S100a9 might act as a modulator of the Toll-like receptor 4 transduction pathway in chronic rhinosinusitis with nasal polyps

Chronic rhinosinusitis with nasal polyp (CRSwNP) is a highly prevalent disorder characterized by persistent nasal and sinus mucosa inflammation. Despite significant morbidity and decreased quality of life, there are limited effective treatment options for such a disease. Therefore, identifying causal genes and dysregulated pathways paves the way for novel therapeutic interventions. In the current study, a three-way interaction approach was used to detect dynamic co-expression interactions involved in CRSwNP. In this approach, the internal evolution of the co-expression relation between a pair of genes (X, Y) was captured under a change in the expression profile of a third gene (Z), named the switch gene. Subsequently, the biological relevancy of the statistically significant triplets was confirmed using both gene set enrichment analysis and gene regulatory network reconstruction. Finally, the importance of identified switch genes was confirmed using a random forest model. The results suggested four dysregulated pathways in CRSwNP, including "positive regulation of intracellular signal transduction", "arachidonic acid metabolic process", "spermatogenesis" and "negative regulation of cellular protein metabolic process". Additionally, the S100a9 as a switch gene together with the gene pair {Cd14, Tpd52l1} form a biologically relevant triplet. More specifically, we suggested that S100a9 might act as a potential upstream modulator in toll-like receptor 4 transduction pathway in the major CRSwNP pathologies.

TGF-β1 induces epithelial-to-mesenchymal transition in chronic rhinosinusitis with nasal polyps through microRNA-182

BACKGROUND

Epithelial-to-mesenchymal transition (EMT) in nasal epithelial cells is involved in tissue remodeling of chronic rhinosinusitis with nasal polyps (CRSwNP). Our study investigated the molecular mechanisms that microRNA-182 (miR-182) regulated EMT in eosinophilic (Eos) and non-eosinophilic (non-Eos) CRSwNP.

OBJECTIVE

To investigate the mechanism by which miR-182 regulates EMT in human nasal epithelial cells (hNEPCs).

METHODS

The expression of EMT markers (E-cadherin, N-cadherin and vimentin), transforming growth factor (TGF)-β1, and miR-182 were determined by western blotting and reverse transcription-quantitative PCR (RT-qPCR). Fluorescence in situ hybridization (FISH) was used to detect the miR-182 localization. Additionally, EMT markers expression and cell morphology changes were checked upon treatment with TGF-β1, or TGF-β1 with miR-182 inhibitor, or miR-182 mimics, or miR-182 inhibitor alone in hNEPCs.

RESULTS

In both Eos CRSwNP and non-Eos CRSwNP, the expression levels of E-cadherin were downregulated while the expression levels of N-cadherin, vimentin, TGF-β1 and miR-182 were significantly upregulated compared with control nasal tissues. Additionally, more significant changes in these EMT markers were observed in the Eos-CRSwNP when compared with the non-Eos CRSwNP. Invitro hNEPCs model, TGF-β1 upregulated miR-182 expression and promoted EMT in hNEPCs, indicated by changes in cell morphology and EMT markers expression. Furthermore, these upregulations were reversed by miR-182 inhibitor.

CONCLUSIONS

This study showed that miR-182-induced EMT in response to TGF-β1 might promote nasal polypogenesis in both Eos CRSwNP and non-Eos CRSwNP, thus providing potential targets for the future development of novel therapeutic approaches for the management of CRSwNP.

Identification of Pyroptosis-Related Genes Regulating the Progression of Chronic Rhinosinusitis with Nasal Polyps

INTRODUCTION

Chronic rhinosinusitis with nasal polyps (CRSwNP) is an immunologic disease, and pyroptosis, an inflammation-based cellular death, strictly modulates CRSwNP pathology, whereas the pyroptosis genes and mechanisms involved in CRSwNP remain unclear. Herein, we explored disease biomarkers and potential therapeutic targets for pyroptosis and immune regulation in CRSwNP using bioinformatics analysis and tissue-based verification.

METHODS

We retrieved the transcriptional profiles of the high-throughput dataset GSE136825 from the Gene Expression Omnibus database, as well as 170 pyroptosis-related gene expressions from GeneCards. Using R, we identified differentially expressed pyroptosis-related genes and examined the potential biological functions of the aforementioned genes using Gene Ontology, Kyoto Encyclopedia of the Genome pathway, immune infiltration, and protein-protein interaction (PPI) network analyses, thereby generating a list of hub genes. The hub genes were, in turn, verified using real-time quantitative polymerase chain reaction (qRT-PCR), immunohistochemistry (IHC), and Western blotting (WB). Ultimately, using the StarBase and miRTarBase databases, we estimated the targeting microRNAs and long chain non-coding RNAs.

RESULTS

We demonstrated that the identified pyroptosis-related genes primarily modulated bacterial defense activities, as well as inflammasome immune response and assembly. Moreover, they were intricately linked to neutrophil and macrophage infiltration. Furthermore, we validated the tissue contents of hub genes AIM2, NLPR6, and CASP5 and examined potential associations with clinical variables. We also developed a competitive endogenous RNA (ceRNA) modulatory axis to examine possible underlying molecular mechanisms.

CONCLUSION

We found AIM2, CASP5, and NLRP6, three hub genes for pyroptosis in chronic rhinosinusitis with nasal polyps, by biological analysis, experimental validation, and clinical variable validation.

The influence of inhibitors of apoptosis proteins (IAPs) on chronic rhinosinusitis with nasal polyps

BACKGROUND

Inhibitors of apoptosis proteins (IAPs) modulate the inflammatory process, and may facilitate the formation of chronic rhinosinusitis with nasal polyps (CRSwNP). This study aimed to observe if IAPs were differently expressed between patients with CRSwNP and controls, and to correlate the expression of IAPs with some inflammatory markers, as with the response to nasal corticosteroids in patients with CRSwNP.

METHODOLOGY

We obtained nasal biopsies from patients with CRSwNP (n=27) and controls (n=16). qRT-PCR measured the expression of IAPs and caspases, while Luminex assay measured the concentration of cytokines. Unpaired parametric tests and Principal Component Analysis (PCA) were used for statistical analysis.

RESULTS

We observed lower expression of IAP genes (XIAP, BIRC2/IAP1, and BIRC3/IAP2) in CRSwNP patients compared to controls, and we identified that patients with bad response to corticosteroids presented lower levels of BIRC2/IAP1, XIAP, BCL2, CASP9, and IL-17, and higher levels of CASP7 and TGF-B.

CONCLUSIONS

IAPs expression was downregulated in CRSwNP, and was associated with poorer response to nasal corticosteroids. The present findings suggest the importance of IAPs as a link between environment and the host inflammatory responses, and this pathway could be explored as a potential new target therapy for patients with CRSwNP.

The current findings in eosinophilic chronic rhinosinusitis

Chronic rhinosinusitis (CRS) is a persistent inflammatory disease of the nasal cavity and paranasal sinuses. Traditional classification is denoted by the presence (CRSwNP) or absence of nasal polyps (CRSsNP). Particularly, CRSwNP is distinguished by the presence of infiltrating cells and inflammatory markers in the nasal mucosa. Patients with CRSwNP in Western countries predominantly display a type 2 endotype, whereas those in Asian regions display a mixed type 2 endotype. Nevertheless, recent transcriptome analyses have revealed two types of nasal polyps - type 2 and non-type 2 polyps, suggesting that geographical differences in endotypes likely resulted from the different proportions of each endotype. Moreover, various endotypes of CRSsNP have been identified, making phenotype a crucial factor for predicting treatment efficacy. Type 2 endotypes, designated as eosinophilic CRS (ECRS) in Japan, are characterized by severe eosinophilic infiltration into the paranasal sinus tissue and are particularly refractory. In this review, we discuss the latest developments in ECRS. We also provide recent findings on the involvement of nasal epithelial cells in pathogenesis.

Single-cell RNA sequencing reveals the epithelial cell, fibroblast, and key gene alterations in chronic rhinosinusitis with nasal polyps

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a chronic inflammatory disease of the nasal mucosa, and epithelial-mesenchymal transition (EMT) is thought to be an essential process in the pathogenesis of CRSwNP. However, the mechanisms of epithelial and fibroblastic changes at the single-cell level are unclear. In this study, we investigated the epithelial cell, fibroblast, and key gene alterations in the development of CRSwNP. We revealed major cell types involved in CRSwNP and nasal mucosal inflammation formation, then mapped epithelial and fibroblast subpopulations. We showed that the apical and glandular epithelial cells and the ADGRB3+ and POSTN+ fibroblasts were the key cell subtypes in the progression of CRSwNP. Pseudotime and cell cycle analysis identified dynamic changes between epithelial cells and fibroblasts during its development. WFDC2 and CCL26 were identified as the key marker genes involved in the development of CRSwNP and were validated by IHC staining, which may provide a potential novel target for future CRSwNP therapy. ScRNA-seq data provided insights into the cellular landscape and the relationship between epithelial cells and fibroblasts in the progression of CRSwNP. WFDC2 and CCL26 were identified as the key genes involved in the development of CRSwNP and may be the potential markers for gene therapy.

miR-200a-3p regulates epithelial-mesenchymal transition and inflammation in chronic rhinosinusitis with nasal polyps by targeting ZEB1 via ERK/p38 pathway

BACKGROUND

Several biological processes are regulated by miR-200a-3p, including cell proliferation, migration, and epithelial-mesenchymal transition (EMT). In this study we aimed to uncover the diagnostic value and molecular mechanisms of miR-200a-3p in chronic rhinosinusitis with nasal polyps (CRSwNP).

METHODS

The expressions of miR-200a-3p were detected by quantitative real-time polymerase chain reaction (qRT-PCR), Zinc finger E-box binding homeobox 1 (ZEB1) levels were examined by qRT-PCR and immunofluorescence staining. The interaction between miR-200a-3p and ZEB1 was predicted by TargetScan Human 8.0 and confirmed by dual-luciferase reporter assays. In addition, the effect of miR-200a-3p and ZEB1 on EMT-related makers and inflammation cytokines was assessed by qRT-PCR and Western blotting in human nasal epithelial cells (hNEpCs) and primary human nasal mucosal epithelial cells (hNECs).

RESULTS

We found that miR-200a-3p was downregulated in non-eosinophilic and eosinophilic CRSwNP patients when compared with controls. The diagnostic value of miR-200a-3p in serum is reflected by the receiver operating characteristic curve and the 22-item Sino-Nasal Outcome Test. Bioinformatic analysis and luciferase reporter assay identified ZEB1 as a target of miR-200a-3p. ZEB1 was more highly expressed in CRSwNP than in controls. Furthermore, miR-200a-3p inhibitor or ZEB1 overexpression significantly suppressed the epithelial marker E-cadherin; promoted the activation of vimentin, α-spinal muscle atrophy, and N-cadherin; and aggravated inflammation in hNEpCs. Knockdown of ZEB1 significantly alleviated the cellular remodeling caused by miR-200a-3p inhibitor via the extracellular signal-regulated kinase (ERK)/p38 pathway in hNECs.

CONCLUSIONS

miR-200a-3p suppresses EMT and inflammation by regulating the expression of ZEB1 via the ERK/p38 pathway. Our study presents new ideas for protecting nasal epithelial cells from tissue remodeling and finding a possible target for disease.

The inflammatory microenvironment of nasal polyps in patients with chronic rhinosinusitis and the relationship of this microenvironment with the nasal microbiome

BACKGROUND

We investigated the characteristics of the microbial community of the nasal sinuses in patients with chronic rhinosinusitis with nasal polyps (CRSwNP) and identified the correlations of the nasal microbiome with the inflammatory microenvironment of the nasal cavity.

METHODOLOGY

We collected matched nasal secretion and polyp tissue samples from 77 CRSwNP patients. Then, we extracted microbial DNA from cotton swabs, used high-throughput sequencing technology based on 16S ribosomal RNA (rRNA) to detect the bacterial community composition, and detected cytokines such as interleukin (IL)-5, IL-8, IL-17a, IL-17e, IL-18, IL-27 and interferon (INF)-gamma in the polyp tissue samples using Luminex. Eosinophils and neutrophils in the peripheral blood and polyp tissue were counted, and the relationships between inflammatory factors or inflammatory cell counts and nasal microbial diversity were analyzed.

RESULTS

Among the inflammatory factors evaluated, IL-5 had a positive rate of 32.47%, IFN-γ had a positive rate of 84.42%, IL-17A and IL-17E had positive rates of 75.32%, IL-18 had a positive rate of 94.81%, IL-27 had a positive rate of 68.83%, and IL-8 had a positive rate of 100%. IL-17a and IL-27 were negatively correlated with both Enterobacter and Anaerococcus, IL-8 was negatively correlated with both Enterobacter and Staphylococcus, IL-18 was positively correlated with Candidatus Arthromitus and negatively correlated with Haemophilus, and IL-27 was positively correlated with Faecalibaculum. Lactobacillus and Enterococcus were positively correlated with the degree of neutrophil infiltration in nasal polyp tissue.

CONCLUSIONS

In Southwest China, inflammation of the nasal polyps exhibits a variety of patterns. Enterobacteria and anaerobic bacteria may be correlated with the inflammatory pattern of nasal polyps. The neutrophil-mediated inflammatory response plays an important role in patients with CRSwNP in Southwest China.

Integrative analysis of immune-related signature profiles in eosinophilic chronic rhinosinusitis with nasal polyposis

Eosinophilic chronic rhinosinusitis with nasal polyps (ECRSwNP) is a subtype of chronic rhinosinusitis (CRS) that is associated with the nasal cavity and sinus polyps, elevated levels of eosinophils, and dysregulated immune responses to environmental triggers. The underlying cause of ECRSwNP is not well understood, and few studies have focused on the unique features of this subtype of CRS. Our study integrated proteomic and transcriptomic data with multi-omic bioinformatics analyses. We collected nasal polyps from three ECRSwNP patients and three control patients and identified 360 differentially expressed (DE) proteins, including 119 upregulated and 241 downregulated proteins. Functional analyses revealed several significant associations with ECRSwNP, including focal adhesion, hypertrophic cardiomyopathy, and extracellular matrix (ECM)-receptor interactions. Additionally, a protein-protein interaction (PPI) network revealed seven hub proteins that may play crucial roles in the development of ECRSwNP. We also compared the proteomic data with publicly available transcriptomic data and identified a total of 1077 DE genes. Pathways enriched by the DE genes involved angiogenesis, positive regulation of cell motility, and immune responses. Furthermore, we investigated immune cell infiltration and identified biomarkers associated with eosinophil and M2 macrophage infiltration using CIBERSORT and Weighted Gene Correlation Network Analysis (WGCNA). Our results provide a more complete picture of the immune-related mechanisms underlying ECRSwNP, which could contribute to the development of more precise treatment strategies for this condition.

Expression profiles of MMP-9 and EMMPRIN in chronic rhinosinusitis with nasal polyps

Objective

Metalloproteinases (MMPs) are implicated in tissue remodeling in chronic rhinosinusitis with nasal polyps (CRSwNP). This study aimed to evaluate the expression profiles of MMP-9 and the extracellular matrix metalloproteinase inducer (EMMPRIN) in nasal polyps compared to healthy mucosa.

Methods

Tissue samples from 37 CRSwNP patients undergoing functional endoscopic sinus surgery and mucosal specimens from 12 healthy controls were obtained intra-operatively. MMP-9 and EMMPRIN mRNA levels were assessed by reverse transcription-polymerase chain reaction and their protein expression by Western blot analysis.

Results

MMP-9 mRNA expression levels were significantly elevated in CRSwNP compared to controls (p < 0.05). MMP-9 protein levels presented an increasing trend but with no statistical significance (p > 0.05). No statistically significant difference in EMMPRIN mRNA and protein levels was identified.

Conclusions

Upregulation of MMP-9 in nasal polyps is evident and highlights its role in the pathogenesis of CRSwNP. The lack of concordance between MMP-9 mRNA and protein levels may be attributed to post-translational gene expression regulation. Although EMMPRIN expression was not significantly different between the two groups, its role remains to be elucidated. MMP-9 may be a valuable biomarker and treatment target in CRSwNP.

Utilization of Transcriptomic Profiling to Identify Molecular Markers Predicting Successful Recovery Following Endoscopic Sinus Surgery for Chronic Rhinosinusitis

OBJECTIVES

Successful recovery from chronic rhinosinusitis (CRS) following endoscopic sinus surgery (ESS) can be characterized by minimal presence of symptoms and absence of disease on endoscopy. However, molecular markers of surgical success remain to be characterized. These could allow for better tailoring of perioperative therapy. This study aims to identify novel molecular markers associated with surgery responsive patient.

STUDY DESIGN

Prospective cohort study.

SETTING

Single academic hospital center.

METHOD

One hundred eighteen consecutive patients with CRS at high risk of recurrence after surgery were followed prospectively following ESS in an academic medical center. Symptomatic and endoscopic outcomes were assessed at 4 months, with success rigorously defined subjectively as minimal or no symptoms (no symptom greater than 1 on an ordinal scale of 0-3) and objectively by the absence of nasal polyposis on sinus cavity endoscopy and Lund-Kennedy endoscopic edema score no greater than 1. Samples were obtained at the time of surgery and at 4-month postoperatively. Changes associated with surgery were determined by gene expression profiling using Affymetrix's Clariom S Human HT arrays.

RESULTS

Successful ESS was characterized by a mild upregulation in Type 1 inflammation, upregulation of cell cycle progression, and epithelial barrier and proliferation-associated genes and pathways. ESS failure was associated to very high levels of Type 1 inflammation along with downregulation of epithelial barrier function and regeneration genes and pathways.

CONCLUSION

Successful recovery from ESS involves restoration of epithelial function and regulated activation of Type 1 inflammation. Excessively elevated Type 1 inflammation is associated with epithelial barrier dysfunction.

Comparing Protein and Gene Expression Signature between Nasal Polyps and Nasal Fluids in Chronic Rhinosinusitis

INTRODUCTION

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a serious inflammatory condition. Nasal fluids (NFs) present a noninvasive alternative to nasal biopsy for studying CRSwNP pathogenesis. We aimed to compare the protein and mRNA inflammation signature between nasal polyps (NPs) and NFs.

METHOD

The performance of polyvinyl alcohol (PVA) sponges and NFs absorbable device (NFAD) for collecting NFs from 20 patients with CRSwNP was compared using the Luminex assay. The other group consisted of four healthy controls and an additional 21 CRSwNP patients (including eosinophilic CRSwNP [ECRSwNP] and non-eosinophilic CRSwNP [NECRSwNP]) for protein quantification by Olink platform and gene expression evaluation by RNA-sequencing. Spearman's analysis was performed to detect correlations between protein expression levels in NFs and clinical assessment variables.

RESULTS

NFAD-collected NFs contained at least a 2-fold higher concentration of cytokines than that obtained using PVA sponge, and these cytokines levels are significantly associated with NPs (ρ > 0.45, p < 0.05). Differentially expressed proteins between NFs and NPs were significantly correlated in the ECRSwNP subgroup compared with controls (ρ = 0.41, p < 0.01). Levels of Th2/IL-13, MCP4, and CCL4, characteristic of eosinophilic infiltration, were increased in ECRSwNP patients. A significant correlation between gene and protein expression was observed (ρ = 0.34, p < 0.01). PDL2 levels in NFs were positively correlated with ECRSwNP postoperative recurrence, the nasal VAS, and SNOT-22 scores (ρ > 0.68, p < 0.05 for all).

CONCLUSION

Our study revealed similarities and discrepancies in inflammatory signatures between NPs and NFs in the same CRSwNP patient.

Exploring causal relationships between inflammatory cytokines and allergic rhinitis, chronic rhinosinusitis, and nasal polyps: a Mendelian randomization study

Objectives

Previous research has suggested connections between specific inflammatory cytokines and nasal conditions, including Allergic Rhinitis (AR), Chronic Rhinosinusitis (CRS), and Nasal Polyps (NP). However, a lack of robust research establishing the causal underpinnings of them. This Mendelian Randomization (MR) study aims to evaluate the causal relationships between 41 inflammatory cytokines and the incidence of AR, CRS and NP.

Methods

This study employed a two-sample MR design, harnessing genetic variations derived from publicly accessible genome-wide association studies (GWAS) datasets. AR data was sourced from a GWAS with 25,486 cases and 87,097 controls (identifier: ukb-b-7178). CRS data originated from a GWAS encompassing 1,179 cases and 360,015 controls (identifier: ukb-d-J32). NP data was extracted from a GWAS involving 1,637 cases and 335,562 controls (identifier: ukb-a-541). The data for 41 inflammatory cytokines were obtained from an independent GWAS encompassing 8,293 participants. Inverse variance weighted (IVW), MR Egger regression and Weighted median were used to evaluate the causalities of exposures and outcomes. A range of sensitivity analyses were implemented to assess the robustness of the results.

Results

The results revealed significant associations between elevated circulating levels of MIP-1α (odds ratio, OR: 1.01798, 95% confidence interval, CI: 1.00217-1.03404, p = 0.02570) and TNF-α (OR: 1.01478, 95% CI: 1.00225-1.02746, p = 0.02067) with an augmented risk of AR in the IVW approach. Heightened levels of circulating IL-2 exhibited a positive correlation with an increased susceptibility to NP in the IVW approach (OR: 1.00129, 95% CI: 1.00017-1.00242, p = 0.02434), whereas elevated levels of circulating PDGF-BB demonstrated a decreased risk of NP (OR: 0.99920, 95% CI: 0.99841-0.99999, p = 0.047610). The MR analysis between levels of 41 inflammatory cytokines and the incidence of CRS yielded no positive outcomes.

Conclusion

This investigation proposes a potential causal association between elevated levels of MIP-1α and TNF-α with an elevated risk of AR, as well as an increased risk of NP linked to elevated IL-2 levels. Furthermore, there appears to be a potential association between increased levels of circulating PDGF-BB and a reduced risk of NP.

[The correlation between FCER2 gene polymorphism and the efficacy of inhaled corticosteroids in patients with chronic rhinosinusitis]

Objective:To investigate the correlation between FCER2（2206A>G） gene polymorphism and the efficacy of inhaled corticosteroids（ICS） in patients with chronic rhinosinusitis（CRS）. Methods:A total of 208 CRS patients were routinely treated with functional endonasal sinus surgery and postoperative ICS. DNA extraction, PCR amplification and gene sequencing were performed to observe the FCER2（2206A>G） gene polymorphism and calculate the allele frequency. The visual analog scale（VAS） score, Lund-Kennedy score, and computed tomography（CT） Lund-Mackay score were determined 6 months after surgery among patients with different genotypes. Moreover, the polymorphism frequency was compared among different subgroups（chronic rhinosinusitis with nasal polyps versus chronic rhinosinusitis without nasal polyps, eosinophilic chronic rhinosinusitis versus non-eosinophilic chronic rhinosinusitis）. Results:There were FCER2（2206A>G） gene polymorphism in patients with CRS, and the phenotypes included 3 genotypes, AA, AG and GG, with distribution frequencies of 68（32.7%）, 116（55.8%） and 24（11.5%） cases, respectively. No significant differences were found in age, VAS score, nasal endoscopic Lund-Kennedy score and CT imaging Lund-Mackay score among patients with CRS of each genotype before surgery. In patients with the AA genotype, the changes in VAS score（5.74±1.10）, Lund Kennedy score（5.92 ± 1.14）, and CT imaging Lund-Mackay score（13.26±4.26） were significantly higher than in patients with the AG（4.37±0.86, 5.37±1.24, 10.82±3.77） and GG（4.26±0.80, 5.18±1.56, 10.10±3.53） genotype（P<0.05）. However, there were no marked difference between patients with the AG genotype and those with the GG genotype（P>0.05）. Compared with patients with non-eosinophilic sinusitis, Among them, the differences between the GG genotype and AG /AA genes were more significant in eosinophilic sinusitis compared to non-eosinophilic sinusitis（P<0.01）. Conclusion:The FCER2（2206A>G） gene in patients with CRS has genetic polymorphism and is associated with the recovery of CRS patients after surgery, individual corticosteroid sensitivity, and subgroup variability.

Tissue Eosinophilia is Superior to an Analysis by Polyp Status for the Chronic Rhinosinusitis Transcriptome: An RNA Study

OBJECTIVE

RNA sequencing (transcriptomics) is used to study biological pathways. However, the yield of data depends on comparing well-characterized cohorts. We compared tissue eosinophilia versus nasal polyp (NP) status as the metric to characterize transcriptomic mechanisms at play in eosinophilic and non-eosinophilic chronic rhinosinusitis (CRS) versus controls.

METHODS

RNA sequencing was conducted on sinonasal tissue samples of CRS and controls. Analyses were conducted based on polyp status [with nasal polyps (CRSwNP) and without nasal polyps (CRSsNP)] as well as tissue eosinophil levels per high power field (eos/hpf)[non-eosinophilic (<10 eos/hpf, neCRS) or eosinophilic (≥10 eos/hpf, eCRS)]. The yield of differentially expressed genes (DEGs) and biological pathways through Ingenuity Pathway Analysis (IPA) were compared.

RESULTS

CRS tissue differed from controls by 736 statistically significant DEGs. Both NP status and tissue eosinophilia were effective in differentiating CRS from controls and into two distinct subgroups. Statistically significant DEGs identified when comparing CRS by NP status were 60, whereas 110 DEGs were identified using eosinophil cutoff ≥10 and <10 eos/hpf. Additionally, heatmaps showed greater homogeneity within each CRS subgroup when analyzed by tissue eosinophilia versus NP status. On IPA, the IL-17 signaling pathway was significantly different only by tissue eosinophilia status, not NP status, being higher in CRS <10 eos/hpf.

CONCLUSION

Tissue eosinophilia is superior to an analysis by NP status for the study of CRS transcriptome by RNA sequencing in identifying DEGs. Classification of CRS samples by eosinophil counts agnostic of NP status may offer advantageous insights into CRS pathogenetic mechanisms.

LEVEL OF EVIDENCE

3 Laryngoscope, 133:2480-2489, 2023.

The causal association between peripheral blood eosinophils and nasal polyps: a Mendelian randomization study

OBJECTIVE

Observational studies suggested that peripheral blood eosinophils were associated with the risk of nasal polyps. However, these studies did not confirm the causality. This study aims to apply Mendelian randomization (MR) method to comprehensively assess the potential causal association between peripheral blood eosinophils and nasal polyps.

METHODS

Genetic instrumental variables were extracted from the largest available genome-wide association study (GWAS) of European participants, which were used to investigate the relationship between peripheral blood eosinophils and nasal polyps. The inverse variance weighted method, the MR Egger method, and the weighted median method were applied for this analysis. MR-Egger intercept tests, leave-one-out analyses, and funnel plots were performed for the sensitivity analysis.

RESULTS

With the inverse variance weighted method, the MR analysis suggested that there was a significant difference between peripheral blood eosinophils and the risk of nasal polyps (ukb-a-97, OR 1.004, 95% CI 1.003-1.005, p < 0.001; ukb-a-541, OR 1.005, 95% CI 1.004-1.006, p < 0.001; ukb-b-7211, OR 1.004, 95% CI 1.003-1.005, p < 0.001; ukb-b-8425, OR 1.004, 95% CI 1.003-1.005, p < 0.001; finn-b-J10_NASALPOLYP, OR 3.089, 95% CI 2.537-3.761, p < 0.001). Consistent results were also proved by using the weighted median method and the MR Egger method.

CONCLUSIONS

Our findings reveal the causal effect of peripheral blood eosinophils on the increased risk of nasal polyps.

MEX3B inhibits collagen production in eosinophilic nasal polyps by downregulating epithelial cell TGFBR3 mRNA stability

Although the expression of Mex3 RNA-binding family member B (MEX3B) is upregulated in human nasal epithelial cells (HNECs) predominately in the eosinophilic chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP) subtype, its functions as an RNA binding protein in airway epithelial cells remain unknown. Here, we revealed the role of MEX3B based on different subtypes of CRS and demonstrated that MEX3B decreased the TGF-β receptor III (TGFBR3) mRNA level by binding to its 3' UTR and reducing its stability in HNECs. TGF-βR3 was found to be a TGF-β2-specific coreceptor in HNECs. Knocking down or overexpressing MEX3B promoted or inhibited TGF-β2-induced phosphorylation of SMAD2 in HNECs, respectively. TGF-βR3 and phosphorylated SMAD2 levels were downregulated in CRSwNP compared with controls and CRS without nasal polyps with a more prominent downregulation in the eosinophilic CRSwNP. TGF-β2 promoted collagen production in HNECs. Collagen abundance decreased and edema scores increased in CRSwNP compared with control, again more prominently in the eosinophilic type. Collagen expression in eosinophilic CRSwNP was negatively correlated with MEX3B but positively correlated with TGF-βR3. These results suggest that MEX3B inhibits tissue fibrosis in eosinophilic CRSwNP by downregulating epithelial cell TGFBR3 expression; consequently, MEX3B might be a valuable therapeutic target against eosinophilic CRSwNP.

Transcriptomic Differentiation of Phenotypes in Chronic Rhinosinusitis and Its Implications for Understanding the Underlying Mechanisms

Chronic rhinosinusitis (CRS) is a multifaceted disease with variable clinical courses and outcomes. We aimed to determine CRS-associated nasal-tissue transcriptome in clinically well-characterized and phenotyped individuals, to gain a novel insight into the biological pathways of the disease. RNA-sequencing of tissue samples of patients with CRS with polyps (CRSwNP), without polyps (CRSsNP), and controls were performed. Characterization of differently expressed genes (DEGs) and functional and pathway analysis was undertaken. We identified 782 common CRS-associated nasal-tissue DEGs, while 375 and 328 DEGs were CRSwNP- and CRSsNP-specific, respectively. Common key DEGs were found to be involved in dendritic cell maturation, the neuroinflammation pathway, and the inhibition of the matrix metalloproteinases. Distinct CRSwNP-specific DEGs were involved in NF-kβ canonical pathways, Toll-like receptor signaling, HIF1α regulation, and the Th2 pathway. CRSsNP involved the NFAT pathway and changes in the calcium pathway. Our findings offer new insights into the common and distinct molecular mechanisms underlying CRSwNP and CRSsNP, providing further understanding of the complex pathophysiology of the CRS, with future research directions for novel treatment strategies.

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.

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.

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.

The significant expression of TRPV3 in nasal polyps of eosinophilic chronic rhinosinusitis

BACKGROUND

The number of patients with eosinophilic chronic rhinosinusitis (ECRS) has been increasing in recent years in Japan. In ECRS, nasal polyps recur immediately after endoscopic sinus surgery. The molecular biological mechanism underlying the refractoriness of ECRS is unclear.

METHODS

Whole-transcriptome analysis with next-generation sequencing (RNA-seq) was conducted to investigate the molecular biological mechanism of ECRS. Real-time PCR, immunohistochemical staining, and immunofluorescence staining were performed to validate the results of RNA-seq.

RESULTS

RNA-seq analysis revealed that in the nasal polyps of ECRS, the levels of 3 transcripts were elevated significantly and those of 7 transcripts were diminished significantly. Among the genes encoding these transcripts, TRPV3 (transient receptor potential cation channel, subfamily V, member 3) was identified as the only gene that is highly expressed in ECRS nasal polyps but this gene's expression was not previously detected using DNA microarray analysis in peripheral blood eosinophils. TRPV3 is newly identified here as a gene transcribed in ECRS. Our analysis also revealed that TRPV3 was highly expressed in the infiltrating eosinophils and mucosal epithelium of the nasal polyps of ECRS, and further that the more severe the refractoriness was after surgery, the higher the TRPV3 expression was in nasal polyps.

CONCLUSIONS

TRPV3 might play a role in the refractoriness of ECRS. Additional studies are required to evaluate the function of TRPV3 in ECRS.

The role of interleukin-33 in chronic rhinosinusitis

RATIONALE

Interleukin (IL)-33, a new member of the IL-1 family, is constitutively expressed in epithelial tissues and lymphoid organs and plays an important role in the pathogenesis of allergic disease. However, the role of IL-33 in chronic rhinosinusitis with nasal polyps (CRSwNP) remains unclear.

OBJECTIVE

To investigate the role of IL-33 in the pathophysiology of CRSwNP.

METHODS

We investigated IL-33 expression and its cellular origins in the nasal polyps (NPs) of human subjects by immunohistochemistry (IHC), quantitative reverse transcription PCR (qRT-PCR), and multiplex cytokine assays. Correlations between IL-33 expression and other inflammatory markers were also explored. To investigate the role of IL-33 in CRSwNP, anti-IL-33 antibody was used in a murine model of CRS.

RESULTS

Uncinate process tissues from control (19), CRSsNP (61), CRSwNP (69) and NP tissues (71) were used in this study. Increased expression of IL-33 mRNA and protein in patients with CRSwNP compared with controls was observed. The concentration of IL-33 protein in CRSwNP was positively correlated with the number of neutrophils and the expression of several Th1 and Th17 inflammatory markers, including interferon (IFN)-γ, IL-1β, tumour necrosis factor (TNF)-α, IL-17A, IL-22, and various markers for neutrophil recruitment. However, protein levels of IL-5 and quantity of eosinophils were inversely correlated with levels of IL-33. The expression of tissue inhibitor of metalloproteinase (TIMP)-1 was negatively correlated with IL-33 protein levels, while the expression of matrix metalloproteinase (MMP)-2 and MMP-9 was positively correlated with IL-33 protein levels. In animal studies, IL-33 expression was upregulated in the CRSwNP group compared with controls. Anti-IL-33 treatment reduced the thickness of oedematous mucosa, subepithelial collagen deposition, and infiltration of neutrophils, but infiltration of eosinophils was not reduced. This treatment also inhibited the expression of neutrophilic inflammatory cytokines, but not IL-4. In addition, the expression of intracellular adhesion molecule 1, vascular adhesion molecule 1 and CXCL-2 in the nasal mucosa was suppressed in mice treated with anti-IL-33 antibody.

CONCLUSIONS

Our data suggest a role for IL-33 in the pathogenesis of CRSwNP via neutrophil recruitment. Therefore, anti-IL-33 may provide a new treatment strategy to target infiltrating neutrophils in CRSwNP.

Is Nasal Polyposis Related to Levels of Serum Vitamin D and Vitamin D Receptor Gene Expression?

BACKGROUND Nasal polyposis (NP) is the most frequent cause of nasal masses. Despite considerable research on the subject, its etiology has not been fully elucidated, and effective treatment methods have not been developed. Some etiological factors causing low or high expression of genes in genetically predisposed individuals may play a role in the pathogenesis of the disease. The purpose of this study was to assess the relation between levels of vitamin D receptor (VDR) gene expression and serum vitamin D with NP. MATERIAL AND METHODS The study included 46 subjects with NP (NP group) and 40 volunteers (control group). Nasal polyp tissue samples were taken from the NP group and nasal mucosa samples were taken from the control group. Levels of VDR gene expression in the tissue samples were assessed using the real-time polymerase chain reaction (RT-PCR) method. RESULTS Mean serum 25(OH)D levels were 13.38±14.08 ng/ml in the NP group and 10.57±6.44 ng/ml in the control group (p=0.249). VDR gene expression was present in 17.5% of the NP group and 3.3% of the control group, and the difference between the 2 groups was statistically significant (likelihood ratio χ²=3.887; p=0.049). CONCLUSIONS This is the first study to assess levels of VDR gene expression in subjects with NP. Our results suggest that VDR gene expression may be associated with the pathogenesis or progression of NP.

Gene-environment interactions between ERCC2, ERCC3, XRCC1 and cadmium exposure in nasal polyposis disease

Gene-environment interactions have long been known to play an important role in complex disease aetiology, such as nasal polyposis (NP). The present study supports the concept that DNA repair gene polymorphisms play critical roles in modifying individual susceptibility to environmental diseases. In fact, we investigated the role of polymorphisms in DNA repair genes and cadmium as risk factors for Tunisian patients with NP. To the best of our knowledge, this is the first report on the impact of combined effects of cadmium and ERCC3 7122 A>G (rs4150407), ERCC2 Lys751Gln (rs13181) and XRCC1 Arg399Gln (rs25487) genes in the susceptibility to NP disease. Significant associations between the risk of developing NP disease and ERCC2 [odds ratio (OR) = 2.0, 95 % confidence interval (CI) = 1.1-3.7, p = 0.023] and ERCC3 (OR = 2.2, 95 % CI = 1.2-4.1, p = 0.013) genotypes polymorphisms were observed. Blood concentrations of Cd in NP patients (2.2 μg/L) were significantly higher than those of controls (0.5 μg/L). A significant interaction between ERCC3 (7122 A>G) polymorphism and blood-Cd levels (for the median of blood-Cd levels: OR = 3.8, 95 % CI = 1.3-10.8, p = 0.014 and for the 75th percentiles of blood-Cd levels: OR = 2.7, 95 % CI = 1.1-7.2, p = 0.041) was found in association with the risk of NP disease. In addition, when we stratified ERCC2, ERCC3 and XRCC1 polymorphism genotypes by the median and 75th percentiles of blood-Cd levels, we found also significant interactions between ERCC2 (Lys751Gln) and ERCC3 (7122 A>G) genotypes polymorphism and this metal in association with NP disease. However, no interaction was found between XRCC1 (Arg399Gln) polymorphism genotypes and Cd in association with NP disease.

Chronic Rhinosinusitis with Nasal Polyps

Chronic rhinosinusitis with nasal polyps (CRSwNP) is an important clinical entity diagnosed by the presence of both subjective and objective evidence of chronic sinonasal inflammation. Symptoms include anterior or posterior rhinorrhea, nasal congestion, hyposmia, and/or facial pressure or pain that last for a duration of more than 12 weeks. Nasal polyps are inflammatory lesions that project into the nasal airway, are typically bilateral, and originate from the ethmoid sinus. Males are more likely to be affected than females, but no specific genetic or environmental factors have been strongly linked to the development of this disorder to date. CRSwNP is frequently associated with asthma and allergic rhinitis, but the cellular and molecular mechanisms that contribute to the clinical symptoms are not fully understood. Defects in the sinonasal epithelial cell barrier, increased exposure to pathogenic and colonized bacteria, and dysregulation of the host immune system are all thought to play prominent roles in disease pathogenesis. Additional studies are needed to further explore the clinical and pathophysiological features of CRSwNP so that biomarkers can be identified and novel advances can be made to improve the treatment and management of this disease.

Expression Profile of Immune-Associated Genes in Nasal Polyps

Objectives:

We performed this study to investigate the expression profile of immune-associated genes and to probe the role of related genes in the immune pathogenesis of nasal polyps.

Methods:

Microarray analysis was used to find the expression profile of 491 immune-associated genes in nasal polyps. In validation studies, immunohistochemical staining and Western blot analysis were used to detect interleukin (IL)–17 and IL-17 receptor (IL-17R) in nasal polyps and controls.

Results:

Eighty-seven genes were differentially expressed in the immune-associated gene profile of nasal polyps, and 15 genes showed differential expression in both chips. In nasal polyp tissues, IL-17 was expressed mainly in the cytoplasm of plasma cells and to a lesser degree in the prickle cell layer of the epithelium and the acinus of the serous gland. In turbinates, IL-17 was also expressed in the same location, but the expression of IL-17 in nasal polyps and that in turbinates differed significantly (p > .05). Both IL-17 and IL-17R displayed specific bands in nasal polyps and turbinates, but the bands of IL-17 and IL-17R in nasal polyps were stronger than those in turbinates.

Conclusions:

The differentially expressed genes in immune-associated gene chips will provide clues about, and a theoretical foundation for, the pathogenesis of nasal polyps. Furthermore, IL-17 may play an important role in the occurrence of nasal polyps by overexpression.

Polymorphism between Loci for Human Leukocyte Antigens DR and DQ in Patients with Nasal Polyps

Objectives:

We explored a potential association between nasal polyps (NPs) and polymorphism at loci for human leukocyte antigen (HLA) DR and HLA-DQ.

Methods:

Polymorphism at loci HLA-DR and HLA-DQ were examined in 30 patients with NPs and in 81 healthy subjects by use of the polymerase chain reaction-sequence specific primer method.

Results:

HLA-DR16, HLA-DQ8, and HLA-DQ9 were found to be significantly associated with NPs. HLA-DR16, HLA-DQ8, and HLA-DQ9 specificities were found at higher frequencies in patients with NPs than in control subjects (5% versus 0.62%, RR = 8.9, p = .03; 10% versus 2.47%, RR = 4.81, p = .01; and 20% versus 6.18%, RR = 4.73%, p = .001; respectively). In contrast, HLA-DQ7 was found at lower frequencies in patients with NPs than in controls (10% versus 20.37%, RR = 0.36, p = .04).

Conclusions:

We conclude that HLA-DR16, HLA-DQ8, and HLA-DQ9 represent potential susceptibility determinants and that HLA-DQ7 might confer resistance in nasal polyps.