A novel 68Ga-labeled cyclic peptide molecular probe based on the computer-aided design for noninvasive imaging of PD-L1 expression in tumors

Copyright © 2023 Elsevier Inc. All rights reserved..

Programmed death-ligand 1 (PD-L1) serves as a crucial biomarker for guiding the screening of cancer patients and the stratification of immunotherapy. However, due to the high heterogeneity of tumors, the current gold standard for detecting PD-L1 expression (immunohistochemistry) fails to comprehensively evaluate the overall PD-L1 expression levels in the body. Fortunately, the use of PD-L1 targeted radiotracers enables quantitative, real-time, and noninvasive assessment of PD-L1 expression levels and dynamics in tumors. Notably, analyzing the binding mode between the precursor and the target protein to find linker binding sites that do not affect the activity of the target molecule can greatly enhance the successful development of molecular probes. This study introduced a groundbreaking cyclic peptide molecular probe called 68Ga-DOTA-PG1. It was derived from the BMS-71 cyclic peptide and was specifically designed to evaluate the expression of PD-L1 in tumors. The radiolabeling yield of 68Ga-DOTA-PG1 surpassed 97% while maintaining a radiochemical purity of over 99%. In vitro experiments demonstrated the effective targeting of PD-L1 in tumor cells by 68Ga-DOTA-PG1, with significantly higher cellular uptake observed in A375-hPD-L1 cells (PD-L1 + ) compared to A375 cells (PD-L1-). Biodistribution and PET imaging studies consistently showed specific accumulation of 68Ga-DOTA-PG1 in A375-hPD-L1 tumors, with a maximum uptake of 11.06 ± 1.70% ID/g at 2 h, significantly higher than the tumor uptake in A375 cells (1.70 ± 0.17% ID/g). These results strongly indicated that 68Ga-DOTA-PG1 held great promise as a PET radiotracer for imaging PD-L1-positive tumors.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:140

Enthalten in:

Bioorganic chemistry - 140(2023) vom: 02. Nov., Seite 106785

Sprache:

Englisch

Beteiligte Personen:

Ge, Shushan [VerfasserIn]
Zhang, Bin [VerfasserIn]
Li, Jihui [VerfasserIn]
Shi, Jinyu [VerfasserIn]
Jia, Tongtong [VerfasserIn]
Wang, Yan [VerfasserIn]
Chen, Zhengguo [VerfasserIn]
Sang, Shibiao [VerfasserIn]
Deng, Shengming [VerfasserIn]

Links:

Volltext

Themen:

B7-H1 Antigen
CD274 protein, human
Gallium Radioisotopes
Immune checkpoint
Journal Article
Macrocyclic peptide radiotracer
Micro PET/CT
Molecular Probes
Molecular docking
Peptides, Cyclic
Programmed death ligand 1
Research Support, Non-U.S. Gov't
Tumor imaging

Anmerkungen:

Date Completed 18.09.2023

Date Revised 18.09.2023

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.bioorg.2023.106785

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM361378572