BACKGROUND: Currently, the diagnosis and treatment of neuroblastomas-the most frequent solid tumors in children-exploit the norepinephrine transporter (hNET) via radiolabeled norepinephrine analogs. We aim to develop a nanomedicine-based strategy towards precision therapy by targeting hNET cell-surface protein with hNET-derived homing peptides. RESULTS: The peptides (seq. GASNGINAYL and SLWERLAYGI) were shown to bind high-resolution homology models of hNET in silico. In particular, one unique binding site has marked the sequence and structural similarities of both peptides, while most of the contribution to the interaction was attributed to the electrostatic energy of Asn and Arg (< - 228 kJ/mol). The peptides were comprehensively characterized by computational and spectroscopic methods showing ~ 21% β-sheets/aggregation for GASNGINAYL and ~ 27% α-helix for SLWERLAYGI. After decorating 12-nm ferritin-based nanovehicles with cysteinated peptides, both peptides exhibited high potential for use in actively targeted neuroblastoma nanotherapy with exceptional in vitro biocompatibility and stability, showing minor yet distinct influences of the peptides on the global expression profiles. Upon binding to hNET with fast binding kinetics, GASNGINAYLC peptides enabled rapid endocytosis of ferritins into neuroblastoma cells, leading to apoptosis due to increased selective cytotoxicity of transported payload ellipticine. Peptide-coated nanovehicles significantly showed higher levels of early apoptosis after 6 h than non-coated nanovehicles (11% and 7.3%, respectively). Furthermore, targeting with the GASNGINAYLC peptide led to significantly higher degree of late apoptosis compared to the SLWERLAYGIC peptide (9.3% and 4.4%, respectively). These findings were supported by increased formation of reactive oxygen species, down-regulation of survivin and Bcl-2 and up-regulated p53. CONCLUSION: This novel homing nanovehicle employing GASNGINAYLC peptide was shown to induce rapid endocytosis of ellipticine-loaded ferritins into neuroblastoma cells in selective fashion and with successful payload. Future homing peptide development via lead optimization and functional analysis can pave the way towards efficient peptide-based active delivery of nanomedicines to neuroblastoma cells.

• Keywords
• Ferritin, Homing peptide, Neuroblastoma, Norepinephrine transporter, Targeted therapy,
• MeSH
• Endocytosis genetics   MeSH
• Ferritins chemistry   MeSH
• Drug Delivery Systems methods   MeSH
• Humans MeSH
• Cell Line, Tumor MeSH
• Nanomedicine MeSH
• Nanostructures chemistry   MeSH
• Neuroblastoma metabolism   MeSH
• Peptides chemistry   genetics   metabolism   MeSH
• Norepinephrine Plasma Membrane Transport Proteins * chemistry   genetics   metabolism   MeSH
• Antineoplastic Agents chemistry   pharmacokinetics   pharmacology   MeSH
• Cell Survival drug effects   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Ferritins MeSH
• Peptides MeSH
• Norepinephrine Plasma Membrane Transport Proteins * MeSH
• Antineoplastic Agents MeSH

The electrochemical redox behavior of three trinuclear Ni(II) complexes [Ni3(abb)3(H2O)3(µ-ttc)](ClO4)3 (1), [Ni3(tebb)3(H2O)3(µ-ttc)](ClO4)3·H2O (2), and [Ni3(pmdien)3(µ-ttc)](ClO4)3 (3), where abb = 1-(1H-benzimidazol-2-yl)-N-(1H-benzimidazol-2-ylmethyl)methan-amine, ttcH3 = trithiocyanuric acid, tebb = 2-[2-[2-(1H-benzimidazol-2-yl)ethylsulfanyl]ethyl]-1H-benzimidazole, and pmdien = N,N,N',N″,N″-pentamethyldiethylenetriamine is reported. Cyclic voltammetry (CV) was applied for the study of the electrochemical behavior of these compounds. The results confirmed the presence of ttc and nickel in oxidation state +2 in the synthesized complexes. Moreover, the antibacterial properties and cytotoxic activity of complex 3 was investigated. All the complexes show antibacterial activity against Staphylococcus aureus and Escherichia coli to different extents. The cytotoxic activity of complex 3 and ttcNa3 were studied on G-361, HOS, K-562, and MCF7 cancer cell lines. It was found out that complex 3 possesses the cytotoxic activity against the tested cell lines, whereas ttcNa3 did not show any cytotoxic activity.

• Keywords
• cyclic voltammetry, nickel complexes, trimercaptotriazine, trithiocyanuric acid,
• Publication type
• Journal Article MeSH

Herein, we describe the in vivo effects of doxorubicin (DOX) encapsulated in ubiquitous protein apoferritin (APO) and its efficiency and safety in anti-tumor treatment. APODOX is both passively (through Enhanced Permeability and Retention effect) and actively targeted to tumors through prostate-specific membrane antigen (PSMA) via mouse antibodies conjugated to the surface of horse spleen APO. To achieve site-directed conjugation of the antibodies, a HWRGWVC heptapeptide linker was used. The prostate cancer-targeted and non-targeted nanocarriers were tested using subcutaneously implanted LNCaP cells in athymic mice models, and compared to free DOX. Prostate cancer-targeted APODOX retained the high potency of DOX in attenuation of tumors (with 55% decrease in tumor volume after 3 weeks of treatment). DOX and non-targeted APODOX treatment caused damage to liver, kidney and heart tissues. In contrast, no elevation in liver or kidney enzymes and negligible changes were revealed by histological assessment in prostate cancer-targeted APODOX-treated mice. Overall, we show that the APO nanocarrier provides an easy encapsulation protocol, reliable targeting, high therapeutic efficiency and very low off-target toxicity, and is thus a promising delivery system for translation into clinical use.

• MeSH
• Antigens, Surface immunology   MeSH
• Apoferritins adverse effects   therapeutic use   MeSH
• Doxorubicin adverse effects   analogs & derivatives   therapeutic use   MeSH
• Glutamate Carboxypeptidase II immunology   MeSH
• Heterografts MeSH
• Immunoconjugates therapeutic use   MeSH
• Liver drug effects   MeSH
• Kidney drug effects   MeSH
• Humans MeSH
• Mice, Inbred BALB C MeSH
• Mice, Nude MeSH
• Mice MeSH
• Cell Line, Tumor MeSH
• Prostatic Neoplasms drug therapy   therapy   MeSH
• Nanoconjugates therapeutic use   MeSH
• Heart drug effects   MeSH
• Treatment Outcome MeSH
• Xenograft Model Antitumor Assays MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Male MeSH
• Mice MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Antigens, Surface MeSH
• apoferritin doxorubicin MeSH Browser
• Apoferritins MeSH
• Doxorubicin MeSH
• FOLH1 protein, human MeSH Browser
• Glutamate Carboxypeptidase II MeSH
• Immunoconjugates MeSH
• Nanoconjugates MeSH