Sustained Delivery of Carfilzomib by Tannic Acid-Based Nanocapsules Helps Develop Antitumor Immunity

Nanomaterials: leading immunogenic cell death-based cancer therapies

The field of oncology has transformed in recent years, with treatments shifting from traditional surgical resection and radiation therapy to more diverse and customized approaches, one of which is immunotherapy. ICD (immunogenic cell death) belongs to a class of regulatory cell death modalities that reactivate the immune response by facilitating the interaction between apoptotic cells and immune cells and releasing specific signaling molecules, and DAMPs (damage-associated molecular patterns). The inducers of ICD can elevate the expression of specific proteins to optimize the TME (tumor microenvironment). The use of nanotechnology has shown its unique potential. Nanomaterials, due to their tunability, targeting, and biocompatibility, have become powerful tools for drug delivery, immunomodulators, etc., and have shown significant efficacy in clinical trials. In particular, these nanomaterials can effectively activate the ICD, trigger a potent anti-tumor immune response, and maintain long-term tumor suppression. Different types of nanomaterials, such as biological cell membrane-modified nanoparticles, self-assembled nanostructures, metallic nanoparticles, mesoporous materials, and hydrogels, play their respective roles in ICD induction due to their unique structures and mechanisms of action. Therefore, this review will explore the latest advances in the application of these common nanomaterials in tumor ICD induction and discuss how they can provide new strategies and tools for cancer therapy. By gaining a deeper understanding of the mechanism of action of these nanomaterials, researchers can develop more precise and effective therapeutic approaches to improve the prognosis and quality of life of cancer patients. Moreover, these strategies hold the promise to overcome resistance to conventional therapies, minimize side effects, and lead to more personalized treatment regimens, ultimately benefiting cancer treatment.

Organelle-based immunotherapy strategies for fighting against cancer

Destruction of subcellular organelles can cause dysfunction and even death of cells to elicit immune responses. In this review, the characteristics and functions of important organelles are mainly summarized. Then, the intelligent immunotherapeutic strategies and suggestions based on influencing the organelles are further highlighted. This review will provide ideas for developing novel and effective immunotherapy strategies and advance the development of cancer immunotherapy.

TAM-Hijacked Immunoreaction Rescued by Hypoxia-Pathway-Intervened Strategy for Enhanced Metastatic Cancer Immunotherapy

Immunotherapy is regarded as a prospective strategy against metastatic cancer. However, tumor-associated macrophages (TAMs), which accumulate in hypoxic tumor microenvironment, reduce the effectiveness of immunotherapy by blocking or "hijacking" the initiation of the immune response. Here, a novel tumor-targeted nanoplatform loaded with hypoxia-pathway-intervened docosahexaenoic acid (DHA) and chemotherapeutic drug carfilzomib (CFZ) is developed, which realizes the rescue of TAM-hijacked immune response and effective metastatic cancer immunotherapy. DHA is conjugated to fucoidan (Fuc) via a reduction cleavable selenylsulfide bond (SSe) for micelle preparation, and CFZ is encapsulated in the hydrophobic cores of micelles. The functionalized nanoplatforms (Fuc─SSe─DHA (FSSeD)-CFZs) induce immunogenic cell death, inhibit hypoxia-inducible factor-1α expression, and improve immunosuppression by TAM suppression. FSSeD-CFZs enhance immune response against primary tumor development and metastasis formation. In brief, the novel rescue strategy for TAM-hijacked immunoreaction by inhibiting hypoxia pathway has the potential and clinically translational significance for enhanced metastatic cancer immunotherapy.

Systemic Delivery of Paclitaxel by Find-Me Nanoparticles Activates Antitumor Immunity and Eliminates Tumors

Local delivery of immune-activating agents has shown promise in overcoming an immunosuppressive tumor microenvironment (TME) and stimulating antitumor immune responses in tumors. However, systemic therapy is ultimately needed to treat tumors that are not readily locatable or accessible. To enable systemic delivery of immune-activating agents, we employ poly(lactic-co-glycolide) (PLGA) nanoparticles (NPs) with a track record in systemic application. The surface of PLGA NPs is decorated with adenosine triphosphate (ATP), a damage-associated molecular pattern to recruit antigen-presenting cells (APCs). The ATP-conjugated PLGA NPs (NPpD-ATP) are loaded with paclitaxel (PTX), a chemotherapeutic agent inducing immunogenic cell death to generate tumor antigens in situ. We show that the NPpD-ATP retains ATP activity in hostile TME and provides a stable "find-me" signal to recruit APCs. Therefore, the PTX-loaded NPpD-ATP helps populate antitumor immune cells in TME and attenuate the growth of CT26 and B16F10 tumors better than a mixture of PTX-loaded NPpD and ATP. Combined with anti-PD-1 antibody, PTX-loaded NPpD-ATP achieves complete regression of CT26 tumors followed by antitumor immune memory. This study demonstrates the feasibility of systemic immunotherapy using a PLGA NP formulation that delivers ICD-inducing chemotherapy and an immunostimulatory signal.

Advanced manufacturing of nanoparticle formulations of drugs and biologics using microfluidics

Numerous innovative nanoparticle formulations of drugs and biologics, named nano-formulations, have been developed in the last two decades. However, methods for their scaled-up production are still lagging, as the amount needed for large animal tests and clinical trials is typically orders of magnitude larger. This manufacturing challenge poses a critical barrier to successfully translating various nano-formulations. This review focuses on how microfluidics technology has become a powerful tool to overcome this challenge by synthesizing various nano-formulations with improved particle properties and product purity in large quantities. This microfluidic-based manufacturing is enabled by microfluidic mixing, which is capable of the precise and continuous control of the synthesis of nano-formulations. We further discuss the specific applications of hydrodynamic flow focusing, a staggered herringbone micromixer, a T-junction mixer, a micro-droplet generator, and a glass capillary on various types of nano-formulations of polymeric, lipid, inorganic, and nanocrystals. Various separation and purification microfluidic methods to enhance the product purity are reviewed, including acoustofluidics, hydrodynamics, and dielectrophoresis. We further discuss the challenges of microfluidics being used by broader research and industrial communities. We also provide future outlooks of its enormous potential as a decentralized approach for manufacturing nano-formulations.

A manual controlled theranostic nanoplatform with real-time photoacoustic quantification of drug release for chemophotothermal therapy

The development of intelligent nanodrug delivery systems that can visually guide the on-demand quantitative control of drug release has received extensive attention. Herein, two chemotherapeutic drugs, gallic acid and 5-fluorouracil, and Fe(III) were selected to prepare nanomedicine GF-Fe via polyphenol-metal self-assembly and infinite coordination of drug-metal. GF-Fe has good biocompatibility, photothermal properties and photoacoustic (PA) signals. When deferoxamine (DFO) was artificially applied and interacted with GF-Fe, GF-Fe began to disassemble, gallic acid and 5-fluorouracil were gradually released, while the PA signal of the nanomedicine decayed synchronously. Based on this, the relationship between the intensity of the PA signal and the drug release amount was established, so as to realize the precise quantitative control of the drug release in real-time under the guidance of PA imaging. Besides, the combined effect of the two therapeutic drugs in combination with photothermal therapy (PTT) can improve the therapeutic effect, resulting in significant superadditiveness. This nanoplatform constructed by facile synthesis provided good clinical translation potential for the implementation of precise multimodal combination therapy strategies for tumors.

Polyphenol-Based Nanosystems for Next-Generation Cancer Therapy: Multifunctionality, Design, and Challenges

With the continuous updating of cancer treatment methods and the rapid development of precision medicine in recent years, there are higher demands for advanced and versatile drug delivery systems. Scientists are committed to create greener and more effective nanomedicines where the carrier is no longer limited to a single function of drug delivery. Polyphenols, which can act as both active ingredients and fundamental building blocks, are being explored as potential multifunctional carriers that are efficient and safe for design purposes. Due to their intrinsic anticancer activity, phenolic compounds have shown surprising expressiveness in ablation of tumor cells, overcoming cancer multidrug resistance (MDR), and enhancing immunotherapeutic efficacy. This review provides an overview of recent advances in the design, synthesis, and application of versatile polyphenol-based nanosystems for cancer therapy in various modes. Moreover, the merits of polyphenols and the challenges for their clinical translation are also discussed, and it is pointed out that the novel polyphenol delivery system requires further optimization and validation.

Tumor Abnormality-Oriented Nanomedicine Design

Anticancer nanomedicines have been proven effective in mitigating the side effects of chemotherapeutic drugs. However, challenges remain in augmenting their therapeutic efficacy. Nanomedicines responsive to the pathological abnormalities in the tumor microenvironment (TME) are expected to overcome the biological limitations of conventional nanomedicines, enhance the therapeutic efficacies, and further reduce the side effects. This Review aims to quantitate the various pathological abnormalities in the TME, which may serve as unique endogenous stimuli for the design of stimuli-responsive nanomedicines, and to provide a broad and objective perspective on the current understanding of stimuli-responsive nanomedicines for cancer treatment. We dissect the typical transport process and barriers of cancer drug delivery, highlight the key design principles of stimuli-responsive nanomedicines designed to tackle the series of barriers in the typical drug delivery process, and discuss the "all-into-one" and "one-for-all" strategies for integrating the needed properties for nanomedicines. Ultimately, we provide insight into the challenges and future perspectives toward the clinical translation of stimuli-responsive nanomedicines.

Promotion of ICD via Nanotechnology

Immunotherapy represents the most promising treatment strategy for cancer, but suffers from compromised therapeutic efficiency due to low immune activity of tumor cells and an immunosuppressive microenvironment, which significantly hampers the clinical translations of this treatment strategy. To promote immunotherapy with desired therapeutic efficiency, immunogenic cell death (ICD), a particular type of death capable of reshaping body's antitumor immune activity, has drawn considerable attention due to the potential to stimulate a potent immune response. Still, the potential of ICD effect remains unsatisfactory because of the intricate tumor microenvironment and multiple drawbacks of the used inducing agents. ICD has been thoroughly reviewed so far with a general classification of ICD as a kind of immunotherapy strategy and repeated discussion of the related mechanism. However, there are no published reviews, to the authors' knowledge, providing a systematic summarization on the enhancement of ICD via nanotechnology. For this purpose, this review first discusses the four stages of ICD according to the development mechanisms, followed by a comprehensive description on the use of nanotechnology to enhance ICD in the corresponding four stages. The challenges of ICD inducers and possible solutions are finally summarized for future ICD-based enhanced immunotherapy.

A timescale-guided microfluidic synthesis of tannic acid-FeIII network nanocapsules of hydrophobic drugs

Many drugs are poorly water-soluble and suffer from low bioavailability. Metal-phenolic network (MPN), a hydrophilic thin layer such as tannic acid (TA)-FeIII network, has been recently used to encapsulate hydrophobic drugs to improve their bioavailability. However, it remains challenging to synthesize nanocapsules of a wide variety of hydrophobic drugs and to scale up the production in a continuous manner. Here, we present a microfluidic synthesis method to continuously produce TA-FeIII network nanocapsules of hydrophobic drugs. We hypothesize that nanocapsules can continuously be formed only when the microfluidic mixing timescale is shorter than the drug's nucleation timescale. The hypothesis was tested on three hydrophobic drugs - paclitaxel, curcumin, and vitamin D with varying solubility and nucleation timescale. The proposed mechanism was validated by successfully predicting the synthesis outcomes. The microfluidically-synthesized nanocapsules had well-controlled sizes of 100-200 nm, high drug loadings of 40-70%, and a throughput of up to 70 mg hr-1 per channel. The release kinetics, cellular uptake, and cytotoxicity were further evaluated. The effect of coating constituents on nanocapsule properties were characterized. Fe content of nanocapsules was reported. The stability of nanocapsules at different temperatures and pHs were also tested. The results suggest that the present method can provide a quantitative guideline to predictively design a continuous synthesis scheme for hydrophobic drug encapsulation via MPN nanocapsules with scaled-up capability.

Recent Advances of Fe(III)/Fe(II)-MPNs in Biomedical Applications

Metal-phenolic networks (MPNs) are a new type of nanomaterial self-assembled by metal ions and polyphenols that have been developed rapidly in recent decades. They have been widely investigated, in the biomedical field, for their environmental friendliness, high quality, good bio-adhesiveness, and bio-compatibility, playing a crucial role in tumor treatment. As the most common subclass of the MPNs family, Fe-based MPNs are most frequently used in chemodynamic therapy (CDT) and phototherapy (PTT), where they are often used as nanocoatings to encapsulate drugs, as well as good Fenton reagents and photosensitizers to improve tumor therapeutic efficiency substantially. In this review, strategies for preparing various types of Fe-based MPNs are first summarized. We highlight the advantages of Fe-based MPNs under the different species of polyphenol ligands for their application in tumor treatments. Finally, some current problems and challenges of Fe-based MPNs, along with a future perspective on biomedical applications, are discussed.

Bimetallic infinite coordination nanopolymers via phototherapy and STING activation for eliciting robust antitumor immunity

Phototherapy can trigger immunogenic cell death of tumors in situ, whereas it is virtually impossible to eradicate the tumor due to the intrinsic resistance and inefficient anti-tumor immunity. To overcome these limitations, novel bimetallic infinite coordination nanopolymers (TA-Fe/Mn-OVA@MB NPs) were synthesized using model antigen ovalbumin (OVA) as a template to assemble tannic acid (TA) and bi-metal, supplemented with methylene blue (MB) surface absorption. The formulated TA-Fe/Mn-OVA@MB NPs possess excellent photothermal and photodynamic therapy (PTT/PDT) performance, which is adequate to destroy tumor cells by physical and chemical attack. Especially, these TA-Fe/Mn-OVA@MB NPs are capability of promoting the dendritic cells (DCs) maturation and antigen presentation via manganese-mediated cGAS-STING pathway activation, finally activating cytotoxicity T lymphocyte and promoting memory T lymphocyte differentiation in the peripheral lymphoid organs. In conclusion, this research offers a versatile metal-polyphenol nanoplatform to integrate functional metals and therapeutic molecule for topical phototherapy and robust anti-tumor immune activation.

Composite Hydrogel for Spatiotemporal Lipid Intervention of Tumor Milieu

Induction of immunogenic cell death (ICD) plays crucial roles in cancer immunotherapy, whereas its efficacy is severely compromised by redundant antioxidant defenses in cancer cells and aberrant lipid metabolism in immunosuppressive cell populations. In this work, it is found that hollow mesoporous CuS nanoparticles (NPs) possess an intrinsic capacity of inhibiting glutathione peroxidase 4 (GPX4). When loaded with an inhibitor of the ferroptosis suppressor protein 1 (FSP1), these NPs block two parallel redox systems and cooperate with near-infrared irradiation to reinforce ICD. A hydrogel co-delivering cancer-cell-targeting CuS NPs and immunosuppressive-cell-targeting sulfo-N-succinimidyl oleate (SSO) for spatiotemporal lipid intervention i further fabricated. While the CuS NPs augment ICD via synergistic lipid peroxidation, SSO reinstates immune perception via lipid metabolic reprogramming, thereby coordinately triggering robust innate and adaptive immunity to restrain tumor growth, relapse, and metastasis. This study provides an immunometabolic therapy via orchestrated lipid modulation in the tumor milieu.

Hybrid Nanomaterials for Cancer Immunotherapy

Nano-immunotherapy has been recognized as a highly promising strategy for cancer treatment in recent decades, which combines nanotechnology and immunotherapy to combat against tumors. Hybrid nanomaterials consisting of at least two constituents with distinct compositions and properties, usually organic and inorganic, have been engineered with integrated functions and enormous potential in boosting cancer immunotherapy. This review provides a summary of hybrid nanomaterials reported for cancer immunotherapy, including nanoscale metal-organic frameworks, metal-phenolic networks, mesoporous organosilica nanoparticles, metallofullerene nanomaterials, polymer-lipid, and biomacromolecule-based hybrid nanomaterials. The combination of immunotherapy with chemotherapy, chemodynamic therapy, radiotherapy, radiodynamic therapy, photothermal therapy, photodynamic therapy, and sonodynamic therapy based on hybrid nanomaterials is also discussed. Finally, the current challenges and the prospects for designing hybrid nanomaterials and their application in cancer immunotherapy are outlined.

Metal-phenolic networks acted as a novel bio-filler of a barrier membrane to improve guided bone regeneration via manipulating osteoimmunomodulation

A guided bone tissue regeneration membrane (GBRM) is traditionally viewed as an inert physical barrier to isolate soft tissue from the bone defect area. However, as a "foreign body", the implantation of a GBRM would inevitably modulate immune response and subsequently affect bone dynamics. Herein, we developed strontium ion (Sr²⁺)-based metal-phenolic network complexes (MPNs) as a novel type of bio-filler to manipulate the osteoimmunomodulation of the advanced GBRM. For controllable delivery of Sr²⁺ depending on the difference in affinity between phenolic ligands and Sr²⁺, tannic acid (TA), epigallocatechin gallate (EGCG), and epigallocatechin (EGC) were selected to chelate with Sr²⁺. The formed MPNs were incorporated into PCL nanofibrous membranes by blending electrospinning. Among them, TA/Sr based MPN particles displayed the most sustainable release profile of phenolic ligands and Sr²⁺. Further investigations demonstrated that Sr²⁺ could not only directly promote osteogenic differentiation of BMSCs, but also manipulate an anti-inflammatory osteoimmune microenvironment in a synergistic manner with TA, thus enhancing osteogenesis and inhibiting bone resorption. The rat alveolar bone defect model also confirmed that the TA/Sr nanoparticle modified membrane displayed better bone regeneration performance than the pure PCL membrane via inhibiting bone resorption. This work provides a new platform for controllable delivery of bioactive nutrient elements, and holds great promise for advancing multi-functional biocomposites.

Size optimization of carfilzomib nanocrystals for systemic delivery to solid tumors

Carfilzomib (CFZ) is a second-generation proteasome inhibitor effective in blood cancer therapy. However, CFZ has shown limited efficacy in solid tumor therapy due to the short half-life and poor tumor distribution. Albumin-coated nanocrystal (NC) formulation was shown to improve the circulation stability of CFZ, but its antitumor efficacy remained suboptimal. We hypothesize that NC size reduction is critical to the formulation safety and efficacy as the small size would decrease the distribution in the reticuloendothelial system (RES) and selectively increase the uptake by tumor cells. We controlled the size of CFZ-NCs by varying the production parameters in the crystallization-in-medium method and compared the size-reduced CFZ-NCs (z-average of 168 nm, NC₁₆₈) with a larger counterpart (z-average of 325 nm, NC₃₂₅) as well as the commercial CFZ formulation (CFZ-CD). Both CFZ-NCs showed similar or higher cytotoxicity than CFZ-CD against breast cancer cells. NC₁₆₈ showed greater uptake by cancer cells, less uptake by macrophages and lower immune cell toxicity than NC₃₂₅ or CFZ-CD. NC₁₆₈, but not NC₃₂₅, showed a similar safety profile to CFZ-CD in vivo. The biodistribution and antitumor efficacy of CFZ-NCs in mice were also size-dependent. NC₁₆₈ showed greater antitumor efficacy and tumor accumulation but lower RES accumulation than NC₃₂₅ in 4T1 breast cancer model. These results support that NC formulation with an optimal particle size can improve the therapeutic efficacy of CFZ in solid tumors.

An ischemia-homing bioengineered nano-scavenger for specifically alleviating multiple pathogeneses in ischemic stroke

BACKGROUND

Ischemic stroke is one of the most serious global public health problems. However, the performance of current therapeutic regimens is limited due to their poor target specificity, narrow therapeutic time window, and compromised therapeutic effect. To overcome these barriers, we designed an ischemia-homing bioengineered nano-scavenger by camouflaging a catalase (CAT)-loaded self-assembled tannic acid (TA) nanoparticle with a M2-type microglia membrane (TPC@M2 NPs) for ischemic stroke treatment.

RESULTS

The TPC@M2 NPs can on-demand release TA molecules to chelate excessive Fe2+, while acid-responsively liberating CAT to synergistically scavenge multiple ROS (·OH, ·O2-, and H2O2). Besides, the M2 microglia membrane not only can be served as bioinspired therapeutic agents to repolarize M1 microglia into M2 phenotype but also endows the nano-scavenger with ischemia-homing and BBB-crossing capabilities.

CONCLUSIONS

The nano-scavenger for specific clearance of multiple pathogenic elements to alleviate inflammation and protect neurons holds great promise for combating ischemic stroke and other inflammation-related diseases.

Targeted NIR-responsive theranostic immuno-nanomedicine combined TLR7 agonist with immune checkpoint blockade for effective cancer photothermal immunotherapy

Nanomedicine with immunotherapy offers opportunities to target cancer in an effective manner; however, it remains challenging. We herein report a photothermal material loaded with immune-adjuvant combined immune checkpoint blockade for efficient cancer immunotherapy to target estrogen receptor-positive (ER⁺) breast cancer (BC). Endoxifen (END) expressly targets ER⁺ breast cancer cells. As a proof of concept of a targeting ER⁺ agent, END/NIR-responsive polyaniline (PANi)/a toll-like-receptor-7 agonist imiqumoid (R837) activating immune response co-encapsulated nanoparticles were formed as END-PANi-PVP@R837 NPs and found to be very appropriate as an NIR-responsive photothermal platform for versatile immunogenic cell death (ICD) in combination with an immune checkpoint PD-L1 blockade for development as an immunotherapy strategy. In this study, we concentrate on the therapeutic tactic of combining anti-PD-L1 with NPs, not only ablating cancer cells upon NIR irradiation but also providing strong anti-cancer immunity to destroy tumor progression after treatment. In both in vitro and in vivo experiments it was demonstrated that NPs could efficiently activate PTT to induce an immune response and immune resistance based on the PD-L1 checkpoint to ablate the tumor and inhibit tumor recurrence. We confirm the potency of the NPs, which exhibit high photothermal conversion efficacy and stability. The results demonstrate that the NP combination suppresses tumor cell growth at the tumor margin beyond effective PTT and immunotherapy.

Chemo-Phototherapy with Carfilzomib-Encapsulated TiN Nanoshells Suppressing Tumor Growth and Lymphatic Metastasis

The design of nanomedicine for cancer therapy, especially the treatment of tumor metastasis has received great attention. Proteasome inhibition is accepted as a new strategy for cancer therapy. Despite being a big breakthrough in multiple myeloma therapy, carfilzomib (CFZ), a second-in-class proteasome inhibitor is still unsatisfactory for solid tumor and metastasis therapy. In this study, hollow titanium nitride (TiN) nanoshells are synthesized as a drug carrier of CFZ. The TiN nanoshells have a high loading capacity of CFZ, and their intrinsic inhibitory effect on autophagy synergistically enhances the activity of CFZ. Due to an excellent photothermal conversion efficiency in the second near-infrared (NIR-II) region, TiN nanoshell-based photothermal therapy further induces a synergistic anticancer effect. In vivo study demonstrates that TiN nanoshells readily drain into the lymph nodes, which are responsible for tumor lymphatic metastasis. The CFZ-loaded TiN nanoshell-based chemo-photothermal therapy combined with surgery offers a remarkable therapeutic outcome in greatly inhibiting further metastatic spread of cancer cells. These findings suggest that TiN nanoshells act as an efficient carrier of CFZ for realizing enhanced outcomes for proteasome inhibitor-based cancer therapy, and this work also presents a "combined chemo-phototherapy assisted surgery" strategy, promising for future cancer treatment.

Submolecular Ligand Size and Spacing for Cell Adhesion

Cell adhesion occurs when integrin recognizes and binds to Arg-Gly-Asp (RGD) ligands present in fibronectin. In this work, submolecular ligand size and spacing are tuned via template-mediated in situ growth of nanoparticles for dynamic macrophage modulation. To tune liganded gold nanoparticle (GNP) size and spacing from 3 to 20 nm, in situ localized assemblies of GNP arrays on nanomagnetite templates are engineered. 3 nm-spaced ligands stimulate the binding of integrin, which mediates macrophage-adhesion-assisted pro-regenerative polarization as compared to 20 nm-spaced ligands, which can be dynamically anchored to the substrate for stabilizing integrin binding and facilitating dynamic macrophage adhesion. Increasing the ligand size from 7 to 20 nm only slightly promotes macrophage adhesion, not observed with 13 nm-sized ligands. Increasing the ligand spacing from 3 to 17 nm significantly hinders macrophage adhesion that induces inflammatory polarization. Submolecular tuning of ligand spacing can dominantly modulate host macrophages.

All-in-one approaches for triple-negative breast cancer therapy: metal-phenolic nanoplatform for MR imaging-guided combinational therapy

BACKGROUND

Conventional chemotherapy has poor efficacy in triple-negative breast cancer (TNBC) which is highly heterogeneous and aggressive. Imaging-guided therapy is usually combined with diverse treatment modalities, could realize the integration of diagnosis and treatments. Therefore, the primary challenge for combinational therapy is designing proper delivery systems to accomplish multiple synergistic effects.

RESULTS

Herein, a facile nanoplatform was manufactured to fulfill the all-in-one approaches for TNBC combinational therapy. Fe³⁺-based metal-phenolic networks (MPNs) with bovine serum albumin (BSA) modification served as drug delivery carriers to encapsulate bleomycin (BLM), forming BFE@BSA NPs. The self-assembly mechanism, pH-responsive drug release behavior, and other physicochemical properties of this system were characterized. The potential of BFE@BSA NPs as photothermal transduction agents and magnetic resonance imaging (MRI) contrast agents was explored. The synergistic anti-tumor effects consisting of BLM-induced chemotherapy, Fenton reactions-mediated chemodynamic therapy, and photothermal therapy-induced apoptosis were studied both in vitro and in vivo. Once internalized into tumor cells, released BLM could cause DNA damage, while Fenton reactions were initiated to produce highly toxic •OH. Upon laser irradiation, BFE@BSA NPs could convert light into heat to achieve synergistic effects. After intravenous administration, BFE@BSA NPs exhibited great therapeutic effects in 4T1 tumor xenograft model. Moreover, as T₁-weighted MRI contrast agents, BFE@BSA NPs could provide diagnosis and treatment monitoring for individualized precise therapy.

CONCLUSIONS

A nano-system that integrated imaging and combinational therapy (chemotherapy, chemodynamic therapy and photothermal therapy) were developed to kill the tumor and monitor therapeutic efficacy. This strategy provided an all-in-one theranostic nanoplatform for MRI-guided combinational therapy against TNBC.

Combination of oxaliplatin and POM-1 by nanoliposomes to reprogram the tumor immune microenvironment

Some chemotherapy can damage tumor cells, releasing damage-related molecular patterns including ATP to improve immunological recognition against the tumor by immunogenic cell death (ICD). However, the immune-stimulating ATP may be rapidly degraded into immunosuppressive adenosine by highly expressed CD39 and CD73 in the tumor microenvironment, which leads to immune escape. Based on the above paradox, a liposome nanoplatform combined with ICD inducer (oxaliplatin) and CD39 inhibitor (POM-1) is designed for immunochemotherapy. The liposomes efficiently load the phospholipid-like oxaliplatin prodrug, and the cationic charged surface could adsorb POM-1. Rationally designed DSPE-PEG_n-pep, on the one hand, could cover and hide POM-1 to avoid systematic toxicity and, on the other, achieve a response and charge reversal to favor POM-1 shedding and tumor deep penetration. This combination maximizes the ICD effect, and takes two-pronged advantage of stimulating the immune response and relieving immune suppression. The designed POL can effectively inhibit the growth of in situ, lung metastasis and postoperative recurrence melanoma model and form long-term immune memory. With the powerful clinical transformation potential of nanoliposome platforms, this new synergistic strategy is expected to enhance anticancer effects safely and effectively.

Enhancing cancer chemo-immunotherapy by biomimetic nanogel with tumor targeting capacity and rapid drug-releasing in tumor microenvironment

In the development of chemo-immunotherapy, many efforts have been focusing on designing suitable carriers to realize the co-delivery of chemotherapeutic and immunotherapeutic with different physicochemical properties and mechanisms of action. Besides, rapid drug release at the tumor site with minimal drug degradation is also essential to facilitate the antitumor effect in a short time. Here, we reported a cancer cell membrane-coated pH-responsive nanogel (NG@M) to co-deliver chemotherapeutic paclitaxel (PTX) and immunotherapeutic agent interleukin-2 (IL-2) under mild conditions for combinational treatment of triple-negative breast cancer. In the designed nanogels, the synthetic copolymer PDEA-co-HP-β-cyclodextrin-co-Pluronic F127 and charge reversible polymer dimethylmaleic anhydride-modified polyethyleneimine endowed nanogels with excellent drug-loading capacity and rapid responsive drug-releasing behavior under acidic tumor microenvironment. Benefited from tumor homologous targeting capacity, NG@M exhibited 4.59-fold higher accumulation at the homologous tumor site than heterologous cancer cell membrane-coated NG. Rapidly released PTX and IL-2 enhanced the maturation of dendritic cells and quickly activated the antitumor immune response in situ, followed by prompted infiltration of immune effector cells. By the combined chemo-immunotherapy, enhanced antitumor effect and efficient pulmonary metastasis inhibition were achieved with a prolonged median survival rate (39 days).

Manipulating Nanoparticle Aggregates Regulates Receptor-Ligand Binding in Macrophages

The receptor-ligand interactions in cells are dynamically regulated by modulation of the ligand accessibility. In this study, we utilize size-tunable magnetic nanoparticle aggregates ordered at both nanometer and atomic scales. We flexibly anchor magnetic nanoparticle aggregates of tunable sizes over the cell-adhesive RGD ligand (Arg-Gly-Asp)-active material surface while maintaining the density of dispersed ligands accessible to macrophages at constant. Lowering the accessible ligand dispersity by increasing the aggregate size at constant accessible ligand density facilitates the binding of integrin receptors to the accessible ligands, which promotes the adhesion of macrophages. In high ligand dispersity, distant magnetic manipulation to lift the aggregates (which increases ligand accessibility) stimulates the binding of integrin receptors to the accessible ligands available under the aggregates to augment macrophage adhesion-mediated pro-healing polarization both in vitro and in vivo. In low ligand dispersity, distant control to drop the aggregates (which decreases ligand accessibility) repels integrin receptors away from the aggregates, thereby suppressing integrin receptor-ligand binding and macrophage adhesion, which promotes inflammatory polarization. Here, we present "accessible ligand dispersity" as a novel fundamental parameter that regulates receptor-ligand binding, which can be reversibly manipulated by increasing and decreasing the ligand accessibility. Limitless tuning of nanoparticle aggregate dimensions and morphology can offer further insight into the regulation of receptor-ligand binding in host cells.

Fibronectin-Coated Metal-Phenolic Networks for Cooperative Tumor Chemo-/Chemodynamic/Immune Therapy via Enhanced Ferroptosis-Mediated Immunogenic Cell Death

The development of nanomedicine formulations to overcome the disadvantages of traditional chemotherapeutic drugs and integrate cooperative theranostic modes still remains challenging. Herein, we report the facile construction of a multifunctional theranostic nanoplatform based on doxorubicin (DOX)-loaded tannic acid (TA)-iron (Fe) networks (for short, TAF) coated with fibronectin (FN) for combination tumor chemo-/chemodynamic/immune therapy under the guidance of magnetic resonance (MR) imaging. We show that the DOX-TAF@FN nanocomplexes created through in situ coordination of TA and Fe(III) and physical coating with FN have a mean particle size of 45.0 nm, are stable, and can release both DOX and Fe in a pH-dependent manner. Due to the coexistence of the TAF network and DOX, significant immunogenic cell death can be caused through enhanced ferroptosis of cancer cells via cooperative Fe-based chemodynamic therapy and DOX chemotherapy. Through further treatment with programmed cell death ligand 1 antibody for an immune checkpoint blockade, the tumor treatment efficacy and the associated immune response can be further enhanced. Meanwhile, with FN-mediated targeting, the DOX-TAF@FN platform can specifically target tumor cells with high expression of α_vβ₃ integrin. Finally, the TAF network also enables the DOX-TAF@FN to have an r₁ relaxivity of 6.1 mM^-1 s^-1 for T₁-weighted MR imaging of tumors. The developed DOX-TAF@FN nanocomplexes may represent an updated multifunctional nanosystem with simple compositions for cooperative MR imaging-guided targeted chemo-/chemodynamic/immune therapy of tumors.

Dynamic Ligand Screening by Magnetic Nanoassembly Modulates Stem Cell Differentiation

In native microenvironment, diverse physical barriers exist to dynamically modulate stem cell recruitment and differentiation for tissue repair. In this study, nanoassembly-based magnetic screens of various sizes are utilized, and they are elastically tethered over an RGD ligand (cell-adhesive motif)-presenting material surface to generate various nanogaps between the screens and the RGDs without modulating the RGD density. Large screens exhibiting low RGD distribution stimulate integrin clustering to facilitate focal adhesion, mechanotransduction, and differentiation of stem cells, which are not observed with small screens. Magnetic downward pulling of the large screens decreases the nanogaps, which dynamically suppress the focal adhesion, mechanotransduction, and differentiation of stem cells. Conversely, magnetic upward pulling of the small screens increases the nanogaps, which dynamically activates focal adhesion, mechanotransduction, and differentiation of stem cells. This regulation mechanism is also shown to be effective in the microenvironment in vivo. Further diversifying the geometries of the physical screens can further enable diverse modalities of multifaceted and safe unscreening of the distributed RGDs to unravel and modulate stem cell differentiation for tissue repair.

Cancer-Cell-Biomimetic Nanoparticles for Targeted Therapy of Multiple Myeloma Based on Bone Marrow Homing

Multiple myeloma (MM) is the second most common hematological malignancy. It is characterized by abnormal transformation and uncontrolled clonal proliferation of malignant plasma cells in the bone marrow (BM), which can destroy bone structure and inhibit hematopoiesis. Although there are new therapeutic methods, they are not curative, mainly because it is difficult to deliver an effective amount of drug to BM, leading to a failure to eradicate MM cells inside the BM. BM homing is an important and unique characteristic of MM cells and it is mainly affected by surface molecules on the tumor cell membrane. Inspired by this mechanism, an MM-mimicking nanocarrier is developed by coating bortezomib (BTZ)-loaded poly(ε-caprolactone)-poly(ethylene glycol)-poly(ε-caprolactone) (PCEC) nanoparticles with the MM cell membrane. The MM-mimicking nanoparticles can enter the BM based on BM homing as a "Trojan horse" and target the tumor cells through homologous targeting. In this way, drug availability at the myeloma site is enhanced so as to inhibit MM growth. In addition, these MM-mimicking nanoparticles can escape phagocytosis by the MPS and have a long circulation effect. The in vivo therapeutic results demonstrate an excellent treatment efficacy for MM. Accordingly, this strategy may be a promising platform for the treatment of MM.

Critical quality attributes in the development of therapeutic nanomedicines toward clinical translation

Nanomedicine is a rapidly emerging field with several breakthroughs in the therapeutic drug delivery application. The unique properties of the nanoscale delivery systems offer huge advantages to their payload such as solubilization, increased bioavailability, and improved pharmacokinetics with an overall goal of enhanced therapeutic index. Nanomedicine has the potential for integrating and enabling new therapeutic modalities. Several nanoparticle-based drug delivery systems have been granted approval for clinical use based on their outstanding clinical outcomes. Nanomedicine faces several challenges that hinder the realization of its full potential. In this review, we discuss the critical formulation- and biological-related quality features that significantly influence the performance of nanoparticulate systems in vivo. We also discuss the quality-by-design approach in the pharmaceutical manufacturing and its implementation in the nanomedicine. A deep understanding of these nanomedicine quality checkpoints and a systematic design that takes them into consideration will hopefully expedite the clinical translation process. Graphical abstract.

Low Dose Soft X-Ray Remotely Triggered Lanthanide Nanovaccine for Deep Tissue CO Gas Release and Activation of Systemic Anti-Tumor Immunoresponse

Gas-based therapy has emerged as a new green therapy strategy for anti-tumor treatment. However, the therapeutic efficacy is still restricted by the deep tissue controlled release, poor lymphocytic infiltration, and inherent immunosuppressive tumor microenvironment (TME). Herein, a new type of nanovaccine is designed by integrating low dose soft X-ray-triggered CO releasing lanthanide scintillator nanoparticles (ScNPs: NaLuF4 :Gd,Tb@NaLuF4 ) with photo-responsive CO releasing moiety (PhotoCORM) for synergistic CO gas/immuno-therapy of tumors. The designed nanovaccine presents significantly boosted radioluminescence and enables deep tissue CO generation at unprecedented tissue depths of 5 cm under soft X-ray irradiation. Intriguingly, CO as a superior immunogenic cell death (ICD) inducer further reverses the deep tissue immunosuppressive TME and concurrently activates adaptive anti-tumor immunity through efficient reactive oxygen species (ROS) generation. More importantly, the designed nanovaccine presents efficient growth inhibition of both local and distant tumors via a soft X-ray activated systemic anti-tumor immunoresponse. This work provides a new strategy of designing anti-tumor nanovaccines for synergistic deep tissue gas-therapy and remote soft X-ray photoactivation of the immune response.

Phenolic-enabled nanotechnology: versatile particle engineering for biomedicine

Phenolics are ubiquitous in nature and have gained immense research attention because of their unique physiochemical properties and widespread industrial use. In recent decades, their accessibility, versatile reactivity, and relative biocompatibility have catalysed research in phenolic-enabled nanotechnology (PEN) particularly for biomedical applications which have been a major benefactor of this emergence, as largely demonstrated by polydopamine and polyphenols. Therefore, it is imperative to overveiw the fundamental mechanisms and synthetic strategies of PEN for state-of-the-art biomedical applications and provide a timely and comprehensive summary. In this review, we will focus on the principles and strategies involved in PEN and summarize the use of the PEN synthetic toolkit for particle engineering and the bottom-up synthesis of nanohybrid materials. Specifically, we will discuss the attractive forces between phenolics and complementary structural motifs in confined particle systems to synthesize high-quality products with controllable size, shape, composition, as well as surface chemistry and function. Additionally, phenolic's numerous applications in biosensing, bioimaging, and disease treatment will be highlighted. This review aims to provide guidelines for new scientists in the field and serve as an up-to-date compilation of what has been achieved in this area, while offering expert perspectives on PEN's use in translational research.

Enhancing Cancer Immunotherapy Treatment Goals by Using Nanoparticle Delivery System

Recently, there has been an incredible increase in research about the abnormal growth of cells (neoplasm), focusing on the management, treatment and preventing reoccurrence. It has been understood that the natural defense system, composed of a variety of immune defensive cells, does not just limit its function in eliminating neoplastic cells, but also controls the growth and spread of tumor cells of different kinds to other parts of the body. Cancer immunotherapy, is a cancer treatment plan that educates the body’s defensive system to forestall, control, and eliminate tumor cells. The effectiveness of immunotherapy is achieved, to its highest efficacy, by the use of nanoparticles (NPs) for precise and timely delivery of immunotherapies to specific targeted neoplasms, with less or no harm to the healthy cells. Immunotherapies have been affirmed in clinical trials as a cancer regimen for various types of cancers, the side effects resulting from imprecise and non-targeted conveyance is well managed with the use of nanoparticles. Nonetheless, we will concentrate on enhancing cancer immunotherapy approaches by the use of nanoparticles for the productivity of antitumor immunity. Nanoparticles will be presented and utilized as an objective immunotherapy delivery system for high exactness and are thus a promising methodology for cancer treatment.

Metal-phenolic networks for cancer theranostics

Metal-phenolic networks (MPNs) have shown promising potential in biomedical applications since they provide a rapid, simple and robust way to construct multifunctional nanoplatforms. As a novel nanomaterial self-assembled from metal ions and polyphenols, MPNs can be prepared to assist the theranostics of cancer owing to their bio-adhesiveness, good biocompatibility, versatile drug loading, and stimuli-responsive profile. This Critical Review aims to summarize recent progress in MPN-based nanoplatforms for multimodal tumor therapy and imaging. First, the advantages of MPNs as drug carriers are summarized. Then, various tumor therapeutic modalities based on MPNs are introduced. Next, MPN-based theranostic systems are reviewed. In terms of in vivo applications, specific attention is paid to their biosafety, biodistribution, as well as excretion. Finally, some problems and limitations of MPNs are discussed, along with a future perspective on the field.

Rational design of metal-organic frameworks to deliver methotrexate for targeted rheumatoid arthritis therapy

Methotrexate (MTX) has been used as an anchor drug for the treatment of rheumatoid arthritis (RA), while the patients with chronic MTX administration suffer from severe side-effects. To this end, targeted delivery of MTX by nanomedicine has attracted great interest. In this work, we aimed to employ metal-organic frameworks (MOFs) as nanocarrier to deliver MTX by virtue of its facile and green preparation and exceptionally high drug loading. While MTX could be easily and effectively loaded via different MOF construction strategies, such as direct coordination, physical encapsulation, and covalent conjugation, we found that most of the MTX loading MOFs showed premature and burst drug release, attributable to the unstable coordination between MTX and metals. To address this issue, we rationally designed the MOFs by conjugating MTX with tannic acid (TA) at 2:1 M ratio and then coordinating with ferric ion (Fe³⁺), followed by surface modification of hyaluronic acid (HA). The resulting MOFs achieved ultra-high drug loading (45%) and sustained drug release, and could selectively recognize the diseased cells for anti-inflammatory effect. The in vivo therapeutic evaluation suggested that the MOFs could enhance the anti-rheumatic activity of MTX while minimizing its toxic effects by targeted drug delivery, resulting in improved therapeutic index. This work provides a biocompatible nano-platform to deliver MTX for RA treatment, and importantly, calls for special attention to the gap between MOFs design and their biological applications, and the gap needs to be filled by careful evaluation of in vivo stability and burst drug release.

Large and Externally Positioned Ligand-Coated Nanopatches Facilitate the Adhesion-Dependent Regenerative Polarization of Host Macrophages

Macrophages can associate with extracellular matrix (ECM) demonstrating nanosequenced cell-adhesive RGD ligand. In this study, we devised barcoded materials composed of RGD-coated gold and RGD-absent iron nanopatches to show various frequencies and position of RGD-coated nanopatches with similar areas of iron and RGD-gold nanopatches that maintain macroscale and nanoscale RGD density invariant. Iron patches were used for substrate coupling. Both large (low frequency) and externally positioned RGD-coated nanopatches stimulated robust attachment in macrophages, compared with small (high frequency) and internally positioned RGD-coated nanopatches, respectively, which mediate their regenerative/anti-inflammatory M2 polarization. The nanobarcodes exhibited stability in vivo. We shed light into designing ligand-engineered nanostructures in an external position to facilitate host cell attachment, thereby eliciting regenerative host responses.

In Situ Magnetic Control of Macroscale Nanoligand Density Regulates the Adhesion and Differentiation of Stem Cells

Developing materials with remote controllability of macroscale ligand presentation can mimic extracellular matrix (ECM) remodeling to regulate cellular adhesion in vivo. Herein, we designed charged mobile nanoligands with superparamagnetic nanomaterials amine-functionalized and conjugated with polyethylene glycol linker and negatively charged RGD ligand. We coupled negatively a charged nanoligand to a positively charged substrate by optimizing electrostatic interactions to allow reversible planar movement. We demonstrate the imaging of both macroscale and in situ nanoscale nanoligand movement by magnetically attracting charged nanoligand to manipulate macroscale ligand density. We show that in situ magnetic control of attracting charged nanoligand facilitates stem cell adhesion, both in vitro and in vivo, with reversible control. Furthermore, we unravel that in situ magnetic attraction of charged nanoligand stimulates mechanosensing-mediated differentiation of stem cells. This remote controllability of ECM-mimicking reversible ligand variations is promising for regulating diverse reparative cellular processes in vivo.

Rationally Designed Polymer Conjugate for Tumor-Specific Amplification of Oxidative Stress and Boosting Antitumor Immunity

The crosstalk between tumor and stroma cells is a central scenario in the tumor microenvironment (TME). While the predominant effect of tumor cells on immune cells is establishing an immunosuppressive context, tumor cell death at certain conditions will boost antitumor immunity. Herein, we report a rationally designed tumor specific enhanced oxidative stress polymer conjugate (TSEOP) for boosting antitumor immunity. The TSEOP is prepared by Passerini reaction between cinnamaldehyde (CA), 4-formylbenzeneboronic acid pinacol ester, and 5-isocyanopent-1-yne, followed by azide-alkyne click reaction with poly(l-glutamic acid)-graft-poly(ethylene glycol) monomethyl ether (PLG-g-mPEG). Under tumor stimuli condition, CA and quinone methide (QM) are quickly generated, which cooperatively induce strong oxidative stress, immunogenic tumor cell death (ICD), and activation of antigen presenting cells. In vivo studies show that the TSEOP treatment boosts tumor-specific antitumor immunity and eradicates both murine colorectal and breast tumors. This study should be inspirational for designing polymers as immunotherapeutics in cancer therapy.