Metabolic fates of 2'-deoxy-5-[18F]fluorouridine in tumor-bearing mice and human plasma.
The metabolic fate of 2'-deoxy-5-[18F]fluorouridine ([18F]FdUrd), a useful positron emission tomography (PET) tracer of nucleic acid metabolism in tumors, was investigated in mice and humans. A rapid increase in labeled catabolites was found in mouse and human plasma. In mouse FM3A mammary carcinoma, the corresponding catabolites were also detected in addition to metabolites which were activated by the nucleic acid metabolism. From a biodistribution study of beta-[3H]alanine, alpha-[18F]fluoro-beta-alanine, a major catabolite, was assumed to be taken up twice as much by tumor than by the brain. Nucleic acid metabolism in brain tumors by [18F]FdUrd-PET may be assessed using normal brain regions as a reference.
Ishiwata
K
K
Division of Radiopharmaceutical Chemistry, Tohoku University, Sendai, Japan.
Sato
K
K
Kameyama
M
M
Yoshimoto
T
T
Ido
T
T
D000818:Animals; D001711:Biotransformation; D001932:Brain Neoplasms / Q000378:metabolism; D005467:Floxuridine / Q000097:blood / Q000493:pharmacokinetics*; D005462:Fluorine Radioisotopes; D006801:Humans; D008297:Male; D008325:Mammary Neoplasms, Experimental / Q000378:metabolism; D051379:Mice; D008809:Mice, Inbred C3H; D008815:Mice, Inbred Strains; D009374:Neoplasms, Experimental / Q000378:metabolism*; D014018:Tissue Distribution
D005462:Fluorine Radioisotopes; D005467:Floxuridine; C025034:doxifluridine