title: The Synthesis and Evaluations of the (6 8) Ga-Lissamine Rhodamine B (LRB) as a New Radiotracer for Imaging Tumors by Positron Emission Tomography.
abstract: OBJECTIVE
  The aim of this study is to synthesize and evaluate (68)Ga-labeled Lissamine Rhodamine B (LRB) as a new radiotracer for imaging MDA-MB-231 and MCF-7 cells induced tumor mice by positron emission tomography (PET).
  
  
  METHODS
  Firstly, we performed the radio synthesis and microPET imaging of (68)Ga(DOTA-LRB) in athymic nude mice bearing MDA-MB-231 and MCF-7 human breast cancer xenografts. Additionally, the evaluations of (18)F-fluorodeoxyglucose (FDG), as a glucose metabolism radiotracer for imaging tumors in the same xenografts, have been conducted as a comparison.
  
  
  RESULTS
  The radiochemical purity of (68)Ga(DOTA-LRB) was >95%. MicroPET dynamic imaging revealed that the uptake of (68)Ga(DOTA-LRB) was mainly in normal organs, such as kidney, heart, liver, and brain and mainly excreted from kidney. The MDA-MB-231 and MCF-7 tumors were not clearly visible in PET images at 5, 15, 30, 40, 50, and 60 min after injection of (68)Ga(DOTA-LRB). The tumor uptake values of (18)F-FDG were 3.79 ± 0.57 and 1.93 ± 0.48%ID/g in MDA-MB-231 and MCF-7 tumor xenografts, respectively.
  
  
  CONCLUSIONS
  (68)Ga(DOTA-LRB) can be easily synthesized with high radiochemical purity and stability; however, it may be not an ideal PET radiotracer for imaging of MDR-positive tumors.
authors.affiliation: Department of Nuclear Medicine, The First Hospital of China Medical University, Shenyang 110001, China.
authors.forename: Xuena
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Nuclear Medicine, The First Hospital of China Medical University, Shenyang 110001, China.
authors.forename: Yafu
authors.initials: Y
authors.lastname: Yin
authors.affiliation: Department of Nuclear Medicine, The First Hospital of China Medical University, Shenyang 110001, China.
authors.forename: Bulin
authors.initials: B
authors.lastname: Du
authors.affiliation: Department of Nuclear Medicine, The First Hospital of China Medical University, Shenyang 110001, China.
authors.forename: Na
authors.initials: N
authors.lastname: Li
authors.affiliation: Department of Nuclear Medicine, The First Hospital of China Medical University, Shenyang 110001, China.
authors.forename: Yaming
authors.initials: Y
authors.lastname: Li
mesh_terms: D000818:Animals; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism / Q000473:pathology; D003287:Contrast Media / Q000138:chemical synthesis / Q000494:pharmacology*; D019788:Fluorodeoxyglucose F18 / Q000494:pharmacology; D006801:Humans; D061986:MCF-7 Cells; D051379:Mice; D049268:Positron-Emission Tomography / Q000379:methods*; D019275:Radiopharmaceuticals / Q000494:pharmacology; D012235:Rhodamines / Q000138:chemical synthesis / Q000494:pharmacology*; D014018:Tissue Distribution; D023041:Xenograft Model Antitumor Assays
chemical_list: D003287:Contrast Media; D019275:Radiopharmaceuticals; D012235:Rhodamines; D019788:Fluorodeoxyglucose F18; C022027:lissamine rhodamine B