Metal-Phenolic Nanomedicines Regulate T-Cell Antitumor Function for Sono-Metabolic Cancer Therapy

Bone targeted nano-drug and nano-delivery

There are currently no targeted delivery systems to satisfactorily treat bone-related disorders. Many clinical drugs consisting of small organic molecules have a short circulation half-life and do not effectively reach the diseased tissue site. This coupled with repeatedly high dose usage that leads to severe side effects. With the advance in nanotechnology, drugs contained within a nano-delivery device or drugs aggregated into nanoparticles (nano-drugs) have shown promises in targeted drug delivery. The ability to design nanoparticles to target bone has attracted many researchers to develop new systems for treating bone related diseases and even repurposing current drug therapies. In this review, we shall summarise the latest progress in this area and present a perspective for future development in the field. We will focus on calcium-based nanoparticle systems that modulate calcium metabolism and consequently, the bone microenvironment to inhibit disease progression (including cancer). We shall also review the bone affinity drug family, bisphosphonates, as both a nano-drug and nano-delivery system for bone targeted therapy. The ability to target and release the drug in a controlled manner at the disease site represents a promising safe therapy to treat bone diseases in the future.

Carrier-Free Nanodrugs: From Bench to Bedside

Carrier-free nanodrugs with extraordinary active pharmaceutical ingredient (API) loading (even 100%), avoidable carrier-induced toxicity, and simple synthetic procedures are considered as one of the most promising candidates for disease theranostics. Substantial studies and the commercial success of "carrier-free" nanocrystals have demonstrated their strong clinical potential. However, their practical translations remain challenging and are impeded by unpredictable assembly processes, insufficient delivery efficiency, and an unclear in vivo fate. In this Perspective, we systematically outline the contemporary and emerging carrier-free nanodrugs based on diverse APIs, as well as highlight their opportunities and challenges in clinical translation. Looking ahead, further improvements in design and preparation, drug delivery, in vivo efficacy, and safety of carrier-free nanomedicines are essential to facilitate their translation from the bench to bedside.

Rhein and hesperidin nanoparticles remodel tumor immune microenvironment by reducing CAFs and CCL2 secreted by CAAs for efficient triple-negative breast cancer therapy

In triple-negative breast cancer (TNBC), the tumor immune microenvironment (TIME) is a highly heterogeneous ecosystem that exerts indispensable roles in tumorigenesis and tumor progression. Cancer-associated fibroblasts (CAFs) and cancer-associated adipocytes (CAAs) are the main matrix components in the TIME of TNBC. CAFs mediate the edesmoplastic response, which is a major driver of the immunosuppressive microenvironment to promote tumor growth. In addition, CAAs, a type of tumor-educated adipocyte, participate in crosstalk with breast cancer and are capable of secreting various cytokines, adipokines and chemokines, especially C-C Motif Chemokine Ligand 2 (CCL2), resulting in changes of cancer cell phenotype and function. Therefore, how to treat tumors by regulating the CAFs and the secretion of CCL2 by CAAs in TIME is investigated here. Our research group previously found that rhein (Rhe) has been identified as effective against CAFs, while hesperidin (Hes) could effectively diminish CCL2 secretion by CAAs. Inspired by the above, we developed unique PLGA-based nanoparticles loaded with Rhe and Hes (RH-NP) using the emulsion solvent diffusion method. The RH-NP particles have an average size of 114.1 ± 0.98 nm. RH-NP effectively reduces CAFs and inhibits CCL2 secretion by CAAs, promoting increased infiltration of cytotoxic T cells and reducing immunosuppressive cell presence within tumors. This innovative, safe, low-toxic, and highly effective anti-tumor strategy could be prospective in TNBC treatment.

Metal-Coordinated NIR-II Nanoadjuvants with Nanobody Conjugation for Potentiating Immunotherapy by Tumor Metabolism Reprogramming

Immune checkpoint blockade (ICB) immunotherapy remains hampered by insufficient immunogenicity and a high-lactate immunosuppressive tumor microenvironment (TME). Herein, a nanobody-engineered NIR-II nanoadjuvant with targeting metabolic reprogramming capability is constructed for potentiating NIR-II photothermal-ferroptosis immunotherapy. Specifically, the nanoadjuvant (2DG@FS-Nb) is prepared by metallic iron ion-mediated coordination self-assembly of D-A-D type NIR-II molecules and loading of glycolysis inhibitor, 2-deoxy-D-glucose (2DG), followed by modification with aPD-L1 nanobody (Nb), which can effectively target the immunosuppressive TME and trigger in situ immune checkpoint blockade. The nanoadjuvants responsively release therapeutic components in the acidic TME, enabling the precise tumor location by NIR-II fluorescence/photoacoustic imaging while initiating NIR-II photothermal-ferroptosis therapy. The remarkable NIR-II photothermal efficiency and elevated glutathione (GSH) depletion further sensitize ferroptosis to induce severe lipid peroxidation, provoking robust immunogenic cell death (ICD) to trigger anti-tumor immune response. Importantly, the released 2DG markedly inhibits lactate generation through glycolysis obstruction. Decreased lactate efflux remodels the immunosuppressive TME by suppressing M2 macrophage proliferation and downregulating regulatory T cell levels. This work provides a new paradigm for the integration of NIR-II phototheranostics and lactate metabolism regulation into a single nanoplatform for amplified anti-tumor immunotherapy combined with ICB therapy.

Boosting Energy Deprivation by Synchronous Interventions of Glycolysis and Oxidative Phosphorylation for Bioenergetic Therapy Synergetic with Chemodynamic/Photothermal Therapy

Bioenergetic therapy is emerging as a promising therapeutic approach. However, its therapeutic effectiveness is restricted by metabolic plasticity, as tumor cells switch metabolic phenotypes between glycolysis and oxidative phosphorylation (OXPHOS) to compensate for energy. Herein, Metformin (MET) and BAY-876 (BAY) co-loaded CuFe2O4 (CF) nanoplatform (CFMB) is developed to boost energy deprivation by synchronous interventions of glycolysis and OXPHOS for bioenergetic therapy synergetic with chemodynamic/photothermal therapy (CDT/PTT). The MET can simultaneously restrain glycolysis and OXPHOS by inhibiting hexokinase 2 (HK2) activity and damaging mitochondrial function to deprive energy, respectively. Besides, BAY blocks glucose uptake by inhibiting glucose transporter 1 (GLUT1) expression, further potentiating the glycolysis repression and thus achieving much more depletion of tumorigenic energy sources. Interestingly, the upregulated antioxidant glutathione (GSH) in cancer cells triggers CFMB degradation to release Cu+/Fe2+ catalyzing tumor-overexpressed H2O2 to hydroxyl radical (∙OH), both impairing OXPHOS and achieving GSH-depletion amplified CDT. Furthermore, upon near-infrared (NIR) light irradiation, CFMB has a photothermal conversion capacity to kill cancer cells for PTT and improve ∙OH production for enhanced CDT. In vivo experiments have manifested that CFMB remarkably suppressed tumor growth in mice without systemic toxicity. This study provides a new therapeutic modality paradigm to boost bioenergetic-related therapies.

Dual-Epigenetically Relieving the MYC-Correlated Immunosuppression via an Advanced Nano-Radiosensitizer Potentiates Cancer Immuno-Radiotherapy

Cancer cells can upregulate the MYC expression to repair the radiotherapy-triggered DNA damage, aggravating therapeutic resistance and tumor immunosuppression. Epigenetic treatment targeting the MYC-transcriptional abnormality may intensively solve this clinical problem. Herein, 5-Aza (a DNA methyltransferase inhibitor) and ITF-2357 (a histone deacetylase inhibitor) are engineered into a tungsten-based nano-radiosensitizer (PWAI), to suppress MYC rising and awaken robust radiotherapeutic antitumor immunity. Individual 5-Aza depletes MYC expression but cannot efficiently awaken radiotherapeutic immunity. This drawback can be overcome by the addition of ITF-2357, which triggers cancer cellular type I interferon (IFN-I) signaling. Coupling 5-Aza with ITF-2357 ensures that PWAI does not evoke the treated model with high MYC-related immune resistance while amplifying the radiotherapeutic tumor killing, and more importantly promotes the generation of IFN-I signal-related proteins involving IFN-α and IFN-β. Unlike the radiation treatment alone, PWAI-triggered immuno-radiotherapy remarkably enhances antitumor immune responses involving the tumor antigen presentation by dendritic cells, and improves intratumoral recruitment of cytotoxic T lymphocytes and their memory-phenotype formation in 4T1 tumor-bearing mice. Downgrading the radiotherapy-induced MYC overexpression via the dual-epigenetic reprogramming strategy may elicit a robust immuno-radiotherapy.

New Ca2+ based anticancer nanomaterials trigger multiple cell death targeting Ca2+ homeostasis for cancer therapy

Calcium ion (Ca2+) is a necessary element for human and Ca2+ homeostasis plays important roles in various cellular process and functions. Recent reaches have targeted on inducing Ca2+ overload (both intracellular and transcellular) for tumor therapy. With the development of nanotechnology, nanoplatform-mediated Ca2+ overload has been safe theranostic model for cancer therapy, and defined a special calcium overload-induced tumor cell death as "calcicoptosis". However, the underlying mechanism of calcicoptosis in cancer cells remains further identification. In this review, we summarized multiple cell death types due to Ca2+ overload that induced by novel anticancer nanomaterials in tumor cells, including apoptosis, autophagy, pyroptosis, and ferroptosis. We reviewed the roles of these anticancer nanomaterials on Ca2+ homeostasis, including transcellular Ca2+ influx and efflux, and intracellular Ca2+ change in the cytosolic and organelles, and connection of Ca2+ overload with other metal ions. This review provides the knowledge of these nano-anticancer materials-triggered calcicoptosis accompanied with multiple cell death by regulating Ca2+ homeostasis, which could not only enhance their efficiency and specificity, but also enlighten to design new cancer therapeutic strategies and biomedical applications.

Recent advances in nanomedicine for metabolism-targeted cancer therapy

Metabolism denotes the sum of biochemical reactions that maintain cellular function. Different from most normal differentiated cells, cancer cells adopt altered metabolic pathways to support malignant properties. Typically, almost all cancer cells need a large number of proteins, lipids, nucleotides, and energy in the form of ATP to support rapid division. Therefore, targeting tumour metabolism has been suggested as a generic and effective therapy strategy. With the rapid development of nanotechnology, nanomedicine promises to have a revolutionary impact on clinical cancer therapy due to many merits such as targeting, improved bioavailability, controllable drug release, and potentially personalized treatment compared to conventional drugs. This review comprehensively elucidates recent advances of nanomedicine in targeting important metabolites such as glucose, glutamine, lactate, cholesterol, and nucleotide for effective cancer therapy. Furthermore, the challenges and future development in this area are also discussed.

A mitochondria-targeted anticancer copper dithiocarbamate amplifies immunogenic cuproptosis and macrophage polarization

The way that cancer cells die inspires treatment regimens and cytolytic cuproptosis induced by copper complexes, like copper(II) bis(diethyldithiocarbamate) (CuET), has emerged as a novel therapeutic target. Herein, a triphenylphosphonium-modified CuET (TPP-CuET) is designed to target mitochondrial metabolism, triggering intense immunogenic cuproptosis in breast cancer cells and remodeling tumor-associated macrophages. TPP-CuET enables an enhanced mitochondrial copper accumulation in comparison to CuET (29.0% vs. 19.4%), and severely disrupts the morphology and functions of mitochondria, encompassing the tricarboxylic acid cycle, ATP synthesis, and electron transfer chain. Importantly, it triggers amplified immunogenic death of cancer cells, and the released damage-associated molecular patterns effectively induce M1 polarization and migration of macrophages. Transcriptome analysis further reveals that TPP-CuET promotes antigen processing and presentation in cancer cells through the MHC I pathway, activating the immune response of CD8 T cells and natural killer cells. To the best of our knowledge, TPP-CuET is the first mitochondrial targeted immunogenic cuproptosis inducer and is expected to flourish in antitumor immunotherapy.

Metal-polyphenol "prison" attenuated bacterial outer membrane vesicle for chemodynamics promoted in situ tumor vaccines

As natural adjuvants, the bacterial outer membrane vesicles (OMV) hold great potential in cancer vaccines. However, the inherent immunotoxicity of OMV and the rarity of tumor-specific antigens seriously hamper the clinical translation of OMV-based cancer vaccines. Herein, metal-phenolic networks (MPNs) are used to attenuate the toxicity of OMV, meanwhile, provide tumor antigens via the chemodynamic effect induced immunogenic cell death (ICD). Specifically, MPNs are assembled on the OMV surface through the coordination reaction between ferric ions and tannic acid. The iron-based "prison" is locally collapsed in the tumor microenvironment (TME) with both low pH and high ATP features, and thus the systemic toxicity of OMV is significantly attenuated. The released ferric ions in TME promote the ICD of cancer cells through Fenton reaction and then the generation of abundant tumor antigens, which can be used to fabricate in-situ vaccines by converging with OMV. Together with the immunomodulatory effect of OMV, potent tumor repression on a bilateral tumor model is achieved with good biosafety.

Current Advances on Nanomaterials Interfering with Lactate Metabolism for Tumor Therapy

Increasing numbers of studies have shown that tumor cells prefer fermentative glycolysis over oxidative phosphorylation to provide a vast amount of energy for fast proliferation even under oxygen-sufficient conditions. This metabolic alteration not only favors tumor cell progression and metastasis but also increases lactate accumulation in solid tumors. In addition to serving as a byproduct of glycolytic tumor cells, lactate also plays a central role in the construction of acidic and immunosuppressive tumor microenvironment, resulting in therapeutic tolerance. Recently, targeted drug delivery and inherent therapeutic properties of nanomaterials have attracted great attention, and research on modulating lactate metabolism based on nanomaterials to enhance antitumor therapy has exploded. In this review, the advanced tumor therapy strategies based on nanomaterials that interfere with lactate metabolism are discussed, including inhibiting lactate anabolism, promoting lactate catabolism, and disrupting the "lactate shuttle". Furthermore, recent advances in combining lactate metabolism modulation with other therapies, including chemotherapy, immunotherapy, photothermal therapy, and reactive oxygen species-related therapies, etc., which have achieved cooperatively enhanced therapeutic outcomes, are summarized. Finally, foreseeable challenges and prospective developments are also reviewed for the future development of this field.

Human Triosephosphate Isomerase Is a Potential Target in Cancer Due to Commonly Occurring Post-Translational Modifications

Cancer involves a series of diseases where cellular growth is not controlled. Cancer is a leading cause of death worldwide, and the burden of cancer incidence and mortality is rapidly growing, mainly in developing countries. Many drugs are currently used, from chemotherapeutic agents to immunotherapy, among others, along with organ transplantation. Treatments can cause severe side effects, including remission and progression of the disease with serious consequences. Increased glycolytic activity is characteristic of cancer cells. Triosephosphate isomerase is essential for net ATP production in the glycolytic pathway. Notably, some post-translational events have been described that occur in human triosephosphate isomerase in which functional and structural alterations are provoked. This is considered a window of opportunity, given the differences that may exist between cancer cells and their counterpart in normal cells concerning the glycolytic enzymes. Here, we provide elements that bring out the potential of triosephosphate isomerase, under post-translational modifications, to be considered an efficacious target for treating cancer.