Gallium-68-labeled DOTA-rhenium-cyclized α-melanocyte-stimulating hormone analog for imaging of malignant melanoma

Wei, Lihui; Miao, Yubin; Gallazzi, Fabio; Quinn, Thomas P.; Welch, Michael J.; Vāvere, Amy L.; Lewis, Jason S.

doi:10.1016/j.nucmedbio.2007.07.003

« Previous Next »Nuclear Medicine and Biology
Volume 34, Issue 8 , Pages 945-953, November 2007

Gallium-68-labeled DOTA-rhenium-cyclized α-melanocyte-stimulating hormone analog for imaging of malignant melanoma

Lihui Wei
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
Yubin Miao
- Department of Biochemistry, University of Missouri-Columbia, Columbia, MO 65212, USA
Fabio Gallazzi
- Department of Biochemistry, University of Missouri-Columbia, Columbia, MO 65212, USA
Thomas P. Quinn
- Department of Biochemistry, University of Missouri-Columbia, Columbia, MO 65212, USA
Michael J. Welch
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
- Alvin J. Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO 63110, USA
Amy L. Vāvere
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
Jason S. Lewis
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110, USA
- Alvin J. Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO 63110, USA
- Corresponding author. Mallinckrodt Institute of Radiology, Washington University School of Medicine, Campus Box 8225, St. Louis, MO 63110, USA. Tel.: +1 314 362 4696; fax: +1 314 362 9940.

Received 10 April 2007; received in revised form 7 June 2007; accepted 3 July 2007. published online 03 September 2007.

Abstract

Introduction

Diagnosis of malignant melanoma is critical, since a patient's prognosis is poor. Previous studies have shown that ⁶⁴Cu- and ⁸⁶Y-DOTA-ReCCMSH(Arg¹¹) have the potential for early detection of malignant melanoma by exploiting the sensitivity and high resolution of positron emission tomography (PET). This encouraged us to investigate DOTA-ReCCMSH(Arg¹¹) labeled with another β⁺-emitting radionuclide, ⁶⁸Ga.

Methods

DOTA-ReCCMSH(Arg¹¹) was successfully labeled with ⁶⁸Ga at pH 3.8–4 at 85°C. Acute biodistribution and small-animal PET imaging studies were performed in mice bearing B16/F1 melanoma tumor.

Results

Biodistribution studies showed moderate receptor-mediated tumor uptake, fast nontarget organ clearance and high tumor to nontarget tissue ratios. Preadministration of d-lysine significantly reduced kidney uptake without affecting the uptake of the agent in the tumor. Small-animal PET images showed that the tumor could be clearly visualized at all time points examined (0.5–2 h) with the standardized uptake value analysis following a similar trend as the biodistribution data.