A narrative review: progress in transition metal-mediated bioorthogonal catalysis for the treatment of solid tumors

Background and Objective: Transition metals are commonly used catalysts in bioorthogonal chemistry and have attracted extensive attention in biochemistry because of their efficient catalytic performance. In recent years, transition metal-mediated cycloaddition reactions, bond cleavage, and formation reactions are being actively explored for tumor treatment. However, the direct application of transition metals in complex biological environments has several problems, including poor solubility, toxicity, and easy inactivation. The combination of transition metals and nanomaterials can solve those problems by playing a bioorthogonal catalytic role in tumor treatment. In this review, we summarize some research on the application of transition metals modified by nanomaterials in tumor therapy and discuss the potential and challenges of transition metal-mediated bioorthogonal therapy in comprehensive tumor therapy. Methods: English literature on transition metal in cancer treatment was searched in PubMed and Web of Science. The main search terms were "cancer treatment", "bioorthogonal reaction", "transition metal", "bioorthogonal catalysis", etc. Key Content and Findings: This review summarizes research on several major transition metals that can be used for bioorthogonal catalysis with the assistance of nanomaterials in anti-tumor therapy. In addition, bioorthogonal catalysis is a new supplement to antitumor therapy. We have compiled the potential challenges of the clinical application of transition metal-based nanocatalysts, which lays the foundation for future research related to medicinal chemistry and targeted cancer therapy. Conclusions: Most of the transition metals still have a lot of room for exploration in cancer treatment research. We still need more research to confirm the feasibility of in vivo and clinical trials.