Interleukin-10 inhibits tumor metastasis through an NK cell-dependent mechanism

Oleanolic acid inhibits the tumor progression by regulating Lactobacillus through the cytokine-cytokine receptor interaction pathway in 4T1-induced mice breast cancer model

The therapeutic mechanism of oleanolic acid (OA) in breast cancer has been widely reported, but little has been known about the combined effects of transcriptome and gut microbiome. In this study, the phenotypic effect of oleanolic acid on mice was tested at the end of the administration cycle, and RNA sequencing on murine tumor tissue and 16S-rRNA sequencing on intestinal contents were conducted to analyze gene expression profiles and microbial diversity between the control group and OA treated group using 4T1-induced mice breast cancer model. As a result, it has been confirmed that oleanolic acid would play a significant inhibitory effect on the development of breast tumors in mice. Based on the integrative analysis of the transcriptomic and metagenomic data, it was found that the abundance of Lactobacillus in the intestinal flora of mice significantly increased in the OA group. Moreover, the up-regulation of Il10 had a significant effect on inhibiting the tumor progression, which played a role through cytokine-cytokine receptor interaction pathway.

An important call: Suggestion of using IL-10 as therapeutic agent for COVID-19 with ARDS and other complications

The global coronavirus disease 2019 (COVID-19) pandemic has a detrimental impact on public health. COVID-19 usually manifests as pneumonia, which can progress into acute respiratory distress syndrome (ARDS) related to uncontrolled TH17 immune reaction. Currently, there is no effective therapeutic agent to manage COVID-19 with complications. The currently available anti-viral drug remdesivir has an effectiveness of 30% in SARS-CoV-2-induced severe complications. Thus, there is a need to identify effective agents to treat COVID-19 and the associated acute lung injury and other complications. The host immunological pathway against this virus typically involves the THαβ immune response. THαβ immunity is triggered by type 1 interferon and interleukin-27 (IL-27), and the main effector cells of the THαβ immune response are IL10-CD4 T cells, CD8 T cells, NK cells, and IgG1-producing B cells. In particular, IL-10 exerts a potent immunomodulatory or anti-inflammatory effect and is an anti-fibrotic agent for pulmonary fibrosis. Concurrently, IL-10 can ameliorate acute lung injury or ARDS, especially those caused by viruses. Owing to its anti-viral activity and anti-pro-inflammatory effects, in this review, IL-10 is suggested as a possible treatment agent for COVID-19.

The Anti-Cancer Activity of the Naturally Occurring Dipeptide Carnosine: Potential for Breast Cancer

Carnosine is an endogenous dipeptide composed of β-alanine and L-histidine, possessing a multimodal pharmacodynamic profile that includes anti-inflammatory and anti-oxidant activities. Carnosine has also shown its ability to modulate cell proliferation, cell cycle arrest, apoptosis, and even glycolytic energy metabolism, all processes playing a key role in the context of cancer. Cancer is one of the most dreaded diseases of the 20th and 21st centuries. Among the different types of cancer, breast cancer represents the most common non-skin cancer among women, accounting for an estimated 15% of all cancer-related deaths in women. The main aim of the present review was to provide an overview of studies on the anti-cancer activity of carnosine, and in particular its activity against breast cancer. We also highlighted the possible advantages and limitations involved in the use of this dipeptide. The first part of the review entailed a brief description of carnosine's biological activities and the pathophysiology of cancer, with a focus on breast cancer. The second part of the review described the anti-tumoral activity of carnosine, for which numerous studies have been carried out, especially at the preclinical level, showing promising results. However, only a few studies have investigated the therapeutic potential of this dipeptide for breast cancer prevention or treatment. In this context, carnosine has shown to be able to decrease the size of cancer cells and their viability. It also reduces the levels of vascular endothelial growth factor (VEGF), cyclin D1, NAD+, and ATP, as well as cytochrome c oxidase activity in vitro. When tested in mice with induced breast cancer, carnosine proved to be non-toxic to healthy cells and exhibited chemopreventive activity by reducing tumor growth. Some evidence has also been reported at the clinical level. A randomized phase III prospective placebo-controlled trial showed the ability of Zn-carnosine to prevent dysphagia in breast cancer patients undergoing adjuvant radiotherapy. Despite this evidence, more preclinical and clinical studies are needed to better understand carnosine's anti-tumoral activity, especially in the context of breast cancer.

A CSF-1R-blocking antibody/IL-10 fusion protein increases anti-tumor immunity by effectuating tumor-resident CD8+ T cells

Strategies to increase intratumoral concentrations of an anticancer agent are desirable to optimize its therapeutic potential when said agent is efficacious primarily within a tumor but also have significant systemic side effects. Here, we generate a bifunctional protein by fusing interleukin-10 (IL-10) to a colony-stimulating factor-1 receptor (CSF-1R)-blocking antibody. The fusion protein demonstrates significant antitumor activity in multiple cancer models, especially head and neck cancer. Moreover, this bifunctional protein not only leads to the anticipated reduction in tumor-associated macrophages but also triggers proliferation, activation, and metabolic reprogramming of CD8+ T cells. Furthermore, it extends the clonotype diversity of tumor-infiltrated T cells and shifts the tumor microenvironment (TME) to an immune-active state. This study suggests an efficient strategy for designing immunotherapeutic agents by fusing a potent immunostimulatory molecule to an antibody targeting TME-enriched factors.

Roles of benefit finding in psychological and inflammatory adjustments in persons with colorectal cancer: a prospective analysis on the multidimensionality of benefit finding

OBJECTIVE

This study examined the unique associations of different dimensions of the resilience factor, benefit finding, on concurrent and prospective psychological and biological adjustment outcomes over the first year after a colorectal cancer diagnosis.

METHODS AND MEASURES

Individuals newly diagnosed with colorectal cancer (n = 133, mean age = 56 years old, 59% female, 46% Hispanic) completed questionnaires assessing the multidimensional aspects of benefit finding around 4 months post-diagnosis (T1). Psychological (depressive symptoms and life satisfaction) and biological [C-reactive protein (CRP) and interleukin-10 (IL-10)] adjustments were assessed at T1 and one-year post-diagnosis (T2).

RESULTS

Structural equation modeling revealed that at T1, greater reprioritization was concurrently related to higher depressive symptoms (p=.020). Lower acceptance, lower empathy, and greater positive self-view predicted higher life satisfaction at T2 (ps<.010). Additionally, lower empathy and greater family valuation predicted higher CRP at T2 (ps<.004), whereas greater positive self-view predicted higher IL-10 at T2 (p=.039). Greater overall benefit finding was associated with lower IL-10 at T1 (p=.013).

CONCLUSION

Various aspects of benefit finding differentially relate to psychological and inflammatory markers during the first year after diagnosis in persons with colorectal cancer. Interventions designed to specifically enhance positive self-view may promote both the psychological and biological health of individuals with cancer.

Emerging interleukin targets in the tumour microenvironment: implications for the treatment of gastrointestinal tumours

The effectiveness of antitumour immunity is dependent on intricate cytokine networks. Interleukins (ILs) are important mediators of complex interactions within the tumour microenvironment, including regulation of tumour-infiltrating lymphocyte proliferation, differentiation, migration and activation. Our evolving and increasingly nuanced understanding of the cell type-specific and heterogeneous effects of IL signalling has presented unique opportunities to fine-tune elaborate IL networks and engineer new targeted immunotherapeutics. In this review, we provide a primer for clinicians on the challenges and potential of IL-based treatment. We specifically detail the roles of IL-2, IL-10, IL-12 and IL-15 in shaping the tumour-immune landscape of gastrointestinal malignancies, paying particular attention to promising preclinical findings, early-stage clinical research and innovative therapeutic approaches that may properly place ILs to the forefront of immunotherapy regimens.

PEGylated IL-10: Clinical Development in Cancer Immunotherapy, Where to Go?

PURPOSEOF REVIEW

The purpose of this review is to discuss the current understanding of the pegilodecakin (PEGylated interleukin 10) and its role in the inhibition of tumour growth and metastasis. This review also focuses on clinical data published to date that have evaluated the efficacy and safety of pegilodecakin.

RECENT FINDINGS

Pegilodecakin has shown significant promise in preclinical models, notable for decreased tumour burden and fewer sites of metastatic disease across various malignancies. It has been most widely assessed in a phase I/Ib clinical trial against several solid tumours, leading to the phase II and III clinical trials containing pegilodecakin and its combination with other current treatments. However, the updated data have not shown higher efficacy in renal cell carcinoma, metastatic non-small cell lung cancer or pancreatic cancer, with respect to the controls, yet the adverse events presented more mixed results. Further investigation into combination therapies including pegilodecakin is ongoing. Pegilodecakin showed promise in preclinical and phase I clinical trials on its efficacy in several solid tumours, with expected regulation of IL-10 signalling pathway observed. However, the phase II and III trials did not justify its application as potential immunotherapy in selected cancers. Further evaluation of pegilodecakin's efficacy in other cancers, either as monotherapy or in combination with the current treatments, is worth investigating clinically, which warrants to better understand its potential clinical utility.

Comparative analysis of the immune response to RFA and cryoablation in a colon cancer mouse model

The immune response to radiofrequency ablation (RFA) and cryoablation (CRA) was characterized and compared in a colon cancer mouse model. All studies were conducted under a research protocol approved by the National Institutes of Health, Clinical Center, Animal Care and Use Committee. BALB/cJ mice were inoculated with CT26 cells, and randomized to RFA, CRA, or sham treatment. Mice were sacrificed 3 days post-treatment, and tumor, spleen, and serum were harvested. Cell death was determined by Caspase-3 immunohistochemical and TUNEL stains. Immune response was analyzed using flow cytometry, serum cytokine assay and immunohistochemistry. Cell death, necrosis, and apoptosis induced by ablation were comparable in RFA and CRA. Decreased frequency of systemic T-regulatory cells was found in the CRA group. Both RFA and CRA reduced frequencies of several myeloid-derived suppressor cell (MDSC) subpopulations. RFA induced pro-inflammatory cytokine secretion including TNF-α and IL-12 as well as anti-inflammatory cytokines IL-5, and IL-10. CRA augmented secretion of a wider array of cytokines compared to RFA with both pro- and anti-inflammatory properties including IL-1β, IL-5, IL-6, IL-10, and KC GRO. In the tumor microenvironment, RFA reduced the number of T-regulatory cells, a finding not observed with CRA. Reduction of immune suppression via decreases in T-regulatory cells and MDSC was found to be induced by RFA or CRA. CRA augmented a wider range of cytokines than RFA, which were mainly pro-inflammatory, but also anti-inflammatory. In the tumor microenvironment, RFA demonstrated more pronounced anti-tumoral immunity. Further delineation of specific immunomodulation induced by ablation could inform drug-device development and may play a role in future hypothesis-driven immunomodulatory paradigms that combine immunotherapy drugs with tumor destruction for the treatment of metastatic colon cancer.

IL-10 in cancer: an essential thermostatic regulator between homeostatic immunity and inflammation - a comprehensive review

Cytokines are soluble proteins that mediate intercellular signaling regulating immune and inflammatory responses. Cytokine modulation represents a promising cancer immunotherapy approach for immune-mediated tumor regression. However, redundancy in cytokine signaling and cytokines' pleiotropy, narrow therapeutic window, systemic toxicity, short half-life and limited efficacy represent outstanding challenges for cytokine-based cancer immunotherapies. Recently, there has been interest in the paradoxical role of IL-10 in cancer, its controversial prognostic utility and novel strategies to enhance its therapeutic profile. Here, the authors review the literature surrounding the role of IL-10 within the tumor microenvironment, its prognostic correlates to cancer patient outcomes and its pro- and antitumor effects, and they assess the legitimacy of potential therapeutic strategies harnessing IL-10 by outlining the notable preclinical and clinical evidence to date.

Tumor: Stroma Interaction and Cancer

The understanding of how normal cells transform into tumor cells and progress to invasive cancer and metastases continues to evolve. The tumor mass is comprised of a heterogeneous population of cells that include recruited host immune cells, stromal cells, matrix components, and endothelial cells. This tumor microenvironment plays a fundamental role in the acquisition of hallmark traits, and has been the intense focus of current research. A key regulatory mechanism triggered by these tumor-stroma interactions includes processes that resemble epithelial-mesenchymal transition, a physiologic program that allows a polarized epithelial cell to undergo biochemical and cellular changes and adopt mesenchymal cell characteristics. These cellular adaptations facilitate enhanced migratory capacity, invasiveness, elevated resistance to apoptosis, and greatly increased production of ECM components. Indeed, it has been postulated that cancer cells undergo epithelial-mesenchymal transition to invade and metastasize.In the following discussion, the physiology of chronic inflammation, wound healing, fibrosis, and tumor invasion will be explored. The key regulatory cytokines, transforming growth factor β and osteopontin, and their roles in cancer metastasis will be highlighted.

Interpreting 'anti-inflammatory' cytokine responses to exercise: focus on interleukin-10

Circulating concentrations of canonically pro- and anti-inflammatory cytokines are commonly measured when evaluating the anti-inflammatory effects of exercise. An important caveat to interpreting systemic cytokine concentrations as evidence for the anti-inflammatory effects of exercise is the observed dissociation between circulating cytokine concentrations and cytokine function at the tissue/cellular level. The dichotomization of cytokines as pro- or anti-inflammatory also overlooks the context dependence of cytokine function, which can vary depending on the physiological state being studied, the cytokine's cellular source/target, and magnitude of cytokine responses. We re-evaluate our current understanding of anti-inflammatory cytokine responses to exercise by highlighting nuances surrounding the interpretation of altered systemic cytokine concentrations as evidence for changes in inflammatory processes occurring at the tissue/cellular level. We highlight the lesser known pro-inflammatory and immunostimulatory actions of the prototypical anti-inflammatory cytokine, interleukin (IL)-10, including the potentiation of interferon gamma production during endotoxaemia, CD8⁺ T cell activation in tumour bearing rodents and cancer patients in vivo, and CD8⁺ T lymphocyte and natural killer cell activation in vitro. IL-10's more well-established anti-inflammatory actions can also be blunted following exercise training and under chronic inflammatory states such as type 2 diabetes (T2D) independently of circulating IL-10 concentrations. The resistance to IL-10's anti-inflammatory action in T2D coincides with blunted STAT3 phosphorylation and can be restored with small-molecule activators of IL-10 signalling, highlighting potential therapeutic avenues for restoring IL-10 action. We posit that inferences based on altered circulating cytokine concentrations alone can miss important functional changes in cytokine action occurring at the tissue/cellular level.

Elevation of Pro-inflammatory and Anti-inflammatory Cytokines in Rat Serum after Acute Methamphetamine Treatment and Traumatic Brain Injury

The use of methamphetamine (METH) is a growing worldwide epidemic that bears grave societal implications. METH is known to exert its neurotoxic effects on the dopaminergic and serotonergic systems of the brain. In addition to this classical studied mechanism of damage, findings from our laboratory and others have shown that acute METH treatment and mechanical injury, i.e. traumatic brain injury (TBI), share common cell injury mechanism(s). Since neuro-inflammation is a signature event in TBI, we hypothesize that certain cytokine levels might also be altered in rat brain exposed to an acute METH insult. In this study, using a cytokine antibody array chip, we evaluated the serum levels of 19 cytokines in rats 24 h after exposure to a 40 mg/kg acute regimen of METH. Data were compared to rats subjected to experimental TBI using the controlled cortical impact (CCI) injury model and saline controls. Sandwich ELISA method was used to further validate some of the findings obtained from the antibody cytokine array. We confirmed that three major inflammatory-linked cytokines (IL-1β, IL-6, and IL-10) were elevated in the METH and TBI groups compared to the saline group. Such finding suggests the involvement of an inflammatory process in these brain insults, indicating that METH use is, in fact, a stressor to the immune system where systemic involvement of an altered cytokine profile may play a major role in mediating chemical brain injury after METH use.

Interleukin-10-592 polymorphism: impact on relapse and survival after allogeneic hematopoietic stem cell transplantation in children with hematological malignancies

Purpose

Interleukin-10 (IL-10) potentially can promote the development of alloimmunity. The aim of this study was to investigate if the IL-10-592 CC genotype in the donor reduces the risk of relapse after hematopoietic stem cell transplantation (HSCT) and if that has an impact on event-free survival (EFS) and overall survival (OS).

Methods

A cohort of 211 children with acute lymphoblastic leukemia (n = 99), acute myeloid leukemia (n = 69), myelodysplastic syndrome (n = 31) or chronic myeloid leukemia (n = 12) who underwent hematopoietic stem cell transplantation (HSCT) in a single center and their respective donors were genotyped of IL-10 gene for rs1800872 using TaqMan real-time polymerase chain reaction.

Results

The IL-10-592 CC genotype was detected in 107 of the 211 donors (50.7%) and in 106 of the 211 patients (50.2%). Genotype AC was found in 95 donors (45.0%) and in 90 patients (42.7%). Nine donors (4.3%) and 15 patients (7.1%) were homozygous for AA. Ultimately, we observed a significantly reduced incidence of relapse rate (RR) in patients who were transplanted from a donor with the IL-10-592 CC genotype (19% versus 43% (AC) versus 49% (AA); P = 0.0007). In addition, a significant increase of EFS (P = 0.004) and OS (P = 0.006) was detected if the IL-10-592 CC genotype is present in the donor. The occurrence of the IL-10-592 CC genotype, in either donors or recipients, had no significant impact on acute and chronic graft-versus-host disease. In addition, the IL-10-592 genotype of the recipients was not relevant for the RR (P = 0.47434), the EFS (P = 0.840), and the OS (P = 0.535).

Conclusion

The IL-10-592 CC genotype in the donor was associated with a significant decrease of RR which led to a significant increase of EFS and OS after HSCT. This is the first study to describe an association of the IL-10 gene polymorphism with RR, EFS, and OS after HSCT. Selecting a donor with the IL-10-592 CC genotype could be a useful therapeutic strategy for improving the outcome after allogeneic HSCT.

The Central THαβ Immunity Associated Cytokine: IL-10 Has a Strong Anti-Tumor Ability Toward Established Cancer Models In Vivo and Toward Cancer Cells In Vitro

Immunotherapy is a promising new approach for cancer treatment. In this study, I propose to use the THαβ-mediated immune response for cancer treatment. The THαβ-mediated immune response is activated by IL-10 and IL-15. Thus, I used IL-10 and-15 as therapeutic agents in the 4T1 cell line, which is a mouse cell line of breast cancer, and the NXS2 cell line, which is a mouse cell line of neuroblastoma. Cells from 4T1 and NXS2 were subcutaneously inoculated in wild type BALB/c female mice and AJ mice, respectively, and administered cytokines or an antibody treatment at various dosages. My results showed that IL-10 and IL-15 administration led to reduction in tumor volume and increase in survival. However, traditional TH1 cytokine IFN-γ administration led to increase in tumor volume and decline in survival. Antibody treatment in conjunction with IL-10 was not significantly better than IL-10, due to the expression of GD2 on immune cells. Moreover, an anti-GD2 antibody inhibited the immune cells themselves. Additionally, I found that IL-10 was directly toxic to tumor cells in vitro. Thus, I conclude that the THαβ immunological pathway is a good treatment strategy for cancer.

Tumor microenvironment-associated gene C3 can predict the prognosis of colorectal adenocarcinoma: a study based on TCGA

BACKGROUND

Colorectal cancer is one of the most common malignancies. With continuous exploration of the interaction between tumor cells and the immune system, tumor immunotherapy has become a revolution. However, CRC remains one of the less effective tumors for immunotherapy. The tumor microenvironment plays an important role in tumorigenesis and progression. The aim of this study is to explore tumor microenvironment-related genes that can predict the prognosis of colorectal adenocarcinoma, and also to provide new ideas for the mechanism of tumor development as well as immunotherapy.

METHODS

After estimating Stromalscore and Immunescore of colorectal adenocarcinoma tumor samples according to RNA-Seq expression data downloaded from TCGA, we screened for TME-related differential genes. We filtered prognosis-related core genes by constructing protein-protein interaction networks and making one-factor cox analysis for prognosis. Finally, the relative content of 22 immune cells in tumor tissues was evaluated, and then immune cells associated with core genes were identified.

RESULTS

We screened 773 differential genes related to the TME. Then we identified C3 as a core gene associated with prognosis. Single gene analysis showed that C3 expression was significantly higher in tumor tissues than in normal tissues (p < 0.001). High C3 expression was associated with lower overall survival (p = 0.046). Tumor immune cell analysis showed that mast cells resting, mast cells activated, T cells CD4 memory activated, eosinophils, and macrophages M0 were C3-associated immune cells.

CONCLUSIONS

C3 has potential as a biomarker for colorectal adenocarcinoma and could provide new research ideas for the diagnosis and treatment of colorectal adenocarcinoma, especially for immunotherapy.

Anti-Cancer Effects of Carnosine-A Dipeptide Molecule

Background: Carnosine is a dipeptide molecule (β-alanyl-l-histidine) with anti-inflammatory, antioxidant, anti-glycation, and chelating properties. It is used in exercise physiology as a food supplement to increase performance; however, in vitro evidence suggests that carnosine may exhibit anti-cancer properties. Methods: In this study, we investigated the effect of carnosine on breast, ovarian, colon, and leukemic cancer cell proliferation. We further examined U937 promonocytic, human myeloid leukemia cell phenotype, gene expression, and cytokine secretion to determine if these are linked to carnosine’s anti-proliferative properties. Results: Carnosine (1) inhibits breast, ovarian, colon, and leukemic cancer cell proliferation; (2) upregulates expression of pro-inflammatory molecules; (3) modulates cytokine secretion; and (4) alters U937 differentiation and phenotype. Conclusion: These effects may have implications for a role for carnosine in anti-cancer therapy.

Interleukin-10: A double-edged sword in breast cancer

Breast cancer (BC) is a frequently diagnosed cancer among women worldwide. Currently, BC can be divided into different subgroups according to the presence of the following hormone receptors: estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2. Each of these subgroups has different treatment strategies. However, the presence of new metastatic lesions and patient deterioration suggest resistance to a given treatment. Various lines of evidence had shown that cytokines are one of the important mediators of tumor growth, invasion, metastasis, and treatment resistance. Interleukin-10 (IL-10) is an immunoregulatory cytokine, and acts as a poor prognostic marker in many cancers. The anti-inflammatory IL-10 blocks certain effects of inflammatory cytokines. It also antagonizes the co-stimulatory molecules on the antigen-presenting cells. Here, we review the current knowledge on the function and molecular mechanism of IL-10, and recent findings on how IL-10 contributes to the progression of BC.

Interplay between the Gut Microbiota and Inflammatory Mediators in the Development of Colorectal Cancer

Inflammatory mediators modulate inflammatory pathways during the development of colorectal cancer. Inflammatory mediators secreted by both immune and tumor cells can influence carcinogenesis, progression, and tumor metastasis. The gut microbiota, which colonize the entire intestinal tract, especially the colon, are closely linked to colorectal cancer through an association with inflammatory mediators such as tumor necrosis factor, nuclear factor kappa B, interleukins, and interferons. This association may be a potential therapeutic target, since therapeutic interventions targeting the gut microbiota have been actively investigated in both the laboratory and in clinics and include fecal microbiota transplantation and probiotics.

PARP inhibition and immune modulation: scientific rationale and perspectives for the treatment of gynecologic cancers

Poly[adenosine diphosphate (ADP) ribose]polymerase (PARP) has multifaceted roles in the maintenance of genomic integrity, deoxyribonucleic acid (DNA) repair and replication, and the maintenance of immune-system homeostasis. PARP inhibitors are an attractive oncologic therapy, causing direct cancer cell cytotoxicity by propagating DNA damage and indirectly, by various mechanisms of immunostimulation, including activation of the cGAS/STING pathway, paracrine stimulation of dendritic cells, increased T-cell infiltration, and upregulation of death-ligand receptors to increase susceptibility to natural-killer-cell killing. However, these immunostimulatory effects are counterbalanced by PARPi-mediated upregulation of programmed cell-death-ligand 1 (PD-L1), which leads to immunosuppression. Combining PARP inhibition with immune-checkpoint blockade seeks to exploit the immune stimulatory effects of PARP inhibition while negating the immunosuppressive effects of PD-L1 upregulation.

Biology and therapeutic potential of interleukin-10

The authors review the molecular mechanisms regulating IL-10 production and response and describe classic and novel functions of IL-10 in immune and non-immune cells. They further discuss the therapeutic potential of IL-10 in different diseases and the outstanding questions underlying an effective application of IL-10 in clinical settings.

The cytokine IL-10 is a key anti-inflammatory mediator ensuring protection of a host from over-exuberant responses to pathogens and microbiota, while playing important roles in other settings as sterile wound healing, autoimmunity, cancer, and homeostasis. Here we discuss our current understanding of the regulation of IL-10 production and of the molecular pathways associated with IL-10 responses. In addition to IL-10’s classic inhibitory effects on myeloid cells, we also describe the nonclassic roles attributed to this pleiotropic cytokine, including how IL-10 regulates basic processes of neural and adipose cells and how it promotes CD8 T cell activation, as well as epithelial repair. We further discuss its therapeutic potential in the context of different diseases and the outstanding questions that may help develop an effective application of IL-10 in diverse clinical settings.

Inhibition of Aurora-A Promotes CD8+ T-Cell Infiltration by Mediating IL10 Production in Cancer Cells

Intratumoral tumor-specific activated CD8⁺ T cells with functions in antitumor immune surveillance predict metastasis and clinical outcome in human colorectal cancer. Intratumoral CD8⁺ T cells also affect treatment with immune checkpoint inhibitors. Interestingly, inhibition of Aurora kinase A (Aurora-A) by its selective inhibitor alisertib obviously induced infiltration of CD8⁺ T cells. However, the mechanisms by which inhibition of Aurora-A promotes infiltration of intratumoral CD8⁺ T cells remain unclear. Our recent results demonstrated that conditional deletion of the AURKA gene or blockade of Aurora-A by alisertib slowed tumor growth in association with an increase in the infiltration of intratumoral CD8⁺ T cells as well as the mRNA levels of their IL10 receptor α (IL10Rα). The antitumor effects of targeting Aurora-A were attenuated in the absence of CD8⁺ T cells. In addition, antibody-mediated blockade of IL10Rα dramatically decreased the percentage of intratumoral CD8⁺ T cells. In further experiments, we found that the levels of IL10 were elevated in the serum of azoxymethane/dextran sodium sulfate-treated AURKA^flox/+;VillinCre⁺ mice. Unexpectedly, we found that in addition to Aurora-A's mitotic role, inhibition of Aurora-A elevated IL10 transcription, which in turn increased the IL10Rα mRNA levels in CD8⁺ T cells. Thus, inhibition of Aurora-A could be a useful treatment strategy for recruiting tumor-specific intratumoral CD8⁺ T cells. IMPLICATIONS: Understanding the mechanisms by which inhibition of Aurora-A promotes CD8⁺ T-cell infiltration and activation, as mediated by the IL10 pathway could provide a potential strategy for tumor immunotherapy.

Cytokines that target immune killer cells against tumors

T-cell-stimulating cytokines have shown promise as monotherapies or in combination with other therapeutic modalities for immunotherapy of cancer. However, their efficacy is limited due to their short half-life, pleiotropic roles, and induction of severe toxicity even at therapeutic doses. To overcome these major therapeutic barriers, cytokine-based products are being further developed to improve their therapeutic index. These approaches include manipulating their activity to preferentially bind to effector immune cells rather than immune-suppressive cells, prolonging their half-life in vivo and modifying them to target tumors. This review focuses on IL-2, IL-15, and IL-10, which have potent effects on immune cells that mediate effective antitumor responses. We will summarize the recent progress of these cytokines in both preclinical studies and selective clinical applications and will discuss our perspectives on the development of new strategies to potentiate cytokine-based immunotherapy.

Immunotherapy in breast cancer: Current status and future directions

Breast cancer, one of the leading causes of death in women in the United States, challenges therapeutic success in patients due to tumor heterogeneity, treatment resistance, metastasis and disease recurrence. Knowledge of immune system involvement in normal breast development and breast cancer has led to extensive research into the immune landscape of breast cancer and multiple immunotherapy clinical trials in breast cancer patients. However, poor immunogenicity and T-cell infiltration along with heightened immunosuppression in the tumor microenvironment have been identified as potential challenges to the success of immunotherapy in breast cancer. Oncodrivers, owing to their enhanced expression and stimulation of tumor cell proliferation and survival, present an excellent choice for targeted immunotherapy development in breast cancer. Loss of anti-tumor immune response specific to oncodrivers has been reported in breast cancer patients as well. Dendritic cell vaccines have been tested for their efficacy in generating anti-tumor T-cell response against specific tumor-associated antigens and oncodrivers and have shown improved survival outcome in patients. Here, we review the current status of immunotherapy in breast cancer, focusing on dendritic cell vaccines and their therapeutic application in breast cancer. We further discuss future directions of breast cancer immunotherapy and potential combination strategies involving dendritic cell vaccines and existing chemotherapeutics for improved efficacy and better survival outcome in breast cancer.

Pegylated Interleukin-10: Clinical Development of an Immunoregulatory Cytokine for Use in Cancer Therapeutics

PURPOSE OF REVIEW

Interleukin-10 (IL-10) is a cytokine with anti-inflammatory properties, which induces activation and proliferation of antigen-activated intratumoral CD8+ T cells. This review discusses the evolution of pegylated IL-10 (pegilodecakin) from preclinical investigation through first-in-human studies in oncology.

RECENT FINDINGS

Pegilodecakin was evaluated across multiple advanced solid tumors in a large phase 1/1b trial alone and in combination with chemotherapy or anti-PD-1 antibodies. Pegilodecakin monotherapy had immunologic and clinical activity in renal cell carcinoma (RCC) and uveal melanoma. In combination with anti-PD-1 inhibitors, pegilodecakin increased the responses in RCC and lung cancer with efficacy agnostic to PD-L1 status and tumor mutational burden. Pegilodecakin with FOLFOX had activity in pretreated pancreatic cancer, instructing the ongoing randomized phase III trial of the combination versus FOLFOX. The increased half-life of pegilodecakin enabled compelling preclinical data for IL-10 which has now been confirmed by clinical activity in a variety of cancers. The ability of pegilodecakin to both exert anti-tumor immunity and inhibit tumor-associated inflammation characterizes the uniqueness of this cytokine therapy.

Immune Gene Expression Profile in Hepatocellular Carcinoma and Surrounding Tissue Predicts Time to Tumor Recurrence

BACKGROUND

The antitumor immune response may play a major role in the clinical outcome of hepatocellular carcinoma (HCC). We characterized the liver immune microenvironment by direct hybridization of RNA extracted from HCC and nontumorous tissues.

METHODS

RNA was extracted from frozen liver tissue samples of HCC (T; n = 30) and nontumorous tissues (NT; n = 33) obtained from 38 patients. Matched samples were available for 25 patients. The immune gene expression profile was analyzed with the nCounter GX Human Immunology v2 system (NanoString Technologies), which detects the expression levels of 579 immune response-related genes simultaneously.

RESULTS

Since the immune gene expression profile of T and NT tissues was significantly different, the prognostic relevance of the liver immune microenvironment was evaluated in the T and NT samples separately. Unsupervised clustering detected two main clusters of immune gene expression both in T and in NT liver samples. In both cases, the expression clusters identified groups of patients with a significantly different median time to HCC recurrence (TTR) but similar overall survival. Based on T tissue, two groups with median TTR of 19 and 127 months, respectively, were detected (p < 0.005). Expression of genes related to T-cell activation was associated with longer TTR. The analysis of NT tissue discriminated subsets of patients with median TTR of 22 and 68 months (p < 0.05). In contrast to T tissue, a predominant inflammatory immune environment was associated with shorter TTR.

CONCLUSIONS

Immune gene expression profiles predictive of TTR could be identified both in HCC and in adjacent cirrhotic tissues. Longer TTR was associated with overexpression in T tissue and downregulation in NT tissue of the immune response and of inflammation-related genes.

Tumor Microenvironment: What have we Learned Studying the Immune Response in this Puzzling Battlefield?

Recent developments hallmark the progress in the understanding of tumor immunology and related therapeutic strategies. The administration of interleukin-2 (IL-2) to patients with cancer has shown that immune manipulation can mediate the regression of established cancers. The identification of the genes encoding cancer antigens and the development of means for effectively immunizing against these antigens has opened new avenues for the development of active immunization of patients with cancer. However, an efficient immune response against tumor comprises an intricate molecular network still poorly understood. Only when the code governing immune responsiveness of cancer will be deciphered, new therapeutic strategies could be designed to fit biologically defined mechanisms of immune rejection of cancer.

In this review, we propose that the mechanisms regulating tumor rejection in response to vaccination will be more efficiently identified by following the evolution of treatment induced events within the tumor microenvironment taking advantage of recently developed technological tools. As a model, we will discuss the observed immune response to tumor antigen -specific immunization and its relationship with the systemic administration of IL-2.

Effects of ReadiSorb L-GSH in Altering Granulomatous Responses against Mycobacterium tuberculosis Infection

Mycobacterium tuberculosis (M. tb), a rod-shaped acid-fast bacterium, is the causative agent of tuberculosis (TB). TB remains one of the leading causes of morbidity and mortality worldwide. Additionally, approximately one-third of the world's population has latent tuberculosis infection (LTBI) as a result of the body's primary mechanism of defense against M. tb infection, the formation of a granuloma. A granuloma is the aggregation of immune cells that encapsulate the bacteria to keep them localized to prevent further infection and thus the bacteria become quiescent. However, if an individual becomes immunocompromised, they become more susceptible to M. tb, which may lead to bacterial reactivation and an active infection, because the host is no longer able to generate adequate immune responses. In this study, we examined liposomal glutathione's (L-GSH) effectiveness in promoting the formation of solid, stable granulomas. We assessed this ability by generating in vitro human granulomas constructed from peripheral blood mononuclear cells (PBMCs) that were derived from healthy subjects and testing their granulomatous effector responses against both M. bovis bacille Calmette-Guérin (BCG) and the highly virulent Erdman strain of M. tb. Additionally, we measured the survival and immune characteristics of the Erdman strain of M. tb in THP-1 originated macrophages as well as in vitro granulomas generated from individuals from type 2 diabetes (T2DM). Our results demonstrate that L-GSH treatment can decrease the intracellular survival of both BCG and virulent M. tb, as well as downregulate the levels of overexpressed proinflammatory cytokines delegated from the granulomas derived from not only healthy subjects but also individuals with T2DM.

IL-32 gamma reduces lung tumor development through upregulation of TIMP-3 overexpression and hypomethylation

The low expression of tissue inhibitor of metalloproteinase 3 (TIMP-3) is important in inflammatory responses. Therefore, inhibition of TIMP-3 may promote tumor development. Our study showed that expression of TIMP-3 was elevated in lL-32γ mice lung tissues. In this study, we investigated whether IL-32γ mice inhibited lung tumor development through overexpression of TIMP-3 and its methylation. To explore the possible underlying mechanism, lung cancer cells were transfected with IL-32γ cDNA plasmid. A marked increase in TIMP-3 expression was caused by promoter methylation. Mechanistic studies indicated that TIMP-3 overexpression reduced NF-κB activity, which led to cell growth inhibition in IL-32γ transfected lung cancer cells. We also showed that IL-32γ inhibits expression of DNA (cytosine-5-)-methyltransferase 1 (DNMT1). Moreover, IL-32γ inhibits the binding of DNMT1 to TIMP-3 promoter, but this effect was reversed by the treatment of DNA methyltransferase inhibitor (5-Aza-CdR) and NF-κB inhibitor (PS1145), suggesting that a marked increase in TIMP-3 expression was caused by inhibition of promoter hypermethylation via decreased DNMT1 expression through the NF-κB pathway. In an in vivo carcinogen induced lung tumor model, tumor growth was inhibited in IL-32γ overexpressed mice with elevated TIMP-3 expression and hypomethylation accompanied with reduced NF-κB activity. Moreover, in the lung cancer patient tissue, the expression of IL-32 and TIMP-3 was dramatically decreased at a grade-dependent manner compared to normal lung tissue. In summary, IL-32γ may increase TIMP-3 expression via hypomethylation through inactivation of NF-κB activity, and thereby reduce lung tumor growth.

Cytokine Profiling of Primary Human Macrophages Exposed to Endotoxin-Free Graphene Oxide: Size-Independent NLRP3 Inflammasome Activation

Graphene-based materials including graphene oxide (GO) are envisioned for a variety of biomedical applications. However, there are conflicting results concerning the biocompatibility of these materials. Here, a question is raised whether GO with small or large lateral dimensions triggers cytotoxicity and/or cytokine responses in primary human monocyte-derived macrophages. GO sheets produced under sterile conditions by a modified Hummers' method are found to be taken up by macrophages without signs of cytotoxicity. Then, multiplex arrays are used for profiling of proinflammatory and anti-inflammatory responses. Notably, GO suppresses the lipopolysaccharide (LPS)-triggered induction of several chemokines and cytokines, including the anti-inflammatory cytokine, interleukin-10 (IL-10). No production of proinflammatory TNF-α is observed. However, GO elicits caspase-dependent IL-1 β expression, a hallmark of inflammasome activation, in LPS-primed macrophages. Furthermore, GO-triggered IL-1 β production requires NADPH oxidase-generated reactive oxygen species and cellular uptake of GO and is accompanied by cathepsin B release and K+ efflux. Using THP-1 knockdown cells, a role for the inflammasome sensor, NLRP3, the adaptor protein, ASC, and caspase-1 for GO-induced IL-1β secretion is demonstrated. Finally, these studies show that inflammasome activation is independent of the lateral dimensions of the GO sheets. These studies provide novel insights regarding the immunomodulatory properties of endotoxin-free GO.

Rapamycin Synergizes with Cisplatin in Antiendometrial Cancer Activation by Improving IL-27-Stimulated Cytotoxicity of NK Cells

Natural killer (NK) cell function is critical for controlling initial tumor growth and determining chemosensitivity of the tumor. A synergistic relationship between rapamycin and cisplatin in uterine endometrial cancer (UEC) in vitro has been reported, but the mechanism and the combined therapeutic strategy for endometrial cancer (EC) are still unknown. We found a positive correlation between the level of IL-27 and the differentiated stage of UEC. The increase of IL-27 in uterine endometrial cancer cell (UECC) lines (Ishikawa, RL95-2 and KLE) led to a high cytotoxic activity of NK cells to UECC in the co-culture system. Exposure with rapamycin enhanced the cytotoxicity of NK cells by upregulating the expression of IL-27 in UECC and IL-27 receptors (IL-27Rs: WSX-1 and gp130) on NK cells and further restricted the growth of UEC in Ishikawa-xenografted nude mice. In addition, treatment with rapamycin resulted in an increased autophagy level of UECC, and IL-27 enhanced this ability of rapamycin. Cisplatin-mediated NK cells' cytotoxic activity and anti-UEC activation were independent of IL-27; however, the combination of rapamycin and cisplatin led to a higher cytotoxic activity of NK cells, smaller UEC volume and longer survival rate in vivo. These results suggest that rapamycin and cisplatin synergistically activate the cytotoxicity of NK cells and inhibit the progression of UEC in both an IL-27–dependent and –independent manner. This provides a scientific basis for potential rapamycin-cisplatin combined therapeutic strategies targeted to UEC, especially for the patients with low differentiated stage or abnormally low level of IL-27.

Yoga, Meditation and Mind-Body Health: Increased BDNF, Cortisol Awakening Response, and Altered Inflammatory Marker Expression after a 3-Month Yoga and Meditation Retreat

Thirty-eight individuals (mean age: 34.8 years old) participating in a 3-month yoga and meditation retreat were assessed before and after the intervention for psychometric measures, brain derived neurotrophic factor (BDNF), circadian salivary cortisol levels, and pro- and anti-inflammatory cytokines. Participation in the retreat was found to be associated with decreases in self-reported anxiety and depression as well as increases in mindfulness. As hypothesized, increases in the plasma levels of BDNF and increases in the magnitude of the cortisol awakening response (CAR) were also observed. The normalized change in BDNF levels was inversely correlated with BSI-18 anxiety scores at both the pre-retreat (r = 0.40, p < 0.05) and post-retreat (r = 0.52, p < 0.005) such that those with greater anxiety scores tended to exhibit smaller pre- to post-retreat increases in plasma BDNF levels. In line with a hypothesized decrease in inflammatory processes resulting from the yoga and meditation practices, we found that the plasma level of the anti-inflammatory cytokine Interleukin-10 was increased and the pro-inflammatory cytokine Interleukin-12 was reduced after the retreat. Contrary to our initial hypotheses, plasma levels of other pro-inflammatory cytokines, including Interferon Gamma (IFN-γ), Tumor Necrosis Factor (TNF-α), Interleukin-1β (IL-1β), Interleukin-6 (IL-6), and Interleukin-8 (IL-8) were increased after the retreat. Given evidence from previous studies of the positive effects of meditative practices on mental fitness, autonomic homeostasis and inflammatory status, we hypothesize that these findings are related to the meditative practices throughout the retreat; however, some of the observed changes may also be related to other aspects of the retreat such as physical exercise-related components of the yoga practice and diet. We hypothesize that the patterns of change observed here reflect mind-body integration and well-being. The increased BDNF levels observed is a potential mediator between meditative practices and brain health, the increased CAR is likely a reflection of increased dynamic physiological arousal, and the relationship of the dual enhancement of pro- and anti-inflammatory cytokine changes to healthy immunologic functioning is discussed.

A Listeria-derived polypeptide promotes in vivo activation of NK cells for antitumor therapy

Immunotherapies have shown promise in treatment of cancer, but more potent and targeted therapies are needed. Natural killer (NK) cells are lymphocytes with innate ability to recognize and lyse tumor cells. When activated, they also produce type II interferon (IFNγ) to orchestrate the activity of other immune cells. Strategies to elicit NK cell activation in vivo have potential usefulness in anti-tumor immunotherapies. Here, we report on a strategy to stimulate NK cell activation and anti-tumor activity in mice with established B16.F10 murine melanomas. We and others previously observed that NK cells are rapidly activated during infection by pathogens such as the bacterium Listeria monocytogenes (Lm). A secreted Lm virulence protein, p60, and a fragment of p60 termed L1S were previously shown to stimulate innate immune responses and promote NK cell activation. We purified recombinant L1S and characterized its activity in cell culture studies. Recombinant L1S protein was also observed to promote accumulation and robust NK cell activation in the lungs when given via intratracheal instillation to control and tumor-bearing mice. Importantly, therapeutic administration of a single L1S dose was found to significantly reduce the number and area of "metastatic" tumor nodules on the lungs of mice with established B16.F10 murine melanomas. Depletion studies showed that these antitumor effects were dependent on NK cells and IFNγ. These data provide proof of concept that administration of a single immune-modulating microbial polypeptide can be used to therapeutically boost NK cell in vivo activation and promote anti-tumor responses.

Citrulline and Monocyte-Derived Macrophage Reactivity before Conditioning Predict Acute Graft-versus-Host Disease

During conditioning, intestinal damage induces microbial translocation which primes macrophage reactivity and leads to donor-derived T cell stimulation. Little is known about the role of intestinal health and macrophage reactivity before conditioning in the development of acute graft-versus-host disease (aGVHD) in patients undergoing allogeneic hematopoietic cell transplantation (allo-HCT). We assessed (1) citrulline, a surrogate marker of functional enterocyte mass and (2) circulating monocyte-derived macrophage reactivity, before allo-HCT. Forty-seven consecutive patients were prospectively included. Citrulline levels from blood samples withdrawn 30 days before transplantation were assessed using liquid chromatography combined with mass spectrometry. Monocyte-derived macrophages were isolated and incubated with 5 pathogen-associated molecular patterns: lipopolysaccharide, PamCSK4, flagellin, muramyl dipeptide, and curdlan. Multiplex fluorescent immunoassay on culture supernatant assessed levels of TNF-α, IL-1β, IL-6, and IL-10 in each condition. Citrulline and cytokine levels were analyzed relatively to aGVHD onset within 100 days after transplantation. Citrulline levels were lower in the aGVHD group (n = 20) than in the no-aGVHD group (n = 27) (P = .005). Conversely, IL-6 and IL-10 were greater in aGVHD group, especially after curdlan stimulation (P = .005 and P = .012). Citrulline levels ≤20 µmol/L, IL-6 ≥ 332 pg/mL, and IL-10 ≥ 90 pg/mL were associated with aGVHD development (log-rank test, P = .002, P = .041, and P < .0001, respectively). In multivariate analysis, IL-10 ≥ 90 pg/mL, myeloablative conditioning, and citrulline ≤20 µmol/L remained independent factors of aGVHD development (hazard ratio [HR],  8.18, P = .0003; HR, 4.28, P = .006; and HR, 4.43, P = .01, respectively). Preconditioning citrulline and monocyte-derived macrophage reactivity are objective surrogate markers suitable to identify patients at risk of developing aGVHD. This work highlights the influence of preconditioning status in aGVHD development.

Increased proportion of mature NK cells is associated with successful imatinib discontinuation in chronic myeloid leukemia

Recent studies suggest that a proportion of chronic myeloid leukemia (CML) patients in deep molecular remission can discontinue the tyrosine kinase inhibitor (TKI) treatment without disease relapse. In this multi-center, prospective clinical trial (EURO-SKI, NCT01596114) we analyzed the function and phenotype of T and NK cells and their relation to successful TKI cessation. Lymphocyte subclasses were measured from 100 imatinib-treated patients at baseline and 1 month after the discontinuation, and functional characterization of NK and T cells was done from 45 patients. The proportion of NK cells was associated with the molecular relapse-free survival as patients with higher than median NK-cell percentage at the time of drug discontinuation had better probability to stay in remission. Similar association was not found with T or B cells or their subsets. In non-relapsing patients the NK-cell phenotype was mature, whereas patients with more naïve CD56^bright NK cells had decreased relapse-free survival. In addition, the TNF-α/IFN-γ cytokine secretion by NK cells correlated with the successful drug discontinuation. Our results highlight the role of NK cells in sustaining remission and strengthen the status of CML as an immunogenic tumor warranting novel clinical trials with immunomodulating agents.

PEG-rIL-10 treatment decreases FoxP3(+) Tregs despite upregulation of intratumoral IDO

IL-10 has been classically defined as a broad-spectrum immunosuppressant and is thought to facilitate the development of regulatory CD4(+) T cells. IL-10 is believed to represent one of the major suppressive factors secreted by IDO(+)FoxP3(+)CD4(+) Tregs. Contrary to this view, we have previously reported that PEGylated recombinant IL-10 (PEG-rIL-10) treatment of mice induces potent IFNγ and CD8(+) T-cell-dependent antitumor immunity. This hypothesis is currently being tested in clinical trials and we have reported that treatment of cancer patients with PEG-rHuIL-10 results in inhibition and regression of tumor growth as well as increased serum IFNγ. We have continued to assess PEG-rIL-10's pleiotropic effects and report that treatment of tumor-bearing mice and humans with PEG-rIL-10 increases intratumoral indoleamine 2, 3-dioxygenase (IDO) in an IFNγ-dependent manner. This should result in an increase in Tregs, but paradoxically our data illustrate that PEG-rIL-10 treatment of mice reduces intratumoral FoxP3(+)CD4(+) T cells in an IDO-independent manner. Additional investigation indicates that PEG-rIL-10 inhibits TGFβ/IL-2-dependent in vitro polarization of FoxP3(+)CD4(+) Tregs and potentiates IFNγ(+)T-bet(+)CD4(+) T cells. These data suggest that rather than acting as an immunosuppressant, PEG-rIL-10 may counteract the FoxP3(+)CD4(+) Treg suppressive milieu in tumor-bearing mice and humans, thereby further facilitating PEG-rIL-10's potent antitumor immunity.

Bioinformatics analysis of differentially expressed pathways related to the metastatic characteristics of osteosarcoma

In this study, gene expression data of osteosarcoma (OSA) were analyzed to identify metastasis-related biological pathways. Four gene expression data sets (GSE21257, GSE9508, GSE49003 and GSE66673) were downloaded from Gene Expression Omnibus (GEO). An analysis of differentially expressed genes (DEGs) was performed using the Significance Analysis of Microarray (SAM) method. Gene expression levels were converted into scores of pathways by the Functional Analysis of Individual Microarray Expression (FAIME) algorithm and the differentially expressed pathways (DEPs) were then disclosed by a t-test. The distinguishing and prediction ability of the DEPs for metastatic and non-metastatic OSA was further confirmed using the principal component analysis (PCA) method and 3 gene expression data sets (GSE9508, GSE49003 and GSE66673) based on the support vector machines (SVM) model. A total of 616 downregulated and 681 upregulated genes were identified in the data set, GSE21257. The DEGs could not be used to distinguish metastatic OSA from non-metastatic OSA, as shown by PCA. Thus, an analysis of DEPs was further performed, resulting in 14 DEPs, such as NRAS signaling, Toll-like receptor (TLR) signaling, matrix metalloproteinase (MMP) regulation of cytokines and tumor necrosis factor receptor-associated factor (TRAF)-mediated interferon regulatory factor 7 (IRF7) activation. Cluster analysis indicated that these pathways could be used to distinguish between metastatic OSA from non-metastatic OSA. The prediction accuracy was 91, 66.7 and 87.5% for the data sets, GSE9508, GSE49003 and GSE66673, respectively. The results of PCA further validated that the DEPs could be used to distinguish metastatic OSA from non-metastatic OSA. On the whole, several DEPs were identified in metastatic OSA compared with non-metastatic OSA. Further studies on these pathways and relevant genes may help to enhance our understanding of the molecular mechanisms underlying metastasis and may thus aid in the development of novel therapies.

Interleukin-10 deficiency impairs regulatory T cell-derived neuropilin-1 functions and promotes Th1 and Th17 immunity

Regulatory T cells (Tregs) expand in peripheral lymphoid organs and can produce immunosuppressive cytokines to support tumor growth. IL-10 abrogation efficiently induces Treg formation but dampens tumoral neuropilin-1 (Nrp-1) Treg signaling, which simultaneously augments Th1 and Th17 immunity. These effects are associated with the plasticity and stability of Tregs and effector T cell functions that can limit tumorigenesis. Within the tumor microenvironment, there appears to be a “mutual antagonism” between immunoenhancement and immunosuppression mechanisms, eventually leading to decreased metastasis. In contrast, tumor progression is paralleled by a reduction in Nrp-1-producing Tregs controlled by the IL-10 and TGF-β1 levels. However, Th1, Th17 and Treg immunity is primarily regulated by IL-10 or Nrp-1 and not TGF-β1 except when combined with IL-10. These results emphasize the important implications for the therapeutic use of Tregs. The number of Treg cells must be maintained in a healthy and dynamic homeostatic range to prevent malignant diseases. Moreover, Treg-mediated immunosuppression can be limited by reducing tumor-derived Treg Nrp-1 levels.

Clinical significance of IL-2 and IL-10 gene polymorphisms and serum levels in patients with basal-cell carcinoma

Materials & methods: Polymorphic variants of IL-2 gene (-330 T/G and +166 G/T), IL-10 gene (-1082 G/A and -819 C/T) and serum cytokines concentrations in the group of 179 patients with BCC and 173 controls were analyzed. Results: The presence of the IL-2 -330 GG genotype or IL-10 -1082 GA increased the risk of BCC (OR 3.68) (OR 3.07). IL-10 -1082 AA or GA and IL-2 -330 GG genotype increased the risk of BCC (OR 9.63). IL-2 serum levels were significantly lower (p < 0.0004) in BCC patients while IL-10 concentration was significantly higher (p < 0.00001). Conclusion: The polymorphisms in IL-2 and IL-10 genes may contribute to BCC susceptibility and influence the clinical course of BCC in polish population.

IL-10: Expanding the Immune Oncology Horizon

Recent advances in immunoncology have dramatically changed the treatment options available to cancer patients. However, the fundamental challenges with this therapeutic modality are not new and still persist with the current wave of immunoncology compounds. These challenges are centered on the activation and expansion, induction of intratumoral infiltration and persistence of highly activated, cytotoxic, tumor antigen specific CD8+ T cells. We have investigated the anti-tumor mechanism of action of pegylated recombinant interleukin-10, (PEG-rIL-10) both pre-clinically with murine (PEG-rMuIL-10) and now clinically (AM0010) with human pegylated interleukin-10. The preponderance of data suggest that IL-10's engagement of its receptor on CD8+ T cells enhances their activation status leading to antigen specific expansion. Quantitation of CD8+ T cell tumor infiltration reveals that treatment of both humans and mice with pegylated rIL-10 results in 3-4 fold increases of intratumoral, cytotoxic, CD8+ T cells. In addition, mice cured of their tumors with PEG-rMuIL-10 exhibit long term immunological protection from tumor re-challenge and long term treatment of cancer patients with AM0010 results in the persistence of highly activated CD8+ T cells. Cumulatively, these data suggest the IL-10 represents an emerging therapeutic that specifically addresses the fundamental challenges of the current wave of immunoncology assets.

The Potentiation of IFN-γ and Induction of Cytotoxic Proteins by Pegylated IL-10 in Human CD8 T Cells

Interleukin-10 (IL-10) exerts both immunosuppressive and immunostimulatory effects. While the immunosuppressive effects are widely known, it has only been recently reported that pegylated recombinant human IL-10 (PEG-rHuIL-10) elicits potent interferon-γ (IFN-γ) and CD8 T-cell-dependent antitumor effects in murine tumor models. In this study, we show that PEG-rHuIL-10 exerts immune inhibitory effects on human peripheral blood mononuclear cell (PBMC) bulk cultures and stimulatory effects in CD8 T cells within the same culture. Also, in isolated CD8 T cells, PEG-rHuIL-10 potentiates prototypic Tc1 cytokine IFN-γ expression and induces perforin and granzyme B secretion. IFN-γ and granzyme B secretion is dependent on T-cell receptor ligation and is therefore not indiscriminately released by PEG-rHuIL-10 treatment. STAT3, NF-κB, AP1, and MEK inhibition blocks IFN-γ potentiation, while perforin induction is impeded by AP1 inhibition, and granzyme B induction is blocked by both AP1 and MEK inhibition. These results extend previous pegylated IL-10 preclinical findings to human CD8 T cells and implicate a strong degree of translation for pegylated IL-10 use in cancer therapy.

Vaccine-induced but not tumor-derived Interleukin-10 dictates the efficacy of Interleukin-10 blockade in therapeutic vaccination

Blocking antibodies against immunosuppressive molecules have shown promising results in cancer patients. However, there are not enough data to define those conditions dictating treatment efficacy. In this scenario, IL-10 is a cytokine with controversial effects on tumor growth. Thus, our aim was to characterize in which setting IL-10 blockade may potentiate the beneficial effects of a therapeutic vaccine In the IL-10-expressing B16-OVA and TC-1 P3 (A15) tumor models, therapeutic vaccination with tumor antigens plus the TLR7 ligand Imiquimod increased IL-10 production. Although blockade of IL-10 signal with anti-IL-10R antibodies did not inhibit tumor growth, when combined with vaccination it enhanced tumor rejection, associated with stronger innate and adaptive immune responses. Interestingly, a similar enhancement on immune responses was observed after simultaneous vaccination and IL-10 blockade in naive mice. However, when using vaccines containing as adjuvants the TLR3 ligand poly(I:C) or anti-CD40 agonistic antibodies, despite tumor IL-10 expression, anti-IL-10R antibodies did not provide any beneficial effect on tumor growth and antitumor immune responses. Of note, as opposed to Imiquimod, vaccination with this type of adjuvants did not induce IL-10 and correlated with a lack of in vitro IL-10 production by dendritic cells (DC). Finally, in B16-OVA-bearing mice, blockade of IL-10 during therapeutic vaccination with a multiple adjuvant combination (MAC) with potent immunostimulatory properties but still inducing IL-10 led to superior antitumor immunity and complete tumor rejection. These results suggest that for therapeutic antitumor vaccination, blockade of vaccine-induced IL-10 is more relevant than tumor-associated IL-10.

Immunosuppressive Mechanisms of Malignant Gliomas: Parallels at Non-CNS Sites

The central nervous system (CNS) possesses powerful local and global immunosuppressive capabilities that modulate unwanted inflammatory reactions in nervous tissue. These same immune-modulatory mechanisms are also co-opted by malignant brain tumors and pose a formidable challenge to brain tumor immunotherapy. Routes by which malignant gliomas coordinate immunosuppression include the mechanical and functional barriers of the CNS; immunosuppressive cytokines and catabolites; immune checkpoint molecules; tumor-infiltrating immune cells; and suppressor immune cells. The challenges to overcoming tumor-induced immunosuppression, however, are not unique to the brain, and several analogous immunosuppressive mechanisms also exist for primary tumors outside of the CNS. Ultimately, the immune responses in the CNS are linked and complementary to immune processes in the periphery, and advances in tumor immunotherapy in peripheral sites may therefore illuminate novel approaches to brain tumor immunotherapy, and vice versa.

IL-10 enhances CTL-mediated tumor rejection by inhibiting highly suppressive CD4+ T cells and promoting CTL persistence in a murine model of plasmacytoma

Interleukin-10 (IL-10) is a potent anti-inflammatory cytokine that regulates immune responses. IL-10 has also been shown to enhance antitumor CD8⁺ T-cell responses in tumor models although the underlying mechanisms are not fully understood. In this study, we used a series of genetic mouse models and the mouse plasmacytoma J558 model to investigate this issue. J558 tumors grew significantly faster in IL-10^-/- mice than in wild type (WT) mice, but similarly in IL-10 ^-/- Rag2 ^-/- and Rag2 ^-/- mice. Tumors from IL-10 ^-/- mice contained fewer IFN-γ-producing CD8⁺ and CD4⁺ T cells than tumors from WT mice. Strikingly, depletion of total CD4⁺ T cells, but not CD25⁺ cells, resulted in tumor eradication in IL-10 ^-/- mice. Adoptive transfer studies revealed that CD4⁺ T cells from IL-10 ^-/- mice exhibited more potent suppression of cytotoxic T lymphocyte (CTL)-mediated tumor rejection than their WT counterparts, and IL-10-deficient tumor-infiltrating CD4⁺ T cells expressed higher levels of PD-L1 and CTLA-4 inhibitory molecules. Although IL-10-deficient CD8⁺ T cells are not defective in activation and initial rejection of tumors, adoptive transfer studies using IL-10-deficient P1CTL transgenic T cells that recognize the tumor rejection antigen P1A reveal that IL-10 is required for long-term persistence of CTLs and control of tumor growth. Thus, we have found that IL-10 enhances antitumor CTL responses by inhibiting highly suppressive CD4⁺ T cells and promoting CTL persistence. These data have important implications for the design of immunotherapy for human cancer.

T-cell Expression of IL10 Is Essential for Tumor Immune Surveillance in the Small Intestine

IL10 is attributed with immune-suppressive and anti-inflammatory properties, which could promote or suppress cancer in the gastrointestinal tract. Loss of IL10 exacerbates colonic inflammation, leading to colitis and cancer. Consistent with this, transfer of IL10-competent regulatory T cells (Treg) into mice with colitis or hereditary polyposis protects against disease, while IL10-deficient mice are predisposed to polyposis with increased colon polyp load. Little is known about the protective or pathogenic function of IL10 in cancers of the small intestine. We found CD4(+) T cells and CD4(+) Foxp3(+) Tregs to be the major sources of IL10 in the small intestine and responsible for the increase in IL10 during polyposis in the APC(Δ468) mouse model of hereditary polyposis. Targeted ablation of IL10 in T cells caused severe IL10 deficiency and delayed polyp growth. However, these polyps progressively lost cytotoxic activity and eventually progressed to cancer. Several observations suggested that the effect was due to the loss of IFNγ-dependent immune surveillance. IL10-incompetent CD4(+) T cells failed to secrete IFNγ when stimulated with polyp antigens and were inefficient in T-helper-1 (TH1) commitment. By contrast, the TH17 commitment was unaffected. These findings were validated using mice whose T cells overexpress IL10. In these mice, we observed high intra-polyp cytotoxic activity and attenuation of polyposis. Thus, expression of IL10 by T cells is protective and required for immune surveillance in the small intestine.

Osteopontin (OPN) isoforms, diabetes, obesity, and cancer; what is one got to do with the other? A new role for OPN

Alternative splicing of osteopontin (OPN) produces three isoforms: OPNa, OPNb, and OPNc. The aims of this study were to examine the expression profile of OPN isoforms in sera from patients with pancreatic lesions and to determine their correlation with the presence of comorbid systemic inflammatory conditions, such as diabetes and/or obesity. Sera from 90 patients undergoing pancreatic surgery and 29 healthy volunteers were analyzed. Seventeen patients were diabetics, 17 were obese, and 6 had both diabetes and obesity. In patients with pancreatic lesions, OPNb was expressed in 48% of the patients' sera, OPNc in 34%, and both in 5%. The presence of diabetes and/or obesity was associated with complete disappearance of OPNb and expression of only OPNc. OPNc presence was significantly associated with diabetes and obesity (OR = 7.06 [95% CI 1.97-23.3]; p = 0.003). No OPNb or OPNc was detected in the normal sera. Overexpression of OPNb and OPNc isoforms in PDA cells significantly (p < 0.05) increased their activity in soft-agar colony formation and wound healing assays, induced the transcription of interleukin (IL)-6, and reduced tumor necrosis factor alpha (TNF-α), interferon gamma (IFN-γ), and IL-10. Our data show for the first time the significant association between serum OPNc and diabetes and/or obesity. Unraveling the functional role of OPN isoforms in systemic inflammation is essential to understanding their significance as therapeutic targets in diabetes and obesity, and during metastasis development in PDA.

NKT cells act through third party bone marrow-derived cells to suppress NK cell activity in the liver and exacerbate hepatic melanoma metastases

Uveal melanoma (UM) is the most common intraocular tumor in adults and liver metastasis is the leading cause of death in UM patients. We have previously shown that NKT cell-deficient mice develop significantly fewer liver metastases from intraocular melanomas than do wild-type (WT) mice. Here, we examine the interplay between liver NKT cells and NK cells in resistance to liver metastases from intraocular melanomas. NKT cell-deficient CD1d(-/-) mice and WT C57BL/6 mice treated with anti-CD1d antibody developed significantly fewer liver metastases than WT mice following either intraocular or intrasplenic injection of B16LS9 melanoma cells. The increased number of metastases in WT mice was associated with reduced liver NK cytotoxicity and decreased production of IFN-γ. However, liver NK cell-mediated cytotoxic activity was identical in non-tumor bearing NKT cell-deficient mice and WT mice, indicating that liver metastases were crucial for the suppression of liver NK cells. Depressed liver NK cytotoxicity in WT mice was associated with production of IL-10 by bone marrow-derived liver cells that were neither Kupffer cells nor myeloid-derived suppressor cells and by increased IL-10 receptor expression on liver NK cells. IL-10(-/-) mice had significantly fewer liver metastases than WT mice, but were not significantly different from NKT cell-deficient mice. Thus, development of melanoma liver metastases is associated with upregulation of IL-10 in the liver and an elevated expression of IL-10 receptor on liver NK cells. This impairment of liver NK activity is NKT cell-dependent and only occurs in hosts with melanoma liver metastases.

Manipulating IL-10 signalling blockade for better immunotherapy

Interleukin 10 is a cytokine with the ability to reduce or terminate inflammation. Chronic viral infection, such as infection of chronic hepatitis B, hepatitis C and HIV, has increased levels of interleukin 10 in peripheral blood. Serum IL-10 levels are also high in certain cancers. Blocking IL-10 signalling at the time of immunisation clears chronic viral infection and prevents tumour growth in animal models. We review recent advances in this area, with the emphasis on potential use of this novel strategy to treat chronic viral infection and cancer in human.