Recent progress in covalent organic frameworks for cancer therapy.

Covalent organic frameworks (COFs) have gained tremendous interest in cancer therapy owing to their multifunctional properties, such as biocompatibility, tunable cavities, excellent crystallinity, ease of modification/functionalization, and high flexibility. These unique properties offer multiple benefits, such as high loading capacity, prevention from premature leakage, targeted delivery to the tumor microenvironment (TME), and release of therapeutic agents in a controlled manner, which makes them effective and excellent nanoplatforms for cancer therapeutics. In this review, we outline recent advances in using COFs as delivery system for chemotherapeutic agents, photodynamic therapy (PDT), photothermal therapy (PTT), sonodynamic therapy (SDT), cancer diagnostics, and combinatorial therapy for cancer therapeutics. We also summarize current challenges and future directions of this unique research field.