Abstract
The urokinase-type plasminogen activator receptor (uPAR, CD87) connects extracellular proteolysis with adhesion, migration, and signaling, providing a biological rationale for imaging tumor-associated invasion. This narrative review examines receptor biology, radiopharmaceutical development, clinical PET evidence, targeted MRI, fluorescence-guided surgery, and therapeutic translation. Experimental studies and early clinical investigations support the technical feasibility of visualizing uPAR with peptide-based probes, particularly AE105 derivatives labeled with copper-64 or gallium-68. Prospective cohorts have reported associations between uptake and prostate cancer grade, glioma outcomes, and relapse risk in head and neck cancer. These findings remain specific to the patient population, tracer, measurement, and endpoint; they do not establish universal SUVmax thresholds. Receptor expression in stromal and inflammatory cells also limits interpretation of uptake as an exclusively malignant-cell signal. The review distinguishes uPAR PET from FDG imaging, circulating soluble uPAR assays, and tissue immunohistochemistry. Clinical findings are considered alongside their limitations, including small cohorts, optimized cutoffs, wide confidence intervals, and incomplete external validation. Optical imaging with FG001 has demonstrated the visualization of tumors in human patients, whereas the effect of fluorescence-guided decisions on surgical margins and outcomes requires further evaluation. Albumin-binding radiopeptides, cyclic ligands, and targeted nanoparticles remain important translational approaches. Sponsor-reported early therapeutic observations are identified separately from peer-reviewed efficacy evidence. Overall, uPAR-directed imaging is a promising addition to molecular oncology, but its clinical value depends on standardized measurements and prospective studies demonstrating benefit for defined diagnostic, prognostic, or treatment decisions.
Keywords: uPAR; Molecular Imaging; PET/CT; AE105; Tumor Invasion; Prognosis; Fluorescence-Guided Surgery; Theranostics
Abstract
The urokinase-type plasminogen activator receptor (uPAR, CD87) connects extracellular proteolysis with adhesion, migration, and signaling, providing a biological rationale for imaging tumor-associated invasion. This narrative review examines receptor biology, radiopharmaceutical development, clinical PET evidence, targeted MRI, fluorescence-guided surgery, and therapeutic translation. Experimental studies and early clinical investigations support the technical feasibility of visualizing uPAR with peptide-based probes, particularly AE105 derivatives labeled with copper-64 or gallium-68. Prospective cohorts have reported associations between uptake and prostate cancer grade, glioma outcomes, and relapse risk in head and neck cancer. These findings remain specific to the patient population, tracer, measurement, and endpoint; they do not establish universal SUVmax thresholds. Receptor expression in stromal and inflammatory cells also limits interpretation of uptake as an exclusively malignant-cell signal. The review distinguishes uPAR PET from FDG imaging, circulating soluble uPAR assays, and tissue immunohistochemistry. Clinical findings are considered alongside their limitations, including small cohorts, optimized cutoffs, wide confidence intervals, and incomplete external validation. Optical imaging with FG001 has demonstrated the visualization of tumors in human patients, whereas the effect of fluorescence-guided decisions on surgical margins and outcomes requires further evaluation. Albumin-binding radiopeptides, cyclic ligands, and targeted nanoparticles remain important translational approaches. Sponsor-reported early therapeutic observations are identified separately from peer-reviewed efficacy evidence. Overall, uPAR-directed imaging is a promising addition to molecular oncology, but its clinical value depends on standardized measurements and prospective studies demonstrating benefit for defined diagnostic, prognostic, or treatment decisions.
Keywords: uPAR; Molecular Imaging; PET/CT; AE105; Tumor Invasion; Prognosis; Fluorescence-Guided Surgery; Theranostics
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How to cite:
Imrana Tanvir, Hammad Nasir, Tuba Binte Qasim, Samah Said Elbasateeny, Sawsan Sabiq, Nasir Saleem, Fehmida Bibi, Muhammad Imran Naseer. uPAR-Targeted Imaging of Tumor Invasion, Prognosis, and Theranostics: A Narrative Review. Revista Cultura Científica, 2026 Issue 24. pg. 2491-2505.
Publication History
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Received: 19/08/2026
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Accepted: 29/10/2026
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Published: 07/11/2026
Copyright © 2026, Imrana Tanvir, Hammad Nasir, Tuba Binte Qasim, Samah Said Elbasateeny, Sawsan Sabiq, Nasir Saleem, Fehmida Bibi, Muhammad Imran Naseer. Published by Revista Cultura Científica. This article is published as open access under the Creative Commons Attribution 4.0 International (CC BY 4.0) license (
http://creativecommons.org/licenses/by/4.0/).