Synthesis and Biochemical Evaluation of Samarium-153 Oxide Nanoparticles Functionalized with iPSMA-Bombesin Heterodimeric Peptide.

ABSTRACT

Developments in the design of lanthanide oxide nanoparticles (NPs) have unleashed a wide variety of biomedical applications. Several types of hepatic cancer cells overexpress two proteins the gastrin-releasing peptide receptor (GRPr), which specifically recognizes the bombesin (BN) peptide, and the prostate-specific membrane antigen (PSMA), which specifically binds to several peptides that inhibit its activity (iPSMA). This research synthesized and physicochemically characterized Sm2O3 nanoparticles functionalized with the iPSMA-BN heterodimeric peptide and studied the effects on their structural, biochemical and preclinical properties after activation by neutron irradiation for possible use in molecular dual-targeted radiotherapy of hepatocellular carcinoma. The Sm2O3 NPs were synthesized by the precipitation-calcination method and functionalized with iPSMA-BN peptide using the DOTA macrocycle as a linking agent. Analysis of physicochemical characterization via TEM, EDS, XRD, UV-Vis, FT-IR, DSL, and zeta potential results showed the formation of Sm2O3-iPSMA-BN NPs (94.23 ± 5.98 nm), and their physicochemical properties were not affected after neutron activation. The nanosystem showed a high affinity with respect to PSMA and GRPr in HepG2 cells ( Kd = 6.6 ± 1.6 nM) and GRPr in PC3 cells ( Kd = 10.6 ± 1.9 nM). 153Sm2O3-iPSMA-BN NPs exhibited radioluminescent properties, making possible in vivo optical imaging of their biodistribution in mice. The results obtained from this research support further preclinical studies designed to evaluate the dosimetry and therapeutic efficacy of 153Sm2O3-iPSMA-BN nanoparticles for in vivo imaging and molecular dual-targeted radiotherapy of liver tumors overexpressing PSMA and/or GRPr proteins.