Therapeutic Efficacy of a ¹⁷⁷ Lu-Labeled DOTA Conjugated <i>α</i> -Melanocyte-Stimulating Hormone Peptide in a Murine Melanoma-Bearing Mouse Model

Abstract

UNLABELLED: The aim of this study was to examine the therapeutic efficacy of (177)Lu-DOTA-Re(Arg(11))CCMSH in the B16/F1 murine melanoma-bearing mouse model. METHODS: (177)Lu-DOTA-Re(Arg(11))CCMSH was prepared in 0.5 M NH(4)OAc at a pH of 5.4. Two (2) treatment groups of 10 melanoma-bearing C57 mice were administrated with 2 x 18.5 MBq and 1 x 37.0 MBq of (177)Lu-DOTA-Re(Arg(11))CCMSH through the tail vein, respectively. One (1) group of 10 melanoma-bearing C57 mice was injected with saline placebos as untreated melanoma-bearing controls. RESULTS: In contrast to the untreated melanoma-bearing control group, (177)Lu-DOTA-Re(Arg(11))CCMSH administration yielded rapid and lasting therapeutic effects in the treatment groups. (177)Lu-DOTA-Re(Arg(11))CCMSH treatment decreased the tumor growth rate and significantly (p > 0.05) prolonged the survival time of melanoma-bearing C57 mice. Treatment with 2 x 18.5 MBq or 1 x 37.0 MBq of (177)Lu-DOTA-Re(Arg(11))CCMSH significantly extended the mean survival of tumor-bearing mice from 13.3 to 15.1 and 16.2 days, respectively. (177)Lu-DOTA-Re(Arg(11))CCMSH treatment produced no observed acute renal toxicity. CONCLUSIONS: The therapy study results revealed that (177)Lu-DOTA-Re(Arg(11))CCMSH yielded quantitative therapeutic effects in B16/F1 melanoma-bearing mice and appeared to be a promising radiolabeled peptide for the targeted radionuclide therapy of melanoma.