Tumor microenvironment-related dendritic cell deficiency: a target to enhance tumor immunotherapy

Dopamine receptor agonist cabergoline promotes immunogenic phenotype in human monocyte-derived dendritic cells

Dendritic cells (DCs) are known as antigen-presenting cells that are capable of regulating immune responses. DCs and T cells can interact mutually to induce antigen-specific T-cell responses. Cabergoline, which is a dopamine (DA) receptor agonist, seems to implement anti-inflammatory properties in the immune system, and therefore in the present study the impact of a DA receptor agonist cabergoline on the monocyte-derived DCs (moDCs) was assessed. Immature moDCs were treated with lipopolysaccharide to produce mature DCs (mDCs). The expression of DCs' related surface markers namely: CD11c, HLA-DR, and CD86 was measured by utilizing of flow cytometry. Real-time PCR was the technique of choice to determine the levels at which diverse inflammatory and anti-inflammatory factors in cabergoline-treated and control mDC groups were expressed. DCs treated with cabergoline displayed a significant decrease in CD86 and HLA-DR expression, markers linked to maturation and antigen presentation, respectively. In addition, the cabergoline-mDC group showed a considerable decline in terms of the levels at which IL-10, TGF-β, and IDO genes were expressed, and an increase in the expression of TNF-α and IL-12 in comparison to the mDC control group. Our findings revealed that cabergoline as an immunomodulatory agent can relatively shift DCs into an immunogenic state, and there is a requirement for further investigations to evaluate the effects of cabergoline-treated DCs on the T cell responses in vitro, and also in various diseases including cancer in animal models.

Exploring Immune Redox Modulation in Bacterial Infections: Insights into Thioredoxin-Mediated Interactions and Implications for Understanding Host-Pathogen Dynamics

Bacterial infections trigger a multifaceted interplay between inflammatory mediators and redox regulation. Recently, accumulating evidence has shown that redox signaling plays a significant role in immune initiation and subsequent immune cell functions. This review addresses the crucial role of the thioredoxin (Trx) system in the initiation of immune reactions and regulation of inflammatory responses during bacterial infections. Downstream signaling pathways in various immune cells involve thiol-dependent redox regulation, highlighting the pivotal roles of thiol redox systems in defense mechanisms. Conversely, the survival and virulence of pathogenic bacteria are enhanced by their ability to counteract oxidative stress and immune attacks. This is achieved through the reduction of oxidized proteins and the modulation of redox-sensitive signaling pathways, which are functions of the Trx system, thereby fortifying bacterial resistance. Moreover, some selenium/sulfur-containing compounds could potentially be developed into targeted therapeutic interventions for pathogenic bacteria. Taken together, the Trx system is a key player in redox regulation during bacterial infection, and contributes to host-pathogen interactions, offering valuable insights for future research and therapeutic development.

Differentiation, maturation, and collection of THP-1-derived dendritic cells based on a PEG hydrogel culture platform

PURPOSE

Dendritic cell (DC) is a spearhead responsible for immune response and surrounded by extracellular matrix in three-dimensional (3D) tissue. Nevertheless, conventional DC culture has relied on suspension or two-dimensional (2D) tissue culture plate (TCP)-based culture system. This culture condition often fails to recapitulate the physiological behavior of DC in real tissue. In this work, the effect of culture condition on DC physiology was explored with varying 3D hydrogel property (i.e., degradability, adhesion, and stiffness). In particular, DC differentiation and maturation in 3D were evaluated comparing the conventional TCP-based culture condition.

METHOD

THP-1 cells were encapsulated in poly(ethylene glycol) (PEG) hydrogel via thiol-ene photocrosslinking with non-degradable or proteolytically degradable peptide crosslinker. Hydrogel stiffness was manipulated by controlling the concentration of crosslinker. The metabolic activities and cytotoxicity of the encapsulated cells were measured by resazurin and Live/Dead assays, respectively. Cell harvesting was conducted via enzymatic degradation using α-chymotrypsin, and differentiation and maturation of the liberated DCs were evaluated by quantitative polymerase chain reaction and flow cytometry.

RESULTS

THP-1 cells well proliferated in the soft degradable hydrogel with a higher metabolic activity. However, the stiff matrix inhibited cell growth in 3D. The gene expression assay indicated that the 3D hydrogel condition was superior to 2D culture in terms of differentiation and maturation of DC. Interestingly, the stiffness of matrix was important factor in DC function. In the stiff hydrogel, the expression levels of differentiation and maturation markers were higher compared to the low stiffness hydrogel. The mature DCs caged in the hydrogel matrix were harvested after short enzymatic digestion of hydrogel and the liberated cells had over 90% viability. The flow cytometric result revealed that the proportion of CD80 + /CD86 + cells from the stiff hydrogel was relatively higher than cells either from 2D or soft hydrogel in 3D.

CONCLUSION

The collected evidence indicated that the proteolytically degradable PEG hydrogel matrix promoted DC differentiation and maturation. In addition, the matrix stiffness control could manipulate the marker expressions of differentiation and maturation. Particularly, the mature DC was successfully collected from the hydrogel matrix. These results highlighted the PEG hydrogel-based DC culture might be a useful tool for potential DC-based immunotherapies.

cGAS-STING pathway mediates activation of dendritic cell sensing of immunogenic tumors

Type I interferons (IFN-I) play pivotal roles in tumor therapy for three decades, underscoring the critical importance of maintaining the integrity of the IFN-1 signaling pathway in radiotherapy, chemotherapy, targeted therapy, and immunotherapy. However, the specific mechanism by which IFN-I contributes to these therapies, particularly in terms of activating dendritic cells (DCs), remains unclear. Based on recent studies, aberrant DNA in the cytoplasm activates the cyclic GMP-AMP synthase (cGAS)- stimulator of interferon genes (STING) signaling pathway, which in turn produces IFN-I, which is essential for antiviral and anticancer immunity. Notably, STING can also enhance anticancer immunity by promoting autophagy, inflammation, and glycolysis in an IFN-I-independent manner. These research advancements contribute to our comprehension of the distinctions between IFN-I drugs and STING agonists in the context of oncology therapy and shed light on the challenges involved in developing STING agonist drugs. Thus, we aimed to summarize the novel mechanisms underlying cGAS-STING-IFN-I signal activation in DC-mediated antigen presentation and its role in the cancer immune cycle in this review.

Cellular interactions in tumor microenvironment during breast cancer progression: new frontiers and implications for novel therapeutics

The breast cancer tumor microenvironment (TME) is dynamic, with various immune and non-immune cells interacting to regulate tumor progression and anti-tumor immunity. It is now evident that the cells within the TME significantly contribute to breast cancer progression and resistance to various conventional and newly developed anti-tumor therapies. Both immune and non-immune cells in the TME play critical roles in tumor onset, uncontrolled proliferation, metastasis, immune evasion, and resistance to anti-tumor therapies. Consequently, molecular and cellular components of breast TME have emerged as promising therapeutic targets for developing novel treatments. The breast TME primarily comprises cancer cells, stromal cells, vasculature, and infiltrating immune cells. Currently, numerous clinical trials targeting specific TME components of breast cancer are underway. However, the complexity of the TME and its impact on the evasion of anti-tumor immunity necessitate further research to develop novel and improved breast cancer therapies. The multifaceted nature of breast TME cells arises from their phenotypic and functional plasticity, which endows them with both pro and anti-tumor roles during tumor progression. In this review, we discuss current understanding and recent advances in the pro and anti-tumoral functions of TME cells and their implications for developing safe and effective therapies to control breast cancer progress.

Ferroptosis in cancer: From molecular mechanisms to therapeutic strategies

Ferroptosis is a non-apoptotic form of regulated cell death characterized by the lethal accumulation of iron-dependent membrane-localized lipid peroxides. It acts as an innate tumor suppressor mechanism and participates in the biological processes of tumors. Intriguingly, mesenchymal and dedifferentiated cancer cells, which are usually resistant to apoptosis and traditional therapies, are exquisitely vulnerable to ferroptosis, further underscoring its potential as a treatment approach for cancers, especially for refractory cancers. However, the impact of ferroptosis on cancer extends beyond its direct cytotoxic effect on tumor cells. Ferroptosis induction not only inhibits cancer but also promotes cancer development due to its potential negative impact on anticancer immunity. Thus, a comprehensive understanding of the role of ferroptosis in cancer is crucial for the successful translation of ferroptosis therapy from the laboratory to clinical applications. In this review, we provide an overview of the recent advancements in understanding ferroptosis in cancer, covering molecular mechanisms, biological functions, regulatory pathways, and interactions with the tumor microenvironment. We also summarize the potential applications of ferroptosis induction in immunotherapy, radiotherapy, and systemic therapy, as well as ferroptosis inhibition for cancer treatment in various conditions. We finally discuss ferroptosis markers, the current challenges and future directions of ferroptosis in the treatment of cancer.

Antitumor immunostimulatory activity of the traditional Chinese medicine polysaccharide on hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a prevalent malignancy, often associated with compromised immune function in affected patients. This can be attributed to the secretion of specific factors by liver cancer cells, which hinder the immune response and lead to a state of immune suppression. Polysaccharides derived from traditional Chinese medicine (TCM) are valuable constituents known for their immunomodulatory properties. This review aims to look into the immunomodulatory effects of TCM polysaccharides on HCC. The immunomodulatory effects of TCM polysaccharides are primarily manifested through the activation of effector T lymphocytes, dendritic cells, NK cells, and macrophages against hepatocellular carcinoma (HCC) both in vivo and in vitro settings. Furthermore, TCM polysaccharides have demonstrated remarkable adjuvant antitumor immunomodulatory effects on HCC in clinical settings. Therefore, the utilization of TCM polysaccharides holds promising potential for the development of novel therapeutic agents or adjuvants with advantageous immunomodulatory properties for HCC.

Nanomaterial-encapsulated STING agonists for immune modulation in cancer therapy

The cGAS-STING signaling pathway has emerged as a critical mediator of innate immune responses, playing a crucial role in improving antitumor immunity through immune effector responses. Targeting the cGAS-STING pathway holds promise for overcoming immunosuppressive tumor microenvironments (TME) and promoting effective tumor elimination. However, systemic administration of current STING agonists faces challenges related to low bioavailability and potential adverse effects, thus limiting their clinical applicability. Recently, nanotechnology-based strategies have been developed to modulate TMEs for robust immunotherapeutic responses. The encapsulation and delivery of STING agonists within nanoparticles (STING-NPs) present an attractive avenue for antitumor immunotherapy. This review explores a range of nanoparticles designed to encapsulate STING agonists, highlighting their benefits, including favorable biocompatibility, improved tumor penetration, and efficient intracellular delivery of STING agonists. The review also summarizes the immunomodulatory impacts of STING-NPs on the TME, including enhanced secretion of pro-inflammatory cytokines and chemokines, dendritic cell activation, cytotoxic T cell priming, macrophage re-education, and vasculature normalization. Furthermore, the review offers insights into co-delivered nanoplatforms involving STING agonists alongside antitumor agents such as chemotherapeutic compounds, immune checkpoint inhibitors, antigen peptides, and other immune adjuvants. These platforms demonstrate remarkable versatility in inducing immunogenic responses within the TME, ultimately amplifying the potential for antitumor 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.

The DC-T cell axis is an effective target for the treatment of non-small cell lung cancer

The dendritic cell (DC)-T cell axis is a bridge that connects innate and adaptive immunities. The initial immune response against tumors is mainly induced by mature antigen-presenting DCs. Enhancing the crosstalk between DCs and T cells may be an effective approach to improve the immune response to non-small cell lung cancer (NSCLC). In this article, a review was made of the interaction between DCs and T cells in the treatment of NSCLC and how this interaction affects the treatment outcome.

Research progress of nanovaccine in anti-tumor immunotherapy

Tumor vaccines aim to activate dormant or unresponsive tumor-specific T lymphocytes by using tumor-specific or tumor-associated antigens, thus enhancing the body's natural defense against cancer. However, the effectiveness of tumor vaccines is limited by the presence of tumor heterogeneity, low immunogenicity, and immune evasion mechanisms. Fortunately, multifunctional nanoparticles offer a unique chance to address these issues. With the advantages of their small size, high stability, efficient drug delivery, and controlled surface chemistry, nanomaterials can precisely target tumor sites, improve the delivery of tumor antigens and immune adjuvants, reshape the immunosuppressive tumor microenvironment, and enhance the body's anti-tumor immune response, resulting in improved efficacy and reduced side effects. Nanovaccine, a type of vaccine that uses nanotechnology to deliver antigens and adjuvants to immune cells, has emerged as a promising strategy for cancer immunotherapy due to its ability to stimulate immune responses and induce tumor-specific immunity. In this review, we discussed the compositions and types of nanovaccine, and the mechanisms behind their anti-tumor effects based on the latest research. We hope that this will provide a more scientific basis for designing tumor vaccines and enhancing the effectiveness of tumor immunotherapy.

Impaired function of dendritic cells within the tumor microenvironment

Dendritic cells (DCs), a class of professional antigen-presenting cells, are considered key factors in the initiation and maintenance of anti-tumor immunity due to their powerful ability to present antigen and stimulate T-cell responses. The important role of DCs in controlling tumor growth and mediating potent anti-tumor immunity has been demonstrated in various cancer models. Accordingly, the infiltration of stimulatory DCs positively correlates with the prognosis and response to immunotherapy in a variety of solid tumors. However, accumulating evidence indicates that DCs exhibit a significantly dysfunctional state, ultimately leading to an impaired anti-tumor immune response due to the effects of the immunosuppressive tumor microenvironment (TME). Currently, numerous preclinical and clinical studies are exploring immunotherapeutic strategies to better control tumors by restoring or enhancing the activity of DCs in tumors, such as the popular DC-based vaccines. In this review, an overview of the role of DCs in controlling tumor progression is provided, followed by a summary of the current advances in understanding the mechanisms by which the TME affects the normal function of DCs, and concluding with a brief discussion of current strategies for DC-based tumor immunotherapy.

Therapies Targeting Immune Cells in Tumor Microenvironment for Non-Small Cell Lung Cancer

The tumor microenvironment (TME) plays critical roles in immune modulation and tumor malignancies in the process of cancer development. Immune cells constitute a significant component of the TME and influence the migration and metastasis of tumor cells. Recently, a number of therapeutic approaches targeting immune cells have proven promising and have already been used to treat different types of cancer. In particular, PD-1 and PD-L1 inhibitors have been used in the first-line setting in non-small cell lung cancer (NSCLC) with PD-L1 expression ≥1%, as approved by the FDA. In this review, we provide an introduction to the immune cells in the TME and their efficacies, and then we discuss current immunotherapies in NSCLC and scientific research progress in this field.

ROS fine-tunes the function and fate of immune cells

The redox state is essential to the process of cell life, which determines cell fate. As an important signaling molecule of the redox state, reactive oxygen species (ROS) are crucial for the homeostasis of immune cells and participate in the pathological processes of different diseases. We discuss the underlying mechanisms and possible signaling pathways of ROS to fine-tune the proliferation, differentiation, polarization and function of immune cells, including T cells, B cells, neutrophils, macrophages, myeloid-derived inhibitory cells (MDSCs) and dendritic cells (DCs). We further emphasize how excessive ROS lead to programmed immune cell death such as apoptosis, ferroptosis, pyroptosis, NETosis and necroptosis, providing valuable insights for future therapeutic strategies in human diseases.

Tumor microenvironment signaling and therapeutics in cancer progression

Tumor development and metastasis are facilitated by the complex interactions between cancer cells and their microenvironment, which comprises stromal cells and extracellular matrix (ECM) components, among other factors. Stromal cells can adopt new phenotypes to promote tumor cell invasion. A deep understanding of the signaling pathways involved in cell-to-cell and cell-to-ECM interactions is needed to design effective intervention strategies that might interrupt these interactions. In this review, we describe the tumor microenvironment (TME) components and associated therapeutics. We discuss the clinical advances in the prevalent and newly discovered signaling pathways in the TME, the immune checkpoints and immunosuppressive chemokines, and currently used inhibitors targeting these pathways. These include both intrinsic and non-autonomous tumor cell signaling pathways in the TME: protein kinase C (PKC) signaling, Notch, and transforming growth factor (TGF-β) signaling, Endoplasmic Reticulum (ER) stress response, lactate signaling, Metabolic reprogramming, cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) and Siglec signaling pathways. We also discuss the recent advances in Programmed Cell Death Protein 1 (PD-1), Cytotoxic T-Lymphocyte Associated Protein 4 (CTLA4), T-cell immunoglobulin mucin-3 (TIM-3) and Lymphocyte Activating Gene 3 (LAG3) immune checkpoint inhibitors along with the C-C chemokine receptor 4 (CCR4)- C-C class chemokines 22 (CCL22)/ and 17 (CCL17), C-C chemokine receptor type 2 (CCR2)- chemokine (C-C motif) ligand 2 (CCL2), C-C chemokine receptor type 5 (CCR5)- chemokine (C-C motif) ligand 3 (CCL3) chemokine signaling axis in the TME. In addition, this review provides a holistic understanding of the TME as we discuss the three-dimensional and microfluidic models of the TME, which are believed to recapitulate the original characteristics of the patient tumor and hence may be used as a platform to study new mechanisms and screen for various anti-cancer therapies. We further discuss the systemic influences of gut microbiota in TME reprogramming and treatment response. Overall, this review provides a comprehensive analysis of the diverse and most critical signaling pathways in the TME, highlighting the associated newest and critical preclinical and clinical studies along with their underlying biology. We highlight the importance of the most recent technologies of microfluidics and lab-on-chip models for TME research and also present an overview of extrinsic factors, such as the inhabitant human microbiome, which have the potential to modulate TME biology and drug responses.

T7 peptide-decorated exosome-based nanocarrier system for delivery of Galectin-9 siRNA to stimulate macrophage repolarization in glioblastoma

PURPOSE

Exosomes are nano-vesicular carriers capable of delivering cargoes for intercellular communication, which holds potential as biocompatible and high efficiency systems for drug delivery. In this study, we evaluated the potential effect of T7 peptide-decorated exosome-loaded Galectin-9 siRNA (T7-Exo/siGalectin-9) in the M1 polarization of macrophages and immunosuppression of glioblastoma (GBM).

METHODS

Differentially expressed genes in GBM were in silico predicted and then experimentally verified. Galectin-9 was knocked down by siRNA to assess its role in tumor-bearing mice. T7 peptide-decorated exosomes (derived from human embryonic kidney [HEK]-293T cells) targeting GBM were prepared, and loaded with Galectin-9 siRNA by electroporation to prepare nanoformulations (T7-Exo/siGalectin-9). The role of T7-Exo/siGalectin-9 in CD8+ T cell cytotoxicity to target GBM cells and polarization of macrophages was evaluated after artificial modulation of Galectin-9 expression. Anti-tumor effects of T7-Exo/siGalectin-9 were elucidated in vitro and in vivo.

RESULTS

Galectin-9 was highly expressed in GBM tissues and cell lines. The siRNA-mediated knockdown of Galectin-9 repressed the growth of xenografts of GBM cells in C57BL/6 mice and activated immune response in the tumor microenvironment. T7-Exo/siGalectin-9 effectively delivered siGalectin-9 to GBM cells. T7-Exo/siGalectin-9 contributed to activation of the TLR7-IRF5 pathway, which polarized macrophages to M1 phenotype. By this mechanism, phagocytosis of GBM cells by macrophages was increased, the anti-tumor effect of CD8+ T cells was enhanced and the inflammatory responses were suppressed.

CONCLUSION

Overall, T7-Exo/siGalectin-9 promotes macrophage repolarization and restricts the immunosuppression of GBM, thus providing novel insights into and drug delivery system of immunotherapy for GBM.

Human γδ T cells induce CD8+ T cell antitumor responses via antigen-presenting effect through HSP90-MyD88-mediated activation of JNK

Human Vγ9Vδ2 T cells have attracted considerable attention as novel alternative antigen-presenting cells (APCs) with the potential to replace dendritic cells in antitumor immunotherapy owing to their high proliferative capacity and low cost. However, the utility of γδ T cells as APCs to induce CD8⁺ T cell-mediated antitumor immune response, as well as the mechanism by which they perform APC functions, remains unexplored. In this study, we found that activated Vγ9Vδ2 T cells were capable of inducing robust CD8⁺ T cell responses in osteosarcoma cells. Activated γδ T cells also effectively suppressed osteosarcoma growth by priming CD8⁺ T cells in xenograft animal models. Mechanistically, we further revealed that activated γδ T cells exhibited increased HSP90 production, which fed back to upregulate MyD88, followed by JNK activation and a subsequent improvement in CCL5 secretion, leading to enhanced CD8⁺ T cell cross-priming. Thus, our study suggests that Vγ9Vδ2 T cells represent a promising alternative APC for the development of γδ T cell-based tumor immunotherapy.

Virus-like Particles for TEM Regulation and Antitumor Therapy

Tumor development and metastasis are intimately associated with the tumor microenvironment (TME), and it is difficult for vector-restricted drugs to act on the TME for long-term cancer immunotherapy. Virus-like particles (VLPs) are nanocage structures self-assembled from nucleic acid free viral proteins. Most VLPs range from 20-200 nm in diameter and can naturally drain into lymph nodes to induce robust humoral immunity. As natural nucleic acid nanocarriers, their surfaces can also be genetically or chemically modified to achieve functions such as TME targeting. This review focuses on the design ideas of VLP as nanocarriers and the progress of their research in regulating TME.

A Machine Learning Workflow of Multiplexed Immunofluorescence Images to Interrogate Activator and Tolerogenic Profiles of Conventional Type 1 Dendritic Cells Infiltrating Melanomas of Disease-Free and Metastatic Patients

Melanoma is the deadliest form of skin cancer. Due to its high mutation rates, melanoma is a convenient model to study antitumor immune responses. Dendritic cells (DCs) play a key role in activating cytotoxic CD8⁺ T lymphocytes and directing them to kill tumor cells. Although there is evidence that DCs infiltrate melanomas, information about the profile of these cells, their activity states, and potential antitumor function remains unclear, particularly for conventional DCs type 1 (cDC1). Approaches to profiling tumor-infiltrating DCs are hindered by their diversity and the high number of signals that can affect their state of activation. Multiplexed immunofluorescence (mIF) allows the simultaneous analysis of multiple markers, but image-based analysis is time-consuming and often inconsistent among analysts. In this work, we evaluated several machine learning (ML) algorithms and established a workflow of nine-parameter image analysis that allowed us to study cDC1s in a reproducible and accessible manner. Using this workflow, we compared melanoma samples between disease-free and metastatic patients at diagnosis. We observed that cDC1s are more abundant in the tumor infiltrate of the former. Furthermore, cDC1s in disease-free patients exhibit an expression profile more congruent with an activator function: CD40^highPD-L1^low CD86⁺IL-12⁺. Although disease-free patients were also enriched with CD40⁻PD-L1⁺ cDC1s, these cells were also more compatible with an activator phenotype. The opposite was true for metastatic patients at diagnosis who were enriched for cDC1s with a more tolerogenic phenotype (CD40^lowPD-L1^highCD86⁻IL-12⁻IDO⁺). ML-based workflows like the one developed here can be used to analyze complex phenotypes of other immune cells and can be brought to laboratories with standard expertise and computer capacity.

Integrated Bioinformatics and Experimental Analysis Identified TRIM28 a Potential Prognostic Biomarker and Correlated with Immune Infiltrates in Liver Hepatocellular Carcinoma

Background

Since the 1970s, liver hepatocellular carcinoma (LIHC) has experienced a constant rise in incidence and mortality rates, making the identification of LIHC biomarkers very important. Tripartite Motif-Containing 28 (TRIM28) is a protein-coding gene which encodes the tripartite motif-containing proteins (TRIMs) family and is associated with specific chromatin regions. TRIM28 expression and its prognostic value and impact on the immune system in LIHC patients are being investigated for the first time.

Methods

The TRIM28 expression data from TCGA database was used to analyze TRIM28 expression, clinicopathological information, gene enrichment, and immune infiltration and conduct additional bioinformatics analysis. R language was used for statistical analysis. TIMER, CIBERSORT, and ssGSEA were used to assess immune responses of TRIM28 in LIHC. Next, the results were validated using GEPIA, ROC analysis, and immunohistochemical staining pictures from the THPA. GSE14520, GSE63898, and GSE87630 datasets were analyzed using ROC analysis to further evaluate TRIM28's diagnostic value. To ultimately determine TRIM28 expression, we performed qRT-PCR (quantitative real-time polymerase chain reaction).

Results

High TRIM28 expression level was associated with T classification, pathologic stage, histologic grade, and serum AFP levels. In patients with LIHC, TRIM28 was an independent risk factor for a poor prognosis. The pathways ligand-receptor interaction, which is critical in LIHC patients, were closely associated with TRIM28 expression, and the function of DC could be suppressed by overexpression of TRIM28. As a final step, our results were validated by GEO data and qRT-PCR.

Conclusions

TRIM28 will shed new light on LIHC mechanisms. As an effective diagnostic and intervention tool, this gene will be able to diagnose and treat LIHC at an early stage.

Dendritic Cells: The Long and Evolving Road towards Successful Targetability in Cancer

Dendritic cells (DCs) are a unique myeloid cell lineage that play a central role in the priming of the adaptive immune response. As such, they are an attractive target for immune oncology based therapeutic approaches. However, targeting these cells has proven challenging with many studies proving inconclusive or of no benefit in a clinical trial setting. In this review, we highlight the known and unknown about this rare but powerful immune cell. As technologies have expanded our understanding of the complexity of DC development, subsets and response features, we are now left to apply this knowledge to the design of new therapeutic strategies in cancer. We propose that utilization of these technologies through a multiomics approach will allow for an improved directed targeting of DCs in a clinical trial setting. In addition, the DC research community should consider a consensus on subset nomenclature to distinguish new subsets from functional or phenotypic changes in response to their environment.

Plasmacytoid Dendritic Cells as a Novel Cell-Based Cancer Immunotherapy

Plasmacytoid dendritic cells (pDCs) are multifaceted immune cells with a wide range of innate and adaptive immunological functions. They constitute the first line of defence against multiple viral infections and have also been reported to actively participate in antitumor immune responses. The clinical implication of the presence of pDCs in the tumor microenvironment (TME) is still ambiguous, but it is clear that pDCs possess the ability to modulate tumor-specific T cell responses and direct cytotoxic functions. Therapeutic strategies designed to exploit these qualities of pDCs to boost tumor-specific immune responses could represent an attractive alternative compared to conventional therapeutic approaches in the future, and promising antitumor effects have already been reported in phase I/II clinical trials. Here, we review the many roles of pDCs in cancer and present current advances in developing pDC-based immunotherapeutic approaches for treating cancer.

CTLA-4 silencing in dendritic cells loaded with colorectal cancer cell lysate improves autologous T cell responses in vitro

Dendritic cell (DC)-based immunotherapy has increased interest among anti-cancer immunotherapies. Nevertheless, the immunosuppressive mechanisms in the tumor milieu, e.g., inhibitory immune checkpoint molecules, have been implicated in diminishing the efficacy of DC-mediated anti-tumoral immune responses. Therefore, the main challenge is to overcome inhibitory immune checkpoint molecules and provoke efficient T-cell responses to antigens specifically expressed by cancerous cells. Among the inhibitory immune checkpoints, cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) expression on DCs diminishes their maturation and antigen presentation capability. Accordingly, we hypothesized that the expression of CTLA-4 on DCs inhibits the T cell-mediated anti-tumoral responses generated following the presentation of tumor antigens by DCs to T lymphocytes. In this study, we loaded colorectal cancer (CRC) cell lysate on DCs and inhibited the expression of CTLA-4 by small interfering RNA (siRNA) in them to investigate the DCs’ functional and phenotypical features, and T-cell mediated responses following DC/T cell co-culture. Our results demonstrated that blockade of CTLA-4 could promote stimulatory properties of DCs. In addition, CTLA-4 silenced CRC cell lysate-loaded DCs compared to the DCs without CTLA-4 silencing resulted in augmented T cell proliferation and cytokine production, i.e., IFN-γ and IL-4. Taken together, our findings suggest CTLA-4 silenced CRC cell lysate-loaded DCs as a promising therapeutic approach however further studies are needed before this strategy can be used in clinical practice.

ER-Targeting PDT Converts Tumors into In Situ Therapeutic Tumor Vaccines

A therapeutic tumor vaccine is a promising approach to cancer treatment. One of its strategies is to treat patient-derived tumor cells in vitro and then administer them in vivo to induce an adaptive immune response and achieve cancer treatment. Here, we want to explore the possibility of converting cancer tissue into a therapeutic tumor vaccine through induced immunogenic cell death (ICD) in situ. We loaded indocyanine green (ICG) into liposomes (ICG-Lipo) and modified it with the pardaxin peptide to realize an endoplasmic reticulum (ER)-targeting function (Par-ICG-Lipo). A microfluidic technique was developed for loading ICG, a water-soluble molecule, into liposomes with a high encapsulation efficiency (greater than 90%). Under near-infrared (NIR) irradiation, ER-targeting photodynamic therapy (PDT) induced by Par-ICG-Lipo could promote the release of danger-signaling molecules (DAMPs) and tumor antigens (TAAs) in vivo, which significantly enhanced the immunogenicity in vivo and thus stimulates a strong antitumor immune response. This process would be further amplified by adopting dendritic cells. In general, our strategy transformed in situ tumor cells into therapeutic vaccines by ER-targeting PDT, which could provide a clinically applicable and effective approach for cancer treatment.

A Prognosis Marker Dynein Cytoplasmic 1 Heavy Chain 1 Correlates with EMT and Immune Signature in Liver Hepatocellular Carcinoma by Bioinformatics and Experimental Analysis

Background

Liver hepatocellular carcinoma (LIHC) has had a continuous increase in incidence and mortality rates over the last 40 years. Dynein Cytoplasmic 1 Heavy Chain 1 (DYNC1H1) is a protein coding gene which encodes the cytoplasmic dynein heavy chain family. This is the first investigation into the expression of DYNC1H1 and its mechanisms of action in LIHC patients.

Methods

Based on the DYNC1H1 expression data from the TCGA database, we performed the DYNC1H1 expression, clinicopathological data, gene enrichment, and immune infiltration analysis. TIMER and CIBERSORT were used to assess immune responses of DYNC1H1 in LIHC. GEPIA, K-M survival analysis, and immunohistochemical staining pictures from the THPA were used to validate the results. In order to evaluate the diagnostic value of DYNC1H1, GEO datasets were analyzed by using ROC analysis. And quantitative real-time polymerase chain reaction was also carried out to evaluate the expression of DYNC1H1.

Results

DYNC1H1 expression levels were associated with T classification, pathologic stage, histologic grade, and serum AFP levels. DYNC1H1 is an independent factor for a poor prognosis in patients with LIHC. Further study showed that high expression of DYNC1H1 was enriched in epithelial–mesenchymal transition (EMT) and the TGF β signaling pathway by GSEA analysis enrichment, indicating that DYNC1H1 might play a key role in the progression of CRC through EMT and immune response, which also had been validated by the experimental assays.

Conclusions

DYNC1H1 will provide a novel and important perspective for the mechanisms of LIHC by regulating EMT. This gene will be able to act as an efficacious tool for the early diagnosis and effective intervention of LIHC.

CTHRC1 is a prognosis-related biomarker correlated with immune infiltrates in colon adenocarcinoma

Background

Colon adenocarcinoma (COAD) is one of the common cancers worldwide. Collagen triple helix repeat containing 1 (CTHRC1) has been reported to be involved in cell invasion, angiogenesis, and the promotion of epithelial-mesenchymal transformation by mediating multiple signaling pathways. However, the role of CTHRC1 in COAD has not yet been determined.

Methods

Differentially expressed genes were evaluated using gene expression data from the Oncomine and TIMER databases. Correlations between CTHRC1 gene expression and clinicopathological factors were analyzed using gene expression data from UALCAN databases. Then, we searched the GEPIA database to evaluate the association of CTHRC1 gene expression with clinical outcomes. The cBioPortal database was used to analyze CTHRC1 genetic alterations. Subsequently, the TIMER website was chosen to assess the correlation of CTHRC1 with the tumor immune cell infiltration level. The TCGA dataset was used for a gene set enrichment analysis (GSEA).

Result

CTHRC1 was highly expressed in COAD patients, and significantly related to poor prognosis. In addition, elevated expression of CTHRC1 was related to the clinical stage and pathological type of COAD. The GSEA analysis showed that CTHRC1 was enriched in Gα signaling, GCPR ligand binding, neutrophil degranulation, interleukin signaling, and tumor-associated pathways. In addition, CTHRC1 was significantly associated with the expression of multiple immune markers related to specific immune cells.

Conclusion

This study suggest that CTHRC1 expression is related to the prognosis and immune infiltration of COAD patients. Therefore, CTHRC1 may be a new candidate prognostic biomarker for determining immune infiltration levels and providing COAD prognoses.

Dendritic cell-based cancer immunotherapy in the era of immune checkpoint inhibitors: From bench to bedside

Dendritic cells (DCs) can present tumoral antigens to T-cells and stimulate T-cell-mediated anti-tumoral immune responses. In addition to uptaking, processing, and presenting tumoral antigens to T-cells, co-stimulatory signals have to be established between DCs with T-cells to develop anti-tumoral immune responses. However, most of the tumor-infiltrated immune cells are immunosuppressive in the tumor microenvironment (TME), paving the way for immune evasion of tumor cells. This immunosuppressive TME has also been implicated in suppressing the DC-mediated anti-tumoral immune responses, as well. Various factors, i.e., immunoregulatory cells, metabolic factors, tumor-derived immunosuppressive factors, and inhibitory immune checkpoint molecules, have been implicated in developing the immunosuppressive TME. Herein, we aimed to review the biology of DCs in developing T-cell-mediated anti-tumoral immune responses, the significance of immunoregulatory cells in the TME, metabolic barriers contributing to DCs dysfunction in the TME, tumor-derived immunosuppressive factors, and inhibitory immune checkpoint molecules in DC-based cell therapy outcomes. With reviewing the ongoing clinical trials, we also proposed a novel therapeutic strategy to increase the efficacy of DC-based cell therapy. Indeed, the combination of DC-based cell therapy with monoclonal antibodies against novel immune checkpoint molecules can be a promising strategy to increase the response rate of patients with cancers.

Friends with Benefits: Chemokines, Glioblastoma-Associated Microglia/Macrophages, and Tumor Microenvironment

Glioma is the most common primary intracranial tumor and has the greatest prevalence of all brain tumors. Treatment resistance and tumor recurrence in GBM are mostly explained by considerable alterations within the tumor microenvironment, as well as extraordinary cellular and molecular heterogeneity. Soluble factors, extracellular matrix components, tissue-resident cell types, resident or newly recruited immune cells together make up the GBM microenvironment. Regardless of many immune cells, a profound state of tumor immunosuppression is supported and developed, posing a considerable hurdle to cancer cells' immune-mediated destruction. Several studies have suggested that various GBM subtypes present different modifications in their microenvironment, although the importance of the microenvironment in treatment response has yet to be determined. Understanding the microenvironment and how it changes after therapies is critical because it can influence the remaining invasive GSCs and lead to recurrence. This review article sheds light on the various components of the GBM microenvironment and their roles in tumoral development, as well as immune-related biological processes that support the interconnection/interrelationship between different cell types. Also, we summarize the current understanding of the modulation of soluble factors and highlight the dysregulated inflammatory chemokine/specific receptors cascades/networks and their significance in tumorigenesis, cancer-related inflammation, and metastasis.

Glutamine Metabolism-Regulated Nanoparticles to Enhance Chemoimmunotherapy by Increasing Antigen Presentation Efficiency

Although the strategies to induce dendritic cells (DCs) maturation and promote their antigen presentation can stimulate the tumor immune response, the endogenous deficiency and immunosuppression of DCs reduce antigen utilization, which limits antigen presentation efficiency and reduces immunotherapy effectiveness. Here, we report an endogenous stimulus-responsive nanodelivery system (DOX@HFn-MSO@PGZL). On the one hand, doxorubicin (DOX) promoted antigen presentation by DCs after the immunogenic death of tumor cells. On the other hand, l-methionine sulfoximine (MSO) regulated the glutamine metabolism of tumor-associated macrophages (TAMs) to induce a shift toward the M1-type. M1-TAMs synergistically presented antigens with mature DCs and were more frequently produced to destroy the tumor suppressive immune microenvironment, resulting in the alleviation of DCs functional inhibition. Ultimately, the antigen presentation efficiency was improved, completely activating tumor immunity and exhibiting powerful antitumor effects.

Efficient Delivery of Antibodies Intracellularly by Co-Assembly with Hexahistidine-Metal Assemblies (HmA)

PURPOSE

There has been a substantial global market for antibodies, which are based on extracellular targets. Binding intracellular targets by antibodies will bring new chances in antibody therapeutics and a huge market increase. We aim to evaluate the efficiency of a novel delivery system of His6-metal assembly (HmA) in delivering intracellular antibodies and biofunctions of delivered antibodies.

METHODS

In this study, the physicochemical properties of HmA@Antibodies generated through co-assembling with antibodies and HmA were well characterized by dynamic light scatter. The cytotoxicity of HmA@Antibodies was investigated by Cell Counting Kit-8 (CCK-8). The endocytic kinetics and lysosome escape process of HmA@Antibodies were studied by flow cytometry and fluorescent staining imaging, respectively. Compared to the commercialized positive control, the intracellular delivery efficiency by HmA@Antibodies and biofunctions of delivered antibodies were evaluated by fluorescent imaging and CCK-8.

RESULTS

Various antibodies (IgG, anti-β-tubulin and anti-NPC) could co-assemble with HmA under a gentle condition, producing nano-sized (~150 nm) and positively charged (~+30 eV) HmA@Antibodies particles with narrow size distribution (PDI ~ 0.15). HmA displayed very low cytotoxicity to divers cells (DCs, HeLa, HCECs, and HRPE) even after 96 h for the feeding concentration ≤100 μg mL-1, and fast escape from endosomes. In the case of delivery IgG, the delivery efficiency into alive cells of HmA was better than a commercial protein delivery reagent (PULSin). For cases of the anti-β-tubulin and anti-NPC, HmA showed comparable delivery efficiency to their positive controls, but HmA with ability to deliver these antibodies into alive cells was still superior to positive controls delivering antibodies into dead cells through punching holes.

CONCLUSION

Our results indicate that this strategy is a feasible way to deliver various antibodies intracellularly while preserving their functions, which has great potential in various applications and treating many refractory diseases by intracellular antibody delivery.

Advances of Tumorigenesis, Diagnosis at Early Stage, and Cellular Immunotherapy in Gastrointestinal Malignancies

Globally, in 2018, 4.8 million new patients have a diagnosis of gastrointestinal (GI) cancers, while 3.4 million people died of such disorders. GI malignancies are tightly relevant to 26% of the world-wide cancer incidence and occupies 35% of all cancer-associated deaths. In this article, we principally investigated molecular and cellular mechanisms of tumorigenesis in five major GI cancers occurring at esophagus, stomach, liver, pancreas, and colorectal region that illustrate high morbidity in Eastern and Western countries. Moreover, through this investigation, we not only emphasize importance of the tumor microenvironment in development and treatment of malignant tumors but also identify significance of M2PK, miRNAs, ctDNAs, circRNAs, and CTCs in early detection of GI cancers, as well as systematically evaluate contribution of personalized precision medicine including cellular immunotherapy, new antigen and vaccine therapy, and oncolytic virotherapy in treatment of GI cancers.

An independent poor-prognosis subtype of hepatocellular carcinoma based on the tumor microenvironment

Background

Hepatocellular carcinoma (HCC) is a highly malignant tumor with a particularly poor prognosis. The tumor microenvironment (TME) is closely associated with tumorigenesis, progression, and treatment. However, the relationship between TME genes and HCC patient prognosis is poorly understood.

Methods

In this study, we identified two prognostic subtypes based on the TME using data from The Cancer Genome Atlas and Gene Expression Omnibus. The Microenvironment Cell Populations-counter method was used to evaluate immune cell infiltration in HCC. Differentially expressed genes between molecular subtypes were calculated with the Limma package, and clusterProfiler was used for Gene Ontology and Kyoto Encyclopedia of Genes and Genomes functional enrichment analyses to identify genes related to the independent subtypes. We also integrated mRNA expression data into our bioinformatics analysis.

Results

We identified 4227 TME-associated genes and 640 genes related to the prognosis of HCC. We defined two major subtypes (Clusters 1 and 2) based on the analysis of TME-associated gene expression. Cluster 1 was characterized by increased expression of immune-associated genes and a worse prognosis than Cluster 2.

Conclusions

The identification of these HCC subtypes based on the TME provides further insight into the molecular mechanisms and prediction of HCC prognosis.

Decipher the Glioblastoma Microenvironment: The First Milestone for New Groundbreaking Therapeutic Strategies

Glioblastoma (GBM) is the most common primary malignant brain tumour in adults. Despite the combination of novel therapeutical approaches, it remains a deadly malignancy with an abysmal prognosis. GBM is a polymorphic tumour from both molecular and histological points of view. It consists of different malignant cells and various stromal cells, contributing to tumour initiation, progression, and treatment response. GBM’s microenvironment is multifaceted and is made up of soluble factors, extracellular matrix components, tissue-resident cell types (e.g., neurons, astrocytes, endothelial cells, pericytes, and fibroblasts) together with resident (e.g., microglia) or recruited (e.g., bone marrow-derived macrophages) immune cells. These latter constitute the so-called immune microenvironment, accounting for a substantial GBM’s tumour volume. Despite the abundance of immune cells, an intense state of tumour immunosuppression is promoted and developed; this represents the significant challenge for cancer cells’ immune-mediated destruction. Though literature data suggest that distinct GBM’s subtypes harbour differences in their microenvironment, its role in treatment response remains obscure. However, an in-depth investigation of GBM’s microenvironment may lead to novel therapeutic opportunities to improve patients’ outcomes. This review will elucidate the GBM’s microenvironment composition, highlighting the current state of the art in immunotherapy approaches. We will focus on novel strategies of active and passive immunotherapies, including vaccination, gene therapy, checkpoint blockade, and adoptive T-cell therapies.

The Association Between Inflammation and Immunosuppression: Implications for ICI Biomarker Development

Evasion of immune destruction is considered one of the hallmarks of cancer. Chronic inflammation can enable immune escape by suppressing immune surveillance and permitting the development of tumors and creating a tumor microenvironment that sustains cancer. This includes generating mechanisms that prevent the effectiveness of anti-tumor treatment including immune checkpoint inhibitor therapy. In this review, we explore the interplay of inflammation and immunosuppression, their effects on the tumor microenvironment, and their implications for immune checkpoint inhibitor therapy particularly in the context of predictive biomarkers for their use.

The roles of extracellular vesicles in the development, microenvironment, anticancer drug resistance, and therapy of head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) is one of the main malignant tumours affecting human health, mainly due to delayed diagnosis and high invasiveness. Extracellular vehicles (EVs) are membranous vesicles released by cells into the extracellular matrix that carry important signalling molecules and stably and widely exist in various body fluids, such as plasma, saliva, cerebrospinal fluid, breast milk, urine, semen, lymphatic fluid, synovial fluid, amniotic fluid, and sputum. EVs transport almost all types of bioactive molecules (DNA, mRNAs, microRNAs (miRNAs), proteins, metabolites, and even pharmacological compounds). These "cargoes" can act on recipient cells, reshaping the surrounding microenvironment and altering distant targets, ultimately affecting their biological behaviour. The extensive exploration of EVs has deepened our comprehensive understanding of HNSCC biology. In this review, we not only summarized the effect of HNSCC-derived EVs on the tumour microenvironment but also described the role of microenvironment-derived EVs in HNSCC and discussed how the "mutual dialogue" between the tumour and microenvironment mediates the growth, metastasis, angiogenesis, immune escape, and drug resistance of tumours. Finally, the clinical application of EVS in HNSCC was assessed.