IL-17A weakens the antitumor immuity by inhibiting apoptosis of MDSCs in Lewis lung carcinoma bearing mice

Pancreatic stellate cells and the interleukin family: Linking fibrosis and immunity to pancreatic ductal adenocarcinoma (Review)

Pancreatic ductal adenocarcinoma (PDAC) is an extremely aggressive form of cancer with a low survival rate. A successful treatment strategy should not be limited to targeting cancer cells alone, but should adopt a more comprehensive approach, taking into account other influential factors. These include the extracellular matrix (ECM) and immune microenvironment, both of which are integral components of the tumor microenvironment. The present review describes the roles of pancreatic stellate cells, differentiated cancer‑associated fibroblasts and the interleukin family, either independently or in combination, in the progression of precursor lesions in pancreatic intraepithelial neoplasia and PDAC. These elements contribute to ECM deposition and immunosuppression in PDAC. Therapeutic strategies that integrate interleukin and/or stromal blockade for PDAC immunomodulation and fibrogenesis have yielded inconsistent results. A deeper comprehension of the intricate interplay between fibrosis, and immune responses could pave the way for more effective treatment targets, by elucidating the mechanisms and causes of ECM fibrosis during PDAC progression.

The impact of IL-10 and IL-17 on myeloid-derived suppressor cells in vitro and in vivo in a murine model of asthma

Myeloid-derived suppressor cells (MDSCs) hold promise for clinical applications due to their immunosuppressive properties, particularly in the context of inflammation. In the present study, the number and immunosuppressive activity of MDSCs isolated from naïve Il10-/-, Il17-/-, and WT mice as control, as well as from house dust mite extract (HDM)-induced asthmatic Il10-/- and Il17-/- mice, were investigated. IL-10 deficiency increased the number of polymorphonuclear (PMN)-MDSCs in the lung, spleen, and bone marrow, without concurrent impairment of their suppressive activity in vitro. In the asthma model, the IL-17 knockout was concomitant with a lower number and activity of monocytic (M)-MDSCs and an altered inflammatory reaction with impaired lung function. Additionally, we found a higher baseline inflammation of the Il17-/- mice in the lung, manifested in increased airway resistance. We conclude that the impact of IL-10 and IL-17 deficiency on MDSCs differs in the context of inflammation. Accordingly, the in vitro experiments demonstrated an increased number of PMN-MDSCs across tissues in Il10-/- mice, which indicates that IL-10 might serve a pivotal role in preserving immune homeostasis under physiological circumstances. In the context of HDM-induced airway inflammation, IL-17 was found to be an important player in the suppression of pulmonary inflammation and regulation of M-MDSCs.

IL-17 in the Pathogenesis of Disease: Good Intentions Gone Awry

The IL-17 family is an evolutionarily old cytokine family consisting of six members (IL-17A through IL-17F). IL-17 family cytokines signal through heterodimeric receptors that include the shared IL-17RA subunit, which is widely expressed throughout the body on both hematopoietic and nonhematopoietic cells. The founding family member, IL-17A, is usually referred to as IL-17 and has received the most attention for proinflammatory roles in autoimmune diseases like psoriasis. However, IL-17 is associated with a wide array of diseases with perhaps surprisingly variable pathologies. This review focuses on recent advances in the roles of IL-17 during health and in disease pathogenesis. To decipher the functions of IL-17 in diverse disease processes it is useful to first consider the physiological functions that IL-17 contributes to health. We then discuss how these beneficial functions can be diverted toward pathogenic amplification of deleterious pathways driving chronic disease.

The interplay of interleukin-17A and breast cancer tumor microenvironment as a novel immunotherapeutic approach to increase tumor immunogenicity

Based on its known role in mediating tumor progression and the correlation with poor response to chemotherapy, we hypothesized that blocking interleukin-17A (IL-17A) by anti-IL-17 monoclonal antibodies might have the ability to suppress programmed death-ligand-1 (PD-L1) and to modulate the expression and function of myeloid-derived suppressor cells (MDSCs) in BC microenvironment. We also compared the apoptotic activity of anti-IL-17 with those acquired from our previous work on monoclonal antibodies against IL-6. The influence of anti-IL-17 was investigated in two doses on localized freshly resected tissues from 50 patients with BC. Results revealed increased IL-17A in BC tumor tissues versus surrounding tissues. Additionally, PD-L1 expression was inhibited in cultures treated with both doses of anti-IL-17. Frequencies of MDSCs were reduced in those cultures with anti-IL-17 with reduced suppressive activity. The induced apoptosis in the tumor cells was significantly increased. Anti-IL-17 antibodies effect was related to late stages, vascular metastasis, and hormonal status. Results of the current work suggest a promising role for anti-IL-17 monoclonal antibodies in enhancement of anti-tumor immunological activity in BC, potentially involving suppression of immune checkpoint PD-L1 and MDSCs inhibition with a marked response in aggressive disease.

In Vivo Photodynamic Therapy With a Lipophilic Zinc(II) Phthalocyanine Inhibits Colorectal Cancer and Induces a Th1/CD8 Antitumor Immune Response

BACKGROUND AND OBJECTIVES

Photodynamic therapy (PDT) is an antitumor procedure clinically approved for the treatment of different cancer types. Despite strong efforts and promising results in this field, PDT has not yet been approved by any regulatory authority for the treatment of colorectal cancer, one of the most prevalent gastrointestinal tumors. In the search of novel therapeutic strategies, we examined the in vivo effect of PDT with a lipophilic phthalocyanine (Pc9) encapsulated into polymeric poloxamine micelles (T1107) in a murine colon carcinoma model.

STUDY DESIGN/MATERIALS AND METHODS

In vivo assays were performed with BALB/c mice challenged with CT26 cells. Pc9 tumor uptake was evaluated with an in vivo imaging system. Immunofluorescence, western blot, and flow cytometry assays were carried out to characterize the activation of apoptosis and an antitumor immune response.

RESULTS

Pc9-T1107 effectively delayed tumor growth and prolonged mice survival, without generating systemic or tissue-specific toxicity. The induction of an apoptotic response was characterized by a decrease in the expression levels of Bcl-X_L , Bcl-2, procaspase 3, full length Bid, a significant increment in the amount of active caspase-3 and the detection of PARP-1 cleavage. Infiltration of CD8⁺ CD107a⁺ T cells and higher levels of interferon-γ and tumor necrosis factor-α were also found in PDT-treated tumors.

CONCLUSIONS

Pc9-T1107 PDT treatment reduced tumor growth, inducing an apoptotic cell death and activating an immune response. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.

T-Cell Proapoptotic and Antifibrotic Activity Against Autologous Skin Fibroblasts in vitro Is Associated With IL-17A Axis Upregulation in Systemic Sclerosis

Background: Systemic sclerosis (SSc) T cells can induce apoptosis of autologous skin fibroblasts in vitro. Th17 cells have been reported to increase in SSc patients, and interleukin-17A (IL-17A) has a profibrotic function. We used a system based on T-cell-autologous fibroblast co-cultures to further investigate a possible role of IL-17A in SSc.

Methods: T cells from diffuse SSc patients were co-cultured with autologous skin fibroblasts. IL17A mRNA was assessed by real-time PCR in co-cultured and control T cells, while IL17RA, CXCL1, CCL2, CCL3, COL1A1, COL3A1, CTGF, TGFBR2, and SMAD3 mRNAs were assessed in co-cultured and control fibroblasts. In subset experiments, co-cultures and control cells were treated with either IL-17A or IL-17A plus anti-IL17 receptor monoclonal antibody (α-IL-17RA mAb). Chemokine and procollagen type I (PCI) production was further investigated at the protein level in cell culture supernatants by multiple suspension immunoassay and sandwich ELISA, respectively. Co-cultured and control fibroblasts were also stained with Annexin V and analyzed by flow cytometry.

Results: T cell–fibroblast co-cultures overexpressed IL17A and IL17RA. Furthermore, co-cultured fibroblasts upregulated IL-17A targets CXCL1, CCL2, and CCL3, while COL1A1, COL3A1, CTGF, and two key effectors of the TGF-β signaling, TGFBR2 and SMAD3, were found downregulated. Consistently, chemokine concentrations were increased in co-culture supernatants, while PCI levels were reduced, especially after stimulation with ectopic IL-17A. Finally, simultaneous α-IL-17RA mAb treatment restored PCI levels and reduced fibroblast apoptosis in IL-17A-stimulated co-cultures.

Conclusion: These data suggest that IL-17A upregulation might play a role in modulating T cell-mediated antifibrotic and proapoptotic effects in co-cultured autologous skin fibroblasts.

Gemcitabine nanoparticles promote antitumor immunity against melanoma

Myeloid-derived suppressor cells (MDSCs) promote tumor-mediated immunosuppression and cancer progression. Gemcitabine (Gem) is a MDSC-depleting chemotherapeutic agent; however, its clinical use is hampered by its drug resistance and inefficient in vivo delivery. Here we describe a strategy to formulate a Gem analogue gemcitabine monophosphate (GMP) into a lipid-coated calcium phosphate (LCP) nanoparticle, and investigate its antitumor immunity and therapeutic effects after systemic administrations. In the syngeneic mouse model of B16F10 melanoma, compared with free Gem, the LCP-formulated GMP (LCP-GMP) significantly induced apoptosis and reduced immunosuppression in the tumor microenvironment (TME). LCP-GMP effectively depleted MDSCs and regulatory T cells, and skewed macrophage polarization towards the antitumor M1 phenotype in the TME, leading to enhanced CD8⁺ T-cell immune response and profound tumor growth inhibition. Thus, engineering the in vivo delivery of MDSC-depleting agents using nanotechnology could substantially modulate immunosuppressive TME and boost T-cell immune response for enhanced antitumor efficacy.

Untargeted metabolomics profiles delineate metabolic alterations in mouse plasma during lung carcinoma development using UPLC-QTOF/MS in MSE mode

In this work, an untargeted metabolomic method based on ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF/MS) in MSE (E represents collision energy) mode was exploited to determine the dynamic metabolic alterations in the plasma of male C57BL/6 mice during the onset and development of lung carcinoma. Plasma samples were collected from control and model mice (male C57BL/6 mice experimentally inoculated with the Lewis lung carcinoma cells) at 7 and 14 days post-inoculation (DPI). As a result, 15 dysregulated metabolites, including cholesterol sulphate, tiglylcarnitine, 1-palmitoylglycerophosphoinositol, 2-stearoylglycerophosphoinositol, stearoylcarnitine, PC(20:2(11Z,14Z)/16:0), PC(22:4(7Z,10Z,13Z,16Z)/14:0), PC(22:5(7Z,10Z,13Z,16Z,19Z)/14:0), PC(22:6(4Z,7Z,10Z,13Z,16Z,19Z)/16:0), 12,20-Dioxo-leukotriene B4, sphingosine 1-phosphate(d19:1-P), sphingomyelin(d18:0/16:1(9Z)), lysoPC(16:0), lysoPC(18:0) and lysoPC(20:4(5Z,8Z,11Z,14Z)), were identified in the plasma of model mice with xenografts at both 7 and 14 DPI. All the altered metabolites associated with the onset and development of lung carcinoma were involved in the metabolism of glycerophospholipid, fatty acid, sphingolipid and arachidonic acid. The feasible utility of these endogenous biomarkers as potential diagnostic indicators was validated through receiver operating characteristic curve analysis. Collectively, these findings provide a systematic view of metabolic changes linked to the onset and development of lung carcinoma.

MiR-486 promotes proliferation and suppresses apoptosis in myeloid cells by targeting Cebpa in vitro

The monocytic MDSC (M‐MDSC) is one of the major types of MDSCs, which play important roles in suppression of antitumor immunity. However, the mechanisms underlying how M‐MDSCs so heavily accumulate in patients with cancer are still poorly understood. The purpose of this study was to identify miRNAs that regulate the proliferation and differentiation of M‐MDSCs. Microarray analysis was performed to identify differentially expressed miRNAs between tumor‐induced M‐MDSCs (TM‐MDSCs) and their counterparts from tumor‐free mice. The miRNAs and their target genes that regulate the proliferation and differentiation of myeloid cells were predicted by bioinformatics analysis and validated by RT‐qPCR. Luciferase reporter assays were used to analyze the relationships between miRNAs and target genes. Overexpression of candidate miRNAs and target genes in myeloid cells was conducted to verify their functions in cell proliferation, differentiation, and apoptosis. Our data showed that miR‐486 was overexpressed in TM‐MDSCs. Cebpa was predicted to be one of the target genes of miR‐486 that regulates the proliferation of myeloid cells. Expression of Cebpa was inversely correlated with miR‐486 in TM‐MDSCs, and we found that overexpression of miR‐486 suppressed the expression of Cebpa in both 293T cells determined by luciferase reporter assays and in myeloid cells determined by RT‐qPCR. Overexpression of miR‐486 promoted proliferation and suppressed apoptosis in myeloid cells, as opposed to overexpression of Cebpa, which promoted the opposing phenotype. Overexpression of either miR‐486 or Cebpa inhibited differentiation of myeloid cells. This study indicates that miR‐486 promotes proliferation and suppresses apoptosis in myeloid cells by targeting Cebpa in vitro, suggesting that miR‐486 and Cebpa might be involved in the expansion of TM‐MDSCs in tumor‐bearing mice.

Interleukin 17 and peripheral IL-17-expressing T cells are negatively correlated with the overall survival of head and neck cancer patients

The presence and clinical significance of interleukin (IL)-17 and IL-17-expressing cells have recently been studied in several types of cancer, but their correlation to tumor development remains controversial. Additionally, the contribution of peripheral IL-17-expressing cells to head and neck cancer (HNC) progression is still poorly understood. We collected peripheral blood from healthy donors and HNC patients to isolate PBMCs. The percentages of IL-17-expressing cells and the production of inflammatory cytokines in PBMCs were measured to determine their association with clinical outcomes and overall survival in HNC. We evaluated the effect and potential mechanism of IL-17 on human oral squamous carcinomas in vitro using exogenous IL-17 stimulation. In comparison to healthy donors, the PBMCs of HNC patients have a significant accumulation of IL-17-expressing T cells and their frequencies were positively correlated with the disease stage. A significantly higher production of PBMC IL-17, TGF-β and IL-21 and plasma VEGF-A were found in HNC patients. Importantly, the 5-years overall survival of HNC patients with a higher percentage of IL-17-expressing cells is significantly decreased. Furthermore, the addition of IL-17 appeared to promote human oral squamous carcinoma cell proliferation via the production of IL-6 and VEGF-A. Our findings suggest that IL-17 has the potential to mediate pro-tumor immunity in the HNC tumor microenvironment. Enhanced IL-17-expressing cells, including Th17 and Tc17 cells, in the peripheral blood could be a significant predictor of a poor prognosis for HNC patients.