Cancer deaths are mainly caused by tumor metastases. However, tumor
ablation therapies can only target the primary tumor but not inhibit tumor metastasis.
Herein, a multifunctional covalent organic framework (COF)-based nanocomposite is
designed for synergetic photo-, chemodynamic- and immunotherapies. Specififically, the
synthesized COF possesses the ability to produce singlet oxygen under the 650 nm laser
irradiation. After being metallized with FeCl3, p-phenylenediamine is polymerized on
the surface of COF with Fe3+ as the oxidant. The obtained poly(p-phenylenediamine)
can be used for photothermal therapy. Meanwhile, the overexpressed H2O2 in the
tumor would be further catalyzed and decomposed into hydroxyl radicals (• OH) by the
Fe3+/Fe2+ redox couple via Fenton reaction. Intriguingly, the increase of temperature
caused by photothermal therapy can accelerate the production of • OH. Moreover, the
tumor-associated antigen induced a robust antitumor immune response and effffectively
inhibited tumor metastasis in the presence of anti-PD-L1 checkpoint blockade. Such a
COF-based multifunctional nanoplatform provides an effiffifficacious treatment strategy for
both the primary tumor and tumor metastasis.