tumor burden. PET imaging revealed that 4T1 lung tumor uptake of
89Zr-Df-TRC105-800CW was 8.7 卤 1.4, 10.9 卤 0.5, and 9.7 卤 1.1% ID/g at 4, 24, and 48 h postin
jection (
n = 4), with excellent tumor contrast. Biodistribution studies, blocking, control studies with
89Zr-Df-cetuximab-800CW, ex vivo BLI/PET/NIRF imaging, and histology all confirmed CD105 specificity of the tracer. Broad clinical potential of TRC105-based agents was shown in many tumor types, which also enabled early detection of small metastasis and intraoperative guidance for tumor removal.
Keywords:
breast cancer;
lung metastasis;
positron emission tomography (PET);
near-infrared fluorescence (NIRF);
tumor angiogenesis;
CD105 (endoglin);
89Zr