Selenopeptide Nanomedicine Activates Natural Killer Cells for Enhanced Tumor Chemoimmunotherapy

Intelligent Biomaterialomics: Molecular Design, Manufacturing, and Biomedical Applications

Materialomics integrates experiment, theory, and computation in a high-throughput manner, and has changed the paradigm for the research and development of new functional materials. Recently, with the rapid development of high-throughput characterization and machine-learning technologies, the establishment of biomaterialomics that tackles complex physiological behaviors has become accessible. Breakthroughs in the clinical translation of nanoparticle-based therapeutics and vaccines have been observed. Herein, recent advances in biomaterials, including polymers, lipid-like materials, and peptides/proteins, discovered through high-throughput screening or machine learning-assisted methods, are summarized. The molecular design of structure-diversified libraries; high-throughput characterization, screening, and preparation; and, their applications in drug delivery and clinical translation are discussed in detail. Furthermore, the prospects and main challenges in future biomaterialomics and high-throughput screening development are highlighted.

Nanomedicine Targeting Myeloid-Derived Suppressor Cells Enhances Anti-Tumor Immunity

Cancer immunotherapy, a field within immunology that aims to enhance the host's anti-cancer immune response, frequently encounters challenges associated with suboptimal response rates. The presence of myeloid-derived suppressor cells (MDSCs), crucial constituents of the tumor microenvironment (TME), exacerbates this issue by fostering immunosuppression and impeding T cell differentiation and maturation. Consequently, targeting MDSCs has emerged as crucial for immunotherapy aimed at enhancing anti-tumor responses. The development of nanomedicines specifically designed to target MDSCs aims to improve the effectiveness of immunotherapy by transforming immunosuppressive tumors into ones more responsive to immune intervention. This review provides a detailed overview of MDSCs in the TME and current strategies targeting these cells. Also the benefits of nanoparticle-assisted drug delivery systems, including design flexibility, efficient drug loading, and protection against enzymatic degradation, are highlighted. It summarizes advances in nanomedicine targeting MDSCs, covering enhanced treatment efficacy, safety, and modulation of the TME, laying the groundwork for more potent cancer immunotherapy.

X-ray Activated Nanoprodrug for Visualization of Cortical Microvascular Alterations and NIR-II Image-Guided Chemo-Radiotherapy of Glioblastoma

The permeability of the highly selective blood-brain barrier (BBB) to anticancer drugs and the difficulties in defining deep tumor boundaries often reduce the effectiveness of glioma treatment. Thus, exploring the combination of multiple treatment modalities under the guidance of second-generation near-infrared (NIR-II) window fluorescence (FL) imaging is considered a strategic approach in glioma theranostics. Herein, a hybrid X-ray-activated nanoprodrug was developed to precisely visualize the structural features of glioma microvasculature and delineate the boundary of glioma for synergistic chemo-radiotherapy. The nanoprodrug comprised down-converted nanoparticle (DCNP) coated with X-ray sensitive poly(Se-Se/DOX-co-acrylic acid) and targeted Angiopep-2 peptide (DCNP@P(Se-DOX)@ANG). Because of its ultrasmall size and the presence of DOX, the nanoprodrug could easily cross BBB to precisely monitor and localize glioblastoma via intracranial NIR-II FL imaging and synergistically administer antiglioblastoma chemo-radiotherapy through specific X-ray-induced DOX release and radiosensitization. This study provides a novel and effective strategy for glioblastoma imaging and chemo-radiotherapy.

NK cell-based tumor immunotherapy

Natural killer (NK) cells display a unique inherent ability to identify and eliminate virus-infected cells and tumor cells. They are particularly powerful for elimination of hematological cancers, and have attracted considerable interests for therapy of solid tumors. However, the treatment of solid tumors with NK cells are less effective, which can be attributed to the very complicated immunosuppressive microenvironment that may lead to the inactivation, insufficient expansion, short life, and the poor tumor infiltration of NK cells. Fortunately, the development of advanced nanotechnology has provided potential solutions to these issues, and could improve the immunotherapy efficacy of NK cells. In this review, we summarize the activation and inhibition mechanisms of NK cells in solid tumors, and the recent advances in NK cell-based tumor immunotherapy boosted by diverse nanomaterials. We also propose the challenges and opportunities for the clinical application of NK cell-based tumor immunotherapy.

Controllable Gold Nanocluster-Emulsion Interface for Direct Cell Penetration and Photothermal Killing

In the view of their ability to be uptaken by cells, colloidal particles can exert diverse physiological effects and are promising vehicles for the intracellular delivery of biologically active substances. Given that the modulation of biomaterial interfaces greatly facilitates the prediction and control of the corresponding cellular responses, the interfacial behavior of hydrophobic dye-modified gold (Au) nanoclusters (Au NCs) is rationally designed to develop Au NC-containing emulsions and control their biointerfacial interactions with cell membranes. The observed biological performance is indicative of a physical penetration mechanism. The amphiphilic Au NCs decrease the interfacial energy of two immiscible liquids and hinder droplet coalescence to facilitate the formation of emulsions thermodynamically stabilized by dipole-dipole and hydrophobic interactions. Moreover, the amphiphilic Au NCs are localized on the emulsion droplet surface and form segregated interfacial microdomains that adapt to the membrane structure and facilitate the traverse of the emulsions across the cell membrane via direct penetration. Fast penetration coupled with excellent photophysical performance endows the emulsions with multifluorescence tracing and efficient photothermal killing capabilities. The successful change of the interaction mode between NCs and biological objects and the provision of a universal formulation to modulate biointerfacial interactions are expected to inspire new bioapplications.

Multistage Self-Assembled Nanomaterials for Cancer Immunotherapy

Advances in nanotechnology have brought innovations to cancer therapy. Nanoparticle-based anticancer drugs have achieved great success from bench to bedside. However, insufficient therapy efficacy due to various physiological barriers in the body remains a key challenge. To overcome these biological barriers and improve the therapeutic efficacy of cancers, multistage self-assembled nanomaterials with advantages of stimuli-responsiveness, programmable delivery, and immune modulations provide great opportunities. In this review, we describe the typical biological barriers for nanomedicines, discuss the recent achievements of multistage self-assembled nanomaterials for stimuli-responsive drug delivery, highlighting the programmable delivery nanomaterials, in situ transformable self-assembled nanomaterials, and immune-reprogramming nanomaterials. Ultimately, we perspective the future opportunities and challenges of multistage self-assembled nanomaterials for cancer immunotherapy.

Current research trends of nanomedicines

Owing to the inherent shortcomings of traditional therapeutic drugs in terms of inadequate therapeutic efficacy and toxicity in clinical treatment, nanomedicine designs have received widespread attention with significantly improved efficacy and reduced non-target side effects. Nanomedicines hold tremendous theranostic potential for treating, monitoring, diagnosing, and controlling various diseases and are attracting an unfathomable amount of input of research resources. Against the backdrop of an exponentially growing number of publications, it is imperative to help the audience get a panorama image of the research activities in the field of nanomedicines. Herein, this review elaborates on the development trends of nanomedicines, emerging nanocarriers, in vivo fate and safety of nanomedicines, and their extensive applications. Moreover, the potential challenges and the obstacles hindering the clinical translation of nanomedicines are also discussed. The elaboration on various aspects of the research trends of nanomedicines may help enlighten the readers and set the route for future endeavors.

Programming lipopeptide nanotherapeutics for tandem treatment of postsurgical infection and melanoma recurrence

Tumor recurrence and chronic bacterial infection constitute two major criteria in postsurgical intervention for malignant melanoma. One plausible strategy is the equipment of consolidation therapy after surgery, which relies on adjuvants to eliminate the residual tumor cells and inhibit bacterial growth. Until now, a number of proof-of-concept hybrid nanoadjuvants have been proposed to combat tumor recurrence and postsurgical bacterial infection, which may suffer from the potential bio-unsafety or involve complex design and synthesis. The batch-to-batch inconsistencies in drug composition further delay the clinical trials. To circumvent these issues, herein we develop a programmable strategy to generate lipopeptide nanotherapeutics with identical constitution for tandem intervention of postsurgical bacterial infection and cancer recurrence of melanoma. Increasing the number of hydrophobic linoleic acid within lipopeptides has been found to be a simple and practical strategy to improve the therapeutic outcomes for both tumor cells and bacteria. Self-assembled lipopeptide nanotherapeutics with two linoleic acid molecules possesses excellent antitumor activity and antimicrobial function toward both susceptible strains and drug-resistant bacteria. Arising from the incorporation of unsaturated linoleic acid, the unavoidable hemolysis of cationic peptide drugs was effectively alleviated. In vivo therapeutic abilities of postsurgical infection and tumor recurrence were investigated in BALB/c nude mice bearing a B16-F10 tumor model, with an incomplete surgical resection and in situ infection by methicillin-resistant Staphylococcus aureus (MRSA). Self-assembled lipopeptide nanotherapeutics could effectively inhibit cancer cell growth and bacterial infection, as well as promote wound healing. The easily scalable large-scale production, broad-spectrum antitumor and antibacterial bioactivities as well as fixed component endows lipopeptide nanotherapeutics as promising adjuvants for clinically postsurgical therapy of melanoma.

Advancement and Applications of Nanotherapy for Cancer Immune Microenvironment

Cancer treatment has evolved rapidly due to major advances in tumor immunity research. However, due to the complexity, heterogeneity, and immunosuppressive microenvironment of tumors, the overall efficacy of immunotherapy is only 20%. In recent years, nanoparticles have attracted more attention in the field of cancer immunotherapy because of their remarkable advantages in biocompatibility, precise targeting, and controlled drug delivery. However, the clinical application of nanomedicine also faces many problems concerning biological safety, and the synergistic mechanism of nano-drugs with immunity remains to be elucidated. Our study summarizes the functional characteristics and regulatory mechanisms of nanoparticles in the cancer immune microenvironment and how nanoparticles activate and long-term stimulate innate immunity and adaptive immunity. Finally, the current problems and future development trends regarding the application of nanoparticles are fully discussed and prospected to promote the transformation and application of nanomedicine used in cancer treatment.

Research progress in leveraging biomaterials for enhancing NK cell immunotherapy

NK cell immunotherapy is a promising antitumor therapeutic modality after the development of T cell immunotherapy. Structural modification of NK cells with biomaterials may provide a precise, efficient, and low-cost strategy to enhance NK cell immunotherapy. The biomaterial modification of NK cells can be divided into two strategies: surface engineering with biomaterials and intracellular modification. The surface engineering strategies include hydrophobic interaction of lipids, receptor-ligand interaction between membrane proteins, covalent binding to amino acid residues, click reaction and electrostatic interaction. The intracellular modification strategies are based on manipulation by nanotechnology using membranous materials from various sources of NK cells (such as exosome, vesicle and cytomembranes). Finally, the biomaterials-based strategies regulate the recruitment, recognition and cytotoxicity of NK cells in the solid tumor site in situ to boost the activity of NK cells in the tumor. This article reviews the recent research progress in enhancing NK cell therapy based on biomaterial modification, to provide a reference for further researches on engineering NK cell therapy with biomaterials.

A Nanotherapeutic Strategy to Reverse NK Cell Exhaustion

As a specialized immune effector cell, natural killer (NK) cells play a very important role in immunotherapy, but tumor immunosuppression caused by abnormal expression of cancer cells seriously weakens its therapeutic effect and leads to exhaustion. Here, self-assembled selenium-containing nanoparticles (NPs) composed of cetuximab, C5SeSeC5, and inhibitor LY345899 are developed to reverse NK cell exhaustion. The obtained NPs can target epidermal growth factor receptor on the surface of cancer cells and locate it in mitochondria. The released LY345899 can inhibit the activity of methylene tetrahydrofolate dehydrogenase 2 and produce excessive reactive oxygen species, leading to the formation of seleninic acid, further reducing the expression of human leukocyte antigen E , which is responsible for the NKG2A-related NK cell inhibition. As a result, the enhanced NK-cell-mediated immunotherapy in conjunction with the cetuximab-mediated antibody-dependent cell-mediated cytotoxicity effect can not only effectively inhibit the growth of xenograft tumors, but also significantly suppress the growth of untreated distant tumors via the abscopal effect. This work, the combination of seleninic acid, LY345899, and cetuximab, provides a new strategy for reversing NK cell exhaustion and has great potential for use in the treatment of metastatic tumors.

Transformable Neuropeptide Prodrug with Tumor Microenvironment Responsiveness for Tumor Growth and Metastasis Inhibition of Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) has the worst prognosis among all breast cancer subtypes due to lack of specific target sites and effective treatments. Herein, a transformable prodrug (DOX-P18) based on neuropeptide Y analogue with tumor microenvironment responsiveness is developed for TNBC treatment. The prodrug DOX-P18 can achieve reversible morphological transformation between monomers and nanoparticles through the manipulation of protonation degree in different environments. It can self-assemble into nanoparticles to enhance the circulation stability and drug delivery efficiency in the physiological environment while transforming from nanoparticles to monomers and being endocytosed into the breast cancer cells in the acidic tumor microenvironment. Further, the DOX-P18 can precisely be enriched in the mitochondria, and efficiently activated by matrix metalloproteinases. Then, the cytotoxic fragment (DOX-P3) can subsequently be diffused into the nucleus, generating a sustained cell toxicity effect. In the meanwhile, the hydrolysate residue P15 can assemble into nanofibers to construct nest-like barriers for the metastasis inhibition of cancer cells. After intravenous injection, the transformable prodrug DOX-P18 demonstrated superior tumor growth and metastasis suppression with much better biocompatibility and improved biodistribution compared to free DOX. As a novel tumor microenvironment-responsive transformable prodrug with diversified biological functions, DOX-P18 shows great potential in smart chemotherapeutics discovery for TBNC.

Electrochemical Selenylation of Sulfoxonium Ylides for the Synthesis of gem-Diselenides as Antimicrobials against Fungi

Organoselenium compounds are important scaffolds in pharmaceutical molecules. Herein, we report metal-free, electrochemical, highly chemo- and regioselective synthesis of gem-diselenides through the coupling of α-keto sulfoxonium ylides with diselenides. The versatility of the electrochemical manifold enabled the selenylation with ample scope and broad functional group tolerance, as well as setting the stage for modification of complex bioactive molecules. Detailed mechanistic studies revealed that the key C-Se bond was constructed using n-Bu₄NI as an electrolyte and catalyst through the electrosynthetic protocol. Finally, the desired α-keto gem-diselenides showed excellent antimicrobial activity against Candida albicans, which can be identified as the lead compounds for further exploration.

Visible Light-Responsive Selenium Nanoparticles Combined with Sonodynamic Therapy to Promote Wound Healing

In this paper, we synthesized selenium nanoparticles (SeNPs) that could be effectively excited by pure yellow light (YL) source to enhance antibacterial ability. Meanwhile, YL could also play the role of anti-inflammatory and promote wound healing. In addition, in order to overcome the problem of low penetration depth of photodynamic therapy (PDT), SeNPs were encapsulated with polyethylenimine (PEI), then modified with the sound sensitive agent indocyanine green (ICG), realizing the combined photoacoustic therapy to promote the healing of wounds infected by drug-resistant bacteria. The antibacterial efficiency of methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli) reached more than 99% in in vitro and in vivo experiments within 10 min, which could safely and quickly kill drug-resistant bacteria to repair and heal wounds.

Confinement of Assemblies of Peptides by Chemical Reactions in Living Cells

The self-assembly of peptides plays an important role in optics, catalysis, medicine, and disease treatment. In recent years, peptide-based materials have exhibited great potential for cancer therapy and disease imaging due to their excellent biocompatibility, structural tenability, and ease of functionality. Peptides could self-assemble into diverse nanostructures in vivo triggered by endogenous stimuli, which initiated chemical reactions and self-assembled to achieve desired biological functions in the tumor microenvironment. This concept introduces the utilization of endogenous triggers to construct functional nanostructures in vivo and their corresponding biological applications. After briefly discussing the representative example of chemical reactions induced self-assembly of peptides in the living system, we describe the several stimuli triggered self-assembly for constructing therapeutic assemblies and serving as an imaging probe. Finally, we give a brief outlook to discuss the future direction of this exciting new field.

Metabolic Reprogramming of NK Cells by Black Phosphorus Quantum Dots Potentiates Cancer Immunotherapy

Low persistence, metabolic dysfunction in microenvironment, and tumor-derived immunosuppression of Natural killer (NK) cells in patients are greatly limited the successful clinical application of NK cell-based cancer immunotherapy. Interestingly, herein that human serum albumin-encapsulated black phosphorus quantum dots (BPQDs@HSA) can effectively augment antitumor efficacy of clinical patients-derived NK cell immunotherapy is found. As the donor of phosphate group, BPQDs@HSA binds with the protein of phosphatidylinositol 4-phosphate 5-kinase type-1 gamma (PIP5K1A) and activates the downstream PI3K-Akt and mTOR signaling pathways to reprogram cell metabolism of glycolysis and further promote the oxidative phosphorylation, sequentially maintains the cell viability and immunity of NK cells. And multiomics analysis is therefore conducted to reveal the underlying immunoregulation mechanisms, and that BPQDs@HSA can interact with the Toll-like receptor (TLR) on the NK cell surface and increase the expression level of mTOR, and thus activate downstream NF-κB signalling pathways to regulate cytokine secretion and enhance immune tumoricidal is found. BPQDs@HSA can also enhance immune surveillance, relieve immune suppression, and inhibit tumor immune escape. Collectively, this study not only demonstrates a successful strategy for nanomedicine-potentiated immune-cancer therapy, but also sheds light on the understanding of interface between nanomedicine and immune cells activation.

Smart Nanoparticle-Based Platforms for Regulating Tumor Microenvironment and Cancer Immunotherapy

Tumor development and metastasis are closely related to the tumor microenvironment (TME). Recently, several studies indicate that modulating TME can enhance cancer immunotherapy. Among various approaches to modulating TME, nanoparticles (NPs) with unique inherent advantages and smart modified characteristics are promising candidates in delivering drugs to cancer cells, amplifying the therapeutic effects, and leading to a cascade of immune responses. In this review, several smart NP-based platforms are briefly introduced, such as responsive NPs, targeting NPs, and the composition of TME, including dendritic cells, macrophages, fibroblasts, endothelial cells, myeloid-derived suppressor cells, and regulatory T cells. Moreover, the recent applications of smart NP-based platforms in regulating TME and cancer immunotherapy are briefly introduced. Last, the advantages and disadvantages of these smart NP-based platforms in potential clinical translation are discussed.

Multifunctional Self-Assembled Peptide Hydrogels for Biomedical Applications

Self-assembly is a growth mechanism in nature to apply local interactions forming a minimum energy structure. Currently, self-assembled materials are considered for biomedical applications due to their pleasant features, including scalability, versatility, simplicity, and inexpensiveness. Self-assembled peptides can be applied to design and fabricate different structures, such as micelles, hydrogels, and vesicles, by diverse physical interactions between specific building blocks. Among them, bioactivity, biocompatibility, and biodegradability of peptide hydrogels have introduced them as versatile platforms in biomedical applications, such as drug delivery, tissue engineering, biosensing, and treating different diseases. Moreover, peptides are capable of mimicking the microenvironment of natural tissues and responding to internal and external stimuli for triggered drug release. In the current review, the unique characteristics of peptide hydrogels and recent advances in their design, fabrication, as well as chemical, physical, and biological properties are presented. Additionally, recent developments of these biomaterials are discussed with a particular focus on their biomedical applications in targeted drug delivery and gene delivery, stem cell therapy, cancer therapy and immune regulation, bioimaging, and regenerative medicine.

pH-Responsive Selenium Nanoplatform for Highly Efficient Cancer Starvation Therapy by Atorvastatin Delivery

Recently, starvation-inducing nutrient deprivation has been regarded as a promising strategy for tumor suppression. As a first-line lipid-lowering drug, atorvastatin (ATV) significantly reduces caloric intake, suggesting its potential in starvation therapy for suppressing tumors. Accordingly, we developed a novel starvation therapy agent (HA-Se-ATV) in this study to suppress tumor growth by using hyaluronic acid (HA)-conjugated chitosan polymer-coated nano-selenium (Se) for loading ATV. HA-Se-ATV targets cancer cells, following which it effectively accumulates in the tumor tissue. The HA-Se-ATV nanoplatform was then activated by inducing a weakly acidic tumor microenvironment and subsequently releasing ATV. ATV and Se synergistically downregulate the levels of cellular adenosine triphosphate while inhibiting the expression of thioredoxin reductase 1. Consequently, the starvation-stress reaction of cancer cells is significantly elevated, leading to cancer cell death. Furthermore, the in vivo results indicate that HA-Se-ATV effectively suppresses tumor growth with a low level of toxicity, demonstrating its great potential for clinical translation.

Nucleolin recognizing silica nanoparticles inhibit cell proliferation by activating the Bax/Bcl-2/caspase-3 signalling pathway to induce apoptosis in liver cancer

Multifunctional nanocarrier platforms have shown great potential for the diagnosis and treatment of liver cancer. Here, a novel nucleolin-responsive nanoparticle platform was constructed for the concurrent detection of nucleolin and treatment of liver cancer. The incorporation of AS1411 aptamer, icaritin (ICT) and FITC into mesoporous silica nanoparticles, labelled as Atp-MSN (ICT@FITC) NPs, was the key to offer functionalities. The specific combination of the target nucleolin and AS1411 aptamer caused AS1411 to separate from mesoporous silica nanoparticles surface, allowing FITC and ICT to be released. Subsequently, nucleolin could be detected by monitoring the fluorescence intensity. In addition, Atp-MSN (ICT@FITC) NPs can not only inhibit cell proliferation but also improve the level of ROS while activating the Bax/Bcl-2/caspase-3 signalling pathway to induce apoptosis in vitro and in vivo. Moreover, our results demonstrated that Atp-MSN (ICT@FITC) NPs had low toxicity and could induce CD3⁺ T-cell infiltration. As a result, Atp-MSN (ICT@FITC) NPs may provide a reliable and secure platform for the simultaneous identification and treatment of liver cancer.

Nanoparticle Enhancement of Natural Killer (NK) Cell-Based Immunotherapy

Simple Summary

Natural killer cells are a part of the native immune response to cancer. NK cell-based immunotherapies are an emerging strategy to kill tumor cells. This paper reviews the role of NK cells, their mechanism of action for killing tumor cells, and the receptors which could serve as potential targets for signaling. In this review, the role of nanoparticles in NK cell activation and increased cytotoxicity of NK cells against cancer are highlighted.

Abstract

Natural killer (NK) cells are one of the first lines of defense against infections and malignancies. NK cell-based immunotherapies are emerging as an alternative to T cell-based immunotherapies. Preclinical and clinical studies of NK cell-based immunotherapies have given promising results in the past few decades for hematologic malignancies. Despite these achievements, NK cell-based immunotherapies have limitations, such as limited performance/low therapeutic efficiency in solid tumors, the short lifespan of NK cells, limited specificity of adoptive transfer and genetic modification, NK cell rejection by the patient’s immune system, insignificant infiltration of NK cells into the tumor microenvironment (TME), and the expensive nature of the treatment. Nanotechnology could potentially assist with the activation, proliferation, near-real time imaging, and enhancement of NK cell cytotoxic activity by guiding their function, analyzing their performance in near-real time, and improving immunotherapeutic efficiency. This paper reviews the role of NK cells, their mechanism of action in killing tumor cells, and the receptors which could serve as potential targets for signaling. Specifically, we have reviewed five different areas of nanotechnology that could enhance immunotherapy efficiency: nanoparticle-assisted immunomodulation to enhance NK cell activity, nanoparticles enhancing homing of NK cells, nanoparticle delivery of RNAi to enhance NK cell activity, genetic modulation of NK cells based on nanoparticles, and nanoparticle activation of NKG2D, which is the master regulator of all NK cell responses.

Nanomaterials for Natural Killer Cell-Based Immunoimaging and Immunotherapies in Cancer

Natural killer (NK) cells are an important component of the tumor immunosurveillance; activated NK cells can recognize and directly lyse tumor cells eliciting a potent antitumor immune response. Due to their intrinsic ability to unleash cytotoxicity against tumor cells, NK cell-based adoptive cell therapies have gained rapid clinical significance, and many clinical trials are ongoing. However, priming and activating NK cells, infiltration of activated NK cells in the immunosuppressive tumor microenvironment, and tracking the infiltrated NK cells in the tumors remain a critical challenge. To address these challenges, NK cells have been successfully interfaced with nanomaterials where the morphology, composition, and surface characteristics of nanoparticles (NPs) were leveraged to enable longitudinal tracking of NK cells in tumors or deliver therapeutics to prime NK cells. Distinct from other published reviews, in this tutorial review, we summarize the recent findings in the past decade where NPs were used to label NK cells for immunoimaging or deliver treatment to activate NK cells and induce long-term immunity against tumors. We discuss the NP properties that are key to surmounting the current challenges in NK cells and the different strategies employed to advance NK cells-based diagnostics and therapeutics. We conclude the review with an outlook on future directions in NP-NK cell hybrid interfaces, and overall clinical impact and patient response to such interfaces that need to be addressed to enable their clinical translation.

Self-Assembly of Small Organic Molecules into Luminophores for Cancer Theranostic Applications

Self-assembled biomaterials have been widely explored for real-time fluorescence imaging, imaging-guided surgery, and targeted therapy for tumors, etc. In particular, small molecule-based self-assembly has been established as a reliable strategy for cancer theranostics due to the merits of small-sized molecules, multiple functions, and ease of synthesis and modification. In this review, we first briefly introduce the supramolecular chemistry of small organic molecules in cancer theranostics. Then, we summarize and discuss advanced small molecule-based self-assembly for cancer theranostics based on three types, including peptides, amphiphilic molecules, and aggregation-induced emission luminogens. Finally, we conclude with a perspective on future developments of small molecule-based self-assembled biomaterials integrating diagnosis and therapy for biomedical applications. These applications highlight the opportunities arising from the rational design of small organic molecules with self-assembly properties for precision medicine.

Aptamer-siRNA chimera and gold nanoparticle modified collagen membrane for the treatment of malignant pleural effusion

Malignant pleural effusion is one of the most common complications of advanced lung cancer and there is no effective clinical treatment at present. Here, we constructed an aptamer-siRNA chimeras/PEI/PEG/gold nanoparticle (AuNP)/collagen membrane that can progressively activate T cells by layer by layer assembly. Electron microscope showed this collagen membrane could be divided into 10 layers with a total thickness of 50–80μm, and AuNPs could be observed. Aptamer-siRNA chimeras could bind specifically to OX40⁺ cells and silencing programmed death receptor-1 (PD-1) gene. In vitro experiments demonstrated that chimeras/PEI/PEG/AuNPs gradually activated T cells to continuously kill lung adenocarcinoma cells in malignant pleural effusion. Animal experiments showed that chimeras/PEI/PEG/AuNP/collagen membrane effectively treated malignant pleural effusion. Compared with PD-1 inhibitor group, the number of cancer cells, ki-67 proliferation index and CD44 expression in the pleural effusion was significantly decreased and the lymphocyte/cancer cell ratio was significantly increased in the chimeras/AuNP-CM group. Flow cytometry showed that compared with PD-1 inhibitor group, T cell number in the chimeras/AuNP-CM group was significantly increased, while the proportion of PD-1⁺ T cells was markedly decreased. In conclusion, we constructed an chimeras/PEI/PEG/AuNP/collagen membrane, which was more effective in the treatment of malignant pleural effusion, and had less side effects than PD-1 inhibitors.

When Natural Compounds Meet Nanotechnology: Nature-Inspired Nanomedicines for Cancer Immunotherapy

Recent significant strides of natural compounds in immunomodulation have highlighted their great potential against cancer. Despite many attempts being made for cancer immunotherapy, the biomedical application of natural compounds encounters a bottleneck because of their unclear mechanisms, low solubility and bioavailability, and limited efficacy. Herein, we summarize the immune regulatory mechanisms of different natural compounds at each step of the cancer-immunity cycle and highlight their anti-tumor potential and current limitations. We then propose and present various drug delivery strategies based on nanotechnology, including traditional nanoparticles (NPs)-based delivery strategies (lipid-based NPs, micelles, and polysaccharide/peptide/protein-based NPs) and novel delivery strategies (cell-derived NPs and carrier-free NPs), thus providing solutions to break through existing bottlenecks. Furthermore, representative applications of nature-inspired nanomedicines are also emphasized in detail with the advantages and disadvantages discussed. Finally, the challenges and prospects of natural compounds for cancer immunotherapy are provided, hopefully, to facilitate their far-reaching development toward clinical translation.

Immunomodulatory roles of selenium nanoparticles: Novel arts for potential immunotherapy strategy development

Current chemotherapy strategies used in clinic appear with lots of disadvantages due to the low targeting effects of drugs and strong side effects, which significantly restricts the drug potency, causes multiple dysfunctions in the body, and even drives the emergence of diseases. Immunotherapy has been proved to boost the body’s innate and adaptive defenses for more effective disease control and treatment. As a trace element, selenium plays vital roles in human health by regulating the antioxidant defense, enzyme activity, and immune response through various specific pathways. Profiting from novel nanotechnology, selenium nanoparticles have been widely developed to reveal great potential in anticancer, antibacterial, and anti-inflammation treatments. More interestingly, increasing evidence has also shown that functional selenium nanoparticles can be applied for potential immunotherapy, which would achieve more effective treatment efficiency as adjunctive therapy strategies for the current chemotherapy. By directly interacting with innate immune cells, such as macrophages, dendritic cells, and natural killer cells, selenium nanoparticles can regulate innate immunity to intervene disease developments, which were reported to boost the anticancer, anti-infection, and anti-inflammation treatments. Moreover, selenium nanoparticles can also activate and recover different T cells for adaptive immunity regulations to enhance their cytotoxic to combat cancer cells, indicating the potential of selenium nanoparticles for potential immunotherapy strategy development. Here, aiming to enhance our understanding of the potential immunotherapy strategy development based on Se NPs, this review will summarize the immunological regulation effects of selenium nanoparticles and the application of selenium nanoparticle-based immunotherapy strategies. Furthermore, we will discuss the advancing perspective of selenium nanoparticle-based potential immunotherapy as a kind of novel adjunctive therapy to enhance the efficiency of current chemotherapies and also introduce the current obstacles for the development of selenium nanoparticles for potential immunotherapy strategy development. This work is expected to promote the future research on selenium nanoparticle-assisted immunotherapy and finally benefit the more effective disease treatments against the threatening cancer and infectious and chronic diseases.

Diselenide–yne chemistry for selenium-containing linear polymer modification

Selenium-containing brush polymers with diverse functional segments were easily prepared through diselenide–yne chemistry.