Photodynamic therapy (PDT) as a noninvasive therapy mode has attracted considerable attention in the field of oncotherapy. However, the PDT efficacy is restricted either by the tumor hypoxia environment or the inherent properties of photosensitizers (PSs) including bad water solution, photobleaching, and easy aggregation. Herein, we designed and synthesized a new two-dimensional (2D) metal−organic framework, Sm-tetrakis(4-carboxyphenyl)porphyrin (TCPP) nanosheets, by assembling transition metal ions (Sm 3+ ) and PSs (TCPP), on which the catalase (CAT)-mimicking platinum nanozymes were then in situ grown for sufficient oxygen supply during PDT. The prepared Sm-TCPP with nanoplate morphology (∼100 nm in diameter) and ultrathin thickness (<10 nm) showed significantly enhanced 1 O 2 generation capacity due to the improved physicochemical properties and the enhanced intersystem crossing from heavy Sm nodes. More importantly, the CAT-mimicking Pt nanozyme on the Sm-TCPP nanosheets could effectively convert over-expressed H 2 O 2 in the tumor microenvironment into O 2 to relieve tumor hypoxia. Further, the triphenylphosphine (TPP) molecule was introduced to Sm-TCPP-Pt to develop a mitochondrion-targeting and O 2 self-supply PDT system. The in vitro and in vivo experimental results based on the MCF-7 breast cancer model revealed that Sm-TCPP-Pt/TPP could relieve tumor hypoxia and the generated reactive oxygen species nearby intracellular mitochondria significantly induced cell apoptosis. This study offers an engineering strategy to integrate 2D PS-based metal−organic frameworks and nanozymes into a nanoplatform to surmount the pitfalls of traditional PDT.

Herein, a biocompatible 2D metal-organic frameworks (Cu-TCPP(Fe)) based on TCPP(M) (TCPP = tetrakis (4-carboxyphenyl) porphyrin, M = Fe) and copper ion were synthesized as a novel drug carrier. Sequentially, the cisplatin was loaded on the merge of carboxyl-rich Cu-TCPP(Fe) through forming favorable carboxyl-drug interactions. The prepared Pt/Cu-TCPP(Fe) showed highly enhanced cytotoxicity than that of free cisplatin in human pulmonary carcinoma A549 cells, whereas inverse inhibitory effects were observed in human normal BEAS-2B cells. Further, the mechanism of action about the desirable results was also elaborated. Our study highlighted the potential synergies between the nanocarrier and the anticancer drugs.

Until now, ferroptotic therapeutic strategies remain simple, although ferroptosis has aroused extensive interest owing to its escape from the biocarriers of conventional therapeutic modalities. Herein, we construct a photothermal (PT)- and autophagy-enhanced ferroptotic therapeutic modality based on MnO2@HMCu2–x S nanocomposites (HMCMs) for efficient tumor ablation. The HMCMs possess PT-enhanced glutathione (GSH) depletion capability, thereby inducing PT-enhanced ferroptosis via the reinforced inactivation of glutathione peroxidase 4 (GPX4). Thereafter, the GSH-responsed Mn2+ release could generate reactive oxygen species (ROS) by a Fenton-like reaction to reinforce the intracellular oxidative stress for the lipid hydroperoxide (LPO) accumulation in ferroptosis. Additionally, an autophagy promotor rapamycin (Rapa) was loaded into HMCM for sensitizing cells to ferroptosis due to the indispensable role of autophagy in the ferroptosis process. The in vitro and in vivo data demonstrated that the HMCM exhibited superior anticancer effect in human breast cancer models and that the combined therapeutic system afforded the next generation of ferroptotic therapy for combatting malignant tumors.

Highly toxic reactive oxygen species levels were enhanced via iron oxide core–shell mesoporous silica nanocarrier-mediated Fenton reactions for cancer therapy.

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