The role of the IL-22/IL-22R1 axis in cancer

Recent advances in mRNA-based cancer vaccines encoding immunostimulants and their delivery strategies

The high prevalence of drug resistance, relapse, and unfavorable response rate of conventional cancer therapies necessitate the development of more efficient treatment modalities. Immunotherapy represents a novel therapeutic approach to cancer treatment in which the immune system's potential is harnessed to recognize and eliminate tumor cells. mRNA cancer vaccines, as a burgeoning field of immunotherapy, have recently drawn particular attention, and among mRNAs encoding tumor-associated antigens, tumor-specific antigens, and immune stimulatory factors, the latter has been relatively less explored. These immunostimulatory mRNAs encode a range of proteins, including stimulatory ligands, receptors, enzymes, pro-inflammatory cytokines, and inhibitory binding proteins, which collectively augment the host immune system's ability against cancerous cells. In this review, we aimed to provide a comprehensive account of mRNA-based cancer vaccines encoding immune stimulants, encompassing their current status, mechanisms of action, delivery strategies employed, as well as recent advances in preclinical and clinical studies. The potential challenges, strategies and future perspectives have also been discussed.

The role of IL-22 in cancer

Interleukin-22, discovered in the year of 2000, is a pleiotropic Th17 cytokine from the IL-10 family of cytokines. IL-22 signals through the type 2 cytokine receptor complex IL-22R and predominantly activates STAT3. This pathway leads to the transcription of several different types of genes, giving IL-22 context-specific functions ranging from inducing antimicrobial peptide expression to target cell proliferation. In recent years, it has been shown that IL-22 is involved in the pathogenesis of neoplasia in some cancers through its pro-proliferative and anti-apoptotic effects. This review highlights studies with recent discoveries and conclusions drawn on IL-22 and its involvement and function in various cancers. Such a study may be helpful to better understand the role of IL-22 in cancer so that new treatment could be developed targeting IL-22.

IL-22 in Atopic Dermatitis

Atopic dermatitis (AD) is a prevalent and chronic inflammatory skin condition characterized by a multifaceted pathophysiology that gives rise to diverse clinical manifestations. The management of AD remains challenging due to the suboptimal efficacy of existing treatment options. Nonetheless, recent progress in elucidating the underlying mechanisms of the disease has facilitated the identification of new potential therapeutic targets and promising drug candidates. In this review, we summarize the newest data, considering multiple connections between IL-22 and AD. The presence of circulating IL-22 has been found to correlate with the severity of AD and is identified as a critical factor driving the inflammatory response associated with the condition. Elevated levels of IL-22 in patients with AD are correlated with increased proliferation of keratinocytes, alterations in the skin microbiota, and impaired epidermal barrier function. Collectively, these factors contribute to the manifestation of the characteristic symptoms observed in AD.

A comprehensive immunobiology review of IBD: With a specific glance to Th22 lymphocytes development, biology, function, and role in IBD

The two primary forms of inflammatory disorders of the small intestine andcolon that make up inflammatory bowel disease (IBD) are ulcerative colitis (UC) and Crohn's disease (CD). While ulcerative colitis primarily affects the colon and the rectum, CD affects the small and large intestines, as well as the esophagus,mouth, anus, andstomach. Although the etiology of IBD is not completely clear, and there are many unknowns about it, the development, progression, and recurrence of IBD are significantly influenced by the activity of immune system cells, particularly lymphocytes, given that the disease is primarily caused by the immune system stimulation and activation against gastrointestinal (GI) tract components due to the inflammation caused by environmental factors such as viral or bacterial infections, etc. in genetically predisposed individuals. Maintaining homeostasis and the integrity of the mucosal barrier are critical in stopping the development of IBD. Specific immune system cells and the quantity of secretory mucus and microbiome are vital in maintaining this stability. Th22 cells are helper T lymphocyte subtypes that are particularly important for maintaining the integrity and equilibrium of the mucosal barrier. This review discusses the most recent research on these cells' biology, function, and evolution and their involvement in IBD.

Efficient Colon Cancer Immunogene Therapy Through Co-Delivery of IL-22BP mRNA and Tumor Cell Lysate by CLSV Nanoparticles

Background

Messenger ribonucleic acid (mRNA)-based gene therapy has great potential in cancer treatment. However, the application of mRNA-based cancer treatment could be further developed. Elevated delivery ability and enhanced immune response are advantages for expanding the application of mRNA-based cancer therapy. It is crucial that the prepared carrier can cause an immune reaction based on the efficient delivery of mRNA.

Methods

We reported DMP nanoparticle previously, which was obtained by the self-assembly of 1,2-dioleoyl-3-trimethylammonium propane (DOTAP) and (ethylene glycol)-b-poly (ε-caprolactone) (mPEG-PCL). Research demonstrated that DMP can deliver mRNA, siRNA, and plasmid. And it is applied to various tumor types. In our work, the tumor cell lysate was introduced to the internal DMP chain, fusing cell-penetrating peptides (CPPs) modification on the surface forming the CLSV system. And then mixed encoded IL-22BP (interleukin-22 binding protein) mRNA and CLSV to form CLSV/IL-22BP complex.

Results

The size of the CLSV system was 213.2 nm, and the potential was 45.7 mV. The transfection efficiency of the CLSV system is up to 76.45% in C26 cells via the micropinocytosis pathway. The CLSV system also could induce an immune response and significantly elevate the expression of CD80, CD86, and MHC-II in vivo. Then, by binding with IL-22BP (Interleukin-22 binding protein) mRNA, the CLSV/IL-22BP complex inhibited tumor cell growth, with an inhibition rate of up to 82.3% in vitro. The CLSV/IL-22BP complex also inhibited tumor growth in vivo, the tumor cell growth inhibition up to 75.0% in the subcutaneous tumor model, and 84.9% in the abdominal cavity metastasis tumor model.

Conclusion

Our work demonstrates that the CLSV system represents a potent potential for mRNA delivery.

Gut microbiota-mediated IL-22 alleviates metabolic inflammation

Low-grade chronic inflammation, also known as metabolic inflammation, promotes the development of metabolic diseases. Increasing evidence suggests that changes in gut microbes and metabolites disrupt the integrity of the gut barrier and exert significant effects on the metabolism of various tissues, including the liver and adipose tissue, thereby contributing to metabolic inflammation. We observed that IL-22 is a key signaling molecule that serves as a bridge between intestinal microbes and the host, effectively alleviating metabolic inflammation by modulating the host immunomodulatory network. Here, we focused on elucidating the underlying mechanisms by which the gut microbiota and their metabolites reduce inflammation via IL-22, highlighting the favorable impact of IL-22 on metabolic inflammation. Furthermore, we discuss the potential of IL-22 as a therapeutic target for the management of metabolic inflammation and related diseases.

CD4+ T cell-derived IL-22 enhances liver metastasis by promoting angiogenesis

Metastasis is a cancer-related systemic disease and is responsible for the greatest mortality rate among cancer patients. Interestingly, the interaction between the immune system and cancer cells seems to play a key role in metastasis formation in the target organ. However, this complex network is only partially understood. We previously found that IL-22 produced by tissue resident iNKT17 cells promotes cancer cell extravasation, the early step of metastasis. Based on these data, we aimed here to decipher the role of IL-22 in the last step of metastasis formation. We found that IL-22 levels were increased in established metastatic sites in both human and mouse. We also found that Th22 cells were the key source of IL-22 in established metastasis sites, and that deletion of IL-22 in CD4+ T cells was protective in liver metastasis formation. Accordingly, the administration of a murine IL-22 neutralizing antibody in the establishment of metastasis formation significantly reduced the metastatic burden in a mouse model. Mechanistically, IL-22-producing Th22 cells promoted angiogenesis in established metastasis sites. In conclusion, our findings highlight that IL-22 is equally as important in contributing to metastasis formation at late metastatic stages, and thus, identify it as a novel therapeutic target in established metastasis.

Role of cytokine in malignant T-cell metabolism and subsequent alternation in T-cell tumor microenvironment

T cells are an important component of adaptive immunity and T-cell-derived lymphomas are very complex due to many functional sub-types and functional elasticity of T-cells. As with other tumors, tissues specific factors are crucial in the development of T-cell lymphomas. In addition to neoplastic cells, T- cell lymphomas consist of a tumor micro-environment composed of normal cells and stroma. Numerous studies established the qualitative and quantitative differences between the tumor microenvironment and normal cell surroundings. Interaction between the various component of the tumor microenvironment is crucial since tumor cells can change the microenvironment and vice versa. In normal T-cell development, T-cells must respond to various stimulants deferentially and during these courses of adaptation. T-cells undergo various metabolic alterations. From the stage of quiescence to attention of fully active form T-cells undergoes various stage in terms of metabolic activity. Predominantly quiescent T-cells have ATP-generating metabolism while during the proliferative stage, their metabolism tilted towards the growth-promoting pathways. In addition to this, a functionally different subset of T-cells requires to activate the different metabolic pathways, and consequently, this regulation of the metabolic pathway control activation and function of T-cells. So, it is obvious that dynamic, and well-regulated metabolic pathways are important for the normal functioning of T-cells and their interaction with the microenvironment. There are various cell signaling mechanisms of metabolism are involved in this regulation and more and more studies have suggested the involvement of additional signaling in the development of the overall metabolic phenotype of T cells. These important signaling mediators include cytokines and hormones. The impact and role of these mediators especially the cytokines on the interplay between T-cell metabolism and the interaction of T-cells with their micro-environments in the context of T-cells lymphomas are discussed in this review article.

Germline mechanisms of immunotherapy toxicities in the era of genome-wide association studies

Cancer immunotherapy has revolutionized the treatment of advanced cancers and is quickly becoming an option for early-stage disease. By reactivating the host immune system, immunotherapy harnesses patients' innate defenses to eradicate the tumor. By putatively similar mechanisms, immunotherapy can also substantially increase the risk of toxicities or immune-related adverse events (irAEs). Severe irAEs can lead to hospitalization, treatment discontinuation, lifelong immune complications, or even death. Many irAEs present with similar symptoms to heritable autoimmune diseases, suggesting that germline genetics may contribute to their onset. Recently, genome-wide association studies (GWAS) of irAEs have identified common germline associations and putative mechanisms, lending support to this hypothesis. A wide range of well-established GWAS methods can potentially be harnessed to understand the etiology of irAEs specifically and immunotherapy outcomes broadly. This review summarizes current findings regarding germline effects on immunotherapy outcomes and discusses opportunities and challenges for leveraging germline genetics to understand, predict, and treat irAEs.

Interleukin-22 promotes the proliferation and migration of hepatocellular carcinoma cells via the phosphoinositide 3-kinase (PI3K/AKT) signaling pathway

BACKGROUND

Interleukin-22 (IL-22) is a pro-inflammatory cytokine released during the immune response in chronic liver injury. Although IL-22 mediates tissue regeneration, its uncontrolled production may generate a carcinogenic environment resulting in hepatocellular carcinoma (HCC). This study aims to identify the effect of IL-22 on anti-apoptotic and metastatic genes and the molecular pathways responsible for IL-22-mediated hepatic carcinogenesis.

METHODS AND RESULTS

Three cancerous liver lines, HepG2, SNU-387, Huh7, and one normal liver line, THLE2, were treated with IL-22. RT-qPCR analysis was conducted to study the role of IL-22 in altering the expression levels of anti-apoptotic genes, MCL-1 and BCL-2, and metastatic genes, MMP-7 and MMP-9. A significant increase in expression levels of these genes was observed after IL-22 treatment. Furthermore, to explore the major pathways involved in IL-22-mediated upregulation of anti-apoptotic and metastatic genes, cells were treated with inhibitors of JAK/STAT and PI3K/AKT pathways along with IL-22. Resultantly, a significant decrease in expression levels of target genes was observed, indicating the involvement of JAK/STAT and PI3K/AKT signaling cascades in IL-22-mediated oncogenesis. Finally, Cell Scratch assay was performed to check the effect of IL-22 and inhibitors of JAK/STAT and PI3K/AKT on the metastatic potential of liver cells. While migration was observed in Huh7 and THLE2 cells treated with IL-22, no migration was observed in cells treated with IL-22 along with JAK/STAT and PI3K/AKT inhibitors. Results indicate that IL-22 encourages metastasis in HCC cells via the JAK/STAT and PI3K/AKT pathways.

CONCLUSION

Results showed that IL-22 upregulates anti-apoptotic and metastatic genes in HCC through JAK/STAT and PI3K/AKT signaling pathways.

Mechanisms of obesity- and diabetes mellitus-related pancreatic carcinogenesis: a comprehensive and systematic review

Research on obesity- and diabetes mellitus (DM)-related carcinogenesis has expanded exponentially since these two diseases were recognized as important risk factors for cancers. The growing interest in this area is prominently actuated by the increasing obesity and DM prevalence, which is partially responsible for the slight but constant increase in pancreatic cancer (PC) occurrence. PC is a highly lethal malignancy characterized by its insidious symptoms, delayed diagnosis, and devastating prognosis. The intricate process of obesity and DM promoting pancreatic carcinogenesis involves their local impact on the pancreas and concurrent whole-body systemic changes that are suitable for cancer initiation. The main mechanisms involved in this process include the excessive accumulation of various nutrients and metabolites promoting carcinogenesis directly while also aggravating mutagenic and carcinogenic metabolic disorders by affecting multiple pathways. Detrimental alterations in gastrointestinal and sex hormone levels and microbiome dysfunction further compromise immunometabolic regulation and contribute to the establishment of an immunosuppressive tumor microenvironment (TME) for carcinogenesis, which can be exacerbated by several crucial pathophysiological processes and TME components, such as autophagy, endoplasmic reticulum stress, oxidative stress, epithelial-mesenchymal transition, and exosome secretion. This review provides a comprehensive and critical analysis of the immunometabolic mechanisms of obesity- and DM-related pancreatic carcinogenesis and dissects how metabolic disorders impair anticancer immunity and influence pathophysiological processes to favor cancer initiation.

Role and Potential of Different T Helper Cell Subsets in Adoptive Cell Therapy

Historically, CD8⁺ T cells have been considered the most relevant effector cells involved in the immune response against tumors and have therefore been the focus of most cancer immunotherapy approaches. However, CD4⁺ T cells and their secreted factors also play a crucial role in the tumor microenvironment and can orchestrate both pro- and antitumoral immune responses. Depending on the cytokine milieu to which they are exposed, CD4⁺ T cells can differentiate into several phenotypically different subsets with very divergent effects on tumor progression. In this review, we provide an overview of the current knowledge about the role of the different T helper subsets in the immune system, with special emphasis on their implication in antitumoral immune responses. Furthermore, we also summarize therapeutic applications of each subset and its associated cytokines in the adoptive cell therapy of cancer.

T cell-derived interleukin-22 drives the expression of CD155 by cancer cells to suppress NK cell function and promote metastasis

Although T cells can exert potent anti-tumor immunity, a subset of T helper (Th) cells producing interleukin-22 (IL-22) in breast and lung tumors is linked to dismal patient outcome. Here, we examined the mechanisms whereby these T cells contribute to disease. In murine models of lung and breast cancer, constitutional and T cell-specific deletion of Il22 reduced metastases without affecting primary tumor growth. Deletion of the IL-22 receptor on cancer cells decreases metastasis to a degree similar to that seen in IL-22-deficient mice. IL-22 induced high expression of CD155, which bound to the activating receptor CD226 on NK cells. Excessive activation led to decreased amounts of CD226 and functionally impaired NK cells, which elevated the metastatic burden. IL-22 signaling was also associated with CD155 expression in human datasets and with poor patient outcomes. Taken together, our findings reveal an immunosuppressive circuit activated by T cell-derived IL-22 that promotes lung metastasis.

T lymphocyte cell: A pivotal player in lung cancer

Lung cancer is responsible for the leading cause of cancer-related death worldwide, which lacks effective therapies. In recent years, accumulating evidence on the understanding of the antitumor activity of the immune system has demonstrated that immunotherapy is one of the powerful alternatives in lung cancer therapy. T cells are the core of cellular immunotherapy, which are critical for tumorigenesis and the treatment of lung cancer. Based on the different expressions of surface molecules and functional points, T cells can be subdivided into regulatory T cells, T helper cells, cytotoxic T lymphocytes, and other unconventional T cells, including γδ T cells, nature killer T cells and mucosal-associated invariant T cells. Advances in our understanding of T cells' functional mechanism will lead to a number of clinical trials on the discovery and development of new treatment strategies. Thus, we summarize the biological functions and regulations of T cells on tumorigenesis, progression, metastasis, and prognosis in lung cancer. Furthermore, we discuss the current advancements of technologies and potentials of T-cell-oriented therapeutic targets for lung cancer.

Cancer-associated fibroblasts in nonsmall cell lung cancer: From molecular mechanisms to clinical implications

Lung cancer is the common and leading cause of cancer death worldwide. The tumor microenvironment has been recognized to be instrumental in tumorigenesis. To have a deep understanding of the molecular mechanism of nonsmall cell lung carcinoma (NSCLC), cancer-associated fibroblasts (CAFs) have gained increasing research interests. CAFs belong to the crucial and dominant cell population in the tumor microenvironment to support the cancer cells. The interplay and partnership between cancer cells and CAFs contribute to each stage of tumorigenesis. CAFs exhibit prominent heterogeneity and secrete different kinds of cytokines and chemokines, growth factors and extracellular matrix proteins involved in cancer cell proliferation, invasion, metastasis and chemoresistance. Many studies focused on the protumorigenic functions of CAFs, yet many challenges about the heterogeneity of CAFS remain unresolved. This review comprehensively summarized the tumor-promoting role and molecular mechanisms of CAFs in NSCLC, including their origin, phenotypic changes and heterogeneity and their functional roles in carcinogenesis. Meanwhile, we also highlighted the updated molecular classifications based on the molecular features and functional roles of CAFs. With the development of cutting-edge platforms and further investigations of CAFs, novel therapeutic strategies for accurately targeting CAFs in NSCLC may be developed based on the increased understanding of the relevant molecular mechanisms.

Th17, Th22, and Myeloid-Derived Suppressor Cell Population Dynamics and Response to IL-6 in 4T1 Mammary Carcinoma

Immunotherapies relying on type 1 immunity have shown robust clinical responses in some cancers yet remain relatively ineffective in solid breast tumors. Polarization toward type 2 immunity and expansion of myeloid-derived suppressor cells (MDSC) confer resistance to therapy, though it remains unclear whether polarization toward type 3 immunity occurs or has a similar effect. Therefore, we investigated the involvement of type 3 T_h17 and T_h22 cells and their association with expanding MDSC populations in the 4T1 mouse mammary carcinoma model. T_h17 and T_h22 were detected in the earliest measurable mass at d 14 and remained present until the final sampling on d 28. In peripheral organs, T_h17 populations were significantly higher than the non-tumor bearing control and peaked early at d 7, before a palpable tumor had formed. Peripheral T_h22 proportions were also significantly increased, though at later times when tumors were established. To further address the mechanism underlying type 3 immune cell and MDSC recruitment, we used CRISPR-Cas9 to knock out 4T1 tumor production of interleukin-6 (4T1-IL-6-KO), which functions in myelopoiesis, MDSC recruitment, and T_h maturation. While 4T1-IL-6-KO tumor growth was similar to the control, the reduced IL-6 significantly expanded the total CD4⁺ T_h population and T_h17 in tumors, while T_h22 and MDSC were reduced in all tissues; this suggests that clinical IL-6 depletion combined with immunotherapy could improve outcomes. In sum, 4T1 mammary carcinomas secrete IL-6 and other factors, to polarize and reshape T_h populations and expand distinct T_h17 and T_h22 populations, which may facilitate tumor growth and confer immunotherapy resistance.

scRNA-seq of gastric tumor shows complex intercellular interaction with an alternative T cell exhaustion trajectory

The tumor microenvironment (TME) in gastric cancer (GC) has been shown to be important for tumor control but the specific characteristics for GC are not fully appreciated. We generated an atlas of 166,533 cells from 10 GC patients with matched paratumor tissues and blood. Our results show tumor-associated stromal cells (TASCs) have upregulated activity of Wnt signaling and angiogenesis, and are negatively correlated with survival. Tumor-associated macrophages and LAMP3⁺ DCs are involved in mediating T cell activity and form intercellular interaction hubs with TASCs. Clonotype and trajectory analysis demonstrates that Tc17 (IL-17⁺CD8⁺ T cells) originate from tissue-resident memory T cells and can subsequently differentiate into exhausted T cells, suggesting an alternative pathway for T cell exhaustion. Our results indicate that IL17⁺ cells may promote tumor progression through IL17, IL22, and IL26 signaling, highlighting the possibility of targeting IL17⁺ cells and associated signaling pathways as a therapeutic strategy to treat GC.

Gastric cancer can vary in tumour stage and immune cell involvement. Here the authors compare gene expression in immune cell types from the blood and the tumour site from GC patients using single cell and TCR sequencing and show that IL17⁺CD8⁺ T cells have a phenotype related to that seen with exhausted cells.

IL22RA1/JAK/STAT Signaling Acts As a Cancer Target Through Pan-Cancer Analysis

Cytokines and cytokine receptors are important mediators in immunity and cancer development. Interleukin 22 (IL22) is one of the most important cytokines which has protumor effect. Given that common and specific roles of cytokines/receptors in multiple cancers, we conducted a pan-cancer study to investigate the role of IL22RA1 in cancer using The Cancer Genome Atlas (TCGA) database. Notably, we found IL22RA1 transcript was upregulated in 11 cancer types compared with their corresponding control. The mRNA expression level of IL22RA1 was highest in the pancreas among tumor tissues. The higher expression of IL22RA1 was associated with worse overall survival rate in patients. A total of 30 IL22RA1-correlated genes (e.g. IL17D, IL22RA2, IL20RB, IL10RA, IL10RB, TSLP and TYK2) are involved in the JAK/STAT pathway which promotes tumor progression. The upregulation of IL22RA1 in tumors was correlated with immune cell infiltration level. Higher expression of IL22RA2, IL20RB, IL10RA, IL10RB, TSLP, TYK2, STAT1 and STAT3 was associated with decreased overall survival rate in patients. IL22RA1 mutation was observed more in uterine cancer and melanoma compared with the other cancer types. Deactivation of IL22RA1 induced a lot of changes in gene expression. IL22RA1 mutants had upregulated DNA damage/repair genes in uterine cancer, whereas downregulated genes in the FoxO signaling pathway. In melanoma, mutation of IL22RA1 can upregulate the HIF signaling pathway but downregulate metabolic pathways. Our study suggests that IL22RA1/JAK/STAT signaling can be an important target for cancer treatment.

Identification of a Prognostic Signature Composed of GPI, IL22RA1, CCT6A and SPOCK1 for Lung Adenocarcinoma Based on Bioinformatic Analysis of lncRNA-Mediated ceRNA Network and Sample Validation

Lung adenocarcinoma (LUAD) is one of the most common malignant tumors with high morbidity and mortality in China and worldwide. Long non-coding RNAs (lncRNAs) as the competing endogenous RNA (ceRNA) play an essential role in the occurrence and development of LUAD. However, identifying lncRNA-related biomarkers to improve the accuracy of LUAD prognosis remains to be determined. This study downloaded RNA sequence data from The Cancer Genome Atlas (TCGA) database and identified the differential RNAs by bioinformatics. A total of 214 lncRNA, 198 miRNA and 2989 mRNA were differentially identified between LUAD and adjacent nontumor samples. According to the ceRNA hypothesis, we constructed a lncRNA-miRNA-mRNA network including 95 protein-coding mRNAs, 7 lncRNAs and 15 miRNAs, and found 24 node genes in this network were significantly associated with the overall survival of LUAD patients. Subsequently, through LASSO regression and multivariate Cox regression analyses, a four-gene prognostic signature composed of GPI, IL22RA1, CCT6A and SPOCK1 was developed based on the node genes of the lncRNA-mediated ceRNA network, demonstrating high performance in predicting the survival and chemotherapeutic responses of low- and high-risk LUAD patients. Finally, independent prognostic factors were further analyzed and combined into a well-executed nomogram that showed strong potential for clinical applications. In summary, the data from the current study suggested that the four-gene signature obtained from analysis of lncRNA-mediated ceRNA could serve as a reliable biomarker for LUAD prognosis and evaluation of chemotherapeutic response.

Distinct Expression Patterns of Interleukin-22 Receptor 1 on Blood Hematopoietic Cells in SARS-CoV-2 Infection

The new pandemic virus SARS-CoV-2 is characterized by uncontrolled hyper-inflammation in severe cases. As the IL-22/IL-22R1 axis was reported to be involved in inflammation during viral infections, we characterized the expression of IL-22 receptor1, IL-22 and IL-22 binding protein in COVID-19 patients. Blood samples were collected from 19 non-severe and 14 severe patients on the day they presented (D0), at D14, and six months later, and from 6 non-infected controls. The IL-22R1 expression was characterized by flow cytometry. Results were related to HLA-DR expression of myeloid cells, to plasma concentrations of different cytokines and chemokines and NK cells and T lymphocytes functions characterized by their IFN-γ, IL-22, IL-17A, granzyme B and perforin content. The numbers of IL-22R1⁺ classical, intermediate, and non-classical monocytes and the proportions of IL-22R1⁺ plasmacytoid DC (pDC), myeloid DC1 and DC2 (mDC1, mDC2) were higher in patients than controls at D0. The proportions of IL-22R1⁺ classical and intermediate monocytes, and pDC and mDC2 remained high for six months. High proportions of IL-22R1⁺ non-classical monocytes and mDC2 displayed HLA-DR^high expression and were thus activated. Multivariate analysis for all IL-22R1⁺ myeloid cells discriminated the severity of the disease (AUC=0.9023). However, correlation analysis between IL-22R1⁺ cell subsets and plasma chemokine concentrations suggested pro-inflammatory effects of some subsets and protective effects of others. The numbers of IL-22R1⁺ classical monocytes and pDC were positively correlated with pro-inflammatory chemokines MCP-1 and IP-10 in severe infections, whereas IL-22R1⁺ intermediate monocytes were negatively correlated with IL-6, IFN-α and CRP in non-severe infections. Moreover, in the absence of in vitro stimulation, NK and CD4⁺ T cells produced IFN-γ and IL-22, and CD4⁺ and CD8⁺ T cells produced IL-17A. CD4⁺ T lymphocytes also expressed IL-22R1, the density of its expression defining two different functional subsets. In conclusion, we provide the first evidence that SARS-CoV-2 infection is characterized by an abnormal expression of IL22R1 on blood myeloid cells and CD4⁺ T lymphocytes. Our results suggest that the involvement of the IL-22R1/IL-22 axis could be protective at the beginning of SARS-CoV-2 infection but could shift to a detrimental response over time.

Aryl Hydrocarbon Receptor Signaling Synergizes with TLR/NF-κB-Signaling for Induction of IL-22 Through Canonical and Non-Canonical AhR Pathways

Interleukin 22 (IL-22) is critically involved in gut immunity and host defense and primarily produced by activated T cells. In different circumstances IL-22 may contribute to pathological conditions or act as a cancer promoting cytokine secreted by infiltrating immune cells. Here we show that bone marrow-derived macrophages (BMM) express and produce IL-22 after activation of the aryl hydrocarbon receptor (AhR) when cells are activated through the Toll-like receptor (TLR) family. The additional activation of AhR triggered a significant induction of IL-22 in TLR-activated BMM. Deletion and mutation constructs of the IL-22 promoter revealed that a consensus DRE and RelBAhRE binding element are necessary to mediate the synergistic effects of AhR and TLR ligands. Inhibitor studies and analysis of BMM derived from knockout mice confirmed that the synergistic induction of IL-22 by AhR and TLR ligands depend on the expression of AhR and Nuclear Factor-kappa B (NF-κB) member RelB. The exposure to particulate matter (PM) collected from traffic related air pollution (TRAP) and wildfires activated AhR as well as NF-κB signaling and significantly induced the expression of IL-22. In summary this study shows that simultaneous activation of the AhR and NF-κB signaling pathways leads to synergistic and prolonged induction of IL-22 by integrating signals of the canonical and non-canonical AhR pathway.

IFNγ-IL-17-IL-22+CD4+ subset and IL-22-producing cells in tumor draining lymph nodes of patients with breast cancer

BACKGROUND

A recently introduced CD4+ T subset that mainly secretes interleukin (IL-) 22 has been reported to be associated with a variety of tumors, including colon, gastric, hepatocellular, and small- and large-cell lung carcinoma. Both tumor-promoting and - suppressing roles have been suggested for these cells. In the present study, we aimed to investigate the frequency of IL-22-producing subsets in tumor-draining lymph nodes (TDLNs) of the patients with breast cancer and determine their association with the clinicopathological characterizations of the disease.

METHODS

Thirty untreated women diagnosed with breast cancer were enrolled and their axillary lymph nodes were dissected during surgery. Mononuclear cells were isolated using Ficoll density gradient, activated, permeabilized, and stained by fluorochrome-conjugated antibodies against CD4, IL-22, IL-17, and IFNγ. The cells were then acquired on the FACSCalibur flow cytometer, and raw data was analyzed by the FlowJo software package (V10).

RESULTS

Our results demonstrated that 2.39% ± 0.39 of CD4+ lymphocytes in TDLNs of patients with breast cancer produced IL-22. Among them, 0.64% ± 0.8 just produced IL-22 but were negative for IFNγ and IL-17. Statistical analysis indicated that the frequency of CD4+IL-22+ cells was significantly higher in the patients with stage III and the ones with 3-9 tumor involved lymph nodes (N2) compared to those with stage II and those having 1-3 tumor involved lymph nodes (N1) (P = 0.008 and P = 0.004, respectively).

CONCLUSION

The higher frequency of IL-22-producing cells in draining lymph nodes of patients with more advanced tumors (higher stage (stage III) and more involved lymph nodes) suggests a role for IL-22-producing cells in the tumor progression and invasion. However, further studies with larger sample size and more functional studies are needed to clarify the role of IL-22-producing cells in breast cancer pathogenesis.

Immune cell mediated cabozantinib resistance for patients with renal cell carcinoma

Renal cell carcinoma (RCC) is the third most common genitourinary cancer in the USA. Despite recent advances in the treatment for advanced and metastatic clear cell RCC (ccRCC), the 5-year relative survival rate for the distant disease remains at 12%. Cabozantinib, a tyrosine kinase inhibitor (TKI), which is one of the first-line therapies approved to treat advanced ccRCC as a single agent, is now being investigated as a combination therapy with newer immunotherapeutic agents. However, not much is known about how cabozantinib modulates the immune system. Here, we present a high throughput tri-culture model that incorporates cancer cells, endothelial cells, and patient-derived immune cells to study the effect of immune cells from patients with ccRCC on angiogenesis and cabozantinib resistance. We show that circulating immune cells from patients with ccRCC induce cabozantinib resistance via increased secretion of a set of pro-angiogenic factors. Using multivariate partial least square regression modeling, we identified CD4+ T cell subsets that are correlated with cabozantinib resistance and report the changes in the frequency of these populations in ccRCC patients who are undergoing cabozantinib therapy. These findings provide a potential set of biomarkers that should be further investigated in the current TKI-immunotherapy combination clinical trials to improve personalized treatments for patients with ccRCC.

The IL-22 gene rs2227478 polymorphism significantly decreases the risk of colorectal cancer in a Han Chinese population

To examine the role of IL-22 gene in colorectal cancer (CRC) susceptibility, we identified causative genetic polymorphisms in promoter region of IL-22 gene and explored the mechanism underlying their contribution to CRC development in a Chinese population of Hubei province. 13 target single nucleotide polymorphisms (SNPs) in IL-22 gene promoter were genotyped in 787 CRC patients (426 colon cancer and 361 rectal cancer) and 800 normal controls. The results demonstrated that the rs2227478 T > C polymorphism was significantly associated with the risk of colon cancer, rectal cancer and CRC, and the C allele was associated with a decreased cancer risk than the T allele. In CRC tissue samples, the subjects with CT+CC genotypes of rs2227478 had lower levels of IL-22 mRNA than the subjects with TT genotypes. Further functional analysis revealed that the transcription repressor Sp1 possessed a higher binding affinity to the C allele than the T allele. Collectively, the rs2227478 T > C is a functional genetic polymorphism that significantly reduces the CRC risk in a Han Chinese population.

IL-13Rα1 Suppresses Tumor Progression in Two-stage Skin Carcinogenesis Model by Regulating Regulatory T Cells

Type 2-inflammation-related cytokine Interleukin (IL)-13 plays a protective role in experimental papilloma induction in mice. To understand mechanisms by which IL-13 contributes to papilloma formation we utilized IL-13Rα1 knockout (KO) mice in widely used DMBA/TPA two-stage skin carcinogenesis protocol that mimics the development of Squamous Cell Carcinoma (SCC). KO mice developed more papillomas and significantly faster than wild-type (WT) mice. Papilloma development reduced Tregs in WT mice, but substantially less in KO mice. In line with this, IL-2 and IL-10 levels decreased in WT mice, but not in KO mice. Furthermore, systemic IL-5 and Thymic Stromal Lymphopoietin (TSLP) levels were elevated, while IL-22 was decreased during papilloma formation in the skin of KO mice. Polymorphonuclear Myeloid-derived suppressor cells (PMN-MDSCs) were decreased in the KO mice at the early phase of papilloma induction. We demonstrate that IL-13Rα1 protects from papilloma development in chemically induced skin carcinogenesis and our results provide further insights into the protective role of functional IL-4 and IL-13 signaling via type II IL-4R in tumor development.

The role of Th22 cells, from tissue repair to cancer progression

CD4⁺ T helper (Th) cells play a significant role in modulating host defense. In the presence of lineage specific cytokine cocktail, Naive CD4⁺ T cells can differentiate into several categories with distinct cytokines profile and effector functions. Th22 cells are a recently identified subset of CD4⁺ T cell, which differentiate from Naive CD4⁺ T in the presence of IL-6 and TNF-α. Th22 characterized by the production of interleukin-22 (IL-22) and expression of aryl hydrocarbon receptor (AHR). The main function of Th22 cells is to participate in mucosal defense, tissue repair, and wound healing. However, controversial data have shown that overexpression of IL-22 can lead to pathological changes under inflammatory conditions and tumor progression. This review summarizes our knowledge about the role of Th22 and IL-22 cells in tumor progression through induction of inflammation.

Interleukin-22 Deficiency Contributes to Dextran Sulfate Sodium-Induced Inflammation in Japanese Medaka, Oryzias latipes

Mucosal tissue forms the first line of defense against pathogenic microorganisms. Cellular damage in the mucosal epithelium may induce the interleukin (IL)-22-related activation of many immune cells, which are essential for maintaining the mucosal epithelial barrier. A previous study on mucosal immunity elucidated that mammalian IL-22 contributes to mucus and antimicrobial peptides (AMPs) production and anti-apoptotic function. IL-22 has been identified in several teleost species and is also induced in response to bacterial infections. However, the roles of IL-22 in teleost immunity and mucus homeostasis are poorly understood. In this study, Japanese medaka (Oryzias latipes) was used as a model fish. The medaka il22, il22 receptor A1 (il22ra1), and il22 binding protein (il22bp) were cloned and characterized. The expression of medaka il22, il22ra1, and il22bp in various tissues was measured using qPCR. These genes were expressed at high levels in the mucosal tissues of the intestines, gills, and skin. The localization of il22 and il22bp mRNA in the gills and intestines was confirmed by in situ hybridizations. Herein, we established IL-22-knockout (KO) medaka using the CRISPR/Cas9 system. In the IL-22-KO medaka, a 4-bp deletion caused a frameshift in il22. To investigate the genes subject to IL-22-dependent regulation, we compared the transcripts of larval medaka between wild-type (WT) and IL-22-KO medaka using RNA-seq and qPCR analyses. The comparison was performed not only in the naïve state but also in the dextran sulfate sodium (DSS)-exposed state. At the transcriptional level, 368 genes, including immune genes, such as those encoding AMPs and cytokines, were significantly downregulated in IL-22-KO medaka compared that in WT medaka in naïve states. Gene ontology analysis revealed that upon DSS stimulation, genes associated with cell death, acute inflammatory response, cell proliferation, and others were upregulated in WT medaka. Furthermore, in DSS-stimulated IL-22-KO medaka, wound healing was delayed, the number of apoptotic cells increased, and the number of goblet cells in the intestinal epithelium decreased. These results suggested that in medaka, IL-22 is important for maintaining intestinal homeostasis, and the disruption of the IL-22 pathway is associated with the exacerbation of inflammatory pathology, as observed for mammalian IL-22.

Interleukin-30 feeds breast cancer stem cells via CXCL10 and IL23 autocrine loops and shapes immune contexture and host outcome

Background

Breast cancer (BC) progression to metastatic disease is the leading cause of death in women worldwide. Metastasis is driven by cancer stem cells (CSCs) and signals from their microenvironment. Interleukin (IL) 30 promotes BC progression, and its expression correlates with disease recurrence and mortality. Whether it acts by regulating BCSCs is unknown and could have significant therapeutic implications.

Methods

Human (h) and murine (m) BCSCs were tested for their production of and response to IL30 by using flow cytometry, confocal microscopy, proliferation and sphere-formation assays, and PCR array. Immunocompetent mice were used to investigate the role of BCSC-derived IL30 on tumor development and host outcome. TCGA PanCancer and Oncomine databases provided gene expression data from 1084 and 75 hBC samples, respectively, and immunostaining unveiled the BCSC microenvironment.

Results

hBCSCs constitutively expressed IL30 as a membrane-anchored glycoprotein. Blocking IL30 hindered their proliferation and self-renewal efficiency, which were boosted by IL30 overexpression. IL30 regulation of immunity gene expression in human and murine BCSCs shared a significant induction of IL23 and CXCL10. Both immunoregulatory mediators stimulated BCSC proliferation and self-renewal, while their selective blockade dramatically hindered IL30-dependent BCSC proliferation and mammosphere formation. Orthotopic implantation of IL30-overexpressing mBCSCs, in syngeneic mice, gave rise to poorly differentiated and highly proliferating MYC⁺KLF4⁺LAG3⁺ tumors, which expressed CXCL10 and IL23, and were infiltrated by myeloid-derived cells, Foxp3⁺ T regulatory cells and NKp46⁺RORγt⁺ type 3 innate lymphoid cells, resulting in increased metastasis and reduced survival. In tumor tissues from patients with BC, expression of IL30 overlapped with that of CXCL10 and IL23, and ranked beyond the 95th percentile in a Triple-Negative enriched BC collection from the Oncomine Platform. CIBERSORTx highlighted a defective dendritic cell, CD4⁺ T and γδ T lymphocyte content and a prominent LAG3 expression in IL30^highversus IL30^low human BC samples from the TCGA PanCancer collection.

Conclusions

Constitutive expression of membrane-bound IL30 regulates BCSC viability by juxtacrine signals and via second-level mediators, mainly CXCL10 and IL23. Their autocrine loops mediate much of the CSC growth factor activity of IL30, while their paracrine effect contributes to IL30 shaping of immune contexture. IL30-related immune subversion, which also emerged from computational analyses, strongly suggests that targeting IL30 can restrain the BCSC compartment and counteract BC progression.

Bladder tumor ILC1s undergo Th17-like differentiation in human bladder cancer

PURPOSE

Human innate lymphoid cells (hILCs) are lineage-negative immune cells that do not express rearranged adaptive antigen receptors. Natural killer (NK) cells are hILCs that contribute to cancer defense. The role of non-NK hILCs in cancer is unclear. Our study aimed to characterize non-NK hILCs in bladder cancer.

EXPERIMENTAL DESIGN

Mass cytometry was used to characterize intratumoral non-NK hILCs based on 35 parameters, including receptors, cytokines, and transcription factors from 21 muscle-invasive bladder tumors. Model-based clustering was performed on t-distributed stochastic neighbor embedding (t-SNE) coordinates of hILCs, and the association of hILCs with tumor stage was analyzed.

RESULTS

Most frequent among intratumoral non-NK hILCs were hILC1s, which were increased in higher compared with lower stage tumors. Intratumoral hILC1s were marked by Th17-like phenotype with high RORγt, IL-17, and IL-22 compared to Th1 differentiation markers, including Tbet, perforin, and IFN-γ. Compared with intratumoral hILC2s and hILC3s, hILC1s also had lower expression of activation markers (NKp30, NKp46, and CD69) and increased expression of exhaustion molecules (PD-1 and Tim3). Unsupervised clustering identified nine clusters of bladder hILCs, which were not defined by the primary hILC subtypes 1-3. hILC1s featured in all the nine clusters indicating that intratumoral hILC1s displayed the highest phenotypic heterogeneity among all hILCs.

CONCLUSIONS

hILC1s are increased in higher stage tumors among patients with muscle-invasive bladder cancer. These intratumoral hILC1s exhibit an exhausted phenotype and Th17-like differentiation, identifying them as potential targets for immunotherapy.

Interleukins in cancer: from biology to therapy

Interleukins and associated cytokines serve as the means of communication for innate and adaptive immune cells as well as non-immune cells and tissues. Thus, interleukins have a critical role in cancer development, progression and control. Interleukins can nurture an environment enabling and favouring cancer growth while simultaneously being essential for a productive tumour-directed immune response. These properties of interleukins can be exploited to improve immunotherapies to promote effectiveness as well as to limit side effects. This Review aims to unravel some of these complex interactions.

Recent advances in the role of Th17/Treg cells in tumor immunity and tumor therapy

Th17 and Treg cells play an important role in regulating tissue inflammation and maintaining the stability of the immune system. They regulate inflammatory responses, participate in the occurrence and development of autoimmune diseases and tumors, and determine the disease progress. Malignant tumor is one of the diseases with the highest mortality rate in the world. However, the efficacy of traditional treatment is limited, so it is necessary to find safe and efficient treatment methods. Studies have shown that the balance of Th17/Treg cells plays a critical role in tumor progression. In this paper, we review the antitumor and tumor-suppressing effects of Th17/Treg cells, and new strategies for tumor therapy, combined with new research hotspots such as immune checkpoint therapy, miRNA-related gene therapy, and metabolic pathway regulation of Th17/Treg cell differentiation and tumor generation. The synergistic therapy is expected to be widely used in the future clinical practice, providing a new choice for the prevention and treatment of malignant tumors.

High IL-22RA1 gene expression is associated with poor outcome in muscle invasive bladder cancer

BACKGROUND

The cell surface interleukin 22 (IL-22) receptor complex is mainly expressed in epithelial and tissue cells like pancreatitis cells. Recent studies described that IL-22R was overexpressed in malignant diseases and was associated with a poor overall survival (OS). The role of IL-22RA1 gene expression in muscle invasive bladder cancer (MIBC) has not been investigated, yet.

OBJECTIVES

The aim of this study was to analyze the role of IL-22RA1 gene expression in patients with MIBC.

METHODS

In a cohort of 114 patients with MIBC who underwent radical cystectomy, IL-22RA1 gene expression was analyzed with qRT-PCR and correlated with clinical parameters. Furthermore, Kaplan-Meier and Cox regression analysis were performed. For validation, an in silico dataset (TCGA 2017, n=407) was reanalyzed.

RESULTS

IL-22RA1 gene expression was independent of clinicopathological parameters like age (P=0.2681), T stage (P=0.2130), nodal status (P=0.3238) and lymph vascular invasion (LVI, P=0.5860) in patients with MIBC. A high expression of IL-22RA1 was associated with a shorter OS (P=0.0040) and disease-specific survival (P=0.0385). Furthermore, a shorter disease-free survival (DFS) was also associated with a high expression of IL-22RA1 (P=0.0102). In the multivariable analysis, IL-22RA1 expression was an independent prognostic predictors regarding OS (P=0.0096, HR=0.48). In the TCGA cohort, IL-22RA1 expression was independent regarding to OS and DFS.

CONCLUSION

A high IL-22RA1 gene expression was associated with worse outcome. Furthermore, IL-22RA1 represented an independent predictor regarding OS in our cohort and therefore might be used for risk stratification in patients with MIBC.

STAT3 phosphorylation is required for the HepaCAM-mediated inhibition of castration-resistant prostate cancer cell viability and metastasis

BACKGROUND

Castration-resistant prostate cancer (CRPC) is an advanced disease that is difficult to treat, the mechanism of it is unclear. This study illustrated the function of hepatocyte cell adhesion molecule (HepaCAM) on CRPC cell viability and metastasis.

METHODS

The expression of HepaCAM and p-STAT3 in CRPC tissues were determined by immunohistochemistry and western blot analysis. Cell Counting Kit-8 and colony formation assays were deployed to analyze the growth ability of CRPC cells following the adenovirus-mediated re-expression of HepaCAM. CRPC cell migration and invasion capacity were investigated by wound healing and Matrigel-coated transwell assays, respectively. The messenger RNA or protein levels of p-STAT3, CyclinD1, cMyc, MMP2, MMP9, and VEGF were determined by reverse transcription (RT) followed by quantitative real-time polymerase chain reaction (RT-qPCR), and western blot analysis after either HepaCAM re-expression alone or in combination with IL-22 treatment. A CRPC orthotopic xenograft mouse model was applied to investigate the functional effect of HepaCAM on the metastasis of CRPC cells to the lungs.

RESULTS

The expression levels of HepaCAM were decreased while those of p-STAT3 were elevated in CRPC cells compare with surrounding benign tissues (p < .001). The overexpression of HepaCAM in CRPC cells notably reduced proliferation, migration, and invasion by inhibiting the expression of p-STAT3, CyclinD1, cMyc, MMP2, MMP9, and VEGF (p < .05). In addition, the expression of HepaCAM significantly inhibited the IL-22/p-STAT3 axis and the metastasis of CRPC cells to the lungs.

CONCLUSIONS

Our data suggested that HepaCAM suppressed the viability of CRPC cells via the IL-22/p-STAT3 axis and inhibited the metastasis of CRPC cells from the prostate to the lungs (p < .05).

Association between interleukin gene polymorphisms and susceptibility to gastric cancer in the Qinghai population

OBJECTIVE

To investigate the associations between interleukin (IL) gene polymorphisms and susceptibility to gastric cancer in the Qinghai population, China.

METHODS

Patients with gastric cancer and cancer-free controls were enrolled into the study from Qinghai Provincial People's Hospital between September 2016 and September 2018. Single nucleotide polymorphisms (SNPs) were genotyped with the Sequenom MassARRAY® SNP genotype system. The Hardy-Weinberg equilibrium in allele and genotype frequencies, and general characteristics between patients with gastric cancer and cancer-free controls, were evaluated using χ²-test. Potential associations between interleukin gene variants and the risk of gastric cancer were analysed by logistic regression.

RESULTS

Among eight candidate SNPs, the allele and genotype frequency distribution of IL-1B rs1143634 polymorphism was significantly different between patients with gastric cancer (n = 190) and cancer-free controls (n = 186). The IL-1B rs1143634 GA genotype and IL-1B rs1143634 GA + AA genotype were associated with a reduced risk of gastric cancer, however, the remaining SNPs were not statistically associated with gastric cancer risk in the Qinghai population.

CONCLUSION

The IL-1B rs1143634 polymorphism might be associated with a decreased risk of gastric cancer, and may be a protective factor against gastric cancer.

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.

Circulating Th22 cells, as well as Th17 cells, are elevated in patients with renal cell carcinoma

T-helper (Th) 22 cells serve an essential role in different types of tumors and autoimmune diseases. No research has been conducted to study the role of Th22 cells in the pathogenesis of renal cell carcinoma (RCC). We aimed to evaluate the prognostic value of circulating Th22, Th17, and Th1 cells in RCC patients. Thirty-two newly diagnosed RCC patients and thirty healthy controls were enlisted in the research. Their peripheral blood was collected, and the frequencies of circulating Th22, Th17, and Th1 cells were detected by flow cytometry. Plasma IL-22 concentrations were examined by an enzyme-linked immunosorbent assay (ELISA). Quantitative reverse transcription-polymerase chain reaction (RT-PCR) was used to identify the mRNA expression levels of aromatic hydrocarbon receptor (AHR) and RAR-associated orphan receptor C (RORC) in peripheral blood mononuclear cells (PBMC). Compared with the healthy control group, the frequency of circulating Th22 and Th17 cells and concentrations of plasma IL-22 were significantly increased in RCC patients. However, there was no significant difference in the frequency of Th1 cells. A positive correlation between Th22 cells and plasma IL-22 levels was found in RCC patients. Also, there was a significant positive correlation between Th22 and Th17 cells in RCC patients. An up-regulated expression of AHR and RORC transcription factors were also observed in RCC patients. As tumor stage and grade progressed, the frequencies of Th22 and Th17 cells and the level of plasma IL-22 significantly increased. Meanwhile, there was a positive correlation between Th22 and Th17 cells and RCC tumor stage or grade. Furthermore, patients with high Th22 or Th17 cells frequency displayed a decreased trend in survival rate. Our research indicated that the increased circulating Th22 and Th17 cells and plasma IL-22 may be involved in the pathogenesis of RCC and may be involved in the occurrence and development of tumors. Th22 cells, plasma IL-22, and Th17 cells may be promising new clinical biomarkers and may be used as cellular targets for RCC therapeutic intervention.

A Double Edged Sword Role of Interleukin-22 in Wound Healing and Tissue Regeneration

Wound healing and tissue regeneration is an intricate biological process that involves repair of cellular damage and maintenance of tissue integrity. Cascades involved in wound healing and tissue regeneration highly overlap with cancer causing pathways. Usually, subsequent tissue damage events include release of a number of cytokines to accomplish post-trauma restoration. IL-22 is one of the cytokines that are immediately produced to initiate immune response against several tissue impairments. IL-22 is a fundamental mediator in inflammation, mucous production, protective role against pathogens, wound healing, and tissue regeneration. However, accumulating evidence suggests pivotal role of IL-22 in instigation of various cancers due to its pro-inflammatory and tissue repairing activity. In this review, we summarize how healing effects of IL-22, when executed in an uncontrollable fashion can lead to carcinogenesis.

The Interleukin 22 Pathway Interacts with Mutant KRAS to Promote Poor Prognosis in Colon Cancer

PURPOSE

The cytokine IL22 promotes tumor progression in murine models of colorectal cancer. However, the clinical significance of IL22 in human colorectal cancer remains unclear. We sought to determine whether the IL22 pathway is associated with prognosis in human colorectal cancer, and to identify mechanisms by which IL22 can influence disease progression.

EXPERIMENTAL DESIGN

Transcriptomic data from stage II/III colon cancers in independent discovery (GSE39582 population-based cohort, N = 566) and verification (PETACC3 clinical trial, N = 752) datasets were used to investigate the association between IL22 receptor expression (encoded by the genes IL22RA1 and IL10RB), tumor mutation status, and clinical outcome using Cox proportional hazard models. Functional interactions between IL22 and mutant KRAS were elucidated using human colorectal cancer cell lines and primary tumor organoids.

RESULTS

Transcriptomic analysis revealed a poor-prognosis subset of tumors characterized by high expression of IL22RA1, the alpha subunit of the heterodimeric IL22 receptor, and KRAS mutation [relapse-free survival (RFS): HR = 2.93, P = 0.0006; overall survival (OS): HR = 2.45, P = 0.0023]. KRAS mutations showed a similar interaction with IL10RB and conferred the worst prognosis in tumors with high expression of both IL22RA1 and IL10RB (RFS: HR = 3.81, P = 0.0036; OS: HR = 3.90, P = 0.0050). Analysis of human colorectal cancer cell lines and primary tumor organoids, including an isogenic cell line pair that differed only in KRAS mutation status, showed that IL22 and mutant KRAS cooperatively enhance cancer cell proliferation, in part through augmentation of the Myc pathway.

CONCLUSIONS

Interactions between KRAS and IL22 signaling may underlie a previously unrecognized subset of clinically aggressive colorectal cancer that could benefit from therapeutic modulation of the IL22 pathway.

Gene Expression Network Analysis of Precursor Lesions in Familial Pancreatic Cancer

Purpose: High-grade pancreatic intraepithelial neoplasia (PanIN) are aggressive premalignant lesions, associated with risk of progression to pancreatic ductal adenocarcinoma (PDAC). A depiction of co-dysregulated gene activity in high-grade familial pancreatic cancer (FPC)-related PanIN lesions may characterize the molecular events during the progression from familial PanIN to PDAC. Materials and Methods: We performed weighted gene coexpression network analysis (WGCNA) to identify clusters of coexpressed genes associated with FPC-related PanIN lesions in 13 samples with PanIN-2/3 from FPC predisposed individuals, 6 samples with PDAC from sporadic pancreatic cancer (SPC) patients, and 4 samples of normal donor pancreatic tissue. Results: WGCNA identified seven differentially expressed gene (DEG) modules and two commonly expressed gene (CEG) modules with significant enrichment for Gene Ontology (GO) terms in FPC and SPC, including three upregulated (p < 5e-05) and four downregulated (p < 6e-04) gene modules in FPC compared to SPC. Among the DEG modules, the upregulated modules include 14 significant genes (p < 1e-06): ALOX12-AS1, BCL2L11, EHD4, C4B, BTN3A3, NDUFA11, RBM4B, MYOC, ZBTB47, TTTY15, NAPRT, LOC102606465, LOC100505711, and PTK2. The downregulated modules include 170 genes (p < 1e-06), among them 13 highly significant genes (p < 1e-10): COL10A1, SAMD9, PLPP4, COMP, POSTN, IGHV4-31, THBS2, MMP9, FNDC1, HOPX, TMEM200A, INHBA, and SULF1. The DEG modules are enriched for GO terms related to mitochondrial structure and adenosine triphosphate metabolic processes, extracellular structure and binding properties, humoral and complement mediated immune response, ligand-gated ion channel activity, and transmembrane receptor activity. Among the CEG modules, IL22RA1, DPEP1, and BCAT1 were found as highly connective hub genes associated with both FPC and SPC. Conclusion: FPC-related PanIN lesions exhibit a common molecular basis with SPC as shown by gene network activities and commonly expressed high-connectivity hub genes. The differential molecular pathology of FPC and SPC involves multiple coexpressed gene clusters enriched for GO terms including extracellular activities and mitochondrion function.

IL-10 and IL-22 in Mucosal Immunity: Driving Protection and Pathology

The barrier surfaces of the gastrointestinal tract are in constant contact with various microorganisms. Cytokines orchestrate the mucosal adaptive and innate immune cells in the defense against pathogens. IL-10 and IL-22 are the best studied members of the IL-10 family and play essential roles in maintaining mucosal homeostasis. IL-10 serves as an important regulator in preventing pro-inflammatory responses while IL-22 plays a protective role in tissue damage and contributes to pathology in certain settings. In this review, we focus on these two cytokines in the development of gastrointestinal diseases, including inflammatory bowel diseases (IBD) and colitis-associated cancer (CAC). We summarize the recent studies and try to gain a better understanding on how they regulate immune responses to maintain equilibrium under inflammatory conditions.

Ambiguous roles and potential therapeutic strategies of innate lymphoid cells in different types of tumor

Recent years have witnessed a significant development in the current understanding of innate lymphoid cells (ILCs) and their roles in the innate immune system, where they regulate tissue homeostasis, inflammation, as well as tumor surveillance and tumorigenesis. Based on the limited studies of ILCs in cancer, ILCs may be classified into three subgroups depending on their phenotypic and functional characteristics: Group 1 ILCs, which include natural killer cells and ILC1s; Group 2 ILCs, which only contain ILC2s and Group 3 ILCs, which comprise of LTi cells and ILC3s. Group 1 ILCs predominantly exert antitumor activities, while Group 2 ILCs and Group 3 ILCs are predominantly procarcinogenic in nature. In different types of tumor, each ILC subset behaves differently. Current research is focused on investigating how ILCs may be manipulated and employed as therapeutic strategies for the treatment of cancer. The present review aimed to summarize the characteristics and effects of ILCs in the context of tumor immunology, and provide novel insight into the pro- or anti-tumor activities of ILCs in different types of malignancy, including solid tumors, such as those in the gastrointestinal tract, lung, breast, bladder or prostate, as well as melanoma, further to hematological malignancies, with the aim to highlight potential therapeutic targets for the treatment of cancer.

Interleukin-22 regulates gastric cancer cell proliferation through regulation of the JNK signaling pathway

Inflammation is considered as one of the major hallmarks of cancer and is associated with gastric cancer. Interleukin-22 (IL-22), a member of the IL-10 family, serves an important role in inflammatory diseases and tumors. The aim of the present study was to examine the effects of IL-22 on the proliferation of gastric cancer cells (AGS cells) in vitro and explore the associated molecular mechanism. The results of a Cell Counting kit-8 assay using AGS cells transfected with an IL-22-plasmid indicated that IL-22 could promote AGS cell viability. However, when IL-22 was knocked down by IL-22-short hairpin (sh)RNA, the viability of AGS cells was significantly impaired. Western blotting results indicated that IL-22 decreased the activation of the mitogen-activated protein kinase (MAPK) signaling pathway. Furthermore, IL-22-shRNA transfection increased the activation of MAPK, as evidenced by the upregulated phosphorylation of ERK and JNK. Taken together, the results of the present study suggest that IL-22 regulated the viability of gastric cancer cells through the JNK signaling pathway, suggesting a therapeutic approach for gastric cancer via targeting IL-22.

Interleukin 22 Signaling Regulates Acinar Cell Plasticity to Promote Pancreatic Tumor Development in Mice

BACKGROUND & AIMS

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy that invades surrounding structures and metastasizes rapidly. Although inflammation is associated with tumor formation and progression, little is known about the mechanisms of this connection. We investigate the effects of interleukin (IL) 22 in the development of pancreatic tumors in mice.

METHODS

We performed studies with Pdx1-Cre;LSL-KrasG12D;Trp53+/-;Rosa26EYFP/+ (PKCY) mice, which develop pancreatic tumors, and PKCY mice with disruption of IL22 (PKCY Il22-/-mice). Pancreata were collected at different stages of tumor development and analyzed by immunohistochemistry, immunoblotting, real-time polymerase chain reaction, and flow cytometry. Some mice were given cerulean to induce pancreatitis. Pancreatic cancer cell lines (PD2560) were orthotopically injected into C57BL/6 mice or Il22-/-mice, and tumor development was monitored. Pancreatic cells were injected into the tail veins of mice, and lung metastases were quantified. Acini were collected from C57BL/6 mice and resected human pancreata and were cultured. Cell lines and acini cultures were incubated with IL22 and pharmacologic inhibitors, and protein levels were knocked down with small hairpin RNAs. We performed immunohistochemical analyses of 26 PDACs and 5 nonneoplastic pancreas specimens.

RESULTS

We observed increased expression of IL22 and the IL22 receptor (IL22R) in the pancreas compared with other tissues in mice; IL22 increased with pancreatitis and tumorigenesis. Flow cytometry indicated that the IL22 was produced primarily by T-helper 22 cells. PKCY Il22-/-mice did not develop precancerous lesions or pancreatic tumors. The addition of IL22 to cultured acinar cells increased their expression of markers of ductal metaplasia; these effects of IL22 were prevented with inhibitors of Janus kinase signaling to signal transducer and activator of transcription (STAT) (ruxolitinib) or mitogen-activated protein kinase kinase (MEK) (trametinib) and with STAT3 knockdown. Pancreatic cells injected into Il22-/- mice formed smaller tumors than those injected into C57BL/6. Incubation of IL22R-expressing PDAC cells with IL22 promoted spheroid formation and invasive activity, resulting in increased expression of stem-associated transcription factors (GATA4, SOX2, SOX17, and NANOG), and increased markers of the epithelial-mesenchymal transition (CDH1, SNAI2, TWIST1, and beta catenin); ruxolitinib blocked these effects. Human PDAC tissues had higher levels of IL22, phosphorylated STAT3, and markers of the epithelial-mesenchymal transition than nonneoplastic tissues. An increased level of STAT3 in IL22R-positive cells was associated with shorter survival times of patients.

CONCLUSIONS

We found levels of IL22 to be increased during pancreatitis and pancreatic tumor development and to be required for tumor development and progression in mice. IL22 promotes acinar to ductal metaplasia, stem cell features, and increased expression of markers of the epithelial-mesenchymal transition; inhibitors of STAT3 block these effects. Increased expression of IL22 by PDACs is associated with reduced survival times.

Lack of association between interleukin-22 gene polymorphisms and cancer risk: a case-control study and a meta-analysis

BACKGROUND

Interleukin-22 (IL22) has been implicated in inflammation and tumorigenesis. The association between IL22 gene polymorphisms and cancer risk has been widely explored. However, the limited sample sizes of previous studies may produce inadequate statistical power and conflicting results, which calls for further investigations. In this study, we recruited a total of 1490 cancer patients (480 liver cancer patients, 550 lung cancer patients, and 460 gastric cancer patients) and 800 normal controls to explore the associations between IL22 gene polymorphisms (rs1179251, rs2227485, rs2227511, and rs2227473) and cancer risk.

METHOD

The genotyping was performed with polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and Sanger sequencing.

RESULTS

Our results showed that none of the four IL22 gene polymorphisms was associated with the risk of liver, lung or gastric cancer in Hubei Han Chinese population. To improve the statistical strength, a meta-analysis was further conducted. The results further confirmed our present findings and showed that rs1179251, rs2227485, and rs2227473 were not associated with cancer risk in total or stratified analysis.

CONCLUSION

Consequently, the rs1179251, rs2227485, rs2227511, and rs2227473 polymorphisms may not be associated with cancer risk. However, further investigations using larger samples in different ethnic populations are required.

IL6 Induces an IL22+ CD8+ T-cell Subset with Potent Antitumor Function

CD8+ T cells can be polarized into several different subsets as defined by the cytokines they produce and the transcription factors that govern their differentiation. Here, we identified the polarizing conditions to induce an IL22-producing CD8+ Tc22 subset, which is dependent on IL6 and the aryl hydrocarbon receptor transcription factor. Further characterization showed that this subset was highly cytolytic and expressed a distinct cytokine profile and transcriptome relative to other subsets. In addition, polarized Tc22 were able to control tumor growth as well as, if not better than, the traditional IFNγ-producing Tc1 subset. Tc22s were also found to infiltrate the tumors of human patients with ovarian cancer, comprising up to approximately 30% of expanded CD8+ tumor-infiltrating lymphocytes (TIL). Importantly, IL22 production in these CD8+ TILs correlated with improved recurrence-free survival. Given the antitumor properties of Tc22 cells, it may be prudent to polarize T cells to the Tc22 lineage when using chimeric antigen receptor (CAR)-T or T-cell receptor (TCR) transduction-based immunotherapies.

IL-17-Producing Cells in Tumor Immunity: Friends or Foes?

IL-17 is produced by RAR-related orphan receptor gamma t (RORγt)-expressing cells including Th17 cells, subsets of γδT cells and innate lymphoid cells (ILCs). The biological significance of IL-17-producing cells is well-studied in contexts of inflammation, autoimmunity and host defense against infection. While most of available studies in tumor immunity mainly focused on the role of T-bet-expressing cells, including cytotoxic CD8⁺ T cells and NK cells, and their exhaustion status, the role of IL-17-producing cells remains poorly understood. While IL-17-producing T-cells were shown to be anti-tumorigenic in adoptive T-cell therapy settings, mice deficient in type 17 genes suggest a protumorigenic potential of IL-17-producing cells. This review discusses the features of IL-17-producing cells, of both lymphocytic and myeloid origins, as well as their suggested pro- and/or anti-tumorigenic functions in an organ-dependent context. Potential therapeutic approaches targeting these cells in the tumor microenvironment will also be discussed.

Intratumoral IL22-producing cells define immunoevasive subtype muscle-invasive bladder cancer with poor prognosis and superior nivolumab responses

Our previous researches have identified immunoevasive subtype muscle-invasive bladder cancer (MIBC) characterized with immune cells infiltration patterns. Our study explored the clinical significance, immunoregulatory role and therapeutic value of intratumoral IL22-producing cells in MIBC. Two hundred and fifty-nine formalin-fixed paraffin-embedded MIBC samples and 83 freshly resected MIBC tissues and 391 TCGA MIBC samples were retrospectively evaluated. Immunohistochemistry and flow cytometry were applied to identify immune cell infiltration and functional status. In vitro intervention studies were to test the therapeutic and predictive potential of IL22+ cells. Our data revealed patients with high IL22+ cells infiltration suffered poor overall survival and recurrence-free survival in both training and validation cohorts. Only pT2 patients of combined cohort with low IL22+ cells infiltration gained survival benefits from adjuvant chemotherapy (ACT) significantly. Besides, immune contexture featured with increased pro-tumor cells and immunosuppressive cytokines was identified in patients with high IL22+ cells density. The expression pattern of exhausted and effector markers in CD8+ T cells from high IL22+ cells subgroup indicated their dysfunctional status. Importantly, nivolumab showed tumor-killing efficacy in tumors with high IL22+ cells infiltration, and immunosuppressive contexture with CD8+ T cells exhaustion was abrogated in tumors treated with anti-IL22 antibody. In summary, IL22+ cells infiltration determined immunosuppressive contexture with CD8+ T cell dysfunction. Tumor-infiltrating IL22+ cells could be used as an independent marker to predict prognosis and ACT responses. IL22+ cells infiltration possessed the potential to be a favorable predictor for nivolumab application and IL22 blockade could be a novel therapeutic strategy in MIBC.

TYK2 in Tumor Immunosurveillance

We review the history of the tyrosine kinase 2 (TYK2) as the founding member of the Janus kinase (JAK) family and outline its structure-function relation. Gene-targeted mice and hereditary defects of TYK2 in men have established the biological and pathological functions of TYK2 in innate and adaptive immune responses to infection and cancer and in (auto-)inflammation. We describe the architecture of the main cytokine receptor families associated with TYK2, which activate signal transducers and activators of transcription (STATs). We summarize the cytokine receptor activities with well characterized dependency on TYK2, the types of cells that respond to cytokines and TYK2 signaling-induced cytokine production. TYK2 may drive beneficial or detrimental activities, which we explain based on the concepts of tumor immunoediting and the cancer-immunity cycle in the tumor microenvironment. Finally, we summarize current knowledge of TYK2 functions in mouse models of tumor surveillance. The biology and biochemistry of JAKs, TYK2-dependent cytokines and cytokine signaling in tumor surveillance are well covered in recent reviews and the oncogenic properties of TYK2 are reviewed in the recent Special Issue ‘Targeting STAT3 and STAT5 in Cancer’ of Cancers.

Interleukin-22 promotes development of malignant lesions in a mouse model of spontaneous breast cancer

Interleukin (IL)-22 is recognized as a tumor-supporting cytokine and is implicated in the proliferation of multiple epithelial cancers. In breast cancer, the current knowledge of IL-22 function is based on cell line models and little is known about how IL-22 affects the tumor initiation, proliferation, invasion, and metastasis in the in vivo system. Here, we investigated the tumor stage-specific function of IL-22 in disease development by evaluating the stage-by-stage progression of breast cancer in an IL-22 knockout spontaneous breast cancer mouse model. We found that among all the stages, IL-22 is specifically upregulated in tumor microenvironment (TME) during the malignant transformation stage of breast tumor progression. The deletion of IL-22 gene leads to the arrest of malignant transition stage, and reduced invasion and tumor burden. Administration of recombinant IL-22 in the TME does not influence in vivo tumor initiation and proliferation but only promotes malignant transformation of cancer cells. Mechanistically, deletion of IL-22 gene causes downregulation of epithelial-to-mesenchymal transition (EMT)-associated transcription factors in breast tumors, suggesting EMT as the mechanism of regulation of malignancy by IL-22. Clinically, in human breast tumor tissues, increased number of IL-22+ cells in the TME is associated with an aggressive phenotype of breast cancer. For the first time, this study provides an insight into the tumor stage-specific function of IL-22 in breast tumorigenesis.