@misc{oai:repo.qst.go.jp:00065772, author = {Xie, Lin and Yui, Joji and Fujinaga, Masayuki and Hatori, Akiko and Yamasaki, Tomoteru and Kumata, Katsushi and Wakizaka, Hidekatsu and Kawamura, Kazunori and Zhang, Ming-Rong and 謝 琳 and 由井 譲二 and 藤永 雅之 and 羽鳥 晶子 and 山崎 友照 and 熊田 勝志 and 脇坂 秀克 and 河村 和紀 and 張 明栄}, month = {Nov}, note = {Purpose: Oncoimaging using positron emission tomography (PET) with a specific radioprobe would facilitate individualized cancer management. Evidence indicates that ectopically expressed metabotropic glutamate 1 (mGlu1) receptor independently induces melanocyte carcinogenesis, and it is therefore becoming an important target for personalized diagnosis and treatment strategies for melanomas. Here, we constructed an oncoprotein-based PET imaging platform in melanomas for noninvasive visualization and quantification of mGlu1 with a novel mGlu1-specific radioprobe, 4-18F-fluoro-N-[4-[6-(isopropylamino)pyrimidin-4-yl]-1,3-thiazol-2-yl]-N-methylbenzamide (18F-FITM). Methods: Cellular affinity and specific binding of 18F-FITM were assayed in mGlu1-positive B16F1 and B16F10 melanoma cells and in mGlu1-negative Hepa1-6 hepatoma cells (control). 18F-FITM PET/CT was performed to visualize and quantify mGlu1 in tumor-bearing mice with subcutaneous or pulmonary metastatic melanomas. The mGlu1 protein expression in tumors was further examined by immunohistochemistry. Results: High cellular affinity and specific binding in tumor tissue was seen with 18F-FITM in the mGlu1-positive B16F1 and B16F10 melanomas but not in the control. The specific binding closely reflected the mGlu1 protein expression. In tumor-bearing mice, 18F-FITM PET/CT clearly showed dense and specific uptake of radioactivity in B16F1 (7.46 ± 0.30 %ID/g) and B16F10 (5.75 ± 0.27 %ID/g) tumor grafts compared with Hepa1-6 tumor grafts (0.47 ± 0.08 %ID/g), at 120 min after radioprobe injection respectively. In the mice with pulmonary metastatic melanoma grafts, there was intense and definite uptake at the tumor sites where CT confirmed extensive tumors, with very low background signals. Conclusions: 18F-FITM showed potential as a radioprobe for mGlu1 in melanomas and melanoma metastasis. The 18F-FITM PET imaging platform, as a noninvasive personalized diagnostic tool, is expected to open a new avenue for defining individualized therapeutic strategies, clinical trials, patient management and understanding mGlu1-triggered oncologic events in melanomas., The 54th Annual Scientific Meeting of the Japanese Society for Nuclear Medicine Japan-China Nuclear Medicine Exchange Seminar}, title = {Oncoimaging of melanoma by targeted ectopic metabotropic glutamate 1 receptor with a positron emission tomography radioprobe 18F-FITM}, year = {2014} }