Near-Infrared Organic Room Temperature Phosphorescent Probes Targeting Fibroblast Activation Protein for Surgical Navigation of Liver Cancer

Abstract

Hepatectomy is a critical treatment for liver cancer, but achieving complete tumor removal remains challenging. The development of tumor-targeting probes capable of accurately identifying tumor locations and providing real-time intraoperative navigation is of significant clinical importance. We synthesize a tumor-targeted probe by conjugating a fibroblast activation protein inhibitor (FAPI) with near-infrared organic room temperature phosphorescence (RTP) material. We then analyze its surgical navigation performance in the liver cancer model and its imaging performance in fresh patient-derived samples. In vivo validation reveals that the probe exhibits optimal phosphorescence intensity within 48 h (8.53 × 10⁵ p s⁻¹ cm⁻² sr⁻¹) and an average signal-to-noise ratio of 16. The probe could effectively identify FAP-positive samples from liver cancer patients. The successful application of phosphorescence-guided surgery suggests that the near-infrared RTP probe holds significant clinical translational value and could serve as an auxiliary tool for the surgical treatment of liver cancer.

Keywords

fibroblast activation protein / liver cancer / near-infrared organic room temperature phosphorescence / surgical navigation

References

[1] F. Bray, M. Laversanne, H. Sung, et al., “Global Cancer Statistics 2022: GLOBOCAN Estimates of Incidence and Mortality Worldwide for 36 Cancers in 185 Countries,” CA: A Cancer Journal for Clinicians 74 (2024): 229-263.

[2] J. M. Llovet, R. Pinyol, M. Yarchoan, et al., “Adjuvant and Neoadjuvant Immunotherapies in Hepatocellular Carcinoma,” Nature Reviews Clinical Oncology 21 (2024): 294-311.

[3] L. Alaimo, Z. Moazzam, Y. Endo, et al., “The Application of Artificial Intelligence to Investigate Long-Term Outcomes and Assess Optimal Margin Width in Hepatectomy for Intrahepatic Cholangiocarcinoma,” Annals of Surgery 279 (2024): 471-478.

[4] S. Chen, D. Zhuang, Q. Jia, B. Guo, and G. Hu, “Advances in Noninvasive Molecular Imaging Probes for Liver Fibrosis Diagnosis,” Biomaterials Research 28 (2024): 0042.

[5] W. Zhang, J. Liu, P. Li, X. Wang, and B. Tang, “Reversible Fluorescent Probes for Dynamic Imaging of Liver Ischemia-Reperfusion Injury,” Accounts of Chemical Research 57 (2024): 2594-2605.

[6] T. Aoki, D. Yasuda, Y. Shimizu, et al., “Image-Guided Liver Mapping Using Fluorescence Navigation System With Indocyanine Green for Anatomical Hepatic Resection,” World Journal of Surgery 32 (2008): 1763-1767.

[7] F. B. Achterberg, O. D. Bijlstra, M. D. Slooter, G. Dutch Liver Surgery, et al., “ICG-Fluorescence Imaging for Margin Assessment During Minimally Invasive Colorectal Liver Metastasis Resection,” JAMA Network Open 7 (2024): e246548.

[8] a) Z. Hu, C. Fang, B. Li, et al., “First-In-Human Liver-Tumour Surgery Guided by Multispectral Fluorescence Imaging in the Visible and Near-Infrared-I/II Windows,” Nature Biomedical Engineering 4 (2020): 259-271. b) B. Wang, C. Tang, E. Lin, et al., “NIR-II Fluorescence-Guided Liver Cancer Surgery by a Small Molecular HDAC6 Targeting Probe,” EBioMedicine 98 (2023): 104880. c) Q. Qiu, T. Chang, Y. Wu, C. Qu, H. Chen, and Z. Cheng, “Liver Injury Long-Term Monitoring and Fluorescent Image-Guided Tumor Surgery Using Self-Assembly Amphiphilic Donor-Acceptor NIR-II Dyes,” Biosensors & Bioelectronics 212 (2022): 114371. d) L. J. Lauwerends, P. van Driel, R. J. Baatenburg de Jong, et al., “Real-Time Fluorescence Imaging in Intraoperative Decision Making for Cancer Surgery,” The Lancet Oncology 22 (2021): e186-e195. e) Q. Zong, J. Li, Q. Xu, Y. Liu, K. Wang, and Y. Yuan, “Self-Immolative Poly(thiocarbamate) With Localized H2S Signal Amplification for Precise Cancer Imaging and Therapy,” Nature Communications 15 (2024): 7558.

[9] B. Chang, D. Li, Y. Ren, et al., “A Phosphorescent Probe for In Vivo Imaging in the Second Near-Infrared Window,” Nature Biomedical Engineering 6 (2022): 629-639.

[10] a) H. Zheng, Z. Zhang, S. Cai, Z. An, and W. Huang, “Enhancing Purely Organic Room Temperature Phosphorescence via Supramolecular Self-Assembly,” Advanced Materials 36 (2024): e2311922. b) X. Li, Y. Wang, Z. Zhang, S. Cai, Z. An, and W. Huang, “Recent Advances in Room-Temperature Phosphorescence Metal–Organic Hybrids: Structures, Properties, and Applications,” Advanced Materials 36 (2024): e2308290. c) Y. Zhang, J. Li, J. Zhao, et al., “π–π Interaction-Induced Organic Long-wavelength Room-Temperature Phosphorescence for In Vivo Atherosclerotic Plaque Imaging,” Angewandte Chemie International Edition 63 (2024): e202313890. d) S. Li, J. Gu, J. Wang, et al., “Excellent Persistent Near-Infrared Room Temperature Phosphorescence From Highly Efficient Host–Guest Systems,” Advanced Science 11 (2024): e2402846.

[11] a) Y. Li, Z. Wu, Z. Huang, C. Yin, H. Tian, and X. Ma, “Activatable red/near-infrared aqueous organic phosphorescence probes for improved time-resolved bioimaging,” National Science Review 12 (2025): nwae383. b) X. He, W. Huang, Y. Zheng, et al., “Achieving Room-Temperature Phosphorescence in Solution Phase from Carbon Dots Confined in Nanocrystals,” Angewandte Chemie International Edition (2025): e202423388.

[12] a) Y. Fan, S. Liu, M. Wu, et al., “Mobile Phone Flashlight-Excited Red Afterglow Bioimaging,” Advanced Materials 34 (2022): e2201280. b) J. Gu, W. Yuan, K. Chang, et al., “Organic Materials With Ultrabright Phosphorescence at Room Temperature Under Physiological Conditions for Bioimaging,” Angewandte Chemie International Edition 64 (2025): e202415637.

[13] a) Y. Xiao and D. Yu, “Tumor microenvironment as a therapeutic target in cancer,” Pharmacology & Therapeutics 221 (2021): 107753. b) A. Varveri, M. Papadopoulou, Z. Papadovasilakis, et al., Nature Communications 15 (2024): 4988.

[14] L. Zhao, J. Chen, Y. Pang, et al., “Fibroblast activation protein-based theranostics in cancer research: A state-of-the-art review,” Theranostics 12 (2022): 1557-1569.

[15] D. Peng, J. Cao, C. Guo, et al., “Influence of Cirrhosis on 68 Ga-FAPI PET/CT in Intrahepatic Tumors,” Radiology 307 (2023): e222448.

[16] X. Yang, C. Yang, S. Zhang, et al., “Precision treatment in advanced hepatocellular carcinoma,” Cancer Cell 42 (2024): 180-197.

[17] H. Chen, H. Cheng, Q. Dai, et al., “A superstable homogeneous lipiodol-ICG formulation for locoregional hepatocellular carcinoma treatment,” Journal of Controlled Release 323 (2020): 635-643.

[18] J. Li, F. Zhu, K. Lou, et al., “Tumor microenvironment enhanced NIR II fluorescence imaging for tumor precise surgery navigation via tetrasulfide mesoporous silica-coated Nd-based rare-earth nanocrystals,” Materials Today Bio 16 (2022): 100397.

[19] R. Q. Yang, P. Y. Wang, K. L. Lou, et al., “Biodegradable Nanoprobe for NIR-II Fluorescence Image-Guided Surgery and Enhanced Breast Cancer Radiotherapy Efficacy,” Advanced Science 9 (2022): e2104728.

[20] W. Dai, Y. Jiang, Y. Lei, et al., “Recent progress in ion-regulated organic room-temperature phosphorescence,” Chemical Science 15 (2024): 4222-4237.

[21] a) D. H. Kang, Y. Zeng, M. Tewari, and J. Kim, “Highly sensitive and quantitative biodetection With lipid-polymer hybrid nanoparticles having organic room-temperature phosphorescence,” Biosensors & Bioelectronics 199 (2022): 113889. b) Y. Zhao, J. Yang, C. Liang, et al., “Fused-Ring Pyrrole-Based Near-Infrared Emissive Organic RTP Material for Persistent Afterglow Bioimaging,” Angewandte Chemie International Edition 63 (2024): e202317431.

[22] a) M. Bocci, A. Zana, L. Principi, et al., “In vivo activation of FAP-cleavable small molecule-drug conjugates for the targeted delivery of camptothecins and tubulin poisons to the tumor microenvironment,” Journal of Controlled Release 367 (2024): 779-790. b) M. Bocci, L. Principi, E. Gilardoni, D. Neri, S. Cazzamalli, and A. Galbiati, “Delivery of Monomethyl Auristatin F to the Tumor Microenvironment With Noninternalizing Fibroblast Activation Protein-Cleavable Small Molecule–Drug Conjugates Elicits Potent In Vivo Anticancer Activity,” Bioconjugate Chemistry 36 (2025): 15-19. c) Y. Mori, K. Dendl, J. Cardinale, et al., “FAPI PET: Fibroblast Activation Protein Inhibitor Use in Oncologic and Nononcologic Disease,” Radiology 306 (2023): e220749.

[23] L. Jinghua, X. Kui, G. Deliang, et al., “Clinical prospective study of Gallium 68 (68Ga)-labeled fibroblast-activation protein inhibitor PET/CT in the diagnosis of biliary tract carcinoma,” European Journal of Nuclear Medicine and Molecular Imaging 50 (2023): 2152-2166.

[24] J. Millul, G. Bassi, J. Mock, et al., “An ultra-high-affinity small organic ligand of fibroblast activation protein for tumor-targeting applications,” Proceedings of the National Academy of Sciences of the United States of America 118 (2021): e2101852118.

RIGHTS & PERMISSIONS

2025 The Author(s). Aggregate published by SCUT, AIEI, and John Wiley & Sons Australia, Ltd.