Molecular Imaging and Biology

, Volume 20, Issue 2, pp 200–204 | Cite as

Translocator Protein PET Imaging in a Preclinical Prostate Cancer Model

  • Mohammed N. Tantawy
  • H. Charles Manning
  • Todd E. Peterson
  • Daniel C. Colvin
  • John C. Gore
  • Wenfu Lu
  • Zhenbang Chen
  • C. Chad Quarles
Brief Article
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Abstract

Purpose

The identification and targeting of biomarkers specific to prostate cancer (PCa) could improve its detection. Given the high expression of translocator protein (TSPO) in PCa, we investigated the use of [18F]VUIIS1008 (a novel TSPO-targeting radioligand) coupled with positron emission tomography (PET) to identify PCa in mice and to characterize their TSPO uptake.

Procedures

Ptenpc−/−, Trp53pc−/− prostate cancer-bearing mice (n = 9, 4–6 months old) were imaged in a 7T MRI scanner for lesion localization. Within 24 h, the mice were imaged using a microPET scanner for 60 min in dynamic mode following a retro-orbital injection of ~ 18 MBq [18F]VUIIS1008. Following imaging, tumors were harvested and stained with a TSPO antibody. Regions of interest (ROIs) were drawn around the tumor and muscle (hind limb) in the PET images. Time-activity curves (TACs) were recorded over the duration of the scan for each ROI. The mean activity concentrations between 40 and 60 min post radiotracer administration between tumor and muscle were compared.

Results

Tumor presence was confirmed by visual inspection of the MR images. The uptake of [18F]VUIIS1008 in the tumors was significantly higher (p < 0.05) than that in the muscle, where the percent injected dose per unit volume for tumor was 7.1 ± 1.6 % ID/ml and that of muscle was < 1 % ID/ml. In addition, positive TSPO expression was observed in tumor tissue analysis.

Conclusions

The foregoing preliminary data suggest that TSPO may be a useful biomarker of PCa. Therefore, using TSPO-targeting PET ligands, such as [18F]VUIIS1008, may improve PCa detectability and characterization.

Key Words

Translocator protein Prostate cancer PET 

Notes

Acknowledgments

This work was supported by DOD W81XWH-12-1-0245 and R01 CA163806. The microPET Focus 220 was funded by NIH 1S10 RR017858, and the Inveon microPET/CT was funded by NIH 1S10 OD016245.

Compliance with Ethical Standards

Conflict of Interest

The authors declare that they have no conflict of interest.

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Copyright information

© World Molecular Imaging Society 2017

Authors and Affiliations

  • Mohammed N. Tantawy
    • 1
    • 2
  • H. Charles Manning
    • 1
    • 2
    • 3
    • 4
  • Todd E. Peterson
    • 1
    • 2
  • Daniel C. Colvin
    • 1
  • John C. Gore
    • 1
    • 2
  • Wenfu Lu
    • 5
  • Zhenbang Chen
    • 5
  • C. Chad Quarles
    • 6
  1. 1.Vanderbilt University Institute of Imaging Science (VUIIS), Vanderbilt University Medical CenterNashvilleUSA
  2. 2.Department of Radiology and Radiological SciencesVanderbilt University Medical CenterNashvilleUSA
  3. 3.Vanderbilt-Ingram Cancer CenterVanderbilt University Medical CenterNashvilleUSA
  4. 4.Program in Chemical and Physical BiologyVanderbilt University Medical CenterNashvilleUSA
  5. 5.Department of Biochemistry and Cancer BiologyMeharry Medical CollegeNashvilleUSA
  6. 6.Imaging Research, Barrow Neurological InstitutePhoenixUSA

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