IL-9 and IL-9-producing cells in tumor immunity

Tumour Microenvironment: The General Principles of Pathogenesis and Implications in Diffuse Large B Cell Lymphoma

Diffuse large B cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma worldwide, constituting around 30-40% of all cases. Almost 60% of patients develop relapse of refractory DLBCL. Among the reasons for the therapy failure, tumour microenvironment (TME) components could be involved, including tumour-associated macrophages (TAMs), myeloid-derived suppressor cells (MDSCs), tumour-associated neutrophils (TANs), cancer-associated fibroblasts (CAFs), and different subtypes of cytotoxic CD8+ cells and T regulatory cells, which show complex interactions with tumour cells. Understanding of the TME can provide new therapeutic options for patients with DLBCL and improve their prognosis and overall survival. This review provides essentials of the latest understanding of tumour microenvironment elements and discusses their role in tumour progression and immune suppression mechanisms which result in poor prognosis for patients with DLBCL. In addition, we point out important markers for the diagnostic purposes and highlight novel therapeutic targets.

The roles of Th cells in myocardial infarction

Myocardial infarction, commonly known as a heart attack, is a serious condition caused by the abrupt stoppage of blood flow to a part of the heart, leading to tissue damage. A significant aspect of this condition is reperfusion injury, which occurs when blood flow is restored but exacerbates the damage. This review first addresses the role of the innate immune system, including neutrophils and macrophages, in the cascade of events leading to myocardial infarction and reperfusion injury. It then shifts focus to the critical involvement of CD4+ T helper cells in these processes. These cells, pivotal in regulating the immune response and tissue recovery, include various subpopulations such as Th1, Th2, Th9, Th17, and Th22, each playing a unique role in the pathophysiology of myocardial infarction and reperfusion injury. These subpopulations contribute to the injury process through diverse mechanisms, with cytokines such as IFN-γ and IL-4 influencing the balance between tissue repair and injury exacerbation. Understanding the interplay between the innate immune system and CD4+ T helper cells, along with their cytokines, is crucial for developing targeted therapies to mitigate myocardial infarction and reperfusion injury, ultimately improving outcomes for cardiac patients.

Causal relationships between circulating inflammatory cytokines and diabetic neuropathy: A Mendelian Randomization study

BACKGROUND

Emerging evidence suggests systemic inflammation as a critical mechanism underlying diabetic neuropathy. This study aimed to investigate the causal relationship between 41 circulating inflammatory cytokines and diabetic neuropathy.

METHODS

Summary statistics from previous Genome-Wide Association studies (GWAS) included pooled data on 41 inflammatory cytokines and diabetic neuropathy. A two-sample Mendelian Randomization (MR) design was employed, and the robustness of the results was confirmed through comprehensive sensitivity analyses.

RESULTS

Our study reveals that the linkage between increased levels of IFN_G (OR = 1.31, 95 %CI: 1.06-1.63; P = 0.014), IP_10 (OR = 1.18, 95 %CI: 1.01-1.36; P = 0.031) and an elevated risk of diabetic neuropathy. Conversely, higher levels of IL_9 (OR = 0.86, 95 %CI: 0.75-1.00; P = 0.048) and SCF (OR = 0.83, 95 %CI: 0.73-0.94; P = 0.003) are genetically determined to protect against diabetic neuropathy. Furthermore, the sensitivity analysis affirmed the results' dependability, revealing no heterogeneity or pleiotropy.

CONCLUSION

Our MR research identified four upstream inflammatory cytokines implicated in diabetic neuropathy. Overall, these findings suggest the potential for innovative therapeutic strategies. Further large-scale cohort studies are required for validation.

Elucidation of novel SNPs affecting immune response to classical swine fever vaccination in pigs using immunogenomics approach

The host genetic makeup plays a significant role in causing the within-breed variation among individuals after vaccination. The present study was undertaken to elucidate the genetic basis of differential immune response between high and low responder Landlly (Landrace X Ghurrah) piglets vis-à-vis CSF vaccination. For the purpose, E2 antibody response against CSF vaccination was estimated in sampled animals on the day of vaccination and 21-day post-vaccination as a measure of humoral immune response. Double-digestion restriction associated DNA (ddRAD) sequencing was undertaken on 96 randomly chosen Landlly piglets using Illumina HiSeq platform. SNP markers were called using standard methodology. Genome-wide association study (GWAS) was undertaken in PLINK program to identify the informative SNP markers significantly associated with differential immune response. The results revealed significant SNPs associated with E2 antibody response against CSF vaccination. The genome-wide informative SNPs for the humoral immune response against CSF vaccination were located on SSC10, SSC17, SSC9, SSC2, SSC3 and SSC6. The overlapping and flanking genes (500Kb upstream and downstream) of significant SNPs were CYB5R1, PCMTD2, WT1, IL9R, CD101, TMEM64, TLR6, PIGG, ADIPOR1, PRSS37, EIF3M, and DNAJC24. Functional enrichment and annotation analysis were undertaken for these genes in order to gain maximum insights into the association of these genes with immune system functionality in pigs. The genetic makeup was associated with differential immune response against CSF vaccination in Landlly piglets while the identified informative SNPs may be used as suitable markers for determining variation in host immune response against CSF vaccination in pigs.

TL1A priming induces a multi-cytokine Th9 cell phenotype that promotes robust allergic inflammation in murine models of asthma

The Th9 subset of T lymphocytes secretes the pleiotropic cytokine IL-9 which has functions in allergic airway disease, helminth infections, and tumor immunity. We and others have shown presence of Th cells that secrete IL-9 and type 2 cytokines in mouse and human allergic inflammation. However, the cytokines that promote a multi-cytokine secreting phenotype have not been defined. TNF superfamily members promote IL-9 production, and the TNF superfamily member TL1A signals through its receptor DR3 to potently increase IL-9. Here we demonstrate that TL1A increases expression of IL-9 and IL-13 as well as the frequency of IL-9 and IL-13 co-expressing cells in murine Th9 cell cultures, inducing a robust multi-cytokine phenotype. Mechanistically, this is linked to histone modifications allowing for increased accessibility at the Il9 and Il13 loci. We further show that TL1A alters the transcription factor network underlying expression of IL-9 and IL-13 in Th9 cells and increases binding of transcription factors to Il9 and Il13 loci. TL1A-priming enhances the pathogenicity of Th9 cells in murine models of allergic airway disease (AAD) through the increased expression of IL-9 and IL-13. Lastly, in both chronic and memory recall models of AAD, blockade of TL1A signaling decreases the multi-cytokine Th9 cell population and attenuates the allergic phenotype. Taken together, these data demonstrate that TL1A promotes the development of multi-cytokine Th9 cells that drive allergic airway diseases and that targeting pathogenic T helper cell-promoting cytokines could be an effective approach for modifying disease.

Biomarkers for response to TIL therapy: a comprehensive review

Adoptive cell therapy with tumor-infiltrating lymphocytes (TIL) has demonstrated durable clinical responses in patients with metastatic melanoma, substantiated by recent positive results of the first phase III trial on TIL therapy. Being a demanding and logistically complex treatment, extensive preclinical and clinical effort is required to optimize patient selection by identifying predictive biomarkers of response. This review aims to comprehensively summarize the current evidence regarding the potential impact of tumor-related factors (such as mutational burden, neoantigen load, immune infiltration, status of oncogenic driver genes, and epigenetic modifications), patient characteristics (including disease burden and location, baseline cytokines and lactate dehydrogenase serum levels, human leucocyte antigen haplotype, or prior exposure to immune checkpoint inhibitors and other anticancer therapies), phenotypic features of the transferred T cells (mainly the total cell count, CD8:CD4 ratio, ex vivo culture time, expression of exhaustion markers, costimulatory signals, antitumor reactivity, and scope of target tumor-associated antigens), and other treatment-related factors (such as lymphodepleting chemotherapy and postinfusion administration of interleukin-2).

Intratumoral Delivery of Interleukin 9 via Oncolytic Vaccinia Virus Elicits Potent Antitumor Effects in Tumor Models

The success of cancer immunotherapy is largely associated with immunologically hot tumors. Approaches that promote the infiltration of immune cells into tumor beds are urgently needed to transform cold tumors into hot tumors. Oncolytic viruses can transform the tumor microenvironment (TME), resulting in immunologically hot tumors. Cytokines are good candidates for arming oncolytic viruses to enhance their function in this transformation. Here, we used the oncolytic vaccinia virus (oVV) to deliver interleukin-9 (IL-9) into the tumor bed and explored its antitumor effects in colon and lung tumor models. Our data show that IL-9 prolongs viral persistence, which is probably mediated by the up-regulation of IL-10. The vvDD-IL-9 treatment elevated the expression of Th1 chemokines and antitumor factors such as IFN-γ, granzyme B, and perforin. IL-9 expression increased the percentages of CD4+ and CD8+ T cells in the TME and decreased the percentage of oVV-induced immune suppressive myeloid-derived suppressor cells (MDSC), leading to potent antitumor effects compared with parental virus treatment. The vvDD-IL-9 treatment also increased the percentage of regulatory T cells (Tregs) in the TME and elevated the expression of immune checkpoint molecules such as PD-1, PD-L1, and CTLA-4, but not GITR. The combination therapy of vvDD-IL-9 and the anti-CTLA-4 antibody, but not the anti-GITR antibody, induced systemic tumor-specific antitumor immunity and significantly extended the overall survival of mice, indicating a potential translation of the IL-9-expressing oncolytic virus into a clinical trial to enhance the antitumor effects elicited by an immune checkpoint blockade for cancer immunotherapy.

Toripalimab, a therapeutic monoclonal anti-PD-1 antibody with high binding affinity to PD-1 and enhanced potency to activate human T cells

Over the past decade, US Food and Drug Administration (FDA)-approved immune checkpoint inhibitors that target programmed death-1 (PD-1) have demonstrated significant clinical benefit particularly in patients with PD-L1 expressing tumors. Toripalimab is a humanized anti-PD-1 antibody, approved by FDA for first-line treatment of nasopharyngeal carcinoma in combination with chemotherapy. In a post hoc analysis of phase 3 studies, toripalimab in combination with chemotherapy improved overall survival irrespective of PD-L1 status in nasopharyngeal carcinoma (JUPITER-02), advanced non-small cell lung cancer (CHOICE-01) and advanced esophageal squamous cell carcinoma (JUPITER-06). On further characterization, we determined that toripalimab is molecularly and functionally differentiated from pembrolizumab, an anti-PD-1 mAb approved previously for treating a wide spectrum of tumors. Toripalimab, which binds the FG loop of PD-1, has 12-fold higher binding affinity to PD-1 than pembrolizumab and promotes significantly more Th1- and myeloid-derived inflammatory cytokine responses in healthy human PBMCs in vitro. In an ex vivo system employing dissociated tumor cells from treatment naïve non-small cell lung cancer patients, toripalimab induced several unique genes in IFN-γ and immune cell pathways, showed different kinetics of activation and significantly enhanced IFN-γ signature. Additionally, binding of toripalimab to PD-1 induced lower levels of SHP1 and SHP2 recruitment, the negative regulators of T cell activation, in Jurkat T cells ectopically expressing PD-1. Taken together, these data demonstrate that toripalimab is a potent anti-PD-1 antibody with high affinity PD-1 binding, strong functional attributes and demonstrated clinical activity that encourage its continued clinical investigation in several types of cancer.

ADGRE5-centered Tsurv model in T cells recognizes responders to neoadjuvant cancer immunotherapy

Background

Neoadjuvant immunotherapy with anti-programmed death-1 (neo-antiPD1) has revolutionized perioperative methods for improvement of overall survival (OS), while approaches for major pathologic response patients' (MPR) recognition along with methods for overcoming non-MPR resistance are still in urgent need.

Methods

We utilized and integrated publicly-available immune checkpoint inhibitors regimens (ICIs) single-cell (sc) data as the discovery datasets, and innovatively developed a cell-communication analysis pipeline, along with a VIPER-based-SCENIC process, to thoroughly dissect MPR-responding subsets. Besides, we further employed our own non-small cell lung cancer (NSCLC) ICIs cohort's sc data for validation in-silico. Afterward, we resorted to ICIs-resistant murine models developed by us with multimodal investigation, including bulk-RNA-sequencing, Chip-sequencing and high-dimensional cytometry by time of flight (CYTOF) to consolidate our findings in-vivo. To comprehensively explore mechanisms, we adopted 3D ex-vivo hydrogel models for analysis. Furthermore, we constructed an ADGRE5-centered Tsurv model from our discovery dataset by machine learning (ML) algorithms for a wide range of tumor types (NSCLC, melanoma, urothelial cancer, etc.) and verified it in peripheral blood mononuclear cells (PBMCs) sc datasets.

Results

Through a meta-analysis of multimodal sequential sc sequencing data from pre-ICIs and post-ICIs, we identified an MPR-expanding T cells meta-cluster (MPR-E) in the tumor microenvironment (TME), characterized by a stem-like CD8+ T cluster (survT) with STAT5-ADGRE5 axis enhancement compared to non-MPR or pre-ICIs TME. Through multi-omics analysis of murine TME, we further confirmed the existence of survT with silenced function and immune checkpoints (ICs) in MPR-E. After verification of the STAT5-ADGRE5 axis of survT in independent ICIs cohorts, an ADGRE5-centered Tsurv model was then developed through ML for identification of MPR patients pre-ICIs and post-ICIs, both in TME and PBMCs, which was further verified in pan-cancer immunotherapy cohorts. Mechanistically, we unveiled ICIs stimulated ADGRE5 upregulation in a STAT5-IL32 dependent manner in a 3D ex-vivo system (3D-HYGTIC) developed by us previously, which marked Tsurv with better survival flexibility, enhanced stemness and potential cytotoxicity within TME.

Conclusion

Our research provides insights into mechanisms underlying MPR in neo-antiPD1 and a well-performed model for the identification of non-MPR.

Genome and proteomic analysis of risk factors for fatal outcome in children with severe community-acquired pneumonia caused by human adenovirus 7

INTRODUCTION

Human adenovirus 7 (HAdV-7) is an important viral pathogen of severe pneumonia in children and a serious threat to health.

METHODS

A cohort of 45 pediatric patients diagnosed with HAdV-7-associated severe pneumonia and admitted to the Pediatric Intensive Care Unit at the Children's Hospital of Chongqing Medical University from May 2018 to January 2020 were included. Risk factors of death were analyzed by the Cox proportional risk mode with Clinical data, serum, and nasopharyngeal aspirate adenovirus load, Genome analysis, Olink proteomics, and cytokine profile between dead and surviving patients were also analyzed.

RESULTS

A total of 45 children with a median age of 12.0 months (interquartile range [IQR]: 6.5, 22.0) were included (female 14), including 14 (31.1%) who died. High serum viral load was an independent risk factor for mortality (hazard ratio [HR] = 2.16, 95% confidence interval [CI], 1.04-4.49, p = 0.039). BTB and CNC homology 1 (BACH1), interleukin-5 (IL-5), and IL-9 levels were significantly correlated with serum viral load (p = 0.0400, 0.0499, and 0.0290; r = 0.4663, 0.3339, and -0.3700, respectively), with significant differences between the dead and survival groups (p = 0.021, 0.001, and 0.021).

CONCLUSIONS

Severe cytokine storm-associated high serum viral load after HAdV-7 infection may be the main mechanism responsible for poor prognosis in children.

Comparison of serum 25(OH) vitamin D, parathormone and immunity marker concentrations between dogs with transmissible venereal tumour and healthy dogs

BACKGROUND

1,25-Dihydroxyvitamin D (1,25(OH)2 D) is vital in the homeostasis of calcium and bone health as well as in the prevention of many disorders such as neoplasms. Epidemiological data show that low concentrations of both 1,25(OH)2 D and its precursor 25(OH) vitamin D (25(OH)D) are associated with an increased risk of a variety of human tumours.

OBJECTIVES

To investigate 25(OH)D, parathormone (PTH) and immunity marker concentrations in dogs with transmissible venereal tumour (TVT).

METHODS

25(OH)D, PTH and various biochemical and immunity markers were evaluated in dogs with TVT (n = 26) and in healthy (n = 30) dogs.

RESULTS

25(OH)D concentrations were significantly lower in dogs with TVT in comparison with healthy dogs. In contrast, PTH, immunoglobulin G and interleukin (IL)-9 concentrations were higher in the dogs with TVT. Other variables, including IL-10, interferon γ, calcium and inorganic phosphate, were not statistically different between the two groups.

CONCLUSIONS

Decreased serum 25(OH)D concentration may be a risk factor for the development of canine TVT; however, cause-and-effect remains incompletely understood. Further studies are required to elucidate the exact role of 25(OH)D in canine TVT and whether vitamin D supplementation may be useful prophylactically or as an adjunct to chemotherapy.

The World according to IL-9

Among the cytokines regulating immune cells, IL-9 has gained considerable attention for its ability to act on multiple cell types as a regulator of beneficial and pathologic immune responses. Yet, it is still not clearly defined how IL-9 impacts immune responses. IL-9 demonstrates a remarkable degree of tissue-specific functionality and has cellular sources that vary by tissue site and the context of the inflammatory milieu. Here, we provide perspective to summarize the biological activities of IL-9 and highlight cell type-specific roles in the immune pathogenesis of diseases. This perspective will be important in defining the diseases where targeting IL-9 as a therapeutic strategy would be beneficial and where it has the potential to complicate clinical outcomes.

Upregulated Expression of the IL-9 Receptor on TRAF3-Deficient B Lymphocytes Confers Ig Isotype Switching Responsiveness to IL-9 in the Presence of Antigen Receptor Engagement and IL-4

The pleiotropic cytokine IL-9 signals to target cells by binding to a heterodimeric receptor consisting of the unique subunit IL-9R and the common subunit γ-chain shared by multiple cytokines of the γ-chain family. In the current study, we found that the expression of IL-9R was strikingly upregulated in mouse naive follicular B cells genetically deficient in TNFR-associated factor 3 (TRAF3), a critical regulator of B cell survival and function. The highly upregulated IL-9R on Traf3-/- follicular B cells conferred responsiveness to IL-9, including IgM production and STAT3 phosphorylation. Interestingly, IL-9 significantly enhanced class switch recombination to IgG1 induced by BCR crosslinking plus IL-4 in Traf3-/- B cells, which was not observed in littermate control B cells. We further demonstrated that blocking the JAK-STAT3 signaling pathway abrogated the enhancing effect of IL-9 on class switch recombination to IgG1 induced by BCR crosslinking plus IL-4 in Traf3-/- B cells. Our study thus revealed, to our knowledge, a novel pathway that TRAF3 suppresses B cell activation and Ig isotype switching by inhibiting IL-9R-JAK-STAT3 signaling. Taken together, our findings provide (to our knowledge) new insights into the TRAF3-IL-9R axis in B cell function and have significant implications for the understanding and treatment of a variety of human diseases involving aberrant B cell activation such as autoimmune disorders.

Assessment of Impact of Human Leukocyte Antigen-Type and Cytokine-Type Responses on Outcomes after Targeted Therapy Currently Used to Treat Chronic Lymphocytic Leukemia

Tumor growth and metastasis are reliant on intricate interactions between the host immune system and various counter-regulatory immune escape mechanisms employed by the tumor. Tumors can resist immune surveillance by modifying the expression of human leukocyte antigen (HLA) molecules, which results in the impaired presentation of tumor-associated antigens, subsequently evading detection and destruction by the immune system. The management of chronic lymphocytic leukemia (CLL) is based on symptom severity and includes various types of targeted therapies, including rituximab, obinutuzumab, ibrutinib, acalabrutinib, zanubrutinib, idelalisib, and venetoclax. These therapies rely on the recognition of specific peptides presented by HLAs on the surface of tumor cells by T cells, leading to an immune response. HLA class I molecules are found in most human cell types and interact with T-cell receptors (TCRs) to activate T cells, which play a vital role in inducing adaptive immune responses. However, tumor cells may evade T-cell attack by downregulating HLA expression, limiting the efficacy of HLA-dependent immunotherapy. The prognosis of CLL largely depends on the presence or absence of genetic abnormalities, such as del(17p), TP53 point mutations, and IGHV somatic hypermutation status. These oral targeted therapies alone or in combination with anti-CD20 antibodies have replaced chemoimmunotherapy as the primary treatment for CLL. In this review, we summarize the current clinical evidence on the impact of HLA- and cytokine-type responses on outcomes after targeted therapies currently used to treat CLL.

Amphiregulin/epidermal growth factor receptor/hypoxia-inducible factor-1α pathway regulates T helper 9 and T cytotoxic 9 cell response in adult patients with infectious mononucleosis

Amphiregulin (AREG)/epidermal growth factor receptor (EGFR) signaling induces hypoxia-inducible factor-1α (HIF-1α), leading to promotion of T helper 9 (Th9) differentiation and anti-tumor functions. However, the role of the AREG/EGFR/HIF-1α pathway in regulating interleukin-9 (IL-9) production by T cells in adult patients with infectious mononucleosis (IM) has not been fully elucidated. Fifty IM patients and 20 controls were enrolled. The percentages of Th9 and T cytotoxic 9 (Tc9) cells, the mRNA relative expressions of the transcription factors of IL-9-secreting T cells, purine-rich nucleic acid binding protein 1 (PU.1) and forkhead box protein O1 (FOXO1), and the levels of IL-9, AREG, EGFR, and HIF-1α were measured. Peripheral blood mononuclear cells from IM patients were stimulated with EGFR inhibitor or exogenous AREG in the presence or absence of anti-HIF-1α. Regulation of the AREG/EGFR/HIF-1α pathway to IL-9 production by T cells was assessed. The percentages of Th9 and Tc9 cells, plasma IL-9 levels, and PU.1 and FOXO1 mRNA expressions were elevated in IM patients. Plasma levels of AREG and HIF-1α were also increased in IM patients. AREG levels correlated positively with the percentages of Th9 and Tc9 cells in IM patients. Inhibition of EGFR suppressed IL-9-producing T cell differentiation and HIF-1α production. Exogenous AREG stimulation not only induced EGFR and HIF-1α expression but also promoted IL-9-secreting T cell differentiation. Neutralization of HIF-1α abrogated AREG/EGFR-induced Th9 and Tc9 differentiation in IM patients. The current data suggested that the AREG/EGFR/HIF-1α pathway contributed to the elevation of Th9 and Tc9 differentiation in IM patients.

Distinct systemic immune networks define severe vs. mild COVID-19 in hematologic and solid cancer patients

Introduction

The COVID-19 pandemic, caused by the coronavirus SARS-CoV-2, has impacted health across all sectors of society. A cytokine-release syndrome, combined with an inefficient response of innate immune cells to directly combat the virus, characterizes the severe form of COVID-19. While immune factors involved in the development of severe COVID-19 in the general population are becoming clearer, identification of the immune mechanisms behind severe disease in oncologic patients remains uncertain.

Methods

Here we evaluated the systemic immune response through the analysis of soluble blood immune factors and anti-SARS-CoV-2 antibodies within the early days of a positive SARS-CoV-2 diagnostic in oncologic patients.

Results

Individuals with hematologic malignancies that went on to die from COVID-19 displayed at diagnosis severe leukopenia, low antibody production against SARS-CoV-2 proteins, and elevated production of innate immune cell recruitment and activation factors. These patients also displayed correlation networks in which IL-2, IL-13, TNF-alpha, IFN-gamma, and FGF2 were the focal points. Hematologic cancer patients that showed highly networked and coordinated anti-SARS-CoV-2 antibody production, with central importance of IL-4, IL-5, IL-12A, IL-15, and IL-17A, presented only mild COVID-19. Conversely, solid tumor patients that had elevated levels of inflammatory cytokines IL-6, CXCL8, and lost the coordinate production of anti-virus antibodies developed severe COVID-19 and died. Patients that displayed positive correlation networks between anti-virus antibodies, and a regulatory axis involving IL-10 and inflammatory cytokines recovered from the disease. We also provided evidence that CXCL8 is a strong predictor of death for oncologic patients and could be an indicator of poor prognosis within days of the positive diagnostic of SARS-CoV-2 infection.

Conclusion

Our findings defined distinct systemic immune profiles associated with COVID-19 clinical outcome of patients with cancer and COVID-19. These systemic immune networks shed light on potential immune mechanisms involved in disease outcome, as well as identify potential clinically useful biomarkers.

The Cytokine Network in Colorectal Cancer: Implications for New Treatment Strategies

Colorectal cancer (CRC) is one of the most frequent tumor entities worldwide with only limited therapeutic options. CRC is not only a genetic disease with several mutations in specific oncogenes and/or tumor suppressor genes such as APC, KRAS, PIC3CA, BRAF, SMAD4 or TP53 but also a multifactorial disease including environmental factors. Cancer cells communicate with their environment mostly via soluble factors such as cytokines, chemokines or growth factors to generate a favorable tumor microenvironment (TME). The TME, a heterogeneous population of differentiated and progenitor cells, plays a critical role in regulating tumor development, growth, invasion, metastasis and therapy resistance. In this context, cytokines from cancer cells and cells of the TME influence each other, eliciting an inflammatory milieu that can either enhance or suppress tumor growth and metastasis. Additionally, several lines of evidence exist that the composition of the microbiota regulates inflammatory processes, controlled by cytokine secretion, that play a role in carcinogenesis and tumor progression. In this review, we discuss the cytokine networks between cancer cells and the TME and microbiome in colorectal cancer and the related treatment strategies, with the goal to discuss cytokine-mediated strategies that could overcome the common therapeutic resistance of CRC tumors.

Longitudinal transcriptome analysis of cattle infected with Theileria parva

The apicomplexan cattle parasite Theileria parva is a major barrier to improving the livelihoods of smallholder farmers in Africa, killing over one million cattle on the continent each year. Although exotic breeds not native to Africa are highly susceptible to the disease, previous studies have illustrated that such breeds often show innate tolerance to infection by the parasite. The mechanisms underlying this tolerance remain largely unclear. To better understand the host response to T. parva infection we characterised the transcriptional response over 15 days in tolerant and susceptible cattle (n = 29) naturally exposed to the parasite. We identify key genes and pathways activated in response to infection as well as, importantly, several genes differentially expressed between the animals that ultimately survived or succumbed to infection. These include genes linked to key cell proliferation and infection pathways. Furthermore, we identify response expression quantitative trait loci containing genetic variants whose impact on the expression level of nearby genes changes in response to the infection. These therefore provide an indication of the genetic basis of differential host responses. Together these results provide a comprehensive analysis of the host transcriptional response to this under-studied pathogen, providing clues as to the mechanisms underlying natural tolerance to the disease.

Grace-AKO: a novel and stable knockoff filter for variable selection incorporating gene network structures

Motivation

Variable selection is a common statistical approach to identifying genes associated with clinical outcomes of scientific interest. There are thousands of genes in genomic studies, while only a limited number of individual samples are available. Therefore, it is important to develop a method to identify genes associated with outcomes of interest that can control finite-sample false discovery rate (FDR) in high-dimensional data settings.

Results

This article proposes a novel method named Grace-AKO for graph-constrained estimation (Grace), which incorporates aggregation of multiple knockoffs (AKO) with the network-constrained penalty. Grace-AKO can control FDR in finite-sample settings and improve model stability simultaneously. Simulation studies show that Grace-AKO has better performance in finite-sample FDR control than the original Grace model. We apply Grace-AKO to the prostate cancer data in The Cancer Genome Atlas program by incorporating prostate-specific antigen (PSA) pathways in the Kyoto Encyclopedia of Genes and Genomes as the prior information. Grace-AKO finally identifies 47 candidate genes associated with PSA level, and more than 75% of the detected genes can be validated.

Opposing functions of circadian protein DBP and atypical E2F family E2F8 in anti-tumor Th9 cell differentiation

Interleukin-9 (IL-9)-producing CD4⁺ T helper cells (Th9) have been implicated in allergy/asthma and anti-tumor immunity, yet molecular insights on their differentiation from activated T cells, driven by IL-4 and transforming growth factor-beta (TGF-β), is still lacking. Here we show opposing functions of two transcription factors, D-binding protein (DBP) and E2F8, in controlling Th9 differentiation. Specifically, TGF-β and IL-4 signaling induces phosphorylation of the serine 213 site in the linker region of the Smad3 (pSmad3L-Ser²¹³) via phosphorylated p38, which is necessary and sufficient for Il9 gene transcription. We identify DBP and E2F8 as an activator and repressor, respectively, for Il9 transcription by pSmad3L-Ser²¹³. Notably, Th9 cells with siRNA-mediated knockdown for Dbp or E2f8 promote and suppress tumor growth, respectively, in mouse tumor models. Importantly, DBP and E2F8 also exhibit opposing functions in regulating human TH9 differentiation in vitro. Thus, our data uncover a molecular mechanism of Smad3 linker region-mediated, opposing functions of DBP and E2F8 in Th9 differentiation.

Cytokine profiling in plasma distinguishes the histological inflammatory subtype of head and neck squamous cell carcinoma and a novel regulatory role of osteopontin

Head and neck squamous cell carcinoma (HNSCC) can be classified according to the histological inflammatory subtype (HIS) into inflamed (HIS-INF) or immune excluded (HIS-IE). HIS-IE was previously associated with higher levels of soluble Semaphorin 4D (HsS4D) in plasma, and higher transcriptional levels of osteopontin (OPN) in the tumor tissue, compared to HIS-INF. The goal of the current study is to investigate whether the HIS inflammatory subtype can be distinguished by a differential cytokine panel in peripheral blood. Retrospectively collected five HIS-INF and five HIS-IE tumor tissue with paired plasma were included in the study. Five healthy donors (HD) and five autoimmune/chronic inflammatory conditions (AI/CI) were controls. The ELISA-Luminex™ system was used to detect 40 traditional cytokines in plasma. Human cytokine array (104 cytokines) was used for the conditioned medium (CM) of the HNSCC HN6 cell line. Semaphorin 4D (Sema4D) siRNA and recombinant human osteopontin (rh-OPN) were used to investigate the effect of OPN on Sema4D expression. The HIS-IE cytokine profile was higher than HIS-INF but comparable to AI/CI. HIS-INF had the lowest cytokine levels. HIS-IE was differentially higher in IP-10 and IL8 compared to HD, while HIS-INF was higher in IL-10. Sema4D inhibition in HN6 resulted in a decrease of OPN in the CM of HN6, and treatment with rh-OPN rescued Sema4D in HN6 cell lysate and associated CM. In conclusion, the current work demonstrates a novel association between the HIS subtypes and a differential pattern of cytokine expression in plasma. These findings can open new avenues for HNSCC patient stratification and hence provide better personalized treatment.

Molecules involved in the development of Barrett's esophagus phenotype in chronic eosinophilic esophagitis

This paper aims to investigate the molecules involved in development of Barrett's esophagus (BE) in human eosinophilic esophagitis (EoE). Histopathological, immunohistochemical, real-time PCR Immuno blot, and ELISA analyses are performed to identify the signature genes and proteins involved in the progression of BE in EoE. We detected characteristic features of BE like intermediate columnar-type epithelial cells, induced BE signature genes like ErbB3, CDX1, ErbB2IP in the esophageal mucosa of patients with EoE. In addition, we had observed several BE-associated proteins such as TFF3, p53 and the progression markers like EGFR, p16, MICA, MICB, and MHC molecules in esophageal biopsies of patients with chronic EoE. Interestingly, we also detected mucin-producing columnar cells and MUC-2, MUC-4, and MUC5AC genes and proteins along with induced IL-9 in patients with chronic EoE. A strong correlation of IL-9 with mucin genes is observed that implicated a possible role for IL-9 in the transformation of esophageal squamous epithelial cells to columnar epithelial cells in patients with EoE. These findings indicate that IL-9 may have an important role in BE development in patients with chronic EoE. We also discovered that IL-9 stimulates mucin-producing and barrier cell transcripts and proteins such CK8/18, GATA4, SOX9, TFF1, MUC5AC, and tight junction proteins in primary esophageal epithelial cells when exposed to IL-9. Taken together, these findings provide evidence that indeed IL-9 has a role in the initiation and progression of BE characteristics like development of mucin-producing columnar epithelial cells in patients with chronic EoE.NEW & NOTEWORTHY Intermediate columnar-type epithelial cells are observed in biopsies of patients with EoE. Induced BE signature genes (CK8/18, CDX1 GATA4, SOX9, and Occludin) were observed in patients with chronic EoE. Induction of IL-9 and its correlation with eosinophils mucin-producing genes and proteins was observed in patients with EoE. Induced IL-9 may be responsible for the development of BE in patients with chronic EoE.

First Characterization of Chicken Interleukin-9

Interleukin-9 (IL-9) is a pleiotropic cytokine that acts on a variety of cells and tissues, and plays roles in inflammation and infection as well as tumor immunity. While mammalian IL-9s have been widely investigated, avian IL-9 has not yet been identified and characterized. In this study, we cloned chicken IL-9 (chIL-9) and performed a phylogenetic analysis, examined its tissue distribution, characterized the biological functions of recombinant chIL-9 (rchIL-9) and the expression form of natural chIL-9. Phylogenetic analysis showed that chIL-9 has less than 30% amino acid identity with mammalian IL-9s. The chIL-9 mRNA can be abundantly detected only in the testis and thymus, and are significantly up-regulated in peripheral blood mononuclear cells (PBMCs) upon mitogen stimulation. The rchIL-9 was produced by prokaryotic and eukaryotic expression systems and showed biological activity in activating monocytes/macrophages to produce inflammatory cytokines and promoting the proliferation of CD3⁺ T cells. In addition, four monoclonal antibodies (mAbs) and rabbit polyclonal antibody (pAb) against rchIL-9 were generated. Using anti-chIL-9 mAbs and pAb, natural chIL-9 expressed by the activated PBMCs of chickens with a molecular weight of 25kD was identified by Western-blotting. Collectively, our study reveals for the first time the presence of functional IL-9 in birds and lays the ground for further investigating the roles of chIL-9 in diseases and immunity.

Chemokines and chemokine receptors in colorectal cancer; multifarious roles and clinical impact

Colorectal cancer (CRC) is considered the second cause of cancer death worldwide. The early diagnosis plays a key role in patient prognosis and subsequently overall survival. Similar to several types of cancer, colorectal cancer is also characterised by drug resistance and heterogeneity that contribute to its complexity -especially at advanced stages. However, despite the extensive research related to the identification of biomarkers associated to early diagnosis, accurate prognosis and the management of CRC patients, little progress has been made thus far. Therefore, the mortality rates, especially at advanced stages, remain high. A large family of chemoattractant cytokines called chemokines are known for their significant role in inflammation and immunity. Chemokines released by the different tumorous cells play a key role in increasing the complexity of the tumour's microenvironment. The current review investigates the role of chemokines and chemokine receptors in colorectal cancer and their potential as clinical molecular signatures that could be effectively used as a personalised therapeutic approach. We discussed how chemokine and chemokine receptors regulate the microenvironment and lead to heterogeneity in CRC. An important aspect of chemokines is their role in drug resistance which has been extensively discussed. This review also provides an overview of the current advances in the search for chemokines and chemokine receptors in CRC.

The Emerging Role of Cyclin-Dependent Kinase Inhibitors in Treating Diet-Induced Obesity: New Opportunities for Breast and Ovarian Cancers?

Overweight and obesity constitute the most impactful lifestyle-dependent risk factors for cancer and have been tightly linked to a higher number of tumor-related deaths nowadays. The excessive accumulation of energy can lead to an imbalance in the level of essential cellular biomolecules that may result in inflammation and cell-cycle dysregulation. Nutritional strategies and phytochemicals are gaining interest in the management of obesity-related cancers, with several ongoing and completed clinical studies that support their effectiveness. At the same time, cyclin-dependent kinases (CDKs) are becoming an important target in breast and ovarian cancer treatment, with various FDA-approved CDK4/6 inhibitors that have recently received more attention for their potential role in diet-induced obesity (DIO). Here we provide an overview of the most recent studies involving nutraceuticals and other dietary strategies affecting cell-cycle pathways, which might impact the management of breast and ovarian cancers, as well as the repurposing of already commercialized chemotherapeutic options to treat DIO.

Cannabidiolic acid in Hemp Seed Oil Table Spoon and Beyond

Cannabidiolic acid (CBDA) is the main precannabinoid in industrial hemp. It represents a common constituent of hemp seed oil, but mainly abundant in the aerial parts of the plant (including their processing waste). Thus, the optimization of fast and low-cost purification strategies is mandatory, as well as a deep investigation on its nutraceutical and cosmeceutical properties. To this purpose, CBDA content in hemp seed oil is evaluated, and its recovery from wasted leaves is favorably achieved. The cytotoxicity screening towards HaCaT cells, by means of MTT, SRB and LDH release assays, suggested it was not able to decrease cell viability or perturb cell integrity up to 10 μM concentration. Thus, the ability of CBDA to differentially modulate the release of proinflammatory cytokines and chemokines mediators has been evaluated, finding that CBDA decreased IFN-γ, CXCL8, CXCL10, CCL2, CCL4 and CCL5, mostly in a dose-dependent manner, with 10 μM tested concentration exerting the highest activity. These data, together with those from assessing antimicrobial activity against Gram(+) and Gram(−) bacteria and the antibiofilm formation, suggest that CBDA is able to counteract the inflammatory response, also preventing bacteria colonization.

Venom of the desert black snake Walterinnesia aegyptia enhances anti-tumor immunity via its beneficial modulatory effects on pro- and anti-tumorigenic inflammatory mediators in cultured colon cancer cells

The role of inflammation in colon cancer is understood as a well-accepted factor that has the tendency to release multiple pro- and anti-tumorigenic inflammatory mediators. Inflammation-induced increased expression of anti-tumorigenic inflammatory mediators and decreased expression of pro-tumorigenic inflammatory mediators encourage beneficial inflammatory effects in terms of powerful anti-tumor immunity. The present study aims to screen the beneficial inflammatory effects of Walterinnesia aegyptia venom via determining its modulatory tendency on the expression of 40 pro- and anti-tumorigenic inflammatory mediators (cytokines/growth factors/chemokines) in LoVo human colon cancer cell line. LoVo-cells were treated with varying doses of crude venom of W. aegyptia. Cell viability was checked utilizing flow cytometry, and IC50 of venom was determined. Venom-induced inflammatory effects were evaluated on the expression of 40 different inflammatory mediators (12 anti-tumorigenic cytokines, 11 pro-tumorigenic cytokines, 7 pro-tumorigenic growth factors, 9 pro-tumorigenic chemokines and 1 anti-tumorigenic chemokine) in treated LoVo-cells [utilizing enzyme-linked immunosorbent assay (ELISA)] and compared with controls. Treatment of venom induced significant cytotoxic effects on inflamed LoVo-cells. IC50 treatment of venom caused significant modulations on the expression of 22 inflammatory mediators in treated LoVo-cells. The beneficial modulatory effects of venom were screened via its capability to significantly increase the expression of five powerful anti-tumorigenic mediators (IL-9, IL-12p40, IL-15, IL-1RA and Fractalkine) and decrease the expression of four major pro-tumorigenic mediators (IL-1β, VEGF, MCP-1 and MCP-3). Walterinnesia aegyptia venom-induced beneficial modulations on the expression of nine crucial pro/anti-tumorigenic inflammatory mediators can be effectively used to enhance powerful anti-tumor immunity against colon cancer.

Interleukin (IL)-9 Supports the Tumor-Promoting Environment of Chronic Lymphocytic Leukemia

Simple Summary

Interleukin 9 (IL-9), a soluble factor secreted by immune cells, has been found in several tumor niches where, depending on the specific tumor type, it either promotes or counteracts tumor development. Recently, IL-9 has been implicated in the development of chronic lymphocytic leukemia, although the underlying molecular mechanism remains unknown. Here, we summarize the current knowledge concerning the roles of IL-9 in disease, with a focus on its implication in the pathogenesis of chronic lymphocytic leukemia.

Abstract

Interleukin (IL)-9 is a soluble factor secreted by immune cells into the microenvironment. Originally identified as a mediator of allergic responses, IL-9 has been detected in recent years in several tumor niches. In solid tumors, it mainly promotes anti-tumor immune responses, while in hematologic malignancies, it sustains the growth and survival of neoplastic cells. IL-9 has been recently implicated in the pathogenesis of chronic lymphocytic leukemia; however, the molecular mechanisms underlying its contribution to this complex neoplasia are still unclear. Here, we summarize the current knowledge of IL-9 in the tumor microenvironment, with a focus on its role in the pathogenesis of chronic lymphocytic leukemia.

γδ T Cells for Leukemia Immunotherapy: New and Expanding Trends

Recently, many discoveries have elucidated the cellular and molecular diversity in the leukemic microenvironment and improved our knowledge regarding their complex nature. This has allowed the development of new therapeutic strategies against leukemia. Advances in biotechnology and the current understanding of T cell-engineering have led to new approaches in this fight, thus improving cell-mediated immune response against cancer. However, most of the investigations focus only on conventional cytotoxic cells, while ignoring the potential of unconventional T cells that until now have been little studied. γδ T cells are a unique lymphocyte subpopulation that has an extensive repertoire of tumor sensing and may have new immunotherapeutic applications in a wide range of tumors. The ability to respond regardless of human leukocyte antigen (HLA) expression, the secretion of antitumor mediators and high functional plasticity are hallmarks of γδ T cells, and are ones that make them a promising alternative in the field of cell therapy. Despite this situation, in particular cases, the leukemic microenvironment can adopt strategies to circumvent the antitumor response of these lymphocytes, causing their exhaustion or polarization to a tumor-promoting phenotype. Intervening in this crosstalk can improve their capabilities and clinical applications and can make them key components in new therapeutic antileukemic approaches. In this review, we highlight several characteristics of γδ T cells and their interactions in leukemia. Furthermore, we explore strategies for maximizing their antitumor functions, aiming to illustrate the findings destined for a better mobilization of γδ T cells against the tumor. Finally, we outline our perspectives on their therapeutic applicability and indicate outstanding issues for future basic and clinical leukemia research, in the hope of contributing to the advancement of studies on γδ T cells in cancer immunotherapy.

Gene-Edited Interleukin CAR-T Cells Therapy in the Treatment of Malignancies: Present and Future

In recent years, chimeric antigen receptor T cells (CAR-T cells) have been faced with the problems of weak proliferation and poor persistence in the treatment of some malignancies. Researchers have been trying to perfect the function of CAR-T by genetically modifying its structure. In addition to the participation of T cell receptor (TCR) and costimulatory signals, immune cytokines also exert a decisive role in the activation and proliferation of T cells. Therefore, genetic engineering strategies were used to generate cytokines to enhance tumor killing function of CAR-T cells. When CAR-T cells are in contact with target tumor tissue, the proliferation ability and persistence of T cells can be improved by structurally or inductively releasing immunoregulatory molecules to the tumor region. There are a large number of CAR-T cells studies on gene-edited cytokines, and the most common cytokines involved are interleukins (IL-7, IL-12, IL-15, IL-18, IL-21, IL-23). Methods for the construction of gene-edited interleukin CAR-T cells include co-expression of single interleukin, two interleukin, interleukin combined with other cytokines, interleukin receptors, interleukin subunits, and fusion inverted cytokine receptors (ICR). Preclinical and clinical trials have yielded positive results, and many more are under way. By reading a large number of literatures, we summarized the functional characteristics of some members of the interleukin family related to tumor immunotherapy, and described the research status of gene-edited interleukin CAR-T cells in the treatment of malignant tumors. The objective is to explore the optimized strategy of gene edited interleukin-CAR-T cell function.

Tumor rejection in Cblb -/- mice depends on IL-9 and Th9 cells

BACKGROUND

Casitas B lymphoma-b (Cbl-b) is a central negative regulator of cytotoxic T and natural killer (NK) cells and functions as an intracellular checkpoint in cancer. In particular, Th9 cells support mast cell activation, promote dendritic cell recruitment, enhance the cytolytic function of cytotoxic T lymphocytes and NK cells, and directly kill tumor cells, thereby contributing to tumor immunity. However, the role of Cbl-b in the differentiation and antitumor function of Th9 cells is not sufficiently resolved.

METHODS

Using Cblb ^-/- mice, we investigated the effect of knocking out Cblb on the differentiation process and function of different T helper cell subsets, focusing on regulatory T cell (Treg) and Th9 cells. We applied single-cell RNA (scRNA) sequencing of in vitro differentiated Th9 cells to understand how Cbl-b shapes the transcriptome and regulates the differentiation and function of Th9 cells. We transferred tumor-model antigen-specific Cblb ^-/- Th9 cells into melanoma-bearing mice and assessed tumor control in vivo. In addition, we blocked interleukin (IL)-9 in melanoma cell-exposed Cblb ^-/- mice to investigate the role of IL-9 in tumor immunity.

RESULTS

Here, we provide experimental evidence that Cbl-b acts as a rheostat favoring Tregs at the expense of Th9 cell differentiation. Cblb ^-/- Th9 cells exert superior antitumor activity leading to improved melanoma control in vivo. Accordingly, blocking IL-9 in melanoma cell-exposed Cblb ^-/- mice reversed their tumor rejection phenotype. Furthermore, scRNA sequencing of in vitro differentiated Th9 cells from naïve T cells isolated from wildtype and Cblb ^-/- animals revealed a transcriptomic basis for increased Th9 cell differentiation.

CONCLUSION

We established IL-9 and Th9 cells as key antitumor executers in Cblb ^-/- animals. This knowledge may be helpful for the future improvement of adoptive T cell therapies in cancer.

The Janus Face of IL-33 Signaling in Tumor Development and Immune Escape

Simple Summary

Interleukin-33 (IL-33) is often released from damaged cells, acting as a danger signal. IL-33 exerts its function by interacting with its receptor suppression of tumorigenicity 2 (ST2) that is constitutively expressed on most immune cells. Therefore, IL-33/ST2 signaling can modulate immune responses to participate actively in a variety of pathological conditions, such as cancer. Like a two-faced Janus, which faces opposite directions, IL-33/ST2 signaling may play contradictory roles on its impact on cancer progression through both immune and nonimmune cellular components. Accumulating evidence demonstrates both pro- and anti-tumorigenic properties of IL-33, depending on the complex nature of different tumor immune microenvironments. We summarize and discuss the most recent studies on the contradictory effects of IL-33 on cancer progression and treatment, with a goal to better understanding the various ways for IL-33 as a therapeutic target.

Abstract

Interleukin-33 (IL-33), a member of the IL-1 cytokine family, plays a critical role in maintaining tissue homeostasis as well as pathological conditions, such as allergy, infectious disease, and cancer, by promoting type 1 and 2 immune responses. Through its specific receptor ST2, IL-33 exerts multifaceted functions through the activation of diverse intracellular signaling pathways. ST2 is expressed in different types of immune cells, including Th2 cells, Th1 cells, CD8⁺ T cells, regulatory T cells (T_reg), cytotoxic NK cells, group 2 innate lymphoid cells (ILC2s), and myeloid cells. During cancer initiation and progression, the aberrant regulation of the IL-33/ST2 axis in the tumor microenvironment (TME) extrinsically and intrinsically mediates immune editing via modulation of both innate and adaptive immune cell components. The summarized results in this review suggest that IL-33 exerts dual-functioning, pro- as well as anti-tumorigenic effects depending on the tumor type, expression levels, cellular context, and cytokine milieu. A better understanding of the distinct roles of IL-33 in epithelial, stromal, and immune cell compartments will benefit the development of a targeting strategy for this IL-33/ST2 axis for cancer immunotherapy.

Interleukin-35 Suppresses Interleukin-9-Secreting CD4+ T Cell Activity in Patients With Hepatitis B-Related Hepatocellular Carcinoma

Chronic hepatitis B virus (HBV) infection induces dysfunction of immune response and chronic liver damage. However, the mechanisms that account for HBV-related hepatocellular carcinoma (HCC) are poorly understood. The aim of present study was to investigate the modulatory role of interleukin (IL)-35, an immunosuppressive cytokine, to IL-9-secreting T cells in hepatitis B-related HCC. Twenty-two HBV-related HCC patients, twenty-seven chronic hepatitis B (CHB) patients, and eleven controls were enrolled. Serum IL-35 and IL-9 concentration was measured by ELISA. Peripheral and liver-infiltrating non-specific and HBV-specific Th9 and Tc9 cells were assessed by flow cytometry. The regulatory activity of IL-35 to peripheral and liver-infiltrating Th9 cells was assessed in co-culture system between CD8⁺ T cells and HepG2.2.15 cells. Serum IL-35 was up-regulated, while IL-9 was down-regulated in HBV-related HCC patients compared with in CHB patients and controls. Peripheral non-specific and HBV-specific Th9 cells, but not Tc9 cells, were decreased in HBV-related HCC patients. Liver-infiltrating non-specific and HBV-specific Th9 cells were also reduced in HCC tumor sites. CD8⁺ T cells from CHB and HBV-related HCC patients revealed decreased cytotoxicity compared with those from controls. Autologous Th9 cells mediated the elevation of CD8⁺ T cell cytotoxicity, and this process was depending on IL-9 secretion. Recombinant IL-35 stimulation inhibited IL-9 secretion and PU.1 mRNA expression in non-specific and HBV-specific Th9 cells, leading to the suppression of Th9-mediated CD8⁺ T cell cytotoxicity in CHB and HBV-related HCC patients. Our current data indicated that IL-35 might dampen non-specific and HBV-specific Th9 cells activity in HBV-related HCC patients.

Atrazine-induced cell-mediated immunotoxicity in rabbits and the ameliorating role of glycyrrhizic acid

The present study aimed to explain the mechanisms involved in cell-mediated immunotoxicity of atrazine (ATR) in rabbits and to evaluate the ameliorative role of glycyrrhizic acid (GA) against such toxic effects. Forty rabbits were assigned into 4 equal groups: control, ATR, GA, and ATR + GA groups. ATR (2475 ppm) and GA (60 μg of GA/ml of water) were administrated via food and drinking water, respectively, for 60 consecutive days. The cell-mediated immunotoxicity of ATR was clarified by the induced thymus immunotoxicity through downregulation of interleukin (IL)-9 gene and interferon-γ (IFN-γ) gene expression, upregulation in caspase-3, and significant decrease in the total leukocytic and lymphocyte counts. Histopathological investigations demonstrated severe depletion of lymphoid follicles in the medulla of the thymus gland. On the other hand, co-administration of GA for group 4 improved most of the undesirable impacts of ATR. In conclusion, the alteration in IL-9/IFN-γ expression may involve ATR-induced thymocyte apoptosis which may explain the mechanisms of ATR-induced cell-mediated immunotoxicity with a possible amelioration influence of GA administration.

Th9 and Th17 cells: the controversial twins in cancer immunity

Th17 cells (producing IL-17) and Th9 cells (producing IL-9) exhibit functional plasticity, and their role in tumorigenicity is controversial. Th17/IL-17 and Th9/IL-9 exhibit critical, but often opposing, roles in tumor progression. In this issue of the JCI, Salazar et al. show that while IL-17 and IL-9 induced distinct but complementary molecular pathways, both cytokines also induced epithelial-mesenchymal transition (EMT) in lung cancer cells and promoted metastatic spreading. A key question before us now is whether IL-9 and IL-17 contribute to tumor progression in a sequential and stage-specific manner within the tumor microenvironment.

Antibody-based delivery of interleukin-9 to neovascular structures: Therapeutic evaluation in cancer and arthritis

Interleukin-9 is a cytokine with multiple functions, including the ability to activate group 2 innate lymphoid cells, which has been postulated to be therapeutically active in mouse models of arthritis. Similarly, interleukin-9 has been suggested to play an important role in tumor immunity. Here, we describe the cloning, expression, and characterization of three fusion proteins based on murine interleukin-9 and the F8 antibody, specific to the alternatively spliced EDA domain of fibronectin. EDA is strongly expressed in cancer and in various arthritic conditions, while being undetectable in the majority of healthy organs. Interleukin-9-based fusion proteins with an irrelevant antibody specific to hen egg lysozyme served as negative control in our study. The fusion proteins were characterized by quantitative biodistribution analysis in tumor-bearing mice using radioiodinated protein preparations. The highest tumor uptake and best tumor:organ ratios were observed for a format, in which the interleukin-9 moiety was flanked by two units of the F8 antibody in single-chain Fv format. Biological activity of interleukin-9 was retained when the payload was fused to antibodies. However, the targeted delivery of interleukin-9 to the disease site resulted in a modest anti-tumor activity in three different murine models of cancer (K1735M2, CT26, and F9), while no therapeutic benefit was observed in a collagen induced model of arthritis. Collectively, these results confirm the possibility to deliver interleukin-9 to the site of disease but cast doubts about the alleged therapeutic activity of this cytokine in cancer and arthritis, which has been postulated in previous publications.

ILC2-derived IL-9 inhibits colorectal cancer progression by activating CD8+ T cells

Group 2 innate lymphoid cells (ILC2s), characterized by secretion of type 2 cytokines, regulate multiple immune responses. ILC2s are found in different tumor tissues, and ILC2-derived interleukin (IL)-4, IL-5, and IL-13 act on the cells in tumor microenvironment to participate in tumor progression. ILC2s are abundant in colorectal cancer (CRC) tissue, but the role of ILC2s in CRC remains unclear. In this study, we found that the percentage of ILC2s was higher in CRC tissue than in the adjacent normal tissue and that these ILC2s were the dominant IL-9-secreting cell-subsets in CRC tissue, as shown by flow cytometry analysis. ILC2s-derived IL-9 could activate CD8⁺ T cells to inhibit tumor growth, while anti-IL-9 reversed this effect. In vivo experiments showed that neutralizing ILC2s promoted tumor growth, while tumor inhibition occurred by intravenous injection of IL-9. In conclusion, our results demonstrated that ILC2-derived IL-9 could activate CD8⁺ T cells to promote anti-tumor effects in CRC.

Anti-Tumorigenic Activities of IL-33: A Mechanistic Insight

Interleukin-33 (IL-33) is an epithelial-derived cytokine that can be released upon tissue damage, stress, or infection, acting as an alarmin for the immune system. IL-33 has long been studied in the context of Th2-related immunopathologies, such as allergic diseases and parasitic infections. However, its capacity to stimulate also Th1-type of immune responses is now well established. IL-33 binds to its specific receptor ST2 expressed by most immune cell populations, modulating a variety of responses. In cancer immunity, IL-33 can display both pro-tumoral and anti-tumoral functions, depending on the specific microenvironment. Recent findings indicate that IL-33 can effectively stimulate immune effector cells (NK and CD8⁺ T cells), eosinophils, basophils and type 2 innate lymphoid cells (ILC2) promoting direct and indirect anti-tumoral activities. In this review, we summarize the most recent advances on anti-tumor immune mechanisms operated by IL-33, including the modulation of immune checkpoint molecules, with the aim to understand its potential as a therapeutic target in cancer.

Crosstalk between the Producers and Immune Targets of IL-9

IL-9 has been reported to play dual roles in the pathogenesis of autoimmune disorders and cancers. The collaboration of IL-9 with microenvironmental factors including the broader cytokine milieu and other cellular components may provide important keys to explain its conflicting effects in chronic conditions. In this review, we summarize recent findings on the cellular sources of, and immunological responders to IL-9, in order to interpret the role of IL-9 in the regulation of immune responses. This knowledge will provide new perspectives to improve clinical benefits and limit adverse effects of IL-9 when treating pathologic conditions.

Interleukin-9-secreting CD4+ T cells regulate CD8+ T cells cytotoxicity in patients with acute coronary syndromes

T cells play vital roles in the development and progression of acute coronary syndromes (ACS), including cytotoxicity mediated by CD8⁺ T cells and immunoregulatory activity mediated by CD4⁺ T cells. Interleukin (IL)-9-secreting CD4⁺ T cells (Th9 cells) were recently found to be involved in the onset of ACS. We investigated regulatory role of Th9 cells to CD8⁺ T cells in patients with stable angina pectoris, unstable angina pectoris, and acute myocardial infarction (AMI). Circulating Th9 cells percentage, plasma IL-9 level, and PU.1 mRNA relative level was up-regulated in AMI patients compared with controls. There was no significant difference of IL-9-secreting CD8⁺ T cells percentage among groups. CD8⁺ T cells from AMI patients revealed increased cytotoxicity than those from controls, which presented as enhanced cytotolytic activity to target cells, increased interferon-γ and tumor necrosis factor-α secretion, elevated perforin and granzyme B production, and reduced programmed death-1 and cytotoxic T lymphocyte-associated protein 4. IL-9 stimulation did not affect proliferation, but promoted CD8⁺ T-cell cytotoxicity from both controls and AMI patients. IL-9-secreting CD4⁺ T cells were enriched in CD4⁺ CCR4^- CCR6^- CXCR3^- cells. The enhancement of CD8⁺ T-cell cytotoxicity induced by CD4⁺ CCR4^- CCR6^- CXCR3^- cells was dependent on IL-9 secretion. The present results indicated that up-regulation of IL-9-secreting CD4⁺ T cells may contribute to pathogenesis of AMI through enhancement of CD8⁺ T-cell cytotoxicity.

STAT3: A key signaling molecule for converting cold to hot tumors

Tumors can be classified as cold or hot according to the degree of immune cell infiltration into tumor tissues; cold tumors are insensitive to either chemotherapy or immunotherapy and are associated with poor prognosis. Recent studies have shown that STAT3 signaling molecules hinder the conversion of cold to hot tumors by regulating immunosuppressive molecule secretion and immunosuppressive cell functions. This review aims to present the most recent studies on how STAT3 regulates cold tumor formation and discuss its research status in cancer therapy. We also present insight for designing new therapeutic strategies to "heat" tumors and provide a reference for tumor immunotherapy.