A Near-Infrared Peptide Probe with Tumor-Specific Excretion-Retarded Effect for Image-Guided Surgery of Renal Cell Carcinoma.

Abstract

Image-guided surgery plays a crucial role in realizing complete tumor removal, reducing postoperative recurrence and increasing patient survival. However, imaging of tumor lesion in the typical metabolic organs, <i>e</i>.<i>g</i>., kidney and liver, still has great challenges due to the intrinsic nonspecific accumulation of imaging probes in those organs. Herein, we report an <i>in situ</i> self-assembled near-infrared (NIR) peptide probe with tumor-specific excretion-retarded (TER) effect in tumor lesions, enabling high-performance imaging of human renal cell carcinoma (RCC) and achieving complete tumor removal, ultimately reducing postoperative recurrence. The NIR peptide probe first specifically recognizes α_vβ₃ integrin overexpressed in renal cancer cells, then is cleaved by MMP-2/9, which is up-regulated in the tumor microenvironment. The probe residue spontaneously self-assembles into nanofibers that exhibit an excretion-retarded effect in the kidney, which contributes to a high signal-to-noise (S/N) ratio in orthotopic RCC mice. Intriguingly, the TER effect also enables precisely identifying eye-invisible tiny lesions (<1 mm), which contributes to complete tumor removal and significantly reduces the postoperative recurrence compared with traditional surgery. Finally, the TER strategy is successfully employed in high-performance identification of human RCC in an <i>ex vivo</i> kidney perfusion model. Taken together, this NIR peptide probe based on the TER strategy is a promising method for detecting tumors in metabolic organs in diverse biomedical applications.