IL-36 signalling enhances a pro-tumorigenic phenotype in colon cancer cells with cancer cell growth restricted by administration of the IL-36R antagonist

The role of interleukin-36 in health and disease states

The interleukin (IL)-1 superfamily upregulates immune responses and maintains homeostasis between the innate and adaptive immune systems. Within the IL-1 superfamily, IL-36 plays a pivotal role in both innate and adaptive immune responses. Of the four IL-36 isoforms, three have agonist activity (IL-36α, IL-36β, IL-36γ) and the fourth has antagonist activity (IL-36 receptor antagonist [IL-36Ra]). All IL-36 isoforms bind to the IL-36 receptor (IL-36R). Binding of IL-36α/β/γ to the IL-36R recruits the IL-1 receptor accessory protein (IL-1RAcP) and activates downstream signalling pathways mediated by nuclear transcription factor kappa B and mitogen-activated protein kinase signalling pathways. Antagonist binding of IL-36Ra to IL-36R inhibits recruitment of IL-1RAcP, blocking downstream signalling pathways. Changes in the balance within the IL-36 cytokine family can lead to uncontrolled inflammatory responses throughout the body. As such, IL-36 has been implicated in numerous inflammatory diseases, notably a type of pustular psoriasis called generalized pustular psoriasis (GPP), a chronic, rare, potentially life-threatening, multisystemic skin disease characterised by recurrent fever and extensive sterile pustules. In GPP, IL-36 is central to disease pathogenesis, and the prevention of IL-36-mediated signalling can improve clinical outcomes. In this review, we summarize the literature describing the biological functions of the IL-36 pathway. We also consider the evidence for uncontrolled activation of the IL-36 pathway in a wide range of skin (e.g., plaque psoriasis, pustular psoriasis, hidradenitis suppurativa, acne, Netherton syndrome, atopic dermatitis and pyoderma gangrenosum), lung (e.g., idiopathic pulmonary fibrosis), gut (e.g., intestinal fibrosis, inflammatory bowel disease and Hirschsprung's disease), kidney (e.g., renal tubulointerstitial lesions) and infectious diseases caused by a variety of pathogens (e.g., COVID-19; Mycobacterium tuberculosis, Pseudomonas aeruginosa, Streptococcus pneumoniae infections), as well as in cancer. We also consider how targeting the IL-36 signalling pathway could be used in treating inflammatory disease states.

IL-36 antagonism blunts the proliferation and migration of oral squamous cell carcinoma cells

IL-36 is known to mediate inflammation and fibrosis. Nevertheless, IL-36 signalling axis has also been implicated in cancer, although understanding of exact contribution of IL-36 to cancer progression is very limited, partly due to existence of multiple IL-36 ligands with agonistic and antagonistic function. Here we explored the role of IL-36 in oral squamous cell carcinoma (OSCC). Firstly, we analyzed expression of IL-36 ligands and receptor and found that the expression of IL-36γ was significantly higher in head and neck cancer (HNSCC) than that of normal tissues, and that the high expression of IL-36γ predicted poor clinical outcomes. Secondly, we investigated the direct effect of IL-36γ on OSCC cells and found that IL-36γ stimulated proliferation of OSCC cells with high expression of IL-36R expression. Interestingly, IL-36γ also promoted migration of OSCC cells with low to high IL-36R expression. Critically, both proliferation and migration of OSCC cells induced by IL-36γ were abrogated by anti-IL-36R mAb. Fittingly, RNA sequence analysis revealed that IL-36γ regulated genes involved in cell cycle and cell division. In summary, our results showed that IL-36γ can be a tumor-promoting factor, and targeting of IL-36R signalling may be a beneficial targeted therapy for patients with abnormal IL-36 signalling.

IL-36 signaling pathway dysregulation in Crimean-Congo hemorrhagic fever virus patients: A potential therapeutic avenue

Crimean-Congo hemorrhagic fever (CCHF) is a severe viral disease. The scientific literature is growing, emphasizing the significance of the interleukin (IL)-36 family in the proinflammatory signaling pathway. However, to date, no research has explored the potential of IL-36 family members as biomarkers in CCHF. This study aims to bridge this gap by evaluating IL-36α, IL-36β, and IL-36γ levels in CCHF patients and healthy controls and investigating their association with disease severity and prognosis. Sixty confirmed CCHF patients and 29 healthy controls were enrolled in this case-control study. Serum levels of IL-36α, IL-36β, and IL-36γ were measured using enzyme-linked immunosorbent assays. Significantly higher levels of IL-36α and IL-36β were observed in CCHF patients compared to healthy controls (p < 0.05). However, no statistically significant changes were found in IL-36γ levels between the two groups. Among the CCHF patients, those who did not survive exhibited significantly elevated IL-36α and IL-36γ levels compared to survivors (p < 0.01). Positive correlations were identified between IL-36α and IL-36γ levels with activated partial thromboplastin time, and D-dimer (p < 0.01). Conversely, platelet levels showed a negative correlation with IL-36α and IL-36γ levels (p < 0.01). The increased levels of IL-36α, IL-36β, and IL-36γ in patients indicate their participation in proinflammatory reactions in CCHF patients. Understanding the role of IL-36 family members in CCHF pathogenesis could offer valuable insights into disease progression and facilitate the development of targeted therapeutic strategies.

Lipid nanoparticle-based mRNA delivery systems for cancer immunotherapy

Cancer immunotherapy, which harnesses the power of the immune system, has shown immense promise in the fight against malignancies. Messenger RNA (mRNA) stands as a versatile instrument in this context, with its capacity to encode tumor-associated antigens (TAAs), immune cell receptors, cytokines, and antibodies. Nevertheless, the inherent structural instability of mRNA requires the development of effective delivery systems. Lipid nanoparticles (LNPs) have emerged as significant candidates for mRNA delivery in cancer immunotherapy, providing both protection to the mRNA and enhanced intracellular delivery efficiency. In this review, we offer a comprehensive summary of the recent advancements in LNP-based mRNA delivery systems, with a focus on strategies for optimizing the design and delivery of mRNA-encoded therapeutics in cancer treatment. Furthermore, we delve into the challenges encountered in this field and contemplate future perspectives, aiming to improve the safety and efficacy of LNP-based mRNA cancer immunotherapies.

New insights on IL‑36 in intestinal inflammation and colorectal cancer (Review)

Interleukin (IL)-36 is a member of the IL-1 superfamily, which includes three receptor agonists and one antagonist and exhibits a familial feature of inflammatory regulation. Distributed among various tissues, such as the skin, lung, gut and joints, the mechanism of IL-36 has been most completely investigated in the skin and has been used in clinical treatment of generalized pustular psoriasis. Meanwhile, the role of IL-36 in the intestine has also been under scrutiny and has been shown to be involved in the regulation of various intestinal diseases. Inflammatory bowel disease and colorectal cancer are the most predominant inflammatory and neoplastic diseases of the intestine, and multiple studies have identified a complex role for IL-36 in both of them. Indeed, inhibiting IL-36 signaling is currently regarded as a promising therapeutic approach. Therefore, the present review briefly describes the composition and expression of IL-36 and focuses on the role of IL-36 in intestinal inflammation and colorectal cancer. The targeted therapies that are currently being developed for the IL-36 receptor are also discussed.

IL-36 expression is increased in NSCLC with IL-36 stimulation of lung cancer cells promoting a pro-tumorigenic phenotype

The IL-36 cytokines are a recently described subset of the IL-1 family of cytokines, and have been shown to play a role in the pathogenesis of respiratory diseases such as asthma and COPD. Given the common aetiological links between COPD and lung cancer development, as well as the involvement of other IL-1 family members in lung tumorigenesis, the aim of this work was to investigate the role of IL-36 cytokines in the pathogenesis of lung cancer. In this study we demonstrate that expression of IL-36 cytokines and receptor mRNA and protein are significantly increased in lung cancer tissue compared to adjacent non-tumour tissue. In vitro assays showed that stimulation of two lung cancer cell lines, SKMES-1 human squamous cell and LLC murine lung cancer, with IL-36R agonists resulted in increased cellular migration and proliferation. All IL-36 cytokines induced the expression of pro-inflammatory chemokines in both lung cancer cell lines with synergistic effects identified upon co-stimulation of cells with IL-17, IL-22 and TNFα. Furthermore, we report that IL-36 cytokines induce protein expression of the immune checkpoint inhibitor protein PD-L1 on lung cancer cells. Taken together, this data indicates that targeting IL-36R signalling may be a useful targeted therapy for lung cancer patients with IL-36R⁺ cancer cells.

Transcriptomic and functional analyses reveal a tumour-promoting role for the IL-36 receptor in colon cancer and crosstalk between IL-36 signalling and the IL-17/ IL-23 axis

BACKGROUND

The interleukin (IL)-36 cytokines are a sub-family of the IL-1 family which are becoming increasingly implicated in the pathogenesis of inflammatory diseases and malignancies. Initial studies of IL-36 signalling in tumorigenesis identified an immune-mediated anti-tumorigenic function for these cytokines. However, more recent studies have shown IL-36 cytokines also contribute to the pathogenesis of lung and colorectal cancer (CRC).

METHODS

The aim of this study was to investigate IL-36 expression in CRC using transcriptomic datasets and software such as several R packages, Cytoscape, GEO2R and AnalyzeR. Validation of results was completed by qRT-PCR on both cell lines and a patient cohort. Cellular proliferation was assessed by flow cytometry and resazurin reduction.

RESULTS

We demonstrate that IL-36 gene expression increases with CRC development. Decreased tumoral IL-36 receptor expression was shown to be associated with improved patient outcome. Our differential gene expression analysis revealed a novel role for the IL-36/IL-17/IL-23 axis, with these findings validated using patient-derived samples and cell lines. IL-36γ, together with either IL-17a or IL-22, was able to synergistically induce different genes involved in the IL-17/IL-23 axis in CRC cells and additively induce colon cancer cell proliferation.

CONCLUSIONS

Collectively, this data support a pro-tumorigenic role for IL-36 signalling in colon cancer, with the IL-17/IL-23 axis influential in IL-36-mediated colon tumorigenesis.

Regulation of Interleukin-36γ/IL-36R Signaling Axis by PIN1 in Epithelial Cell Transformation and Breast Tumorigenesis

Simple Summary

Members of the interleukin (IL)-1 cytokine family exhibit dual functions in the regulation of inflammation and cancer. Recent studies have shown the critical role of IL-36γ, the newly identified IL-1 family member, in the regulation of cellular processes implicated in the progression of cancer. Therefore, the underlying mechanism of IL-36γ in tumor development is of considerable interest. Here, we identified the pivotal role of IL-36γ in the proliferation of breast cancer cells. Consistently, IL-36γ was found to promote epithelial cell transformation via the activation of c-Fos, c-Jun, and AP-1 transcription factors, followed by the IL36R-mediated MEK/ERK and JNK/c-Jun cascades. Furthermore, our findings demonstrate the critical role of PIN1 in the regulation of IL-36γ-induced mammary gland tumorigenesis.

Abstract

Given the increasing recognition of the relationship between IL-1 cytokines, inflammation, and cancer, the significance of distinct members of the IL-1 cytokine family in the etiology of cancer has been widely researched. In the present study, we investigated the underlying mechanism of the IL-36γ/IL-36R axis during breast cancer progression, which has not yet been elucidated. Initially, we determined the effects of IL-36γ on the proliferation and epithelial cell transformation of JB6 Cl41 mouse epidermal and MCF7 human breast cancer cells using BrdU incorporation and anchorage-independent growth assays. We found that treatment with IL-36γ increased the proliferation and colony formation of JB6 Cl41 and MCF7 cells. Analysis of the mechanism underlying the neoplastic cell transformation revealed that IL-36γ induced IL-36R-mediated phosphorylation of MEK1/2, ERK1/2, JNK1/2, and c-Jun, resulting in increased c-Fos, c-Jun, and AP-1 activities in JB6 Cl41 and MCF7 cells. Furthermore, the IL-36γ-induced tumorigenic capacity of MCF7 cells was considerably enhanced by PIN1, following MEK/ERK and JNK/c-Jun signaling. Interestingly, blocking PIN1 activity using juglone suppressed the IL-36γ-induced increase in the anchorage-independent growth of 4T1 metastatic mouse breast cancer cells. Finally, in a syngeneic mouse model, IL-36γ-induced tumor growth in the breast mammary gland was significantly inhibited following PIN1 knockout.