Distinctive expression pattern of interleukin-17 cytokine family members in colorectal cancer. Tumour Biol. 2016;37:1609-1615. [PMID: 26304506 DOI: 10.1007/s13277-015-3941-x]

IL-17 family cytokines in inflammatory or autoimmune skin diseases

As potent pro-inflammatory mediators, IL-17 family cytokines play crucial roles in the pathogenesis of various inflammatory and autoimmune skin disorders. Although substantial progress has been achieved in understanding the pivotal role of IL-17A signaling in psoriasis, leading to the development of highly effective biologics, the functions of other IL-17 family members in inflammatory or autoimmune skin diseases remain less explored. In this review, we provide a comprehensive overview of IL-17 family cytokines and their receptors, with a particular focus on the recent advancements in identifying cellular sources, receptors and signaling pathways regulated by these cytokines. At the end, we discuss how the aberrant functions of IL-17 family cytokines contribute to the pathogenesis of diverse inflammatory or autoimmune skin diseases.

Interleukin-17F suppressed colon cancer by enhancing caspase 4 mediated pyroptosis of endothelial cells

The combination of anti-angiogenic treatment and immunotherapy presents a promising strategy against colon cancer. Interleukin-17F (IL-17F) emerges as a critical immune cell cytokine expressed in colonic epithelial cells, demonstrating potential in inhibiting angiogenesis. In order to clarify the roles of IL-17F in the colon cancer microenvironment and elucidate its mechanism, we established a mouse colon carcinoma cell line CT26 overexpressing IL-17F and transplanted it subcutaneously into syngeneic BALB/c mice. We also analyzed induced colon tumor in IL-17F knockout and wild type mice. Our results demonstrated that IL-17F could suppress colon tumor growth in vivo with inhibited angiogenesis and enhanced recruitment of cysteine-cysteine motif chemokine receptor 6 (CCR6) positive immune cells. Additionally, IL-17F suppressed the tube formation, cell growth and migration of endothelial cells EOMA in vitro. Comprehensive bioinformatics analysis of transcriptome profiles between EOMA cells and those treated with three different concentrations of IL-17F identified 109 differentially expressed genes. Notably, a potential new target, Caspase 4, showed increased expressions after IL-17F treatment in endothelial cells. Further molecular validation revealed a novel downstream signaling for IL-17F: IL-17F enhanced Caspase 4/GSDMD signaling of endothelial cells, CT26 cells and CT26 transplanted tumors, while IL-17F knockout colon tumors exhibited decreased Caspase 4/GSDMD signaling. The heightened expression of the GSDMD N-terminus, coupled with increased cellular propidium iodide (PI) uptake and lactate dehydrogenase (LDH) release, revealed that IL-17F promoted pyroptosis of endothelial cells. Altogether, IL-17F could modulate the colon tumor microenvironment with inhibited angiogenesis, underscoring its potential as a therapeutic target for colon cancer.

Genetic association of circulating interleukins and risk of colorectal cancer: A bidirectional Mendelian randomization study

BACKGROUND

Previous studies have reported that inflammation, especially interleukin family members, plays an important role in the development of colorectal cancer (CRC). However, because of various confounders and the lack of clinical randomized controlled trial, the causal relationship between genetically predicted level of interleukin family and CRC risk has not been fully explained.

OBJECTIVE

Bi-directional Mendelian randomization (MR) was conducted to investigate the causal association between interleukin family members and CRC.

METHODS

Several genetic variables were extracted as instrumental variables (IVs) from summary data of genome-wide association studies (GWAS) for interleukin and CRC. IVs of interleukin family were obtained from recently published GWAS studies and the summary data of CRC was from FinnGen Biobank. After a series of quality control measures and strict screening, six models were used to evaluate the causal relationship. Pleiotropy, heterogeneity test, and a variety of sensitivity analysis were also used to estimate the robustness of the model results.

RESULTS

Genetically predicted higher circulating levels of IL-2 (odds ratio [OR]: 0.76; 95% confidence interval [CI]: 0.63-0.92; p = .0043), IL-17F(OR: 0.78; 95% CI: 0.62-1.00; p = .015), and IL-31 (OR: 0.88; 95% CI: 0.79-0.98; p = .023) were suggestively associated with decreased CRC risk. However, higher level of IL-10 (OR: 1.40; 95% CI: 1.18-1.65; p = .000094) was causally associated with increased risk of CRC. Reverse MR results indicated that the exposure of CRC was suggestively associated with higher levels of IL-36α (OR: 1.23; 95% CI: 1.01-1.49; p = .040) and IL-17RD (OR: 1.22; 95% CI, 1.00-1.48; p = .048) and lower level of IL-13 (OR: 0.78; 95% CI: 0.65-0.95; p = .013). The overall MR results did not provide evidence for causal relationships between other interleukins and CRC (p > .05).

CONCLUSION

We offer suggestive evidence supporting a potential causal relationship between circulating interleukins and CRC, underscoring the significance of targeting circulating interleukins as a strategy to mitigate the incidence of CRC.

Association between new plasma inflammatory markers and risk of colorectal neoplasms in individuals over 50 years old

OBJECTIVE(S)

The prognostic value of systemic cytokine profiles and inflammatory markers in colorectal cancer were explored by several studies. We want to know more about inflammatory biomarkers in colorectal adenoma and early cancer.

METHOD

The level of 38 inflammatory markers in the plasma of 112 adenoma patients, 72 Tis-T1 staging of colorectal carcinoma patients, 34 T2-T4 staging of colorectal carcinoma patients and 53 normal subjects were detected and compared.

RESULT(S)

Eight inflammatory biomarkers (Eotaxin, GCSF, IL-4, IL-5, IL-17E, MCP-1, TNF-α and VEGF-A) have higher plasma concentrations in colorectal adenoma and cancer patients compared with normal participants over 50 years old.

CONCLUSION(S)

Inflammatory markers may have the prognostic value for colorectal adenoma and early-stage carcinoma.

A novel immune-related prognostic signature based on Chemoradiotherapy sensitivity predicts long-term survival in patients with esophageal squamous cell carcinoma

Background

There is a heterogenous clinical response following chemoradiotherapy (CRT) in esophageal squamous cell carcinoma (ESCC). Therefore, we aimed to study signaling pathway genes that affect CRT sensitivity and prognosis.

Methods

Gene expression analyses were performed in the GEO and TCGA datasets. A immunohistochemistry (IHC) analysis was performed in pretreatment biopsies.

Results

MMP13 was found to be highly expressed in the "Pathologic Complete Response (pCR)" and "Complete Remission (CR)" and "Alive" groups. Th17 cells and MMP9/13 showed a negative correlation in immune infiltration analysis. In GSEA analysis, IL-4 and IL-13 signaling pathways were highly enriched in patients exhibiting high MMP expression in pCR and CR groups. IHC results suggested higher MMP13 & IL-4 and lower IL-17A & RORC expression in the CR group compared to the 0.70, and the model could well distinguish high-risk and low-risk subgroups.

Conclusion

The above results may provide guidance for developing novel treatment and prognostic strategies in ESCC patients.

Interleukin 17 in early invasive breast cancer

Introduction

Interleukin 17 (IL-17) has a key role in inflammatory responses. Increased serum concentrations of IL-17 have been reported in patients with different types of cancer. Some studies suggest antitumor activity of IL-17 while others speak in favor of its association with poorer prognosis. The lack of data on IL-17 behavior in vivo hinders the efforts to clarify the exact role of IL-17 in breast cancer patients and precludes the usage of IL-17 as potential therapeutic target.

Methods

The study included 118 patients with early invasive breast cancer. The serum concentration of IL-17A was measured before surgery and during adjuvant treatment and compared with healthy controls. The correlation of serum IL-17A concentration and different clinical and pathological parameters, including IL-17A expression in the corresponding tumor tissue samples, was analyzed.

Results

Significantly higher serum concentrations of IL-17A were found in women with early breast cancer before surgery, but also during adjuvant treatment in comparison to healthy controls. No significant correlation to tumor tissue IL-17A expression was observed. There was a significant postoperative decrease of serum IL-17A concentrations even in patients with relatively lower preoperative values. A significant negative correlation was found between serum IL-17A concentrations and the tumor estrogen receptor expression.

Conclusion

The results suggest that the immune response in early breast cancer is mediated by IL-17A, particularly in triple-negative breast cancer. IL-17A-mediated inflammatory response subsides postoperatively, but IL-17A concentrations remain elevated compared to the values in healthy controls, even after the removal of the tumor.

Emerging roles for IL-25 and IL-33 in colorectal cancer tumorigenesis

Colorectal cancer (CRC) is the second leading cause of cancer-related death worldwide, and is largely refractory to current immunotherapeutic interventions. The lack of efficacy of existing cancer immunotherapies in CRC reflects the complex nature of the unique intestinal immune environment, which serves to maintain barrier integrity against pathogens and harmful environmental stimuli while sustaining host-microbe symbiosis during homeostasis. With their expression by barrier epithelial cells, the cytokines interleukin-25 (IL-25) and IL-33 play key roles in intestinal immune responses, and have been associated with inappropriate allergic reactions, autoimmune diseases and cancer pathology. Studies in the past decade have begun to uncover the important roles of IL-25 and IL-33 in shaping the CRC tumour immune microenvironment, where they may promote or inhibit tumorigenesis depending on the specific CRC subtype. Notably, both IL-25 and IL-33 have been shown to act on group 2 innate lymphoid cells (ILC2s), but can also stimulate an array of other innate and adaptive immune cell types. Though sometimes their functions can overlap they can also produce distinct phenotypes dependent on the differential distribution of their receptor expression. Furthermore, both IL-25 and IL-33 modulate pathways previously known to contribute to CRC tumorigenesis, including angiogenesis, tumour stemness, invasion and metastasis. Here, we review our current understanding of IL-25 and IL-33 in CRC tumorigenesis, with specific focus on dissecting their individual function in the context of distinct subtypes of CRC, and the potential prospects for targeting these pathways in CRC immunotherapy.

Interleukin-17 Family Cytokines in Metabolic Disorders and Cancer

Interleukin-17 (IL-17) family cytokines are potent drivers of inflammatory responses. Although IL-17 was originally identified as a cytokine that induces protective effects against bacterial and fungal infections, IL-17 can also promote chronic inflammation in a number of autoimmune diseases. Research in the last decade has also elucidated critical roles of IL-17 during cancer development and treatment. Intriguingly, IL-17 seems to play a role in the risk of cancers that are associated with metabolic disorders. In this review, we summarize our current knowledge on the biochemical basis of IL-17 signaling, IL-17′s involvement in cancers and metabolic disorders, and postulate how IL-17 family cytokines may serve as a bridge between these two types of diseases.

Targeting interleukin-17 enhances tumor response to immune checkpoint inhibitors in colorectal cancer

Although immune checkpoint inhibitors (ICIs) have gained much attention in managing cancer, only a minority of patients, especially those with tumors that have been classified as immunologically "cold" such as microsatellite stable (MSS) colorectal cancers (CRC), experience clinical benefit from ICIs. Surprisingly, interleukin-17 (IL-17) and its primary source Th17 are enriched in CRC and inversely associated with patient outcome. Our previous study revealed that IL-17A could upregulate programmed death-ligand 1 (PD-L1) expression and impede the efficacy of immunotherapy. IL-17, therefore, can be a possible target to sensitize tumor cells to ICIs. The detailed clinical results from our trial, which is the first to show the benefits of the combination of anti-PD-1 with anti-IL-17 therapy for MSS CRC, have also been presented. In this review, we highlight the role of IL-17 in ICIs resistance and summarize the current clinical evidence for the use of combination therapy. Directions for future strategies to warm up immunologically "cold" MSS CRCs have also been proposed.

Integrin-Linked Kinase Expression Characterizes the Immunosuppressive Tumor Microenvironment in Colorectal Cancer and Regulates PD-L1 Expression and Immune Cell Cytotoxicity

Integrin-linked kinase (ILK) has been implicated as a molecular driver and mediator in both inflammation and tumorigenesis of the colon. However, a role for ILK in the tumor microenvironment (TME) and immune evasion has not been investigated. Here, we show a correlation of ILK expression with the immunosuppressive TME and cancer prognosis. We also uncover a role for ILK in the regulation of programmed death-ligand 1 (PD-L1) expression and immune cell cytotoxicity. Interrogation of web-based data-mining platforms, showed upregulation of ILK expression in tumors and adjacent-non tumor tissue of colorectal cancer (CRC) associated with poor survival and advanced stages. ILK expression was correlated with cancer-associated fibroblast (CAFs) and immunosuppressive cell infiltration including regulatory T cells (Treg) and M2 macrophages (M2) in addition to their gene markers. ILK expression was also significantly correlated with the expression of different cytokines and chemokines. ILK expression showed pronounced association with different important immune checkpoints including PD-L1. Deletion of the ILK gene in PD-L1 positive CRC cell lines using a doxycycline inducible-CRISPR/Cas9, resulted in suppression of both the basal and IFNγ-induced PD-L1 expression via downregulating NF-κB p65. This subsequently sensitized the CRC cells to NK92 immune cell cytotoxicity. These findings suggest that ILK can be used as a biomarker for prognosis and immune cell infiltration in colon cancer. Moreover, ILK could provide a therapeutic target to prevent immune evasion mediated by the expression of PD-L1.

Variable roles of interleukin-17F in different cancers

BACKGROUND

Interleukin (IL)-17 family is a group of six cytokines that plays a central role in inflammatory processes and participates in cancer progression. Interleukin-17A has been shown to have mainly a protumorigenic role, but the other members of the IL-17 family, including IL-17F, have received less attention.

METHODS

We applied systematic review guidelines to study the role of IL-17F, protein and mRNA expression, polymorphisms, and functions, in cancer. We carried out a systematic search in PubMed, Ovid Medline, Scopus, and Cochrane libraries, yielding 79 articles that met the inclusion criteria.

RESULTS

The findings indicated that IL-17F has both anti- and protumorigenic roles, which depend on cancer type and the molecular form and location of IL-17F. As an example, the presence of IL-17F protein in tumor tissue and patient serum has a protective role in oral and pancreatic cancers, whereas it is protumorigenic in prostate and bladder cancers. These effects are proposed to be based on multiple mechanisms, such as inhibition of angiogenesis, vasculogenic mimicry and cancer cell proliferation, migration and invasion, and aggravating the inflammatory process. No solid evidence emerged for the correlation between IL-17F polymorphisms and cancer incidence or patients' prognosis.

CONCLUSION

IL-17F is a multifaceted cytokine. There is a clear demand for more well-designed studies of IL-17F to elucidate its molecular mechanisms in different types of cancer. The studies presented in this article examined a variety of different designs, study populations and primary/secondary outcomes, which unfortunately reduces the value of direct interstudy comparisons.

Interleukin-25: New perspective and state-of-the-art in cancer prognosis and treatment approaches

Cancer is a leading cause of death which imposes a substantial financial burden. Among the several mechanisms involved in cancer progression, imbalance of immune cell-derived factors such as cytokines and chemokines plays a central role. IL-25, as a member of the IL-17 cytokine subfamily, exerts a paradoxical role in cancer, including tumor supportive and tumor suppressive. Hence, we have tried to clarify the role of IL-25 and its receptor in tumor progression and cancer prognosis. It has been confirmed that IL-25 exerts a tumor-suppressive role through inducing infiltration of eosinophils and B cells into the tumor microenvironment and activating the apoptotic pathways. In contrast, the tumor-supportive function has been implemented by activating inflammatory cascades, promoting cell cycle, and inducing type-2 immune responses. Since IL-25 has been dysregulated in tumor tissues and this dysregulation is involved in cancer development, its examination can be used as a tumor diagnostic and prognostic biomarker. Moreover, IL-25-based therapeutic approaches have shown promising results in cancer inhibition. In cancers in which IL-25 has a tumor-suppressive function, employing IL-25-enhancing approaches, such as Virulizin® and dihydrobenzofuran administration, has potentially inhibited tumor cell growth. On the other hand, in the case of IL-25-dependent tumor progression, using IL-25 blocking methods, including anti-IL-25 antibodies, might be a complementary approach to the other anticancer agent. Collectively, it is hoped, IL-25 might be a promising target in cancer treatment.

Robust rank aggregation and cibersort algorithm applied to the identification of key genes in head and neck squamous cell cancer

OBJECTIVE

Although multiple hub genes have been identified in head and neck squamous cell cancer (HNSCC) in recent years, because of the limited sample size and inconsistent bioinformatics analysis methods, the results are not reliable. Therefore, it is urgent to use reliable algorithms to find new prognostic markers of HNSCC.

METHOD

The Robust Rank Aggregation (RRA) method was used to integrate 8 microarray datasets of HNSCC downloaded from the Gene Expression Omnibus (GEO) database to screen differentially expressed genes (DEGs). Later, Gene Ontology (GO) functional annotation together with Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis was carried out to discover functions of those discovered DEGs. According to the KEGG results, those discovered DEGs showed tight association with the occurrence and development of HNSCC. Then cibersort algorithm was used to analyze the infiltration of immune cells of HNSCC and we found that the main infiltrated immune cells were B cells, dendritic cells and macrophages. A protein-protein interaction (PPI) network was established; moreover, key modules were also constructed to select 5 hub genes from the whole network using cytoHubba. 3 hub genes showed significant relationship with prognosis for TCGA-derived HNSCC patients.

RESULT

The potent DEGs along with hub genes were selected by the combined bioinformatic approach. AURKA, BIRC5 and UBE2C genes may be the potential prognostic biomarker and therapeutic targets of HNSCC.

CONCLUSIONS

The Robust Rank Aggregation method and cibersort algorithm method can accurately predict the potential prognostic biomarker and therapeutic targets of HNSCC through multiple GEO datasets.

Comprehensive analysis of long non-coding RNA and mRNA expression profile in rectal cancer

BACKGROUND

Rectal cancer (RC) is a malignant tumor that seriously threatens human health. Long non-coding RNAs (lncRNAs) play a vital role in tumor regulation. Nevertheless, their exact expression features and functions remain obscure, and therefore was the aim of the current study.

METHODS

We utilized the Affymetrix human GeneChip to screen differentially expressed profiles of lncRNAs and mRNAs from the cancer tissues and matched paracancer tissues of 6 RC patients. Gene Ontology (GO) and pathway enrichment analyses identified crucial functions and pathways of the aberrantly expressed mRNAs. We used quantitative real-time polymerase chain reaction to verify the significant expression differences of 11 candidate lncRNAs between the cancer and paracancer tissues. LncRNA-mRNA coexpression networks were built by calculating the Pearson correlation value to identify significant correlation pairs. Online bioinformatics tools GEPIA2, ONCOMINE, and PROGgeneV2 were used to mine the expression and prognosis of three crucial mRNAs and six verified lncRNAs. Competing endogenous RNA networks were constructed by predicting microRNA response elements and calculating free energy.

RESULTS

We found 1658 differentially expressed lncRNAs (778 up-regulated and 880 down-regulated) and 1783 aberrantly expressed mRNAs (909 up-regulated and 874 down-regulated). GO and pathway enrichment analyses revealed the vital functions of the differentially expressed mRNAs, including cell proliferation, cell migration, angiogenesis, and cellular response to zinc ion. The canonical signaling pathways mainly included the interleukin-17, cell cycle, Wnt, and mineral absorption signaling pathways. Six lncRNAs including AC017002.2 (P = 0.039), cancer susceptibility 19 (CASC19) (P = 0.021), LINC00152 (P = 0.013), NONHSAT058834 (P = 0.007), NONHSAT007692 (P = 0.045), and ENST00000415991.1 (P = 0.045) showed significant differences in expression levels between the cancer tissue and paracancer tissue groups. AC017002.2, NONHSAT058834, NONHSAT007692, and ENST00000415991.1 have not yet been reported in RC. The crucial mRNAs myelocytomatosis viral oncogene (MYC), transforming growth factor beta induced (TGFBI), and solute carrier family 7 member 5 (SLC7A5) were selected. AC017002.2 and LINC00152 were positively correlated with MYC, TGFBI, and cytochrome P450 family 2 sub-family B member 6 (All r > 0.900, P < 0.050). NONHSAT058834 was positively associated with MYC (r = 0.930, P < 0.001), and CASC19 was positively correlated with SLC7A5 (r = 0.922, P < 0.001).

CONCLUSION

This study offers convincing evidence of differentially expressed lncRNAs and mRNAs as potential biomarkers in RC.

The effect of interleukin-17F on vasculogenic mimicry in oral tongue squamous cell carcinoma

Oral tongue squamous cell carcinoma (OTSCC) is one of the most common cancers worldwide and is characterized by early metastasis and poor prognosis. Recently, we reported that extracellular interleukin-17F (IL-17F) correlates with better disease-specific survival in OTSCC patients and has promising anticancer effects in vitro. Vasculogenic mimicry (VM) is the formation of an alternative vasculogenic system by aggressive tumor cells, which is implicated in treatment failure and poor survival of cancer patients. We sought to confirm the formation of VM in OTSCC and to investigate the effect of IL-17F on VM formation. Here, we showed that highly invasive OTSCC cells (HSC-3 and SAS) form tube-like VM on Matrigel similar to those formed by human umbilical vein endothelial cells. Interestingly, the less invasive cells (SCC-25) did not form any VM structures. Droplet-digital PCR, FACS, and immunofluorescence staining revealed the presence of CD31 mRNA and protein in OTSCC cells. Additionally, in a mouse orthotopic model, HSC-3 cells expressed VE-cadherin (CD144) but lacked Von Willebrand Factor. We identified different patterns of VM structures in patient samples and in an orthotopic OTSCC mouse model. Similar to the effect produced by the antiangiogenic drug sorafenib, IL-17F inhibited the formation of VM structures in vitro by HSC-3 and reduced almost all VM-related parameters. In conclusion, our findings indicate the presence of VM in OTSCC and the antitumorigenic effect of IL-17F through its effect on the VM. Therefore, targeting IL-17F or its regulatory pathways may lead to promising therapeutic strategies in patients with OTSCC.

Much More Than IL-17A: Cytokines of the IL-17 Family Between Microbiota and Cancer

The interleukin-(IL-)17 family of cytokines is composed of six members named IL-17A, IL-17B, IL-17C, IL-17D, IL-17E, and IL-17F. IL-17A is the prototype of this family, and it was the first to be discovered and targeted in the clinic. IL-17A is essential for modulating the interplay between commensal microbes and epithelial cells at our borders (i.e., skin and mucosae), and yet, for protecting us from microbial invaders, thus preserving mucosal and skin integrity. Interactions between the microbiota and cells producing IL-17A have also been implicated in the pathogenesis of immune mediated inflammatory diseases and cancer. While interactions between microbiota and IL-17B-to-F have only partially been investigated, they are by no means less relevant. The cellular source of IL-17B-to-F, their main targets, and their function in homeostasis and disease distinguish IL-17B-to-F from IL-17A. Here, we intentionally overlook IL-17A, and we focus instead on the role of the other cytokines of the IL-17 family in the interplay between microbiota and epithelial cells that may contribute to cancer pathogenesis and immune surveillance. We also underscore differences and similarities between IL-17A and IL-17B-to-F in the microbiota-immunity-cancer axis, and we highlight therapeutic strategies that directly or indirectly target IL-17 cytokines in diseases.

Targeting the interleukin-17 immune axis for cancer immunotherapy

IL-17 plays versatile roles during tumorigenesis. Here, Vitiello and Miller summarize current knowledge in harnessing IL-17–producing γδ and Th17 cells for successful cancer immunotherapy.

The role of IL-17 in cancer remains controversial. Emerging evidence suggests that during early oncogenesis IL-17 supports tumor growth, whereas in established tumors IL-17 production by γδ and Th17 cells potentiates antitumor immunity. Consequently, γδ and Th17 cells are attractive targets for immunotherapy in the IL-17 immune axis. To optimize IL-17–based immunotherapy, a deeper understanding of the cytokines dictating IL-17 production and the polarity of γδ and Th17 cells is critical. Here, we delve into the dichotomous roles of IL-17 in cancer and provide insight into the tumor microenvironment conducive for successful IL-17–based γδ and Th17 cell immunotherapy.

Immunohistochemical expression of interleukin-17 and hormonal receptors in benign and malignant breast lesions

OBJECTIVES

IL17 is a critical pro-inflammatory cytokine that is involved in inflammation, multidrug resistance and growth persistence pathways in cancer. This study is aiming at studying the expression of IL17 and hormonal receptors expression in benign and malignant breast lesions using immunohistochemical staining methods.

RESULTS

A total of 137 cases of breast lesions were studied, 97 (70.8%) were malignant and 40 (29.2%) were benign cases. Age range for malignant and benign cases were between 26 and 80 years [mean age 50 ± 2 years], and 20 to 70 years [mean age 41 ± 4 years], respectively, Odds ratio = 2.3 [1.78-1.99, 95% CI]. The majority of the histopathological diagnosis of the benign and malignant lesions were 21 (15.3%) fibro-adenomas and 87 (63.5%) invasive ductal carcinoma, respectively. Expression of IL17 and age were insignificantly negatively correlated for both groups; benign cases [r = - 0.054, P value 0.742] and malignant cases [r = - 0.080, P value 0.444]. IL17 expression was showing insignificant association with age group, P value 0.065. IL17 expression showed a statistical significance based on the different histopathological diagnosis, P value 0.035. Expression levels of estrogen, progesterone, and human epidermal receptors were showing insignificant difference among IL17 expression categories, P values 0.678, 0.623, and 0.361, respectively.

Interleukin-6 compared to the other Th17/Treg related cytokines in inflammatory bowel disease and colorectal cancer

BACKGROUND

The connection between inflammatory bowel disease (IBD) and colorectal cancer (CRC) is well-established, as persistent intestinal inflammation plays a substantial role in both disorders. Cytokines may further influence the inflammation and the carcinogenesis process.

AIM

To compare cytokine patterns of active IBD patients with early and advanced CRC.

METHODS

Choosing a panel of cytokines crucial for Th17/Treg differentiation and behavior, in colon specimens, as mRNA biomarkers, and their serum protein levels.

RESULTS

We found a significant difference between higher gene expression of FoxP3, TGFb1, IL-10, and IL-23, and approximately equal level of IL-6 in CRC patients in comparison with IBD patients. After stratification of CRC patients, we found a significant difference in FoxP3, IL-10, IL-23, and IL-17A mRNA in early cases compared to IBD, and IL-23 alone in advanced CRC. The protein levels of the cytokines were significantly higher in CRC patients compared to IBD patients.

CONCLUSION

Our findings showed that IL-6 upregulation is essential for both IBD and CRC development until the upregulation of other Th17/Treg related genes (TGFb1, IL-10, IL-23, and transcription factor FoxP3) is a crucial primarily for CRC development. The significantly upregulated IL-6 could be a potential drug target for IBD and prevention of CRC development as well.

The Emerging Role of the IL-17B/IL-17RB Pathway in Cancer

Among inflammatory mediators, a growing body of evidence emphasizes the contribution of the interleukin 17 (IL-17) cytokine family in malignant diseases. Besides IL-17A, the prototypic member of the IL-17 family, several experimental findings strongly support the role of the IL-17B/IL-17 receptor B (IL-17RB) pathway in tumorigenesis and resistance to anticancer therapies. In mouse models, IL-17B signaling through IL-17RB directly promotes cancer cell survival, proliferation, and migration, and induces resistance to conventional chemotherapeutic agents. Importantly, recent work by our and other laboratories showed that IL-17B signaling dramatically alters the tumor microenvironment by promoting chemokine and cytokine secretion which foster tumor progression. Moreover, the finding that elevated IL-17B is associated with poor prognosis in patients with pancreatic, gastric, lung, and breast cancer strengthens the results obtained in pre-clinical studies and highlights its clinical relevance. Here, we review the current understanding on the IL-17B/IL-17RB expression patterns and biological activities in cancer and highlight issues that remain to be addressed to better characterize IL-17B and its receptor as potential targets for enhancing the effectiveness of the existing cancer therapies.

Helper Innate Lymphoid Cells in Human Tumors: A Double-Edged Sword?

Innate lymphoid cells (ILCs) were found to be developmentally related to natural killer (NK) cells. In humans, they are mostly located in “barrier” tissues where they contribute to innate defenses against different pathogens. ILCs are heterogeneous and characterized by a high degree of plasticity. ILC1s are Tbet⁺, produce interferon gamma and tumor necrosis factor alpha, but, unlike NK cells, are non-cytolytic and are Eomes independent. ILC2 (GATA-3+) secrete type-2 cytokines, while ILC3s secrete interleukin-22 and interleukin-17. The cytokine signatures of ILC subsets mirror those of corresponding helper T-cell subsets. The ILC role in defenses against pathogens is well-documented, while their involvement in tumor defenses is still controversial. Different ILCs have been detected in tumors. In general, the conflicting data reported in different tumors on the role of ILC may reflect the heterogeneity and/or differences in tumor microenvironment. The remarkable plasticity of ILCs suggests new therapeutic approaches to induce differentiation/switch toward ILC subsets more favorable in tumor control.

The connection between the Th17 cell related cytokines and cancer stem cells in cancer: Novel therapeutic targets

Cancer Stem Cells (CSCs) are the subpopulation of cells present in the different types of cancers with capabilities of self-renewal, differentiation, and tumorigenicity when transplanted into an animal host. The research work on the CSC has been providing a promising approach for the improvement of cancer therapies in the future. The CSCs have a close connection with the cytokines related with the T helper 17 (Th17) cell and other factors present in the tumor microenvironment, and these play a pivotal role in tumor progression and metastasis. The properties of CSCs are well defined in various type of tumor which is mainly developed by chemically and spontaneously in murine cancer model but in human defined primarily on acute myeloid leukemia, glioma, and breast cancer. The role of Th1, Th2, Natural Killer cells are well described in the cancer biology, but the Th17 cells are the subset which is recently exploited, and lots of research are going on. In this Review, we summarize current findings of the characteristics and functions of the Th17 cell and its signature cytokines in different cancers and their interconnections with cancer stem cells and with their markers. We have also discussed the functional properties of CSCs and how the CSCs markers can be distinguished from normal stem cells markers. We have also talked about the strategies that are efficiently targeting of CSCs and Th17 cells in different cancers.

Leukemic IL-17RB signaling regulates leukemic survival and chemoresistance

Secreted proteins provide crucial signals that have been implicated in the development of acute myeloid leukemia (AML) in the bone marrow microenvironment. Here we identify aberrant expressions of inflammatory IL-17B and its receptor (IL-17RB) in human and mouse mixed lineage leukemia-rearranged AML cells, which were further increased after exposure to chemotherapy. Interestingly, silencing of IL-17B or IL-17RB led to significant suppression of leukemic cell survival and disease progression in vivo. Moreover, the IL-17B-IL-17RB axis protected leukemic cells from chemotherapeutic agent-induced apoptotic effects. Mechanistic studies revealed that IL-17B promoted AML cell survival by enhancing ERK, NF-κB phosphorylation, and the expression of antiapoptotic protein B-cell lymphoma 2, which were reversed by small-molecule inhibitors. Thus, the inhibition of the IL-17B-IL-17RB axis may be a valid strategy to enhance sensitivity and therapeutic benefit of AML chemotherapy.-Guo, H.-Z., Niu, L.-T., Qiang, W.-T., Chen, J., Wang, J., Yang, H., Zhang, W., Zhu, J., Yu, S.-H. Leukemic IL-17RB signaling regulates leukemic survival and chemoresistance.

Interleukin-17F Has Anti-Tumor Effects in Oral Tongue Cancer

We recently showed that extracellular interleukin-17F (IL-17F) correlates with better disease-specific survival in oral tongue squamous cell carcinoma (OTSCC) patients. However, the underlying mechanisms of such effect remain obscure. Here, we used qRT-PCR to assess the expression of IL-17F and its receptors (IL-17RA and IL-17RC) in two OTSCC cell lines (HSC-3 and SCC-25) and in normal human oral keratinocytes (HOKs). IL-17F effects on cancer cell proliferation, migration, and invasion were studied using a live-imaging IncuCyte system, and a Caspase-3/7 reagent was used for testing apoptosis. 3D tumor spheroids were utilized to assess the impact of IL-17F on invasion with or without cancer-associated fibroblasts (CAFs). Tube-formation assays were used to examine the effects of IL-17F on angiogenesis using human umbilical vein endothelial cells (HUVEC). OTSCC cells express low levels of IL-17F, IL-17RA, and IL-17RC mRNA compared with HOKs. IL-17F inhibited cell proliferation and random migration of highly invasive HSC-3 cells. CAFs promoted OTSCC invasion in tumor spheroids, whereas IL-17F eliminated such effect. IL-17F suppressed HUVEC tube formation in a dose-dependent manner. Collectively, we suggest that IL-17F counteracts the pro-tumorigenic activity in OTSCC. Due to its downregulation in tumor cells and inhibitory activity in in vitro cancer models, targeting IL-17F or its regulatory pathways could lead to promising immunotherapeutic strategies against OTSCC.

IL-17 and colorectal cancer: From carcinogenesis to treatment

Colorectal cancer (CRC) is one of the most common types of cancer in the world. Several factors contribute to the development of this cancer. Tumor formation in colon triggers immune responses such as immune cells proliferation, phenotype alteration, cytokine synthesis and release, which lead to IL-17 producing T cells, the differentiated CD4+ T cells i.e. T helper 17. IL-17 is a pro-inflammatory cytokine, which its level is up regulated in serum and tissues of CRC patients. Several studies have shown that IL-17 has an important role in metastasis and prognosis of CRC. The aim of this review is to summarize the role of this cytokine in tumorigenesis, angiogenesis and metastasis of CRC and discuss its value in diagnosis, prognosis and treatment of CRC.

Genetic and molecular origins of colorectal Cancer among the Iranians: an update

BACKGROUND

Colorectal cancer (CRC) is one the leading causes of cancer related deaths among Iranians. Despite the various progresses in new therapeutic methods, it has still a low rate of survival. This high ratio of mortality is mainly related to the late diagnosis, in which the patients refer for treatment in advanced stages of tumor. MAIN BODY: colorectal cancer progression is largely associated with molecular and genetic bases. Although Iran has a high ratio of CRC mortality, there is not an efficient genetic panel for detection and prognosis. Therefore, it is critical to introduce new diagnostic markers with ability to detect in early stages.

CONCLUSION

Present review summarizes all of the genetic and epigenetic factors which are reported in CRC until now among the Iranian patients to pave the way of incorporation of new ethnic specific markers into the clinical practice and development of new targeted therapeutic methods.

Cytokine production by human neutrophils: Revisiting the "dark side of the moon"

Polymorphonuclear neutrophils are the most numerous leucocytes present in human blood, and function as crucial players in innate immune responses. Neutrophils are indispensable for the defence towards microbes, as they effectively counter them by releasing toxic enzymes, by synthetizing reactive oxygen species and by producing inflammatory mediators. Interestingly, recent findings have highlighted an important role of neutrophils also as promoters of the resolution of inflammation process, indicating that their biological functions go well beyond simple pathogen killing. Consistently, data from the last decades have highlighted that neutrophils may even contribute to the development of adaptive immunity by performing previously unanticipated functions, including the capacity to extend their survival, directly interact with other leucocytes or cell types, and produce and release a variety of cytokines. In this article, we will summarize the main features of, as well as emphasize some important concepts on, the production of cytokines by human neutrophils.

Interleukin-17 promotes the development of cisplatin resistance in colorectal cancer

Cisplatin (DDP)-based anticancer therapy is an important chemotherapeutic strategy for the treatment of colorectal cancer. However, its beneficial effect is largely compromised by adverse reactions, and more importantly, by the development of drug resistance. Therefore, it is crucial to determine the potential mechanism underlying the development of DDP resistance in colorectal cancer. Interleukin-17 (IL-17) is a proinflammatory cytokine that has been found to serve an important role in the host defense during cancer development. It has been suggested that IL-17 is key to promoting the development of resistance to DDP in several major types of cancer. However, the role of IL-17 in DDP resistance in colorectal cancer has not been extensively investigated. In the present study, it was observed that IL-17 was significantly upregulated in colorectal tumor samples, compared with the adjacent tissues. Furthermore, IL-17 was found to promote the viability of HCT116 colorectal cells treated with DDP, whilst blocking IL-17 signaling leading to HCT116 cell apoptosis. IL-17 was also shown to regulate the expression of several apoptosis-related proteins, including phosphorylated-protein kinase B (p-Akt), apoptosis regulator BAX (Bax), apoptosis regulator Bcl-2 (Bcl-2) and serine/threonine-protein kinase mTOR (mTOR). These findings indicated that IL-17 facilitates the development of DDP resistance in colorectal cancer by inhibiting cancer cell apoptosis through targeting p-Akt, Bax, Bcl-2 and mTOR. Overall, the findings of the present study suggest that a combination of DDP and an IL-17 inhibitor may prove to be a highly efficient strategy for colorectal cancer treatment.

Extracellular interleukin-17F has a protective effect in oral tongue squamous cell carcinoma

BACKGROUND

Oral tongue squamous cell carcinoma (SCC) is characterized by early metastasis and poor prognosis. Interleukin-17F (IL-17F) plays a protective role in many tumors. However, IL-17F expression in oral tongue SCC tissue has not been investigated.

METHODS

Immunostaining of 83 oral tongue SCC specimens and blinded-scoring were used to map IL-17F expression, location, and distribution. Survival curves were constructed according to Kaplan-Meier method. The Cox proportional hazard model was applied for univariate and multivariate survival analyses.

RESULTS

Mast cells are the major source of IL-17F in oral tongue SCC. In multivariate analysis, only the extracellular mast cell-derived IL-17F at the tumor invasion front was associated with better disease-specific survival in patients with all-stages and early-stages of oral tongue SCC.

CONCLUSION

Extracellular mast cell-derived IL-17F is antitumorigenic in oral tongue SCC. It separates patients with early-stage disease who are at high risk from patients who are at low risk. Furthermore, when analyzing tentative prognostic molecules, we conclude that in addition to the staining intensity, attention must be paid to the cellular source, distribution, and location of the molecule.

A Reappraisal on the Potential Ability of Human Neutrophils to Express and Produce IL-17 Family Members In Vitro: Failure to Reproducibly Detect It

Neutrophils are known to perform a series of effector functions that are crucial for the innate and adaptive responses, including the synthesis and secretion of a variety of cytokines. In light of the controversial data in the literature, the main objective of this study was to more in-depth reevaluate the capacity of human neutrophils to express and produce cytokines of the IL-17 family in vitro. By reverse transcription quantitative real-time PCR, protein measurement via commercial ELISA, immunohistochemistry (IHC) and immunofluorescence (IF), flow cytometry, immunoblotting, chromatin immunoprecipitation (ChIP), and ChIP-seq experiments, we found that highly pure (>99.7%) populations of human neutrophils do not express/produce IL-17A, IL-17F, IL-17AF, or IL-17B mRNA/protein upon incubation with a variety of agonists. Similar findings were observed by analyzing neutrophils isolated from active psoriatic patients. In contrast with published studies, IL-17A and IL-17F mRNA expression/production was not even found when neutrophils were incubated with extremely high concentrations of IL-6 plus IL-23, regardless of their combination with inactivated hyphae or conidia from Aspergillus fumigatus. Consistently, no deposition of histone marks for active (H3K27Ac) and poised (H3K4me1) genomic regulatory elements was detected at the IL-17A and IL-17F locus of resting and IL-6 plus IL-23-stimulated neutrophils, indicating a closed chromatin conformation. Concurrent experiments revealed that some commercial anti-IL-17A and anti-IL-17B antibodies (Abs), although staining neutrophils either spotted on cytospin slides or present in inflamed tissue samples by IHC/IF, do not recognize intracellular protein having the molecular weight corresponding to IL-17A or IL-17B, respectively, in immunoblotting experiments of whole neutrophil lysates. By contrast, the same Abs were found to more specifically recognize other intracellular proteins of neutrophils, suggesting that their ability to positively stain neutrophils in cytospin preparations and, eventually, tissue samples derives from IL-17A- or IL-17B-independent detections. In sum, our data confirm and extend, also at epigenetic level, previous findings on the inability of highly purified populations of human neutrophils to express/produce IL-17A, IL-17B, and IL-17F mRNAs/proteins in vitro, at least under the experimental conditions herein tested. Data also provide a number of justifications explaining, in part, why it is possible to false positively detect IL-17A⁺-neutrophils.

Expression and location of IL-17A, E, F and their receptors in colorectal adenocarcinoma: Comparison with benign intestinal disease

The research aimed to investigate secretion, expression and location of IL-17 relative ligands, IL-17 relative receptors, infiltrating inflammatory cells and parenchymal structural cells in colorectal cancer (CRC) compared with ulcerative colitis (UC) and benign hyperplastic polyp. 29 human intestinal tissues with CRC, 17 with UC and 7 with polyp were stained using immunohistochemistry to evaluate immunoreactivity for IL-17 family relative ligands including IL-17A, E, F and their respective relative receptors such as IL-17RA, IL-17RB and IL-17RC. At the same time the infiltration of inflammatory cells including lymphocytes, phagocytes, mast cells and neutrophils and parenchymal structural cell changes involving vascular endothelial cells and CD90⁺ fibroblast cells were also evaluated using the same methods The immunoreactivity or positive inflammatory cells of all the sections were analyzed using professional image analysis software to determine statistical significance. The immunoreactivity for IL-17A, IL-17RA, IL-17E, IL-17RB and IL-17F showed significant decrease in CRC tissue when compared to UC (p = 0.00001. respectively). The reduction of above IL-17 relative ligands and receptors was accompanied by an obvious decrease in the number of infiltrating neutrophils and mast cells in CRC (p = 0.00001 and p = 0.007, respectively) but accompanied by a marked increase of CD31⁺ blood vessels (p = 0.001). The immunoreactivity of IL-17A, IL-17RA, IL-17E, IL-17RB and IL-17F and the numbers of infiltrating neutrophils and mast cells showed significant decrease in CRC tissues when compared to those in polyp (p < 0.05). In contrast, the immunoreactivity of IL-17RC and the numbers of CD3⁺ 1ymphocytes were elevated in CRC when compared with those in polyp (p = 0.0001, p = 0.007, respectively). In CRC tissues, positive correlations between IL-17A, IL-17RA with CD68⁺ macrophages were observed respectively (r = 0.621, p = 0.0001; r = 0.75, p = 0.0001). IL-17 cytokine family including ligands and their corresponding receptors were secreted and expressed by infiltrating inflammatory cells. Not only infiltrating lymphocytes but also increased blood endothelial cells were relative significantly to genesis and progression of CRC.

The paradox of Th17 cell functions in tumor immunity

Immune system acts as a host defensive mechanism protecting against attacking pathogens and transformed cells, including cancer cells. Th17 cells are a specific subset of T helper lymphocytes determined by high secretion of IL-17 and other inflammatory cytokines. Th17 cells increase tumor progression by activating angiogenesis and immunosuppressive activities. They can also mediate antitumor immune responses through recruiting immune cells into tumors, stimulating effector CD8+ T cells, or surprisingly by altering toward Th1 phenotype and producing IFN-γ, so Th17 cells are supposed as a double-edged sword in cancer. A comprehensive approach to indicating the activity of Th17 cells in tumor progression could help in the planning of new therapeutic approaches specially targeting Th17 cells in cancer.

IL-17RB enhances thyroid cancer cell invasion and metastasis via ERK1/2 pathway-mediated MMP-9 expression

IL-17RB, a member of the IL-17 receptor family that can be activated by IL-17B, has been proved to be involved in inflammatory diseases and cancers. However, the function of IL-17RB in thyroid cancer is still unknown. In this study, IL-17RB expression in thyroid cancer cell lines and tissues was examined by real-time PCR and western blot. The effects of IL-17RB on cell invasion and migration were determined by in vitro invasion and migration assays, while the effects of IL-17RB on cell metastasis were analyzed by in vivo experiments. The results showed that IL-17RB expression was upregulated in both thyroid cancer cells and tissues. IL-17B dose-dependently promoted the invasion, growth and migration of thyroid cancer cells, whereas knockdown of IL-17RB attenuated the effects of IL-17B in vitro. Moreover, IL-17RB was involved in the metastasis and growth of thyroid cancer cells in vivo. In addition, IL-17RB induced ERK1/2 activation and increased MMP-9 expression in vitro and in vivo. Inhibition of ERK1/2 pathway blocked the IL-17RB-mediated thyroid cancer cell invasion and MMP-9 expression. Together, our findings demonstrate that IL-17RB can enhance thyroid cancer cell invasion and metastasis via ERK1/2 pathway-mediated MMP-9 expression, suggesting that IL-17RB may act as a potential therapeutic target for thyroid cancer therapy.

IL-17B: A new area of study in the IL-17 family

The interleukin (IL)-17 superfamily, a relatively new family of cytokines, consists of six ligands (from IL-17A to IL-17F), which bind to five receptor subtypes (from IL-17RA to IL-17RE) and induce downstream signaling. IL-17A, a prototype member of this family, has been reported to be involved in the pathogenesis of allergies, autoimmune diseases, allograft transplantations, and malignancies. Unlike IL-17A, which is mainly produced by T helper 17 cells, IL-17B is widely expressed in various tissues. Recently, the biological function of IL-17B in diseases, particularly tumors, has attracted the attention of researchers. We previously reported that the expression of IL-17RB increased in gastric cancer tissues and demonstrated that IL-17B/IL-17RB signaling plays a critical role in gastric tumor progression. However, studies on IL-17B are scant. In this review, we detail the structural characteristics, expression patterns, and biological activities of IL-17B and its potential role in the pathogenesis of diseases.

Targeting the Tumor Microenvironment: The Protumor Effects of IL-17 Related to Cancer Type

The inflammatory process contributes to immune tolerance as well as to tumor progression and metastasis. By releasing extracellular signals, cancerous cells constantly shape their surrounding microenvironment through their interactions with infiltrating immune cells, stromal cells and components of extracellular matrix. Recently, the pro-inflammatory interleukin 17 (IL-17)-producing T helper lymphocytes, the Th17 cells, and the IL-17/IL-17 receptor (IL-17R) axis gained special attention. The IL-17 family comprises at least six members, IL-17A, IL-17B, IL-17C, IL-17D, IL-17E (also called IL-25), and IL-17F. Secreted as disulfide-linked homo- or heterodimers, the IL-17 bind to the IL-17R, a type I cell surface receptor, of which there are five variants, IL-17RA to IL-17RE. This review focuses on the current advances identifying the promoting role of IL-17 in carcinogenesis, tumor metastasis and resistance to chemotherapy of diverse solid cancers. While underscoring the IL-17/IL-17R axis as promising immunotherapeutic target in the context of cancer managing, this knowledge calls upon further in vitro and in vivo studies that would allow the development and implementation of novel strategies to combat tumors.

Cytokine-Induced Modulation of Colorectal Cancer

The emergence of novel immunomodulatory cancer therapies over the last decade, above all immune checkpoint blockade, has significantly advanced tumor treatment. For colorectal cancer (CRC), a novel scoring system based on the immune cell infiltration in tumors has greatly improved disease prognostic evaluation and guidance to more specific therapy. These findings underline the relevance of tumor immunology in the future handling and therapeutic approach of malignant disease. Inflammation can either promote or suppress CRC pathogenesis and inflammatory mediators, mainly cytokines, critically determine the pro- or anti-tumorigenic signals within the tumor environment. Here, we review the current knowledge on the cytokines known to be critically involved in CRC development and illustrate their mechanisms of action. We also highlight similarities and differences between CRC patients and murine models of CRC and point out cytokines with an ambivalent role for intestinal cancer. We also identify some of the future challenges in the field that should be addressed for the development of more effective immunomodulatory therapies.