Direct Presentation of Tumor-Associated Antigens to Induce Adaptive Immunity by Personalized Dendritic Cell-Mimicking Nanovaccines

Progress of extracellular vesicles-based system for tumor therapy

The increasing number of new cancer cases and cancer-related deaths worldwide highlights the urgent need to develop novel anti-tumor treatment methods to alleviate the current challenging situation. Nearly all organisms are capable of secreting extracellular vesicles (EVs), and these nano-scale EVs carrying biological molecules play an important role in intercellular communication, further affecting various physiological and pathological processes. Notably, EVs from different sources have differences in their characteristics and functions. Consequently, diverse EVs have been utilized as drug or vaccine delivery carriers for improving anti-tumor treatment due to their good safety, ease of modification and unique properties, and achieved satisfactory results. Meanwhile, the clinical trials of EV-based platform for tumor therapy are also continuously being conducted. Therefore, in this review, we summarize the recent research progress of EV-based tumor treatment methods, including the introduction of main sources and unique functions of EVs, the application of EVs in tumor treatment as well as their prospects and challenges. Additionally, considering the unique advantages of artificial EVs over natural EVs, we also highlighted their characteristics and applications in tumor treatments. We believe that this review will help researchers develop novel EV-based anti-tumor platforms through a bottom-up design and accelerate the development in this field.

Fe-Doped Carbon Dots-Incorporated In Situ Hydrogel for Near Infrared-Triggered Cascading Photothermal/Thermodynamic Therapy to Boost Cancer Immunity Cycle

Photothermal therapy-triggered whole-tumor cell antigens release has revolutionized in situ cancer vaccine, but insufficient anticancer immunity cycle activation greatly limits its curative effect. Herein, we designed an NIR-triggered cascading in situ vaccine (FCDs-A/C@HGs) by incorporating the Fe-doped carbon dots (FCDs), azo-initiator (AIPH), and immune adjuvant (cyclophosphamide) into the thermosensitive hydrogel. Due to iron doping, the as-prepared FCDs exhibited high photothermal conversion performance and favorable MR imaging capability. Upon intratumoral injection, local hyperthermia mediated by FCDs-A/C@HGs and the subsequent generation of alkyl radicals from AIPH synergistically induced immunogenic cell death in tumor cells. Remarkably, the FCDs-A/C@HGs elicited strong anticancer immune activation by inhibiting regulatory T cells and promoting dendritic cell maturation, thereby enhancing differentiation of cytotoxic CD8+ T cells and memory T cells. This study presents an effective therapeutic platform for in situ tumor suppression and sustained activation of the anticancer immunity cycle.

Cancer Nanovaccines: Mechanisms, Design Principles, and Clinical Translation

Cancer immunotherapy has transformed the landscape of oncological treatment by employing various strategies to teach the immune system to eliminate tumors. Among these, cancer nanovaccines are an emerging strategy that utilizes nanotechnology to enhance immune activation in response to tumor antigens. This review addresses the principles behind the different technologies in this field aimed at generating a robust and effective immune response. The diversity of strategies adopted for the design of nanovaccines is discussed, including the types of active agents, nanocarriers, their functionalizations, and the incorporation of adjuvants. Furthermore, strategies to optimize nanoparticle formulations to enhance the antigen presentation, target immune cells, and organs and promote strong and durable antitumor responses are explored. Finally, we analyze the current state of clinical application, highlighting ongoing clinical trials and the future potential of cancer nanovaccines. The insights presented in this review aim to guide future research and development efforts in the field, contributing to the advancement of more effective and targeted nanovaccines in the fight against cancer.

Advances in Therapeutic Cancer Vaccines, Their Obstacles, and Prospects Toward Tumor Immunotherapy

Over the past few decades, cancer immunotherapy has experienced a significant revolution due to the advancements in immune checkpoint inhibitors (ICIs) and adoptive cell therapies (ACTs), along with their regulatory approvals. In recent times, there has been hope in the effectiveness of cancer vaccines for therapy as they have been able to stimulate de novo T-cell reactions against tumor antigens. These tumor antigens include both tumor-associated antigen (TAA) and tumor-specific antigen (TSA). Nevertheless, the constant quest to fully achieve these abilities persists. Therefore, this review offers a broad perspective on the existing status of cancer immunizations. Cancer vaccine design has been revolutionized due to the advancements made in antigen selection, the development of antigen delivery systems, and a deeper understanding of the strategic intricacies involved in effective antigen presentation. In addition, this review addresses the present condition of clinical tests and deliberates on their approaches, with a particular emphasis on the immunogenicity specific to tumors and the evaluation of effectiveness against tumors. Nevertheless, the ongoing clinical endeavors to create cancer vaccines have failed to produce remarkable clinical results as a result of substantial obstacles, such as the suppression of the tumor immune microenvironment, the identification of suitable candidates, the assessment of immune responses, and the acceleration of vaccine production. Hence, there are possibilities for the industry to overcome challenges and enhance patient results in the coming years. This can be achieved by recognizing the intricate nature of clinical issues and continuously working toward surpassing existing limitations.

A precision intelligent nanomissile for inhibiting tumor metastasis, boosting energy deprivation and immunotherapy

The epithelial-mesenchymal transition (EMT), tumor stroma and local metabolic alterations cooperate to establish a unique tumor microenvironment (TME) that fosters tumor progression and metastasis. To tackle this challenge, a precision intelligent nanomissile named HA@AT-Pd has been designed for dual-pronged cancer-associated fibroblast (CAF) transformation and tumor cell elimination. It is observed that HA@AT-Pd inhibits the production of cancer stem cells (CSCs) by blocking the TGF-β/Smad signaling pathway-mediated EMT and reversing activated CAFs to quiescence. Notably, HA@AT-Pd induces energy depletion in breast cancer cells through simultaneously suppressing cellular oxidative phosphorylation and glycolysis. The inhibition of glycolysis results in reduced lactic acid production, thereby converting an immunosuppressive TME into an immune-activating environment. Furthermore, the photothermal effect generated by HA@AT-Pd evokes immunogenic cell death, which can further enhance the anti-tumor immune response. Overall, this multifunctional combination strategy unveils potential therapeutic avenues to inhibit tumor progression and metastasis.

Manganese-Driven Plasmid Nanofibers Formed In Situ for Cancer Gene Delivery and Metalloimmunotherapy

While nucleic-acid-based cancer vaccines hold therapeutic potential, their limited immunogenicity remains a challenge due in part to the low efficiency of cytoplasmic delivery caused by lysosomal entrapment. In this work, we found that plasmids encoding both an antigen and a STING agonist protein adjuvant can self-assemble into coordination nanofibers, triggered by manganese ions. We developed a strategy to construct a DNA vaccine, termed MnO2-OVA-CDA-mem, formed by the coencapsulation of manganese dioxide (MnO2), an antigen-expressing plasmid (encoding ovalbumin, OVA), and an adjuvant enzyme-expressing plasmid (encoding STING agonist, CDA) within dendritic cell (DC) membranes. Upon uptake into acidic lysosomes, Mn2+ released from MnO2 triggered the nucleic acids to undergo a morphological change from nanospheres (∼180 nm diameter) to nanofibers (∼1 μm length), resulting in an increase in mechanical strength by about 9-fold and consequently lysosomal membrane disruption. The antigen OVA and adjuvants Mn2+ and CDA in the cytoplasm triggered strong DC activation and antigen-specific CD8+ T cell metalloimmune responses, significantly inhibiting the growth of B16-OVA tumors and inducing long-term immune memory. Altogether, MnO2-OVA-CDA-mem holds potential as a platform for nucleic acid antigen and adjuvant delivery using an in situ self-assembly strategy in a metal-driven, stimulus-responsive, and programmable manner for cancer metalloimmunotherapy.

Acid-Responsive Biocompatible Hydrogel Modulating Tumor DNA Self-Repair Collaborated with Chemotherapy for Boosting STING Pathway-Associated Immunotherapy

In this study, an acid-responsive hydrogel (ODCM@AZD) encapsulating doxorubicin (DOX), Mn2+, and AZD2281 is rationally engineered for synergistic chemo-immunotherapy. Notably, ODCM@AZD can be specifically degraded within the tumor microenvironment to release the loaded therapeutic agents. Specifically, the released DOX kills tumor cells to produce abundant cytoplasmic DNA, while the freed AZD2281 inhibits the DNA repair pathway of tumor cells to enhance the chemotherapeutic effect and promote the accumulation of damaged DNA, which is further aggravated by reactive oxygen species (ROS) generated from the Mn2+-mediated Fenton-like reaction. Not only that, Mn2+ simultaneously increases the sensitivity of cGAS to cytoplasmic DNA to stimulate the cGAS-STING pathway and synergizes with DOX-mediated immunogenic cell death (ICD) to initiate powerful antitumor immune responses. More importantly, the combination of ODCM@AZD with immune checkpoint blockade (ICB) significantly improves systemic tumoricidal immunity and potentiates therapeutic effects on distant and recurrent tumor models, providing a new idea for antitumor chemo-immunotherapy.

Cold Exposure Therapy Enhances Single-Atom Nanozyme-Mediated Cancer Vaccine Therapy

Single-atom nanozymes are highly effective in the preparation of tumor vaccines (TV) due to their superior peroxidase (POD) activity and excellent biocompatibility. However, the immunosuppressive environment within tumors can diminish the efficacy of these vaccines. Cold exposure (CE) therapy, a noninvasive and straightforward antitumor method, not only suppresses tumor metabolism but also ameliorates the immunosuppressive tumor milieu. In this study, we developed personalized TV using copper single-atom nanozyme (Cu SAZ) and enhanced their long-term antitumor efficacy by introducing CE. We initially synthesized the Cu SAZ via high-temperature carbonization, which demonstrated robust POD activity and photothermal characteristics. Upon exposure to 808 nm laser irradiation, the nanozyme generated reactive oxygen species (ROS) and heat, inducing immunogenic cell death in 4T1 breast cancer cells or CT26 colon cancer cells and facilitating TV production. In our in vivo tumor prevention and treatment model, we noted that CE significantly boosted the efficacy of the TV. The primary mechanism involves CE's ability to lower the ratio of myeloid-derived suppressor cells (MDSCs), decrease glucose metabolism in tumor cells, and increase the proportions of CD8+ T cells and memory T cells. Collectively, our findings offer promising avenues for designing innovative TV systems.

CpG-Based Nanovaccines Enhance Ovarian Cancer Immune Response by Gbp2-Mediated Remodeling of Tumor-Associated Macrophages

CpG oligodeoxynucleotides (CpG), as an immunoadjuvant, can facilitate the transformation of tumor-associated macrophages (TAMs)into tumoricidal M1 macrophages. However, the accumulation of free CpG in tumor tissues remains a substantial challenge. To address this, a nanovaccine (PLGA-CpG@ID8-M) is engineered by encapsulating CpG within PLGA using ID8 ovarian cancer cell membranes (ID8-M). This nanovaccine demonstrates remarkable efficacy in reprogramming TAMs in ovarian cancer and significantly extends survival in ID8-bearing mice. Notably, these findings indicate that the nanovaccine can also mitigate chemotherapy-induced immunosuppression by increasing the proportion of M1-like TAMs and reducing the expression of CD47 on tumor cells, thereby achieving a synergistic effect in tumor immunotherapy. Mechanistically, through transcriptome sequencing (RNA-seq), single-cell RNA sequencing (scRNA-seq), and mass spectrometry-based proteomics, it is elucidated that the nanovaccine enhances the expression of Gbp2 and promotes the recruitment of Pin1, which activates the NFκB signaling pathway, leading to the M1 polarization of TAMs. Furthermore, macrophages with elevated Gbp2 expression significantly inhibit tumor growth in both ID8 ovarian cancer and 4T1 breast cancer models. Conversely, targeting Gbp2 diminishes the antitumor efficacy of the nanovaccine in vivo. This study offers an innovative approach to immunotherapy and elucidates a novel mechanism (Gbp2-Pin1-NFκB pathway) for remodeling TAMs.

Manganese Ions Chelated Tumosomes as Autologous Cancer Nanovaccines for Effective Suppression of Postsurgical Tumor Relapse

Autologous cancer vaccines represent a promising strategy to effectively suppress postoperative tumor relapse by eliciting tumor-specific immune responses that highly rely on the efficient internalization and lymph node-targeting delivery of vaccines. Herein, we report an autologous nanovaccine obtained by sequentially incorporating tumor plasma membrane proteins into liposomes, termed tumosomes, and chelating it with metallo-agonist of manganese ions. The yielded Mn-tumosomes with a positively charged surface exhibited significantly enhanced internalization by dendritic cells and enhanced lymph node targeting capacity, the latter of which is indicated by the near-infrared II fluorescence of silver sulfide nanoprobes labeled on their lipid bilayers. As a result, vaccination with Mn-tumosomes elicited potent tumor-specific CD8+ T cells to suppress the growth of challenged allogeneic tumors more effectively than vaccination via bolus injection of plain tumosomes and commercial immune agonists. Furthermore, with the excised tumor mass as the source of whole tumor cell antigens, the as-prepared autologous Mn-tumosomes effectively suppressed the growth of both residual tumor masses and spontaneously formed metastatic tumors, particularly in combination with anti-PD-1 immunotherapy. This work highlights a metal coordination based strategy to fabricate personalized whole-tumor cell nanovaccines with superior lymph node targeting and cellular uptake efficacy for the immunotherapeutic suppression of postoperative tumor relapse.

One-Pot Synthesis of Oxygen Vacancy-Rich Amorphous/Crystalline Heterophase CaWO4 Nanoparticles for Enhanced Radiodynamic-Immunotherapy

Radiodynamic therapy that employs X-rays to trigger localized reactive oxygen species (ROS) generation can tackle the tissue penetration issue of phototherapy. Although calcium tungstate (CaWO4) shows great potential as a radiodynamic agent benefiting from its strong X-ray absorption and the ability to generate electron-hole (e--h+) pairs, slow charge carrier transfer and fast e--h+ recombination greatly limit its ROS-generating performance. Herein, via a one-pot wet-chemical method, oxygen vacancy-rich amorphous/crystalline heterophase CaWO4 nanoparticles (Ov-a/c-CaWO4 NPs) with enhanced radiodynamic effect are synthesized for radiodynamic-immunotherapy of cancer. The phase composition and oxygen vacancy content of CaWO4 can be easily tuned by adjusting the solvothermal temperature. More intriguingly, the amorphous/crystalline interfaces and abundant oxygen vacancies accelerate charge carrier transfer and suppress e--h+ recombination, respectively, enabling synergistically improved ROS production from X-ray-irradiated Ov-a/c-CaWO4 NPs. In addition to directly inducing oxidative damage of cancer cells, radiodynamic generation of ROS also boosts immunogenic cell death to provoke a systemic antitumor immune response, thereby allowing the inhibition of both primary and distant tumors as well as cancer metastasis. This study establishes a synergistic enhancement strategy involving the integration of phase and defect engineering to improve the ROS generation capacity of radiodynamic-immunotherapeutic anticancer nanoagents.

Tailoring cell-inspired biomaterials to fuel cancer therapy

Cancer stands as a predominant cause of mortality across the globe. Traditional cancer treatments, including surgery, radiotherapy, and chemotherapy, are effective yet face challenges like normal tissue damage, complications, and drug resistance. Biomaterials, with their advantages of high efficacy, targeting, and spatiotemporal controllability, have been widely used in cancer treatment. However, the biocompatibility limitations of traditional synthetic materials have restricted their clinical translation and application. Natural cell-inspired biomaterials inherently possess the targeting abilities of cells, biocompatibility, and immune evasion capabilities. Therefore, cell-inspired biomaterials can be used alone or in combination with other drugs or treatment strategies for cancer therapy. In this review, we first introduce the timeline of key milestones in cell-inspired biomaterials for cancer therapy. Then, we describe the abnormalities in cancer including biophysics, cellular biology, and molecular biology aspects. Afterwards, we summarize the design strategies of cell-inspired antitumor biomaterials. Subsequently, we elaborate on the application of antitumor biomaterials inspired by various cell types. Finally, we explore the current challenges and prospects of cell-inspired antitumor materials. This review aims to provide new opportunities and references for the development of antitumor cell-inspired biomaterials.

Cocktail strategy-based nanomedicine: A synergistic cascade of starvation, NIR-II photothermal, and gas therapy for enhanced tumor immunotherapy

Immunotherapy has emerged as a highly promising strategy in the realm of cancer treatment, wherein immunogenic cell death (ICD) is considered a potential trigger for anti-tumor immunity by inducing adaptive immunity to dying cell antigens. This process is often accompanied by the exposure, active secretion, or passive release of a large number of damage-associated molecular patterns (DAMPs), which activate dendritic cells (DCs) and enhance their antigen-presenting capacity. Subsequently, it promotes the recruitment and activation of cytotoxic T lymphocytes, ultimately leading to tumor growth inhibition. In addition, polarizing the M2 phenotype of tumor-associated macrophages (TAMs) to the M1 phenotype is another way to activate anti-tumor immunity, which can further enhance the effect of anti-tumor immunotherapy. In this study, we engineered a composite nanoparticle of UiO-66-NH2@Gold nanoshells@GOx-P-Arg (denoted as UGsGP). The gold nano shells in UGsGP exhibit a broad Near-Infrared-II (NIR-II) absorption to give a high photothermal conversion efficiency and achieve photothermal therapy (PTT). The GOx in UGsGP involves the breakdown of glucose, which results in a decrease in ATP levels and an inhibition of HSP90 and HSP70 production, ultimately enhancing the heat sensitivity of the tumor for PTT. In addition, GOx-mediated starvation therapy by glucose exhaustion produces a substantial amount of hydrogen peroxide (H2O2), which can then react with P-Arg to produce intratumoral NO Thus, the synergistic effect of PTT resensitization, the photothermally-enhanced GOx-mediated starvation, and NO-based gas therapy promote the induction of ICD and the polarization of TAMs. The combination therapy exhibits significant antitumor effects both in vitro and in vivo. STATEMENT OF SIGNIFICANCE: (1) Gold nanoshells on the surface of UiO-66-NH2 display a broad absorption spectrum ranging from 900 to 1700 nm, combined with a high photothermal conversion efficiency of 74.0 %, demonstrating their remarkable ability to harness and convert light energy into heat for effective tumor ablation. (2) Under laser irradiation, GOx within the UGsGPs effectively consumes glucose, increasing intratumoral H2O2 levels, which then reacts with P-Arg to produce NO within the tumor. Concurrently, the reduction in ATP levels suppresses HSP90 and HSP70 production, thereby enhancing the tumor's sensitivity to photothermal therapy. (3) The synergistic combination of NO gas therapy, starvation therapy, and PTT promotes ICD induction and TAM polarization, thereby improving the therapeutic outcomes for primary and distant tumors.

Nano-Oncologic Vaccine for Boosting Cancer Immunotherapy: The Horizons in Cancer Treatment

Nano-oncologic vaccines represent a groundbreaking approach in the field of cancer immunotherapy, leveraging the unique advantages of nanotechnology to enhance the effectiveness and specificity of cancer treatments. These vaccines utilize nanoscale carriers to deliver tumor-associated antigens and immunostimulatory adjuvants, facilitating targeted immune activation and promoting robust antitumor responses. By improving antigen presentation and localizing immune activation within the tumor microenvironment, nano-oncologic vaccines can significantly increase the efficacy of cancer immunotherapy, particularly when combined with other treatment modalities. This review highlights the mechanisms through which nano-oncologic vaccines operate, their potential to overcome existing limitations in cancer treatment, and ongoing advancements in design. Additionally, it discusses the targeted delivery approach, such as EPR effects, pH response, ultrasonic response, and magnetic response. The combination therapy effects with photothermal therapy, radiotherapy, or immune checkpoint inhibitors are also discussed. Overall, nano-oncologic vaccines hold great promise for changing the landscape of cancer treatment and advancing personalized medicine, paving the way for more effective therapeutic strategies tailored to individual patient needs.

Predictive value of dendritic cell-related genes for prognosis and immunotherapy response in lung adenocarcinoma

BACKGROUND

Patients with lung adenocarcinoma (LUAD) receiving drug treatment often have an unpredictive response and there is a lack of effective methods to predict treatment outcome for patients. Dendritic cells (DCs) play a significant role in the tumor microenvironment and the DCs-related gene signature may be used to predict treatment outcome. Here, we screened for DC-related genes to construct a prognostic signature to predict prognosis and response to immunotherapy in LUAD patients.

METHODS

DC-related biological functions and genes were identified using single-cell RNA sequencing (scRNA-seq) and bulk RNA sequencing. DCs-related gene signature (DCRGS) was constructed using integrated machine learning algorithms. Expression of key genes in clinical samples was examined by real-time q-PCR. Performance of the prognostic model, DCRGS, for the prognostic evaluation, was assessed using a multiple time-dependent receiver operating characteristic (ROC) curve, the R package, "timeROC", and validated using GEO datasets.

RESULTS

Analysis of scRNA-seq data showed that there is a significant upregulation of LGALS9 expression in DCs isolated from malignant pleural effusion samples. Leveraging the Coxboost and random survival forest combination algorithm, we filtered out six DC-related genes on which a prognostic prediction model, DCRGS, was established. A high predictive capability nomogram was constructed by combining DCRGS with clinical features. We found that patients with a high-DCRGS score had immunosuppression, activated tumor-associated pathways, and elevated somatic mutational load and copy number variant load. In contrast, patients in the low-DCRGS subgroup were resistant to chemotherapy but sensitive to the CTLA-4 immune checkpoint inhibitor and targeted therapy.

CONCLUSION

We have innovatively established a deep learning-based prediction model, DCRGS, for the prediction of the prognosis of patients with LUAD. The model possesses a strong prognostic prediction performance with high accuracy and sensitivity and could be clinically useful to guide the management of LUAD. Furthermore, the findings of this study could provide an important reference for individualized clinical treatment and prognostic prediction of patients with LUAD.

CAR T Cell Nanosymbionts: Revealing the Boundless Potential of a New Dyad

Cancer treatment has traditionally focused on eliminating tumor cells but faces challenges such as resistance and toxicity. A promising direction involves targeting the tumor microenvironment using CAR T cell immunotherapy, which has shown potential for treating relapsed and refractory cancers but is limited by high costs, resistance, and toxicity, especially in solid tumors. The integration of nanotechnology into ICAM cell therapy, a concept we have named "CAR T nanosymbiosis", offers new opportunities to overcome these challenges. Nanomaterials can enhance CAR T cell delivery, manufacturing, activity modulation, and targeting of the tumor microenvironment, providing better control and precision. This approach aims to improve the efficacy of CAR T cells against solid tumors, reduce associated toxicities, and ultimately enhance patient outcomes. Several studies have shown promising results, and developing this therapy further is essential for increasing its accessibility and effectiveness. Our "addition by subtraction model" synthesizes these multifaceted elements into a unified strategy to advance cancer treatment paradigms.

STING-activating dendritic cell-targeted nanovaccines that evoke potent antigen cross-presentation for cancer immunotherapy

Recently, nanovaccine-based immunotherapy has been robustly investigated due to its potential in governing the immune response and generating long-term protective immunity. However, the presentation of a tumor peptide-major histocompatibility complex to T lymphocytes is still a challenge that needs to be addressed for eliciting potent antitumor immunity. Type 1 conventional dendritic cell (cDC1) subset is of particular interest due to its pivotal contribution in the cross-presentation of exogenous antigens to CD8+ T cells. Here, the DC-derived nanovaccine (denoted as Si9GM) selectively targets cDC1s with marginal loss of premature antigen release for effective stimulator of interferon genes (STING)-mediated antigen cross-presentation. Bone marrow dendritic cell (BMDC)-derived membranes, conjugated to cDC1-specific antibody (αCLEC9A) and binding to tumor peptide (OVA257-264), are coated onto dendrimer-like polyethylenimine (PEI)-grafted silica nanoparticles. Distinct molecular weight-cargos (αCLEC9A-OVA257-264 conjugates and 2'3'-cGAMP STING agonists) are loaded in hierarchical center-radial pores that enables lysosome escape for potent antigen-cross presentation and activates interferon type I, respectively. Impressively, Si9GM vaccination leads to the upregulation of cytotoxic T cells, a reduction in tumor regulatory T cells (Tregs), M1/M2 macrophage polarization, and immune response that synergizes with αPD-1 immune checkpoint blockade. This nanovaccine fulfills a dual role for both direct T cell activation as an artificial antigen-presenting cell and DC subset maturation, indicating its utility in clinical therapy and precision medicine.

New insights for the development of efficient DNA vaccines

Despite the great potential of DNA vaccines for a broad range of applications, ranging from prevention of infections, over treatment of autoimmune and allergic diseases to cancer immunotherapies, the implementation of such therapies for clinical treatment is far behind the expectations up to now. The main reason is the poor immunogenicity of DNA vaccines in humans. Consequently, the improvement of the performance of DNA vaccines in vivo is required. This mini-review provides an overview of the current state of DNA vaccines and the various strategies to enhance the immunogenic potential of DNA vaccines, including (i) the optimization of the DNA construct itself regarding size, nuclear transfer and transcriptional regulation; (ii) the use of appropriate adjuvants; and (iii) improved delivery, for example, by careful choice of the administration route, physical methods such as electroporation and nanomaterials that may allow cell type-specific targeting. Moreover, combining nanoformulated DNA vaccines with other immunotherapies and prime-boost strategies may help to enhance success of treatment.

A Biomimetic Autophagosomes-Based Nanovaccine Boosts Anticancer Immunity

Personalized cancer vaccines based on tumor cell lysates offer promise for cancer immunotherapy yet fail to elicit a robust therapeutic effect due to the weak immunogenicity of tumor antigens. Autophagosomes, obtained from pleural effusions and ascites of cancer patients, have been identified as abundant reservoirs of tumor neoantigens that exhibit heightened immunogenicity. However, their potential as personalized cancer vaccines have been constrained by suboptimal lymphatic-targeting performances and challenges in antigen-presenting cell endocytosis. Here,a reinforced biomimetic autophagosome-based (BAPs) nanovaccine generated by precisely amalgamating autophagosome-derived neoantigens and two types of adjuvants capable of targeting lymph nodes is developed to potently elicit antitumor immunity. The redox-responsive BAPs facilitate cytosolic vaccine opening within antigen-presenting cells, thereby exposing adjuvants and antigens to stimulate a strong immune response. BAPs evoke broad-spectrum T-cell responses, culminating in the effective eradication of 71.4% of established tumors. Notably, BAPs vaccination triggers enduring T-cell responses that confer robust protection, with 100% of mice shielded against tumor rechallenge and a significant reduction in tumor incidence by 87.5%. Furthermore, BAPs synergize with checkpoint blockade therapy to inhibit tumor growth in the poorly immunogenic breast cancer model. The biomimetic approach presents a powerful nanovaccine formula with high versatility for personalized cancer immunotherapy.

Engineered Cancer Nanovaccines: A New Frontier in Cancer Therapy

Vaccinations are essential for preventing and treating disease, especially cancer nanovaccines, which have gained considerable interest recently for their strong anti-tumor immune capabilities. Vaccines can prompt the immune system to generate antibodies and activate various immune cells, leading to a response against tumor tissues and reducing the negative effects and recurrence risks of traditional chemotherapy and surgery. To enhance the flexibility and targeting of vaccines, nanovaccines utilize nanotechnology to encapsulate or carry antigens at the nanoscale level, enabling more controlled and precise drug delivery to enhance immune responses. Cancer nanovaccines function by encapsulating tumor-specific antigens or tumor-associated antigens within nanomaterials. The small size of these nanomaterials allows for precise targeting of T cells, dendritic cells, or cancer cells, thereby eliciting a more potent anti-tumor response. In this paper, we focus on the classification of carriers for cancer nanovaccines, the roles of different target cells, and clinically tested cancer nanovaccines, discussing strategies for effectively inducing cytotoxic T lymphocytes responses and optimizing antigen presentation, while also looking ahead to the translational challenges of moving from animal experiments to clinical trials.

Inorganic Nanoparticle Functionalization Strategies in Immunotherapeutic Applications

Nanotechnology has been increasingly utilized in anticancer treatment owing to its ability of engineering functional nanocarriers that enhance therapeutic effectiveness while minimizing adverse effects. Inorganic nanoparticles (INPs) are prevalent nanocarriers to be customized for a wide range of anticancer applications, including theranostics, imaging, targeted drug delivery, and therapeutics, because they are advantageous for their superior biocompatibility, unique optical properties, and capacity of being modified via versatile surface functionalization strategies. In the past decades, the high adaptation of INPs in this emerging immunotherapeutic field makes them good carrier options for tumor immunotherapy and combination immunotherapy. Tumor immunotherapy requires targeted delivery of immunomodulating therapeutics to tumor locations or immunological organs to provoke immune cells and induce tumor-specific immune response while regulating immune homeostasis, particularly switching the tumor immunosuppressive microenvironment. This review explores various INP designs and formulations, and their employment in tumor immunotherapy and combination immunotherapy. We also introduce detailed demonstrations of utilizing surface engineering tactics to create multifunctional INPs. The generated INPs demonstrate the abilities of stimulating and enhancing the immune response, specific targeting, and regulating cancer cells, immune cells, and their resident microenvironment, sometimes along with imaging and tracking capabilities, implying their potential in multitasking immunotherapy. Furthermore, we discuss the promises of INP-based combination immunotherapy in tumor treatments.

Mannosylated Fluoropolypeptide Nanovaccines Remodeling Tumor Immunosuppressive Microenvironment to Achieve Highly Potent Cancer Immunotherapy

It is challenging for nanovaccines (NVs) to effectively deliver antigens/neoantigens to prime specifically potent immunities and remodel immunosuppressive tumor microenvironment (TME) for combating immune "cold" cancers. Herein, a novel kind of mannosylated fluoropolypeptide NVs of MFPCOFG (i.e., mannosylated fluoropoly(D,L-cysteine) ovalbumin-loaded Fe2+-gallic acid) is designed that synergistically integrates triple antigen-metal-thermoimmunity to remodel immunosuppressive TME and achieve highly potent immunities. MFPCOFG plus near-infrared irradiation (NIR) effectively facilitated antigen uptake and escape, induced the maturation and antigen cross-presentations of dendritic cells and macrophages, polarized anti-inflammatory macrophage phenotype M2 into tumoricial M1, primed potent CD4+/CD8+T cells responses, proinflammatory cytokines secretion and immune memory effects, showcasing triple antigen-metal-thermoimmunity outperforming combo/mono-immunity. Importantly, both MFPCOFG + NIR and personalized NVs can remarkably enhance the tumor infiltration of CD4+/CD8+T and NK cells to boost potent immunities and long-lasting memory effects, reduce regulatory T (Tregs) and M2 to remodel immunosuppressive TME in B16-OVA and 4T1 models, achieving superior tumor prevention, ablation, and tumor relapse and metastasis inhibition, as further orchestrated with anti-PD-1. Consequently, this work opens up a new avenue to design biocompatible polypeptide nanovaccines with potent immune-priming and TME-remodeling capabilities, holding great potentials to combat immune "cold" cancers with clinic-used anti-PD-1 for cancer immunotherapy and personalized immunotherapy.

Manganese oxide-constructed multifunctional biomimetic nanovaccine for robust tumor-specific T cell priming and chemodynamic therapy

The development of manganese oxide-based chemodynamic immunotherapy is emerging as a key strategy against solid tumors. However, the limited efficacy of nanoplatform in inducing efficient tumor therapeutic effects and creating the prominent antitumor immune responses remains a crucial issue. In this study, we construct a novel multifunctional biomimetic nanovaccine comprising manganese oxide-loaded poly(2-diisopropylaminoethyl methacrylate) (MP) nanoparticles and a coating layer of hybrid cell membrane (RHM) derived from manganese oxide-remodeled 4T1 cells and dendritic cells (DCs) (collectively called MP@RHM) for combination chemodynamic immunotherapy. Compared with the nanovaccines coated with the single cell membrane, the MP@RHM nanovaccine highly efficiently activates both DCs and T cells to boost tumor-specific T cell, owing to the synergistic effects of abundant damage-associated molecular patterns, Mn2+, and T cell-stimulating moieties. Upon peritumoral injection, the MP@RHM nanovaccine targets both the tumor site for focused chemodynamic therapy and the lymph nodes for robust tumor-specific T cell priming, thereby achieving highly efficient chemodynamic immunotherapy. Moreover, as a preventive cancer nanovaccine, MP@RHM generates strong immunological memory to inhibit postoperative tumor metastasis and recurrence. Our study findings highlight a promising approach to construct a multifunctional biomimetic nanovaccine for personalized chemodynamic immunotherapy against solid tumors.

Nanomaterials Boost CAR-T Therapy for Solid Tumors

T cell engineering, particularly via chimeric antigen receptor (CAR) modifications for enhancing tumor specificity, has shown efficacy in treating hematologic malignancies. The extension of CAR-T cell therapy to solid tumors, however, is impeded by several challenges: The absence of tumor-specific antigens, antigen heterogeneity, a complex immunosuppressive tumor microenvironment, and physical barriers to cell infiltration. Additionally, limitations in CAR-T cell manufacturing capacity and the high costs associated with these therapies restrict their widespread application. The integration of nanomaterials into CAR-T cell production and application offers a promising avenue to mitigate these challenges. Utilizing nanomaterials in the production of CAR-T cells can decrease product variability and lower production expenses, positively impacting the targeting and persistence of CAR-T cells in treatment and minimizing adverse effects. This review comprehensively evaluates the use of various nanomaterials in the production of CAR-T cells, genetic modification, and in vivo delivery. It discusses their underlying mechanisms and potential for clinical application, with a focus on improving specificity and safety in CAR-T cell therapy.

Components, Formulations, Deliveries, and Combinations of Tumor Vaccines

Tumor vaccines, an important part of immunotherapy, prevent cancer or kill existing tumor cells by activating or restoring the body's own immune system. Currently, various formulations of tumor vaccines have been developed, including cell vaccines, tumor cell membrane vaccines, tumor DNA vaccines, tumor mRNA vaccines, tumor polypeptide vaccines, virus-vectored tumor vaccines, and tumor-in-situ vaccines. There are also multiple delivery systems for tumor vaccines, such as liposomes, cell membrane vesicles, viruses, exosomes, and emulsions. In addition, to decrease the risk of tumor immune escape and immune tolerance that may exist with a single tumor vaccine, combination therapy of tumor vaccines with radiotherapy, chemotherapy, immune checkpoint inhibitors, cytokines, CAR-T therapy, or photoimmunotherapy is an effective strategy. Given the critical role of tumor vaccines in immunotherapy, here, we look back to the history of tumor vaccines, and we discuss the antigens, adjuvants, formulations, delivery systems, mechanisms, combination therapy, and future directions of tumor vaccines.

Unlocking the power of nanomedicine: Cell membrane-derived biomimetic cancer nanovaccines for cancer treatment

Over the past decades, nanomedicine researchers have dedicated their efforts to developing nanoscale platforms capable of more precisely delivering drug payloads to attack tumors. Cancer nanovaccines are exhibiting a distinctive capability in inducing tumor-specific antitumor responses. Nevertheless, there remain numerous challenges that must be addressed for cancer nanovaccines to evoke sufficient therapeutic effects. Cell membrane-derived nanovaccines are an emerging class of cancer vaccines that comprise a synthetic nanoscale core camouflaged by naturally derived cell membranes. The specific cell membrane has a biomimetic nanoformulation with several distinctive abilities, such as immune evasion, enhanced biocompatibility, and tumor targeting, typically associated with a source cell. Here, we discuss the advancements of cell membrane-derived nanovaccines and how these vaccines are used for cancer therapeutics. Translational endeavors are currently in progress, and additional research is also necessary to effectively address crucial areas of demand, thereby facilitating the future successful translation of these emerging vaccine platforms.

Advances in antitumor application of ROS enzyme-mimetic catalysts

The rapid growth of research on enzyme-mimetic catalysts (Enz-Cats) is expected to promote further advances in nanomedicine for biological detection, diagnosis and treatment of disease, especially tumors. ROS-based nanomedicines present fascinating potential in antitumor therapy owing to the rapid development of nanotechnology. In this review, we focus on the applications of Enz-Cats based on ROS in antitumor therapy. Firstly, the definition and category of ROS are introduced, and the key factors enhancing ROS levels are carefully elucidated. Then, the rationally engineered Enz-Cats via different synthetic approaches with high ROS-producing efficiencies are comprehensively discussed. Subsequently, oncotherapy application of Enz-Cats is comprehensively discussed, which integrates diverse synergistic treatment modalities and exhibits high efficiency in ROS generation. Finally, the challenges and future research direction of this field are presented. This review is dedicated to unraveling the enigmas surrounding the interplay of nanomedicine and organisms.

Engineering customized nanovaccines for enhanced cancer immunotherapy

Nanovaccines have gathered significant attention for their potential to elicit tumor-specific immunological responses. Despite notable progress in tumor immunotherapy, nanovaccines still encounter considerable challenges such as low delivery efficiency, limited targeting ability, and suboptimal efficacy. With an aim of addressing these issues, engineering customized nanovaccines through modification or functionalization has emerged as a promising approach. These tailored nanovaccines not only enhance antigen presentation, but also effectively modulate immunosuppression within the tumor microenvironment. Specifically, they are distinguished by their diverse sizes, shapes, charges, structures, and unique physicochemical properties, along with targeting ligands. These features of nanovaccines facilitate lymph node accumulation and activation/regulation of immune cells. This overview of bespoke nanovaccines underscores their potential in both prophylactic and therapeutic applications, offering insights into their future development and role in cancer immunotherapy.

The Improved Antigen Uptake and Presentation of Dendritic Cells Using Cell-Penetrating D-octaarginine-Linked PNVA-co-AA as a Novel Dendritic Cell-Based Vaccine

Cancer immunotherapy using antigen-pulsed dendritic cells can induce strong cellular immune responses by priming cytotoxic T lymphocytes. In this study, we pulsed tumor cell lysates with VP-R8, a cell-penetrating D-octaarginine-linked co-polymer of N-vinylacetamide and acrylic acid (PNVA-co-AA), into the DC2.4 murine dendritic cell line to improve antigen uptake and then determined the anti-tumor effect in tumor-bearing mice. DC2.4 cells were pulsed with the cell lysate of EL4, a murine lymphoma cell line, and VP-R8 to generate the DC2.4 vaccine. For the in vivo study, DC2.4 cells pulsed with EL4 lysate and VP-R8 were subcutaneously injected into the inguinal lymph node to investigate the anti-tumor effect against EL4 and EL4-specific T cell immune responses. VP-R8 significantly improved antigen uptake into DC2.4 compared to conventional keyhole limpet hemocyanin (p < 0.05). The expression of MHC class I, MHC class II, and CD86 in DC2.4 cells significantly increased after pulsing tumor lysates with VP-R8 compared to other treatments (p < 0.05). The intra-lymph node injection of DC2.4 pulsed with both VP-R8 and EL4 lysate significantly decreased tumor growth compared to DC2.4 pulsed with KLH and lysates (p < 0.05) and induced tumor-infiltrating CD8T cells. The DC2.4 vaccine also remarkably increased the population of IFN-gamma-producing T cells and CTL activity against EL4 cells. In conclusion, we demonstrated that VP-R8 markedly enhances the efficiency of dendritic cell-based vaccines in priming robust anti-tumor immunity, suggesting its potential as a beneficial additive for dendritic cell-based immunotherapy.

Cell-membrane engineering strategies for clinic-guided design of nanomedicine

Cells are the fundamental units of life. The cell membrane primarily composed of two layers of phospholipids (a bilayer) structurally defines the boundary of a cell, which can protect its interior from external disturbances and also selectively exchange substances and conduct signals from the extracellular environment. The complexity and particularity of transmembrane proteins provide the foundation for versatile cellular functions. Nanomedicine as an emerging therapeutic strategy holds tremendous potential in the healthcare field. However, it is susceptible to recognition and clearance by the immune system. To overcome this bottleneck, the technology of cell membrane coating has been extensively used in nanomedicines for their enhanced therapeutic efficacy, attributed to the favorable fluidity and biocompatibility of cell membranes with various membrane-anchored proteins. Meanwhile, some engineering strategies of cell membranes through various chemical, physical and biological ways have been progressively developed to enable their versatile therapeutic functions against complex diseases. In this review, we summarized the potential clinical applications of four typical cell membranes, elucidated their underlying therapeutic mechanisms, and outlined their current engineering approaches. In addition, we further discussed the limitation of this technology of cell membrane coating in clinical applications, and possible solutions to address these challenges.

Construction of lymph nodes-targeting tumor vaccines by using the principle of DNA base complementary pairing to enhance anti-tumor cellular immune response

Tumor vaccines, a crucial immunotherapy, have gained growing interest because of their unique capability to initiate precise anti-tumor immune responses and establish enduring immune memory. Injected tumor vaccines passively diffuse to the adjacent draining lymph nodes, where the residing antigen-presenting cells capture and present tumor antigens to T cells. This process represents the initial phase of the immune response to the tumor vaccines and constitutes a pivotal determinant of their effectiveness. Nevertheless, the granularity paradox, arising from the different requirements between the passive targeting delivery of tumor vaccines to lymph nodes and the uptake by antigen-presenting cells, diminishes the efficacy of lymph node-targeting tumor vaccines. This study addressed this challenge by employing a vaccine formulation with a tunable, controlled particle size. Manganese dioxide (MnO2) nanoparticles were synthesized, loaded with ovalbumin (OVA), and modified with A50 or T20 DNA single strands to obtain MnO2/OVA/A50 and MnO2/OVA/T20, respectively. Administering the vaccines sequentially, upon reaching the lymph nodes, the two vaccines converge and simultaneously aggregate into MnO2/OVA/A50-T20 particles through base pairing. This process enhances both vaccine uptake and antigen delivery. In vitro and in vivo studies demonstrated that, the combined vaccine, comprising MnO2/OVA/A50 and MnO2/OVA/T20, exhibited robust immunization effects and remarkable anti-tumor efficacy in the melanoma animal models. The strategy of controlling tumor vaccine size and consequently improving tumor antigen presentation efficiency and vaccine efficacy via the DNA base-pairing principle, provides novel concepts for the development of efficient tumor vaccines.

Supramolecular Lipid Nanoparticles Based on Host-Guest Recognition: A New Generation Delivery System of mRNA Vaccines For Cancer Immunotherapy

Dendritic cell (DC) maturation is a crucial process for antigen presentation and the initiation of T cell-mediated immune responses. Toll-like receptors play pivotal roles in stimulating DC maturation and promoting antigen presentation. Here, a novel message RNA (mRNA) cancer vaccine is reported that boosts antitumor efficacy by codelivering an mRNA encoding tumor antigen and a TLR7/8 agonist (R848) to DC using supramolecular lipid nanoparticles (SMLNP) as a delivery platform, in which a new ionizable lipid (N2-3L) remarkably enhances the translation efficiency of mRNA and a β-cyclodextrin (β-CD)-modified ionizable lipid (Lip-CD) encapsulates R848. The incorporation of R848 adjuvant into the mRNA vaccine through noncovalent host-guest complexation significantly promotes DC maturation and antigen presentation after vaccination, thus resulting in superior antitumor efficacy in vivo. Moreover, the antitumor efficacy is further boosted synergized with immune checkpoint blockade by potentiating the anticancer capability of cytotoxic T lymphocytes infiltrated in tumor sites. This work indicates that SMLNP shows brilliant potential as next-generation delivery system in the development of mRNA vaccines with high efficacy.

Antigen Self-Presented Personalized Nanovaccines Boost the Immunotherapy of Highly Invasive and Metastatic Tumors

Dendritic cell (DC)-based vaccines have shown promise in adoptive cell therapy for enhancing the antigen-specific response of antitumor immunity. However, their clinical efficacy is limited by the less-presented tumor-associated antigens (TAAs) through MHC I and low lymph node homing efficiency. Herein, to address these issues, we rationally design and fabricate DC-based nanovaccines by coating Cu2-xSe nanoparticles (CS NPs) with the membrane of matured DCs (named as DCNV(CSD) nanovaccines). We reveal the important roles of CS NPs in the DCNV(CSD) nanovaccines from three aspects: (1) inducing the immunogenic cell death of tumor cells to expose abundant TAAs; (2) promoting the escape of TAAs from the lysosomes of DCs during the antigen presenting process through MHC I; (3) sustainably releasing traces of copper ions to promote the proliferation of T cells. Our DCNV(CSD) nanovaccines are characterized with high expressions of MHC I, CD80, CD86, CCR7, and ICAM-1 proteins, which not only endow them with abundantly processed specific TAAs, but also a strong capability of homing to the lymph nodes. The homing capability of our small DCNV(CSD) nanovaccines is better than that of matured DCs. More importantly, they can elicit the strong response of potent antispecific CD8+ T cells for antitumor immunotherapy, as tested in the treatment of highly invasive glioblastoma and highly metastatic melanoma. Additionally, DCNV(CSD) nanovaccines can generate memory T cells (TEM) in the spleen of mice to effectively prevent the recurrence of treated tumors. This work demonstrates a universal approach to fabricate high-performance DC-based nanovaccines for tumor immunotherapy by using versatile CS NPs.

The quest for nanoparticle-powered vaccines in cancer immunotherapy

Despite recent advancements in cancer treatment, this disease still poses a serious threat to public health. Vaccines play an important role in preventing illness by preparing the body's adaptive and innate immune responses to combat diseases. As our understanding of malignancies and their connection to the immune system improves, there has been a growing interest in priming the immune system to fight malignancies more effectively and comprehensively. One promising approach involves utilizing nanoparticle systems for antigen delivery, which has been shown to potentiate immune responses as vaccines and/or adjuvants. In this review, we comprehensively summarized the immunological mechanisms of cancer vaccines while focusing specifically on the recent applications of various types of nanoparticles in the field of cancer immunotherapy. By exploring these recent breakthroughs, we hope to identify significant challenges and obstacles in making nanoparticle-based vaccines and adjuvants feasible for clinical application. This review serves to assess recent breakthroughs in nanoparticle-based cancer vaccinations and shed light on their prospects and potential barriers. By doing so, we aim to inspire future immunotherapies for cancer that harness the potential of nanotechnology to deliver more effective and targeted treatments.

Global trends in tumor microenvironment-related research on tumor vaccine: a review and bibliometric analysis

Background

Tumor vaccines have become crucial in cancer immunotherapy, but, only a limited number of phase III clinical trials have demonstrated clinical efficacy. The crux of this issue is the inability of tumor vaccines to effectively harmonize the tumor microenvironment with its intricate interplay. One factor that can hinder the effectiveness of vaccines is the natural immunosuppressive element present in the tumor microenvironment. This element can lead to low rates of T-cell response specific to antigens and the development of acquired resistance. Conversely, anticancer vaccines alter the tumor microenvironment in conflicting manners, inducing both immune activation and immunological evasion. Hence, comprehending the correlation between tumor vaccines and the tumor microenvironment would establish a foundation for forthcoming tumor treatment.

Objective

Our review explores the realm of research pertaining to tumor vaccinations and the tumor microenvironment. Our objective is to investigate the correlation between tumor vaccines and the tumor microenvironment within this domain. We then focus our review on the dominant international paradigms in this research field and visually illustrates the historical progression and emergent patterns observed in the past.

Methods

From January 1, 1999 to February 7, 2023, 1420 articles on the interplay between tumor vaccines and the tumor microenvironment were published, according to The Clarivate Web of Science (WOS) database used in our review. A bibliometric review was designed for this collection and consisted of an evaluation. The evaluation encompassed various discernible attributes, including the year of publication, the journals in which the articles were published, the authors involved, the affiliated institutions, the geographical locations of the institutions, the references cited, and the keywords employed.

Results

Between the years 1999 and 2022, publications saw a significant increase, from 3 to 265 annually. With 72 papers published, Frontiers in Immunology had the most manuscripts published. The Cancer Research publication garnered the highest number of citations, amounting to 2874 citations. The United States exerts significant dominance in the subject, with the National Cancer Institute being recognized as a prominent institution in terms of both productivity and influence. Furthermore, Elizabeth M. Jaffee was recognized as the field's most prolific and influential author with 24 publications and 1,756 citations. The co-occurrence cluster analysis was conducted on the top 197 keywords, resulting in the identification of five distinct clusters. The most recent high-frequency keywords, namely immune therapy, dendritic cell, tumor microenvironment, cancer, and vaccine, signify the emerging frontiers in the interaction between tumor vaccines and the tumor microenvironment.

Conclusion

Our review uncovers insights into contemporary trends, global patterns of collaboration, fundamental knowledge, research areas of high interest, and emerging frontiers in the field of TME-targeted vaccines.

Chimeric Exosomes Functionalized with STING Activation for Personalized Glioblastoma Immunotherapy

A critical challenge of existing cancer vaccines is to orchestrate the demands of antigen-enriched furnishment and optimal antigen-presentation functionality within antigen-presenting cells (APCs). Here, a complementary immunotherapeutic strategy is developed using dendritic cell (DC)-tumor hybrid cell-derived chimeric exosomes loaded with stimulator of interferon genes (STING) agonists (DT-Exo-STING) for maximized tumor-specific T-cell immunity. These chimeric carriers are furnished with broad-spectrum antigen complexes to elicit a robust T-cell-mediated inflammatory program through direct self-presentation and indirect DC-to-T immunostimulatory pathway. This chimeric exosome-assisted delivery strategy possesses the merits versus off-the-shelf cyclic dinucleotide (CDN) delivery techniques in both the brilliant tissue-homing capacity, even across the intractable blood-brain barrier (BBB), and the desired cytosolic entry for enhanced STING-activating signaling. The improved antigen-presentation performance with this nanovaccine-driven STING activation further enhances tumor-specific T-cell immunoresponse. Thus, DT-Exo-STING reverses immunosuppressive glioblastoma microenvironments to pro-inflammatory, tumoricidal states, leading to an almost obliteration of intracranial primary lesions. Significantly, an upscaling option that harnesses autologous tumor tissues for personalized DT-Exo-STING vaccines increases sensitivity to immune checkpoint blockade (ICB) therapy and exerts systemic immune memory against post-operative glioma recrudesce. These findings represent an emerging method for glioblastoma immunotherapy, warranting further exploratory development in the clinical realm.

Designing nanodiscs as versatile platforms for on-demand therapy

Nowadays, there has been an increasing utilization of nanomedicines for disease treatment. Nanodiscs (NDs) have emerged as a novel platform technology that garners significant attention in biomedical research and drug discovery. NDs are nanoscale phospholipid bilayer discs capable of incorporating membrane proteins and lipids within a native-like environment. They are assembled using amphiphilic biomacromolecular materials, such as apolipoprotein A1 or membrane scaffold proteins (MSPs), peptides, and styrene-maleic acid polymers (SMAs). NDs possess well-defined sizes and shapes, offering a stable, homogeneous, and biologically relevant environment for studying membrane proteins and lipids. Their unique properties have made them highly desirable for diverse applications, including cancer immunotherapy, vaccine development, antibacterial and antiviral therapy, and treating Alzheimer's disease (AD) and diabetes-related conditions. This review discusses the classifications, advantages, and applications of NDs in disease therapy.

Enhancing Dendritic Cell Activation Through Manganese-Coated Nanovaccine Targeting the cGAS-STING Pathway

Background

Nanovaccines have emerged as a promising vaccination strategy, exhibiting their capacity to deliver antigens and adjuvants to elicit specific immune responses. Despite this potential, optimizing the design and delivery of nanovaccines remains a challenge.

Methods

In this study, we engineered a dendritic mesoporous silica-based nanocarrier enveloped in a metal-phenolic network (MPN) layer containing divalent manganese ions and tannic acid (MSN@MT). This nanocarrier was tailored for antigen loading to serve as a nanovaccine, aiming to activate the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway in dendritic cells (DCs). Our experimental approach encompassed both cellular assays and mouse immunizations, allowing a comprehensive evaluation of the nanovaccine's impact on DC activation and its influence on the generation of antigen-specific T-cell responses.

Results

MSN@MT demonstrated a remarkable enhancement in humoral and cellular immune responses in mice compared to control groups. This highlights the potential of MSN@MT to effectively trigger the cGAS-STING pathway in DCs, resulting in robust immune responses.

Conclusion

Our study introduces MSN@MT, a unique nanocarrier incorporating divalent manganese ions and tannic acid, showcasing its exceptional ability to amplify immune responses by activating the cGAS-STING pathway in DCs. This innovation signifies a stride in refining nanovaccine design for potent immune activation.

Dendritic Nanomedicine with Boronate Bonds for Augmented Chemo-Immunotherapy via Synergistic Modulation of Tumor Immune Microenvironment

Unsatisfied tumor accumulation of chemotherapeutic drugs and a complicated immunosuppressive microenvironment diminish the immune response rate and the therapeutic effect. Surface modification of these drugs with target ligands can promote their cellular internalization, but the modified drugs may be subjected to unexpected immune recognition and clearance. Herein, a phenylboronic acid (PBA) group-shieldable dendritic nanomedicine that integrates an immunogenic cell death (ICD)-inducing agent (epirubicin, Epi) and an indoleamine 2,3-dioxgenase 1 (IDO1) inhibitor (NLG919) is reported for tumor chemo-immunotherapy. This NLG919-loaded Epi-conjugated PEGylated dendrimers bridged with boronate bonds (NLG919@Epi-DBP) maintains a stable nanostructure during circulation. Under a moderate acidic condition, the PBA group exposes to the sialic acid residue on the tumor cell membrane to enhance the internalization and penetration of NLG919@Epi-DBP. At pH 5.0, NLG919@Epi-DBP rapidly disassembles to release the incorporated Epi and NLG919. Epi triggers robust ICD of tumor cells that evokes strong immune response. In addition, inhibition of the IDO1 activity downregulates the metabolism of L-tryptophan to kynurenine, leading to a reduction in the recruitment of immunosuppressive cells and modulation of the tumor immune microenvironment. Collectively, this promising strategy has been demonstrated to evoke robust immune response as well as remodel the immunosuppressive microenvironment for an enhanced chemo-immunotherapeutic effect.

Cell Membrane-Camouflaged Nanoparticles Mediated Nucleic Acids Delivery

Nucleic acids have emerged as promising therapeutic agents for many diseases because of their potential in modulating gene expression. However, the delivery of nucleic acids remains a significant challenge in gene therapy. Although viral vectors have shown high transfection efficiency, concerns regarding teratogenicity or carcinogenicity have been raised. Non-viral vehicles, including cationic polymers, liposomes, and inorganic materials possess advantages in terms of safety, ease of preparation, and low cost. Nevertheless, they also face limitations related to immunogenicity, quick clearance in vivo, and lack of targeting specificity. On the other hand, bioinspired strategies have shown increasing potential in the field of drug delivery, yet there is a lack of comprehensive reviews summarizing the rapid development of bioinspired nanoparticles based on the cell membrane camouflage to construct the nucleic acids vehicles. Herein, we enumerated the current difficulties in nucleic acid delivery with various non-viral vehicles and provided an overview of bioinspired strategies for nucleic acid delivery.

Therapeutic cancer vaccines: advancements, challenges, and prospects

With the development and regulatory approval of immune checkpoint inhibitors and adoptive cell therapies, cancer immunotherapy has undergone a profound transformation over the past decades. Recently, therapeutic cancer vaccines have shown promise by eliciting de novo T cell responses targeting tumor antigens, including tumor-associated antigens and tumor-specific antigens. The objective was to amplify and diversify the intrinsic repertoire of tumor-specific T cells. However, the complete realization of these capabilities remains an ongoing pursuit. Therefore, we provide an overview of the current landscape of cancer vaccines in this review. The range of antigen selection, antigen delivery systems development the strategic nuances underlying effective antigen presentation have pioneered cancer vaccine design. Furthermore, this review addresses the current status of clinical trials and discusses their strategies, focusing on tumor-specific immunogenicity and anti-tumor efficacy assessment. However, current clinical attempts toward developing cancer vaccines have not yielded breakthrough clinical outcomes due to significant challenges, including tumor immune microenvironment suppression, optimal candidate identification, immune response evaluation, and vaccine manufacturing acceleration. Therefore, the field is poised to overcome hurdles and improve patient outcomes in the future by acknowledging these clinical complexities and persistently striving to surmount inherent constraints.

Advances in Cancer Vaccine Research

The use of cancer vaccines is considered a promising therapeutic strategy in clinical oncology, which is achieved by stimulating antitumor immunity with tumor antigens delivered in the form of cells, peptides, viruses, and nucleic acids. The ideal cancer vaccine has many advantages, including low toxicity, specificity, and induction of persistent immune memory to overcome tumor heterogeneity and reverse the immunosuppressive microenvironment. Many therapeutic vaccines have entered clinical trials for a variety of cancers, including melanoma, breast cancer, lung cancer, and others. However, many challenges, including single antigen targeting, weak immunogenicity, off-target effects, and impaired immune response, have hindered their broad clinical translation. In this review, we introduce the principle of action, components (including antigens and adjuvants), and classification (according to applicable objects and preparation methods) of cancer vaccines, summarize the delivery methods of cancer vaccines, and review the clinical and theoretical research progress of cancer vaccines. We also present new insights into cancer vaccine technologies, platforms, and applications as well as an understanding of potential next-generation preventive and therapeutic vaccine technologies, providing a broader perspective for future vaccine design.

Dendritic Cell-Mimicking Nanoparticles Promote mRNA Delivery to Lymphoid Organs

Spleen and lymphoid organs are important targets for messenger RNA (mRNA) delivery in various applications. Current nanoparticle delivery methods rely on drainage to lymph nodes from intramuscular or subcutaneous injections. In difficult-to-transfect antigen-presenting cells (APCs), such as dendritic cells (DCs), effective mRNA transfection remains a significant challenge. In this study, a lymphatic targeting carrier using DC membranes is developed, that efficiently migrated to lymphoid organs, such as the spleen and lymph nodes. The nanoparticles contained an ionizable lipid (YK009), which ensured a high encapsulation efficacy of mRNA and assisted mRNA with endosomal escape after cellular uptake. Dendritic cell-mimicking nanoparticles (DCMNPs) showed efficient protein expression in both the spleen and lymph nodes after intramuscular injections. Moreover, in immunized mice, DCMNP vaccination elicited Spike-specific IgG antibodies, neutralizing antibodies, and Th1-biased SARS-CoV-2-specific cellular immunity. This work presents a powerful vaccine formula using DCMNPs, which represents a promising vaccine candidate for further research and development.

Engineering metal-based hydrogel-mediated tertiary lymphoid structure formation via activation of the STING pathway for enhanced immunotherapy

Tertiary lymphoid structures (TLSs) primarily constructed by multiple immune cells can effectively enhance tumor immune responses, but expediting the formation of TLSs is still an enormous challenge. Herein, a stimulator of interferon gene (STING)-activating hydrogel (ZCCG) was elaborately developed by coordinating Zn2+ with 4,5-imidazole dicarboxylic acid, and simultaneously integrating chitosan (a stimulant of STING pathway activation) and CpG (an agonist of toll-like receptor 9, TLR9) for initiating and activating cGAS-STING and TLR9 pathway-mediated immunotherapy. Moreover, the dual-pathway activation could effectively enhance the infiltration of immune cells and the expression of lymphocyte-recruiting chemokines in the tumor microenvironment (TME), thereby promoting the formation of TLSs and further strengthening tumoricidal immunity. Local administration of the hydrogel could prime systemic immune responses and long-term immune memory and improve the therapeutic effects of programmed death-1 antibody (αPD-1) to inhibit tumor progression, metastasis and recurrence. The engineered hydrogel lays the foundation for tumor immunotherapy strategies based on the enhanced formation of TLSs via the activation of the cGAS-STING and TLR9 pathways.

Carrier-Free Nanovaccine: An Innovative Strategy for Ultrahigh Melanoma Neoantigen Loading

In personalized cancer immunotherapy, developing an effective neoantigen nanovaccine with high immunogenicity is a significant challenge. Traditional nanovaccine delivery systems often require nanocarriers, which can hinder the delivery of the neoantigen and cause significant toxicity. In this study, we present an innovative strategy of carrier-free nanovaccine achieved through direct self-assembly of 2'-fluorinated CpG (2'F-CpG) with melanoma neoantigen peptide (Obsl1). Molecular dynamics simulations demonstrated that the introduction of a fluorine atom into CpG increases the noncovalent interaction between 2'F-CpG and Obsl1, which enhanced the loading of Obsl1 on 2'F-CpG, resulting in the spontaneous formation of a hybrid 2'F-CpG/Obsl1 nanovaccine. This nanovaccine without extra nanocarriers showed ultrahigh Obsl1 loading up to 83.19 wt %, increasing the neoantigen peptide uptake by antigen-presenting cells (APCs). In C57BL/6 mice models, we demonstrated the long-term preventive and therapeutic effects of the prepared 2'F-CpG/Obsl1 nanovaccine against B16F10 melanoma. Immunocellular analysis revealed that the nanovaccine activated innate and adaptive immune responses to cancer cells. Hence, this study established a simple, safe, and effective preparation strategy for a carrier-free neoantigen nanovaccine, which could be adapted for the future design of personalized cancer vaccines in clinical settings.

Immunotherapy: cancer immunotherapy and its combination with nanomaterials and other therapies

Immunotherapy is a new type of tumor treatment after surgery, radiotherapy and chemotherapy, and can be used to manage and destroy tumor cells through activating or strengthening the immune response. Immunotherapy has the benefits of a low recurrence rate and high specificity compared to traditional treatment methods. Immunotherapy has developed rapidly in recent years and has become a research hotspot. Currently, chimeric antigen receptor T-cell immunotherapy and immune checkpoint inhibitors are the most effective tumor immunotherapies in clinical practice. While tumor immunotherapy brings hope to patients, it also faces some challenges and still requires continuous research and progress. Combination therapy is the future direction of anti-tumor treatment. In this review, the main focus is on an overview of the research progress of immune checkpoint inhibitors, cellular therapies, tumor vaccines, small molecule inhibitors and oncolytic virotherapy in tumor treatment, as well as the combination of immunotherapy with other treatments.

Zinc-Organometallic Framework Vaccine Controlled-Release Zn2+ Regulates Tumor Extracellular Matrix Degradation Potentiate Efficacy of Immunotherapy

Tumor extracellular matrix (ECM) not only forms a physical barrier for T cells infiltration, but also regulates multiple immunosuppressive pathways, which is an important reason for immunotherapy failure. The cyclic guanosine monophosphate-adenosine monophosphate synthase-stimulator of interferon genes (cGAS-STING) pathway plays a key role in activating CD8+ T cells, maintaining CD8+ T cells stemness and enhancing the antitumor effect. Herein, a zinc-organometallic framework vaccine (ZPM@OVA-CpG) prepared by self-assembly, which achieves site-directed release of Zn2+ in dendritic cell (DC) lysosomes and tumor microenvironment under acidic conditions, is reported. The vaccine actively targets DC, significantly enhances cGAS-STING signal, promotes DC maturation and antigen cross-presentation, and induces strong activation of CD8+ T cells. Meanwhile, the vaccine reaches the tumor site, releasing Zn2+ , significantly up-regulates the activity of matrix metalloproteinase-2, degrades various collagen components of tumor ECM, effectively alleviates immune suppression, and significantly enhances the tumor infiltration and killing of CD8+ T cells. ZPM@OVA-CpG vaccine not only solves the problem of low antigen delivery efficiency and weak CD8+ T cells activation ability, but also achieves the degradation of tumor ECM via the vaccine for the first time, providing a promising therapeutic platform for the development of efficient novel tumor vaccines.

Site-specific nanoswitch circumventing immune resistance via activating TLR and inhibiting PD-L1/PD-1 axis

Immunotherapy has fundamentally altered cancer treatment; however, its effectiveness is clinically hampered by insufficient intratumoral T lymphocyte infiltration and failed T lymphocyte priming. Additionally, inducing cancer-specific immune responses while sparing normal cells remains challenging. Herein, we developed a redox-activatable polymeric nanoswitch (c-N@IM/JQ) that remained 'off' status in circulation but rapidly switched 'on' after entering the tumor. Toll-like receptor (TLR) 7/8 agonist (imidazoquinoline, IMQ) and bromodomain and extraterminal inhibitor (JQ1) are locked in c-N@IM/JQ with a redox-cleavable linker (switch off). Upon systemic administration, c-N@IM/JQ with c-RGD peptide modification preferentially accumulated at tumor sites and responded to the high glutathione levels to release native IMQ for fully mobilizing T lymphocyte army, and JQ1 for removing the programmed death ligand (PD-L)-1 protection on tumor cells (switch on). These strengthened T lymphocyte armies are easily accessible to these de-protected tumor cells, revitalizing the immune response against tumors.

Intelligent nanomaterials for cancer therapy: recent progresses and future possibilities

Intelligent nanomedicine is currently one of the most active frontiers in cancer therapy development. Empowered by the recent progresses of nanobiotechnology, a new generation of multifunctional nanotherapeutics and imaging platforms has remarkably improved our capability to cope with the highly heterogeneous and complicated nature of cancer. With rationally designed multifunctionality and programmable assembly of functional subunits, the in vivo behaviors of intelligent nanosystems have become increasingly tunable, making them more efficient in performing sophisticated actions in physiological and pathological microenvironments. In recent years, intelligent nanomaterial-based theranostic platforms have showed great potential in tumor-targeted delivery, biological barrier circumvention, multi-responsive tumor sensing and drug release, as well as convergence with precise medication approaches such as personalized tumor vaccines. On the other hand, the increasing system complexity of anti-cancer nanomedicines also pose significant challenges in characterization, monitoring and clinical use, requesting a more comprehensive and dynamic understanding of nano-bio interactions. This review aims to briefly summarize the recent progresses achieved by intelligent nanomaterials in tumor-targeted drug delivery, tumor immunotherapy and temporospatially specific tumor imaging, as well as important advances of our knowledge on their interaction with biological systems. In the perspective of clinical translation, we have further discussed the major possibilities provided by disease-oriented development of anti-cancer nanomaterials, highlighting the critical importance clinically-oriented system design.

Engineered Living Materials for Advanced Diseases Therapy

Natural living materials serving as biotherapeutics exhibit great potential for treating various diseases owing to their immunoactivity, tissue targeting, and other biological activities. In this review, the recent developments in engineered living materials, including mammalian cells, bacteria, viruses, fungi, microalgae, plants, and their active derivatives that are used for treating various diseases are summarized. Further, the future perspectives and challenges of such engineered living material-based biotherapeutics are discussed to provide considerations for future advances in biomedical applications.