3-O-Methyl-6-18F-Fluoro-l-Dopa, a New Tumor Imaging Agent: Investigation of Transport Mechanism In Vitro

Journal of Nuclear Medicine

Beate Pawelke¹  Frank Fuechtner¹  Bettina Beuthien-Baumann¹  Joerg Kotzerke¹  Bernd Johannsen¹  Jens Pietzsch¹  Ralf Bergmann¹ 

关键词: amino acid transport;    ¹⁸F;    PET;    radiotracer;   

DOI  :  

学科分类：医学（综合）

来源: Society of Nuclear Medicine

【 摘 要 】

18F-Labeled amino acids represent a promising class of imaging agents in tumors, particularly brain tumors. However, the determination of their potential to image peripheral tumors, possibly depending on individual transport characteristics, still remains an area of investigation. The present study investigated the transport mechanism for 3-O-methyl-6-18F-fluoro-l-dopa (OMFD), a novel 18F-labeled phenylalanine derivative, into tumor cells. Methods: OMFD has routinely and reliably been prepared for clinical use in 20%–25% radiochemical yield (decay corrected, related to 18F-F2) using 6-18F-fluoro-l-3,4-dihydroxyphenylalanine preparation devices with minor modifications. In vitro uptake assays with HT-29 (human colon adenocarcinoma) cells, FaDu (squamous cell carcinoma) cells, and RBE4 (immortalized rat brain endothelial) cells were performed with OMFD under physiologic amino acid concentrations without and with the competitive transport inhibitors 2-aminobicyclo-[2,2,1]-heptane-2-carboxylic acid and α-(methylamino)isobutyric acid plus serine and without or with Na+. Results: Transport inhibition experiments using specific competitive inhibitors demonstrated that uptake of OMFD in all cell lines tested was mediated mainly by the sodium-independent high-capacity amino acid transport systems. The highest OMFD uptake was in FaDu cells. Conclusion: OMFD seems to be a promising PET tracer for imaging of amino acid transport in tumors.

【 授权许可】

Unknown