Lewis Lung Cancer Cells Promote SIGNR1(CD209b)-Mediated Macrophages Polarization Induced by IL-4 to Facilitate Immune Evasion

Lung-resident alveolar macrophages regulate the timing of breast cancer metastasis

Breast disseminated cancer cells (DCCs) can remain dormant in the lungs for extended periods, but the mechanisms limiting their expansion are not well understood. Research indicates that tissue-resident alveolar macrophages suppress breast cancer metastasis in lung alveoli by inducing dormancy. Through ligand-receptor mapping and intravital imaging, it was found that alveolar macrophages express transforming growth factor (TGF)-β2. This expression, along with persistent macrophage-cancer cell interactions via the TGF-βRIII receptor, maintains cancer cells in a dormant state. Depleting alveolar macrophages or losing the TGF-β2 receptor in cancer cells triggers metastatic awakening. Aggressive breast cancer cells are either suppressed by alveolar macrophages or evade this suppression by avoiding interaction and downregulating the TGF-β2 receptor. Restoring TGF-βRIII in aggressive cells reinstates TGF-β2-mediated macrophage growth suppression. Thus, alveolar macrophages act as a metastasis immune barrier, and downregulation of TGF-β2 signaling allows cancer cells to overcome macrophage-mediated growth suppression.

Single cell transcriptomics reveals dysregulated immnue homeostasis in different stages in HPV-induced cutaneous squamous cell carcinoma

In order to explore the huge impact of impaired immnue homeostasis on the occurrence and development of cutaneous squamous cell carcinoma (cSCC), and investigate characterization of the cellular components and their changes which is crucial to understanding the pathologic process of HPV-induced cSCC, we diagnosed and followed up on a very rare HPV-induced cSCC patient who progressed at a very fast rate and transferred to death quickly. We performed single-cell RNA sequencing (scRNA-seq) of 11 379 cells from the skin tissues of this patient with four different skin statuses after HPV infection. Immunofluorescence experiments were used for validation. scRNA-seq identified that CD52+ HLA-DOA- macrophages only existed in paracancerous cutaneous squamous cell carcinoma (pc-cSCC) and cSCC tissue. Besides, immune cells including CD8+ exhausted T cells and CD4+ regulatory T cells as well as matrix cells like MMP1+, and MMP11+ fibroblasts were gradually increased. Meanwhile, COMP+ ASPN+ fibroblasts gradually decreased. Cell interaction analysis revealed enhancement in interactions between monocytes/macrophages, fibroblasts and tumour-specific keratinocytes. scRNA-seq was performed in HPV-induced cSCC for the first time, to explore the correlation between infection and tumour. It is the first time to study the development of tumours from different stages of infection in HPV-induced cSCC. In this study, the tumour itself and the tumour microenvironment were both analysed and explored. And it was validated in clinical samples from different patients. Our findings reveal the dynamic immnue homeostasis from normal skin to cSCC tissue, this alteration might drive HPV-induced cSCC.

RSK4 promotes the macrophage recruitment and M2 polarization in esophageal squamous cell carcinoma

High infiltration of tumor-associated macrophages (TAMs) participates in host immunity and tumor progression in patients with esophageal squamous cell carcinoma (ESCC). Ribosomal s6 kinase 4 (RSK4) has been shown to be aberrantly overexpressed in ESCC. The role of RSK4 in cytokine secretion and its impact on macrophage recruitment and M2 polarization remains unclear. Therefore, a thorough understanding of RSK4 is needed to expand our knowledge of its therapeutic potential. Herein, RSK4 expression in human ESCC tissues and a xenograft mouse model was positively correlated with high infiltration of M0 and M2 macrophages which is positively associated with unfavorable overall survival outcomes and treatment resistance in patients with ESCC. In vitro experiments revealed that RSK4 derived from ESCC cells promoted macrophage recruitment and M2 polarization by enhancingsoluble intercellular adhesion molecule-1 (sICAM-1) secretion via direct and indirect STAT3 phosphorylation. Furthermore, RSK4-induced macrophages enhanced tumor proliferation, migration, and invasion by secreting C-C motif chemokine ligand 22 (CCL22). We further showed that patients with elevated CD68 and CD206 expression had unfavorable overall survival. Collectively, these results demonstrate that RSK4 promotes the macrophage recruitment and M2 polarization by regulating the STAT3/ICAM-1 axis in ESCC, influencing tumor progression primarily in a CCL22-dependent manner. These data also offer valuable insights for developing novel agents for the treatment of ESCC.

Role of Natural Antioxidants in Cancer

The oxidative stress defined as an event caused by an imbalance between production and accumulation of reactive oxygen species (ROS), which lead to a damage in the structure of proteins, lipids, and DNA. Therefore, the production of ROS may alter the normal physiological process by provoking damage to multiple cellular organelles and processes. Oxidative stress has been linked to heart disease, cancer, respiratory diseases, immune deficiency, stroke, Parkinson's disease, and other inflammatory or ischemic conditions. Antioxidants are substances that can prevent or slow damage to cells and tissues caused by ROS, unstable molecules that the body produces as a reaction to environmental and other pressures. The β-carotene, catechins, flavonoids, polyphenols, lycopene, lutein, selenium, vitamins A, C, D, E, and zeaxanthin are all common types of antioxidants and found in plant-based foods, especially fruits and vegetables. Each antioxidant has its own role and can interact with others to process and remove free radicals efficiently. Several studies have been conducted to investigate whether the use of dietary antioxidant supplements is associated with decreased risks of developing cancer in humans, mixed results were reported. For instance, daily use of supplement such as vitamin c, vitamin E, β-Carotene, and minerals such as selenium and zinc have shown its effectiveness by reducing the risk of developing prostate cancer among men and skin cancer among women.

Sialylated IVIg binding to DC-SIGN+ Hofbauer cells induces immune tolerance through the caveolin-1/NF-kB pathway and IL-10 secretion

Although the use of IVIg has increased in various immune-driven diseases and even in pregnancy, the exact action mechanisms of IVIg are not fully understood. Dendritic cell-specific intercellular adhesion molecule-3 grabbing non-integrin (DC-SIGN) is a known receptor for α-2,6-sialylated IgG (sIVIg), which is responsible for the anti-inflammatory effect of IVIg. DC-SIGN is expressed on Hofbauer cells (HBCs) of the fetal villi of the placenta which act as an innate immune modulator at the maternal-fetal interface. Preeclampsia is a major complication in pregnancy and is related to IL-10, a cytokine with an important role in immune tolerance. DC-SIGN interaction with sIVIg in HBCs promoted IL-10 secretion through the activation of the caveolin-1/NF-κB pathway, especially in plasma lipid rafts. Consistent results were obtained for HBCs from patients with preeclampsia. Collectively, the stimulation of DC-SIGN⁺ HBCs with sIVIg enhanced immune tolerance in the feto-maternal environment, suggesting the therapeutic application of sIVIg to prevent preeclampsia.

Blockade of STAT3/IL-4 overcomes EGFR T790M-cis-L792F-induced resistance to osimertinib via suppressing M2 macrophages polarization

BACKGROUND

The mechanism of missense alteration at EGFR L792F in patients with non-small cell lung cancer resistant to osimertinib has not been sufficiently clarified. We aimed to explore the critical molecular events and coping strategies in osimertinib resistance due to acquired L792F mutation.

METHODS

Circulating tumor DNA-based sequencing data of 1153 patients with osimertinib resistance were collected to illustrate the prevalence of EGFR L792F mutation. Sensitivity to osimertinib was tested with constructed EGFR 19Del/T790M-cis-L792F cell lines in vitro and in vivo. The correlation and linked pathways between M2 macrophage polarization and EGFR L792Fcis-induced osimertinib resistance were investigated. Possible interventions to suppress osimertinib resistance by targeting IL-4 or STAT3 were explored.

FINDINGS

The concomitant EGFR L792F was identified as an independent mutation following the acquisition of T790M after osimertinib resistance, in that 5 of the 946 patients with osimertinib resistance harbored EGFR T790M-cis-L792F mutation. Transfected EGFR 19Del/T790M-cis-L792F in cell lines had decreased sensitivity to osimertinib and enhanced infiltrating macrophage with M2 polarization. Silico analyses confirmed the role of M2 polarization in osimertinib resistance induced by EGFR T790M-cis-L792F mutation. EGFR T790M-cis-L792F mutation upregulated phosphorylation of STAT3 Tyr705 and promoted its specific binding to IL4 promoter, enhancing IL-4 expression and secretion and inducing macrophage M2 polarization. Furthermore, blockade of STAT3/IL-4 (SH-4-54 or dupilumab) suppressed macrophage M2 polarization and regressed tumor sensitivity to osimertinib.

INTERPRETATION

Our results proved that targeting EGFR T790M-cis-L792F/STAT3 Tyr705/IL-4 pathway could be a potential strategy to suppress osimertinib resistance in NSCLC.

FUNDING

This work was supported by the National Natural Science Foundation of China (81871889, 82072586, 81902910), Beijing Natural Science Foundation (7212084, 7214249), the China National Natural Science Foundation Key Program (81630071), the National Key Research and Development Project (2019YFC1315704), CAMS Innovation Fund for Medical Sciences (CIFMS 2021-1-I2M-012), Aiyou Foundation (KY201701) and CAMS Key Laboratory of translational research on lung cancer (2018PT31035).

Roles for macrophage-polarizing interleukins in cancer immunity and immunotherapy

Macrophages are the most abundant and one of the most critical cells of tumor immunity. They provide a bridge between innate and adaptive immunity through releasing cytokines into the tumor microenvironment (TME). A number of interleukin (IL) cytokine family members is involved in shaping the final phenotype of macrophages toward either a classically-activated pro-inflammatory M1 state with anti-tumor activity or an alternatively-activated anti-inflammatory M2 state with pro-tumor activity. Shaping TME macrophages toward the M1 phenotype or recovering this phenotypic state may offer a promising therapeutic approach in patients with cancer. Here, we focus on the impact of macrophage-polarizing ILs on immune cells and IL-mediated cellular cross-interactions within the TME. The key aim of this review is to define therapeutic schedules for addressing ILs in cancer immunotherapy based on their multi-directional impacts in such a milieu. Gathering more knowledge on this area is also important for defining adverse effects related to cytokine therapy and addressing them for reinforcing the efficacy of immunotherapy against cancer.

M2-phenotype tumour-associated macrophages upregulate the expression of prognostic predictors MMP14 and INHBA in pancreatic cancer

Pancreatic cancer is one of the most lethal gastrointestinal tumours, the most common pathological type is pancreatic adenocarcinoma (PAAD). In recent year, immune imbalanced in tumour microenvironment has been shown to play an important role in the evolution of tumours progression, and the efficacy of immunotherapy has been gradually demonstrated in clinical practice. In this study, we propose to construct an immune-related prognostic risk model based on immune-related genes MMP14 and INHBA expression that can assess the prognosis of pancreatic cancer patients and identify potential therapeutic targets for pancreatic cancer, to provide new ideas for the treatment of pancreatic cancer. We also investigate the correlation between macrophage infiltration and MMP14 and INHBA expression. First, the gene expression data of pancreatic cancer and normal pancreatic tissue were obtained from The Cancer Genome Atlas Program (TCGA) and The Genotype-Tissue Expression public database (GTEx). The differentially expressed immune-related genes between pancreatic cancer samples and normal sample were screened by R software. Secondly, univariate Cox regression analysis were used to evaluate the relationship between immune-related genes and the prognosis of pancreatic cancer patients. A polygenic risk score model was constructed by Cox regression analysis. The prognostic nomogram was constructed, and its performance was evaluated comprehensively by internal calibration curve and C-index. Using the risk model, each patient gets a risk score, and was divided into high- or low- risk groups. The proportion of 22 types of immune cells infiltration in pancreatic cancer samples was inferred by CIBERSOFT algorithm, correlation analysis (Pearson method) was used to analyse the correlation between the immune-related genes and immunes cells. Then, we applied macrophage conditioned medium to culture pancreatic cancer cell line PANC1, detected the expression of MMP14 and INHBA by qRT-PCR and Western blot methods. Knock-down MMP14 and INHBA in PANC1 cells by transfected with shRNA lentiviruses. Detection of migration ability of pancreatic cells was done by trans-well cell migration assay. A subcutaneous xenograft tumour model of human pancreatic cancer in nude mice was constructed. In conclusion, an immune-related gene prognostic model was constructed, patients with high-risk scores have poorer survival status, M2-phenotype tumour-associated macrophages (TAMs) up-regulate two immune-related genes, MMP14 and INHBA, which were used to establish the prognostic model. Knock-down of MMP14 and INHBA inhibited invasion of pancreatic cancer.

Involvement of IL-4, IL-13 and Their Receptors in Pancreatic Cancer

Interleukin (IL)-4 and IL-13 are known as pleiotropic Th2 cytokines with a wide range of biological properties and functions especially in immune responses. In addition, increasing activities have also been determined in oncogenesis and tumor progression of several malignancies. It is now generally accepted that IL-4 and IL-13 can exert effects on epithelial tumor cells through corresponding receptors. Type II IL-4 receptor (IL-4Rα/IL-13Rα1), predominantly expressed in non-hematopoietic cells, is identified to be the main target for both IL-4 and IL-13 in tumors. Moreover, IL-13 can also signal by binding to the IL-13Rα2 receptor. Structural similarity due to the use of the same receptor complex generated in response to IL-4/IL-13 results in overlapping but also distinct signaling pathways and functions. The aim of this review was to summarize knowledge about IL-4 and IL-13 and their receptors in pancreatic cancer in order understand the implication of IL-4 and IL-13 and their receptors for pancreatic tumorigenesis and progression and for developing possible new diagnostic and therapeutic targets.

Dioscin elicits anti-tumour immunity by inhibiting macrophage M2 polarization via JNK and STAT3 pathways in lung cancer

Tumour‐associated macrophage (TAM) is an important component in tumour microenvironment. Generally, TAM exhibits the function of M2‐like macrophage, which was closely related to angiogenesis and tumour progression. Dioscin, a natural steroidal saponin, has shown its powerful anti‐tumour activity recently. However, the mechanism of dioscin involved in immune regulation is still obscure. Here, we observed dioscin induced macrophage M2‐to‐M1 phenotype transition in vitro and inhibited IL‐10 secretion. Meanwhile, the phagocytosis of macrophages was enhanced. In subcutaneous lung tumour models, dioscin inhibited the augmentation of M2 macrophage populations. Furthermore, dioscin down‐regulated STAT3 and JNK signalling pathways in macrophages in vitro. In BMDMs, activating JNK and inhibiting STAT3 induce macrophages to M1 polarization while inhibiting JNK and activating STAT3 to M2 polarization. Additionally, condition mediums from dioscin‐pre‐treated macrophages inhibited the migration of 3LL cells and the tube‐formation capacity of HUVECs. What's more, dioscin‐mediated macrophage polarization inhibited the in vivo metastasis of 3LL cells. In conclusion, dioscin may act as a new anti‐tumour agent by inhibiting TAMs via JNK and STAT3 pathways in lung cancer.

Poor clinical outcomes of intratumoral dendritic cell-specific intercellular adhesion molecule 3-grabbing non-integrin-positive macrophages associated with immune evasion in gastric cancer

AIM

Tumour-associated macrophages (TAMs) are prominent immune cells infiltrating in solid tumours with phenotypic and functional heterogeneity. However, the clinical significance of heterogeneous subtypes of TAMs in gastric cancer still remains obscure. Here, we aimed to explore the clinical significance of TAMs expressing dendritic cell-specific intercellular adhesion molecule 3-grabbing non-integrin (DC-SIGN) and its relevance with immune contexture in gastric cancer.

METHODS

We selected 453 formalin-fixed and paraffin-embedded samples and 51 fresh tissue specimens of patients with gastric cancer from Zhongshan Hospital. The association of DC-SIGN⁺ macrophages with clinicopathological parameters, overall survival (OS) and responsiveness to fluorouracil-based adjuvant chemotherapy (ACT) was inspected. Immunohistochemistry (IHC) and flow cytometry (FCM) were applied to characterize immune cells in gastric cancer.

RESULTS

We demonstrated that high intratumoral DC-SIGN⁺ macrophages infiltration predicted poor OS and inferior therapeutic responsiveness to fluorouracil-based ACT in patients with gastric cancer. Furthermore, higher infiltration of DC-SIGN⁺ macrophages indicated an increased number of Foxp3⁺ regulatory T cells (Tregs), CD8⁺ T cells and a higher ratio of Foxp3⁺/CD8⁺ within the tumour microenvironment (TME). In addition, CD8⁺ T cells in DC-SIGN⁺ macrophages high subgroup were functionally impaired, showing decreased interferon-γ (IFN-γ), granzyme B (GZMB) and perforin production yet elevated programmed cell death protein 1 (PD-1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) expression.

CONCLUSIONS

DC-SIGN⁺ macrophages were associated with immunoinvasive TME and indicated poor prognosis and inferior therapeutic responsiveness to fluorouracil-based ACT. DC-SIGN⁺ macrophages might be an independent prognosticator and a potential immunotherapeutic target for gastric cancer.

Activation of the IL-4/STAT6 Signaling Pathway Promotes Lung Cancer Progression by Increasing M2 Myeloid Cells

Emerging evidence shows that signal transducer and activator of transcription 6 (STAT6) plays critical roles in tumor development. We previously found high-level expression of STAT6 in human lung adenocarcinoma and squamous cell carcinoma, specifically in infiltrated immune cells located in the lung interstitium. Nevertheless, the role of STAT6 signaling in lung carcinogenesis and lung cancer proliferation and its underlying mechanisms remain unclear. This study aimed to investigate the role of STAT6 and the interaction between STAT6 and the tumor microenvironment in pulmonary tumorigenesis. We established a murine model of primary lung carcinogenesis in STAT6-deficient (STAT6^−/−) and STAT6 wild-type (WT) BALB/c mice using the carcinogen urethane. Two-month-old male mice were intraperitoneally injected with urethane (1 g/kg) dissolved in phosphate buffered saline (PBS). Primary tumors were monitored in vivo by positron emission tomography scanning. At 4, 6, and 9 months after urethane injection, lung tumors were harvested from the STAT6^−/− and WT mice for analysis. Small interfering RNA was used to downregulate the expression of STAT6 in tumor cells. Fluorescence activated cell sorting analysis was used to analyze fluorescence-conjugated cell markers. Transwell assays were used in coculturing experiments. STAT6 protein expression was detected by Western blotting, immunohistochemistry, and immunofluorescence. STAT6 mRNA expression was detected by quantitative real time-polymerase chain reaction. Cell Counting Kit-8 and colony formation assays were performed to evaluate cell proliferation. We detected high expression of STAT6 in CD11b⁺ cells of lung carcinoma. Our results indicate that STAT6 deficiency inhibits carcinogen-induced tumor growth and improves prognosis. STAT6 deficiency also decreased the mobilization and differentiation of CD11b⁺ cells. STAT6 deficiency in CD11b⁺ cells but not tumor cells decreased interleukin (IL)-4 secretion and the differentiation of CD11b⁺ cells into M2 macrophage cells. In conclusion, our findings indicate that IL-4/STAT6 signaling in CD11b⁺ cells promotes lung cancer progression by triggering an IL-4 positive feedback loop and increasing M2 myeloid cells. STAT6 may be a new therapeutic target for the prevention and treatment of lung cancer.

Common Molecular Alterations in Canine Oligodendroglioma and Human Malignant Gliomas and Potential Novel Therapeutic Targets

Spontaneous canine (Canis lupus) oligodendroglioma (ODG) holds tremendous potential as an immunocompetent large animal model of human malignant gliomas (MG). However, the feasibility of utilizing this model in pre-clinical studies depends on a thorough understanding of the similarities and differences of the molecular pathways associated with gliomas between the two species. We have previously shown that canine ODG has an immune landscape and expression pattern of commonly described oncogenes similar to that of human MG. In the current study, we performed a comprehensive analysis of canine ODG RNAseq data from 4 dogs with ODG and 2 normal controls to identify highly dysregulated genes in canine tumors. We then evaluated the expression of these genes in human MG using Xena Browser, a publicly available database. STRING-database inquiry was used in order to determine the suggested protein associations of these differentially expressed genes as well as the dysregulated pathways commonly enriched by the protein products of these genes in both canine ODG and human MG. Our results revealed that 3,712 (23%) of the 15,895 differentially expressed genes demonstrated significant up- or downregulation (log2-fold change > 2.0). Of the 3,712 altered genes, ~50% were upregulated (n = 1858) and ~50% were downregulated (n = 1854). Most of these genes were also found to have altered expression in human MG. Protein association and pathway analysis revealed common pathways enriched by members of the up- and downregulated gene categories in both species. In summary, we demonstrate that a similar pattern of gene dysregulation characterizes both human MG and canine ODG and provide additional support for the use of the canine model in order to therapeutically target these common genes. The results of such therapeutic targeting in the canine model can serve to more accurately predict the efficacy of anti-glioma therapies in human patients.

Potential Contributions of Antioxidants to Cancer Therapy: Immunomodulation and Radiosensitization

Antioxidants play important roles in the maintenance of cellular integrity and thus are critical in maintaining the homeostasis of the host immune system. A balance between the levels of pro-oxidants and antioxidants defines the cellular fate of genomic integrity via maintaining the redox status of the cells. An aberration in this balance modulates host immunity that affects normal cellular signaling pathways resulting in uncontrolled proliferation of cells leading to neocarcinogenesis. For decades, there have been scientific debates on the use of antioxidants for the treatment of human cancers. This review is focused on current updates on the implications of antioxidant use as adjuncts in cancer therapy with an emphasis on immunomodulation and radiosensitization.

Tumor-related interleukins: old validated targets for new anti-cancer drug development

In-depth knowledge of cancer molecular and cellular mechanisms have revealed a strong regulation of cancer development and progression by the inflammation which orchestrates the tumor microenvironment. Immune cells, residents or recruited, in the inflammation milieu can have rather contrasting effects during cancer development. Accumulated clinical and experimental data support the notion that acute inflammation could exert an immunoprotective effect leading to tumor eradication. However, chronic immune response promotes tumor growth and invasion. These reactions are mediated by soluble mediators or cytokines produced by either host immune cells or tumor cells themselves. Herein, we provide an overview of the current understanding of the role of the best-validated cytokines involved in tumor progression, IL-1, IL-4 and IL-6; in addition to IL-2 cytokines family, which is known to promote tumor eradication by immune cells. Furthermore, we summarize the clinical attempts to block or bolster the effect of these tumor-related interleukins in anti-cancer therapy development.