Evaluation of F-18-labeled amino acid derivatives and [18F]FDG as PET probes in a brain tumor-bearing animal model.

Abstract

UNLABELLED:

2-Deoxy-2-[(18)F]fluoro-d-glucose ([(18)F]FDG) has been extensively used as positron emission tomography (PET) tracer in clinical tumor imaging. This study compared the pharmacokinetics of two (18)F-labeled amino acid derivatives, O-2-[(18)F]fluoroethyl-l-tyrosine (l-[(18)F]FET) and 4-borono-2-[(18)F]fluoro-l-phenylalanine-fructose (l-[(18)F]FBPA-Fr), to that of [(18)F]FDG in an animal brain tumor model.

METHODS:

A self-modified automated PET tracer synthesizer was used to produce no-carrier-added (nca) l-[(18)F]FET. The cellular uptake, biodistribution, autoradiography and microPET imaging of l-[(18)F]FET, l-[(18)F]FBPA-Fr and [(18)F]FDG were performed with F98 glioma cell culture and F98 glioma-bearing Fischer344 rats.

RESULTS:

The radiochemical purity of l-[(18)F]FET was >98% and the radiochemical yield was 50% in average of 16 runs. The uptake of l-[(18)F]FET and l-[(18)F]FBPA-Fr in the F98 glioma cells increased rapidly for the first 5 min and reached a steady-state level after 10 min of incubation, whereas the cellular uptake of [(18)F]FDG kept increasing during the study period. The biodistribution of l-[(18)F]FET, l-[(18)F]FBPA-Fr and [(18)F]FDG in the brain tumors was 1.26+/-0.22, 0.86+/-0.08 and 2.77+/-0.44 %ID/g at 60 min postinjection, respectively, while the tumor-to-normal brain ratios of l-[(18)F]FET (3.15) and l-[(18)F]FBPA-Fr (3.44) were higher than that of [(18)F]FDG (1.44). Both microPET images and autoradiograms of l-[(18)F]FET and l-[(18)F]FBPA-Fr exhibited remarkable uptake with high contrast in the brain tumor, whereas [(18)F]FDG showed high uptake in the normal brain and gave blurred brain tumor images.

CONCLUSION:

Both l-[(18)F]FET and l-[(18)F]FBPA-Fr are superior to [(18)F]FDG for the brain tumor imaging as shown in this study with microPET.

• Authors: Hsin-Ell Wang, Shih-Yen Wu, Chi-Wei Chang, Ren-Shen Liu, Li-Chung Hwang, Te-Wei Lee, Jyh-Cheng Chen, Jeng-Jong Hwang
• Journal: Nuclear medicine and biology (Nucl Med Biol) Vol. 32 Issue 4 Pg. 367-75 (May 2005) ISSN: 0969-8051 [Print] United States
• PMID: 15878506 (Publication Type: Comparative Study, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• 4-borono-2-fluorophenylalaninefructose
• Boron Compounds
• Fluorine Radioisotopes
• Glycopeptides
• O-(2-fluoroethyl)tyrosine
• Radiopharmaceuticals
• Fluorodeoxyglucose F18
• Tyrosine

Topics

• Animals
• Boron Compounds (pharmacokinetics)
• Brain (diagnostic imaging, metabolism)
• Brain Neoplasms (diagnostic imaging, metabolism)
• Cell Line, Tumor
• Disease Models, Animal
• Fluorine Radioisotopes (pharmacokinetics)
• Fluorodeoxyglucose F18 (pharmacokinetics)
• Glioma (diagnostic imaging, metabolism)
• Glycopeptides (pharmacokinetics)
• Metabolic Clearance Rate
• Molecular Probe Techniques
• Organ Specificity
• Positron-Emission Tomography (methods)
• Radiopharmaceuticals (pharmacokinetics)
• Rats
• Tissue Distribution
• Tyrosine (analogs & derivatives, pharmacokinetics)