Plasmacytoid Dendritic Cells as a Novel Cell-Based Cancer Immunotherapy

High expression of CCNB2 is an independent predictive poor prognostic biomarker and correlates with immune infiltrates in breast carcinoma

Background

Cyclin B2 (CCNB2) is associated with cell cycle progression, acting as a cell cycle checkpoint in progression of G2/M transition. In many cancer patients, it has been observed that overexpression of CCNB2 enhances tumor invasiveness and leads to adverse prognosis. However, the association of CCNB2 with the tumor microenvironment remains unclear. Therefore, it is necessary to clarify the associations of CCNB2 with the immune status and prognosis of breast carcinoma (BRCA).

Methods

Gene expression and clinical data for BRCA were obtained from The Cancer Genome Atlas and Gene Expression Omnibus databases, followed by association analyses of CCNB2 expression with prognosis, immune cell infiltration, and immune checkpoints. This study further performed drug sensitivity analysis and constructed a prognostic nomogram for CCNB2.

Results

3619 differentially expressed genes were identified in BRCA, including CCNB2 that emerged as a key gene in the network. High CCNB2 expression correlated with poor prognosis. Functional analysis demonstrated enrichment of CCNB2 co-expressed genes with the cell cycle, cancer progression, cell energy, and immune pathways. Microsatellite instability and tumor mutation burden analyses indicated CCNB2 as a candidate immunotherapy target. Tumor-infiltrating myeloid-derived suppressor cells, regulatory T cells, and T helper 2 cells were associated with CCNB2-related tumor progression and metastasis. CCNB2 expression positively correlated with immune checkpoints, indicating that high CCNB2 expression might facilitate tumor immune escape. Tumors with high CCNB2 expression showed sensitivity to phosphoinositide 3-kinase-protein kinase B-mammalian target of rapamycin and cyclin-dependent kinase (CDK) 4/6 inhibitors, and the nomogram had good prognostic predictive ability for patients with BRCA.

Conclusions

CCNB2 may play a crucial role in tumorigenesis and serve as an independent prognostic biomarker associated with tumor microenvironment, tumor immune infiltration and immunotherapy in BRCA.

Deciphering the Prognostic Significance of MYD88 and CD79B Mutations in Diffuse Large B-Cell Lymphoma: Insights into Treatment Outcomes

BACKGROUND

The clinical and genetic characteristics, as well as treatment outcomes, of diffuse large B-cell lymphoma (DLBCL) patients with different MYD88 and CD79B mutation status merit further investigation.

OBJECTIVE

This study aims to investigate the distinctions in clinical manifestations, genetic characteristics, and treatment outcomes among MYD88-CD79Bco-mut, MYD88/CD79Bsingle-mut, and MYD88-CD79Bco-wt DLBCL patients.

PATIENTS AND METHODS

Clinical and genetic characteristics, along with treatment outcomes among 2696 DLBCL patients bearing MYD88-CD79Bco-mut, MYD88/CD79Bsingle-mut, and MYD88-CD79Bco-wt treated with R-CHOP/R-CHOP-like regimens from the Cancer Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College and six external cohorts were analyzed. Potential molecular mechanisms were investigated through Gene Set Enrichment Analysis and xCell methodology.

RESULTS

In the MCD subtype, patients with MYD88-CD79Bco-mut showed comparable progression-free survival (PFS) and overall survival (OS) compared to MYD88/CD79Bsingle-mut or MYD88-CD79Bco-wt. However, in the non-MCD subtype, patients with MYD88-CD79Bco-mut exhibited significantly inferior OS than MYD88/CD79Bsingle-mut or MYD88-CD79Bco-wt, while there was no significant OS difference between MYD88/CD79Bsingle-mut and MYD88-CD79Bco-wt (median OS: 68.8 [95% CI 22-NA] vs NA [95% CI 112-NA] vs 177.7 [95% CI 159-NA] months; MYD88-CD79Bco-mut vs MYD88/CD79Bsingle-mut: p = 0.02; MYD88-CD79Bco-mut vs MYD88-CD79Bco-wt: p = 0.03; MYD88/CD79Bsingle-mut vs MYD88-CD79Bco-wt: p = 0.33). Regarding patients with MYD88-CD79Bco-mut, there was no significant difference in PFS and OS between the MCD and non-MCD subtypes. Within the MYD88-CD79Bco-mut group, patients with PIM1mut had better PFS than PIM1wt (median PFS: 8.34 [95% CI 5.56-NA] vs 43.8 [95% CI 26.4-NA] months; p = 0.02). Possible mechanisms contributing to the superior PFS of PIM1mut patients may include activated lymphocyte-mediated immunity and interferon response, a higher proportion of natural killer T cells and plasmacytoid dendritic cells, as well as suppressed angiogenesis and epithelial-mesenchymal transition, along with lower fibroblast and stromal score.

CONCLUSIONS

In the MCD subtype, patients with MYD88-CD79Bco-mut showed comparable PFS and OS compared to MYD88/CD79Bsingle-mut or MYD88-CD79Bco-wt, while in the non-MCD subtype, they exhibited significantly inferior OS. There was no significant disparity in PFS and OS of MYD88-CD79Bco-mut between the MCD and non-MCD subtypes. The presence of PIM1mut within the MYD88-CD79Bco-mut group correlated with better PFS, which may result from an intricate interplay of immune processes and tumor microenvironment alterations.

Dendritic cell vaccination strategy for the treatment of acute myeloid leukemia: a systematic review

BACKGROUND AIMS

Acute myeloid leukemia (AML) is classified as a hematologic malignancy characterized by the proliferation of immature blood cells within the bone marrow (BM), resulting in an aberrant and unregulated cellular growth. The primary therapeutic modalities for AML include chemotherapy and hematopoietic stem cell transplantation. However, it is important to note that these treatments are accompanied by important adverse effects and mortality rates. Therefore, the need for more effective treatment options seems necessary, and dendritic cell (DC) vaccine therapy can be one of these options. In this study, we aim to investigate the effectiveness of DC vaccination therapy for the management of AML.

METHODS

PubMed, Scopus, ProQuest, Web of Science, and Google Scholar databases were searched for this systematic review. The articles were evaluated based on the inclusion criteria of this study and initially compared in terms of titles or abstracts. Finally, the articles related to the topic of this review were obtained in full text. The complete remission and partial remission, survival, correlative immune assays, and health-related metrics were used to evaluate this cellular immunotherapy effectiveness. The quality of the studies was assessed independently using the Cochrane risk-of-bias tools. The compiled data were input into a standard Excel spreadsheet. Each domain was evaluated as having either a "low risk," "high risk," or "unclear risk" of bias.

RESULTS

Among the 3986 studies that were determined, a total of 11 correlated trials were selected for inclusion in this systematic review. DC vaccine therapy was effective in inducing complete and partial remission, and stabilization of the disease. Additionally, it was discovered that the treatment strengthened the immune system as seen by increased levels of CD4+ and CD8+ T cells, Th1 cytokines, WT1-specific T cells, and activated NK cells.

CONCLUSION

We conducted a systematic review that supports the use of DC vaccine therapy as an effective treatment for AML. The therapy demonstrated potentials in achieving remission, enhancing the immune system function, and increasing overall survival. However, more studies are required to improve the methods of preparing and delivering the DC vaccine, and to confirm its long-term safety and effectiveness.

Dendritic Cells as a Therapeutic Strategy in Acute Myeloid Leukemia: Vaccines

Dendritic cells (DCs) serve as professional antigen-presenting cells (APC) bridging innate and adaptive immunity, playing an essential role in triggering specific cellular and humoral responses against tumor and infectious antigens. Consequently, various DC-based antitumor therapeutic strategies have been developed, particularly vaccines, and have been intensively investigated specifically in the context of acute myeloid leukemia (AML). This hematological malignancy mainly affects the elderly population (those aged over 65), which usually presents a high rate of therapeutic failure and an unfavorable prognosis. In this review, we examine the current state of development and progress of vaccines in AML. The findings evidence the possible administration of DC-based vaccines as an adjuvant treatment in AML following initial therapy. Furthermore, the therapy demonstrates promising outcomes in preventing or delaying tumor relapse and exhibits synergistic effects when combined with other treatments during relapses or disease progression. On the other hand, the remarkable success observed with RNA vaccines for COVID-19, delivered in lipid nanoparticles, has revealed the efficacy and effectiveness of these types of vectors, prompting further exploration and their potential application in AML, as well as other neoplasms, loading them with tumor RNA.

Impaired activation of plasmacytoid dendritic cells via toll-like receptor 7/9 and STING is mediated by melanoma-derived immunosuppressive cytokines and metabolic drift

Introduction

Plasmacytoid dendritic cells (pDCs) infiltrate a large set of human cancers. Interferon alpha (IFN-α) produced by pDCs induces growth arrest and apoptosis in tumor cells and modulates innate and adaptive immune cells involved in anti-cancer immunity. Moreover, effector molecules exert tumor cell killing. However, the activation state and clinical relevance of pDCs infiltration in cancer is still largely controversial. In Primary Cutaneous Melanoma (PCM), pDCs density decreases over disease progression and collapses in metastatic melanoma (MM). Moreover, the residual circulating pDC compartment is defective in IFN-α production.

Methods

The activation of tumor-associated pDCs was evaluated by in silico and microscopic analysis. The expression of human myxovirus resistant protein 1 (MxA), as surrogate of IFN-α production, and proximity ligation assay (PLA) to test dsDNA-cGAS activation were performed on human melanoma biopsies. Moreover, IFN-α and CXCL10 production by in vitro stimulated (i.e. with R848, CpG-A, ADU-S100) pDCs exposed to melanoma cell lines supernatants (SN-mel) was tested by intracellular flow cytometry and ELISA. We also performed a bulk RNA-sequencing on SN-mel-exposed pDCs, resting or stimulated with R848. Glycolytic rate assay was performed on SN-mel-exposed pDCs using the Seahorse XFe24 Extracellular Flux Analyzer.

Results

Based on a set of microscopic, functional and in silico analyses, we demonstrated that the melanoma milieu directly impairs IFN-α and CXCL10 production by pDCs via TLR-7/9 and cGAS-STING signaling pathways. Melanoma-derived immunosuppressive cytokines and a metabolic drift represent relevant mechanisms enforcing pDC-mediated melanoma escape.

Discussion

These findings propose a new window of intervention for novel immunotherapy approaches to amplify the antitumor innate immune response in cutaneous melanoma (CM).

Dendritic Cell Subpopulations Are Associated with Prognostic Characteristics of Breast Cancer after Neoadjuvant Chemotherapy-An Observational Study

Breast cancer (BC) is the most prevalent malignancy in women and researchers have strived to develop optimal strategies for its diagnosis and management. Neoadjuvant chemotherapy (NAC), which reduces tumor size, risk of metastasis and patient mortality, often also allows for a de-escalation of breast and axillary surgery. Nonetheless, complete pathological response (pCR) is achieved in no more than 40% of patients who underwent NAC. Dendritic cells (DCs) are professional antigen-presenting cells present in the tumor microenvironment. The multitude of their subtypes was shown to be associated with the pathological and clinical characteristics of BC, but it was not evaluated in BC tissue after NAC. We found that highe r densities of CD123+ plasmacytoid DCs (pDCs) were present in tumors that did not show pCR and had a higher residual cancer burden (RCB) score and class. They were of higher stage and grade and more frequently HER2-negative. The density of CD123+ pCDs was an independent predictor of pCR in the studied group. DC-LAMP+ mature DCs (mDCs) were also related to characteristics of clinical relevance (i.e., pCR, RCB, and nuclear grade), although no clear trends were identified. We conclude that CD123+ pDCs are candidates for a novel biomarker of BC response to NAC.

The Potential of Dendritic Cell Subsets in the Development of Personalized Immunotherapy for Cancer Treatment

Since the discovery of dendritic cells (DCs) in 1973 by Ralph Steinman, a tremendous amount of knowledge regarding these innate immunity cells has been accumulating. Their role in regulating both innate and adaptive immune processes is gradually being uncovered. DCs are proficient antigen-presenting cells capable of activating naive T-lymphocytes to initiate and generate effective anti-tumor responses. Although DC-based immunotherapy has not yielded significant results, the substantial number of ongoing clinical trials underscores the relevance of DC vaccines, particularly as adjunctive therapy or in combination with other treatment options. This review presents an overview of current knowledge regarding human DCs, their classification, and the functions of distinct DC populations. The stepwise process of developing therapeutic DC vaccines to treat oncological diseases is discussed, along with speculation on the potential of combined therapy approaches and the role of DC vaccines in modern immunotherapy.

Dendritic Cell-Derived Exosomes in Cancer Immunotherapy

Exosomes are nanoscale vesicles released by diverse types of cells for complex intercellular communication. Numerous studies have shown that exosomes can regulate the body's immune response to tumor cells and interfere with the tumor microenvironment (TME). In clinical trials on dendritic cell (DC)-based antitumor vaccines, no satisfactory results have been achieved. However, recent studies suggested that DC-derived exosomes (DEXs) may be superior to DC-based antitumor vaccines in avoiding tumor cell-mediated immunosuppression. DEXs contain multiple DC-derived surface markers that capture tumor-associated antigens (TAAs) and promote immune cell-dependent tumor rejection. These findings indicate the necessity of the further development and improvement of DEX-based cell-free vaccines to complement chemotherapy, radiotherapy, and other immunotherapies. In this review, we highlighted the recent progress of DEXs in cancer immunotherapy, particularly by concentrating on landmark studies and the biological characterization of DEXs, and we summarized their important role in the tumor immune microenvironment (TIME) and clinical application in targeted cancer immunotherapy. This review could enhance comprehension of advances in cancer immunotherapy and contribute to the elucidation of how DEXs regulate the TIME, thereby providing a reference for utilizing DEX-based vaccines in clinical practice.

Immune Cell Infiltration Analysis Based on Bioinformatics Reveals Novel Biomarkers of Coronary Artery Disease

Background

Coronary artery disease (CAD) is a multifactorial immune disease, but research into the specific immune mechanism is still needed. The present study aimed to identify novel immune-related markers of CAD.

Methods

Three CAD-related datasets (GSE12288, GSE98583, GSE113079) were downloaded from the Gene Expression Integrated Database. Gene ontology annotation, Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis and weighted gene co-expression network analysis were performed on the common significantly differentially expressed genes (DEGs) of these three data sets, and the most relevant module genes for CAD obtained. The immune cell infiltration of module genes was evaluated with the CIBERSORT algorithm, and characteristic genes accompanied by their diagnostic effectiveness were screened by the machine-learning algorithm least absolute shrinkage and selection operator (LASSO) regression analysis. The expression levels of characteristic genes were evaluated in the peripheral blood mononuclear cells of CAD patients and healthy controls for verification.

Results

A total of 204 upregulated and 339 downregulated DEGs were identified, which were mainly enriched in the following pathways: "Apoptosis", "Th17 cell differentiation", "Th1 and Th2 cell differentiation", "Glycerolipid metabolism", and "Fat digestion and absorption". Five characteristic genes, LMAN1L, DOK4, CHFR, CEL and CCDC28A, were identified by LASSO analysis, and the results of the immune cell infiltration analysis indicated that the proportion of immune infiltrating cells (activated CD8 T cells and CD56 DIM natural killer cells) in the CAD group was lower than that in the control group. The expressions of CHFR, CEL and CCDC28A in the peripheral blood of the healthy controls and CAD patients were significantly different.

Conclusion

We identified CHFR, CEL and CCDC28A as potential biomarkers related to immune infiltration in CAD based on public data sets and clinical samples. This finding will contribute to providing a potential target for early noninvasive diagnosis and immunotherapy of CAD.

Neutrophil extracellular traps in tumor progression and immunotherapy

Tumor immunity is a growing field of research that involves immune cells within the tumor microenvironment. Neutrophil extracellular traps (NETs) are neutrophil-derived extracellular web-like chromatin structures that are composed of histones and granule proteins. Initially discovered as the predominant host defense against pathogens, NETs have attracted increasing attention due to they have also been tightly associated with tumor. Excessive NET formation has been linked to increased tumor growth, metastasis, and drug resistance. Moreover, through direct and/or indirect effects on immune cells, an abnormal increase in NETs benefits immune exclusion and inhibits T-cell mediated antitumor immune responses. In this review, we summarize the recent but rapid progress in understanding the pivotal roles of NETs in tumor and anti-tumor immunity, highlighting the most relevant challenges in the field. We believe that NETs may be a promising therapeutic target for tumor immunotherapy.

A New Plasmacytoid Dendritic Cell-Based Vaccine in Combination with Anti-PD-1 Expands the Tumor-Specific CD8+ T Cells of Lung Cancer Patients

The purpose of immune checkpoint inhibitor (ICI)-based therapies is to help the patient's immune system to combat tumors by restoring the immune response mediated by CD8+ cytotoxic T cells. Despite impressive clinical responses, most patients do not respond to ICIs. Therapeutic vaccines with autologous professional antigen-presenting cells, including dendritic cells, do not show yet significant clinical benefit. To improve these approaches, we have developed a new therapeutic vaccine based on an allogeneic plasmacytoid dendritic cell line (PDC*line), which efficiently activates the CD8+ T-cell response in the context of melanoma. The goal of the study is to demonstrate the potential of this platform to activate circulating tumor-specific CD8+ T cells in patients with lung cancer, specifically non-small-cell lung cancer (NSCLC). PDC*line cells loaded with peptides derived from tumor antigens are used to stimulate the peripheral blood mononuclear cells of NSCLC patients. Very interestingly, we demonstrate an efficient activation of specific T cells for at least two tumor antigens in 69% of patients irrespective of tumor antigen mRNA overexpression and NSCLC subtype. We also show, for the first time, that the antitumor CD8+ T-cell expansion is considerably improved by clinical-grade anti-PD-1 antibodies. Using PDC*line cells as an antigen presentation platform, we show that circulating antitumor CD8+ T cells from lung cancer patients can be activated, and we demonstrate the synergistic effect of anti-PD-1 on this expansion. These results are encouraging for the development of a PDC*line-based vaccine in NSCLC patients, especially in combination with ICIs.

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.