Author/Authors :
Shamshirian, Danial Department of Radiopharmacy - School of Pharmacy, Tehran University of Medical Sciences, Tehran , Hajiramazanali, Maliheh Department of Radiopharmacy - School of Pharmacy, Tehran University of Medical Sciences, Tehran , Erfani, Mostafa Radiation Application Research School - Nuclear Science and Technology Research Institute (NSTRI), Tehran , Beiki, Davood Research Center for Nuclear Medicine, Tehran University of Medical Sciences, Tehran , Fallahi, Babak Research Center for Nuclear Medicine, Tehran University of Medical Sciences, Tehran
Abstract :
Melanocortin-1 (MC1) receptor is an attractive melanoma-specific target for the development
of α-MSH peptide based imaging and therapeutic agents. In this work a new lactam bridge
α-MSH analogue was synthesized and radiolabeled with 99mTc via HYNIC chelator and
tricine as co-ligand. Also, stability in human serum, receptor bound internalization and tissue
biodistribution in tumor bearing nude mice were thoroughly investigated. Radiolabeling with
99mTc was performed at high specific activities (163MBq/nmol) with an acceptable labeling
yield (>98%). The radioligand showed specific internalization into B16/F10 cells (13.35
± 0.9% at 4 h). In biodistribution studies, a receptor-specific uptake was observed in MC1
receptor positive organ so that after 4 h the tumor uptake was 4.51 ± 0.11 % ID/g. Predominant
renal excretion pathway with a highest accumulation of activity in tumor was observed for this
radiopeptide. Obtained results show that the new designed labeled peptide conjugate can be a
suitable candidate for diagnosis of metastatic melanomas
Keywords :
α-MSH , 99mTc , Tricine , HYNIC , Radiopeptide
