Tumor uptake study of 18F-labeled N-acetylneuraminic acids.
In order to develop positron-emitting tracers for imaging metabolic functions of tumors with positron emission tomography, tumor uptake of N-acetyl-3-[18F]fluoroneuraminic acid and N-acetyl-2-deoxy-2,3-di-[18F]fluoroneuraminic acid was investigated in mice or rats. The two tracers showed similar tissue distribution patterns. After i.v. injection of each tracer into mice with an FM3A tumor, the radioactivity was very rapidly cleared from normal and tumor tissues. Only tumor-to-brain and tumor-to-muscle uptake ratios were greater than 1.0 for 2 h. In 7 types of tumor models, no selective tumor uptake of tracers was observed 30 min after injection. The metabolic alteration rate of N-acetyl-3-[18F]fluoroneuraminic acid in FM3A, liver and kidney was very slow. Neither tracer may be suitable for tumor imaging in vivo.
Ishiwata
K
K
Division of Radiopharmaceutical Chemistry, Faculty of Agriculture, Tohoku University, Sendai, Japan.
Ido
T
T
Nakajima
T
T
Ohrui
H
H
Kijima-Suda
I
I
Itoh
M
M
D000818:Animals; D005462:Fluorine Radioisotopes; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D009374:Neoplasms, Experimental / Q000000981:diagnostic imaging* / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D012794:Sialic Acids / Q000138:chemical synthesis* / Q000493:pharmacokinetics; D014018:Tissue Distribution; D014055:Tomography, Emission-Computed
D005462:Fluorine Radioisotopes; D012794:Sialic Acids; C065263:N-acetyl-2-deoxy-2,3-difluoroneuraminic acid; C065264:N-acetyl-3-fluoroneuraminic acid