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We reported the synthesis of a tris(triazolylmethyl)amine (TTA)-bridged organosilane, functioning as Cu(I)-stabilizing ligands, and the installation of this building block into the backbone of mesoporous organosilica nanoparticles (TTASi) by a sol–gel way. Upon coordinating with Cu(I), the mesoporous CuI-TTASi, with a restricted metal active center inside the pore, functions as a molecular-sieve-typed nanoreactor to efficiently perform Cu(I)-catalyzed alkyne–azide cycloaddition (CuAAC) reactions on small-molecule substrates but fails to work on macromolecules larger than the pore diameter. As a proof of concept, we witnessed the advantages of selective nanoreactors in screening protein substrates for small molecules. Also, the robust CuI-TTASi could be implanted into the body of animal models including zebrafish and mice as biorthogonal catalysts without apparent toxicity, extending its utilization in vivoranging from fluorescent labeling to in situdrug synthesis.

Cutting off the energy supply by glucose oxidase (GOx) to starve cancer cells has been a feasible and efficient oncotherapy strategy. The employment of GOx can effectively starve tumor cells by aerobic hydrolysis of glucose hopefully strengthening the abnormality (including the decrease in pH, the increase of hypoxia, and toxic hydrogen peroxide) in the tumor microenvironment (TME). On this basis, we designed and fabricated a GOx-conjugated yolk–shell Ag@mSiO2nanoframe with Ag NPs and GOx-conjugated mesoporous silica as the yolk and the shell, respectively, to make full use of changes the GOx induces in TME. Specifically, lower pH and H2O2could accelerate the transformation of Ag nanoparticles to poisonous Ag ions. At the same time, the anabatic hypoxia condition in turn activated chemotherapy drug tirapazamine (TPZ) to exert a chemotherapeutic effect, thereby achieving effective chemo/starvation and metal ion multimodality therapy. The drug release experiment in vitro demonstrated that the GOx is the key to the nanocarriers, which can activate the whole system. The excellent cellular uptake performances of nanocarriers were corroborated by a confocal laser scanning microscope (CLSM). In addition, its superb cancer-killing effect has been confirmed by cytotoxicity and apoptosis experiments. These results indicated that the drug-delivery system achieved the cascade cancer-killing process in situ and synergistic chemo/starvation/metal ion therapy, which has a bright prospect for treating cancer.

Surmounting the restriction issues of nitric oxide (NO) delivery to realize their precious on-demand release is highly beneficial for the widespread deployment of gas therapy for application in biomedicine. Herein, by employing core–shell structure Au@SiO2nanomaterials with high photothermal performance, a novel strategy was proposed by integrating photothermal conversion nanomaterials and heat-triggered NO donors (RSNO) into a nanoplatform, which achieved photothermal therapy (PTT)-enhanced NO gas therapy under near-infrared (NIR) radiation. Specifically, 2-phenylethynesulfonamide (PES), an inhibitor of heat shock protein 70 (HSP-70), was loaded into the NO nanogenerators to realize effective low-temperature (∼45 °C) PTT. The obtained results showed that the near-infrared radiation (NIR) mediated mild PTT and gas therapy by releasing NO showed a substantially improved synergistic effect based on in vitro and in vivo results in breast cancer (MCF-7) models. Our study points out a strategy to realize mild photothermal therapy by inhibiting the expression of HSP-70 and simultaneously providing an avenue to achieve controllable release of NO. More important, this research highlights the great potential of multifunctional therapeutic agents in the synergistic treatment of cancer.

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 (Sm3+) 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 1O2generation 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 H2O2in the tumor microenvironment into O2to relieve tumor hypoxia. Further, the triphenylphosphine (TPP) molecule was introduced to Sm-TCPP-Pt to develop a mitochondrion-targeting and O2self-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.

Employing transition metal catalysts (TMCs) to perform bioorthogonal activation of prodrugs and pro-fluorophores in biological systems, particularly in a conditional fashion, remains a challenge. Here, we used a mesoporous organosilica nanoscaffold (RuMSN), which localizes Ru(II) conjugates on the pore wall, enabling the biorthogonal photoreduction reactions of azide groups. Due to easily adjustable surface charges and pore diameter, this efficiently engineering RuMSN catalyst, with abundant active sites on the inner pore well, could spontaneously repel or attract substrates with different molecular sizes and charges and thus ensure selective bioorthogonal catalysis. Depending on it, engineering RuMSN nanoreactors showed fascinating application scales from conditional bioorthogonal activation of prodrugs and pro-fluorophores in either intra- or extracellular localization to performing intracellular concurrent and tandem catalysis together with natural enzymes.

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–xS 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.

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.

Though the exciting advancements in liposome formulations composed of phosphorylcholine (PC) lipid bilayers for antitumor therapy, their clinical efficacy is hindered by the challenge of triggering cargo release. Zwitterionic choline phosphate (CP) liposomes, with reversed charge orientation, possessed improved bioorthogonality and drug accumulations than that of phosphorylcholine. Here, we report the synthesis of five CP-typed lipids with different carbon chain lengths and ROS-responsive thioether moieties. These lipids self-assemble into CP liposomes capable of efficiently encapsulating doxorubicin (DOX) at a high drug loading capacity (approximately 7.6 wt % for DOX/12S-CPs). Compared to PC liposomes, our findings demonstrate that CP liposomes exhibit excellent stability under physiological conditions while rapidly triggering DOX release in a simulated high oxidation tumor environment. Furthermore, the experimental results in vitro and in vivo reveal the preferential localization of CP liposomes at the tumor site and their enhanced internalization by tumor cells compared to PC liposomes. Consequently, DOX/S-CPs exhibit superior tumor inhibition effects when compared to free DOX or DOX/HSPCs. In summary, our study highlights the potential of thioether-modified CP liposomes as highly efficient formulations for controlled drug release in cancer therapy.