M2 macrophage-related gene signature in chronic rhinosinusitis with nasal polyps

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a common sinonasal inflammatory disorder with high heterogeneity. Increasing evidence have indicated that the infiltration of macrophages especially M2 macrophages play pivotal roles in the pathogenesis of CRSwNP, but the underlying mechanisms remain undetermined. This study sought to identify potential biomarkers related to M2 macrophages in CRSwNP.

METHODS

The expression datasets of GSE136825 and GSE179265 were download from Gene Expression Omnibus (GEO) database and merged. Then, CIBERSORT and weighted gene co-expression network analysis (WGCNA) algorithms were applied to identify M2 macrophage-related gene modules. Thereafter, differentially expressed genes (DEGs) related to M2 macrophages were selected to perform functional enrichment analyses. A protein-protein interaction (PPI) network was built to identify hub genes and quantitative real-time reverse transcriptions PCR was used to verify the bioinformatics results.

RESULTS

A total of 92 DEGs associated with M2 macrophages were identified for further analysis. The results of Gene ontology (GO) and Kyoto Encyclopedia of genes and genomes (KEGG) analyses illustrated that M2 macrophage-associated DEGs primarily enriched in immune responses and extracellular matrix structure. PPI network analysis identified 18 hub genes related to M2 macrophages that might be pivotal in the pathogenesis of CRSwNP. After verification, AIF1, C1QA, C1QB, C3AR1, CCR1, CD163, CD4, CD53, CD86, CSF1R, CYBB, FCER1G, FCGR3A, IL10RA, ITGB2, LAPTM5, PLEK, TYROBP were identified as potential M2 macrophage-related biomarkers for CRSwNP.

CONCLUSION

These findings yield new insights into the hub genes and mechanisms related to M2 macrophages in the pathogenesis of CRSwNP. Further studies of these hub genes would help better understand the disease progression and identify potential treatment targets.

Identification of key genes and pathways in chronic rhinosinusitis with nasal polyps and asthma comorbidity using bioinformatics approaches

Patients with chronic rhinosinusitis with nasal polyps (CRSwNP) and asthma comorbidity (ACRSwNP) present severe symptoms and are more likely to relapse. However, the pathogenesis of ACRSwNP is not fully understood. The aim of this study was to explore the underlying pathogenesis of ACRSwNP using bioinformatics approaches. ACRSwNP-related differentially expressed genes (DEGs) were identified by the analysis of the GSE23552 dataset. The clusterProfiler R package was used to carry out functional and pathway enrichment analysis. A protein–protein interaction (PPI) network was built using the STRING database to explore key genes in the pathogenesis of ACRSwNP. The bioinformatics analysis results were verified through qRT-PCR. The Connectivity Map (CMap) database was used to predict potential drugs for the treatment of ACRSwNP. A total of 36 DEGs were identified, which were mainly enriched in terms of regulation of immune response and detection sensory perception of taste. Thirteen hub genes including AZGP1, AQP9, GAPT, PIP, and PRR4 were identified as potential hub genes in ACRSwNP from the PPI network. Analysis of the GSE41861 dataset showed that upregulation of CST1 in nasal mucosa was associated with asthma. qRT-PCR detection confirmed the bioinformatics analysis results. Tacrolimus and spaglumic acid were identified as potential drugs for the treatment of ACRSwNP from the CMap database. The findings of this study provide insights into the pathogenesis of ACRSwNP and may provide a basis for the discovery of effective therapeutic modalities for ACRSwNP.

TAS2R38 Bitter Taste Receptor Expression in Chronic Rhinosinusitis with Nasal Polyps: New Data on Polypoid Tissue

Studies have shown differences in TAS2R38 receptor expression in patients with chronic rhinosinusitis (CRS) compared to healthy controls. Known agonists of TAS2R38 stimulate epithelial cells, leading to robust intracellular nitric oxide (NO) production, which damages bacterial membranes, enzymes, and DNA, but also increases ciliary beat frequency. In this study we examined, using qRT-PCR, the expression of TAS2R38 receptor in nasal polyps (NP) of patients with CRS (N = 107) and in inferior turbinate mucosa (ITM) of patients with CRS and controls (N = 39), and confronted it with clinical features and the severity of the disease. The expression was shown in 43 (50.00%) samples of ITM in the study group (N = 107), in 28 (71.79%) in the control group (N = 39) (p = 0.037), and in 43 (46.24%) of NP. There were no differences in levels of the expression in all analyzed tissues. Patients who rated their symptoms at 0–3 showed higher TAS2R38 expression in ITM in comparison to the patients with 8–10 points on the VAS scale (p = 0.020). A noticeable, however not significant, correlation between the TAS2R38 expression in ITM and the Lund–Mackay CT score was shown (p = 0.068; R = −0.28). Patients with coexisting asthma had significantly higher receptor expression in the NP (p = 0.012). Our study is the first to confirm the presence of the TAS2R38 receptor in NP. Expression of the TAS2R38 receptor is reduced in the sinonasal mucosa in patients with more advanced CRS with NP.

Oncostatin M Counteracts the Fibrotic Effects of TGF-β1 and IL-4 on Nasal-Polyp-Derived Fibroblasts: A Control of Fibrosis in Chronic Rhinosinusitis with Nasal Polyps?

Chronic rhinosinusitis with nasal polyps (CRSwNP) is associated with inflammation and tissue remodeling including myofibroblasts differentiation and extracellular matrix (ECM) deposition mediated by TGF-β1 and IL-4. Oncostatin M (OSM) is a cytokine involved in fibrotic processes in other cellular subtypes. We investigated the mechanisms of action of OSM in the fibrosis process associated with CRSwNP. The expression of IL-4, OSM and TGF-β1 was assessed by RT-qPCR. Primary human cultures of nasal-polyp-derived fibroblasts were established and stimulated by TGF-β1 and/or IL-4 and/or OSM. The expression of ECM components and αSMA was determined by RT-qPCR and Western blot. TGF-β1-Smad3 signaling was investigated by immunofluorescence. TGF-β1, IL-4 and OSM as well as αSMA were overexpressed in nasal polyps when compared to noninflammatory nasal mucosa. In TGF-β1-stimulated nasal-polyp-derived fibroblasts, ECM genes and αSMA gene and protein were overexpressed, as well as αSMA in IL-4-stimulated fibroblasts. OSM counteracted the profibrotic effect of TGF-β1 on ECM components and αSMA. TGF-β1-induced nuclear translocation of Smad3 was completely reversed by OSM. OSM counteracts the profibrotic effect of IL-4 and also TGF-β1, by inhibiting the nuclear translocation of Smad3. We suggest OSM could be an efficient tool to protect against fibrosis in CRSwNP.

Type 2 and Type 17 Invariant Natural Killer T Cells Contribute to Local Eosinophilic and Neutrophilic Inflammation and Their Function Is Regulated by Mucosal Microenvironment in Nasal Polyps

Chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by heterogeneous inflammatory endotypes of unknown etiology. Invariant natural killer T (iNKT) cells are multifunctional innate T cells that exhibit Th1-, Th2-, and Th17-like characteristics. We investigated functional relationships between iNKT cells and inflammatory subtypes of CRSwNP. Eighty patients with CRSwNP and thirty-two control subjects were recruited in this study. Flow cytometry was used to analyze the frequencies and functions of iNKT cells and their subsets in peripheral blood mononuclear cells (PBMCs) and tissues. Polyp tissue homogenates were used to study the multifunctionality of iNKT cells. iNKT cells were significantly increased in polyps (0.41%) than in control mucosa (0.12%). iNKT cells were determined in the paucigranunlocytic (n=20), eosinophilic (n=22), neutrophilic (n=23), and mixed granulocytic (n=13) phenotypes of CRSwNP. The percentages of iNKT cells and HLA-DR⁺PD-1⁺ subsets were lower in eosinophilic or mixed granulocytic polyps than those of other phenotypes. iNKT cells and subsets were enriched in polyp tissues than in matched PBMCs. The evaluation of surface markers, transcription factors, and signature cytokines indicated that the frequencies of iNKT2 and iNKT17 subsets were significantly increased in eosinophilic and neutrophilic polyps, respectively, than in the paucigranulocytic group. Moreover, the production of type 2 (partially dependent on IL-7) and type 17 (partially dependent on IL-23) iNKT cells could be stimulated by eosinophilic and neutrophilic homogenates, respectively. Our study revealed that type 2 and type 17 iNKT cells were involved in eosinophilic and neutrophilic inflammation, respectively, in CRSwNP, while different inflammatory microenvironments could modulate the functions of iNKT cells, suggesting a role of iNKT cells in feedback mechanisms and local inflammation.

Expression of Oxidative Stress and Inflammation-Related Genes in Nasal Mucosa and Nasal Polyps from Patients with Chronic Rhinosinusitis

Chronic rhinosinusitis (CRS) is a prevalent, multifaceted inflammatory condition affecting the nasal cavity and the paranasal sinuses, frequently accompanied by formation of nasal polyps (CRSwNP). This apparently uniform clinical entity is preceded by heterogeneous changes in cellular and molecular patterns, suggesting the presence of multiple CRS endotypes and a diverse etiology. Alterations of the upper airway innate defense mechanisms, including antimicrobial and antioxidant capacity, have been implicated in CRSwNP etiology. The aim of this study was to investigate mRNA expression patterns of antioxidative enzymes, including superoxide dismutase (SOD) and peroxiredoxin-2 (PRDX2), and innate immune system defense players, namely the bactericidal/permeability-increasing fold-containing family A, member 1 (BPIFA1) and PACAP family members, particularly adenylate-cyclase-activating polypeptide receptor 1 (ADCYAP1) in nasal mucosa and nasal polyps from CRSwNP patients. Additional stratification based on age, sex, allergic comorbidity, and disease severity was applied. The results showed that ADCYAP1, BPIFA1, and PRDX2 transcripts are differentially expressed in nasal mucosa and scale with radiologically assessed disease severity in CRSwNP patients. Sinonasal transcriptome is not associated with age, sex, and smoking in CRSwNP. Surgical and postoperative corticosteroid (CS) therapy improves endoscopic appearance of the mucosa, but variably reverses target gene expression patterns in the nasal cavity of CRSwNP patients. Transcriptional cross-correlations analysis revealed an increased level of connectedness among differentially expressed genes under inflammatory conditions and restoration of basic network following CS treatment. Although results of the present study imply a possible engagement of ADCYAP1 and BPIFA1 as biomarkers for CRSwNP, a more profound study taking into account disease severity and CRSwNP endotypes prior to the treatment would provide additional information on their sensitivity.

Identification of lncRNA Biomarkers and LINC01198 Promotes Progression of Chronic Rhinosinusitis with Nasal Polyps through Sponge miR-6776-5p

Background

Chronic sinusitis (CRS) was a chronic inflammation that originated in the nasal mucosa and affected the health of most people around the world. Chronic rhinosinusitis with nasal polyps (CRSwNP) was one kind of chronic sinusitis. Emerging research had suggested that long noncoding RNAs (lncRNAs) played vital parts in inflammatories and inflammation development.

Methods

We acquired GEO data to analyze the differential expression between the miRNA, immune genes, TF, and lncRNA data in CRSWNP and the corresponding control tissues. Bioinformatic analysis by coexpression of endogenous RNA network and competitive way enrichment, analysis, and forecasting functions of these noncoding RNA. The different pathway expressions in CRSwNP patients were confirmed using GSVA to analyze the differentially expressed immune genes and TF data sets in CRSwNP patients. The differential immune gene and transcription factor data set in CRSwNP perform functional notes and protein-protein interaction (PPI) network structure. We predicted the potential genes and RNAs related to CRSWNP by constructing a ceRNA network. In addition, we also used 19 hub immune genes to predict the potential drugs of CRSWNP. lncRNA biomarkers in CRSwNP were identified by lncRNAs LASSO regression. The CIBERSORT algorithm was used to contrast the divergence in immune infiltrations between CRSwNP and usual inferior turbinate organizations in 22 immunocyte subgroups.

Results

We identified a total of 48 miRNAs, 304 lncRNAs, 92 TFs, and 525 immune genes as CRSwNP-specific RNAs. GO and KEGG pathways both analyzed differentially expressed immune genes and transcription factor data sets. We predicted the potential genes GNG7, TUSC8, LINC01198, and has-miR-6776-5p by constructing ceRNA and PPI networks. At the same time, we found that the above genes were involved in two important pathways: chemokine signal path and PI3K/AKT signal path. In addition, we predicted 5 small molecule drugs to treat CRSwNP by analyzing 19 central immune genes, namely, danazol, ikarugamycin, semustine, cefamandole, and molindone. Finally, we identified 5 biomarkers in CRSwNP, namely, LINC01198, LINC01094, LINC01798, LINC01829, and LINC01320.

Conclusions

We had identified CRSwNP-related miRNAs, lncRNAs, TFs, and immune genes, which may be making use of latent therapeutic target for CRSwNP. At the same time, we identified 5 lncRNA biomarkers in CRSwNP. The results of this study showed that LINC01198 promoted the progression of CRSwNPs through spongy miR-6776-5p. Our studies provide a new way for further analyses of the pathogenesis of CRSwNP.

Analysis of competing endogenous RNA (ceRNA) crosstalk in eosinophilic chronic rhinosinusitis with nasal polyps

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNP) is one of the most common chronic inflammatory diseases, and has various phenotypes. Although its pathophysiology remains obscure, evidence has shown that dysregulation of noncoding RNAs (ncRNAs) is associated with CRSwNP. ncRNAs in the cytoplasm can act as competing endogenous RNAs (ceRNAs), which are involved in many inflammatory processes. However, the ceRNA crosstalk in CRSwNP is still unclear METHODS: We investigated expression profiles of messenger RNA (mRNA), microRNAs (miRNAs), and long noncoding RNAs (lncRNAs) in eosinophilic CRSwNP and constructed a global triple ceRNA network.

RESULTS

As a result, 964 differentially expressed mRNAs (DEmRs), 207 differentially expressed miRNAs (DEmiRs), and 15 differentially expressed lncRNAs (DElncRs) were identified, and a ceRNA network containing 598 miRNA-mRNA pairs and 70 lncRNA-miRNA pairs was finally constructed. Gene set enrichment analysis (GSEA) results indicated these DEmRs were mainly enriched in "cytokine-cytokine receptor interaction," "salivary secretion," "hematopoietic cell lineage," and "chemokine signaling pathway." Moreover, we also predicted the subcellular localization of the DElncRs identified in the network via bioinformatics approaches  CONCLUSION: In summary, the present study provided the first comprehensive assessment of the ceRNA crosstalk in eosinophilic CRSwNP. These findings will be of interest to the understanding of the potential pathophysiology of this disease.

Results of Frequency Analysis Distribution of Polymorphism Rs1800895 592C>A In IL10 Gene among Patients with Chronic Polypoid Rhinosinusitis

INTRODUCTION

Chronic polyposis rhinosinusitis is a disease characterized by chronic inflammation of the nasal mucosa and sinuses. In the tissues of polyps and intranasal secretions, an increase in the concentration of various inflammatory mediators, in particular interleukins is observed due to an increase in their de novo synthesis by effector cells. The research objective to study the distribution of genotypic forms of the IL10 gene locus and evaluate their role in the development and clinical course of chronic polypoid rhinosinusitis.

MATERIAL AND METHODS

In accordance with the purpose of the study and to fulfill the assigned tasks, clinical studies were carried out in 140 patients with CPRS and with chronic rhinosinusitis, who were examined and treated at the ENT department of the multidisciplinary clinic of the Tashkent Medical Academy in 2017-2019. The examined patients met the following criteria: the presence of polyposis tissue in the nasal cavity that obstructs the common nasal passage completely or by at least 50%; complaints of prolonged difficulty in nasal breathing; according to the patient, the disease significantly reduces the quality of his life; absence of acute inflammatory pathology; written informed consent for surgical treatment and morphological examination of the surgical material.

RESULTS AND DISCUSSION

The revealed reliably high frequency of this genotype in group 1 of patients with CPRS, compared with group 2 of CPRS, also confirms our assumption about the protective role of the genotypic variant of the A/A polymorphism rs1800895 592 C>A in the IL10 gene, in relation to the development of CPRS in patients (6.45 % versus 5.0%, respectively, at χ2=0.02; Р=0.45; RR=1.17; OR=1.18; 95% CI: 8.557-8.942). This fact is probably due to the fact that in carriers of the A/A genotype of the IL10 gene, the anti-inflammatory activity of epithelial matrix metalloproteinases is significantly increased, compared with patients carrying other genotypic variants.

CONCLUSION

The results obtained showed that, with this pathology of the genotypic variant of the A/A polymorphism rs1800895 592 C>A in the IL10 gene, there is a risk of developing CPRS in patients (6.45% versus 5.0%, respectively). This fact is probably due to the fact that in carriers of the A/A genotype of the IL10 gene, the anti-inflammatory activity of epithelial matrix metalloproteinases is significantly increased, compared with patients carrying other genotypic variants.

DEP-induced ZEB2 promotes nasal polyp formation via epithelial-to-mesenchymal transition

BACKGROUND

Diesel exhaust particles (DEPs) are associated with the prevalence and exacerbation of allergic respiratory diseases, including allergic rhinitis and allergic asthma. However, DEP-induced mechanistic pathways promoting upper airway disease and their clinical implications remain unclear.

OBJECTIVE

We sought to investigate the mechanisms by which DEP exposure contributes to nasal polyposis using human-derived epithelial cells and a murine nasal polyp (NP) model.

METHODS

Gene set enrichment and weighted gene coexpression network analyses were performed. Cytotoxicity, epithelial-to-mesenchymal transition (EMT) markers, and nasal polyposis were assessed. Effects of DEP exposure on EMT were determined using epithelial cells from normal people or patients with chronic rhinosinusitis with or without NPs. BALB/c mice were exposed to DEP through either a nose-only exposure system or nasal instillation, with or without house dust mite, followed by zinc finger E-box-binding homeobox (ZEB)2 small hairpin RNA delivery.

RESULTS

Bioinformatics analyses revealed that DEP exposure triggered EMT features in airway epithelial cells. Similarly, DEP-exposed human nasal epithelial cells exhibited EMT characteristics, which were dependent on ZEB2 expression. Human nasal epithelial cells derived from patients with chronic rhinosinusitis presented more prominent EMT features after DEP treatment, when compared with those from control subjects and patients with NPs. Coexposure to DEP and house dust mite synergistically increased the number of NPs, epithelial disruptions, and ZEB2 expression. Most importantly, ZEB2 inhibition prevented DEP-induced EMT, thereby alleviating NP formation in mice.

CONCLUSIONS

Our data show that DEP facilitated NP formation, possibly via the promotion of ZEB2-induced EMT. ZEB2 may be a therapeutic target for DEP-induced epithelial damage and related airway diseases, including NPs.

Let-7a-5p regulates the inflammatory response in chronic rhinosinusitis with nasal polyps

BACKGROUND

Let-7a-5p is demonstrated to be a tumor inhibitor in nasopharyngeal carcinoma. However, the role of let-7a-5p in chronic rhinosinusitis with nasal polyps (CRSwNP) has not been reported. This study is designed to determine the pattern of expression and role of let-7a-5p in CRSwNP.

METHODS

The expression level of let-7a-5p, TNF-α, IL-1β, and IL-6 in CRSwNP tissues and cells were detected by RT-qPCR. Western blot assay was carried out to measure the protein expression of the Ras-MAPK pathway. Dual luciferase reporter assay and RNA pull-down assay were used to explore the relationship between let-7a-5p and IL-6.

RESULTS

Let-7a-5p was significantly downregulated in CRSwNP tissues and cells. Moreover, the mRNA expression of TNF-α, IL-1β and IL-6 was increased in CRSwNP tissues, while let-7a-5p mimic inhibited the expression of TNF-α, IL-1β and IL-6. Besides that, let-7a-5p was negatively correlated with TNF-α, IL-1β and IL-6 in CRSwNP tissues. In our study, IL-6 was found to be a target gene of let-7a-5p. Additionally, let-7-5p mimic obviously reduced the protein levels of Ras, p-Raf1, p-MEK1 and p-ERK1/2, while IL-6 overexpression destroyed the inhibitory effect of let-7a-5p on the Ras-MAPK pathway in CRSwNP.

CONCLUSION

We demonstrated that let-7a-5p/IL-6 interaction regulated the inflammatory response through the Ras-MAPK pathway in CRSwNP.

Interleukin 13 (IL-13) alters hypoxia-associated genes and upregulates CD73

BACKGROUND

Interleukin 13 (IL-13) is a pleiotropic cytokine that has been shown to be important in the pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP) and other type 2 inflammation-related diseases. Increased IL-13 expression can elicit several pro-inflammatory effects, including eosinophilia, and pathology such as increased mucus secretion. Polypogenesis in chronic rhinosinusitis (CRS) can be caused by hypoxia, which can also lead to hyperpermeability of airway epithelium and epithelium-to-mesenchymal translation through the upregulation of hypoxia-associated genes, such as HIF1. Whether T-helper 2 (Th2) inflammatory cytokines, such as IL-13, can also induce sinonasal epithelial hypoxia-associated genes is currently unknown.

METHODS

Human air-liquid interface (ALI) sinonasal epithelial cell cultures treated with recombinant IL-13 were analyzed by real-time polymerase chain reaction (PCR) and flow cytometry to determine the effect on epithelial cells.

RESULTS

Whole tissue from CRSwNP subjects showed increased HIF1A gene expression. Treatment of fully differentiated human ALI cultures with IL-13 resulted in a concurrent increase in HIF1A and ARNT messenger RNA (mRNA) expression. However, the level of EPAS1 expression was significantly reduced. IL-13 also had a dose-dependent response on the expression of HIF genes and the time course experiment showed peak expression of HIF1A and ARNT at 5 to 7 days poststimulation. Remarkably, CD73 surface expression also peaked at day 5 poststimulation.

CONCLUSION

Our data suggests that IL-13 can induce hypoxia signaling pathway genes leading to surface expression of CD73, which has an anti-inflammatory effect.

Differential Expression of TFF1 and TFF3 in Patients Suffering from Chronic Rhinosinusitis with Nasal Polyposis

Trefoil family factor (TFF) proteins contribute to antimicrobial defense and the maintenance of sinonasal epithelial barrier integrity. Dysregulation of TFF expression may be involved in the development of chronic inflammation and tissue remodeling characteristically found in chronic rhinosinusitis with nasal polyposis (CRSwNP). Expressions of TFF1 and TFF3 were determined in specimens of middle nasal turbinate (MNT-0), bulla ethmoidalis (BE), and nasal polyps (NP) from CRSwNP patients (n = 29) and inferior nasal turbinate from a group of control patients (underwent nasal septoplasty, n = 25). An additional MNT sample was collected 6 months after functional endoscopic sinus surgery (FESS, MNT-6). TFF1 mRNA levels were significantly reduced in all specimens by approximately three- to five-fold, while TFF3 was increased in MNT-0, as compared with controls. Six months after surgery their levels were reversed to control values. CRSwNP patients with S. epidermidis isolated from sinus swabs showed upregulation of TFF3 in MNT and NP as compared with patients with sterile swabs. Target gene regulation was not affected by the presence of type 2 inflammation in patients with confirmed allergy. Results of this study imply participation of TFFs genes in the development of CRSwNP.

TGF-β1-induced HSP47 regulates extracellular matrix accumulation via Smad2/3 signaling pathways in nasal fibroblasts

HSP47 is required for the production of collagen and serves an important role in tissue remodeling, a pathophysiologic mechanism of chronic rhinosinusitis (CRS). We investigated the relationship between HSP47 expression and tissue remodeling in CRS. We also determined the underlying molecular mechanisms of TGF-β1-induced HSP47 and extracellular matrix (ECM) production in nasal fibroblasts. HSP47, α-SMA, fibronectin, and collagen type I expression levels were measured using real-time PCR, western blotting, and immunofluorescence staining. Fibroblast migration was analyzed using scratch and transwell migration assays. Contractile activity was measured with a collagen gel contraction assay. HSP47 is increased in patients with CRS without nasal polyps. TGF-β1 induced HSP47 expression in nasal fibroblasts. Myofibroblast differentiation and ECM production, which are induced by TGF-β1, were inhibited by siHSP47. We also confirmed that the Smad2/3 signaling pathway is involved in TGF-β1-induced HSP47 expression in nasal fibroblasts. In a functional assay, TGF-β1-enhanced migration and contraction ability were inhibited by HSP47 knockout. Glucocorticoid reversed the stimulatory effects of TGF-β1 on HSP47 expression and ECM production in nasal fibroblasts and ex vivo organ cultures. HSP47 expression is involved in TGF-β1-induced myofibroblast differentiation and ECM production through the Smad2/3 signaling pathway, which might contribute to tissue remodeling in chronic rhinosinusitis.

Correlation Between HMGB1 and TLR4 Expression in Sinonasal Mucosa in Patients With Chronic Rhinosinusitis

OBJECTIVES

Chronic rhinosinusitis (CRS) is one of the most common inflammations in the upper airway. Despite the wide prevalence of CRS, the pathogenesis of this disease is poorly understood. Several components of the innate immune system may play a significant role in CRS, including Toll-like receptor 4 (TLR4), TLR9, and high-mobility group box 1 protein (HMGB1). This study was conducted to determine the expression of TLR4, TLR9, HMGB1, and pNFκ-B p65 in paraffin-embedded blocks of patients with CRS with nasal polyps compared with those of the control group.

METHODS

Twenty-six formalin-fixed, paraffin-embedded samples from patients with confirmed CRS and 26 patients undergoing septoplasty due to anatomic variations and no other inflammatory nasal diseases as the control group were assessed. Expression patterns of HMGB1, TLR9, TLR4, and pNFκ-B p65 genes were examined using real-time quantitative reverse transcription polymerase chain reaction (Real-Time qRT-PCR). Statistical analyses were performed with SPSS and analyzed using unpaired 2-tailed t tests or 1-way analysis of variance.

RESULTS

Real-time PCR showed that the expression level of HMGB1 messenger RNA was significantly increased in the tissues of patients with CRS compared with controls (P < .05). The other 3 genes were also upregulated in the patients, but were not significant compared with control. Analysis of the Pearson correlation coefficient (r) revealed a significant positive correlation between HMGB1 and TLR4 (r = 0.79, P < .05) in patients and negative correlation between TLR4 and NfκB in the control group (r = 0.94; P < .05).

CONCLUSIONS

Both HMGB1 and TLR4 are increased in the paranasal sinus mucosa of patients with CRS. These results suggest a possible contribution of HMGB1 and its internal receptor (TLR4) in the pathophysiology of CRS.

Evaluation of the frequency of invariant natural killer T (iNKT) cells in nasal polyps

Nasal polyps (NP) are associated with inflamed mucosa of unknown etiology. The role of T cells in nasal polyposis is unclear. Invariant natural killer T cells (iNKT) can promote Th2 responses and have been implicated in some types of asthma. As there are shared inflammatory pathways involved in asthma and NPs, we evaluated the frequency of iNKT in 17 patients with NPs, but without asthma. A median of 6% polyp cells were T lymphocytes, of which iNKT were 0 to 2.38% (mean 0.674%). In the matched group (n = 10), iNKT in NPs was significantly higher than PBMCs (1.057% vs 0.155%, P < 0.05). Relative expression of Vα24 to TCR-beta genes in polyps (n = 14) was higher than blood in matched samples (n = 4). The presence of greater proportions of iNKT in NPs than in blood suggests that iNKT may play a role in the pathogenesis of nasal polyposis.

Upregulation of FZD5 in Eosinophilic Chronic Rhinosinusitis with Nasal Polyps by Epigenetic Modification

Eosinophilic chronic rhinosinusitis with nasal polyps (CRSwNP) is one of the most challenging problems in clinical rhinology. FZD5 is a receptor for Wnt5A, and its complex with Wnt5A contributes to activating inflammation and tissue modification. Nasal polyps and eosinophil/non-eosinophil counts are reported to be directly correlated. This study investigated the expression and distribution of FZD5, and the role of eosinophil infiltration and FZD5 in eosinophilic CRSwNP pathogenesis. The prognostic role of eosinophil levels was evaluated in seven patients with CRSwNP. Fifteen patients with CRS were classified based on the percentage of eosinophils in nasal polyp tissue. Methylated genes were detected using methyl-CpG-binding domain sequencing, and qRT-PCR and immunohistochemistry were used to detect FZD5 expression in nasal polyp tissue samples. The results showed that mRNA expression of FZD5 was upregulated in nasal polyps. FZD5 expression was significantly higher in nasal polyp samples from patients with eosinophilic CRSwNP than in those from patients with non-eosinophilic CRSwNP, as indicated by immunohistochemistry. Furthermore, inflammatory cytokine levels were higher in eosinophilic CRSwNP-derived epithelial cells than in normal tissues. In conclusion, FZD5 expression in nasal mucosal epithelial cells is correlated with inflammatory cells and might play a role in the pathogenesis of eosinophilic CRSwNP.

Identification of key genes and pathways in chronic rhinosinusitis with nasal polyps using bioinformatics analysis

PURPOSE

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a prevalent inflammatory disease of yet unknown etiology. The purpose of this study was to uncover key genes and pathways related to the pathogenesis of CRSwNP via bioinformatics approaches.

MATERIALS AND METHODS

The gene expression profile of GSE36830 extracted from Gene Expression Omnibus database was used to screen differentially expressed genes (DEGs) between nasal polyp samples and control samples. Furthermore, functional and pathway enrichment analysis was performed using the clusterProfiler package in R language. In addition, protein-protein interaction (PPI) network was constructed by STRING database and functional modules were detected using Molecular Complex Detection algorithm.

RESULTS

A total of 538 DEGs (326 up-regulated and 212 down-regulated) were identified. The most significantly enriched pathways for up-regulated and down-regulated genes were hematopoietic cell lineage and salivary secretion, respectively. Moreover, twenty hub genes with high connectivity degrees were selected from the PPI network, such as TYRO protein tyrosine kinase binding protein (TYROBP), G protein subunit gamma 2 (GNG2), CCR7, and CCR3. Besides, six important modules were obtained, which were highly associated with chemokine signaling pathway, Th1 and Th2 cell differentiation, complement and coagulation cascades, cell cycle, systemic lupus erythematosus, and Staphylococcus aureus infection.

CONCLUSIONS

The results of this study may provide new insights into potential molecular mechanisms of CRSwNP. Nevertheless, further experiments are needed to confirm these findings.

Role of the TAp63 Isoform in Recurrent Nasal Polyps

The pathogenic molecular mechanisms underlying the insurgence of nasal polyps has not been completely defined. In some patients, these lesions can have a recurrence after surgery removal, and the difference between recurrent and not recurrent patients is still unclear. To molecularly characterize and distinguish between these two classes, a cohort of patients affected by nasal polyposis was analysed. In all patients we analysed the p63 isoform expression using fresh tissues taken after surgery. Moreover, confocal immunofluorescence analysis of fixed sections was performed. The results show high ΔNp63 expression in samples from the nasal polyps of patients compared to the normal epithelia. Analysis of the expression level of the TAp63 isoform shows differential expression between the patients with recurrence compared to those not recurring. The data, considered as the ΔN/TAp63 ratio, really discriminate the two groups. In fact, even though ΔNp63 is expressed in non-recurrent patients, the resulting ratio ΔN/TAp63 is significantly lower in these patients. This clearly indicates that the status of TAp63 expression, represented by the ΔN/TAp63 ratio, could be considered a prognostic marker of low recurrence probability. In these samples we also investigated the expression of OTX2 transcription factor, known to be a selective activator of TAp63, detecting a significant correlation. Database analysis of HNSCC patients showed increased survival for the patients presenting OTX2 amplification and/or overexpression. These results, together with the fact that TAp63 can be selectively upregulated by HDAC inhibitors, open the possibility to consider local treatment of recurrent nasal polyps with these molecules.

Interleukin-4 C-590T Polymorphism is associated with Protection against Nasal Polyps in a Korean Population

Background

Although many studies have implicated interleukin (IL)-4 promoter polymorphisms as potential determinants of disease susceptibility, there are no reports on the association between IL-4 promoter polymorphisms and nasal polyps. The aim of this study was to investigate the relationship between an IL-4 promoter polymorphism and nasal polyps.

Methods

The C-590T promoter polymorphism of the IL-4 gene was genotyped by polymerase chain reaction-restriction fragment length polymorphism analysis in 106 Korean chronic rhinosinusitis patients with or without nasal polyps and 70 healthy Korean subjects.

Results

The frequency of the T allele at position -590 of the IL-4 gene in a Korean population was 0.85, which was significantly higher than those of other ethnic groups, and the T/T allele at position -590 of IL-4 was associated with protection against nasal polyps if compared with the C/C allele (relative risk, 0.529; 95% confidence interval, 0.307–0.912; p = 0.028).

Conclusion

T-590, which is dominant at position -590 of the IL-4 promoter, appears to be associated with a protective mechanism against nasal polyps in Korean populations.

Functional role of kynurenine and aryl hydrocarbon receptor axis in chronic rhinosinusitis with nasal polyps

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNP) is associated with mast cell-mediated inflammation and heightened oxidant stress. Kynurenine (KYN), an endogenous tryptophan metabolite, can promote allergen-induced mast cell activation through the aryl hydrocarbon receptor (AhR).

OBJECTIVES

We sought to determine the role of the KYN/AhR axis and oxidant stress in mast cell activation and the development of CRSwNP.

METHODS

We measured the expression of indoleamine 2,3-dioxygenase 1, tryptophan 2,3-dioxygenase, KYN, and oxidized calmodulin-dependent protein kinase II (ox-CaMKII) in nasal polyps and controls. KYN-potentiated ovalbumin (OVA)-induced ROS generation, cell activation, and ox-CaMKII expression were investigated in wild-type and AhR-deficient (AhR-/-) mast cells. The role of ox-CaMKII in mast cell activation was further investigated.

RESULTS

Nasal polyps in CRSwNP showed an increased expression of indoleamine 2,3-dioxygenase 1, tryptophan2,3-dioxygenase, and KYN compared with controls. AhR was predominantly expressed in mast cells in nasal polyps. Activated mast cells and local IgE levels were substantially increased in eosinophilic polyps compared with noneosinophilic polyps and controls. Furthermore, KYN potentiated OVA-induced ROS generation, intracellular Ca2+ levels, cell activation, and expression of ox-CaMKII in wild-type, but not in AhR-/- mast cells. Compared with noneosinophilic polyps and controls, eosinophilic polyps showed increased expression of ox-CaMKII in mast cells. Mast cells from ROS-resistant CaMKII MMVVδ mice or pretreated with CaMKII inhibitor showed protection against KYN-promoted OVA-induced mast cell activation.

CONCLUSIONS

These studies support a potentially critical but previously unidentified function of the KYN/AhR axis in regulating IgE-mediated mast cell activation through ROS and ox-CaMKII in CRSwNP.

[The influence of the vitamin D3 level in the blood serum of lactase gene polymorphism on the development of chronic polypous rhinosinusitis]

The objective of the present study was to elucidate the possible correlations between the vitamin D₃ level in the blood serum and lactase gene polymorphism (LCT-13910 T>C) in the patients presenting with chronic polypous rhinosinusitis (CPRS). The study included 50 patients with this condition and 14 subjects comprising the control group. The variants of lactase gene polymorphism (LCT-13910 T>C) were identified with the use of polymerase chain reaction (PCR) in real time. The total level of serum vitamin D₃ (VD₃) was determined by means of the immunochemical analysis (the electrochemiluminescence technique). In the group of patients presenting with chronic polypous rhinosinusitis, the level of VD₃ in the blood serum ranged from 48 nm/l to 85 nm/l (mean 60 nm/l) compared with that in the patients of the control group (from 78 nm/l to 112 nm/l; mean 97 nm/l) . The level of vitamin D₃ 'below the normal values' was documented in 71% of the patients with CPRS in comparison with 7% in the control subjects. Lactase gene polymorphism (LCT-13910 CC, CT) suggesting pronounced and latent hypolactasia was identified in 94% of the patients with CPRS compared with 78.6% in the control group. The occurrence of the CC genotype in the patients of both study groups was virtually identical: 52% in the patients presenting with chronic polypous rhinosinusitis and 57% in the control group. CT polymorphism was identified in 42% of the patients with CPRS and in 21% of the control subjects. The significant difference between the patients of the two groups was documented for the occurrence of TT polymorphism: 6% among the patients with CPRS and 21% in the controls (i.e. much higher in the healthy subjects). There was no significant difference between the serum levels of vitamin D₃ either among the patients with CPRS having LCT-13910 gene polymorphisms (CC, CT, TT) or among the control subjects. It is concluded that the study revealed the higher levels of vitamin D₃ in the blood sera from the control subjects in comparison with that in the patients with chronic polypous rhinosinusitis. Moreover, the patients of the latter group more frequently exhibited the variant of the LCT CT-13910 gene polymorphism suggesting latent hypolactasia whereas the subjects comprising the control group more frequently had the variant of the LCT CT-13910 gene polymorphism indicative of the normal tolerance of lactose.

A family-based genome-wide association study of chronic rhinosinusitis with nasal polyps implicates several genes in the disease pathogenesis

BACKGROUND

The pathogenesis of chronic rhinosinusitis with nasal polyps is largely unknown. Previous studies have given valuable information about genetic variants associated with this disease but much is still unexplained. Our goal was to identify genetic markers and genes associated with susceptibility to chronic rhinosinusitis with nasal polyps using a family-based genome-wide association study.

METHODS

427 patients (293 males and 134 females) with CRSwNP and 393 controls (175 males and 218 females) were recruited from several Swedish hospitals. SNP association values were generated using DFAM (implemented in PLINK) and Efficient Mixed Model Association eXpedited (EMMAX). Analyses of pathway enrichment, gene expression levels and expression quantitative trait loci were then performed in turn.

RESULTS

None of the analysed SNPs reached genome wide significant association of 5.0 x 10-8. Pathway analyses using our top 1000 markers with the most significant association p-values resulted in 138 target genes. A comparison between our target genes and gene expression data from the NCBI Gene Expression Omnibus database showed significant overlap for 36 of these genes. Comparisons with data from expression quantitative trait loci showed the most skewed allelic distributions in cases with chronic rhinosinusitis with nasal polyps compared with controls for the genes HLCS, HLA-DRA, BICD2, VSIR and SLC5A1.

CONCLUSION

Our study indicates that HLCS, HLA-DRA, BICD2, VSIR and SLC5A1 could be involved in the pathogenesis of chronic rhinosinusitis with nasal polyps. HLA-DRA has been associated with chronic rhinosinusitis with nasal polyps in previous studies and HLCS, BICD2, VSIR and SLC5A1 may be new targets for future research.

Anti-inhibitory potential of an ethanolic extract of Distromium decumbens on pro-inflammatory cytokine production in Pseudomonas aeruginosa lipopolysaccharide-stimulated nasal polyp-derived fibroblasts

Marine algae are rich sources of biologically active compounds that may present useful leads in the development of pharmaceuticals, nutraceuticals, and functional foods. The main aim of this study was to identify the possible anti-inflammatory effects of Distromium decumbens in nasal polyp-derived fibroblasts (NPDFs) and its associated mechanism of action. NPDFs were stimulated by Pseudomonas aeruginosa lipopolysaccharide (PA-LPS) and treated with an ethanolic extract of Distromium decumbens (DDE). The production of interleukin-6 (IL-6) and IL-8 in the supernatant, the phosphorylation of mitogen-activated protein kinase (MAPK) molecules [extracellular signal-related kinase 1/2 (ERK1/2), c-Jun N-terminal kinase and p38 MAPK] and Akt, and the activation of nuclear factor-κB (NF-κB) were assayed in the PA-LPS-stimulated NPDFs untreated or treated with DDE. The expression levels of IL-6 and IL-8 in PA-LPS-exposed NPDFs were detected using enzyme-linked immunosorbent assays. The mechanisms by which DDE regulates cellular signaling cascades were investigated using electrophoretic mobility shift assays and western blot analysis. Functional validation was performed by measuring the inhibitory effects of DDE on neutrophil migration in vitro. DDE reduced the expression of IL-6 and IL-8 stimulated by PA-LPS in NPDFs. The activation of ERK1/2, Akt and NF-κB by PA-LPS was inhibited by DDE. Inhibitors of ERK1/2, Akt and NF-κB inhibited the expression of IL-6 and IL-8. In addition, DDE significantly attenuated PA-LPS-induced migration of differentiated HL-60 cells. The present findings suggest that DDE potently inhibits inflammation through the ERK1/2, Akt and NF-κB signaling pathways in NPDFs.

The role of cysteinyl leukotrienes and their receptors in refractory nasal polyps

Leukotriene signaling is essential in many diseases, including asthma, allergic rhinitis, atherosclerosis and inflammatory bowel disease. Nevertheless, the expression of cysteinyl leukotrienes (CysLTs) and its receptors (CYSLTRs) in different types of nasal polyps (NPs), and the role of their antagonist in the treatment of refractory chronic rhinosinusitis with nasal polyps (CRSwNP) are not well understood. The following study investigates the expression of CysLTs and CYSLTRs in different types of NPs, as well as the role of leukotriene receptor antagonist (montelukast) in refractory NPs. Our data showed that CysLTs and CYSLTRs were significantly elevated in CRSwNP group (p < 0.05), particularly in IL-5⁺NP patients^, compared to patients with chronic rhinosinusitis but without NPs (CRSsNP) and the control group. Furthermore, montelukast have shown the ability to inhibit the expression of MUC5AC, TSLP, IL-4, IL-5, IL-13, and TGF-β in NP explants after treatment with Staphylococcal Enterotoxins B (SEB). In addition, the patients treated by additional montelukast have better outcomes compared to those with INCS only. To conclude, our results demonstrate that the inhibition of CysLTs signaling by montelukast decreases the expression of cytokines and mucin in polyp explants, and in turn promotes the recovery in patients with refractory CRSwNP.