title: High-uptake areas on positron emission tomography with the hypoxic radiotracer (18)F-FRP170 in glioblastomas include regions retaining proliferative activity under hypoxia.
abstract: OBJECTIVE
  The aim was to evaluate the proliferative activity of high-uptake areas on positron emission tomography (PET) with the hypoxic cell radiotracer, 1-(2-[(18)F]fluoro-1-[hydroxymethyl]ethoxy)methyl-2-nitroimidazole (FRP170).
  
  
  METHODS
  Thirteen patients with glioblastoma underwent FRP170 PET before tumor resection. During surgery, tumor specimens were stereotaxically obtained from regions corresponding to high (high-uptake areas, HUAs) and relatively low (low-uptake areas, LUAs) accumulation of FRP170. We compared immunohistochemical staining for Ki-67 and hypoxia-inducible factor (HIF)-1α between HUA and LUA.
  
  
  RESULTS
  HIF-1α index was significantly higher in HUAs than in LUAs. In contrast, mean Ki-67 indices did not differ significantly between HUAs and LUAs.
  
  
  CONCLUSIONS
  Findings for HIF-1α index clearly indicated that HUAs on FRP170 PET represented hypoxic regions in glioblastoma. However, findings of Ki-67 index suggest that HUAs on FRP170 PET include regions retaining proliferative activity regardless of tissue hypoxia.
authors.affiliation: Department of Neurosurgery, Iwate Medical University, Uchimaru 19-1, Morioka, 020-8505, Japan, tbeppu@iwate-med.ac.jp.
authors.forename: Takaaki
authors.initials: T
authors.lastname: Beppu
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Sasaki
authors.forename: Kazunori
authors.initials: K
authors.lastname: Terasaki
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Saura
authors.forename: Hideki
authors.initials: H
authors.lastname: Mtsuura
authors.forename: Kuniaki
authors.initials: K
authors.lastname: Ogasawara
authors.forename: Makoto
authors.initials: M
authors.lastname: Sasaki
authors.forename: Shigeru
authors.initials: S
authors.lastname: Ehara
authors.forename: Ren
authors.initials: R
authors.lastname: Iwata
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Takai
mesh_terms: D000328:Adult; D000368:Aged; D001921:Brain / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery; D001932:Brain Neoplasms / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery; D005260:Female; D005909:Glioblastoma / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery; D006801:Humans; D000860:Hypoxia / Q000503:physiopathology; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000378:metabolism; D007150:Immunohistochemistry; D019394:Ki-67 Antigen / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009593:Nitroimidazoles; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals
chemical_list: C501635:FRP-170; C497442:HIF1A protein, human; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D019394:Ki-67 Antigen; D009593:Nitroimidazoles; D019275:Radiopharmaceuticals