De novo carcinogenesis promoted by chronic inflammation is B lymphocyte dependent

Ex vivo-expanded human CD19+TIM-1+ regulatory B cells suppress immune responses in vivo and are dependent upon the TIM-1/STAT3 axis

Regulatory B cells (Breg) are a heterogenous population with immune-modulating functions. The rarity of human IL-10⁺ Breg makes translational studies difficult. Here we report ex vivo expansion of human B cells with in vivo regulatory function (expBreg). CD154-stimulation of human CD19⁺ B cells drives >900-fold expansion of IL-10⁺ B cells that is maintained in culture for 14 days. Whilst expBreg-mediated suppressive function is partially dependent on IL-10 expression, CRISPR-mediated gene deletions demonstrate predominant roles for TIM-1 and CD154. TIM-1 regulates STAT3 signalling and modulates downstream suppressive function. In a clinically relevant humanised mouse model of skin transplantation, expBreg prolongs human allograft survival. Meanwhile, CD19⁺CD73^-CD25⁺CD71⁺TIM-1⁺CD154⁺ Breg cells are enriched in the peripheral blood of human donors with cutaneous squamous cell carcinoma (SCC). TIM-1⁺ and pSTAT3⁺ B cells are also identified in B cell clusters within histological sections of human cutaneous SCC tumours. Our findings thus provide insights on Breg homoeostasis and present possible targets for Breg-related therapies.

B-Cell-Based Immunotherapy: A Promising New Alternative

The field of immunotherapy has undergone radical conceptual changes over the last decade. There are various examples of immunotherapy, including the use of monoclonal antibodies, cancer vaccines, tumor-infecting viruses, cytokines, adjuvants, and autologous T cells carrying chimeric antigen receptors (CARs) that can bind cancer-specific antigens known as adoptive immunotherapy. While a lot has been achieved in the field of T-cell immunotherapy, only a fraction of patients (20%) see lasting benefits from this mode of treatment, which is why there is a critical need to turn our attention to other immune cells. B cells have been shown to play both anti- and pro-tumorigenic roles in tumor tissue. In this review, we shed light on the dual nature of B cells in the tumor microenvironment. Furthermore, we discussed the different factors affecting the biology and function of B cells in tumors. In the third section, we described B-cell-based immunotherapies and their clinical applications and challenges. These current studies provide a springboard for carrying out future mechanistic studies to help us unleash the full potential of B cells in immunotherapy.

Members of the Chromobox Family Have Prognostic Value in Hepatocellular Carcinoma

Liver cancer is the fifth most prevalent malignant tumor, while hepatocellular carcinoma represents the most prevalent subtype worldwide. Previous studies have associated the chromobox family, critical components of epigenetic regulatory complexes, with development of many malignancies owing to their role in inhibiting differentiation and promoting proliferation of cancer cells. However, little is known regarding their function in development and progression of hepatocellular carcinoma. In the present study, we analyzed differential expression, prognostic value, immune cell infiltration, and gene pathway enrichment of chromobox family in hepatocellular carcinoma patients. Next, we performed Pearson’s correlation analysis to determine the relationships between chromobox family proteins with tumor-immune infiltration. Results revealed that high expression of CBX1, CBX2, CBX3, CBX6, and CBX8 was associated with poor survival rates of hepatocellular carcinoma patients. These five factors were used to build prognostic gene models using LASSO Cox regression analysis. Results indicated that high expression of CBX2 and CBX3 proteins was significantly associated with poor prognosis for hepatocellular carcinoma patients. The resulting nomogram revealed that CBX3 and T stages were significantly correlated with prognosis of hepatocellular carcinoma patients. Notably, predictive CBX3 was strongly correlated with immune cell infiltration. Furthermore, results from functional enrichment analysis revealed that CBX3 was mainly involved in regulation of methylation of Histone H3-K27. Collectively, these findings suggest that CBX3 could be a biomarker for predicting prognosis of hepatocellular carcinoma patients.

Enrichment of Tumor-Infiltrating B Cells in Group 4 Medulloblastoma in Children

Medulloblastoma (MB) is the most common malignant brain tumor in children. It is classified into core molecular subgroups (wingless activated (WNT), sonic hedgehog activated (SHH), Group 3 (G3), and Group 4 (G4)). In this study, we analyzed the tumor-infiltrating immune cells and cytokine profiles of 70 MB patients in Taiwan using transcriptome data. In parallel, immune cell composition in tumors from the SickKids cohort dataset was also analyzed to confirm the findings. The clinical cohort data showed the WNT and G4 MB patients had lower recurrence rates and better 5-year relapse-free survival (RFP) compared with the SHH and G3 MB patients, among the four subgroups of MB. We found tumor-infiltrating B cells (TIL-Bs) enriched in the G4 subgroups in the Taiwanese MB patients and the SickKids cohort dataset. In the G4 subgroups, the patients with a high level of TIL-Bs had better 5-year overall survival. Mast cells presented in G4 MB tumors were positively correlated with TIL-Bs. Higher levels of CXCL13, IL-36γ, and CCL27 were found compared to other subgroups or normal brains. These three cytokines, B cells and mast cells contributed to the unique immune microenvironment in G4 MB tumors. Therefore, B-cell enrichment is a G4-subgroup-specific immune signature and the presence of B cells may be an indicator of a better prognosis in G4 MB patients.

B Cell Function in the Tumor Microenvironment

The tumor microenvironment (TME) is a heterogeneous, complex organization composed of tumor, stroma, and endothelial cells that is characterized by cross talk between tumor and innate and adaptive immune cells. Over the last decade, it has become increasingly clear that the immune cells in the TME play a critical role in controlling or promoting tumor growth. The function of T lymphocytes in this process has been well characterized. On the other hand, the function of B lymphocytes is less clear, although recent data from our group and others have strongly indicated a critical role for B cells in antitumor immunity. There are, however, a multitude of populations of B cells found within the TME, ranging from naive B cells all the way to terminally differentiated plasma cells and memory B cells. Here, we characterize the role of B cells in the TME in both animal models and patients, with an emphasis on dissecting how B cell heterogeneity contributes to the immune response to cancer.

Multiple datasets to explore the tumor microenvironment of cutaneous squamous cell carcinoma

BACKGROUND

Cutaneous squamous cell carcinoma (cSCC) is one of the most frequent types of cutaneous cancer. The composition and heterogeneity of the tumor microenvironment significantly impact patient prognosis and the ability to practice precision therapy. However, no research has been conducted to examine the design of the tumor microenvironment and its interactions with cSCC.

MATERIAL AND METHODS

We retrieved the datasets GSE42677 and GSE45164 from the GEO public database, integrated them, and analyzed them using the SVA method. We then screened the core genes using the WGCNA network and LASSO regression and checked the model's stability using the ROC curve. Finally, we performed enrichment and correlation analyses on the core genes.

RESULTS

We identified four genes as core cSCC genes: DTYMK, CDCA8, PTTG1 and MAD2L1, and discovered that RORA, RORB and RORC were the primary regulators in the gene set. The GO semantic similarity analysis results indicated that CDCA8 and PTTG1 were the two most essential genes among the four core genes. The results of correlation analysis demonstrated that PTTG1 and HLA-DMA, CDCA8 and HLA-DQB2 were significantly correlated.

CONCLUSIONS

Examining the expression levels of four primary genes in cSCC aids in our understanding of the disease's pathophysiology. Additionally, the core genes were found to be highly related with immune regulatory genes, suggesting novel avenues for cSCC prevention and treatment.

B cells and tertiary lymphoid structures as determinants of tumour immune contexture and clinical outcome

B cells are a major component of the tumour microenvironment, where they are predominantly associated with tertiary lymphoid structures (TLS). In germinal centres within mature TLS, B cell clones are selectively activated and amplified, and undergo antibody class switching and somatic hypermutation. Subsequently, these B cell clones differentiate into plasma cells that can produce IgG or IgA antibodies targeting tumour-associated antigens. In tumours without mature TLS, B cells are either scarce or differentiate into regulatory cells that produce immunosuppressive cytokines. Indeed, different tumours vary considerably in their TLS and B cell content. Notably, tumours with mature TLS, a high density of B cells and plasma cells, as well as the presence of antibodies to tumour-associated antigens are typically associated with favourable clinical outcomes and responses to immunotherapy compared with those lacking these characteristics. However, polyclonal B cell activation can also result in the formation of immune complexes that trigger the production of pro-inflammatory cytokines by macrophages and neutrophils. In complement-rich tumours, IgG antibodies can also activate the complement cascade, resulting in the production of anaphylatoxins that sustain tumour-promoting inflammation and angiogenesis. Herein, we review the phenotypic heterogeneity of intratumoural B cells and the importance of TLS in their generation as well as the potential of B cells and TLS as prognostic and predictive biomarkers. We also discuss novel therapeutic approaches that are being explored with the aim of increasing mature TLS formation, B cell differentiation and anti-tumour antibody production within tumours.

"Mechanisms of induction of regulatory B cells in the tumour microenvironment and their contribution to immunosuppression and pro-tumour responses"

The presence of tumour-infiltrating immune cells was originally associated with the induction of anti-tumour responses and good a prognosis. A more refined characterization of the tumour microenvironment has challenged this original idea and evidence now exists pointing to a critical role for immune cells in the modulation of anti-tumour responses and the induction of a tolerant pro-tumour environment. The coordinated action of diverse immunosuppressive populations, both innate and adaptive, shapes a variety of pro-tumour responses leading to tumour progression and metastasis. Regulatory B cells have emerged as critical modulators and suppressors of anti-tumour responses. As reported in autoimmunity and infection studies, Bregs are a heterogeneous population with diverse phenotypes and different mechanisms of action. Here we review recent studies on Bregs from animal models and patients, covering a variety of types of cancer. We describe the heterogeneity of Bregs, the cellular interactions they make with other immune cells and the tumour itself, and their mechanism of suppression that enables tumour escape. We also discuss the potential therapeutic tools that may inhibit Bregs function and promote anti-tumour responses.

B cells in pancreatic cancer stroma

Pancreatic cancer is a disease with high unmet clinical need. Pancreatic cancer is also characterised by an intense fibrotic stroma, which harbours many immune cells. Studies in both human and animal models have demonstrated that the immune system plays a crucial role in modulating tumour onset and progression. In human pancreatic ductal adenocarcinoma, high B-cell infiltration correlates with better patient survival. Hence, B cells have received recent interest in pancreatic cancer as potential therapeutic targets. However, the data on the role of B cells in murine models is unclear as it is dependent on the pancreatic cancer model used to study. Nevertheless, it appears that B cells do organise along with other immune cells such as a network of follicular dendritic cells (DCs), surrounded by T cells and DCs to form tertiary lymphoid structures (TLS). TLS are increasingly recognised as sites for antigen presentation, T-cell activation, B-cell maturation and differentiation in plasma cells. In this review we dissect the role of B cells and provide directions for future studies to harness the role of B cells in treatment of human pancreatic cancer.

Tumor-B-cell interactions promote isotype switching to an immunosuppressive IgG4 antibody response through upregulation of IL-10 in triple negative breast cancers

BACKGROUND

Triple negative breast cancer (TNBC) is an aggressive breast cancer for which there is currently no targeted therapy. Tumor-infiltrating B-cells (TIB) have been observed in tumor tissues of TNBC patients, but their functional role is unclear. IgG4 is one of four antibody subclasses of IgG expressed and secreted by B cells. Unlike other IgG isotypes, IgG4 has an immunosuppressive function and is induced by Th2-type cytokines. In cancers such as melanoma, IgG4 has been linked with advanced disease and poor patient survival. Therefore, we sought to determine if IgG4 + B cells are present and determine the mechanisms driving isotype switching in TNBC.

METHODS

We performed co-culture assays to examine expression of Th2 cytokines by TNBC cells with and without the presence of B cells. We also performed in vitro class switching experiments with peripheral B cells with and without co-culture with TNBC cells in the presence or absence of an IL-10 blocking antibody. We examined expression of CD20+ TIB, IgG4 and Th2 cytokines by immunohistochemistry in 152 TNBC samples. Statistical analysis was done using Log-Rank and Cox-proportional hazards tests.

RESULTS

Our findings indicate that B cells interact with TNBC to drive chronic inflammatory responses through increased expression of inflammatory cytokines including the TH2 cytokines IL-4 and IL-10. In vitro class switching studies show that interactions between TNBC cell lines and B cells drive isotype switching to the IgG4 isotype in an IL-10 dependent manner. In patient tissues, expression of IgG4 correlates with CD20 and tumor expression of IL-10. Both IgG4 and tumor IL-10 are associated to shorter recurrence free survival (RFS) and overall survival (OS) in TNBC. In a multi-variant analysis, IL-10 was associated with poor outcomes indicating that tumor IL-10 may drive immune escape.

CONCLUSIONS

These findings indicate that interactions between TIB and TNBC results in activation of chronic inflammatory signals such as IL-10 and IL-4 that drive class switching to an IgG4 + subtype which may suppress antibody driven immune responses. The presence of IgG4 + B cells may serve as a biomarker for poor prognosis.

Expression of Podoplanin in Hepatocellular Carcinoma in a Sample of Egyptian Population – Immunohistopathological Study

BACKGROUND: Hepatocellular carcinoma (HCC) is a highly incident malignancy with a dreadful prognosis. It evolves through a multistep process, with a contribution from different stromal cells like cancer associated fibroblasts. Podoplanin is a glycoprotein that influences epithelial mesenchymal interplay facilitating the tumor invasion. AIM: The aim of the study was to evaluate the immunohistochemical expression of Podoplanin in HCC in cancer associated fibroblasts (CAFs) and malignant hepatocytes as well as assessing the lymphovascular density, and correlating them with the clinicopathological parameters. METHODS: Sixty formalin-fixed paraffin-embedded HCC tissue blocks were retrieved from the pathology Department of the National Hepatology and Tropical Medicine Research Institute and Kasr Al-aini Hospital during the period of January 2012 till December 2019. The specimens were obtained through partial or total hepatectomy inclusion criteria included HCC cases obtained through resection type biopsy and those having no history of pre-operative cancer therapy, while cases with insufficient data, core biopsy, and marked necrosis were excluded from the study. Tumor tissue blocks were immunostained for Podoplanin and its expression was interpreted in lymphatic vessels, CAFs, and malignant hepatocytes. RESULTS: Podoplanin expression in CAFs and malignant hepatocytes was detected in the majority of HCC cases (81.7%) and (88.3%), respectively. The malignant hepatocytes showed increased expression of Grade 1 immunostaining (36.7%). High lymphovascular density was detected over the majority of the cases (73.3%). Podoplanin expression was significantly correlated with higher mean age, male gender, presence of viral infection, cirrhosis, and higher tumor grade. Unifocal tumor mass, tumor size <5 cm, and presence of invasion showed a significant correlation with Podoplanin in malignant hepatocytes and CAFs for the formers and the later, respectively. CONCLUSION: Podoplanin is highly expressed in HCC, which could be used as a prognostic marker for lymphangiogenesis. Furthermore, within the malignant hepatocytes and CAFs suggesting a role in hepatocellular tumorigenesis. Podoplanin targeted therapy can be investigated to slow down the tumor progression and metastasis.

Cancer Immunoediting: Elimination, Equilibrium, and Immune Escape in Solid Tumors

Emphasizing the dynamic processes between cancer and host immune system, the initially discovered concept of cancer immunosurveillance has been replaced by the current concept of cancer immunoediting consisting of three phases: elimination, equilibrium, and escape. Solid tumors composed of both cancer and host stromal cells are an example how the three phases of cancer immunoediting functionally evolve and how tumor shaped by the host immune system gets finally resistant phenotype. The elimination, equilibrium, and escape have been described in this chapter in details, including the role of immune surveillance, cancer dormancy, disruption of the antigen-presenting machinery, tumor-infiltrating immune cells, resistance to apoptosis, as well as the function of tumor stroma, microvesicles, exosomes, and inflammation.

The role of B cells in the development, progression, and treatment of lymphomas and solid tumors

B cells are integral components of the mammalian immune response as they have the ability to generate antibodies against an almost infinite array of antigens. Over the past several decades, significant scientific progress has been made in understanding that this enormous B cell diversity contributes to pathogen clearance. However, our understanding of the humoral response to solid tumors and to tumor-specific antigens is unclear. In this review, we first discuss how B cells interact with other cells in the tumor microenvironment and influence the development and progression of various solid tumors. The ability of B lymphocytes to generate antibodies against a diverse repertoire of antigens and subsequently tailor the humoral immune response to specific pathogens relies on their ability to undergo genomic alterations during their development and differentiation. We will discuss key transforming events that lead to the development of B cell lymphomas. Overall, this review provides a foundation for innovative therapeutic interventions for both lymphoma and solid tumor malignancies.

The dual role of neutrophils in cancer

For the past decade, the role and importance of neutrophils in cancer is being increasingly appreciated. Research has focused on the ability of cancer-related neutrophils to either support tumor growth or interfere with it, showing diverse mechanisms through which the effects of neutrophils take place. In contrast to the historic view of neutrophils as terminally differentiated cells, mounting evidence has demonstrated that neutrophils are a plastic and diverse population of cells. These dynamic and plastic abilities allow them to perform varied and sometimes opposite functions simultaneously. In this review, we summarize and detail clinical and experimental evidence for, and underlying mechanisms of, the dual impact of neutrophils' functions, both supporting and inhibiting cancer development. We first discuss the effects of various basic functions of neutrophils, namely direct cytotoxicity, secretion of reactive oxygen species (ROS), nitric oxide (NO) and proteases, NETosis, autophagy and modulation of other immune cells, on tumor growth and metastatic progression. We then describe the clinical evidence for pro- vs anti-tumor functions of neutrophils in human cancer. We believe and show that the "net" impact of neutrophils in cancer is the sum of a complex balance between contradicting effects which occur simultaneously.

RNA sequencing of glioblastoma tissue slice cultures reveals the effects of treatment at the transcriptional level

One of the major challenges in cancer research is finding models that closely resemble tumors within patients. Human tissue slice cultures are a promising approach to provide a model of the patient's tumor biology ex vivo. Recently, it was shown that these slices can be successfully analyzed by whole transcriptome sequencing as well as automated histochemistry, increasing their usability as preclinical model. Glioblastoma multiforme (GBM) is a highly malignant brain tumor with poor prognosis and little is known about its genetic background and heterogeneity regarding therapy success. In this study, tissue from the tumors of 25 patients with primary GBM was processed into slice cultures and treated with standard therapy (irradiation and temozolomide). Total RNA sequencing and automated histochemistry were performed to enable analysis of treatment effects at a transcriptional and histological level. Slice cultures from long‐term survivors (overall survival [OS] > 24 months) exhibited more apoptosis than cultures from patients with shorter OS. Proliferation within these slices was slightly increased in contrast to other groups, but not significantly. Among all samples, 58 protein‐coding genes were upregulated and 32 downregulated in treated vs. untreated slice cultures. In general, an upregulation of DNA damage‐related and cell cycle checkpoint genes as well as enrichment of genotoxicity pathways and p53‐dependent signaling was found after treatment. Overall, the current study reproduces knowledge from former studies regarding the feasibility of transcriptomic analyses and automated histology in tissue slice cultures. We further demonstrate that the experimental data merge with the clinical follow‐up of the patients, which improves the applicability of our model system.

Integrative Analysis of Immune-Related Genes in the Tumor Microenvironment of Renal Clear Cell Carcinoma and Renal Papillary Cell Carcinoma

Kidney cancer encompasses a range of primary cancers, such as clear cell renal cell carcinoma (ccRCC) and papillary renal cell carcinoma (pRCC). Our knowledge about the tumor microenvironment (TME) of kidney cancer is still limited. Therefore, we comprehensively assessed the TME of kidney cancers (including ccRCC and pRCC) using the ESTIAMTE, and CIBERSORT algorithms, and conducted distinct functional and correlation analyses with data from The Cancer Genome Atlas (TCGA), International Cancer Genome Consortium (ICGC), Gene Expression Omnibus (GEO), Connectivity map and CellMiner database. Next, we identified two immune-related hub genes, IGLL5 and IL2RA, which play essential roles in the TME as well as on survival in ccRCC and pRCC. Furthermore, ccRCC and pRCC samples from our medical center were collected to verify the clinical application value of these two immune-related genes. A specific enrichment analysis of immune cells related to IGLL5 and IL2RA was also conducted in two types of renal cell cancer. Based on selected genes, we predicted the drug response and uncovered novel drug candidate for RCC treatment. Considering the unfavorable outcomes of kidney cancer and emerging interest in TME-targeted treatments, our results may offer insights into immune-related molecular mechanisms and possible targets to control the kidney cancer.

Targeting Immune Cells in the Tumor Microenvironment of HCC: New Opportunities and Challenges

Immune associated cells in the microenvironment have a significant impact on the development and progression of hepatocellular carcinoma (HCC) and have received more and more attention. Different types of immune-associated cells play different roles, including promoting/inhibiting HCC and several different types that are controversial. It is well known that immune escape of HCC has become a difficult problem in tumor therapy. Therefore, in recent years, a large number of studies have focused on the immune microenvironment of HCC, explored many mechanisms worth identifying tumor immunosuppression, and developed a variety of immunotherapy methods as targets, laying the foundation for the final victory in the fight against HCC. This paper reviews recent studies on the immune microenvironment of HCC that are more reliable and important, and provides a more comprehensive view of the investigation of the immune microenvironment of HCC and the development of more immunotherapeutic approaches based on the relevant summaries of different immune cells.

Indoleamine 2, 3-Dioxygenase Promotes Aryl Hydrocarbon Receptor-Dependent Differentiation Of Regulatory B Cells in Lung Cancer

Regulatory B cells (Breg) are IL-10 producing subsets of B cells that contribute to immunosuppression in the tumor microenvironment (TME). Breg are elevated in patients with lung cancer; however, the mechanisms underlying Breg development and their function in lung cancer have not been adequately elucidated. Herein, we report a novel role for Indoleamine 2, 3- dioxygenase (IDO), a metabolic enzyme that degrades tryptophan (Trp) and the Trp metabolite L-kynurenine (L-Kyn) in the regulation of Breg differentiation in the lung TME. Using a syngeneic mouse model of lung cancer, we report that Breg frequencies significantly increased during tumor progression in the lung TME and secondary lymphoid organs, while Breg were reduced in tumor-bearing IDO deficient mice (IDO^-/-). Trp metabolite L-Kyn promoted Breg differentiation in-vitro in an aryl hydrocarbon receptor (AhR), toll-like receptor-4-myeloid differentiation primary response 88, (TLR4-MyD88) dependent manner. Importantly, using mouse models with conditional deletion of IDO in myeloid-lineage cells, we identified a significant role for immunosuppressive myeloid-derived suppressor cell (MDSC)-associated IDO in modulating in-vivo and ex-vivo differentiation of Breg. Our studies thus identify Trp metabolism as a therapeutic target to modulate regulatory B cell function during lung cancer progression.

Impact of immune cells on the hallmarks of cancer: A literature review

Tumor-infiltrating immune cells (TIICs) are critical players in the tumor microenvironment, modulating cancer cell functions. TIICs are highly heterogenic and plastic and may either suppress cancers or provide support for tumor growth. A wide range of studies have shed light on how tumor-associated macrophages, dendritic cells, neutrophils, mast cells, natural killer cells and lymphocytes contribute for the establishment of several hallmarks of cancer and became the basis for successful immunotherapies. Many of those TIICs play pivotal roles in several hallmarks of cancer. This review contributes to elucidate the multifaceted roles of immune cells in cancer development, highlighting molecular components that constitute promising therapeutic targets. Additional studies are needed to clarify the relation between TIICs and hallmarks such as enabling replicative immortality, evading growth suppressors, sustaining proliferative signaling, resisting cell death and genome instability and mutation, to further explore their therapeutic potential and improve the outcomes of cancer patients.

Immunomodulation with β-glucan from Pleurotus ostreatus in patients with endocrine-dependent breast cancer

Aim: To evaluate the effect of pleuran (β-glucan from Pleurotus ostreatus) administration on the immune profile of patients with endocrine-dependent breast cancer (clinical stages I-II) in clinical and imaging remission. Methodology: Antitumor cellular immunity (CD19⁺, CD3⁺, CD4⁺ and CD8⁺ T lymphocytes, and natural killer cells) of 195 patients (49 in the pleuran group and 146 in the control group) was measured by flow cytometry. Results: We observed a significant increase in the absolute number of CD3⁺, CD19⁺, CD4⁺ and CD8⁺ T lymphocytes in the pleuran group compared with the control group. Conclusion: Our results suggest potential benefit of continuous pleuran administration on immune rehabilitation of cellular antitumor immunity and better prognosis in breast cancer patients in remission.

The Role of B Cells in Head and Neck Cancer

Simple Summary

Host immunity has established its role in deciding the course of cancer evolution. As cellular and molecular components in the tumor microenvironment peripherally appear to be at a constant interplay, favoring either tumor control or progression, it is vital to decrypt the immunity elements, which demonstrate the potential to be harnessed towards cancer elimination. Head and neck cancer has been characterized as densely immune infiltrated but at the same time a highly immunosuppressive malignancy due to a negative equilibrium between active and dysfunctional immune cell populations. B-cells constitute the cornerstone of humoral immunity; however, their role in cancer has been vastly overlooked in comparison to other immune subtypes and reports from multiple studies fail to show agreement on their prognostic impact. This review focuses on the role of B-cells on head and neck cancer with the aim to highlight their effect on anti-cancer immunity, as well as their possible impact on immunotherapy outcomes.

Abstract

Head and neck cancer comprises a heterogenous, highly immune infiltrated malignancy, defined by a predominantly immunosuppressive tumor microenvironment (TME). In recent years, PD-1/PD-L1 immune checkpoint inhibitors have become the standard of care treatment, either as monotherapy or in combination with chemotherapy agents, thus revolutionizing the therapeutic landscape of recurrent/metastatic disease. As a result, preclinical research is increasingly focusing on TME composition and pathophysiology, aiming to comprehensively characterize the specific elements and interactions affecting anti-tumor immunity, as well as to unveil novel predictive biomarkers of immunotherapy outcomes. While T lymphocytic populations have been vastly explored regarding their effect on cancer development, B-cells constitute a far less investigated, yet possibly equally important, aspect of cancer immunity. B-cell presence, either as single cells or as part of tertiary lymphoid structures within the TME, has been associated with several anti-tumor defense mechanisms, such as antigen presentation, antibody production and participation in antibody-dependent cellular cytotoxicity, and has demonstrated prognostic significance for multiple types of malignancies. However, immunoregulatory B-cell phenotypes have also been identified both peripherally and within malignant tissue, bearing inhibitory effects on numerous immune response processes. Consequently, B-cells and their subsets demonstrate the potential to become valuable cancer biomarkers and acquire a leading role in future therapeutic strategies.

Histamine in cancer immunology and immunotherapy. Current status and new perspectives

Cancer is the second leading cause of death globally and its incidence and mortality are rapidly increasing worldwide. The dynamic interaction of immune cells and tumor cells determines the clinical outcome of cancer. Immunotherapy comes to the forefront of cancer treatments, resulting in impressive and durable responses but only in a fraction of patients. Thus, understanding the characteristics and profiles of immune cells in the tumor microenvironment (TME) is a necessary step to move forward in the design of new immunomodulatory strategies that can boost the immune system to fight cancer. Histamine produces a complex and fine-tuned regulation of the phenotype and functions of the different immune cells, participating in multiple regulatory responses of the innate and adaptive immunity. Considering the important actions of histamine-producing immune cells in the TME, in this review we first address the most important immunomodulatory roles of histamine and histamine receptors in the context of cancer development and progression. In addition, this review highlights the current progress and foundational developments in the field of cancer immunotherapy in combination with histamine and pharmacological compounds targeting histamine receptors.

The Not-So-Good, the Bad and the Ugly: HPV E5, E6 and E7 Oncoproteins in the Orchestration of Carcinogenesis

Infection with HPV starts with the access of the viral particles to basal cells in the epidermis, potentially via microtraumas to the skin. The basal cells are able to keep away these pathogens in normal circumstances through a robust immune response from the host, as HPV infections are, in general, cleared within 2 to 3 weeks. However, the rare instances of persistent infection and/or in cases where the host immune system is compromised are major risk factors for the development of lesions potentially leading to malignancy. Evolutionarily, obligatory pathogens such as HPVs would not be expected to risk exposing the host to lethal cancer, as this would entail challenging their own life cycle, but infection with these viruses is highly correlated with cancer and malignancy-as in cancer of the cervix, which is almost always associated with these viruses. Despite this key associative cause and the availability of very effective vaccines against these viruses, therapeutic interventions against HPV-induced cancers are still a challenge, indicating the need for focused translational research. In this review, we will consider the key roles that the viral proteins play in driving the host cells to carcinogenesis, mainly focusing on events orchestrated by early proteins E5, E6 and E7-the not-so-good, the bad and the ugly-and discuss and summarize the major events that lead to these viruses mechanistically corrupting cellular homeostasis, giving rise to cancer and malignancy.

Personalized models of heterogeneous 3D epithelial tumor microenvironments: Ovarian cancer as a model

Intractable human diseases such as cancers, are context dependent, unique to both the individual patient and to the specific tumor microenvironment. However, conventional cancer treatments are often nonspecific, targeting global similarities rather than unique drivers. This limits treatment efficacy across heterogeneous patient populations and even at different tumor locations within the same patient. Ultimately, this poor efficacy can lead to adverse clinical outcomes and the development of treatment-resistant relapse. To prevent this and improve outcomes, it is necessary to be selective when choosing a patient's optimal adjuvant treatment. In this review, we posit the use of personalized, tumor-specific models (TSM) as tools to achieve this remarkable feat. First, using ovarian cancer as a model disease, we outline the heterogeneity and complexity of both the cellular and extracellular components in the tumor microenvironment. Then we examine the advantages and disadvantages of contemporary cancer models and the rationale for personalized TSM. We discuss how to generate precision 3D models through careful and detailed analysis of patient biopsies. Finally, we provide clinically relevant applications of these versatile personalized cancer models to highlight their potential impact. These models are ideal for a myriad of fundamental cancer biology and translational studies. Importantly, these approaches can be extended to other carcinomas, facilitating the discovery of new therapeutics that more effectively target the unique aspects of each individual patient's TME. STATEMENT OF SIGNIFICANCE: In this article, we have presented the case for the application of biomaterials in developing personalized models of complex diseases such as cancers. TSM could bring about breakthroughs in the promise of precision medicine. The critical components of the diverse tumor microenvironments, that lead to treatment failures, include cellular- and extracellular matrix- heterogeneity, and biophysical signals to the cells. Therefore, we have described these dynamic components of the tumor microenvironments, and have highlighted how contemporary biomaterials can be utilized to create personalized in vitro models of cancers. We have also described the application of the TSM to predict the dynamic patterns of disease progression, and predict effective therapies that can produce durable responses, limit relapses, and treat any minimal residual disease.

B cells and cancer: To B or not to B?

Whereas T cells have been considered the major immune cells of the tumor microenvironment able to induce tumor regression and control cancer clinical outcome, a burst of recent publications pointed to the fact that B cells may also play a prominent role. Activated in germinal centers of tertiary lymphoid structures, B cells can directly present tumor-associated antigens to T cells or produce antibodies that increase antigen presentation to T cells or kill tumor cells, resulting in a beneficial clinical impact. Immune complexes can also increase inflammation, angiogenesis, and immunosuppression via macrophage and complement activation, resulting in deleterious impact.

Anti-Obesity Drug Orlistat Alleviates Western-Diet-Driven Colitis-Associated Colon Cancer via Inhibition of STAT3 and NF-κB-Mediated Signaling

Many researchers have argued that Western diet (WD)-induced obesity accelerates inflammation and that inflammation is a link between obesity and colorectal cancer (CRC). This study investigated the effect of WDs on the development and progression of colitis-associated colon cancer (CAC) and the efficacy of the anti-obesity agent orlistat on WD-driven CAC in mice. The results revealed that the WD exacerbated CAC in azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced mice, which showed increased mortality, tumor formation, and aggravation of tumor progression. Furthermore, WD feeding also upregulated inflammation, hyperplasia, and tumorigenicity levels through the activation of STAT3 and NF-κB signaling in an AOM/DSS-induced mouse model. In contrast, treatment with orlistat increased the survival rate and alleviated the symptoms of CAC, including a recovery in colon length and tumor production decreases in WD-driven AOM/DSS-induced mice. Additionally, orlistat inhibited the extent of inflammation, hyperplasia, and tumor progression via the inhibition of STAT3 and NF-κB activation. Treatment with orlistat also suppressed the β-catenin, slug, XIAP, Cdk4, cyclin D, and Bcl-2 protein levels in WD-driven AOM/DSS-induced mice. The results of this study indicate that orlistat alleviates colon cancer promotion in WD-driven CAC mice by suppressing inflammation, especially by inhibiting STAT3 and NF-κB activation.

Targeted Immunotherapies in Gastrointestinal Cancer: From Molecular Mechanisms to Implications

Gastrointestinal cancer is a leading cause of cancer-related mortality and remains a major challenge for cancer treatment. Despite the combined administration of modern surgical techniques and chemoradiotherapy (CRT), the overall 5-year survival rate of gastrointestinal cancer patients in advanced stage disease is less than 15%, due to rapid disease progression, metastasis, and CRT resistance. A better understanding of the mechanisms underlying cancer progression and optimized treatment strategies for gastrointestinal cancer are urgently needed. With increasing evidence highlighting the protective role of immune responses in cancer initiation and progression, immunotherapy has become a hot research topic in the integrative management of gastrointestinal cancer. Here, an overview of the molecular understanding of colorectal cancer, esophageal cancer and gastric cancer is provided. Subsequently, recently developed immunotherapy strategies, including immune checkpoint inhibitors, chimeric antigen receptor T cell therapies, tumor vaccines and therapies targeting other immune cells, have been described. Finally, the underlying mechanisms, fundamental research and clinical trials of each agent are discussed. Overall, this review summarizes recent advances and future directions for immunotherapy for patients with gastrointestinal malignancies.

Exploration of Immune-Related Gene Expression in Osteosarcoma and Association With Outcomes

IMPORTANCE

Host immune dysregulation is associated with initiation and development of osteosarcoma. In addition, immunotherapy for osteosarcomas requires some knowledge of the immune state of patients.

OBJECTIVE

To perform an immunogenomic landscape analysis based on The Cancer Genome Atlas (TCGA) project, which provides osteosarcoma samples with clinical information.

DESIGN, SETTING, AND PARTICIPANTS

This genetic association study was conducted from July 20, 2020, to September 20, 2020, as a secondary analysis of public data. Cox regression and risk score analyses were used to construct signatures of immune-related genes (IRGs) in 84 patients with osteosarcoma from TCGA with corresponding clinical information. Patients were divided into high- and low-risk groups with 42 individuals in each group according to their risk scores. Data were analyzed from July 20 to September 20, 2020.

MAIN OUTCOMES AND MEASURES

Differentially expressed genes (DEGs) were analyzed between groups, and potential molecular mechanisms, expression regulation, and immune cell infiltration were also explored using bioinformation methods. A prognostic model based on independent risk factors selected from multivariate Cox hazard ratio regression was established to estimate 1-year overall survival.

RESULTS

In this genetic association study based on 84 samples from patients with osteosarcoma from TCGA (mean [SD] age, 15.0 [4.8] years; 47 [56.0%] men; mean [SD] follow-up time, 4.1 [2.8] years), a total of 14 survival-associated IRGs were identified. Patients assigned to the high-risk group had worse survival than patients from the low-risk group (1 death [2.4%] vs 26 deaths [61.9%%]; P < .001). The protein digestion and absorption pathway was one of the associated pathways in the functional enrichment analysis (gene ratio, 2:8; P < .001). The prognostic model based on metastases at diagnosis and risk score performed well in 1-year overall survival estimations (area under the curve, 0.947; 95% CI, 0.832-0.972). The risk score was correlated with immune cell infiltration (B cells: r = 0.331; P = .002; macrophages: r = 0.410; P < .001; CD8 T cells: r = 0.230; P = .04).

CONCLUSIONS AND RELEVANCE

This genetic association study developed a prognostic modeling tool for osteosarcoma based on IRG expression profiles, which could result in improved survival rates through more individualized therapies. Further research on IRG expression profiles could provide potential targets for future studies on immune treatment for osteosarcoma.

Immune Microenvironment Features and Dynamics in Hodgkin Lymphoma

Simple Summary

As happens in all neoplasms, the many reciprocal interactions taking place between neoplastic cells and the other reactive cells impact the course of the disease. Hodgkin Lymphoma is an haematologic malignancy where most of the pathological tissue is indeed composed by reactive cells and few neoplastic cells. Consequently, it represents an interesting subject for the description of the neoplastic and non-neoplastic cells interaction. In this review we report and discuss the more recent findings of microenvironmental studies about this disease.

Abstract

Classical Hodgkin’s lymphoma (cHL) accounts for 10% of all lymphoma diagnosis. The peculiar feature of the disease is the presence of large multinucleated Reed–Sternberg and mononuclear Hodgkin cells interspersed with a reactive microenvironment (ME). Due to the production of a large number of cytokines, Hodgkin cells (HCs) and Hodgkin Reed–Sternberg cells (HRSCs) attract and favour the expansion of different immune cell populations, modifying their functional status in order to receive prosurvival stimuli and to turn off the antitumour immune response. To this purpose HRSCs shape a biological niche by organizing the spatial distribution of cells in the ME. This review will highlight the contribution of the ME in the pathogenesis and prognosis of cHL and its role as a possible therapeutic target.

A Signaling View into the Inflammatory Tumor Microenvironment

The development of tumors requires an initiator event, usually exposure to DNA damaging agents that cause genetic alterations such as gene mutations or chromosomal abnormalities, leading to deregulated cell proliferation. Although the mere stochastic accumulation of further mutations may cause tumor progression, it is now clear that an inflammatory microenvironment has a major tumor-promoting influence on initiated cells, in particular when a chronic inflammatory reaction already existed before the initiated tumor cell was formed. Moreover, inflammatory cells become mobilized in response to signals emanating from tumor cells. In both cases, the microenvironment provides signals that initiated tumor cells perceive by membrane receptors and transduce via downstream kinase cascades to modulate multiple cellular processes and respond with changes in cell gene expression, metabolism, and morphology. Cytokines, chemokines, and growth factors are examples of major signals secreted by immune cells, fibroblast, and endothelial cells and mediate an intricate cell-cell crosstalk in an inflammatory microenvironment, which contributes to increased cancer cell survival, phenotypic plasticity and adaptation to surrounding tissue conditions. Eventually, consequent changes in extracellular matrix stiffness and architecture, coupled with additional genetic alterations, further fortify the malignant progression of tumor cells, priming them for invasion and metastasis. Here, we provide an overview of the current knowledge on the composition of the inflammatory tumor microenvironment, with an emphasis on the major signals and signal-transducing events mediating different aspects of stromal cell-tumor cell communication that ultimately lead to malignant progression.

B cells in lung cancer-not just a bystander cell: a literature review

Metastatic lung cancer represents a significant global issue where it is responsible for the most cancer diagnoses and deaths worldwide. Treatment for advanced lung cancer has undergone a series of paradigm shifts from chemotherapy to targeted molecular agents to the most recent immunotherapy strategies. The most successful of the latter involves antibodies that block inhibitory receptors on tumor infiltrating T cells, thereby enhancing T cell activity against tumor cells. However, only a subset of patients demonstrate durable responses to these drugs and treatment resistance is common. Emerging evidence suggests that a critical role exists for B cells as more than a bystander immune cell in the tumor microenvironment (TME). However, this role is likely context-specific where B cells comprise distinct subtypes with unique effector functions that may result in anti- or pro-tumor effects. As such, the balance between various B cell subtypes affects the net B cell impact upon tumor immunity. To date, the factors needed to polarize B cell function toward anti-tumor activity are unclear. Understanding B cell biology in the lung cancer setting will help redefine and refine treatment strategies to augment anti-tumor immunity. This article presents a review of the literature describing the current knowledge of the development and function of B cells, and explores their role in lung cancer and potential as an immunotherapeutic strategy and as a predictive marker for response to immune checkpoint blockade.

Spatiotemporal Analysis of B Cell- and Antibody Secreting Cell-Subsets in Human Melanoma Reveals Metastasis-, Tumor Stage-, and Age-Associated Dynamics

Background: The role of tumor-associated B cells in human cancer is only starting to emerge. B cells typically undergo a series of developmental changes in phenotype and function, however, data on the composition of the B cell population in human melanoma are largely absent including changes during tumor progression and their potential clinical significance.

Methods: In this study, we compared the number and distribution of six major B cell and antibody secreting cell subpopulations outside tertiary lymphoid structures in whole tumor sections of 154 human cutaneous melanoma samples (53 primary tumors without subsequent metastasis, 44 primary tumors with metastasis, 57 metastatic samples) obtained by seven color multiplex immunohistochemistry and automated tissue imaging and analysis.

Results: In primary melanomas, we observed the highest numbers for plasmablast-like, memory-like, and activated B cell subtypes. These cells showed a patchy, predominant paratumoral distribution at the invasive tumor-stroma margin. Plasma cell-like cells were hardly detected, germinal center- and transitional/regulatory-like B cells not at all. Of the major clinicopathologic prognostic factors for primary melanomas, metastasis was associated with decreased memory-like B cell numbers and a higher age associated with higher plasmablast-like cell numbers. When we compared the composition of B cell subpopulations in primary melanomas and metastatic samples, we found a significantly higher proportion of plasma cell-like cells at distant metastatic sites and a higher proportion of memory-like B cells at locoregional than distant metastatic sites. Both cell types were detected mainly in the para- and intratumoral stroma.

Conclusion: These data provide a first comprehensive and comparative spatiotemporal analysis of major B cell and antibody secreting cell subpopulations in human melanoma and describe metastasis-, tumor stage-, and age-associated dynamics, an important premise for B cell-related biomarker and therapy studies.

Tumor-Associated Neutrophils Drive B-cell Recruitment and Their Differentiation to Plasma Cells

A major mechanism through which neutrophils have been suggested to modulate tumor progression involves the interaction and subsequent modulation of other infiltrating immune cells. B cells have been found to infiltrate various cancer types and play a role in tumor immunity, offering new immunotherapy opportunities. Nevertheless, the specific impact of tumor-associated neutrophils (TAN) on B cells has largely been overlooked. In the current study, we aimed to characterize the role of TANs in the recruitment and modulation of B cells in the tumor microenvironment (TME). We showed that TANs actively participate in the recruitment of B cells to the TME and identified TNFα as the major cytokine mediating B-cell chemotaxis by TANs. The recruitment of CD45⁺B220⁺CD138^- splenic B cells by TANs in vitro resulted in B-cell phenotypic modulation, with 68.6% ± 2.1% of the total migrated B cells displaying a CD45^-B220⁺CD138⁺ phenotype, which is typical for plasma cells. This phenotype mirrored the large proportion (54.0% ± 6.1%) of CD45^-B220⁺CD138⁺ intratumoral B cells (i.e., plasma cells) in Lewis lung carcinoma tumors. We next confirmed that the differentiation of CD45⁺B220⁺CD138^- B cells to functionally active CD45^-B220⁺CD138⁺ plasma cells required contact with TANs, was independent of T cells, and resulted in IgG production. We further identified membranal B-cell activating factor (BAFF) on TANs as a potential contact mechanism mediating B-cell differentiation, as blocking BAFF-receptor (BAFF-R) significantly reduced IgG production by 20%. Our study, therefore, demonstrates that TANs drive the recruitment and modulation of B cells into plasma cells in the TME, hence opening new avenues in the targeting of the immune system in cancer.

Immune Cells and Immunoglobulin Expression in the Mammary Gland Tumors of Dog

Inflammatory cells have a role in tumor progression and have prognostic and therapeutic potential. The immunohistochemical expression for Mast Cell Tryptase, Macrophage Marker, CD79a, IgA, IgM and IgG on 43 cases of canine mammary gland lesions was analyzed. In hyperplasia, a few B cells (BCs) and Tumor-Associated Macrophages (TAMs) were observed, while the number of Tumor-Associated Mast Cells (TAMCs) was the highest. In the peritumoral stroma of malignant lesions, low number of TAMCs and a high number of TAMAs and BCs were present. Immune cells of each type were always lower in the intratumoral than peritumoral stroma. Positivity to CD79a was also detected in the epithelial cells of simple and micropapillay carcinomas. Immunoglobulin reactivity was mainly located in the epithelial cells where an intense positivity to IgA and IgG and a weak positivity for IgM were detectable. On the basis of our preliminary results and literature data, we suggest that such cells and molecules could be directly involved in the biology of canine mammary gland tumors. In breast cancer, stromal inflammatory cells and cancer derived immunoglobulins have been correlated with the progression, malignancy and poor prognosis of the tumor. The results herein reported show that the dog's mammary gland epithelium also expresses immunoglobulins, and they mostly show a direct relationship with the infiltration of macrophages. In addition, this study shows that the infiltration of mast cells, B-cells and macrophages varies depending on the degree of malignancy of neoplasia.

Immune Checkpoints in Pediatric Solid Tumors: Targetable Pathways for Advanced Therapeutic Purposes

The tumor microenvironment (TME) represents a complex network between tumor cells and a variety of components including immune, stromal and vascular endothelial cells as well as the extracellular matrix. A wide panel of signals and interactions here take place, resulting in a bi-directional modulation of cellular functions. Many stimuli, on one hand, induce tumor growth and the spread of metastatic cells and, on the other hand, contribute to the establishment of an immunosuppressive environment. The latter feature is achieved by soothing immune effector cells, mainly cytotoxic T lymphocytes and B and NK cells, and/or through expansion of regulatory cell populations, including regulatory T and B cells, tumor-associated macrophages and myeloid-derived suppressor cells. In this context, immune checkpoints (IC) are key players in the control of T cell activation and anti-cancer activities, leading to the inhibition of tumor cell lysis and of pro-inflammatory cytokine production. Thus, these pathways represent promising targets for the development of effective and innovative therapies both in adults and children. Here, we address the role of different cell populations homing the TME and of well-known and recently characterized IC in the context of pediatric solid tumors. We also discuss preclinical and clinical data available using IC inhibitors alone, in combination with each other or administered with standard therapies.

Risk Factors for Gastric Cancer after the Eradication of Helicobacter pylori Evaluated Based on the Background Gastric Mucosa: A Propensity Score-matched Case-control Study

Objective The eradication of Helicobacter pylori (H. pylori) reduces the risk for gastric cancer (GC) development, but it cannot prevent GC completely. We investigated the risk factors of early GC development after the eradication of H. pylori, based on the histological characteristics of gastric mucosa. Methods Sixty-one patients who underwent endoscopic submucosal dissection for early GC after successful H. pylori eradication (Group A) and 122 patients without developing a gastric neoplasm over 3 years after successful H. pylori eradication (Group B) were analyzed. We compared the histological findings of the patients enrolled in Group A and Group B before and after the propensity score-matching. Results Comparing the characteristics of two the groups, Group A consisted predominantly of males, had significantly more elderly patients, and the years after successful eradication tended to be longer. We performed score matching for these three factors to reduce the influence of any confounding factors. After matching, the scores of inflammation for Group A (n=54) was significantly higher than those of Group B (n=54) at the greater curvature of the antrum, the lesser curvature of the corpus, and the greater curvature of the corpus. According to a multivariate analysis, inflammation of the greater curvature of the antrum and lesser curvature of the corpus were found to be independent risk factors. The risk ratio and 95% CI were 5.92 (2.11-16.6) (p<0.01), and 3.56 (1.05-13.2) (p=0.04), respectively. Conclusion A continuous high level of inflammation of the background gastric mucosa may be a risk factor for gastric cancer onset after H. pylori eradication.

CD169+ lymph node macrophages have protective functions in mouse breast cancer metastasis

Although the contribution of macrophages to metastasis is widely studied in primary tumors, the involvement of macrophages in tumor-draining lymph nodes (LNs) in this process is less clear. We find CD169⁺ macrophages as the predominant macrophage subtype in naive LNs, which undergo proliferative expansion in response to tumor stimuli. CD169⁺ LN macrophage depletion, using an anti-CSF-1R antibody or clodronate-loaded liposomes, leads to increased metastatic burden in two mouse breast cancer models. The expansion of CD169⁺ macrophages is tightly connected to B cell expansion in tumor-draining LNs, and B cell depletion abrogates the effect of CD169⁺ macrophage absence on metastasis, indicating that the CD169⁺ macrophage anti-metastatic effects require B cell presence. These results reveal a protective role of CD169⁺ LN macrophages in breast cancer metastasis and raise caution for the use of drugs aiming at the depletion of tumor-associated macrophages, which might simultaneously deplete macrophages in tumor-draining LNs.

The construction and analysis of tumor-infiltrating immune cells and ceRNA networks in metastatic adrenal cortical carcinoma

Purpose: To construct and analyze tumor-infiltrating immune cell and ceRNA (competitive endogenous RNA) networks in metastatic adrenal cortical carcinoma (ACC).

Methods: A ceRNA network was established to identify the ceRNAs involved in metastasis of ACC based on 92 samples from TCGA, including 18 cases of metastasis and 74 cases of non-metastatic primary tumors. And the algorithm “cell type identification by estimating relative subsets of RNA transcripts (CIBERSORT)” was used to quantify the proportion of immune cells in ACC. In addition, predictive nomograms based on the types of important immune cells or ceRNAs were constructed to predict ACC prognosis. Moreover, we evaluated the relationships between metastatic ACC-specific immune cells and ceRNA networks to identify the potential immune gene characteristics.

Results: Ten prognostic biomarkers were identified as key members of the ceRNA network and three tumor-infiltrating immune cells were identified by CIBERSORT algorithm. Some important co-expression patterns between immune cells and ceRNAs network indicate significant correlation between Macrophages M0 and hsa-miR-130b-3p (P < 0.001), Macrophages M0 and H2AFX (P = 0.003).

Conclusions: The present study inferred that the metastasis-related ceRNAs of H2AFX, hsa-miR-130b-3p and Macrophages M0 might play important roles in ACC metastasis.

Equine Genital Squamous Cell Carcinoma Associated with EcPV2 Infection: RANKL Pathway Correlated to Inflammation and Wnt Signaling Activation

Simple Summary

Equine genital squamous cell carcinomas (egSCCs) associated with papilloma virus (PV) infection have been recently proposed as model for human PV-induced SCC. In both species, PV mucosal infections often induce cervical, oropharyngeal, penile, anal, vaginal, and vulvar cancer. The aim of this study was to clarify the molecular mechanisms behind egSCCs associated with equine papillomavirus 2 (EcPV2) infection investigating receptor activator of nuclear factor-kappa B ligand (RANKL), Wnt, and interleukin (IL)17 signaling pathways. RANKL has been recently demonstrated to play a crucial role in several human tumors, associated with a poor prognosis and metastatic spread; novel targeted therapies through RANKL silencing monoclonal antibodies have been undertaken. EcPV2-E6 DNA was checked, and viral presence was confirmed in 91% of cases, whereas oncogene expression was 60.8% for E6 and 34.7% for E2. RANKL, NFKBp50, NFKBp65, IL6, IL17, IL23p19, IL8, IL12p35, IL12p40, BCATN1, FOSL1, and LEF1 gene expression showed a significant upregulation in tumor samples compared to healthy tissues. Our results describe an inflammatory environment characterized by the increased expression of several cytokines and the activation of RANKL/RANK, IL17A, and canonical and non-canonical Wnt signaling pathways. These results may be helpful to identify new targets for immunotherapy strategies confirming egSCCs as a model for the human disease.

Abstract

Equine genital squamous cell carcinomas (egSCCs) are among the most common equine tumors after sarcoids, severely impairing animal health and welfare. Equus caballus papillomavirus type 2 (EcPV2) infection is often related to these tumors. The aim of this study was to clarify the molecular mechanisms behind egSCCs associated with EcPV2 infection, investigating receptor activator of nuclear factor-kappa B ligand (RANKL) signaling in NF-kB pathway, together with the Wnt and IL17 signaling pathways. We analyzed the innate immune response through gene expression evaluation of key cytokines and transcription factors. Moreover, Ki67 index was assessed with immunohistochemistry. EcPV2-E6 DNA was checked, and viral presence was confirmed in 21 positive out to 23 cases (91%). Oncogene expression was confirmed in 14 cases (60.8%) for E6 and in 8 (34.7%) for E2. RANKL, nuclear factor kappa-light-chain-enhancer of activated B cells (NFKB)-p50, NFKBp65, interleukin (IL)-6, IL17, IL23p19, IL8, IL12p35, IL12p40, β-catenin (BCATN1), FOS like 1 (FOSL1), and lymphoid enhancer binding factor 1 (LEF1) showed a significant upregulation in tumor samples compared to healthy tissues. Our results describe an inflammatory environment characterized by the activation of RANKL/RANK and IL17 with the relative downstream pathways, and a positive modulation of inflammatory cytokines genes such as IL6 and IL8. Moreover, the increase of BCATN1, FOSL1, and LEF1 gene expression suggests an activation of both canonical and non-canonical Wnt signaling pathway that could be critical for carcinogenesis and tumor progression.

Complex Interaction Among Immune, Inflammatory, and Carcinogenic Mechanisms in the Head and Neck Squamous Cell Carcinoma

Inflammation is deeply involved in the development of most types of cancer. Many studies focus on the interaction between immune-inflammatory mechanisms and tumorigenesis in the head and neck squamous cell carcinoma (HNSCC). In this chapter, we emphasize the complexity of processes underlying this interaction and discuss the mechanisms of carcinogenesis in HNSCC with a special focus on metabolic changes, inflammation, and the immune landscape. Unveiling complex connections between immuno-inflammatory processes and tumor initiation, promotion, and progression will open new directions in the reliable identification of predictive factors and therapeutic targets in HNSCC.

B-cell clusters at the invasive margin associate with longer survival in early-stage oral-tongue cancer patients

In oral-cancer, the number of tumor-infiltrating lymphocytes (TILs) associates with improved survival, yet the prognostic value of the cellular composition and localization of TILs is not defined. We quantified densities, localizations, and cellular networks of lymphocyte populations in 138 patients with T1-T2 primary oral-tongue squamous cell carcinoma treated with surgical resections without any perioperative (chemo)radiotherapy, and correlated outcomes to overall survival (OS). Multiplexed in-situ immunofluorescence was performed for DAPI, CD4, CD8, CD20, and pan-cytokeratin using formalin-fixed paraffin-embedded sections, and spatial distributions of lymphocyte populations were assessed in the tumor and stroma compartments at the invasive margin (IM) as well as the center of tumors. We observed a high density of CD4, CD8, and CD20 cells in the stroma compartment at the IM, but neither lymphocyte densities nor networks as single parameters associated with OS. In contrast, assessment of two contextual parameters within the stroma IM region of tumors, i.e., the number of CD20 cells within 20 µm radii of CD20 and CD4 cells, termed the CD20 Cluster Score, yielded a highly significant association with OS (HR 0.38; p = .003). Notably, the CD20 Cluster Score significantly correlated with better OS and disease-free survival in multivariate analysis (HR 0.34 and 0.47; p = .001 and 0.019) as well as with lower local recurrence rate (OR: 0.13; p = .028). Taken together, our study showed that the presence of stromal B-cell clusters at IM, in the co-presence of CD4 T-cells, associates with good prognosis in early oral-tongue cancer patients.

NF-κB in Cancer Immunity: Friend or Foe?

The emergence of immunotherapies has definitely proven the tight relationship between malignant and immune cells, its impact on cancer outcome and its therapeutic potential. In this context, it is undoubtedly critical to decipher the transcriptional regulation of these complex interactions. Following early observations demonstrating the roles of NF-κB in cancer initiation and progression, a series of studies converge to establish NF-κB as a master regulator of immune responses to cancer. Importantly, NF-κB is a family of transcriptional activators and repressors that can act at different stages of cancer immunity. In this review, we provide an overview of the selective cell-intrinsic contributions of NF-κB to the distinct cell types that compose the tumor immune environment. We also propose a new view of NF-κB targeting drugs as a new class of immunotherapies for cancer.

Inflammatory B cells correlate with failure to checkpoint blockade in melanoma patients

The understanding of the role of B cells in patients with solid tumors remains insufficient. We found that circulating B cells produced TNFα and/or IL-6, associated with unresponsiveness and poor overall survival of melanoma patients treated with anti-CTLA4 antibody. Transcriptome analysis of B cells from melanoma metastases showed enriched expression of inflammatory response genes. Publicly available single B cell data from the tumor microenvironment revealed a negative correlation between TNFα expression and response to immune checkpoint blockade. These findings suggest that B cells contribute to tumor growth via the production of inflammatory cytokines. Possibly, these B cells are different from tertiary lymphoid structure-associated B cells, which have been described to correlate with favorable clinical outcome of cancer patients. Further studies are required to identify and characterize B cell subsets and their functions promoting or counteracting tumor growth, with the aim to identify biomarkers and novel treatment targets.

Interleukin-1β-induced pancreatitis promotes pancreatic ductal adenocarcinoma via B lymphocyte-mediated immune suppression

OBJECTIVE

Long-standing chronic pancreatitis is an established risk factor for pancreatic ductal adenocarcinoma (PDAC). Interleukin-1β (IL-1β) has been associated in PDAC with shorter survival. We employed murine models to investigate the mechanisms by which IL-1β and chronic pancreatitis might contribute to PDAC progression.

DESIGN

We crossed LSL-Kras^+/G12D;Pdx1-Cre (KC) mice with transgenic mice overexpressing IL-1β to generate KC-IL1β mice, and followed them longitudinally. We used pancreatic 3D in vitro culture to assess acinar-to-ductal metaplasia formation. Immune cells were analysed by flow cytometry and immunohistochemical staining. B lymphocytes were adoptively transferred or depleted in Kras-mutant mice. B-cell infiltration was analysed in human PDAC samples.

RESULTS

KC-IL1β mice developed PDAC with liver metastases. IL-1β treatment increased Kras^+/G12D pancreatic spheroid formation. CXCL13 expression and B lymphocyte infiltration were increased in KC-IL1β pancreata. Adoptive transfer of B lymphocytes from KC-IL1β mice promoted tumour formation, while depletion of B cells prevented tumour progression in KC-IL1β mice. B cells isolated from KC-IL1β mice had much higher expression of PD-L1, more regulatory B cells, impaired CD8⁺ T cell activity and promoted tumorigenesis. IL-35 was increased in the KC-IL1β pancreata, and depletion of IL-35 decreased the number of PD-L1⁺ B cells. Finally, in human PDAC samples, patients with PDAC with higher B-cell infiltration within tumours showed significantly shorter survival.

CONCLUSION

We show here that IL-1β promotes tumorigenesis in part by inducing an expansion of immune-suppressive B cells. These findings point to the growing significance of B suppressor cells in pancreatic tumorigenesis.

The neglected brothers come of age: B cells and cancer

The opposing roles of innate and adaptive immune cells in suppressing or supporting cancer initiation, progression, metastasis and response to therapy has been long debated. The mechanisms by which different monocyte and T cell subtypes affect and modulate cancer have been extensively studied. However, the role of B cells and their subtypes have remained elusive, perhaps partially due to their heterogeneity and range of actions. B cells can produce a variety of cytokines and present tumor-derived antigens to T cells in combination with co-stimulatory or inhibitory ligands based on their phenotype. Unlike most T cells, B cells can be activated by innate immune stimuli, such as endotoxin. Furthermore, the isotype and specificity of the antibodies produced by plasma cells regulate distinct immune responses, including opsonization, antibody-mediated cellular cytotoxicity (ADCC) and complement activation. B cells are shaped by the tumor environment (TME), with the capability to regulate the TME in return. In this review, we will describe the mechanisms of B cell action, including cytokine production, antigen presentation, ADCC, opsonization, complement activation and how they affect tumor development and response to immunotherapy. We will also discuss how B cell fate within the TME is affected by tumor stroma, microbiome and metabolism.

The tumor-promoting effects of the adaptive immune system: a cause of hyperprogressive disease in cancer?

Adaptive antitumor immune responses, either cellular or humoral, aim at eliminating tumor cells expressing the cognate antigens. There are some instances, however, where these same immune responses have tumor-promoting effects. These effects can lead to the expansion of antigen-negative tumor cells, tumor cell proliferation and tumor growth, metastatic dissemination, resistance to antitumor therapy and apoptotic stimuli, acquisition of tumor-initiating potential and activation of various forms of survival mechanisms. We describe the basic mechanisms that underlie tumor-promoting adaptive immune responses and try to identify the variables that induce the switching of a tumor-inhibitory, cellular or humoral immune response, into a tumor-promoting one. We suggest that tumor-promoting adaptive immune responses may be at the origin of at least a fraction of hyperprogressive diseases (HPD) that are observed in cancer patients during therapy with immune checkpoint inhibitors (ICI) and, less frequently, with single-agent chemotherapy. We also propose the use of non-invasive biomarkers allowing to predict which patients may undergo HPD during ICI and other forms of antitumor therapy. Eventually, we suggest possibilities of therapeutic intervention allowing to inhibit tumor-promoting adaptive immune responses.

Regulatory B cells in cancer

Tumorigenesis proceeds through discrete steps where acquisition of genetic lesions and changes in the surrounding microenvironment combine to drive unrestricted neoplastic proliferation and metastasis. The ability of tumor-infiltrating immune cells to promote tumor growth via the provision of signals that enable tumor cell survival and proliferation as well as contribute to immune suppression is an active area of research. Recent efforts have provided us with mechanistic insights into how B cells can positively and negatively regulate immune responses. Negative regulation of immune responses in cancer can be mediated by regulatory B cells and is often a result of increased production of cytokines that can directly and indirectly affect anti-tumor immune function and cancer cell growth. Signals that lead to the expansion of regulatory B cells and the spectrum of their functional roles are not well understood and are the subject of active research by many groups. Here, we elaborate broadly on the history of regulatory B cells in cancer and summarize recent studies that have established genetic models for the study of regulatory B cell function and their potential for therapeutic intervention in the setting of solid cancers.