Mucosal LTE4, PGD2 and 15(S)-HETE as potential prognostic markers for polyp recurrence in chronic rhinosinusitis

BACKGROUND

Altered biosynthesis of eicosanoids is linked to type 2 inflammation in chronic rhinosinusitis with nasal polyps (CRSwNP), but their role in recalcitrant NPs is unclear.

OBJECTIVES

We sought to identify endotypes that are linked to recalcitrant CRSwNP, based on eicosanoids, their biosynthetic enzymes, and receptors as well as cytokines and the presence of eosinophils and mast cells in recurrent NPs.

METHODS

Mucosal tissue collected at the time of sinus surgery from 54 patients with CRSwNP and 12 non-CRS controls were analysed for leukotriene (LT) E4, prostaglandin (PG) D2, 15(S)-hydroxyeicosatetraenoic acid (15(S)-HETE) and 17 cytokines with ELISAs and Bio-Plex immunoassays. Patient subgroups were identified by cluster analysis and the probability of NP recurrence were tested with logistic regression analyses. Gene expressions were analysed with qPCR. Tryptase and eosinophil-derived neurotoxin (EDN) were measured with ELISAs as indications of the presence of mast cells and eosinophils, respectively.

RESULTS

Clustering of patients showed that an inflammatory signature characterised by elevated LTE4, PGD2, 15(S)-HETE and IL-13 was associated with NP recurrence. Previous NP surgery as well as aspirin-exacerbated respiratory disease were significantly more common among these patients. Expression of cyclooxygenase 1 was the only gene associated with NP recurrence. Levels of EDN, but not tryptase, were significantly higher in patients with recurrent NPs.

CONCLUSION

Distinguishing endotypes that include LTE4, PGD2, 15HETE and conventional biomarkers of type 2 inflammation could help predict recurrent nasal polyposis and thus identify cases of recalcitrant CRSwNP.

Identification of hub genes associated with neutrophils in chronic rhinosinusitis with nasal polyps

Neutrophil infiltration plays a key role in the pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP). However, pertinent mechanisms remain poorly elucidated. Here, we obtained the data from gene expression omnibus (GEO) and gene set enrichment analysis (GSEA) to identify and validate neutrophil-associated hub genes in CRSwNP. We found that four neutrophil-associated hub genes, namely ICAM1, IL-1β, TYROBP, and BCL2A1, were markedly upregulated and positively correlated with neutrophil infiltration levels in patients with CRSwNP. Subsequently, this was confirmed by real-time quantitative PCR. In conclusion, we identified the role of neutrophil infiltration in the pathophysiology of CRSwNP, which may be the potential targets for the diagnosis and treatment of CRSwNP.

Air pollution, genetic factors, and chronic rhinosinusitis: A prospective study in the UK Biobank

BACKGROUND

Chronic rhinosinusitis (CRS) is a prevalent upper respiratory condition that manifests in two primary subtypes: CRS with nasal polyps (CRSwNP) and CRS without nasal polyps (CRSsNP). While previous studies indicate a correlation between air pollution and CRS, the role of genetic predisposition in this relationship remains largely unexplored. We hypothesized that higher air pollution exposure would lead to the development of CRS, and that genetic susceptibility might modify this association.

METHODS

This cohort study involving 367,298 adult participants from the UK Biobank, followed from March 2006 to October 2021. Air pollution metrics were estimated at residential locations using land-use regression models. Cox proportional hazard models were employed to explore the associations between air pollution exposure and CRS, CRSwNP, and CRSsNP. A polygenic risk score (PRS) was constructed to evaluate the joint effect of air pollution and genetic predisposition on the development of CRS.

RESULTS

We found that the risk of CRS increased under long-term exposure to PM2.5 [the hazard ratios (HRs) with 95 % CIs: 1.59 (1.26-2.01)], PM10 [1.64 (1.26-2.12)], NO2 [1.11 (1.04-1.17)], and NOx [1.18 (1.12-1.25)], respectively. These effects were more pronounced among participants with CRSwNP, although the differences were not statistically significant. Additionally, we found that the risks for CRS and CRSwNP increased in a graded manner among participants with higher PRS or higher exposure to PM2.5, PM10, or NOx concentrations. However, no multiplicative or additive interactions were observed.

CONCLUSIONS

Long-term exposure to air pollution increases the risk of CRS, particularly CRSwNP underscoring the need to prioritize clean air initiatives and environmental regulations.

Small extracellular vesicles facilitate epithelial-mesenchymal transition in chronic rhinosinusitis with nasal polyps via the miR-375-3p/QKI axis

BACKGROUND

Epithelial-mesenchymal transition (EMT) plays a crucial role in the pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP). However, the involvement of small extracellular vesicles (sEVs) in EMT and their contributions to CRSwNP has not been extensively investigated.

METHODS

SEVs were isolated from nasal mucosa through ultracentrifugation. MicroRNA sequencing and reverse-transcription quantitative polymerase chain reaction were employed to analyze the differential expression of microRNAs carried by sEVs. Human nasal epithelial cells (hNECs) were used to assess the EMT-inducing effect of sEVs/microRNAs. EMT-associated markers were detected by western blotting and immunofluorescence. Dual-luciferase reporter assay was performed to determine the target gene of miR-375-3p. MicroRNA mimic, lentiviral, and plasmid transduction were used for functional experiments.

RESULTS

In line with the greater EMT status in eosinophilic CRSwNP (ENP), sEVs derived from ENP (ENP-sEVs) could induce EMT in hNECs. MiR-375-3p was elevated in ENP-sEVs compared to that in control and nonENP. MiR-375-3p carried by ENP-sEVs facilitated EMT by directly targeting KH domain containing RNA binding (QKI) at seed sequences of 913-919, 1025-1033, and 2438-2444 in 3’-untranslated region. Inhibition of QKI by miR-375-3p overexpression promoted EMT, which could be reversed by restoration of QKI. Furthermore, the abundance of miR-375-3p in sEVs was closely correlated with the clinical symptom score and disease severity.

CONCLUSIONS

MiR-375-3p-enriched sEVs facilitated EMT by suppressing QKI in hNECs. The association of miR-375-3p with disease severity underscores its potential as both a diagnostic marker and a therapeutic target for the innovative management of CRSwNP.

Low levels of miR-143-3p are associated with severe chronic rhinosinusitis with nasal polyps

microRNAs (miRNAs) are small, single-stranded, non-coding RNA molecules that regulate post-transcriptional gene expression. Accumulating evidence suggests their involvement in regulating various biological and pathological processes, including inflammation. Studies have revealed distinct expression patterns of miRNAs in Chronic Rhinosinusitis with (CRSwNP) and without (CRSsNP) nasal polyps (1). Specifically, miR-155 and miR-21 have been observed to be upregulated in CRSwNP, increasing and attenuating the expression of pro-inflammatory cytokines, respectively (2,3). Conversely, the downregulation of miR-34, miR-449, and members of the miR-200 family has been associated with impaired ciliogenesis and the regulation of epithelial-mesenchymal transition, respectively (4,5). Nonetheless, the direct role of miRNAs in CRSwNP is still being investigated.

Recessively Inherited Deficiency of Secreted WFDC2 (HE4) Causes Nasal Polyposis and Bronchiectasis

Rationale: Bronchiectasis is a pathological dilatation of the bronchi in the respiratory airways associated with environmental or genetic causes (e.g., cystic fibrosis, primary ciliary dyskinesia, and primary immunodeficiency disorders), but most cases remain idiopathic. Objectives: To identify novel genetic defects in unsolved cases of bronchiectasis presenting with severe rhinosinusitis, nasal polyposis, and pulmonary Pseudomonas aeruginosa infection. Methods: DNA was analyzed by next-generation or targeted Sanger sequencing. RNA was analyzed by quantitative PCR and single-cell RNA sequencing. Patient-derived cells, cell cultures, and secretions (mucus, saliva, seminal fluid) were analyzed by Western blotting and immunofluorescence microscopy, and mucociliary activity was measured. Blood serum was analyzed by electrochemiluminescence immunoassay. Protein structure and proteomic analyses were used to assess the impact of a disease-causing founder variant. Measurements and Main Results: We identified biallelic pathogenic variants in WAP four-disulfide core domain 2 (WFDC2) in 11 individuals from 10 unrelated families originating from the United States, Europe, Asia, and Africa. Expression of WFDC2 was detected predominantly in secretory cells of control airway epithelium and also in submucosal glands. We demonstrate that WFDC2 is below the limit of detection in blood serum and hardly detectable in samples of saliva, seminal fluid, and airway surface liquid from WFDC2-deficient individuals. Computer simulations and deglycosylation assays indicate that the disease-causing founder variant p.Cys49Arg structurally hampers glycosylation and, thus, secretion of mature WFDC2. Conclusions: WFDC2 dysfunction defines a novel molecular etiology of bronchiectasis characterized by the deficiency of a secreted component of the airways. A commercially available blood test combined with genetic testing allows its diagnosis.

[Single-cell transcriptomic sequencing coupled with Mendelian randomization analysis elucidates the pivotal role of CTSC in chronic rhinosinusitis]

Objective: To investigate the molecular mechanisms of chronic rhinosinusitis (CRS), to identify key cell subgroups and genes, to construct effective diagnostic models, and to screen for potential therapeutic drugs. Methods: Key cell subgroups in CRS were identified through single-cell transcriptomic sequencing data. Essential genes associated with CRS were selected and diagnostic models were constructed by hdWGCNA (high dimensional weighted gene co-expression network analysis) and various machine learning algorithms. Causal inference analysis was performed using Mendelian randomization and colocalization analysis. Potential therapeutic drugs were identified using molecular docking technology, and the results of bioinformatics analysis were validated by immunofluorescence staining. Graphpad Prism, R, Python, and Adobe Illustrator software were used for data and image processing. Results: An increased proportion of basal and suprabasal cells was observed in CRS, especially in eosinophilic CRS with nasal polyps (ECRSwNP), with P=0.001. hdWGCNA revealed that the "yellow module" was closely related to basal and suprabasal cells in CRS. Univariate logistic regression and LASSO algorithm selected 13 key genes (CTSC, LAMB3, CYP2S1, TRPV4, ARHGAP21, PTHLH, CDH26, MRPS6, TENM4, FAM110C, NCKAP5, SAMD3, and PTCHD4). Based on these 13 genes, an effective CRS diagnostic model was developed using various machine learning algorithms (AUC=0.958). Mendelian randomization analysis indicated a causal relationship between CTSC and CRS (inverse variance weighted: OR=1.06, P=0.006), and colocalization analysis confirmed shared genetic variants between CTSC and CRS (PPH4/PPH3>2). Molecular docking results showed that acetaminophen binded well with CTSC (binding energy:-5.638 kcal/mol). Immunofluorescence staining experiments indicated an increase in CTSC+cells in CRS. Conclusion: This study integrates various bioinformatics methods to identify key cell types and genes in CRS, constructs an effective diagnostic model, underscores the critical role of the CTSC gene in CRS pathogenesis, and provides new targets for the treatment of CRS.

Identification of core gene in chronic rhinosinusitis with nasal polyps and correlations with inflammation-related genes

OBJECTIVE

Our aim in this study is to identify the core genes of chronic rhinosinusitis with nasal polyps and analyze the correlations between it and inflammation-related genes.

METHODS

GSE72713 dataset containing gene expression data of ECRSwNP, nonECRSwNP and healthy samples was obtained from Gene Expression Omnibus (GEO) and filtered by limma to identify DEGs among three groups, then the functions and correlated pathways of DEGs were analyzed using GO and KEGG. The core DEGs were selected by the intersection of DEGs and the PPI network was constructed via STRING. The correlations between the expression levels of CRSwNP core gene and inflammation-related genes were analyzed via the Mann-Whitney U test.

RESULTS

The DEGs among ECRSwNP, nonECRSwNP, and CTRL were filtered respectively, and enrichment analysis showed they were associated with olfaction and/or immune responses. The PPI network was constructed by 7 core DEGs obtained via the intersection among three groups, and ALOX15 was confirmed as the core gene in the network. Subsequently, the correlations between the expression levels of ALOX15 and inflammation-related genes were illustrated.

CONCLUSION

In this study, the core gene ALOX15 was selected from the DEGs among ECRSwNP, nonECRSwNP, and CTRL. IL5, IL1RL1, and IL1RAP were found to exhibit a significant positive correlation with ALOX15.

LEVEL OF EVIDENCE

Level 3.

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.