Preliminary Application of TROP2-Targeted Peptide Screening for Real-Time Intraoperative Navigation in Pancreatic...

Fluorescence-guided surgery (FGS) in the near-infrared II (NIR-II) window offers improved tissue penetration and higher signal-to-background ratios, but widely used nonspecific probes such as indocyanine green (ICG) lack tumor selectivity, limiting their value in pancreatic ductal adenocarcinoma (PDAC). Here, we identified trophoblast cell surface antigen 2 (TROP2) as an imaging target and developed a TROP2-targeted peptide-based NIR-II probe, HCP-ICG, for precision intraoperative navigation. The high-affinity TROP2-binding peptide HCP (HYEYWDEEHEC) was discovered through an OBOC peptide library and conjugated to ICG to yield HCP-ICG. The probe exhibited nanomolar affinity (KD = 2.64 × 10^-8 M), high cellular specificity, and excellent biocompatibility. In TROP2-positive PDAC xenograft models, HCP-ICG rapidly accumulated in tumors within 0.5 h, peaked at 4 h, and maintained high tumor-to-background ratios for up to 12 h, significantly outperforming free ICG (P < 0.01). Intraoperative NIR-II imaging clearly delineated tumor margins and enabled complete fluorescence-guided resection without residual signal, while histological analyses confirmed spatial concordance with TROP2 expression and no observable toxicity in major organs. By integrating molecular targeting with NIR-II optical performance, HCP-ICG enables rapid, durable, and good imaging selectivity for TROP2-positive PDAC lesions, providing a promising strategy for precision fluorescence-guided surgery and potential extension to other TROP2-overexpressing tumors.