Dendritic Cell-Based Immunotherapy: State of the Art and Beyond

Engineered mitochondria exert potent antitumor immunity as a cancer vaccine platform

The preferable antigen delivery profile accompanied by sufficient adjuvants favors vaccine efficiency. Mitochondria, which feature prokaryotic characteristics and contain various damage-associated molecular patterns (DAMPs), are easily taken up by phagocytes and simultaneously activate innate immunity. In the current study, we established a mitochondria engineering platform for generating antigen-enriched mitochondria as cancer vaccine. Ovalbumin (OVA) and tyrosinase-related protein 2 (TRP2) were used as model antigens to synthesize fusion proteins with mitochondria-localized signal peptides. The lentiviral infection system was then employed to produce mitochondrial vaccines containing either OVA or TRP2. Engineered OVA- and TRP2-containing mitochondria (OVA-MITO and TRP2-MITO) were extracted and evaluated as potential cancer vaccines. Impressively, the engineered mitochondria vaccine demonstrated efficient antitumor effects when used as both prophylactic and therapeutic vaccines in murine tumor models. Mechanistically, OVA-MITO and TRP2-MITO potently recruited and activated dendritic cells (DCs) and induced a tumor-specific cell-mediated immunity. Moreover, DC activation by mitochondria vaccine critically involves TLR2 pathway and its lipid agonist, namely, cardiolipin derived from the mitochondrial membrane. The results demonstrated that engineered mitochondria are natively well-orchestrated carriers full of immune stimulants for antigen delivery, which could preferably target local dendritic cells and exert strong adaptive cellular immunity. This proof-of-concept study established a universal platform for vaccine construction with engineered mitochondria bearing alterable antigens for cancers as well as other diseases.

Dendritic cells pulsed with penetratin-OLFM4 inhibit the growth and metastasis of melanoma in mice

Cancer stem cells (CSCs) can self-renew and differentiate, contributing to tumor heterogeneity, metastasis, and recurrence. Their resistance to therapies, including immunotherapy, underscores the importance of targeting them for complete remission and relapse prevention. Olfactomedin 4 (OLFM4), a marker associated with various cancers such as colorectal cancer, is expressed on CSCs promoting immune evasion and tumorigenesis. However, its potential as a target for CSC-specific immunotherapy remains underexplored. The primary aim of this study is to evaluate the effectiveness of targeting OLFM4 with dendritic cell (DC)-based vaccines in inhibiting tumor growth and metastasis. To improve antigen delivery and immune response, OLFM4 was conjugated with a protein-transduction domain (PTD) from the antennapedia of Drosophila called penetratin, creating a fusion protein (P-OLFM4). The efficacy of DCs pulsed with P-OLFM4 (DCs [P-OLFM4]) was compared to DCs pulsed with OLFM4 (DCs [OLFM4]) and PBS (DCs [PBS]). DCs [P-OLFM4] inhibited tumor growth by 91.2 % and significantly reduced lung metastasis of OLFM4+ melanoma cells by 97 %, compared to the DCs [PBS]. DCs [OLFM4] also demonstrated a reduction in lung metastasis by 59.7 % compared to DCs [PBS]. Immunization with DCs [P-OLFM4] enhanced OLFM4-specific T-cell proliferation, interferon-γ production, and cytotoxic T cell activity in mice. The results indicate that OLFM4 is a viable target for CSC-focused immunotherapy. DC [P-OLFM4] vaccines can elicit robust immune responses, significantly inhibiting tumor growth and metastasis. This strategy holds promise for developing more effective cancer treatments that specifically target CSCs, potentially leading to better patient outcomes by reducing the likelihood of tumor relapse and metastasis.

Enhancing Dendritic Cell Cancer Vaccination: The Synergy of Immune Checkpoint Inhibitors in Combined Therapies

Dendritic cell (DC) cancer vaccines are a promising therapeutic approach, leveraging the immune system to fight tumors. These vaccines utilize DCs' ability to present tumor-associated antigens to T cells, triggering a robust immune response. DC vaccine development has progressed through three generations. The first generation involved priming DCs with tumor-associated antigens or messenger RNA outside the body, showing limited clinical success. The second generation improved efficacy by using cytokine mixtures and specialized DC subsets to enhance immunogenicity. The third generation used blood-derived DCs to elicit a stronger immune response. Clinical trials indicate that cancer vaccines have lower toxicity than traditional cytotoxic treatments. However, achieving significant clinical responses with DC immunotherapy remains challenging. Combining DC vaccines with immune checkpoint inhibitors (ICIs), such as anticytotoxic T-lymphocyte Antigen 4 and antiprogrammed death-1 antibodies, has shown promise by enhancing T-cell responses and improving clinical outcomes. These combinations can transform non-inflamed tumors into inflamed ones, boosting ICIs' efficacy. Current research is exploring new checkpoint targets like LAG-3, TIM-3, and TIGIT, considering their potential with DC vaccines. Additionally, engineering T cells with chimeric antigen receptors or T-cell receptors could further augment the antitumor response. This comprehensive strategy aims to enhance cancer immunotherapy, focusing on increased efficacy and improved patient survival rates.

Cancer stem cells: advances in knowledge and implications for cancer therapy

Cancer stem cells (CSCs), a small subset of cells in tumors that are characterized by self-renewal and continuous proliferation, lead to tumorigenesis, metastasis, and maintain tumor heterogeneity. Cancer continues to be a significant global disease burden. In the past, surgery, radiotherapy, and chemotherapy were the main cancer treatments. The technology of cancer treatments continues to develop and advance, and the emergence of targeted therapy, and immunotherapy provides more options for patients to a certain extent. However, the limitations of efficacy and treatment resistance are still inevitable. Our review begins with a brief introduction of the historical discoveries, original hypotheses, and pathways that regulate CSCs, such as WNT/β-Catenin, hedgehog, Notch, NF-κB, JAK/STAT, TGF-β, PI3K/AKT, PPAR pathway, and their crosstalk. We focus on the role of CSCs in various therapeutic outcomes and resistance, including how the treatments affect the content of CSCs and the alteration of related molecules, CSCs-mediated therapeutic resistance, and the clinical value of targeting CSCs in patients with refractory, progressed or advanced tumors. In summary, CSCs affect therapeutic efficacy, and the treatment method of targeting CSCs is still difficult to determine. Clarifying regulatory mechanisms and targeting biomarkers of CSCs is currently the mainstream idea.

In Situ Hydrogel Modulates cDC1-Based Antigen Presentation and Cancer Stemness to Enhance Cancer Vaccine Efficiency

Effective presentation of antigens by dendritic cells (DC) is essential for achieving a robust cytotoxic T lymphocytes (CTLs) response, in which cDC1 is the key DC subtype for high-performance activation of CTLs. However, low cDC1 proportion, complex process, and high cost severely hindered cDC1 generation and application. Herein, the study proposes an in situ cDC1 recruitment and activation strategy with simultaneous inhibiting cancer stemness for inducing robust CTL responses and enhancing the anti-tumor effect. Fms-like tyrosine kinase 3 ligand (FLT3L), Poly I:C, and Nap-CUM (NCUM), playing the role of cDC1 recruitment, cDC1 activation, inducing antigen release and decreasing tumor cell stemness, respectively, are co-encapsulated in an in situ hydrogel vaccine (FP/NCUM-Gel). FP/NCUM-Gel is gelated in situ after intra-tumoral injection. With the near-infrared irradiation, tumor cell immunogenic cell death occurred, tumor antigens and immunogenic signals are released in situ. cDC1 is recruited to tumor tissue and activated for antigen cross-presentation, followed by migrating to lymph nodes and activating CTLs. Furthermore, tumor cell stemness are inhibited by napabucasin, which can help CTLs to achieve comprehensive tumor killing. Collectively, the proposed strategy of cDC1 in situ recruitment and activation combined with stemness inhibition provides great immune response and anti-tumor potential, providing new ideas for clinical tumor vaccine design.

The functional role of L-fucose on dendritic cell function and polarization

Despite significant advances in the development and refinement of immunotherapies administered to combat cancer over the past decades, a number of barriers continue to limit their efficacy. One significant clinical barrier is the inability to mount initial immune responses towards the tumor. As dendritic cells are central initiators of immune responses in the body, the elucidation of mechanisms that can be therapeutically leveraged to enhance their functions to drive anti-tumor immune responses is urgently needed. Here, we report that the dietary sugar L-fucose can be used to enhance the immunostimulatory activity of dendritic cells (DCs). L-fucose polarizes immature myeloid cells towards specific DC subsets, specifically cDC1 and moDC subsets. In vitro, L-fucose treatment enhances antigen uptake and processing of DCs. Furthermore, our data suggests that L-fucose-treated DCs increase stimulation of T cell populations. Consistent with our functional assays, single-cell RNA sequencing of intratumoral DCs from melanoma- and breast tumor-bearing mice confirmed transcriptional regulation and antigen processing as pathways that are significantly altered by dietary L-fucose. Together, this study provides the first evidence of the ability of L-fucose to bolster DC functionality and provides rational to further investigate how L-fucose can be used to leverage DC function in order to enhance current immunotherapy.

The Simultaneous Effects of miR-145-5p and hsa-let-7a-3p on Colorectal Tumorigenesis: In Vitro Evidence

Purpose

MicroRNAs (miRNAs) are a group of small regulatory non-coding RNAs, which are dysregulated through tumor progression. let-7 and MIR-145 are both tumor suppressor microRNAs that are downregulated in a wide array of cancers including colorectal cancer (CRC).

Methods

This study was aimed to investigate the effect of simultaneous replacement of these two tumor suppressor miRNAs on proliferation, apoptosis, and migration of CRC cells. HCT-116 with lower expression levels of hsa-let-7a-3p and MIR-145-5p was selected for functional investigations. The cells were cultured and transfected with hsa-let-7a and MIR-145, separately and in combination. Cell viability and apoptosis rates were assessed by MTT assay and flow cytometry, respectively. Cell cycle status was further evaluated using flow cytometry and qRT-PCR was employed to evaluate gene expression.

Results

The obtained results showed that exogenous overexpression of MIR-145 and hsa-let-7a in HCT-116 cells could cooperatively decrease CRC cell proliferation and induce sub-G1 cell cycle arrest. Moreover, hsa-let-7a and MIR-145 co-transfection significantly increased apoptosis induction compared to separate transfected cells and control through modulating the expression levels of apoptosis-related genes including Bax, Bcl-2, P53, Caspase-3, Caspase-8, and Caspase-9. Furthermore, qRT-PCR results illustrated that hsa-let-7a and MIR-145 combination more effectively downregulated MMP-9 and MMP-2 expression, as the important modulators of metastasis, compared to the controls.

Conclusion

Taken together, considering that exogenous overexpression of MIR-145 and hsa-let-7a showed cooperative anti-cancer effects on CRC cells, their combination may be considered as a novel therapeutic strategy for the treatment of CRC.

Dendritic Cells in Cancer Immunology and Immunotherapy

Cancer immunotherapy modulates the immune system, overcomes immune escape and stimulates immune defenses against tumors. Dendritic cells (DCs) are professional promoters of immune responses against tumor antigens with the outstanding ability to coordinate the innate and adaptive immune systems. Evidence suggests that there is a decrease in both the number and function of DCs in cancer patients. Therefore, they represent a strong scaffold for therapeutic interventions. DC vaccination (DCV) is safe, and the antitumoral responses induced are well established in solid tumors. Although the addition of checkpoint inhibitors (CPIs) to chemotherapy has provided new options in the treatment of cancer, they have shown no clinical benefit in immune desert tumors or in those tumors with dysfunctional or exhausted T-cells. In this way, DC-based therapy has demonstrated the ability to modify the tumor microenvironment for immune enriched tumors and to potentiate systemic host immune responses as an active approach to treating cancer patients. Application of DCV in cancer seeks to obtain long-term antitumor responses through an improved T-cell priming by enhancing previous or generating de novo immune responses. To date, DCV has induced immune responses in the peripheral blood of patients without a significant clinical impact on outcome. Thus, improvements in vaccines formulations, selection of patients based on biomarkers and combinations with other antitumoral therapies are needed to enhance patient survival. In this work, we review the role of DCV in different solid tumors with their strengths and weaknesses, and we finally mention new trends to improve the efficacy of this immune strategy.

Influence of microbiota-associated metabolic reprogramming on clinical outcome in patients with melanoma from the randomized adjuvant dendritic cell-based MIND-DC trial

Tumor immunosurveillance plays a major role in melanoma, prompting the development of immunotherapy strategies. The gut microbiota composition, influencing peripheral and tumoral immune tonus, earned its credentials among predictors of survival in melanoma. The MIND-DC phase III trial (NCT02993315) randomized (2:1 ratio) 148 patients with stage IIIB/C melanoma to adjuvant treatment with autologous natural dendritic cell (nDC) or placebo (PL). Overall, 144 patients collected serum and stool samples before and after 2 bimonthly injections to perform metabolomics (MB) and metagenomics (MG) as prespecified exploratory analysis. Clinical outcomes are reported separately. Here we show that different microbes were associated with prognosis, with the health-related Faecalibacterium prausnitzii standing out as the main beneficial taxon for no recurrence at 2 years (p = 0.008 at baseline, nDC arm). Therapy coincided with major MB perturbations (acylcarnitines, carboxylic and fatty acids). Despite randomization, nDC arm exhibited MG and MB bias at baseline: relative under-representation of F. prausnitzii, and perturbations of primary biliary acids (BA). F. prausnitzii anticorrelated with BA, medium- and long-chain acylcarnitines. Combined, these MG and MB biomarkers markedly determined prognosis. Altogether, the host-microbial interaction may play a role in localized melanoma. We value systematic MG and MB profiling in randomized trials to avoid baseline differences attributed to host-microbe interactions.

Impaired monocyte-derived dendritic cell phenotype in prostate cancer patients: A phenotypic comparison with healthy donors

BACKGROUND

Dendritic cells (DCs) play a crucial role in immunity. Research on monocyte-derived DCs (Mo-DCs) cancer vaccines is in progress despite limited success in clinical trials. This study focuses on Mo-DCs generated from prostate cancer (PCA) patients, comparing them with DCs from healthy donors (HD-DCs).

METHODS

Mo-DCs were isolated from PCA patient samples, and their phenotype was compared to HD-DCs. Key parameters included monocyte count, CD14 expression, and the levels of maturation markers (HLA-DR, CD80, CD86) were assessed.

RESULTS

PCA samples exhibited a significantly lower monocyte count and reduced CD14 expression compared to healthy samples (p ⟨ 0.0001). Additionally, PCA-DCs expressed significantly lower levels of maturation markers, including HLA-DR, CD80, and CD86, when compared to HD-DCs (p = 0.123, p = 0.884, and p = 0.309, respectively).

CONCLUSION

The limited success of DC vaccines could be attributed to impaired phenotypic characteristics. These observations suggest that suboptimal characteristics of Mo-DCs generated from cancer patient blood samples might contribute to the limited success of DC vaccines. Consequently, this study underscores the need for alternative strategies to enhance the features of Mo-DCs for more effective cancer immunotherapies.

Combined Osteopontin Blockade and Type 2 Classical Dendritic Cell Vaccination as Effective Synergetic Therapy for Conjunctival Melanoma

Angiogenesis and immune protection are essential at the onset of tumorigenesis. Angiogenesis serves to nourish the tumor, and prevention of immune defenses, for example, by dendritic cells (DCs), allows tumor growth. In this study, we investigated whether there are factors with dual functions that are both angiogenic and immunomodulatory and represent a therapeutic target. We analyzed 1) innate immune responses intratumorally and in draining lymph nodes and 2) angiogenic factors in conjunctival melanoma (CM), a potentially lethal malignant tumor at the ocular surface whose immune and vascular responses are largely unknown. For this purpose, an HGF-Cdk4R24C model in immunocompetent C57BL/6 mice was used and revealed that CD103- type 2 classical DC (cDC2s) were the most abundant DC subtype in healthy conjunctiva, whereas in CM, CD103- cDC2s, CD103+ type 1 cDCs, monocyte-derived DCs, and plasmacytoid DCs were significantly increased. In our analysis of angiogenic factors in CM, the examination of 53 angiogenesis-related factors that might interact with DCs identified osteopontin (OPN) as a major tumor-derived protein that interacts with DCs. Consistent with these findings, 3) a dual therapeutic strategy that inhibited tumor cell function by an OPN blocking Ab while enhancing the immune response by cDC2 vaccination resulted in 35% failure of tumor development. Moreover, tumor progression, monocyte-derived DC infiltration, and intratumoral angiogenesis were significantly reduced, whereas survival and CD8+ T cell infiltration were increased in treated mice compared with the control group. Therefore, we identified OPN blockade in combination with cDC2 vaccination as a potential future therapeutic intervention for early stages of CM by combining antiangiogenic and host immune stimulating effects.

Current status and future of cancer vaccines: A bibliographic study

Background

Cancer vaccines are an important component of tumour immunotherapy. An increasing number of studies have shown that cancer vaccines have considerable clinical benefits. With the development of tumour precision medicine, cancer vaccines have become important because of their individualised targeting effects. However, few bibliometric studies have conducted comprehensive systematic reviews in this field. This study aimed to assess the scientific output and trends in cancer vaccine research from a global perspective.

Methods

We collected publications on cancer vaccines from the Web of Science Core Collection database, which was limited to articles and reviews in English. Microsoft Excel, VOS Viewer, and CiteSpace V were used for quantitative and visual analyses.

Results

A total of 7807 articles were included. From 1991 to 2022, the number of publications increased annually. The United States had the highest number of articles published in this field (48.28 %), the highest citation frequency (183,964 times), and the highest H-index (182). The National Institutes of Health topped the list with 476 articles. Schlom J had the highest number of published articles (128) and was the main investigator in this field. The journal, Cancer Immunology Immunotherapy, had published the highest number of articles in related fields. In recent years, tumour microenvironment, immune checkpoint inhibitors, particle vaccines, tumour antigens, and dendritic cells have become research hotspots related to cancer vaccines.

Conclusion

Cancer vaccines are a popular research topic in the field of tumour immunotherapy. Related research and publications will enter a boom stage. "Immune checkpoint inhibitors", "tumour microenvironment" and "dendritic cells" may become future research hotspots, while "T-cell suppressor" is a potential puzzle to be solved.

Injectable Nano-in-Gel Vaccine for Spatial and Temporal Control of Vaccine Kinetics and Breast Cancer Postsurgical Therapy

Breast cancer is the most commonly diagnosed cancer, and surgical resection is the first choice for its treatment. With the development of operation techniques, surgical treatment for breast cancer is evolving toward minimally invasive and breast-conserving approaches. However, breast-conserving surgery is prone to an increased risk of cancer recurrence and is becoming a key challenge that needs to be solved. In this study, we introduce a one-shot injectable nano-in-gel vaccine (NIGel-Vax) for postoperative breast cancer therapy. The NIGel-Vax was constructed by mixing protein antigens with PEI-4BImi-Man adjuvant and then encapsulated in a hydrogel made with oxidized dextran (ODEX) and 4-arm PEG-ONH2. Using 4T1 tumor-extracted proteins as antigen, the NIGel-Vax achieved a 92% tumor suppression rate and a 33% cure rate as a postoperative therapy in the 4T1 tumor model. Using the tumor-associated antigen trophoblast cell-surface antigen 2 (TROP2) protein as the antigen, NIGel-Vax achieved a 96% tumor suppression rate and a 50% cure rate in triple-negative breast cancer (TNBC) models. This design provides an encouraging approach for breast cancer postoperative management.

Population-based high-dimensional analyses identify multiple intrinsic characters for cancer vaccines against lung squamous cell carcinoma

In lung squamous cell carcinoma (LUSC), current cancer vaccines show promising effects, despite a lack of benefit for a large number of patients. We first identified the tumor antigens into shared and private antigens, and determined the population by clustering analysis in public datasets. For vaccine development, The Cancer Genome Atlas (TCGA) and Clinical Proteomic Tumor Analysis Consortium (CPTAC) were collected. WGCNA method was furthermore applied to construct a consensus gene co-expression network based on TCGA and CPTAC datasets. The main analyses in bulk sequencing included survival, clinical features, tumor microenvironment (TME), and pathways enrichment. In addition, single-cell RNA (scRNA) analysis of cancer epithelium dissected consensus subtype. We identified the ideal population for cancer vaccines, and candidate neoantigens including AOC1, COL5A2, LGI2, and POSTN. According to subtype analysis, Lung squamous 1 (LSQ1) type exhibited a higher tumor mutational load (TMB) and copy number but no immune infiltration, whereas lung squamous 2 (LSQ2) tumors had a higher global methylation level and more fibroblasts but had less stemness. Meanwhile, trajectory analysis further revealed that the evolution of TME influenced prognosis. We emphasized specific pathways or targets with the potential for combination immunotherapy by consensus network and single-cell RNA analyses. Anti-androgen therapy has been validated in vitro experiments of LUSC as proof of concept. In conclusion, LSQ1 was linked to immune exclusion and might be utilized for vaccination, while LSQ2 was linked to immune dysfunction and could be used for programmed cell death protein 1 (PD1) blocking therapy.

Breakthroughs in Cancer Immunotherapy: An Overview of T Cell, NK Cell, Mφ, and DC-Based Treatments

Efforts to treat cancer using chimeric antigen receptor (CAR)-T therapy have made astonishing progress and clinical trials against hematopoietic malignancies have demonstrated their use. However, there are still disadvantages which need to be addressed: high costs, and side effects such as Graft-versus-Host Disease (GvHD) and Cytokine Release Syndrome (CRS). Therefore, recent efforts have been made to harness the properties of certain immune cells to treat cancer-not just T cells, but also natural killer (NK) cells, macrophages (Mφ), dendritic cells (DC), etc. In this paper, we will introduce immune cell-based cellular therapies that use various immune cells and describe their characteristics and their clinical situation. The development of immune cell-based cancer therapy fully utilizing the unique advantages of each and every immune cell is expected to enhance the survival of tumor patients owing to their high efficiency and fewer side effects.

Simultaneous dendritic cells targeting and effective endosomal escape enhance sialic acid-modified mRNA vaccine efficacy and reduce side effects

mRNA vaccines are attractive prospects for the development of DC-targeted vaccines; however, no clinical success has been realized because, currently, it is difficult to simultaneously achieve DC targeting and efficient endosomal/lysosomal escape. Herein, we developed a sialic acid (SA)-modified mRNA vaccine that simultaneously achieved both. The SA modification promoted DCs uptake of lipid nanoparticles (LNPs) by 2 times, >90% of SA-modified LNPs rapidly escaped from early endosomes (EEs), avoided entering lysosomes, achieved mRNA simultaneously translated in ribosomes distributed in the cytoplasm and endoplasmic reticulum (ER), significantly improved the transfection efficiency of mRNA LNPs in DCs. Additionally, we applied cleavable PEG-lipids in mRNA vaccines for the first time and found this conducive to cellular uptake and DC targeting. In summary, SA-modified mRNA vaccines targeted DCs efficiently, and showed significantly higher EEs/lysosomal escape efficiency (90% vs 50%), superior tumor treatment effect, and lower side effects than commercially formulated mRNA vaccines.

[Adjuvant treatment of canine splenic hemangiosarcoma with autologous dendritic cell therapy - a prospective, randomized double-blind study]

OBJECTIVE

Canine splenic hemangiosarcomas (HSA) are malignant mesenchymal tumors with a high tendency for metastasis. Median survival times after splenectomy followed by adjuvant chemotherapy usually range between 5 and 8 months. The aim of this prospective randomized double-blinded study was to examine the efficacy of a commercially available dendritic cell therapy (PetBioCell) following splenectomy. In addition, possible side effects of this therapy were evaluated.

MATERIAL AND METHODS

Twenty-one dogs with histologically confirmed splenic HSA without metastasis (stages I or II) were included in the study. Ten dogs received the dendritic cell therapy, and 11 dogs received a placebo. Injections were administered according to the manufacturer's instructions monthly for the first 3 months and then every 3 months until death. Survival times and toxicoses of both groups were compared.

RESULTS

Follow-up data were available for all 21 patients; the observation period ranging until euthanasia or metastasis-related death. One patient that had received the dendritic cell therapy was euthanized due to prostatitis and experienced the longest survival time (668 days). One dog in the placebo-group lived for 448 days after splenectomy. The median survival times in the dendritic cell therapy and the placebo group amounted to 74 and 126 days, respectively. There was no significant difference in tumor-free interval (t(18) = 1.4, p = 0.911) and survival times (t(19) = -0.094, p = 0.463) between the 2 groups. Toxicoses reported in both groups were mild and self-limiting.

CONCLUSION

Immunotherapy using autologous, immature and unprimed dendritic cells according to the PetBioCell method failed to show efficacy on tumor-free interval and survival time in the presented dog population with splenic hemangiosarcoma.

Boosting immunogenic cell death via hollow MnO2-based multiple stimuli-responsive drug delivery systems for improved cancer immunotherapy

Cancer treatment by inducing tumor cell immunogenic cell death (ICD) is critical for tumor therapy. However, ICD activation by single pathway is often limited in practical application due to its low efficiency. In addition, the low pH and anoxic microenvironments in solid tumors greatly limit the effective activation of ICD. Herein, hollow manganese dioxide (H-MnO2) nanomaterials were selected to load both Mitoxantrone (MTZ) and Chlorin e6 (Ce6) due to its hollow structure and ability to release drugs in the acidic environments. Thus, the synergy of photodynamic therapy (PDT), photothermal therapy (PTT) and chemotherapy can induce the process of immunogenic cell death, stimulate the maturation of dendritic cells (DCs), and activate the immune response to kill tumor cells dramatically. Efficient immunotherapeutic effects were obtained when MnO2-C/M-HA was given intravenously to 4T1 tumor-bearing BALB/c mice with 660 nm near-infrared laser irradiation. This study overcame the limitations of monotherapy and provided a multifunctional platform for tumor immunotherapy.

Exploiting innate immunity for cancer immunotherapy

Immunotherapies have revolutionized the treatment paradigms of various types of cancers. However, most of these immunomodulatory strategies focus on harnessing adaptive immunity, mainly by inhibiting immunosuppressive signaling with immune checkpoint blockade, or enhancing immunostimulatory signaling with bispecific T cell engager and chimeric antigen receptor (CAR)-T cell. Although these agents have already achieved great success, only a tiny percentage of patients could benefit from immunotherapies. Actually, immunotherapy efficacy is determined by multiple components in the tumor microenvironment beyond adaptive immunity. Cells from the innate arm of the immune system, such as macrophages, dendritic cells, myeloid-derived suppressor cells, neutrophils, natural killer cells, and unconventional T cells, also participate in cancer immune evasion and surveillance. Considering that the innate arm is the cornerstone of the antitumor immune response, utilizing innate immunity provides potential therapeutic options for cancer control. Up to now, strategies exploiting innate immunity, such as agonists of stimulator of interferon genes, CAR-macrophage or -natural killer cell therapies, metabolic regulators, and novel immune checkpoint blockade, have exhibited potent antitumor activities in preclinical and clinical studies. Here, we summarize the latest insights into the potential roles of innate cells in antitumor immunity and discuss the advances in innate arm-targeted therapeutic strategies.

Reprogramming the lipid metabolism of dendritic cells in tumor immunomodulation and immunotherapy

Dendritic cells (DCs) are the most potent antigen-presenting cells in the human body. They detect and process environmental signals and communicate with T cells to bridge innate and adaptive immunity. Cell activation, function, and survival are closely associated with cellular metabolism. An increasing number of studies have revealed that lipid metabolism affects DC activation as well as innate and acquired immune responses. Combining lipid metabolic regulation with immunotherapy can strengthen the ability of antigen-presentation and T-cell activation of DCs, improve the existing anti-tumor therapy, and overcome the defects of DC-related therapies in the current stage, which has great potential in cancer therapy. This review summarizes the lipid metabolism of DCs under physiological conditions, analyzes the role of reprogramming the lipid metabolism of DCs in tumor immune regulation, and discusses potential immunotherapeutic strategies.

Personalised neoantigen-based therapy in colorectal cancer

Colorectal cancer (CRC) has become one of the most common tumours with high morbidity, mortality and distinctive evolution mechanism. The neoantigens arising from the somatic mutations have become considerable treatment targets in the management of CRC. As cancer-specific aberrant peptides, neoantigens can trigger the robust host immune response and exert anti-tumour effects while minimising the emergence of adverse events commonly associated with alternative therapeutic regimens. In this review, we summarised the mechanism, generation, identification and prognostic significance of neoantigens, as well as therapeutic strategies challenges of neoantigen-based therapy in CRC. The evidence suggests that the establishment of personalised neoantigen-based therapy holds great promise as an effective treatment approach for patients with CRC.

Controlling Antigen Fate in Therapeutic Cancer Vaccines by Targeting Dendritic Cell Receptors

Antigen-presenting cells (APCs) orchestrate immune responses and are therefore of interest for the targeted delivery of therapeutic vaccines. Dendritic cells (DCs) are professional APCs that excel in presentation of exogenous antigens toward CD4+ T helper cells, as well as cytotoxic CD8+ T cells. DCs are highly heterogeneous and can be divided into subpopulations that differ in abundance, function, and phenotype, such as differential expression of endocytic receptor molecules. It is firmly established that targeting antigens to DC receptors enhances the efficacy of therapeutic vaccines. While most studies emphasize the importance of targeting a specific DC subset, we argue that the differential intracellular routing downstream of the targeted receptors within the DC subset should also be considered. Here, we review the mouse and human receptors studied as target for therapeutic vaccines, focusing on antibody and ligand conjugates and how their targeting affects antigen presentation. We aim to delineate how targeting distinct receptors affects antigen presentation and vaccine efficacy, which will guide target selection for future therapeutic vaccine development.

DC vaccine enhances CAR-T cell antitumor activity by overcoming T cell exhaustion and promoting T cell infiltration in solid tumors

OBJECTIVE

Great success has been achieved in CAR-T cell immunotherapy in the treatment of hematological tumors. However, it is particularly difficult in solid tumors, because CAR-T is difficult to enter interior and exert long-term stable immune effects. Dendritic cells (DCs) can not only present tumor antigens but also promote the infiltration of T cells. Therefore, CAR-T cells with the help of DC vaccines are a reliable approach to treat solid tumors.

METHODS

To test whether DC vaccine could promote CAR-T cell therapy in solid tumors, DC vaccine was co-cultured with MSLN CAR-T cells. The in vitro effects of DC vaccine on CAR-T were assessed by measuring cell proliferation, cell differentiation, and cytokine secretion. Effects of DC vaccine on CAR-T were evaluated using mice with subcutaneous tumors in vivo. The infiltration of CAR-T was analyzed using immunofluorescence. The persistence of CAR-T in mouse blood was analyzed using real-time quantitative PCR.

RESULTS

The results showed that DC vaccine significantly enhanced the proliferation potential of MSLN CAR-T cells in vitro. DC vaccines not only promoted the infiltration of CAR-T cells, but also significantly improved the persistence of CAR-T in solid tumors in vivo.

CONCLUSION

In conclusion, this study has demonstrated that DC vaccine can promote CAR-T therapy in solid tumors, which provides the possibility of widespread clinical application of CAR-T cells in the future.

Tumor Abnormality-Oriented Nanomedicine Design

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

Recent Advances in Antitumor Dendritic Cell Vaccines

Background: Dendritic cells (DCs) are the most important antigen-presenting cells in the body and play a key role in antigen recognition, uptake, processing, and presentation and mediate nonspecific immunity and specific immunity. Purpose: To summarize the main findings that DC vaccines are a new immunotherapy scheme combining the strengths of tumor antigens and DCs that can boost the body's identification and clearance of tumors. Methods: In this review, the authors focus on the biological characteristics of DCs, recent advances in the understanding of antitumor mechanisms, and the classification of DC vaccines. Results: The current progress of DC-based vaccine immunotherapy for common tumors with high morbidity or mortality in China were systematically summarize. Conclusions: The DC vaccines combining the strengths of tumor antigens will provide directions to explore reasonable, safe, and effective combination immunotherapy strategies for tumors in the future.

Cancer Vaccine Therapeutics: Limitations and Effectiveness-A Literature Review

In recent years, there has been a surge of interest in tumor microenvironment-associated cancer vaccine therapies. These innovative treatments aim to activate and enhance the body's natural immune response against cancer cells by utilizing specific antigens present in the tumor microenvironment. The goal is to achieve a complete clinical response, where all measurable cancer cells are either eliminated or greatly reduced in size. With their potential to revolutionize cancer treatment, these therapies represent a promising avenue for researchers and clinicians alike. Despite over 100 years of research, the success of therapeutic cancer vaccines has been variable, particularly in advanced cancer patients, with various limitations, including the heterogeneity of the tumor microenvironment, the presence of immunosuppressive cells, and the potential for tumor escape mechanisms. Additionally, the effectiveness of these therapies may be limited by the variability of the patient's immune system response and the difficulty in identifying appropriate antigens for each patient. Despite these challenges, tumor microenvironment-targeted vaccine cancer therapies have shown promising results in preclinical and clinical studies and have the potential to become a valuable addition to current cancer treatment and "curative" options. While chemotherapeutic and monoclonal antibody treatments remain popular, ongoing research is needed to optimize the design and delivery of these therapies and to identify biomarkers that can predict response and guide patient selection. This comprehensive review explores the mechanisms of cancer vaccines, various delivery methods, and the role of adjuvants in improving treatment outcomes. It also discusses the historical background of cancer vaccine research and examines the current state of major cancer vaccination immunotherapies. Furthermore, the limitations and effectiveness of each vaccine type are analyzed, providing insights into the future of cancer vaccine development.

Knowledge Gaps in Generating Cell-Based Drug Delivery Systems and a Possible Meeting with Artificial Intelligence

Cell-based drug delivery systems are new strategies in targeted delivery in which cells or cell-membrane-derived systems are used as carriers and release their cargo in a controlled manner. Recently, great attention has been directed to cells as carrier systems for treating several diseases. There are various challenges in the development of cell-based drug delivery systems. The prediction of the properties of these platforms is a prerequisite step in their development to reduce undesirable effects. Integrating nanotechnology and artificial intelligence leads to more innovative technologies. Artificial intelligence quickly mines data and makes decisions more quickly and accurately. Machine learning as a subset of the broader artificial intelligence has been used in nanomedicine to design safer nanomaterials. Here, how challenges of developing cell-based drug delivery systems can be solved with potential predictive models of artificial intelligence and machine learning is portrayed. The most famous cell-based drug delivery systems and their challenges are described. Last but not least, artificial intelligence and most of its types used in nanomedicine are highlighted. The present Review has shown the challenges of developing cells or their derivatives as carriers and how they can be used with potential predictive models of artificial intelligence and machine learning.

Biomaterials Facilitating Dendritic Cell-Mediated Cancer Immunotherapy

Dendritic cell (DC)-based cancer immunotherapy has exhibited remarkable clinical prospects because DCs play a central role in initiating and regulating adaptive immune responses. However, the application of traditional DC-mediated immunotherapy is limited due to insufficient antigen delivery, inadequate antigen presentation, and high levels of immunosuppression. To address these challenges, engineered biomaterials have been exploited to enhance DC-mediated immunotherapeutic effects. In this review, vital principal components that can enhance DC-mediated immunotherapeutic effects are first introduced. The parameters considered in the rational design of biomaterials, including targeting modifications, size, shape, surface, and mechanical properties, which can affect biomaterial optimization of DC functions, are further summarized. Moreover, recent applications of various engineered biomaterials in the field of DC-mediated immunotherapy are reviewed, including those serve as immune component delivery platforms, remodel the tumor microenvironment, and synergistically enhance the effects of other antitumor therapies. Overall, the present review comprehensively and systematically summarizes biomaterials related to the promotion of DC functions; and specifically focuses on the recent advances in biomaterial designs for DC activation to eradicate tumors. The challenges and opportunities of treatment strategies designed to amplify DCs via the application of biomaterials are discussed with the aim of inspiring the clinical translation of future DC-mediated cancer immunotherapies.

The Role of TLR4 in the Immunotherapy of Hepatocellular Carcinoma: Can We Teach an Old Dog New Tricks?

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer and is a leading cause of cancer-related death worldwide. Immunotherapy has emerged as the mainstay treatment option for unresectable HCC. Toll-like receptor 4 (TLR4) plays a crucial role in the innate immune response by recognizing and responding primarily to bacterial lipopolysaccharides. In addition to its role in the innate immune system, TLR4 has also been implicated in adaptive immunity, including specific anti-tumor immune responses. In particular, the TLR4 signaling pathway seems to be involved in the regulation of several cancer hallmarks, such as the continuous activation of cellular pathways that promote cell division and growth, the inhibition of programmed cell death, the promotion of several invasion and metastatic mechanisms, epithelial-to-mesenchymal transition, angiogenesis, drug resistance, and epigenetic modifications. Emerging evidence further suggests that TLR4 signaling holds promise as a potential immunotherapeutic target in HCC. The aim of this review was to explore the multilayer aspects of the TLR4 signaling pathway, regarding its role in liver diseases and HCC, as well as its potential utilization as an immunotherapy target for HCC.

Signaling pathways involved in the biological functions of dendritic cells and their implications for disease treatment

The ability of dendritic cells (DCs) to initiate and regulate adaptive immune responses is fundamental for maintaining immune homeostasis upon exposure to self or foreign antigens. The immune regulatory function of DCs is strictly controlled by their distribution as well as by cytokines, chemokines, and transcriptional programming. These factors work in conjunction to determine whether DCs exert an immunosuppressive or immune-activating function. Therefore, understanding the molecular signals involved in DC-dependent immunoregulation is crucial in providing insight into the generation of organismal immunity and revealing potential clinical applications of DCs. Considering the many breakthroughs in DC research in recent years, in this review we focused on three basic lines of research directly related to the biological functions of DCs and summarized new immunotherapeutic strategies involving DCs. First, we reviewed recent findings on DC subsets and identified lineage-restricted transcription factors that guide the development of different DC subsets. Second, we discussed the recognition and processing of antigens by DCs through pattern recognition receptors, endogenous/exogenous pathways, and the presentation of antigens through peptide/major histocompatibility complexes. Third, we reviewed how interactions between DCs and T cells coordinate immune homeostasis in vivo via multiple pathways. Finally, we summarized the application of DC-based immunotherapy for autoimmune diseases and tumors and highlighted potential research prospects for immunotherapy that targets DCs. This review provides a useful resource to better understand the immunomodulatory signals involved in different subsets of DCs and the manipulation of these immune signals can facilitate DC-based immunotherapy.

Molecular Imaging of Innate Immunity and Immunotherapy

The innate immune system plays a key role as the first line of defense in various human diseases including cancer, cardiovascular and inflammatory diseases. In contrast to tissue biopsies and blood biopsies, in vivo imaging of the innate immune system can provide whole body measurements of immune cell location and function and changes in response to disease progression and therapy. Rationally developed molecular imaging strategies can be used in evaluating the status and spatio-temporal distributions of the innate immune cells in near real-time, mapping the biodistribution of novel innate immunotherapies, monitoring their efficacy and potential toxicities, and eventually for stratifying patients that are likely to benefit from these immunotherapies. In this review, we will highlight the current state-of-the-art in noninvasive imaging techniques for preclinical imaging of the innate immune system particularly focusing on cell trafficking, biodistribution, as well as pharmacokinetics and dynamics of promising immunotherapies in cancer and other diseases; discuss the unmet needs and current challenges in integrating imaging modalities and immunology and suggest potential solutions to overcome these barriers.

Nanoformulations targeting immune cells for cancer therapy: mRNA therapeutics

The approved worldwide use of two messenger RNA (mRNA) vaccines (BNT162b2 and mRNA-1273) in late 2020 has proven the remarkable success of mRNA therapeutics together with lipid nanoformulation technology in protecting people against coronaviruses during COVID-19 pandemic. This unprecedented and exciting dual strategy with nanoformulations and mRNA therapeutics in play is believed to be a promising paradigm in targeted cancer immunotherapy in future. Recent advances in nanoformulation technologies play a prominent role in adapting mRNA platform in cancer treatment. In this review, we introduce the biologic principles and advancements of mRNA technology, and chemistry fundamentals of intriguing mRNA delivery nanoformulations. We discuss the latest promising nano-mRNA therapeutics for enhanced cancer immunotherapy by modulation of targeted specific subtypes of immune cells, such as dendritic cells (DCs) at peripheral lymphoid organs for initiating mRNA cancer vaccine-mediated antigen specific immunotherapy, and DCs, natural killer (NK) cells, cytotoxic T cells, or multiple immunosuppressive immune cells at tumor microenvironment (TME) for reversing immune evasion. We highlight the clinical progress of advanced nano-mRNA therapeutics in targeted cancer therapy and provide our perspectives on future directions of this transformative integrated technology toward clinical implementation.

Tumor Microenvironment Regulation and Cancer Targeting Therapy Based on Nanoparticles

Although we have made remarkable achievements in cancer awareness and medical technology, there are still tremendous increases in cancer incidence and mortality. However, most anti-tumor strategies, including immunotherapy, show low efficiency in clinical application. More and more evidence suggest that this low efficacy may be closely related to the immunosuppression of the tumor microenvironment (TME). The TME plays a significant role in tumorigenesis, development, and metastasis. Therefore, it is necessary to regulate the TME during antitumor therapy. Several strategies are developing to regulate the TME as inhibiting tumor angiogenesis, reversing tumor associated macrophage (TAM) phenotype, removing T cell immunosuppression, and so on. Among them, nanotechnology shows great potential for delivering regulators into TME, which further enhance the antitumor therapy efficacy. Properly designed nanomaterials can carry regulators and/or therapeutic agents to eligible locations or cells to trigger specific immune response and further kill tumor cells. Specifically, the designed nanoparticles could not only directly reverse the primary TME immunosuppression, but also induce effective systemic immune response, which would prevent niche formation before metastasis and inhibit tumor recurrence. In this review, we summarized the development of nanoparticles (NPs) for anti-cancer therapy, TME regulation, and tumor metastasis inhibition. We also discussed the prospect and potential of nanocarriers for cancer therapy.

Application of injectable hydrogels in cancer immunotherapy

Immunotherapy is a revolutionary and promising approach to cancer treatment. However, traditional cancer immunotherapy often has the disadvantages of limited immune response rate, poor targeting, and low treatment index due to systemic administration. Hydrogels are drug carriers with many advantages. They can be loaded and transported with immunotherapeutic agents, chemical anticancer drugs, radiopharmaceuticals, photothermal agents, photosensitizers, and other therapeutic agents to achieve controlled release of drugs, extend the retention time of drugs, and thus successfully trigger anti-tumor effects and maintain long-term therapeutic effects after administration. This paper reviews recent advances in injectable hydrogel-based cancer immunotherapy, including immunotherapy alone, immunotherapy with combination chemotherapy, radiotherapy, phototherapy, and DNA hydrogel-based immunotherapy. Finally, we review the potential and limitations of injectable hydrogels in cancer immunotherapy.

Tailored PGE2 Immunomodulation of moDCs by Nano-Encapsulated EP2/EP4 Antagonists

Prostaglandin E2 (PGE2) is an important maturation mediator for dendritic cells (DCs). However, increased PGE2 levels in the tumor exert immunosuppressive effects on DCs by signaling through two E-Prostanoid (EP) receptors: EP2 and EP4. Blocking EP-receptor signaling of PGE2 with antagonists is currently being investigated for clinical applications to enhance anti-tumor immunity. In this study, we investigated a new delivery approach by encapsulating EP2/EP4 antagonists in polymeric nanoparticles. The nanoparticles were characterized for size, antagonist loading, and release. The efficacy of the encapsulated antagonists to block PGE2 signaling was analyzed using monocyte-derived DCs (moDCs). The obtained nanoparticles were sized between 210 and 260 nm. The encapsulation efficacy of the EP2/EP4 antagonists was 20% and 17%, respectively, and was further increased with the co-encapsulation of both antagonists. The treatment of moDCs with co-encapsulation EP2/EP4 antagonists prevented PGE2-induced co-stimulatory marker expression. Even though both antagonists showed a burst release within 15 min at 37 °C, the nanoparticles executed the immunomodulatory effects on moDCs. In summary, we demonstrate the functionality of EP2/EP4 antagonist-loaded nanoparticles to overcome PGE2 modulation of moDCs.

Combined therapy with methotrexate nanoconjugate and dendritic cells with downregulated IL-10R expression modulates the tumor microenvironment and enhances the systemic anti-tumor immune response in MC38 murine colon carcinoma

Background

Understanding the negative impact of the tumor microenvironment on the creation of an effective immune response has contributed to the development of new therapeutic anti-cancer strategies. One such solution is combined therapy consisting of chemotherapeutic administration followed by dendritic cell (DC)-based vaccines. The use of cytostatic leads to the elimination of cancer cells, but can also modulate the tumor milieu. Moreover, great efforts are being made to increase the therapeutic outcome of immunotherapy, e.g. by enhancing the ability of DCs to generate an efficient immune response, even in the presence of immunosuppressive cytokines such as IL-10. The study aimed to determine the effectiveness of combined therapy with chemotherapeutic with immunomodulatory potential - HES-MTX nanoconjugate (composed of methotrexate (MTX) and hydroxyethyl starch (HES)) and DCs with downregulated expression of IL-10 receptor stimulated with tumor antigens (DC/shIL-10R/TAg) applied in MC38 murine colon carcinoma model.

Methods

With the use of lentiviral vectors the DCs with decreased expression of IL-10R were obtained and characterized. During in vivo studies MC38-tumor bearing mice received MTX or HES-MTX nanoconjugate as a sole treatment or combined with DC-based immunotherapy containing unmodified DCs or DCs transduced with shRNA against IL-10R (or control shRNA sequence). Tumor volume was monitored during the experiment. One week after the last injection of DC-based vaccines, tumor nodules and spleens were dissected for ex vivo analysis. The changes in the local and systemic anti-tumor immune response were estimated with the use of flow cytometry and ELISA methods.

Results and conclusions

In vitro studies showed that the downregulation of IL-10R expression in DCs enhances their ability to activate the specific anti-tumor immune response. The use of HES-MTX nanoconjugate and DC/shIL-10R/TAg in the therapy of MC38-tumor bearing mice resulted in the greatest tumor growth inhibition. At the local anti-tumor immune response level a decrease in the infiltration of cells with suppressor activity and an increase in the influx of effector cells into MC38 tumor tissue was observed. These changes were crucial to enhance the effective specific immune response at the systemic level, which was revealed in the greatest cytotoxic activity of spleen cells against MC38 cells.

Cancer/testis antigen HEMGN correlated with immune infiltration serves as a prognostic biomarker in lung adenocarcinoma

HEMGN belongs to the Cancer/testis antigens (CTAs), which are expressed in various types of human cancers and have received particular attention in cancer immunotherapy. However, the potential function of HEMGN involved in lung cancer and the immune response is not yet elucidated. HEMGN expression in lung adenocarcinoma (LUAD) was estimated via the Tumor Immune Estimation Resource (TIMER), The Cancer Genome Atlas (TCGA), The University of Alabama at Birmingham Cancer data analysis Portal (UALCAN), and Human Protein Atlas databases. The prognostic role of HEMGN was investigated by Gene Expression Profiling Interactive Analysis (GEPIA), PrognoScan, and Kaplan-Meier plotter databases. The associations between HEMGN and clinicopathological parameters were analyzed with UALCAN database. Then, immunohistochemical and Real-Time Quantitative Reverse Transcription PCR (qRT-PCR) analysis were performed to further verify the associations in tissue or serum samples. Serum from patients were detected for HEMGN antibody by enzyme-linked immunosorbent assay (ELISA). Flow cytometry was used to detect immune cell infiltration in peripheral blood of patients with LUAD. In addition, Gene Set Enrichment Analysis (GSEA) was conducted to investigate the functional role of HEMGN. Furthermore, we obtained the somatic mutation data from the TCGA LUAD dataset and analyzed the mutation profiles with "maftools" package. Finally, we evaluated the associations between HEMGN and immune infiltration level and the characteristic markers of immune cells in TIMER, GEPIA, and CIBERSORT. The mRNA and protein expressions of HEMGN were significantly decreased in LUAD patients. High HEMGN expression was remarkably associated with better prognosis in LUAD patients. The concentration levels of anti-HEMGN antibody in LUAD were significantly higher than that in healthy individuals and were closely correlated with clinical stage. In addition, HEMGN was involved in distinct typical genomic alterations in LUAD. GSEA demonstrated that HEMGN was significantly connected with immunity and substance metabolism. Notably, HEMGN was significantly related to immune infiltrates, including B cells, CD8 + T cells, CD4 + T cells, neutrophils, macrophages, dendritic cells (DCs), and various kinds of functional T cells. Furthermore, HEMGN had a significant association with diverse immune gene markers. HEMGN can be considered as a prognostic biomarker of LUAD and is associated with immune infiltration.

Peripheral gene signatures reveal distinct cancer patient immunotypes with therapeutic implications for autologous DC-based vaccines

Dendritic cells (DCs) have received considerable attention as potential targets for the development of novel cancer immunotherapies. However, the clinical efficacy of DC-based vaccines remains suboptimal, largely reflecting local and systemic immunosuppression at baseline. An autologous DC-based vaccine (DCVAC) has recently been shown to improve progression-free survival and overall survival in randomized clinical trials enrolling patients with lung cancer (SLU01, NCT02470468) or ovarian carcinoma (SOV01, NCT02107937), but not metastatic castration-resistant prostate cancer (SP005, NCT02111577), despite a good safety profile across all cohorts. We performed biomolecular and cytofluorometric analyses on peripheral blood samples collected prior to immunotherapy from 1000 patients enrolled in these trials, with the objective of identifying immunological biomarkers that may improve the clinical management of DCVAC-treated patients. Gene signatures reflecting adaptive immunity and T cell activation were associated with favorable disease outcomes and responses to DCVAC in patients with prostate and lung cancer, but not ovarian carcinoma. By contrast, the clinical benefits of DCVAC were more pronounced among patients with ovarian carcinoma exhibiting reduced expression of T cell-associated genes, especially those linked to T_H2-like signature and immunosuppressive regulatory T (T_REG) cells. Clinical responses to DCVAC were accompanied by signs of antitumor immunity in the peripheral blood. Our findings suggest that circulating signatures of antitumor immunity may provide a useful tool for monitoring the potency of autologous DC-based immunotherapy.

Immunomodulatory role of metalloproteases in cancers: Current progress and future trends

Metalloproteinases (MPs) is a large family of proteinases with metal ions in their active centers. According to the different domains metalloproteinases can be divided into a variety of subtypes mainly including Matrix Metalloproteinases (MMPs), A Disintegrin and Metalloproteases (ADAMs) and ADAMs with Thrombospondin Motifs (ADAMTS). They have various functions such as protein hydrolysis, cell adhesion and remodeling of extracellular matrix. Metalloproteinases expressed in multiple types of cancers and participate in many pathological processes involving tumor genesis and development, invasion and metastasis by regulating signal transduction and tumor microenvironment. In this review, based on the current research progress, we summarized the structure of MPs, their expression and especially immunomodulatory role and mechanisms in cancers. Additionally, a relevant and timely update of recent advances and future directions were provided for the diagnosis and immunotherapy targeting MPs in cancers.

LL-37 as a Powerful Molecular Tool for Boosting the Performance of Ex Vivo-Produced Human Dendritic Cells for Cancer Immunotherapy

Ex vivo-produced dendritic cells (DCs) constitute the core of active cellular immunotherapy (ACI) for cancer treatment. After many disappointments in clinical trials, the current protocols for their preparation are attempting to boost their therapeutic efficacy by enhancing their functionality towards Th1 response and capability to induce the expansion of cytotoxic tumor-specific CD8⁺ T cells. LL-37 is an antimicrobial peptide with strong immunomodulatory potential. This potential was previously found to either enhance or suppress the desired anti-tumor DC functionality when used at different phases of their ex vivo production. In this work, we show that LL-37 can be implemented during the whole process of DC production in a way that allows LL-37 to enhance the anti-tumor functionality of produced DCs. We found that the supplementation of LL-37 during the differentiation of monocyte-derived DCs showed only a tendency to enhance their in vitro-induced lymphocyte enrichment with CD8⁺ T cells. The supplementation of LL-37 also during the process of DC antigen loading (pulsation) and maturation significantly enhanced the cell culture enrichment with CD8⁺ T cells. Moreover, this enrichment was also associated with the downregulated expression of PD-1 in CD8⁺ T cells, significantly higher frequency of tumor cell-reactive CD8⁺ T cells, and superior in vitro cytotoxicity against tumor cells. These data showed that LL-37 implementation into the whole process of the ex vivo production of DCs could significantly boost their anti-tumor performance in ACI.

Antigen targeting to dendritic cells: Still a place in future immunotherapy?

The hallmark of DCs is their potent and outstanding capacity to activate naive resting T cells. As such, DCs are the sentinels of the immune system and instrumental for the induction of immune responses. This is one of the reasons, why DCs became the focus of immunotherapeutical strategies to fight infections, cancer, and autoimmunity. Besides the exploration of adoptive DC-therapy for which DCs are generated from monocytes or purified in large numbers from the blood, alternative approaches were developed such as antigen targeting of DCs. The idea behind this strategy is that DCs resident in patients' lymphoid organs or peripheral tissues can be directly loaded with antigens in situ. The proof of principle came from mouse models; subsequent translational studies confirmed the potential of this therapy. The first clinical trials demonstrated feasibility and the induction of T-cell immunity in patients. This review will cover: (i) the historical aspects of antigen targeting, (ii) briefly summarize the biology of DCs and the immunological functions upon which this concept rests, (iii) give an overview on attempts to target DC receptors with antibodies or (glycosylated) ligands, and finally, (iv) discuss the translation of antigen targeting into clinical therapy.

Cell-Derived Vesicles for Nanoparticles' Coating: Biomimetic Approaches for Enhanced Blood Circulation and Cancer Therapy

Cancer nanomedicines are designed to encapsulate different therapeutic agents, prevent their premature release, and deliver them specifically to cancer cells, due to their ability to preferentially accumulate in tumor tissue. However, after intravenous administration, nanoparticles immediately interact with biological components that facilitate their recognition by the immune system, being rapidly removed from circulation. Reports show that less than 1% of the administered nanoparticles effectively reach the tumor site. This suboptimal pharmacokinetic profile is pointed out as one of the main factors for the nanoparticles' suboptimal therapeutic effectiveness and poor translation to the clinic. Therefore, an extended blood circulation time may be crucial to increase the nanoparticles' chances of being accumulated in the tumor and promote a site-specific delivery of therapeutic agents. For that purpose, the understanding of the forces that govern the nanoparticles' interaction with biological components and the impact of the physicochemical properties on the in vivo fate will allow the development of novel and more effective nanomedicines. Therefore, in this review, the nano-bio interactions are summarized. Moreover, the application of cell-derived vesicles for extending the blood circulation time and tumor accumulation is reviewed, focusing on the advantages and shortcomings of each cell source.

The effects of dendritic cell-based vaccines in the tumor microenvironment: Impact on myeloid-derived suppressor cells

Dendritic cells (DCs) are a heterogenous population of professional antigen presenting cells whose main role is diminished in a variety of malignancies, including cancer, leading to ineffective immune responses. Those mechanisms are inhibited due to the immunosuppressive conditions found in the tumor microenvironment (TME), where myeloid-derived suppressor cells (MDSCs), a heterogeneous population of immature myeloid cells known to play a key role in tumor immunoevasion by inhibiting T-cell responses, are extremely accumulated. In addition, it has been demonstrated that MDSCs not only suppress DC functions, but also their maturation and development within the myeloid linage. Considering that an increased number of DCs as well as the improvement in their functions boost antitumor immunity, DC-based vaccines were developed two decades ago, and promising results have been obtained throughout these years. Therefore, the remodeling of the TME promoted by DC vaccination has also been explored. Here, we aim to review the effectiveness of different DCs-based vaccines in murine models and cancer patients, either alone or synergistically combined with other treatments, being especially focused on their effect on the MDSC population.

Nanomaterials-Mediated Co-Stimulation of Toll-Like Receptors and CD40 for Antitumor Immunity

Toll-like receptors (TLRs) and CD40-related signaling pathways represent critical bridges between innate and adaptive immune responses. Here, an immunotherapy regimen that enables co-stimulation of TLR7/8- and CD40-mediated pathways is developed. TLR7/8 agonist resiquimod (R848) derived amino lipids, RAL1 and RAL2, are synthesized and formulated into RAL-derived lipid nanoparticles (RAL-LNPs). The RAL2-LNPs show efficient CD40 mRNA delivery to DCs both in vitro (90.8 ± 2.7%) and in vivo (61.3 ± 16.4%). When combined with agonistic anti-CD40 antibody, this approach can produce effective antitumor activities in mouse melanoma tumor models, thereby suppressing tumor growth, prolonging mouse survival, and establishing antitumor memory immunity. Overall, RAL2-LNPs provide a novel platform toward cancer immunotherapy by integrating innate and adaptive immunity.

Therapeutic implications of the tumor microenvironment in ovarian cancer patients receiving PD-1/PD-L1 therapy

Epithelial ovarian cancer (EOC) ranks as the second most common cause of gynecologic cancer death. The conventional treatment for patients with EOC is postoperative therapy along with platinum chemotherapy. However, a more efficient treatment regimen is of great need for these patients diagnosed with advanced disease (FIGO stages III-IV), whose survival is approximately 29%. Immunotherapy seems to be an encouraging therapeutic strategy for EOC. Given the crucial role in the complicated interactions between tumor cells and other cells, the tumor microenvironment (TME) influences the response to immunotherapy. In this review, we discuss feasible strategies for EOC immunotherapy by exploiting the reciprocity of cancer cells and the constituents of the TME.

Targeting FGL2 in glioma immunosuppression and malignant progression

Glioblastoma (GBM) is the most malignant type of glioma with the worst prognosis. Traditional therapies (surgery combined with radiotherapy and chemotherapy) have limited therapeutic effects. As a novel therapy emerging in recent years, immunotherapy is increasingly used in glioblastoma (GBM), so we expect to discover more effective immune targets. FGL2, a member of the thrombospondin family, plays an essential role in regulating the activity of immune cells and tumor cells in GBM. Elucidating the role of FGL2 in GBM can help improve immunotherapy efficacy and design treatment protocols. This review discusses the immunosuppressive role of FGL2 in the GBM tumor microenvironment and its ability to promote malignant tumor progression while considering FGL2-targeted therapeutic strategies. Also, we summarize the molecular mechanisms of FGL2 expression on various immune cell types and discuss the possibility of FGL2 and its related mechanisms as new GBM immunotherapy.

Tumor-Infiltrating Dendritic Cells: Decisive Roles in Cancer Immunosurveillance, Immunoediting, and Tumor T Cell Tolerance

The tumor microenvironment plays a key role in progression of tumorigenesis, tumor progression, and metastasis. Accumulating data reveal that dendritic cells (DCs) appear to play a key role in the development and progression of metastatic neoplasia by driving immune system dysfunction and establishing immunosuppression, which is vital for tumor evasion of host immune response. Consequently, in this review, we will discuss the function of tumor-infiltrating DCs in immune cell signaling pathways that lead to treatment resistance, tumor recurrence, and immunosuppression. We will also review DC metabolism, differentiation, and plasticity, which are essential for metastasis and the development of lung tumors. Furthermore, we will take into account the interaction between myeloid cells and DCs in tumor-related immunosuppression. We will specifically look into the molecular immune-related mechanisms in the tumor microenvironment that result in reduced drug sensitivity and tumor relapse, as well as methods for combating drug resistance and focusing on immunosuppressive tumor networks. DCs play a crucial role in modulating the immune response. Especially, as cancer progresses, DCs may switch from playing an immunostimulatory to an inhibitory role. This article’s main emphasis is on tumor-infiltrating DCs. We address how they affect tumor growth and expansion, and we highlight innovative approaches for therapeutic modulation of these immunosuppressive DCs which is necessary for future personalized therapeutic approaches.

Inducing Ectopic T Cell Clusters Using Stromal Vascular Fraction Spheroid-Based Immunotherapy to Enhance Anti-Tumor Immunity

Tertiary lymphoid structures (TLSs) provide specialized niches for immune cells, resulting in improved prognoses for patients undergoing cancer immunotherapy. Shaping TLS-like niches may improve anti-cancer immunity and overcome the current limitations of immune cell-based immunotherapy. Here, it is shown that stromal vascular fraction (SVF) from adipose tissues can enhance dendritic cell (DC)-mediated T cell immunity by inducing ectopic T lymphocyte clusters. SVF cells expanded ex vivo have phenotypes and functions similar to those of fibroblastic reticular cells in a secondary lymphoid organ, and their properties can be modulated using three-dimensional spheroid culture and coculture with DCs spiked with antigen-loaded iron oxide-zinc oxide core-shell nanoparticles. Thereby, the combination of SVF spheroids and mature DCs significantly augments T cell recruitment and retention at the injection site. This strategy elicits enhanced antigen-specific immune response and anti-tumoral immunity in mice, illustrating the potential for a novel immunotherapeutic design using SVF as a structural scaffold for TLS.

Artificial Antigen-Presenting Cell Topology Dictates T Cell Activation

Nanosized artificial antigen-presenting cells (aAPCs), synthetic immune cell mimics that aim to activate T cells ex or in vivo, offer an effective alternative to cellular immunotherapies. However, comprehensive studies that delineate the effect of nano-aAPC topology, including nanoparticle morphology and ligand density, are lacking. Here, we systematically studied the topological effects of polymersome-based aAPCs on T cell activation. We employed an aAPC library created from biodegradable poly(ethylene glycol)-block-poly(d,l-lactide) (PEG-PDLLA) polymersomes with spherical or tubular shape and variable sizes, which were functionalized with αCD3 and αCD28 antibodies at controlled densities. Our results indicate that high ligand density leads to enhancement in T cell activation, which can be further augmented by employing polymersomes with larger size. At low ligand density, the effect of both polymersome shape and size was more pronounced, showing that large elongated polymersomes better activate T cells compared to their spherical or smaller counterparts. This study demonstrates the capacity of polymersomes as aAPCs and highlights the role of topology for their rational design.

Research progress of neoantigens in gynecologic cancers

The incidence and mortality of gynecological cancers have increased over the past decade. In the absence of effective treatment strategies, many advanced patients develop resistance to conventional therapies and have poor prognosis. Neoantigens have emerged as a novel tumor-specific antigen (TSA) that arises from genomic mutations in tumor cells. With higher immunogenicity than tumor-associated antigens (TAA), they have no risk of developing autoimmune response, leading them an attractive candidate for tumor therapeutic vaccines. With the development of next-generation sequencing (NGS) technology, the identification of neoantigens has been gradually improved, and the scope of application of neoantigen vaccines has continued to expand. Combined with other therapies such as immune-checkpoint inhibitors (ICIs) or adoptive cell therapy (ACT), the application of neoantigen in gynecological cancers has extended to clinical practice. Here, we reviewed the preclinical and clinical studies of neoantigens in gynecological cancers.