title: Multimodality Imaging of Cancer Superoxide Anion Using the Small Molecule Coelenterazine.
abstract: OBJECTIVE
  We evaluated the small molecule coelenterazine as a potential reporter of cancer-associated superoxide anion in cell culture and in mice.
  
  
  METHODS
  The superoxide anion concentrations of various cancer cell lines were quantified by coelenterazine chemiluminescence in vitro. Coelenteramide fluorescence was detected via flow cytometry and fluorescent microscopy. Coelenterazine was used for the in vivo detection of cancer-associated superoxide anion using the 4T1 breast adenocarcinoma mouse model.
  
  
  RESULTS
  Various cell lines in culture demonstrated different superoxide anion concentrations, with a signal range of 3.15 ± 0.06 to 11.80 ± 0.24 times that of background. In addition to chemiluminescent detection of coelenterazine, we demonstrated fluorescent detection of coelenteramide within the cytoplasm of cells. 4T1 murine mammary adenocarcinoma tumors in mice demonstrated significantly higher 2.13 ± 0.19-fold coelenterazine-based chemiluminescence than that of surrounding normal tissues.
  
  
  CONCLUSIONS
  Collectively, our results indicate that coelenterazine can be used to assay superoxide anion concentrations in cultured cancer cells and in tumors growing in mice.
authors.affiliation: Department of Biology, Stanford University, 318 Campus Drive, Stanford, CA, 94305, USA.|Department of Pediatrics, Stanford University, 318 Campus Drive, Stanford, CA, 94305, USA.
authors.forename: Laura L
authors.initials: LL
authors.lastname: Bronsart
authors.affiliation: Department of Pediatrics, Stanford University, 318 Campus Drive, Stanford, CA, 94305, USA.
authors.forename: Christian
authors.initials: C
authors.lastname: Stokes
authors.affiliation: Department of Pediatrics, Stanford University, 318 Campus Drive, Stanford, CA, 94305, USA. ccontag@stanford.edu.|Departments of Radiology, Microbiology and Immunology, Stanford University, 318 Campus Drive, Stanford, CA, 94305, USA. ccontag@stanford.edu.
authors.forename: Christopher H
authors.initials: CH
authors.lastname: Contag
mesh_terms: D000818:Animals; D005260:Female; D005434:Flow Cytometry; D006367:HeLa Cells; D006801:Humans; D007093:Imidazoles / Q000032:analysis*; D008807:Mice, Inbred BALB C; D008856:Microscopy, Fluorescence; D064847:Multimodal Imaging / Q000379:methods*; D009369:Neoplasms / Q000378:metabolism*; D011719:Pyrazines / Q000032:analysis*; D054852:Small Molecule Libraries / Q000032:analysis*; D013481:Superoxides / Q000032:analysis* / Q000378:metabolism*
chemical_list: D007093:Imidazoles; D011719:Pyrazines; D054852:Small Molecule Libraries; D013481:Superoxides; C017144:coelenterazine
keywords: Bioluminescence; Cancer; Chemiluminescence; Coelenteramide; Coelenterazine; Fluorescence; Reactive oxygen species; Superoxide anion