Promotion of lung tumor growth by interleukin-17

Matrix metalloproteinases targeting in prostate cancer

Prostate cancer (PCa) is one of the most common tumors affecting men all over the world. PCa has brought a huge health burden to men around the world, especially for elderly men, but its pathogenesis is unclear. In prostate cancer, epigenetic inheritance plays an important role in the development, progression, and metastasis of the disease. An important role in cancer invasion and metastasis is played by matrix metalloproteinases (MMPs), zinc-dependent proteases that break down extracellular matrix. We review two important forms of epigenetic modification and the role of matrix metalloproteinases in tumor regulation, both of which may be of significant value as novel biomarkers for early diagnosis and prognosis monitoring. The author considers that both mechanisms have promising therapeutic applications for therapeutic agent research in prostate cancer, but that efforts should be made to mitigate or eliminate the side effects of drug therapy in order to maximize quality of life of patients. The understanding of epigenetic modification, MMPs, and their inhibitors in the functional regulation of prostate cancer is gradually advancing, it will provide a new technical means for the prevention of prostate cancer, early diagnosis, androgen-independent prostate cancer treatment, and drug research.

Traversing through the Mechanistic Event Analysis in IL-6 and IL-17 Signaling for a New Therapeutic Paradigm in NSCLC

IL-6 and IL-17 are paradoxical cytokines that progress inflammatory states in chronic diseases, including cancer. In lung cancer, their role has been elucidated to favor cancer development by modulating signaling mechanisms critical to cellular growth. The intrinsic ability of these cytokines to influence macroautophagy is yet another reason to facilitate lung cancer. Here, we employed a systems immunology approach to discover the mechanistic role of these cytokines in cancer development. In a biological system, at later stages, the activation of NFkB stimulates immunosuppressive phenotypes to achieve tolerating effects in a transformed cell. We found that the upregulation of cytokines signaled M2 macrophages to modulate tumor responses through the activation of autophagic intermediates and inflammasome mediators. This caused immune perturbations in the tumor microenvironment, which were associated with cancer inflammation. To address these inflammatory states, we performed triggered event analysis to examine whether overexpressing immune effectors or downregulating immune suppressors may have an effect on cancer reversal. Interestingly, the inhibition of immune regulators opposed the model outcome to an increased immune response. Therefore, IL6-IL17-mediated regulation of lung cancer may address tumor malignancy and potentiate the development of newer therapeutics for NSCLC.

Comprehensive analysis of autophagy associated genes and immune infiltrates in cervical cancer

Objectives

Cervical cancer (CC) is the most common gynecological malignant tumor and the fourth leading cause of cancer-related death in women. The progression of CC is significantly affected by autophagy. Our objective was to use bioinformatics analysis to explore the expression, prognostic significance, and immune infiltration of autophagy-related genes in CC.

Materials and Methods

We identified a set of autophagy-related differentially expressed genes (ARDEGs) from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. ARDEGs were further validated by The Human Protein Atlas (HPA), GSE52903, and GSE39001 dataset. Hub genes were found by the STRING network and Cytoscape. We performed Gene Set Enrichment Analysis (GSEA), Gene ontology analysis (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, and immune infiltration analysis to further understand the functions of the hub genes. Kaplan-Meier (K-M) and receiver operating characteristic (ROC) were used to check the hub genes.

Results

A total of 10 up-regulated (CXCR4, BAX, SPHK1, EIF2AK2, TBK1, TNFSF10, ITGB4, CDKN2A, IL24, and BIRC5) and 19 down-regulated (PINK1, ATG16L2, ATG4D, IKBKE, MLST8, MAPK3, ERBB2, ULK3, TP53INP2, MTMR14, BNIP3, FOS, CCL2, FAS, CAPNS1, HSPB8, PTK6, FKBP1B , and DNAJB1) ARDEGs were identified. The ARDEGs were enriched in cell growth, apoptosis, human papillomavirus infection, and cytokine-mediated. Then, we found that low expression of MAPK3 was associated with poor prognosis in CC patients and was significantly enriched in immune pathways. In addition, the expression of MAPK3 was significantly positively correlated with the infiltration levels of macrophages, B cells, mast cell activation, and cancer-associated fibroblasts. Furthermore, MAPK3 was positively correlated with LGALS9, and negatively correlated with CTLA4 and CD40.

Conclusion

Our results show that MAPK3 can be used as a new prognostic biomarker to predict the prognosis of patients with CC.

Notopterol Suppresses IL-17-Induced Proliferation and Invasion of A549 Lung Adenocarcinoma Cells via Modulation of STAT3, NF-κB, and AP-1 Activation

Interleukine-17 is a proinflammatory cytokine that promotes lung cancer growth and progression though the activation of the STAT3, NF-κB, and AP-1 signaling pathways. Therefore, blocking the IL-17-induced oncogenic pathway is a new strategy for the treatment of lung cancer. Notopterol, a furanocoumarin, has demonstrated anti-tumor effects in several types of tumors. However, its molecular function in relation to the IL-17-induced proliferation and invasion of A549 lung adenocarcinoma cells remains unknown. Here, notopterol exhibited an inhibitory effect on IL-17-promoted A549 cell proliferation and induced G0/G1 cell cycle arrest. Western blot analysis revealed that notopterol inhibited the expression of cell-cycle-regulatory proteins, including cyclin D1, cyclin E, CDK4, and E2F. Moreover, notopterol blocked IL-17-induced A549 cell migration and invasion by regulating the epithelial-mesenchymal transition (EMT) and reducing the expression of extracellular degradation enzymes. At the molecular level, notopterol treatment significantly down-regulated the IL-17-activated phosphorylation of Akt, JNK, ERK1/2, and STAT3, leading to a reduced level of transcriptional activity of NF-κB and AP-1. Collectively, our results suggest that notopterol blocks IL-17-induced A549 cell proliferation and invasion through the suppression of the MAPK, Akt, STAT3, AP-1, and NF-κB signaling pathways, as well as modulating EMT.

The role of IL-17 in lung cancer growth

Interleukin 17 (IL-17) is an inflammatory cytokine with multiple roles in immune protection, immunopathology, and inflammation-related tumors. Lung cancer is inflammation-related cancer, and a large number of studies have shown that IL-17 contributes to the metastasis and progression of lung cancer. However, some studies have shown that IL17 inhibits the occurrence of lung cancer. At present, there is still some controversy about the role of IL17 in the occurrence and development of lung cancer. This review introduces the basic characteristics of IL-17 and focuses on its role in lung cancer, in order to provide a certain theoretical basis for the prevention, diagnosis, and treatment of lung cancer.

Novel Histopathological Biomarkers in Prostate Cancer: Implications and Perspectives

Prostate cancer (PCa) is the second most frequently diagnosed cancer in men. Despite the significant progress in cancer diagnosis and treatment over the last few years, the approach to disease detection and therapy still does not include histopathological biomarkers. The dissemination of PCa is strictly related to the creation of a premetastatic niche, which can be detected by altered levels of specific biomarkers. To date, the risk factors for biochemical recurrence include lymph node status, prostate-specific antigen (PSA), PSA density (PSAD), body mass index (BMI), pathological Gleason score, seminal vesicle invasion, extraprostatic extension, and intraductal carcinoma. In the future, biomarkers might represent another prognostic factor, as discussed in many studies. In this review, we focus on histopathological biomarkers (particularly CD169 macrophages, neuropilin-1, cofilin-1, interleukin-17, signal transducer and activator of transcription protein 3 (STAT3), LIM domain kinase 1 (LIMK1), CD15, AMACR, prostate-specific membrane antigen (PSMA), Appl1, Sortilin, Syndecan-1, and p63) and their potential application in decision making regarding the prognosis and treatment of PCa patients. We refer to studies that found a correlation between the levels of biomarkers and tumor characteristics as well as clinical outcomes. We also hypothesize about the potential use of histopathological markers as a target for novel immunotherapeutic drugs or targeted radionuclide therapy, which may be used as adjuvant therapy in the future.

IL-17 Cytokines and Chronic Lung Diseases

IL-17 cytokines are expressed by numerous cells (e.g., gamma delta (γδ) T, innate lymphoid (ILC), Th17, epithelial cells). They contribute to the elimination of bacteria through the induction of cytokines and chemokines which mediate the recruitment of inflammatory cells to the site of infection. However, IL-17-driven inflammation also likely promotes the progression of chronic lung diseases, such as chronic obstructive pulmonary disease (COPD), lung cancer, cystic fibrosis, and asthma. In this review, we highlight the role of IL-17 cytokines in chronic lung diseases.

The role of the programmed cell death protein-1/programmed death-ligand 1 pathway, regulatory T cells and T helper 17 cells in tumor immunity: a narrative review

Tumor immunotherapy, especially that involving programmed cell death protein-1 (PD-1)/programmed death-ligand 1 (PD-L1) immunosuppressive checkpoint inhibitors, has become an important part of tumor treatment strategy in the past decade. Blocking PD-1/PD-L1 signaling pathway can reduce the inhibitory effect of PD-1 pathway on T cells, promote the anti-tumor activity of activated T cells, and prolong the remission period of tumor. While PD-1/PD-L1 immunotherapy is effective in the treatment of solid malignant tumors, it also has shortcomings, due to the complexity of the tumor microenvironment (TME). Regulatory T cells (Tregs) and T helper 17 (Th17) cells play an important role in the TME and are closely related to the occurrence and development of tumors. Tregs can inhibit the anti-tumor immune effect, while Th17 cells play a dual role in tumor immunity, which not only promotes tumorigenesis but also promotes anti-tumor immunity. In the occurrence and development of tumor, PD-1/PD-L1 pathway, Tregs and Th17 cells are interrelated. However, the complicated relationship between the PD-1/PD-L1 pathway, Tregs, and Th17 cells has not been fully clarified. Here, we summarize the immunoregulation mechanisms and discuss the crosstalk between the PD-1/PD-L1 pathway, Tregs, and Th17 cells, with the aim of providing novel insights for future cancer treatment.

The Impact of the Deepwater Horizon Oil Spill upon Lung Health-Mouse Model-Based RNA-Seq Analyses

We used a transcriptomic approach to interrogate the effects of a saline-accommodated fraction from the Macondo 252 well (MC252) oil and Corexit dispersants on lung tissue. Wild-type C57BL/6 male and female mice were exposed on days 0, 7 and 13 by oropharyngeal aspiration to saline accommodated fractions (SAF) of crude oil from the Macondo (MC252) well, Corexit 9500, Corexit 9527, 9500+oil and 9527+oil or a saline solution as the vehicle control. These treatments did not cause overt toxicity, with the exception of the Corexit exposures which caused brief weight loss after the first exposure. On day 14, total RNA was isolated from the left lung for RNA-seq analyses. KEGG-pathway-based differential expression revealed that Corexit 9527 elicited the strongest changes involving the upregulation of 19 KEGG pathways (FDR < 0.10), followed by Corexit 9500 with the upregulation of seven pathways (FDR < 0.10). As an important signature, pathways related to a response to DNA damage (e.g., p53 signaling and mismatch repair) dominate those upregulated by Corexit 9527 and Corexit 9500. In addition, pro-inflammatory pathways (e.g., cytokine-cytokine receptor interaction, IL-17 signaling pathway and TNF signaling pathways) were upregulated selectively in oil-treated male mice. Surprisingly, oil + dispersant combinations caused lesser effects than the individual treatments at the transcriptomic level. Overall, these findings support potential genotoxicity, inflammation and cell death due to dispersant or oil exposures. Similar exposures to lung tumor bearing K-Ras^LA1 mice provided evidence for tumor promotion by oil and Corexit dispersant treatments. Our mouse RNA-seq analyses may be relevant to the pulmonary health hazards of MC252 oil and dispersants experienced in exposed populations.

Th17 Cells and IL-17 As Novel Immune Targets in Ovarian Cancer Therapy

Ovarian cancer (OC) is usually diagnosed at an advanced stage and is related with poor prognosis. Despite numerous studies, the pathogenesis of OC is still unknown. Recent studies indicate the role of the immune system in the development and spread of OC. The identification of factors and mechanisms involved in that process and their modulation is crucial for creating effective antitumor therapy. We investigated the potential role of Th17 cells in OC patients (n = 71) by analyzing the frequencies of Th17 cells in three different environments, i.e., peripheral blood (PB), peritoneal fluid (PF), and tissue (Th17 infiltrating cells), and the concentration of IL-17A in plasma and PF of patients in terms of their clinical and prognostic significance. Th17 cells were analyzed by flow cytometry as a percentage of CD4⁺ lymphocytes that expressed intracellular expression of IL-17A. The level of IL-17A in plasma and PF were determined by ELISA. Our results showed accumulation of Th17 cells among tumor-infiltrating CD4⁺ lymphocytes (p < 0.001 in relation to PB). Moreover, the percentage of Th17 cells in both PB and PF of OC patients was significantly lower than that in benign tumors group (n = 35). There were no significant differences in the percentage of Th17 cells in PB, PF, and tissue in relation to clinicopathological characteristics of OC patients and survival. The lower percentage of Th17 cells in the PB and PF of OC patients may promote evasion of host immune response by cancer cells. The concentration of IL-17A in plasma of OC patients was higher (p < 0.0001) than that in both benign tumors and control group (n = 10). The PF IL-17A level in OC patients was higher (p < 0.0001) than that in women with benign ovarian tumors, indicating its synthesis in OC microenvironment. Higher IL-17A level in PF is correlated with longer (median: 36.5 vs. 27 months) survival of OC patients.

Genetic alterations of interleukin-17 and related genes in human prostate cancer

Interleukin-17 (IL-17) has been shown to promote development of hormone-naïve prostate cancer (HNPC) and castration-resistant prostate cancer (CRPC) as well as lymph node metastasis in mouse models. Gene alterations of IL-17 family of cytokines and their downstream genes in human prostate cancer have not been investigated. We studied 7 datasets archived in cBioPortal and queried gene alterations in a total of 1303 cases of human prostate cancers. 35 genes were examined, including IL-17 family of cytokines and receptors, IL-17-downstream genes, and genes related to IL-17-downstream genes. We found that 34/35 (97%) genes had significantly more alterations in metastatic prostate cancer (with alteration rates ranging from 3.42% to 13.01%) than primary prostate cancer (with alteration rates ranging from 0.40% to 2.96%). 15/35 (43%) genes had significantly more alterations in primary CRPC than primary HNPC. 34/35 (97%) genes had significantly more alterations in metastatic CRPC than primary HNPC. Only three genes (S100A7, S100A8, and S100A9) had significantly more alterations in metastatic CRPC than primary CRPC. The gene alterations were mostly gene amplifications (97%), while gene deep deletions, missense mutations, and truncating mutations were very rare. 7/35 (20%) genes had significantly more alterations in primary neuroendocrine prostate cancer (NEPC) than primary adenocarcinoma (AC). 23/35 (66%) genes had significantly more alterations in metastatic NEPC than metastatic AC. Only three genes (S100A7, S100A8, and S100A9) had significantly more alterations in metastatic NEPC than metastatic AC with neuroendocrine features. Most of the gene alterations in metastatic NEPC were gene amplifications (80%), while gene deep deletions, missense mutations, and truncating mutations were very rare. Our findings suggest that gene amplifications of IL-17 and related genes are more frequently found in metastatic CRPC and NEPC than primary hormone-naïve prostate adenocarcinomas, implying that IL-17 and related genes may play important roles in the progression from HNPC to CRPC and from primary location to metastasis as well as in development of metastatic NEPC.

Immunopathogenesis of Immune Checkpoint Inhibitor-Related Adverse Events: Roles of the Intestinal Microbiome and Th17 Cells

The advent of novel, innovative, and effective anti-cancer immunotherapies has engendered an era of renewed optimism among cancer specialists and their patients. Foremost among these successful immunotherapies are monoclonal antibodies (MAbs) which target immune checkpoint inhibitor (ICI) molecules, most prominently cytotoxic T-lymphocyte-associated protein (CTLA-4) and programmed cell death protein-1 (PD-1) and its major ligand, PD-L1. These immunotherapeutic agents are, however, often associated with the occurrence of immune-mediated toxicities known as immune-related adverse events (IRAEs). The incidence of severe toxicities increases substantially when these agents are used together, particularly with CTLA-4 in combination with PD-1 or PD-L1 antagonists. Accordingly, dissociating the beneficial anti-tumor therapeutic activity of these agents from the emergence of IRAEs represents a significant challenge to attaining the optimum efficacy of ICI-targeted immunotherapy of cancer. This situation is compounded by an increasing awareness, possibly unsurprising, that both the beneficial and harmful effects of ICI-targeted therapies appear to result from an over-reactive immune system. Nevertheless, this challenge may not be insurmountable. This contention is based on acquisition of recent insights into the role of the gut microbiome and its products as determinants of the efficacy of ICI-targeted immunotherapy, as well as an increasing realization of the enigmatic involvement of Th17 cells in both anti-tumor activity and the pathogenesis of some types of IRAEs. Evidence linking the beneficial and harmful activities of ICI-targeted immunotherapy, recent mechanistic insights focusing on the gut microbiome and Th17 cells, as well as strategies to attenuate IRAEs in the setting of retention of therapeutic activity, therefore represent the major thrusts of this review.

Interleukin-17 Promotes Migration and Invasion of Human Cancer Cells Through Upregulation of MTA1 Expression

Interleukin-17 (IL-17) has been shown to promote development of prostate, colon, skin, lung, breast, and pancreatic cancer. The purpose of this study was to determine if IL-17 regulates MTA1 expression and its biological consequences. Human cervical cancer HeLa and human prostate cancer DU-145 cell lines were used to test if IL-17 regulates metastasis associated 1 (MTA1) mRNA and protein expression using quantitative reverse transcription-polymerase chain reaction and Western blot analysis, respectively. Cell migration and invasion were studied using wound healing assays and invasion chamber assays. Thirty-four human cervical tissues were stained for IL-17 and MTA1 using immunohistochemical staining. We found that IL-17 increased MTA1 mRNA and protein expression in both cell lines. Cell migration was accelerated by IL-17, which was abolished by knockdown of MTA1 expression with small interference RNA (siRNA). Further, cell invasion was enhanced by IL-17, which was eliminated by MTA1 knockdown. Human cervical intra-epithelial neoplasia (CIN) and cervical cancer tissues had increased number of IL-17-positive cells and MTA1 expression compared to normal cervical tissues. The number of IL-17-positive cells was positively correlated with MTA1 expression. These findings demonstrate that IL-17 upregulates MTA1 mRNA and protein expression to promote HeLa and DU-145 cell migration and invasion.

Comprehensive genomic and prognostic analysis of the IL‑17 family genes in lung cancer

The six members of the interleukin (IL)‑17 gene family (IL‑17A‑F) have been identified in various types of cancer. Although lung cancer is the leading cause of cancer‑related death worldwide and IL‑17A was found to play a critical role in lung cancer, there is little knowledge concerning the association between the other five members of the IL‑17 family and lung cancer. The genetic mutations and expression of IL‑17 family members were investigated using the Catalogue of Somatic Mutations in Cancer (COSMIC), Oncomine, and cBio Cancer Genomics Portal (cBioPortal) databases. Prognostic values and interaction networks of the members were assessed by the Kaplan‑Meier plotter, Search Tool for the Retrieval of Interacting Genes (STRING) database and FunRich software. The results found that, across 5,238 lung cancer patients in the cBioPortal, the results of IL‑17 family gene alteration frequencies and types showed that IL‑17A, IL‑25 and IL‑17F exhibited higher alteration frequencies (2, 2.1 and 1.9%, respectively), and gene amplification accounted for the majority of changes. IL‑17B, IL‑17C and IL‑17D exhibited lower alteration frequencies (0.8, 1.1 and 1.1%, respectively), and deep deletion accounted for the majority of changes. The rates of point mutations in IL‑17A through IL‑17F family genes in lung cancer were 0.66, 0.18, 0.13, 0.09, 0.27 and 0.44% in the COSMIC database. Within the Oncomine database, five datasets showed that IL‑17D was significantly decreased in lung cancer, while no dataset showed a significant difference in the expression of IL‑17A, IL‑17B, IL‑17C, IL‑25 or IL17‑F between lung cancer and normal controls. The frequencies of IL‑17A, IL‑17B and IL‑17C mRNA upregulation in lung squamous cell carcinoma were lower than those in lung adenocarcinoma (2.7, 1.9 and 2.1%, respectively), whereas the frequencies of IL‑17D, IL‑25 and IL‑17F mRNA upregulation were higher in lung squamous cell carcinoma than those in lung adenocarcinoma (3, 6 and 6%, respectively). IL‑17A and IL‑17B were unrelated to overall survival (p=0.11; P=0.17), whereas IL‑17C, IL‑17D, IL‑25 and IL‑17F influenced prognosis (P=0.0023, P=0.0059, P=0.039 and P=0.0017, respectively) according to the Kaplan‑Meier plotter. Moreover, the expression level of IL‑17C was the highest in lung tissues, and IL‑17 family genes mainly participate in the 'IFN‑γ pathway' according to the STRING database and Funrich software. In conclusion, we performed the first comprehensive investigation of the IL‑17 gene family in lung cancer, including gene mutation, mRNA expression levels, prognostic values and network pathways. Our results revealed that IL‑17 family gene mutation rates were in general low and that amplification and deep deletion were the main mutation type. The expression and function of IL‑17A and IL‑17B in lung cancer are still not fully elucidated and warrant research with larger sample sizes. IL‑17D was significantly decreased in lung cancer and was correlated with better OS. Studies of IL‑17C‑F in lung cancer are limited. Further experimental studies on the association between IL‑17D and lung cancer progression are needed to identify more effective therapeutic targets for lung cancer.

IL-17A promotes cell migration and invasion of glioblastoma cells via activation of PI3K/AKT signalling pathway

Glioblastomas (GBMs) are the most common of both benign and malignant primary brain tumours, in which the inflammatory and immunologic abnormalities are involved. Interleukin-17A (IL-17A) plays an important role in various inflammatory diseases and cancers. Several recent studies revealed that the expression of IL-17A was overexpressed in human GBMs tissue. However, the accurate role of IL-17A in GBMs remains unclear. In this study, we aimed to explore the effect of IL-17A on cell migration and invasion of GBMs and the mechanism by which the effects occurred. We found that exogenous IL-17A promoted significantly cell migration and invasion abilities in two GBMs cell lines (U87MG and U251) in a time-dependent manner. In addition, the protein expressions of PI3K, Akt and MMP-2/9 were increased in the GBMs cells challenged by IL-17A. Furthermore, a tight junction protein ZO-1 was down-regulated but Twist and Bmi1 were up-regulated. Treatment with a PI3K inhibitor (LY294002) significantly reduced the abilities of both migration and invasion in U87MG and U251 cells. LY294002 treatment also attenuated the IL-17A causing increases of protein levels of PI3K, AKT, MMP-2/9, Twist and the decreases of protein level of ZO-1 in the U87MG and U251 cells. Taken together, we concluded that IL-17A promotes the GBM cells migration and invasion via PI3K/AKT signalling pathway. IL-17A and its related signalling pathways may be potential therapeutic targets for GBM.

Role of p53 in the chronic pulmonary immune response to tangled or rod-like multi-walled carbon nanotubes

The fiber-like shape of multi-walled carbon nanotubes (MWCNTs) is reminiscent of asbestos, suggesting they pose similar health hazards when inhaled, including pulmonary fibrosis and mesothelioma. Mice deficient in the tumor suppressor p53 are susceptible to carcinogenesis. However, the chronic pathologic effect of MWCNTs delivered to the lungs of p53 heterozygous (p53^+/-) mice has not been investigated. We hypothesized that p53^+/- mice would be susceptible to lung tumor development after exposure to either tangled (t-) or rod-like (r-) MWCNTs. Wild-type (p53^+/+) or p53^+/- mice were exposed to MWCNTs (1 mg/kg) via oropharyngeal aspiration weekly over four consecutive weeks and evaluated for cellular and pathologic outcomes 11-months post-initial exposure. No lung or pleural tumors were observed in p53^+/+ or p53^+/- mice exposed to either t- or rMWCNTs. In comparison to tMWCNTs, the rMWCNTs induced the formation of larger granulomas, a greater number of lymphoid aggregates and greater epithelial cell hyperplasia in terminal bronchioles in both p53^+/- and p53^+/+ mice. A constitutively larger area of CD45R⁺/CD3⁺ lymphoid tissue was observed in p53^+/- mice compared to p53^+/+ mice. Importantly, p53^+/- mice had larger granulomas induced by rMWCNTs as compared to p53^+/+ mice. These findings indicate that a combination of p53 deficiency and physicochemical characteristics including nanotube geometry are factors in susceptibility to MWCNT-induced lymphoid infiltration and granuloma formation.

Interleukin‑17A and heparanase promote angiogenesis and cell proliferation and invasion in cervical cancer

Interleukin‑17A (IL‑17A) is a CD4 T-cell-derived pro-inflammatory cytokine that is involved in human cervical tumorigenesis. Heparanase (HPSE) is an endo-glycosidase expressed in mammals, which has been confirmed to be associated with cervical cancer invasion. In the present study, it was hypothesized that IL‑17A and HPSE are key proteins promoting tumor angiogenesis and cell proliferation and invasion in cervical cancer. The expression of IL‑17A and HPSE in cervical cancer tissues was detected by immunohistochemical staining. In addition, the expression of IL‑17A and HPSE was down- and upregulated via RNAi and human recombinant proteins, and MTT and Transwell assays were performed to examine cervical cancer cell proliferation and invasion, respectively. Flow cytometry analysis was also performed to detect cell cycle distribution, and the levels of target mRNA and protein were evaluated by reverse transcription-quantitative polymerase chain reaction and western blotting, respectively. IL‑17A and HPSE were highly expressed in cervical cancer tissues, and microvessel density was notably higher in the IL‑17A-positive group. IL‑17A and/or HPSE recombinant protein promoted the proliferation and invasion of cervical cancer cells, increased the proportion of cells in the G2/M phase, and enhanced the mRNA and protein expression of human papillomavirus E6, P53, vascular endothelial growth factor and CD31, whereas downregulation of IL‑17A and/or HPSE exerted the opposite effects. Furthermore, downregulation of IL‑17A and/or HPSE was found to inhibit the expression of nuclear factor (NF)-κB P65. In summary, IL‑17A and HPSE may promote tumor angiogenesis and cell proliferation and invasion in cervical cancer, possibly via the NF-κB signaling pathway. These findings may lead to the identification of new diagnostic markers and therapeutic targets.

A bi-specific inhibitor targeting IL-17A and MMP-9 reduces invasion and motility in MDA-MB-231 cells

The cytokine IL-17A is associated with the progression of various cancers, but little is known about the molecular cross-talk between IL-17A and other tumor-promoting factors. Previous studies have shown that the IL-17A-mediated invasion of breast cancer cells can be inhibited by selective antagonists of the matrix metalloproteinase 9 (MMP-9), suggesting that the cross-talk between IL-17A and MMP-9 may promote cancer invasiveness and metastasis. Here, we present a novel strategy for developing cancer therapeutics, based on the simultaneous binding and inhibition of both IL-17A and MMP-9. To this end, we use a bi-specific heterodimeric fusion protein, comprising a natural inhibitor of MMPs (N-TIMP2) fused with an engineered extracellular domain (V3) of the IL-17A receptor. We show that, as compared with the mono-specific inhibitors of IL-17A (V3) and MMP-9 (N-TIMP2), the engineered bi-specific fusion protein inhibits both MMP-9 activation and IL-17A-induced cytokine secretion from fibroblasts and exhibits a synergistic inhibition of both the migration and invasion of breast cancer cells. Our findings demonstrate, for the first time, that dual targeting of inflammatory (IL-17A) and extracellular matrix remodeling (MMP) pathways can potentially be used as a novel therapeutic approach against cancer. Moreover, the platform developed here for generating the bi-specific IL-17A/MMP-9 inhibitor can be utilized for generating bi-specific inhibitors for other cytokines and MMPs.

Increased interleukin-17A levels promote rituximab resistance by suppressing p53 expression and predict an unfavorable prognosis in patients with diffuse large B cell lymphoma

Rituximab resistance has become increasingly common in patients with diffuse large B cell lymphoma (DLBCL). However, the mechanisms involved remain unclear. In this study, we aimed to examine the effect of rituximab on interleukin (IL)-17A and to investigate the role of IL-17A in rituximab resistance and its prognostic value in patients with DLBCL. Our retrospective analysis revealed that rituximab increased IL-6 expression levels in patients with DLBCL, and the increased IL-6 levels in turn induced the differentiation of Th17 and IL-17⁺Foxp3⁺ Treg cells, which secreted IL-17A both in vivo and in vitro. We then examined the effects of IL-17A on the apoptosis and proliferation of, and p53 expression in DLBCL cells, and found that IL-17A prevented rituximab-induced apoptosis and promoted the proliferation of DLBCL cells by suppressing p53 expression in vitro. The survival data of 73 patients with DLBCL suggested that high peripheral blood levels of IL-17A predicted an unfavorable survival. On the whole, our data indicate that rituximab promotes Th17 and IL-17⁺Foxp3⁺ Treg cells to secrete IL-17A, which in turn promotes rituximab resistance, partially by suppressing p53 expression and inhibiting rituximab-induced DLBCL cell apoptosis. IL-17A may thus prove to be a useful prognostic marker in patients with DLBCL.

The Study of IL-10 and IL-17A Genes Expression in Patients with Different Stages of Asthma: a Case-Control Study

BACKGROUND

Asthma is considered as a complex disorder in which genetics and environment play crucial role in its susceptibility. In addition to the huge financial costs that significantly reduce the quality of life of the patients and their families, it causes high prevalence of lung diseases. Finding contributing new genetic factors involved in early diagnosis or progression of asthma can provide novel approaches for treatment or managing of asthma. In the present study, the potential role of two key cytokines of IL-10 and IL-17A was investigated in asthma pathogenesis.

MATERIALS AND METHODS

Using real-time PCR technique, we analyzed the expression levels of target genes in two groups of mild and severe asthma patient in comparison with healthy individuals.

RESULTS

In comparison with control population, obtained data showed 4 and 7-fold down-regulation of IL-17A in the group of mild and severe asthma, respectively. Down-regulation of IL-17A showed a significant correlation with progression of asthma severity. While IL-10 showed up to 10-fold down-regulation in the group of severe asthma, its expression level was not correlated with severity of asthma.

CONCLUSION

Obtained data revealed that deregulation IL-10 and IL-17A have potential to play crucial role in pathogenesis and prognosis of asthma. Observed down-regulation of these cytokines in blood cells suggests their usefulness as a marker in diagnosis of asthmatic types in patients.

Hyperinsulinemia enhances interleukin-17-induced inflammation to promote prostate cancer development in obese mice through inhibiting glycogen synthase kinase 3-mediated phosphorylation and degradation of interleukin-17 receptor

Interleukin-17 (IL-17) plays important roles in inflammation, autoimmune diseases, and some cancers. Obese people are in a chronic inflammatory state with increased serum levels of IL-17, insulin, and insulin-like growth factor 1 (IGF1). How these factors contribute to the chronic inflammatory status that promotes development of aggressive prostate cancer in obese men is largely unknown. We found that, in obese mice, hyperinsulinemia enhanced IL-17-induced expression of downstream proinflammatory genes with increased levels of IL-17 receptor A (IL-17RA), resulting in development of more invasive prostate cancer. Glycogen synthase kinase 3 (GSK3) constitutively bound to and phosphorylated IL-17RA at T780, leading to ubiquitination and proteasome-mediated degradation of IL-17RA, thus inhibiting IL-17-mediated inflammation. IL-17RA phosphorylation was reduced, while the IL-17RA levels were increased in the proliferative human prostate cancer cells compared to the normal cells. Insulin and IGF1 enhanced IL-17-induced inflammatory responses through suppressing GSK3, which was shown in the cultured cell lines in vitro and obese mouse models of prostate cancer in vivo. These findings reveal a mechanism underlying the intensified inflammation in obesity and obesity-associated development of aggressive prostate cancer, suggesting that targeting GSK3 may be a potential therapeutic approach to suppress IL-17-mediated inflammation in the prevention and treatment of prostate cancer, particularly in obese men.

Cancer cells induce interleukin-22 production from memory CD4+ T cells via interleukin-1 to promote tumor growth

IL-22 has been identified as a cancer-promoting cytokine that is secreted by infiltrating immune cells in several cancer models. We hypothesized that IL-22 regulation would occur at the interface between cancer cells and immune cells. Breast and lung cancer cells of murine and human origin induced IL-22 production from memory CD4+ T cells. In the present study, we found that IL-22 production in humans is dependent on activation of the NLRP3 inflammasome with the subsequent release of IL-1β from both myeloid and T cells. IL-1 receptor signaling via the transcription factors AhR and RORγt in T cells was necessary and sufficient for IL-22 production. In these settings, IL-1 induced IL-22 production from a mixed T helper cell population comprised of Th1, Th17, and Th22 cells, which was abrogated by the addition of anakinra. We confirmed these findings in vitro and in vivo in two murine tumor models, in primary human breast and lung cancer cells, and in deposited expression data. Relevant to ongoing clinical trials in breast cancer, we demonstrate here that the IL-1 receptor antagonist anakinra abrogates IL-22 production and reduces tumor growth in a murine breast cancer model. Thus, we describe here a previously unrecognized mechanism by which cancer cells induce IL-22 production from memory CD4+ T cells via activation of the NLRP3 inflammasome and the release of IL-1β to promote tumor growth. These findings may provide the basis for therapeutic interventions that affect IL-22 production by targeting IL-1 activity.

IL-17 in the lung: the good, the bad, and the ugly

The IL-17 family of cytokines has emerged over the last two decades as a pleiotropic group of molecules that function in a wide variety of both beneficial and detrimental (pathological) processes, mainly in mucosal barrier tissue. The beneficial effects of IL-17 expression are especially important in the lung, where exposure to foreign agents is abundant. IL-17A plays an important role in protection from both extracellular bacteria and fungi, as well as viruses that infect cells of the mucosal tracts. IL-17 coregulated cytokines, such as IL-22, are involved in maintaining epithelial cell homeostasis and participate in epithelial cell repair/regeneration following inflammatory insults. Thus, the IL-17/IL-22 axis is important in both responding to, and recovering from, pathogens. However, aberrant expression or overexpression of IL-17 cytokines contributes to a number of pathological outcomes, including asthma, pneumonitis, and generation or exacerbation of pulmonary fibrosis. This review covers the good, bad, and ugly aspects of IL-17 in the lung.

Interleukin-17A promotes esophageal adenocarcinoma cell invasiveness through ROS-dependent, NF-κB-mediated MMP-2/9 activation

Interleukin-17A (IL-17A), a pro-inflammatory cytokine secreted primarily by Th17 cells, has been proved to be involved in the microenvironment of certain inflammation-related tumors. However, the role of IL-17A in cancer development has always been controversial. In this study, we investigated the effect of IL-17A on the regulation of esophageal adenocarcinoma (EAC) cell invasiveness and related molecular mechanism. Surface IL-17 receptor (IL-17R) expression on human EAC cell line OE19 was examined using flow cytometry. The effect of IL-17A on cell proliferation was measured by MTT assay. Cell migration and invasive ability in vitro were assessed by wound-healing and Matrigel-coated Transwell invasion assay. Intracellular reactive oxygen species (ROS) levels were determined by flow cytometry and fluorescence microscope. The protein expression levels of MMP-2, MMP-9, NF-κB and p-IκB-α were detected by western blotting. Our results showed that IL-17A promoted migration and invasion of OE19 cells in a dose-dependent manner, however it had less effect on OE19 cell proliferation. Furthermore, IL-17A treatment significantly upregulated the expression of MMP-2 and MMP-9, stimulated intracellular ROS production, increased IκB-α phosphorylation and NF-κB nuclear translocation. Nevertheless, IL-17A-induced expression of MMP-2/9 and OE19 cell invasiveness were both inhibited by pretreatment with N-acetyl-L-cysteine (NAC, a ROS scavenger) or pyrrolidine dithiocarbamate (PDTC, a NF-κB inhibitor). In conclusion, these findings demonstrate that IL-17A can promote the migration and invasiveness of EAC cells through ROS/NF-κB/MMP-2/9 signaling pathway activation, indicating that IL-17A may be a potential therapeutic target for EAC.

The Role of Interleukin-17 in Lung Cancer

Tumour-associated inflammation is a hallmark of malignant carcinomas, and lung cancer is a typical inflammation-associated carcinoma. Interleukin-17 (IL-17) is an important inflammatory cytokine that plays an important role in chronic inflammatory and autoimmune diseases and in inflammation-associated tumours. Numerous studies have shown that IL-17 directly or indirectly promotes tumour angiogenesis and cell proliferation and that it inhibits apoptosis via the activation of inflammatory signalling pathways. Therefore, IL-17 contributes to the metastasis and progression of lung cancer. Research advances with respect to the role of IL-17 in lung cancer will be presented as a review in this paper.

[Role of Interleukin 17 in Lung Carcinogenesis and Lung Cancer Progression]

白介素-17（interleukin 17, IL-17）是一个重要的炎症因子，参与介导了机体的抗感染免疫及自身免疫性疾病相关的病理性炎症；此外，IL-17还与多种炎症相关的肿瘤有着密切联系。吸烟是导致肺癌的重要危险因素之一，而吸烟等因素所致的肺部慢性炎症反应伴有IL-17过表达，提示IL-17可能与肺癌的发生存在潜在联系；同时，IL-17还通过多种机制影响肺癌进展，本文对这一领域的相关研究进展进行了综述。

Identification of Novel Serum Autoantibodies for Differential Diagnosis of Autoimmune Pancreatitis and Pancreatic Ductal Adenocarcinoma

OBJECTIVES

The lack of specific biochemical markers is a major drawback for the diagnosis of autoimmune pancreatitis (AIP). The aims were to characterize the autoantibody profiles in AIP and pancreatic ductal adenocarcinoma (PDAC) and to identify circulating autoantibodies that could be diagnostic markers differentiating PDAC and the AIP subtypes.

METHODS

Tissue lysates obtained from the resected pancreas of patients with AIP and patients with PDAC were separated by 2-dimensional polyacrylamide gel electrophoresis subsequently immunoblotted with autologous sera. The immunoreactive spots were subjected to nanoscale liquid chromatography-electrospray ionization tandem mass spectrometry to identify serum autoantibodies to tissue-derived autoantigens associated with AIP and PDAC. Autoantibody concentrations for selected autoantigens were assessed by enzyme-linked immunosorbent assays.

RESULTS

A total of 115 immunoreactive spots were identified by 2-dimensional polyacrylamide gel electrophoresis/immunobloting. Nanoscale liquid chromatography-electrospray ionization tandem mass spectrometry-based analysis revealed 68 autoantigens in AIP, 26 in PDAC, and 21 present in both diseases. Assessment of 13 selected AIP autoantibody serum levels revealed that 7 of them had significantly higher titers in AIP versus PDAC. IgG-directed against transaldolase could significantly differentiate between the 2 AIP subtypes.

CONCLUSIONS

The novel panel of AIP autoantibodies is promising to supplement the predictive tests for AIP of the currently known autoantigens and represent a basis for a combined blood test to differentiate AIP from PDAC in the future.

Differential Diagnosis of Autoimmune Pancreatitis From Pancreatic Cancer by Analysis of Serum Gelatinase Levels

OBJECTIVES

The aim of this study was to analyze serum gelatinases as part of the clinical strategy for the preoperative differentiation between autoimmune pancreatitis (AIP) and pancreatic ductal adenocarcinoma (PDAC). The finding of differential markers will prevent unnecessary surgical resection and allow optimal treatment of these diseases.

METHODS

Quantitative gelatin zymography was applied to analyze all individual gelatinase forms in serum and to define proteinase alterations associated with AIP and PDAC. For this purpose, sera of 130 patients, being 29 with AIP, 33 with chronic pancreatitis, 32 with PDAC, and 36 healthy controls, were first assayed for gelatinase levels by quantitative zymography before further validation by the analysis with commercial sandwich enzyme linked immunosorbent assays.

RESULTS

Serum profiling data obtained by zymography analysis revealed that gelatinase B/matrix metalloproteinase 9 (MMP-9), the neutrophil gelatinase B-associated lipocalin/MMP-9 complex, and gelatinase A/MMP-2 levels were significantly increased in patients with AIP. These proteins are promising markers to discriminate between AIP and PDAC. The best composite parameter, being the ratio of total MMP-9 over MMP-2 levels, can predict 93% of the AIP and 75% of the PDAC correctly. With enzyme linked immunosorbent assay, we confirmed the zymography results.

CONCLUSIONS

Differential gelatinase serum profiles as AIP markers, together with other clinical tests, help to assure the diagnosis of PDAC or AIP.

The IL-17-Th1/Th17 pathway: an attractive target for lung cancer therapy?

INTRODUCTION

There is strong pharmaceutical development of agents targeting the IL-17-TH17 pathway for the treatment of psoriasis (Ps) and psoriatic arthritis (PsA). Lung cancer accounts for 28% of all cancer-related deaths worldwide, and roughly 80% of patients with newly-diagnosed non-small cell lung cancer (NSCLC) present with metastatic disease, with a poor prognosis of around 12 months. Therefore, there is a high unmet medical need for the development of new and potent systemic treatments in this deadly disease. The emergence of immunotherapies such as anti-PD-1 or anti-PDL1 as candidate therapies in non-small cell lung cancer (NSCLC) indicates that targeting critical immuno-modulatory cytokines including those within the IL-17-Th1/Th17 axis may have proven benefit in the treatment of lung cancer. Areas covered: In this review we describe the current evidence for aberrant IL-17-Th1/Th17 settings in cancer, particularly with regard to targeting this axis in NSCLC. We further discuss the current agents under pharmaceutical development which could potentially target this axis, and discuss the current limitations and areas of concern regarding the use of these in lung cancer. Expert opinion: Current evidence suggests that moving forward agents targeting the IL-17-Th1/Th17 pathway may have novel new oncoimmunology indications in the treatment paradigm for NSCLC.

Interleukin-17 promotes prostate cancer via MMP7-induced epithelial-to-mesenchymal transition

Chronic inflammation has been associated with a variety of human cancers including prostate cancer. Interleukin-17 (IL-17) is a critical pro-inflammatory cytokine, which has been demonstrated to promote development of prostate cancer, colon cancer, skin cancer, breast cancer, lung cancer, and pancreas cancer. IL-17 promotes prostate adenocarcinoma with a concurrent increase of matrix metalloproteinase 7 (MMP7) expression in mouse prostate. Whether MMP7 mediates IL-17’s action and the underlying mechanisms remain unknown. We generated Mmp7 and Pten double knockout (Mmp7^−/− in abbreviation) mouse model and demonstrated that MMP7 promotes prostate adenocarcinoma through induction of epithelial-to-mesenchymal transition (EMT) in Pten-null mice. MMP7 disrupted E-cadherin/β-catenin complex to up-regulate EMT transcription factors in mouse prostate tumors. IL-17 receptor C and Pten double knockout mice recapitulated the weak EMT characteristics observed in Mmp7^−/− mice. IL-17 induced MMP7 and EMT in human prostate cancer LNCaP, C4-2B, and PC-3 cell lines, while siRNA knockdown of MMP7 inhibited IL-17-induced EMT. Compound III, a selective MMP7 inhibitor, decreased development of invasive prostate cancer in Pten single knockout mice. In human normal prostates and prostate tumors, IL-17 mRNA levels were positively correlated with MMP7 mRNA levels. These findings demonstrate that MMP7 mediates IL-17’s function in promoting prostate carcinogenesis through induction of EMT, indicating IL-17-MMP7-EMT axis as potential targets for developing new strategies in the prevention and treatment of prostate cancer.

IL-17A-producing T cells are associated with the progression of lung adenocarcinoma

Accumulating evidence has shown that T cells are crucial in shaping the tumor microenvironment and regulating tumor development. However, the roles of IL-17A-producing T cells (IL-17A⁺CD4⁺ Th17, IL-17A⁺CD8⁺ Tc17 and IL-17A⁺ γδT17 cells) and related cytokines in the progression of lung cancer (LC) remain uncertain. Here, we found that the frequencies of both Th17 and γδT17 cells in the peripheral blood of patients with lung adenocarcinoma (LA) were higher than those in healthy controls (HCs), whereas the frequency of Tc17 cells in the patients with LA was decreased. In addition, the frequencies of circulating Th17 and γδT17 cells, but not Tc17 cells, were positively associated with tumor invasion and metastasis. Furthermore, the major source of IL-17A production was Th17 cells, followed by Tc17 and γδT17 cells, in peripheral blood from patients with LA and HCs; but the percentages of Th17 and γδT17 cells in total intracellular IL-17A⁺ cells obtained from the patients with LC were higher than those from HCs. Moreover, the protein and corresponding mRNA levels of IL-17A, IL-23, IL-1β, and TGF-β1 were much higher in the patients with LA than those in HCs, and the levels of IL-17A in patients were positively correlated with numbers of both Th17 and γδT17 cells, but not Tc17 cells. Finally, the frequencies of circulating Th17 and γδT17 cells, along with the levels of IL-17A, IL-23, IL-1β, and TGF-β1 were decreased in the patients with LA after tumor resection, whereas the frequency of circulating Tc17 cells was inversely increased in these patients. Our findings indicate that Th17, Tc17, γδT17 cells, and IL-17A-associated cytokines contribute to the development of LA and thus represent promising targets for therapeutic strategies.

Expression levels of IL-17 and TNF-α in degenerated lumbar intervertebral discs and their correlation

The present study aimed to investigate the expression and roles of interleukin (IL)-17 and tumor necrosis factor (TNF)-α in intervertebral disc degeneration (IDD) and to identify the association between the effects of IL-17 and TNF-α in IDD. This may increase understanding of the pathogenic mechanism underlying IDD, and aid the development of alternative therapies. The experimental group consisted of 40 samples of nucleus pulposus tissue obtained from the intervertebral discs (IVDs) of patients with IDD by surgical intervention, and was further divided into an annulus fibrosus disrupted group, comprising 18 patients in which the external annulus was ruptured, and an annulus fibrosus intact group comprising 22 patients. The control group consisted of 20 samples of nucleus pulposus tissue from the IVDs of patients with traumatic lumbar disc fractures. The mRNA and protein expression levels of IL-17 and TNF-α in the 50 tissue samples were detected by semi-quantitative reverse transcription polymerase chain reaction and immunohistochemical staining, respectively, and the results were statistically analyzed. The IL-17 and TNF-α protein and mRNA expression levels in the annulus fibrosus disrupted and annulus fibrosus intact groups were both higher compared with those in the control group. In addition, the expression levels of IL-17 and TNF-α in the annulus fibrosus disrupted group were significantly higher compared with those in the annulus fibrosus intact group (P<0.01). A positive correlation was identified between the mRNA and protein expression levels of IL-17 and TNF-α in the experimental group (r=0.957, P<0.01). IL-17 and TNF-α may therefore be involved in the progression of human IDD, and may have synergistic effects in the development of IDD.

IL-21 polymorphisms rs907715 and rs2221903 are associated with decreased non-small cell lung cancer susceptibility

The etiology of lung cancer is still incompletely understood. Previous studies have suggested the association between IL-21 polymorphisms and autoimmune diseases, however, little is known about its role in lung cancer susceptibility. Here, we investigated the role of two SNPs of IL-21 gene in a cohort of non-small cell lung cancer (NSCLC) patients. A total of 128 NSCLC patients and 156 healthy controls were genotyped. Multivariate logistic regression was used to analyze the association between IL-21 polymorphisms and NSCLC risk. Our data showed that both rs907715 and rs2221903 were significantly associated with lung cancer susceptibility, and patients carrying rs907715A (P = 0.007, adjusted OR = 0.60, 95% CI = 0.42-0.87) or rs2221903G (P = 0.020, adjusted OR = 0.52, 95% CI = 0.30-0.90) allele had a decreased risk of NSCLC. Further study identified that the association between IL-21 polymorphisms and NSCLC risk was limited to lung adenocarcinoma. Haplotype analysis revealed that the AG (P = 0.006, OR = 0.072 95% CI = 0.011-0.451) and AA (P = 0.022, OR = 0.657, 95% CI = 0.458-0.941) haplotypes of rs907715/rs2221903 were associated with a decreased risk of NSCLC, whereas the GA (P = 0.0001, OR = 1.932, 95% CI = 1.378-2.710) haplotype was associated with an increased risk. In conclusion, our study demonstrates the association between IL-21 polymorphisms (rs907715 and rs2221903) and NSCLC risk in a Chinese Han population, indicating their potential role in lung cancer detection and treatment.

IL-17A Promotes Intracellular Growth of Mycobacterium by Inhibiting Apoptosis of Infected Macrophages

The fate of infected macrophages is a critical aspect of immunity to mycobacteria. By depriving the pathogen of its intracellular niche, apoptotic death of the infected macrophage has been shown to be an important mechanism to control bacterial growth. Here, we show that IL-17 inhibits apoptosis of Mycobacterium bovis BCG- or Mycobacterium tuberculosis-infected macrophages thus hampering their ability to control bacterial growth. Mechanistically, we show that IL-17 inhibits p53, and impacts on the intrinsic apoptotic pathway, by increasing the Bcl2 and decreasing Bax expression, decreasing cytochrome c release from the mitochondria, and inhibiting caspase-3 activation. The same effect of IL-17 was observed in infected macrophages upon blockade of p53 nuclear translocation. These results reveal a previously unappreciated role for the IL-17/p53 axis in the regulation of mycobacteria-induced apoptosis and can have important implications in a broad spectrum of diseases where apoptosis of the infected cell is an important host defense mechanism.

Human colon carcinogenesis is associated with increased interleukin-17-driven inflammatory responses

Inflammation is known to contribute to carcinogenesis in human colorectal cancer. Proinflammatory cytokine interleukin-17 (IL-17 or IL-17A) has been shown to play a critical role in colon carcinogenesis in mouse models. However, few studies have investigated IL-17A in human colon tissues. In the present study, we assessed IL-17-driven inflammatory responses in 17 cases of human colon adenocarcinomas, 16 cases of human normal colon tissues adjacent to the resected colon adenocarcinomas, ten cases of human ulcerative colitis tissues from biopsies, and eight cases of human colon polyps diagnosed as benign adenomas. We found that human colon adenocarcinomas contained the highest levels of IL-17A cytokine, which was significantly higher than the IL-17A levels in the adenomas, ulcerative colitis, and normal colon tissues (P<0.01). The levels of IL-17 receptor A (IL-17RA) were also the highest in human colon adenocarcinomas, followed by adenomas and ulcerative colitis. The increased levels of IL-17A and IL-17RA were accompanied with increased IL-17-driven inflammatory responses, including activation of extracellular signal-regulated kinase (ERK)1/2 and c-Jun N-terminal kinase (JNK) pathways, increase in expression of matrix metalloproteinase (MMP)9, MMP7, MMP2, B-cell lymphoma (Bcl-2), and cyclin D1, decrease in Bcl-2-associated X protein (BAX) expression, and increase in vascular endothelial growth factor (VEGF) and VEGF receptor (VEGFR) expression that were associated with increased angiogenesis. These findings suggest that IL-17 and its signaling pathways appear as promising new targets in the design and development of drugs for cancer prevention and treatment, particularly in colorectal cancer.