Copper-Based Metal-Organic Framework Enables ROS Amplification and Drug Potency Activation.

Reactive oxygen species (ROS)-induced cancer therapy is extremely limited by tumor hypoxia, insufficient endogenous hydrogen peroxide (H2O2), overexpressed glutathione (GSH), and slower reaction rate. To address these challenges, in this paper, a hybrid nanomedicine (CaO2@Cu/ZIF-8-ICG@LA, CCZIL) is developed using a copper-based metal-organic framework (Cu/ZIF-8) for cancer synergistic therapy. H2O2/O2 self-supplementing, GSH-depleting, and photothermal properties multiply amplify ROS generation. Moreover, disulfiram (DSF) chemotherapy (CT) was activated by chelating with Cu2+ to synergize therapy. This novel strategy has enormous potential for ROS-involved synergistic antitumor therapy.

pH-responsive nanocatalyst for enhancing cancer therapy via H2O2 homeostasis disruption and disulfiram sensitization.

Due to the powerful redox homeostasis and inefficiency of monotherapy, chemodynamic therapy (CDT) is clinically limited. Despite great efforts, the design of CDT nanosystems with specific H2O2 homeostasis and effective integration of multiple treatments remains a great challenge. Therefore, herein, we engineer a novel pH-responsive nanocatalyst to disrupt intracellular H2O2 homeostasis through consuming glutathione (GSH), elevating H2O2 and restraining H2O2 elimination, as well as achieving a combination of CDT and chemotherapy (CT) through sensitized DSF. In the formulation, amplified CDT synergized enhanced CT significantly, strengthening the tumor therapeutic efficacy in vitro and in vivo. This work not only solves intracellular redox homeostasis disruption, but also realizes the re-use of old drugs, providing new insights for CDT-based multimodal cancer therapy.

Enzyme functionalized PEOz modified magnetic polydopamine with enhanced penetration for cascade-augmented synergistic tumor therapy.

In recent years, reactive oxygen species (ROS)-mediated cancer therapies have been widely recognized for their high selectivity and good biological safety. However, due to the difficulties of endogenous tumor microenvironment (TME), penetration of tumor tissues and integration of multimodal tumor ablation, the treatment with traditional therapies could not achieve satisfactory tumor inhibition effects. Here, a doxorubicin (DOX)-glucose oxidase (GOx) dual-loaded and poly (2-ethyl-2-oxazoline) (PEOz) decorated magnetic polydopamine nanoparticles (Fe3O4-DOX@PDA-GOx@PEOz, FDPGP) were constructed for tumor ablation. GOx-mediated cascade enzyme reactions could amplify oxidative stress damage and further synergistically inhibit breast cancer. Its pH-responsive charge reversal, drug-controlled release, photothermal, and cascade reactions were evaluated through extracellular experiments. Cellular uptake, cell cytotoxicity, tumor penetration and therapeutic efficacy of FDPGP were investigated through intracellular experiments. Finally, in vivo distribution, photothermal, synergistic antitumor therapeutic effect and biosafety were evaluated comprehensively by in vivo experiments. Excitingly, outstanding tumor enrichment and penetration, superior anticancer effects and biosafety were achieved by the combination of photothermal therapy (PTT)/starvation therapy (ST)/chemodynamic therapy (CDT)/chemotherapy (CT). As such, the FDPGP nanoplatform provides a new insight into the development of collaboratively multimodal enhanced tumor therapy.

Tumor microenvironment (TME)-modulating nanoreactor for multiply enhanced chemodynamic therapy synergized with chemotherapy, starvation, and photothermal therapy.

The combination of chemotherapy (CT) and chemodynamic therapy (CDT) via nanoscale drug delivery systems has great potential for tumor therapy. Nevertheless, the low intracellular H2O2 and high reductive glutathione (GSH) levels, as well as the mildly acidic conditions (pH 5.8-6.8) of the tumor microenvironment (TME) still limit their further applications. To tackle these problems, a TME-modulating nanoreactor (denoted as Fe3O4-DOX@PDA-GOx@HA, FDPGH) was developed through a simple and practicable method to achieve multiply enhanced CDT synergized with CT, starvation therapy (ST), and photothermal therapy (PTT). Upon cellular uptake, the hyaluronic acid (HA) and PDA shells rapidly collapsed to release Fe3O4, glucose oxidase (GOx) and doxorubicin (DOX), and the overexpressed GSH could promote the reduction of Fe3+ to Fe2+, resulting in CDT activation. GOx-driven oxidation reaction not only produced H2O2 for enhanced CDT, but also killed tumor cells by initiating ST. In addition, the acid amplification caused by gluconic acid production in turn accelerated the degradation of FDPGH, promoting the Fenton reaction to enhance CDT. Most importantly, the nanoreactor had excellent photothermal performance to achieve PTT and PTT-enhanced CDT with the release of DOX into tumor tissue to achieve enhanced CT. This novel cascade nanoreactor with TME-modulating capability is intended to provide further inspiration for multimodal treatment paradigms.

NIR-Activated Thermosensitive Liposome-Gold Nanorod Hybrids for Enhanced Drug Delivery and Stimulus Sensitivity.

Combinatorial photothermal therapy and chemotherapy is an extremely promising tumor therapeutic modality. However, such systems still remain challenges in stimulus sensitivity, avoiding drug leakage, and therapeutic safety. To solve these problems, we engineered actively loaded doxorubicin (DOX) and gold nanorod (GNR) liposomes through embedding stiff hollow mesoporous silica nanoparticles (HMSNs) in the liposomal water cavity (HMLGDB) to resist the influence of shear force of GNRs to prevent drug leakage. Under 808 nm laser irradiation, the ambient temperature was raised greatly because of the photothermal conversion of GNRs, thereby rupturing the lipid layer and then triggering the DOX release. The results of in vitro experiments showed that the low concentration of HMLGDB (15 µg/mL) could effectively overcome the MCF-7 cells (human breast cancer cell line) by the increase of DOX concentration intracellularly and the good photothermal effect of GNRs. After intravenous injection, HMLGDB exhibited intratumor aggregation and PTT capacity. Furthermore, the combined chemo-photothermal antitumor strategy demonstrated a high inhibition of tumor growth and low damage to normal tissues. The developed hybrids provide a paradigm for efficient combinatorial photothermal therapy (PTT) and chemotherapy (CT).