Xiaoyi Guo1, Nina Zhou1, Zuhua Chen2, Teli Liu1, Xiaoxia Xu1, Xia Lei1, Lin Shen2, Jing Gao2, Zhi Yang3, Hua Zhu4. 1. Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Nuclear Medicine, Peking University Cancer Hospital and Institute, No. 52 Fucheng Rd., Beijing, 100142, China. 2. Department of Gastrointestinal Oncology, Peking University Cancer Hospital and Institute, Beijing, 100142, China. 3. Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Nuclear Medicine, Peking University Cancer Hospital and Institute, No. 52 Fucheng Rd., Beijing, 100142, China. pekyz@163.com. 4. Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Nuclear Medicine, Peking University Cancer Hospital and Institute, No. 52 Fucheng Rd., Beijing, 100142, China. zhuhuananjing@163.com.
Abstract
PURPOSE: Here, we sought to develop a PET radioligand based on trastuzumab labeled with 124I, 124I-trastuzumab, to evaluate its distribution, internal dosimetry, and initial PET images of HER2-positive lesions in gastric cancer (GC) patients. METHODS: In animal studies, micro-PET imaging and bio-distribution were performed to examine the specificity of 124I-trastuzumab in HER2-positive and HER2-negative mouse models. Subsequently, 124I-trastuzumab was applied in human clinic trial. Six gastric cancer patients with metastases underwent 124I-trastuzumab PET imaging, with 18F-FDG PET/CT in each to compare. RESULTS: In animal studies, PET imaging of 124I-trastuzumab showed significant higher tumor uptake than that of 124I-IgG1 in HER2-positive PDX mouse models at 24 h. The low tumor uptake of 124I-trastuzumab in HER2-negative PDX models further confirmed the specificity. In human clinical studies, 18 HER2-positive lesions and 11 HER2-negative lesions were evaluated in PET imaging analysis. The detection sensitivity of 124I-trastuzumab was 100% (18/18) at 24 h. The PET images showed significant difference in tumor uptake between HER2-positive and HER2-negative lesions at 24 h (SUVmax 7.83 ± 0.55 vs. 1.75 ± 0.29, p < 0.0001). Quite striking difference in tumor uptake was observed between 124I-trastuzumab and 18F-FDG (SUVmax 1.75 ± 0.29 vs. 6.46 ± 0.44, p < 0.0001) in HER2-negative lesions, further confirming the specific binding of 124I-trastuzumab in HER2-positive lesions. The radiation-absorbed dose was calculated to be 0.3011 ± 0.005 mSv/MBq. No toxicities or adverse effects were observed in any of the patients. CONCLUSION: The findings described here demonstrated that 124I-trastuzumab was feasible to detect HER2-positive lesions in primary and metastatic gastric cancer patients and to differentiate HER2-positive and HER2-negative lesions quantitatively.
PURPOSE: Here, we sought to develop a PET radioligand based on trastuzumab labeled with 124I, 124I-trastuzumab, to evaluate its distribution, internal dosimetry, and initial PET images of HER2-positive lesions in gastric cancer (GC) patients. METHODS: In animal studies, micro-PET imaging and bio-distribution were performed to examine the specificity of 124I-trastuzumab in HER2-positive and HER2-negative mouse models. Subsequently, 124I-trastuzumab was applied in human clinic trial. Six gastric cancerpatients with metastases underwent 124I-trastuzumab PET imaging, with 18F-FDG PET/CT in each to compare. RESULTS: In animal studies, PET imaging of 124I-trastuzumab showed significant higher tumor uptake than that of 124I-IgG1 in HER2-positive PDX mouse models at 24 h. The low tumor uptake of 124I-trastuzumab in HER2-negative PDX models further confirmed the specificity. In human clinical studies, 18 HER2-positive lesions and 11 HER2-negative lesions were evaluated in PET imaging analysis. The detection sensitivity of 124I-trastuzumab was 100% (18/18) at 24 h. The PET images showed significant difference in tumor uptake between HER2-positive and HER2-negative lesions at 24 h (SUVmax 7.83 ± 0.55 vs. 1.75 ± 0.29, p < 0.0001). Quite striking difference in tumor uptake was observed between 124I-trastuzumab and 18F-FDG (SUVmax 1.75 ± 0.29 vs. 6.46 ± 0.44, p < 0.0001) in HER2-negative lesions, further confirming the specific binding of 124I-trastuzumab in HER2-positive lesions. The radiation-absorbed dose was calculated to be 0.3011 ± 0.005 mSv/MBq. No toxicities or adverse effects were observed in any of the patients. CONCLUSION: The findings described here demonstrated that 124I-trastuzumab was feasible to detect HER2-positive lesions in primary and metastatic gastric cancerpatients and to differentiate HER2-positive and HER2-negative lesions quantitatively.
Authors: George Crișan; Nastasia Sanda Moldovean-Cioroianu; Diana-Gabriela Timaru; Gabriel Andrieș; Călin Căinap; Vasile Chiș Journal: Int J Mol Sci Date: 2022-04-30 Impact factor: 6.208