Endometrial senescence is mediated by interleukin 17 receptor B signaling.

BACKGROUND: We previously identified Il17RB, a member of the IL17 superfamily, as a candidate marker gene for endometrial aging. While IL17RB has been linked to inflammation and malignancies in several organ systems, its function in the endometrium has not been investigated and is thus poorly understood. In the present study, we performed a functional analysis of this receptor with the aim of determining the effects of its age-associated overexpression on the uterine environment. METHODS: We analyzed IL17RB-related signaling pathways and downstream gene expression in an immortalized human endometrial glandular epithelial cell line ("hEM") forced to express the receptor via lentiviral transduction ("IL17RB-hEM"). We also prepared endometrial organoids from human endometrial tissue sourced from hysterectomy patients ("patient-derived EOs") and exposed them to cytokines that are upregulated by IL17RB expression to investigate changes in organoid-forming capacity and senescence markers. We analyzed RNA-seq data (GEO accession number GSE132886) from our previous study to identify the signaling pathways associated with altered IL17RB expression. We also analyzed the effects of the JNK pathway on organoid-forming capacity. RESULTS: Stimulation with interleukin 17B enhanced the NF-κB pathway in IL17RB-hEM, resulting in significantly elevated expression of the genes encoding the senescence associated secretory phenotype (SASP) factors IL6, IL8, and IL1ß. Of these cytokines, IL1ß inhibited endometrial organoid growth. Bioinformatics analysis showed that the JNK signaling pathway was associated with age-related variation in IL17RB expression. When IL17RB-positive cells were cultured in the presence of IL17B, their organoid-forming capacity was slightly but non-significantly lower than in unexposed IL17RB-positive cells, but when IL17B was paired with a JNK inhibitor (SP600125), it was restored to control levels. Further, IL1ß exposure significantly reduced organoid-forming capacity and increased p21 expression in endometrial organoids relative to non-exposure (control), but when IL1ß was paired with SP600125, both indicators were restored to levels comparable to the control condition. CONCLUSIONS: We have revealed an association between IL17RB, whose expression increases in the endometrial glandular epithelium with advancing age, and cellular senescence. Using human endometrial organoids as in vitro model, we found that IL1ß inhibits cell proliferation and leads to endometrial senescence via the JNK pathway.

IL17RB genetic variants are associated with acamprosate treatment response in patients with alcohol use disorder: A proteomics-informed genomics study.

Acamprosate is a Food and Drug Administration (FDA) approved medication for the treatment of alcohol use disorder (AUD). However, only a subset of patients achieves optimal treatment outcomes. Currently, no biological measures are utilized to predict response to acamprosate treatment. We applied our established pharmaco-omics informed genomics strategy to identify potential biomarkers associated with acamprosate treatment response. Specifically, our previous open-label acamprosate clinical trial recruited 442 patients with AUD who were treated with acamprosate for three months. We first performed proteomics using baseline plasma samples to identify potential biomarkers associated with acamprosate treatment outcomes. Next, we applied our established "proteomics-informed genome-wide association study (GWAS)" research strategy, and identified 12 proteins, including interleukin-17 receptor B (IL17RB), associated with acamprosate treatment response.​ A GWAS for IL17RB concentrations identified several genome-wide significant signals. Specifically, the top hit single nucleotide polymorphism (SNP) rs6801605 with a minor allele frequency of 38% in the European American population mapped 4 kilobase (Kb) upstream of IL17RB, and intron 1 of the choline dehydrogenase (CHDH) gene on chromosome 3 (p: 4.8E-20). The variant genotype (AA) for the SNP rs6801605 was associated with lower IL17RB protein expression. In addition, we identified a series of genetic variants in IL17RB that were associated with acamprosate treatment outcomes. Furthermore, the variantgenotypes for all of those IL17RB SNPs were protective for alcohol relapse. Finally, we demonstrated that the basal level of mRNA expression of IL17RB was inversely correlated with those of nuclear factor-κB (NF-κB) subunits, and a significantly higher expression of NF-κB subunits was observed in AUD patients who relapsed to alcohol use. In summary, this study illustrates that IL17RB genetic variants might contribute to acamprosate treatment outcomes. This series of studies represents an important step toward generating functional hypotheses that could be tested to gain insight into mechanisms underlying acamprosate treatment response phenotypes. (The ClinicalTrials.gov Identifier: NCT00662571).

IL25+ macrophages are a key determinant of treatment resistance of IL17RB+ breast cancer.

Recurrence and metastasis are resistant to multimodal treatments, and are the major causes of death in breast cancer. Accumulating evidence suggests that the IL17RB signaling pathway plays a key role in progression and metastasis of breast cancer. Clinical significance of the IL17RB positivity in tumor tissues has been also reported as a poor prognostic factor in breast cancer. However, the molecular mechanisms underlying the poor prognosis of patients with IL17RB+ breast cancer, particularly the immunological aspects, remain to be fully elucidated, and elimination of the IL17RB+ tumors has not been practically achieved in clinical settings. In this study, we identified a distinct molecular mechanism underlying the intractability of the IL17RB+ tumors through tumor biological and immunological investigation using mouse and human breast cancer cells transduced with il17rb gene. IL17RB overexpression in tumor cells confers cancer stemness, including high invasive and self-renewal abilities, and high resistance to CDK4/6 inhibitors that have been considered as a promising agent for treating breast cancer despite the limited efficacy. In the mice implanted with the IL17RB+ tumors, IL25+ macrophages (Møs) are expanded locally in tumor tissues and systemically in spleen, and promote the IL17RB+ tumor progression directly by intensifying the tumor functions, and indirectly via impairment of anti-tumor effector CTLs and NK cells utilizing the secreted IL25. Blocking IL25 with the specific mAb, however, interferes the adverse events, and successfully elicits significant anti-tumor efficacy in combination with CDK4/6 inhibitors providing better survival in murine mammary tumor models. These results suggest that the IL25+ Mø is a key determinant of building the solid treatment resistance of the IL17RB+ breast cancer. Targeting the IL17RB-IL25 axis may be a promising strategy to improve clinical outcomes in the treatment of breast cancer patients, particularly with IL17RB+ tumors.

IL17RB expression is associated with malignant cancer behaviors and poor prognosis in oral cancer.

OBJECTIVES: Previously, we demonstrated that IL17RB plays an essential role in lung cancer progression. This study aimed to determine whether IL17RB correlates with oral cancer and promotes oral cancer progression. SUBJECTS AND METHODS: IL17RB expression in oral cancer tissues and normal tissues was determined by immunohistochemistry staining, while the association of IL17RB expression with the clinicopathological characteristics of oral squamous cell carcinoma (OSCC) patients was analyzed and its correlation with progression-free survival and response to radiotherapy and chemotherapy in OSCC patients was also explored. Western blotting was performed to investigate the expression of IL17RB in various OSCC cell lines; moreover, transwell assay was performed to evaluate the effect of IL17RB expression on cell migration ability. RESULTS: In this study, we found that IL17RB was expressed higher in OSCC tissues compared to normal oral mucosa tissues and its expression was positively correlated with tumor size, lymph node metastasis, advanced cancer stage, and poor prognosis. In vitro study showed that IL17RB expression in OSCC cell lines as determined by Western blotting, was positively correlated with their migration ability. CONCLUSION: Clinical and in vitro studies suggest that IL17RB might serve as an independent risk factor and a therapeutic target for oral cancer.

CINC-2 and miR-199a-5p in EVs secreted by transplanted Thy1+ cells activate hepatocytic progenitor cell growth in rat liver regeneration.

BACKGROUND: Small hepatocyte-like progenitor cells (SHPCs) are hepatocytic progenitor cells that transiently form clusters in rat livers treated with retrorsine (Ret) that underwent 70% partial hepatectomy (PH). We previously reported that transplantation of Thy1+ cells obtained from D-galactosamine-treated livers promotes SHPC expansion, thereby accelerating liver regeneration. Extracellular vesicles (EVs) secreted by Thy1+ cells induce sinusoidal endothelial cells (SECs) and Kupffer cells (KCs) to secrete IL17B and IL25, respectively, thereby activating SHPCs through IL17 receptor B (RB) signaling. This study aimed to identify the inducers of IL17RB signaling and growth factors for SHPC proliferation in EVs secreted by Thy1+ cells (Thy1-EVs). METHODS: Thy1+ cells isolated from the livers of rats treated with D-galactosamine were cultured. Although some liver stem/progenitor cells (LSPCs) proliferated to form colonies, others remained as mesenchymal cells (MCs). Thy1-MCs or Thy1-LSPCs were transplanted into Ret/PH-treated livers to examine their effects on SHPCs. EVs were isolated from the conditioned medium (CM) of Thy1-MCs and Thy1-LSPCs. Small hepatocytes (SHs) isolated from adult rat livers were used to identify factors regulating cell growth in Thy1-EVs. RESULTS: The size of SHPC clusters transplanted with Thy1-MCs was significantly larger than that of SHPC clusters transplanted with Thy1-LSPCs (p = 0.02). A comprehensive analysis of Thy1-MC-EVs revealed that miR-199a-5p, cytokine-induced neutrophil chemoattractant-2 (CINC-2), and monocyte chemotactic protein 1 (MCP-1) were candidates for promoting SHPC growth. Additionally, miR-199a-5p mimics promoted the growth of SHs (p = 0.02), whereas CINC-2 and MCP-1 did not. SECs treated with CINC-2 induced Il17b expression. KCs treated with Thy1-EVs induced the expression of CINC-2, Il25, and miR-199a-5p. CM derived from SECs treated with CINC-2 accelerated the growth of SHs (p = 0.03). Similarly, CM derived from KCs treated with Thy1-EVs and miR-199a-5p mimics accelerated the growth of SHs (p = 0.007). In addition, although miR-199a-overexpressing EVs could not enhance SHPC proliferation, transplantation of miR-199a-overexpressing Thy1-MCs could promote the expansion of SHPC clusters. CONCLUSION: Thy1-MC transplantation may accelerate liver regeneration owing to SHPC expansion, which is induced by CINC-2/IL17RB signaling and miR-199a-5p via SEC and KC activation.

IL17RB and IL17REL Expression Are Associated with Improved Prognosis in HPV-Infected Head and Neck Squamous Cell Carcinomas.

Changes in the cellular secretome are implicated in virus infection, malignancy, and anti-tumor immunity. We analyzed the association between transcriptional signatures (TS) from 24 different immune and stromal cell types on the prognosis of HPV-infected and HPV-free head and neck squamous carcinoma (HNSCC) patients from The Cancer Genome Atlas (TCGA) cohort. We found that HPV-positive HNSCC patients have tumors with elevated immune cell TS and improved prognosis, which was specifically associated with an increased tumor abundance of memory B and activated natural killer (NK) cell TS, compared to HPV-free HNSCC patients. HPV-infected patients upregulated many transcripts encoding secreted factors, such as growth factors, hormones, chemokines and cytokines, and their cognate receptors. Analysis of secretome transcripts and cognate receptors revealed that tumor expression of IL17RB and IL17REL are associated with a higher viral load and memory B and activated NK cell TS, as well as improved prognosis in HPV-infected HNSCC patients. The transcriptional parameters that we describe may be optimized to improve prognosis and risk stratification in the clinic and provide insights into gene and cellular targets that may potentially enhance anti-tumor immunity mediated by NK cells and memory B cells in HPV-infected HNSCC patients.

Chronic allergic asthma alters m6A epitranscriptomic tagging of mRNAs and lncRNAs in the lung.

To evaluate the role of m6A methylation of mRNAs and long non-coding RNAs (lncRNAs) in chronic allergic asthma. Transcriptome-wide N6-methyladenosine (m6A) changes in BALB/c mice were profiled using immunoprecipitated methylated RNAs with microarrays in lung with chronic allergic asthma. Gene ontology (GO) and KEGG analyses were conducted. Target genes were verified by methylated RNA immunoprecipitation and real-time polymerase chain reaction (PCR). Specifically, the mRNA levels of m6A writers (METTL3, METTL14, and WTAP), and readers and erasers (FTO and ALKBH5) were estimated by real-time PCR analysis, using the SYBR-green method. IL17RB mRNA was also evaluated by PCR. Hematoxylin and eosin (H&E) staining showed that the airway and lung tissues in mice in the asthma group had extensive infiltration of inflammatory cells around the bronchioles, blood vessels, and alveoli. The lungs of those allergic asthma mice showed altered m6A epitranscriptome, whereby 1369 mRNAs and 176 lncRNAs were hypermethylated, and 197 mRNAs and 30 lncRNAs were hypomethylated (>1.5-fold vs control). Also, compared with the control group, IL17RB mRNA in lung of the asthmatic group was significantly hypermethylated (P<0.01). In the asthma group, the mRNA and the protein level of METTL14 (the key methyltransferase) and ALKBH5 (the major demethyltransferase) were significantly decreased compared with the control group (P<0.01). Chronic allergic asthma alters the lung m6A epitranscriptome, suggesting functional implications in the pathophysiology of refractory asthma. Data support methylated IL17RB mRNA possibly becoming a new therapeutic target for chronic allergic asthma.

Structural basis of interleukin-17B receptor in complex with a neutralizing antibody for guiding humanization and affinity maturation.

Upregulation of interleukin-17 receptor B (IL-17RB) is known to be oncogenic, while other IL-17 receptors and ligands are generally involved in pro-inflammatory pathways. We identify a mouse neutralizing monoclonal antibody (mAb) D9, which blocks the IL-17RB/IL-17B pathway and inhibits pancreatic tumorigenesis in an orthotopic mouse model. The X-ray crystal structure of the IL-17RB ectodomain in complex with its neutralizing antibody D9 shows that D9 binds to a predicted ligand binding interface and engages with the A'-A loop of IL-17RB fibronectin III domain 1 in a unique conformational state. This structure also provides important paratope information to guide the design of antibody humanization and affinity maturation of D9, resulting in a humanized 1B12 antibody with marginal affinity loss and effective neutralization of IL-17B/IL-17RB signaling to impede tumorigenesis in a mouse xenograft model.

IL-25 directly modulates adipocyte function and inflammation through the regulation of adiponectin.

OBJECTIVE: This study aimed to investigate the direct role of IL-25 in modulating adipocyte function during homeostasis and low-grade inflammation induced by lipopolysaccharide (LPS). METHODS: The 3T3-L1 preadipocyte cell lines and primary cultures of adipose-derived stromal vascular precursor cells of wild-type and IL-17RB-deficient mice were used to determine the direct function of IL-25. The expression of IL-17RB in differentiating adipocyte was determined using real-time PCR and flow cytometry analysis. The effect of IL-25 on lipid accumulation, triglyceride content, lipolysis, glucose uptake, and adipokine expression in the mature adipocytes was evaluated. IL-25 modulating the expression of inflammatory cytokines in adipocytes induced by low dose LPS was determined using real-time PCR and ELISA. RESULTS: The receptor for IL-25 was up-regulated during adipocyte differentiation and IL-25 directly modulated adipocyte function by reducing lipid accumulation and triglyceride concentration and enhancing lipolysis without affecting an insulin-stimulated glucose uptake. Interestingly, IL-25 induced adiponectin secretion through the PI3K/AKT signaling pathway. In 3T3-L1 adipocytes under low-grade inflammation, IL-25 attenuated the expression of IL-6 and CCL5 through the induction of adiponectin. CONCLUSION: Our studies suggest that IL-25 directly regulates adipocyte function by maintaining the adiponectin level during homeostasis and by alleviating inflammatory response through the regulation of adiponectin during low-grade inflammation in adipocytes.

Active Humoral Response Reverts Tumorigenicity through Disruption of Key Signaling Pathway.

Immune checkpoint inhibitors such as monoclonal antibodies (mAbs) are amongst the most important breakthroughs in cancer therapeutics. However, high cost and short acting time limits its affordability and clinical application. Therefore, an economical and durable alternative is urgently needed. Previously, we identified an IL-17RB targeting mAb which intercepts IL-17B/IL-17RB signal transduction and suppresses tumorigenesis in many types of cancer. We reason that active immunity against the antigenic epitope of IL-17RB can reproduce the anti-cancer effect of mAbs with better sustainability. Here, we present a cancer vaccine composed of multiple synthesized epitope peptides chemically conjugated onto CRM197, a highly immunogenic carrier protein. Combining mass spectrometry with immunoassay, we standardized hapten density determination and optimized vaccine design. Furthermore, orthotopically transplanted syngeneic mouse tumor 4T1 showed that administration of this vaccine therapeutically mitigates primary cancer growth as well as distance metastasis. In conclusion, we demonstrate preparation, characterization and pre-clinical application of a novel peptide cancer vaccine.

Interleukin-25-Mediated-IL-17RB Upregulation Promotes Cutaneous Wound Healing in Diabetic Mice by Improving Endothelial Cell Functions.

Diabetic foot ulcer (DFU) frequently leads to non-traumatic amputation and finally even death. However, the mechanism of DFU is not fully understood. Interleukin 25 (IL-25), an alarmin cytokine that responds to tissue injury, has been reported to participate in tissue regeneration and maintaining glucose homeostasis. However, the role of IL-25 in diabetic wound healing remains unknown. Here, we showed that interleukin 17 receptor B (IL-17RB), the functional receptor of IL-25, was significantly inhibited in the wound skin of both diabetic patients with DFU and streptozotocin (STZ)-induced diabetic mice. Topical administration of recombinant IL-25 protein improved angiogenesis and collagen deposition in the wound bed and thus ameliorated delayed diabetic wound healing. IL-25 increased endothelial-specific CD31 expression in diabetic wounds and exogenous IL-25 protected endothelial cells from high glucose-impaired cell migration and tube formation in vitro. We further revealed that IL-25-mediated-IL-17RB signaling rescued the downregulation of Wnt/ß-catenin pathway both in vivo in diabetic mice and in vitro in HUVECs and induced the phosphorylation of AKT and ERK 1/2 in HUVECs under high glucose conditions. This study defines a positive regulatory role of IL-25-mediated-IL-17RB signaling in diabetic wound healing and suggests that induction of IL-25-mediated-IL-17RB signaling may be a novel therapeutic strategy for treating poor healing diabetic wounds.

Interleukin-25 recognition by its unique receptor IL-17Rb via two discrete linear and cyclic epitopes.

Interleukin-17 (IL-17) is a family of pro-inflammatory cytokines and has been involved in the pathogenesis of chronic inflammatory and autoimmune diseases. The IL-17E, also known as IL-25, is a distinct member of this family that binds to its unique receptor IL-17Rb to induce the activation of nuclear factor kappa-light-chain enhancer of activated B cells. Here, we systematically examined the intermolecular recognition and association of IL-25 with IL-17Rb and demonstrated that the IL-25 primarily adopts two discrete linear and cyclic epitopes to interact with IL-17Rb. The two epitopes are separately located in the monomers 1 and 2 of IL-25 homodimer and cover sequences 125 DPRGNSELLYHN136 and 77 ELDRDLNRLPQDLY90 . They totally contribute 71.6% binding energy to the full-length IL-25. The linear epitope targets a site spanning over the extracellular fnIIID1 and fnIIID2 domains of IL-17Rb, while the cyclic epitope primarily binds at the fnIIID1 domain. In addition, we also found that the linear and cyclic epitopes are natively folded into ordered single-stranded and double-stranded conformations in IL-25 protein context, respectively, but would become largely disordered when splitting from the context to be free peptides, which, however, cannot bind effectively to IL-17Rb as them in the native state. In this respect, we extended the cyclic epitope to cover the whole IL-25 double-stranded region and added a disulfide bridge across its two strands at three selected anchor residue pairs. It is revealed that the disulfide-stapled peptides can be constrained into a native-like conformation and thus exhibit an improved binding potency to IL-17Rb as compared to their unstapled counterpart.

The significance of HOXB7 and IL17RB serum levels in prognosis of hormonally dependent breast cancer: A pilot study.

PURPOSE: Improved prognostication of a patient's outcome could allow for personalized treatment decisions in breast cancer. Homeobox B7 (HOXB7) and interleukin 17 receptor B (IL17RB) are proteins reportedly involved in the development of hormonal therapy resistance. Their prognostic value was previously investigated in tumor tissue but recent mass spectrometric detection of HOXB7 and IL17RB proteins in serum has prompted us to perform the first prognostic evaluation of their serum levels. PATIENTS AND METHODS: The study included 81 premenopausal breast cancer patients that received adjuvant hormonal therapy. The median follow-up period was 61 months. HOXB7 and IL17RB serum protein levels were measured by quantitative sandwich ELISA and prognostically evaluated by Cox proportional hazards regression analysis. RESULTS: HOXB7 protein was detected in 96.3% and IL17RB in 33.3% of serum samples. Higher levels of serum HOXB7 significantly associated with favorable disease outcome by prognosticating distant (by HR â€‹= â€‹0.04; P â€‹= â€‹0.001) and local recurrence (by HR â€‹= â€‹0.03, P â€‹= â€‹0.001). The recurrence rates in the HOXB7high and HOXB7low subgroups of patients (cut-off 81.5 â€‹pg/mL) were 0% and 17%, respectively. Serum IL17RB levels did not significantly associate with either local or distant events. The multivariate analysis highlighted estrogen receptor, histological grade, nodal status and HOXB7 as independent prognostic parameters. CONCLUSIONS: Our findings validate the previous mass-spectrometry data by showing that HOXB7 and IL17RB cellular proteins are detectable in serum by a standard ELISA assay. Furthermore, we show that HOXB7 serum levels are the relevant prognosticator of response to hormonal therapy.

Identification of genes associated with endometrial cell ageing.

Ageing of the uterine endometrium is a critical factor that affects reproductive success, but the mechanisms associated with uterine ageing are unclear. In this study, we conducted a qualitative examination of age-related changes in endometrial tissues and identified candidate genes as markers for uterine ageing. Gene expression patterns were assessed by two RNA-sequencing experiments using uterine tissues from wild type (WT) C57BL/6 mice. Gene expression data obtained by RNA-sequencing were validated by real-time PCR. Genes expressing the pro-inflammatory cytokines Il17rb and chemokines Cxcl12 and Cxcl14 showed differential expression between aged WT mice and a group of mice composed of 5- and 8-week-old WT (young) animals. Protein expression levels of the above-mentioned genes and of IL8, which functions downstream of IL17RB, were analysed by quantitative immunohistochemistry of unaffected human endometrium tissue samples from patients in their 20s and 40s (10 cases each). In the secretory phase samples, 3,3'- diaminobenzidine staining intensities of IL17RB, CXCL12 and CXCL14 for patients in their 40s were significantly higher than that for patients in their 20s, as detected by a Mann-hitney U test. These results suggest that these genes are candidate markers for endometrial ageing and for prediction of age-related infertility, although confirmation of these findings is needed in larger studies involving fertile and infertile women.

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.

IL17RB expression might predict prognosis and benefit from gemcitabine in patients with resectable pancreatic cancer.

BACKGROUND: (Interleukin 17 Receptor Beta) IL17RB has been implicated in several malignancies. However, its role in the progression of and chemosensitivity in pancreatic cancer remains unknown. We aimed to determine the clinical significance of IL17RB expression in the prognosis of resectable pancreatic cancer and in the benefits from gemcitabine treatment. MATERIALS AND METHODS: We used microarray and immunohistochemical staining techniques to evaluate IL17RB expression in 91 resectable pancreatic cancer tissues and their respective matched adjacent non-cancerous tissues. Quantitative real-time PCR and Western blotting were used to evaluate IL17RB in human pancreatic cancer cell lines after gemcitabine treatment. The correlation between IL17RB expression and overall survival and disease-free survival times were analyzed. RESULTS: IL17RB expression correlated with lymph node metastasis and (Vascular endothelial growth factor) VEGF expression. Cox proportional model showed that high IL17RB expression is a significant negative prognostic factor for both (overall survival) OS and (disease-free survival) DFS. Kaplan-Meier survival curves confirmed significantly reduced median overall and DFS time in high IL17RB patients as compared with low IL17RB patients. Furthermore, Cox proportional model confirmed a correlation between adjuvant treatment with gemcitabine-based chemotherapy and IL17RB expression. Kaplan-Meier survival curves showed that low IL17RB expression was associated with longer OS and DFS in patients than high IL17RB expression and gemcitabine-based adjuvant chemotherapy. In human pancreatic cancer cell lines, the messenger RNA and protein levels of IL17RB were significantly enhanced after gemcitabine treatment. CONCLUSIONS: IL17RB predicts the prognosis and benefit from gemcitabine in patients with resectable pancreatic cancer.

Lineage tracing and targeting of IL17RB+ tuft cell-like human colorectal cancer stem cells.

Cancer stem cell (CSC)-specific markers may be potential therapeutic targets. We previously identified that Dclk1, a tuft cell marker, marks tumor stem cells (TSCs) in mouse intestinal adenomas. Based on the analysis of mouse Dclk1+ tumor cells, we aimed to identify a CSC-specific cell surface marker in human colorectal cancers (hCRCs) and validate the therapeutic effect of targeting it. IL17RB was distinctively expressed by Dclk1+ mouse intestinal tumor cells. Using Il17rb-CreERT2-IRES-EGFP mice, we show that IL17RB marked intestinal TSCs in an IL13-dependent manner. Tuft cell-like cancer cells were detected in a subset of hCRCs. In these hCRCs, lineage-tracing experiments in CRISPR-Cas9-mediated IL17RB-CreERT2 knockin organoids and xenograft tumors revealed that IL17RB marks CSCs that expand independently of IL-13. We observed up-regulation of POU2F3, a master regulator of tuft cell differentiation, and autonomous tuft cell-like cancer cell differentiation in the hCRCs. Furthermore, long-term ablation of IL17RB-expressing CSCs strongly suppressed the tumor growth in vivo. These findings reveal insights into a CSC-specific marker IL17RB in a subset of hCRCs, and preclinically validate IL17RB+ CSCs as a cancer therapeutic target.

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.

Blockade of RGMb inhibits allergen-induced airways disease.

BACKGROUND: Allergic asthma causes morbidity in many subjects, and novel precision-directed treatments would be valuable. OBJECTIVE: We sought to examine the role of a novel innate molecule, repulsive guidance molecule b (RGMb), in murine models of allergic asthma. METHODS: In models of allergic asthma using ovalbumin or cockroach allergen, mice were treated with anti-RGMb or control mAb and examined for airway inflammation and airway hyperreactivity (AHR), a cardinal feature of asthma. The mechanisms by which RGMb causes airways disease were also examined. RESULTS: We found that blockade of RGMb by treatment with anti-RGMb mAb effectively blocked the development of airway inflammation and AHR. Importantly, blockade of RGMb completely blocked the development of airway inflammation and AHR, even if treatment occurred only during the challenge (effector) phase. IL-25 played an important role in these models of asthma because IL-25 receptor-deficient mice did not develop disease after sensitization and challenge with allergen. RGMb was expressed primarily by innate cells in the lungs, including bronchial epithelial cells (known producers of IL-25), activated eosinophils, and interstitial macrophages, which in the inflamed lung expressed the IL-25 receptor and produced IL-5 and IL-13. We also found that neogenin, the canonical receptor for RGMb, was expressed by interstitial macrophages and bronchial epithelial cells in the inflamed lung, suggesting that an innate RGMb-neogenin axis might modulate allergic asthma. CONCLUSIONS: These results demonstrate an important role for a novel innate pathway in regulating type 2 inflammation in patients with allergic asthma involving RGMb and RGMb-expressing cells, such as interstitial macrophages and bronchial epithelial cells. Moreover, targeting this previously unappreciated innate pathway might provide an important treatment option for allergic asthma.

A positive feedback loop of IL-17B-IL-17RB activates ERK/ß-catenin to promote lung cancer metastasis.

Inflammation contributes to the development and progression of cancer. Interleukin-17 (IL-17) is an inflammatory cytokine that functions in inflammation and cancer, as well as several other cellular processes. In this study, we investigated the roles and the prognostic value of IL-17 and the IL-17 receptor (IL-17R) in lung cancer. Gene expression microarray analysis followed by Kaplan-Meier survival curve showed that IL-17B was associated with poor patient survival, and IL-17B receptor (IL-17RB) was up-regulated in lung cancer tissue compared with normal tissue. Expression of IL-17RB was associated with lymph node metastasis and distant metastasis, as well as poor patient survival. IL-17RB overexpression significantly increased cancer cell invasion/migration and metastasis in vitro and in vivo. IL-17RB induced ERK phosphorylation, resulting in GSK3ß inactivation and leading to ß-catenin up-regulation. IL-17RB also participated in IL-17B synthesis via the ERK pathway. IL-17RB activation is required for IL-17B-mediated ERK phosphorylation. Taken together, IL-17B-IL-17RB signaling and ERK participate in a positive feedback loop that enhances invasion/migration ability in lung cancer cell lines. IL-17RB may therefore serve as an independent prognostic factor and a therapeutic target for lung cancer.