title: Further characterization of the epidermal growth factor receptor ligand 11C-PD153035.
abstract: BACKGROUND
  (11)C-4-N-(3-bromoanilino)-6,7-dimethoxyquinazoline ((11)C-PD153035) has been reported as a tracer for imaging human tumors that overexpress epidermal growth factor receptor (EGFR). However it is still unclear whether (11)C-PD153035 uptake correlates with EGFR expression levels. The objective of this study was to investigate the relationship between (11)C-PD153035 accumulation and EGFR expression levels.
  
  
  METHODS
  Synthesis of (11)C-PD153035 was performed in the Tracerlab FXc system. Accumulation of (11)C-PD153035 by MDA-MB-468, A549 and MDA-MB-231 cells was measured in vitro. There were six tumor-bearing mice in each group. (11)C-PD153035 uptake in tumors was determined by positron emission tomography/computed tomography (PET/CT). Tumor/normal muscle tissue (T/NT) analysis in PET images was applied to quantify the PET data. Sixty minutes after PET/CT scanning, the nude mice were sacrificed and the tumors were excised. The (11)C-PD153035 accumulation in different tumors was determined by a gamma counter.
  
  
  RESULTS
  Close correlation existed between the uptake and the level of EGFR expression both in vitro and ex vivo (r(2) = 0.72, P < 0.001; r(2) = 0.63, P = 0.003). When the static T/NT analysis method was applied to analyze the PET data, the observed correlation was again excellent (r(2) = 0.70, P = 0.001).
  
  
  CONCLUSIONS
  The uptake of PET tracer (11)C-PD153035 closely correlates with the EGFR expression levels in tumor cells. (11)C-PD153035 has the potential to yield useful information for both cancer diagnosis and therapy.
authors.affiliation: Medical School of Shandong University, Jinan 250012, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
authors.forename: Jin-ming
authors.initials: JM
authors.lastname: Yu
authors.forename: Guo-ren
authors.initials: GR
authors.lastname: Yang
authors.forename: Xian-rang
authors.initials: XR
authors.lastname: Song
authors.forename: Xiao-rong
authors.initials: XR
authors.lastname: Sun
authors.forename: Shu-qiang
authors.initials: SQ
authors.lastname: Zhao
authors.forename: Xing-wu
authors.initials: XW
authors.lastname: Wang
authors.forename: Wei
authors.initials: W
authors.lastname: Zhao
mesh_terms: D000818:Animals; D002250:Carbon Radioisotopes; D045744:Cell Line, Tumor; D066246:ErbB Receptors / Q000032:analysis* / Q000378:metabolism; D005260:Female; D006801:Humans; D008024:Ligands; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D049268:Positron-Emission Tomography; D011799:Quinazolines / Q000378:metabolism*
chemical_list: D002250:Carbon Radioisotopes; D008024:Ligands; D011799:Quinazolines; D066246:ErbB Receptors; C088860:4-((3-bromophenyl)amino)-6,7-dimethoxyquinazoline