Will we ever cure nasal polyps?

Multi-Disciplinary Expert Perspective on the Management of Type 2 Inflammation-Driven Severe CRSwNP: A Brief Overview of Pathophysiology and Recent Clinical Insights

Severe chronic rhinosinusitis with nasal polyposis (CRSwNP) is a disabling airway disease that significantly impacts patients' lives through the severity of symptoms, the need for long-term medical treatment and the high risk of recurrence post-surgery. Biological agents targeting type 2 immune responses underlying the pathogenesis of CRSwNP have shown effectiveness in reducing polyp size and eosinophilic infiltrate, and in decreasing the need for additional sinus surgeries. However, despite recent progress in understanding and treating the disease, type 2 inflammation-driven severe CRSwNP continues to pose challenges to clinical management due to several factors such as persistent inflammation, polyp recurrence, heterogeneity of disease, and comorbidities. This article presents the findings of a scientific discussion involving a panel of ear, nose and throat (ENT) specialists and pulmonologists across Sweden and Finland. The discussion aimed to explore current management practices for type 2 inflammation-driven severe CRSwNP in the Nordic region. The main topics examined encompassed screening and referral, measurements of disease control, treatment goals, and future perspectives. The experts emphasized the importance of a collaborative approach in the management of this challenging patient population. The discussion also revealed a need to broaden treatment options for patients with type 2 inflammation-driven CRSwNP and comorbid conditions with shared type 2 pathophysiology. In light of the supporting evidence, a shift in the disease model from the presence of polyps to that of type 2 inflammation may be warranted. Overall, this discussion provides valuable insights for the scientific community and can potentially guide the future management of CRSwNP.

Surgical treatment of bovine nasal granuloma and an allergological exploration

Nasal granuloma in cattle results from inflammation within, and attendant proliferation of, the nasal mucosa possibly in response to an allergic response. However, the relationship between nasal granuloma and allergies remains unclear. Furthermore, severe cases have a poor prognosis because there is currently no effective treatment. Herein, we report three cases of nasal granuloma with severe stertorous breathing that were treated surgically. We also conducted an allergological exploration. Following surgical removal clinical signs did not recur in two of the three cases; however, stertorous breathing persisted in one case, and the cow was sacrificed 4 months later. A histopathological examination revealed that all nasal granulomas featured varying infiltrations of macrophages eosinophils, mast cells, and lymphocytes. The number of mast cells and the proportion of these cells that had degranulated were significantly higher in the granulomas than in normal nasal mucosae. In addition, serum histamine levels were higher in nasal granuloma cases than in normal cows, although serum immunoglobulin E levels were similar, and lymphocyte infiltration in the submucosal layer suggested type I and type IV allergies. Collectively, the results indicate the efficacy of complete surgical curettage for the treatment of allergic nasal granuloma in cattle. Further studies are required to identify the causes and risk factors of allergic nasal granuloma in cows.

Remodeling of Paranasal Sinuses Mucosa Functions in Response to Biofilm-Induced Inflammation

Rhinosinusitis (RS) is an acute (ARS) or chronic (CRS) inflammatory disease of the nasal and paranasal sinus mucosa. CRS is a heterogeneous condition characterized by distinct inflammatory patterns (endotypes) and phenotypes associated with the presence (CRSwNP) or absence (CRSsNP) of nasal polyps. Mucosal barrier and mucociliary clearance dysfunction, inflammatory cell infiltration, mucus hypersecretion, and tissue remodeling are the hallmarks of CRS. However, the underlying factors, their priority, and the mechanisms of inflammatory responses remain unclear. Several hypotheses have been proposed that link CRS etiology and pathogenesis with host (eg, "immune barrier") and exogenous factors (eg, bacterial/fungal pathogens, dysbiotic microbiota/biofilms, or staphylococcal superantigens). The abnormal interplay between these factors is likely central to the pathophysiology of CRS by triggering compensatory immune responses. Here, we discuss the role of the sinonasal microbiota in CRS and its biofilms in the context of mucosal zinc (Zn) deficiency, serving as a possible unifying link between five host and "bacterial" hypotheses of CRS that lead to sinus mucosa remodeling. To date, no clear correlation between sinonasal microbiota and CRS has been established. However, the predominance of Corynebacteria and Staphylococci and their interspecies relationships likely play a vital role in the formation of the CRS-associated microbiota. Zn-mediated "nutritional immunity", exerted via calprotectin, alongside the dysregulation of Zn-dependent cellular processes, could be a crucial microbiota-shaping factor in CRS. Similar to cystic fibrosis (CF), the role of SPLUNC1-mediated regulation of mucus volume and pH in CRS has been considered. We complement the biofilms' "mechanistic" and "mucin" hypotheses behind CRS pathogenesis with the "structural" one - associated with bacterial "corncob" structures. Finally, microbiota restoration approaches for CRS prevention and treatment are reviewed, including pre- and probiotics, as well as Nasal Microbiota Transplantation (NMT).

Prioritization of nasal polyp-associated genes by integrating GWAS and eQTL summary data

Background: Nasal polyps (NP) are benign inflammatory growths of nasal and paranasal sinus mucosa that can substantially impair patients' quality of life by various symptoms such as nasal obstruction, insomnia, and anosmia. NP often relapse even after surgical treatment, and the curative therapy would be challenging without understanding the underlying mechanisms. Genome wide association studies (GWASs) on NP have been conducted; however, few genes that are causally associated with NP have been identified. Methods: We aimed to prioritize NP associated genes for functional follow-up studies using the summary data-based Mendelian Randomization (SMR) and Bayesian colocalization (COLOC) methods to integrate the summary-level data of the GWAS on NP and the expression quantitative trait locus (eQTL) study in blood. We utilized the GWAS data including 5,554 NP cases and 258,553 controls with 34 genome-wide significant loci from the FinnGen consortium (data freeze 8) and the eQTL data from 31,684 participants of predominantly European ancestry from the eQTLGen consortium. Results: The SMR analysis identified several genes including TNFRSF18, CTSK, and IRF1 that were associated with NP due to not linkage but pleiotropy or causality. The COLOC analysis strongly suggested that these genes and the trait of NP were affected by shared causal variants, and thus were colocalized. An enrichment analysis by Metascape suggested that these genes might be involved in the biological process of cellular response to cytokine stimulus. Conclusion: We could prioritize several NP associated genes including TNFRSF18, CTSK, and IRF1 for follow-up functional studies in future to elucidate the underlying disease mechanisms.

Nasal polyposis from cystic fibrosis in children - the experience of a single center

BACKGROUND

Cystic fibrosis (CF) is the most common monogenic disease, characterized by clinically notable polymorphism. Respiratory disease is the main factor that influences the disease outcome and prognosis of the patient with CF, bacterial infections being responsible for severe exacerbations and rhinosinusitis a difficult complication, besides lung disease.

AIM

The aim of the paper was to present a case series of CF-associated nasal polyposis and our management experience, providing new data for nasal and sinus complications.

PATIENTS, MATERIALS AND METHODS

Patients attending the National Cystic Fibrosis Center, Timişoara, Romania, were evaluated for nasal polyposis. Besides clinical examination, endoscopy, and computed tomography (CT) was performed for comprehensive evaluation. Patients with persistent symptoms or with complicated sinusitis underwent surgical approach.

RESULTS

Fourteen (18.18%) children were diagnosed with nasal polyposis and had surgery, with positive outcomes. One patient received Omalizumab for an associated, uncontrolled asthma with a subsequent substantial effect with the significant polyp reduction and lack of recurrence.

CONCLUSIONS

Even if extremely difficult to manage, complicated nasal polyposis CF related might have an improved outcome and better life quality.

Detection of Helicobacter Pylori in Nasal Polyps: An Epidemiological Study

Many studies have described the detection of Helicobacter pylori (HP) in the nasal polyps; however, although gastroesophageal reflux has been associated with chronic rhinosinusitis and nasal polyps development, the role of HP remains unclear. Our aim was to describe the prevalence of HP detection in nasal polyps and its association with gastric HP infection and gastroesophageal reflux dsease (GERD). The prospective study involved 36 patients with nasal polyps, who underwent to endoscopic surgery removal of nasal polyps. Before surgical procedure all patients were tested for gastric HP infection by 13 C-urea breath test, while tissue samples from nasal polyps were tested for HP detection, using rapid urease test (CLO test) and histological examination with Giemsa stain. All patients were asked about GERD-related symptoms. HP in nasal polyps was detected in 9 out of 36 patients (25%) using histological examination with Giemsa stain, while the detection rate of HP was 30.5% (11/36) using CLO test. Furthermore, 28 out of 36 patients (77.7%) had gastric HP infection. All patients with HP colonization in nasal polyps had gastric HP infection and all patients with HP in nasal polyps reported symptoms related to GERD. HP was detected in approximately one out of three patients in nasal polyps, while all patients with HP detection in nasal polyps had concurrently gastric HP infection and reported GERD-related symptoms, suggesting a gastro-nasal route of HP.

Transcription Factor Specificity Protein 1 Regulates Inflammation and Fibrin Deposition in Nasal Polyps Via the Regulation of microRNA-125b and the Wnt/β-catenin Signaling Pathway

Nasal polyps (NPs) are multifactorial soft growths inside the nasal passages and are associated with chronic inflammation that originate from the nasal and paranasal sinus mucosae. This study focused on the role of microRNA (miR)-125b and the molecules associated with NP development. Differentially expressed miRNAs between nasal tissues from patients with chronic rhinosinusitis (CRS) with NP (CRSwNP) and CRS without NP (CRSsNP) were screened using microarray analysis. A murine model of CRSwNP was established. The expression of miR-125b in murine tissues was examined using reverse transcription quantitative polymerase chain reaction. Candidate upstream regulators of miR-125b were predicted using bioinformatics tools, and the binding relationship between specificity protein 1 (Sp1) and miR-125b was validated using luciferase and chromatin immunoprecipitation assays. Altered expression of Sp1 and miR-125b was induced to evaluate their relevance to the progression of NPs. miR-125b expression was significantly upregulated in NP tissues from patients with CRSwNP. Sp1 was confirmed as an upstream regulator that promotes miR-125b transcription in NPs. Overexpression of Sp1 reduced levels of d-dimer (an indicator of fibrinogen degradation products) and tissue-type plasminogen activator (t-PA) but increased eosinophil cationic protein and peroxidase levels, as well as the levels of inflammatory factors interleukin-5 (IL-5) and IL-8 in murine NP tissues. However, these trends were reversed after miR-125b downregulation. Sp1 and miR-125b were found to activate the Wnt/β-catenin signaling pathway in NPs. This study demonstrated that Sp1, an upstream transcription factor of miR-125b, accumulates on the miR-125b promoter to activate its transcription, which induces inflammation and fibrin deposition in NP by activating the Wnt/β-catenin axis.

Establishment and genetic characterization of cell lines derived from proliferating nasal polyps and sinonasal inverted papillomas

To better understand the pathogenesis of nasal polyps (NPs) and sinonasal inverted papillomas (SIPs), we aimed to establish cell lines from fresh tissues of NPs and SIPs and characterize them. Primary cell cultures were obtained from two NP tissues (NP2 and NP3) and one SIP tissue (IP4). All the cells were polygonal in shape, expressed cytokeratin 14, and had normal diploid chromosome status. HPV58 DNA was detected in NP3. To obtain immortal primary cells, NP2 and IP4 cells were transduced with a combination of mutant CDK4, cyclinD1 and TERT. These cells were thereafter named NP2/K4DT and IP4/K4DT, respectively. HPV58-positive NP3 cells were transduced with TERT alone, the resulting cells named NP3/T. Phenotypic and genotypic identity of original tissues and derived cells was investigated. All the cell cultures with transgenes were confirmed to be derived from their parental cells and primary tumor tissues by analysis of short tandem repeats (STR) and maintained in vitro growth, genetic profiles and gene expression characteristics of the primary cells. These virtually immortalized cells, as well as the primary cells, have potential as in vitro models for studying the pathogenesis of NPs and SIPs and for preclinical study to develop new therapeutic agents.

Defining the Efficacy of Omalizumab in Nasal Polyposis: A POLYP 1 and POLYP 2 Subgroup Analysis

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a heterogeneous disease with variable underlying pathophysiologies. Numerous patient factors have been linked to differences in disease severity, control, and response to treatment, including asthma status, aspirin sensitivity, previous sinonasal surgery, and blood eosinophil levels.

OBJECTIVE

The present study examines the efficacy of the anti-immunoglobulin E therapy, omalizumab, versus placebo in patients with CRSwNP from the replicate POLYP 1 (NCT03280550) and POLYP 2 (NCT03280537) trials, grouped by inherent patient characteristics to determine the response to therapy.

METHODS

Patients in prespecified subgroups from POLYP 1 and POLYP 2 (studies pooled for analysis) were examined. Subgroups included blood eosinophil count at baseline (>300 or ≤300 cells/μL), previous sinonasal surgery (yes or no), asthma status (yes or no), and aspirin sensitivity status (yes or no). Subgroups were examined for subgroup-specific adjusted mean difference (95% confidence interval [CI]) (omalizumab-placebo) in change from baseline at week 24 in Nasal Congestion Score (NCS), Nasal Polyp Score (NPS), Sino-Nasal Outcome Test-22 (SNOT-22), Total Nasal Symptom Score (TNSS), and University of Pennsylvania Smell Identification Test (UPSIT).

RESULTS

Adjusted mean difference (95% CI) (omalizumab-placebo) in NCS, NPS, SNOT-22, TNSS, and UPSIT change from baseline at week 24 consistently favored omalizumab treatment over placebo in patients with blood eosinophil count >300 and ≤300 cells/μL, with or without previous sinonasal surgery, asthma, and aspirin sensitivity.

CONCLUSION

Together, these data suggest broad efficacy of omalizumab across clinical and patient-reported outcomes in patients with CRSwNP, independent of the underlying patient factors examined, including those with high eosinophil levels and those who have undergone previous surgery, which are associated with high recurrence.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifiers: POLYP 1: ClinicalTrials.gov identifier NCT03280550 (https://clinicaltrials.gov/ct2/show/NCT03280550); POLYP 2: ClinicalTrials.gov identifier NCT03280537 (https://clinicaltrials.gov/ct2/show/NCT03280537).

Effect of oral steroids on olfactory function in chronic rhinosinusitis with nasal polyps

AIMS

The present study aimed to investigate the effects of oral steroids on olfactory disturbances in patients with chronic rhinosinusitis with nasal polyps (CRSwNP).

MATERIAL AND METHODS

This is a prospective randomized non-blinded study. Selected CRSwNP patients (n=140), with hyposmia, were devided into two groups; group A received a 7-day course of oral steroids with a 12-weeks course of nasal steroids and douching; group B received a 12-weeks course of nasal steroids and douching. Assessment included Sniffin' Sticks scores, visual analogue scale score for olfaction and discomfort (VASsmell, VASdis), the Sinonasal Outcome Test-22, Greek-version (SNOT22-Gr) and the endoscopic appearance (EAS).

OBJECTIVES

The main objective was to compare the olfactory effect of the different therapy in group A and group B, at 2, 12 and 24 weeks. Accessory objectives included the comparison of EAS, VASdis and SNOT22-Gr between groups, the evaluation of the therapeutic outcome duration, and, the investigation of potential correlation between the evaluated parameters.

RESULTS

The 2-weeks evaluation showed a significant statistical difference (P<0.001) for all parameters except VASdis. Olfactory outcomes (Sniffin' Sticks and VASsmell scale scores) were found significantly better in group A at the 24-weeks evaluation (P<0.001). Within groups, the therapeutic result remained stable between the 12-weeks and 24-weeks evaluation (P>0.05). Sniffin' Sticks score was strongly correlated at 12-weeks evaluation with EAS (rho=0.58, P<0.001).

CONCLUSION

Our results suggest that a combination treatment of oral and nasal steroids in well-selected patients with CRSwNP may result in early olfaction restoration with a possible long-term effect.

Latest advances in chronic rhinosinusitis with nasal polyps endotyping and biomarkers, and their significance for daily practice

The term chronic rhinosinusitis (CRS) comprises of an assortment of diseases that share a common feature: inflammation of the sinonasal mucosa. The phenotype classification of CRS, based on the presence of polyps, has failed to offer a curative treatment for the disease, particularly in refractory cases. Chronic rhinosinusitis with nasal polyps (CRSwNP) remains a challenging entity. Researchers have made efforts trying to characterize subtypes of the disease according to the endotypes, which are delineated by different immunological pathways, using biomarkers. Even if the inflammatory processes controlling CRSwNP are not fully understood, data suggested that the disease associated with a type 2 inflammatory mechanisms can be also linked to the type 1 or type 3 pathomechanism, being highly heterogeneous. Biomarkers for CRSwNP are proposed, such as: eosinophil count, cytokines, metalloproteinases, bitter and sweet taste receptors, and the nasal microbiome. For endotyping to be clinically applicable and simply determined, biomarkers referring to the intrinsic biomolecular mechanism still need to be found. Precision medicine is becoming the new standard of care, but innovative therapies such as biologics may be rather challenging for the clinicians in their daily practice. This new approach to CRSwNP implies patient selection and a simple algorithm for deciding the right treatment, easy to implement and adjust. Our review points out the ongoing new research on the pathophysiology of CRSwNP, biomarkers and treatment opportunities. It allows clinicians to keep abreast of current evidence-based knowledge and to individualize the management of CRSwNP, especially in refractory cases.