Phase and Defect Engineering of MoSe2 Nanosheets for Enhanced NIR-II Photothermal Immunotherapy.

Inducing immunogenic cell death (ICD) during photothermal therapy (PTT) has the potential to effectively trigger photothermal immunotherapy (PTI). However, ICD induced by PTT alone is often limited by inefficient PTT, low immunogenicity of tumor cells, and a dysregulated redox microenvironment. Herein, we develop MoSe2 nanosheets with high-percentage metallic 1T phase and rich exposed active Mo centers through phase and defect engineering of MoSe2 as an effective nanoagent for PTI. The metallic 1T phase in MoSe2 nanosheets endows them with strong PTT performance, and the abundant exposed active Mo centers endow them with high activity for glutathione (GSH) depletion. The MoSe2-mediated high-performance PTT synergizing with efficient GSH depletion facilitates the release of tumor-associated antigens to induce robust ICD, thus significantly enhancing checkpoint blockade immunotherapy and activating systemic immune response in mouse models of colorectal cancer and triple-negative metastatic breast cancer.

Nanoparticles for inducing Gaucher disease-like damage in cancer cells.

Nutrient avidity is one of the most distinctive features of tumours. However, nutrient deprivation has yielded limited clinical benefits. In Gaucher disease, an inherited metabolic disorder, cells produce cholesteryl-glucoside which accumulates in lysosomes and causes cell damage. Here we develop a nanoparticle (AbCholB) to emulate natural-lipoprotein-carried cholesterol and initiate Gaucher disease-like damage in cancer cells. AbCholB is composed of a phenylboronic-acid-modified cholesterol (CholB) and albumin. Cancer cells uptake the nanoparticles into lysosomes, where CholB reacts with glucose and generates a cholesteryl-glucoside-like structure that resists degradation and aggregates into microscale crystals, causing Gaucher disease-like damage in a glucose-dependent manner. In addition, the nutrient-sensing function of mTOR is suppressed. It is observed that normal cells escape severe damage due to their inferior ability to compete for nutrients compared with cancer cells. This work provides a bioinspired strategy to selectively impede the metabolic action of cancer cells by taking advantage of their nutrient avidity.

Chiral coordination polymer nanowires boost radiation-induced in situ tumor vaccination.

Radiation-induced in situ tumor vaccination alone is very weak and insufficient to elicit robust antitumor immune responses. In this work, we address this issue by developing chiral vidarabine monophosphate-gadolinium nanowires (aAGd-NWs) through coordination-driven self-assembly. We elucidate the mechanism of aAGd-NW assembly and characterize their distinct features, which include a negative surface charge, ultrafine topography, and right-handed chirality. Additionally, aAGd-NWs not only enhance X-ray deposition but also inhibit DNA repair, thereby enhancing radiation-induced in situ vaccination. Consequently, the in situ vaccination induced by aAGd-NWs sensitizes radiation enhances CD8+ T-cell-dependent antitumor immunity and synergistically potentiates the efficacy immune checkpoint blockade therapies against both primary and metastatic tumors. The well-established aAGd-NWs exhibit exceptional therapeutic capacity and biocompatibility, offering a promising avenue for the development of radioimmunotherapy approaches.

Iron-based nanoscale coordination polymers synergistically induce immunogenic ferroptosis by blocking dihydrofolate reductase for cancer immunotherapy.

Iron is indispensable for cancer cell survival and cancer cells are more vulnerable to ferroptosis than normal cells. Ferroptosis holds promise for overcoming chemoresistance and inducing tumor immunogenic cell death, which offers new possibilities for cancer immunotherapy. However, the prevalence of immunogenic ferroptosis in cancer cells is diminished because of the high levels of reducing substances within tumor microenvironments. Ferroptosis-needed iron is overdose for livings, which is also an obstacle for effective immune responses. In this study, we construct self-assembled carrier-free nanoscale coordination polymers based on iron and methotrexate (MFe-NCPs). The low-dose-iron-induced immunogenic ferroptosis is obviously enhanced by methotrexate via inhibiting dihydrofolate reductase and abating substance reduction, respectively. Of note, MFe-NCPs sequentially promoted antigen presentation, immune activation, T cell infiltration and boosted the therapeutic effect of immune checkpoint blockade therapy.

Zoledronic Acid-Gadolinium Coordination Polymer Nanorods for Improved Tumor Radioimmunotherapy by Synergetically Inducing Immunogenic Cell Death and Reprogramming the Immunosuppressive Microenvironment.

Radiation therapy can potentially elicit a systemic immune response and cause the regression of nonirradiated tumors, and the checkpoint blockade immunotherapies have been introduced to improve their clinical response rate. However, the therapeutic benefits of radioimmunotherapy are still far from satisfactory. Herein, the self-assembled "carrier-free" coordination polymer nanorods are constructed based on gadolinium and zoledronic acid, which can deposit X-ray for improved reactive oxygen species production to induce potent immunogenic cell death (ICD), simultaneously deplete tumor-associated macrophages with regulatory cytokines inhibition, respectively. With the potent ICD induction and reprogrammed immunosuppressive microenvironment, this synergetic strategy can promote antigen presentation, immune priming and T-cell infiltration, and potentiate checkpoint blockade immunotherapies against primary, distant, and metastatic tumors.

Nanoscale coordination polymers induce immunogenic cell death by amplifying radiation therapy mediated oxidative stress.

Radiation therapy can potentially induce immunogenic cell death, thereby priming anti-tumor adaptive immune responses. However, radiation-induced systemic immune responses are very rare and insufficient to meet clinical needs. Here, we demonstrate a synergetic strategy for boosting radiation-induced immunogenic cell death by constructing gadolinium-hemin based nanoscale coordination polymers to simultaneously perform X-ray deposition and glutathione depletion. Subsequently, immunogenic cell death is induced by sensitized radiation to potentiate checkpoint blockade immunotherapies against primary and metastatic tumors. In conclusion, nanoscale coordination polymers-sensitized radiation therapy exhibits biocompatibility and therapeutic efficacy in preclinical cancer models, and has the potential for further application in cancer radio-immunotherapy.

Synthesis of functionalized 2,5-dihydropyrrole derivatives via a convenient [3 + 2] annulation of azomethine ylides with allenoates.

A convenient [3 + 2] annulation of azomethine ylides with allenoates promoted by triethylamine produced highly functionalized 2,5-dihydropyrrole derivatives in moderate to excellent yields under mild conditions. The potential utility of this reaction indicates that this reaction could be performed on the gram scale and the synthesized functionalized 2,5-dihydropyrrole derivatives could be further transformed into other interesting heterocycles. The mechanism for the transformation is a tandem ß-addition/Mannich cyclization process.

Hydroxy-Assisted Regio- and Stereoselective Synthesis of Functionalized 4-Methylenepyrrolidine Derivatives via Phosphine-Catalyzed [3 + 2] Cycloaddition of Allenoates with o-Hydroxyaryl Azomethine Ylides.

In this work, we present a new strategy for the chemo-, regio-, and stereoselective synthesis of functionalized pyrrolidine derivatives via a hydroxy-assisted phosphine-catalyzed reaction of allenoates or substituted allenoates with o-hydroxyaryl azomethine ylides that offers a wide variety of 4-methylenepyrrolidine derivatives in synthetically useful yields with high stereoselctivities under mild conditions. Remarkably, it is the first example of highly regio- and stereoselective phosphine-catalyzed [3 + 2] cycloaddition of allenoates with o-hydroxyaryl azomethine ylides.

Phosphine-Catalyzed Domino ß/γ-Additions of Benzofuranones with Allenoates: A Method for Unsymmetrical 3,3-Disubstituted Benzofuranones.

A phosphine-catalyzed domino process of benzofuranones with allenoates has been developed which furnishes highly functionalized unsymmetrical 3,3-disubstituted benzofuranones in synthetically useful yields. The mechanism for the transformation is a tandem ß-umpolung/γ-umpolung process.