title: Preliminary in vivo evaluation of [131I]-2-iodo-D-phenylalanine as a potential radionuclide therapeutic agent in R1M-fluc rhabdomyosarcoma tumor-bearing NuNu mice using bioluminescent imaging.
abstract: BACKGROUND
  Carrier-added [(123)I]-2-iodo-D-phenylalanine (CA [(123)I]-2-I-D-Phe) was previously found to have a preferential retention in tumors with a high tumor background contrast in animal models. A previous human dosimetry study demonstrated a favorable biodistribution and radiation burden in human subjects.
  
  
  OBJECTIVE
  The aim of this study was to investigate the potential of CA [(131)I]-2-I-D-Phe as an agent for radionuclide therapy.
  
  
  METHODS
  Sixty (60) nude athymic mice were inoculated subcutaneously with firefly luciferase-transduced R1M rhabdomyosarcoma cells. The mice in the therapy group were injected intravenously (i.v.) with 148 MBq [(131)I]-2-I-D-Phe (432 GBq/mmol) in kit solution. Controls were injected with kit solution without radioactivity, with physiological saline, or with 148 MBq [(131)I](-) in physiological saline. Tumor growth was quantified using bioluminescent imaging and caliper measurements.
  
  
  RESULTS
  [(131)I]-2-I-D-Phe clearly reduced tumor growth in the treated mice compared with the control groups. A tumor growth-rate reduction of at least 33% was found for mice receiving a therapeutic dose. There were no serious adverse side-effects of the therapy.
  
  
  CONCLUSIONS
  In conclusion, i.v. injection of CA 148 MBq [(131)I]-2-I-D-Phe specifically reduces tumor growth in athymic nude mice without relevant side-effects on the animals' health.
authors.affiliation: Laboratory of Radiopharmacy, KUL, Leuven, Belgium. matthias.bauwens@pharm.kuleuven.be
authors.forename: Matthias
authors.initials: M
authors.lastname: Bauwens
authors.forename: Lena
authors.initials: L
authors.lastname: Wimana
authors.forename: Marleen
authors.initials: M
authors.lastname: Keyaerts
authors.forename: Cindy
authors.initials: C
authors.lastname: Peleman
authors.forename: Tony
authors.initials: T
authors.lastname: Lahoutte
authors.forename: Ken
authors.initials: K
authors.lastname: Kersemans
authors.forename: Sarah
authors.initials: S
authors.lastname: Snykers
authors.forename: Mathieu
authors.initials: M
authors.lastname: Vinken
authors.forename: John
authors.initials: J
authors.lastname: Mertens
authors.forename: Axel
authors.initials: A
authors.lastname: Bossuyt
mesh_terms: D000818:Animals; D006801:Humans; D007457:Iodine Radioisotopes; D008156:Luciferases / Q000378:metabolism*; D008163:Luminescent Measurements; D051379:Mice; D008819:Mice, Nude; D010649:Phenylalanine / Q000031:analogs & derivatives*; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D012208:Rhabdomyosarcoma / Q000000981:diagnostic imaging*; D014018:Tissue Distribution; D014407:Tumor Cells, Cultured; D023041:Xenograft Model Antitumor Assays
chemical_list: C496694:2-iodophenylalanine; D007457:Iodine Radioisotopes; D019275:Radiopharmaceuticals; D010649:Phenylalanine; D008156:Luciferases