Peptide‐based responsive molecular fluorescent probes for precision oncology

Precision tumor theranostics are fundamentally constrained by the dynamic complexity and pronounced heterogeneity of the tumor microenvironment (TME). Conventional imaging agents and therapeutics often suffer from limited specificity, resulting in off‐target accumulation and suboptimal clinical outcomes. Peptide‐based responsive fluorescent probes have emerged as a class of adaptive functional materials that integrate tumor‐selective recognition, programmable stimulus responsiveness, and modular structural tunability. This review summarizes recent advances in peptide‐based molecular fluorescent probes for precision oncology. We first outline the key biochemical hallmarks of the TME and the design principles of responsive molecular probes, and then systematically categorize representative applications of targeting, stimulus‐responsive, and integrated peptide probes. On one hand, peptides can function as targeting ligands, stimulus‐responsive switches, and regulators of hierarchical self‐assembly. On the other hand, these probes demonstrate notable utility in high‐contrast tumor imaging, intraoperative guidance, real‐time therapeutic monitoring, and multimodal theranostic applications. Finally, emerging opportunities and challenges for next‐generation peptide‐based responsive probes are discussed, highlighting logic‐gated and cascade‐responsive designs, multimodal imaging integration, optimization of near‐infrared II fluorophores, and clinical translation. Collectively, peptide‐based responsive fluorescent probes constitute an intelligent, programmable, and highly clinically relevant platform for precision tumor theranostics.