Residual nasal polyp tissue following dupilumab therapy is associated with periostin-associated fibrosis

PURPOSE

Dupilumab, an anti-interleukin-4 receptor alpha monoclonal antibody, is a new treatment for severe uncontrolled chronic rhinosinusitis with nasal polyps. However, data on the effect of dupilumab on histological changes in nasal polyp tissue are lacking. We aimed to investigate the effect of dupilumab on real-life clinical conditions and nasal polyp tissues from patients with eosinophilic chronic rhinosinusitis (ECRS), which is a refractory subtype.

METHODS

We conducted an open-label, prospective, observational, single-centre study on 63 patients with refractory ECRS on the basis of the criteria of the Japanese Epidemiological Survey of Refractory Eosinophilic Chronic Rhinosinusitis Study. These patients had a history of surgery and received dupilumab for 24 weeks. Patient-reported sinonasal symptoms, T&T olfactometry and nasal polyp scores were prospectively evaluated. In 23 patients with residual nasal polyps following dupilumab treatment, changes in systemic and local periostin expression, and total collagen deposition in nasal polyp tissues were investigated before and after dupilumab administration.

RESULTS

Dupilumab rapidly improved sinonasal symptoms and reduced the nasal polyp score 24 weeks after initiation. 40 (63.5%) patients had resolution of nasal polyps, but the reduction was limited in the remaining 23 (36.5%) patients. Periostin expression in serum and nasal lavage fluid was decreased, whereas periostin and the total collagen deposition area in subepithelial tissues in residual nasal polyps were enhanced after dupilumab administration.

CONCLUSION

Dupilumab improves sinonasal symptoms and reduces the nasal polyp score in refractory ECRS. Periostin-associated tissue fibrosis may be involved in the differential effect of dupilumab on nasal polyp reduction.

Matrix metalloproteinases and chronic rhinosinusitis with nasal polyposis. Unravelling a puzzle through a systematic review

BACKGROUND

The expression of metalloproteinases (MMPs) in chronic rhinosinusitis with nasal polyposis (CRSwNP) was reviewed in order to investigate their possible use as therapeutical targets and/or biomarkers.

METHODOLOGY

The differences between CRSwNP and normal controls or CRS without NP, as well as the effects of various treatments on MMPs, tissue inhibitors of MMPs (TIMPs) and MMP/TIMP ratios were considered as primary outcomes. Additional factors reported to affect MMP expression levels were noted as secondary outcomes. Data regarding inflammatory subtypes, patients’ clinical characteristics, controls, laboratory method(s) and origin of samples were also pooled. Studies on 10 or fewer patients or on specimens other than nasal and serum were excluded.

RESULTS

Forty-three studies were included. Tissue sample origin, allergic rhinitis, smoking, infection, medication intake and primary or recurrent disease should be considered as confounding factors for MMP levels. MMP-1 and -7 were consistently found to be significantly higher in CRSwNP patients than controls. CRSwNP endotypes with distinctly different inflammation patterns seem to present similar MMP-related remodelling patterns.

CONCLUSIONS

The existing literature has revealed several population and methodology related confounding factors and remains inconclusive regarding the roles of MMPs in CRSwNP pathophysiology and their possible clinical usefulness as biomarkers and therapeutical targets.

Targetable pathogenic mechanisms in nasal polyposis

Chronic rhinosinusitis with nasal polyps (CRSwNP) represents a challenging disease entity with significant rates of recurrence following appropriate medical and surgical therapy. Recent approval of targeted biologics in CRSwNP compels deeper understanding of underlying disease pathophysiology. Both of the approved biologics for CRSwNP modulate the type 2 inflammatory pathway, and the majority of drugs in the clinical trials pathway are similarly targeted. However, there remain multiple other pathogenic mechanisms relevant to CRSwNP for which targeted therapeutics already exist in other inflammatory diseases that have not been studied directly. In this article we summarize pathogenic mechanisms of interest in CRSwNP and discuss the results of ongoing clinical studies of targeted therapeutics in CRSwNP and other related human inflammatory diseases.

Pathological and therapeutic implications of eosinophil-derived semaphorin 4D in eosinophilic chronic rhinosinusitis

BACKGROUND

Eosinophilic chronic rhinosinusitis (ECRS) is a subtype of chronic rhinosinusitis. Clinical markers for ECRS disease activity and treatment strategies have not been sufficiently established. Although semaphorins are originally identified as neuronal guidance factors, it is becoming clear that they play key roles in immune regulation and inflammatory diseases.

OBJECTIVE

We sought to investigate the pathological functions and therapeutic potential of semaphorin 4D (SEMA4D) in ECRS.

METHODS

Serum soluble SEMA4D levels in patients with paranasal sinus diseases were measured by ELISA. The expression of SEMA4D in blood cells and nasal polyp tissues was assessed by flow cytometry and immunohistochemistry, respectively. Generation of soluble SEMA4D was evaluated in matrix metalloproteinase-treated eosinophils. Endothelial cells were stimulated with recombinant SEMA4D, followed by eosinophil transendothelial migration assays. Allergic chronic rhinosinusitis was induced in mice using Aspergillus protease with ovalbumin. The efficacy of treatment with anti-SEMA4D antibody was evaluated histologically and by nasal lavage fluid analysis.

RESULTS

Serum soluble SEMA4D levels were elevated in patients with ECRS and positively correlated with disease severity. Tissue-infiltrated eosinophils in nasal polyps from patients with ECRS stained strongly with anti-SEMA4D antibody. Cell surface expression of SEMA4D on eosinophils from patients with ECRS was reduced, which was due to matrix metalloproteinase-9-mediated cleavage of membrane SEMA4D. Soluble SEMA4D induced eosinophil transendothelial migration. Treatment with anti-SEMA4D antibody ameliorated eosinophilic infiltration in sinus tissues and nasal lavage fluid in the ECRS animal model.

CONCLUSIONS

Eosinophil-derived SEMA4D aggravates ECRS. Levels of serum SEMA4D reflect disease severity, and anti-SEMA4D antibody has therapeutic potential as a treatment for ECRS.

Differential Expression of Extracellular Matrix Components in Nasal Polyp Endotypes

Background

Chronic rhinosinusitis is a difficult-to-treat disease that is often characterized by recurrent nasal polyp (NP) growth following surgical removal. The disease has been separated into distinct phenotypes based on cellular infiltrate or underlying physiological mechanisms. NPs are composed in part of an inflammatory cellular infiltrate, blood vessels, and a large amount of extracellular matrix (ECM). Despite the recognition of prominent ECM deposition, few studies have examined the components in detail and how they might differ with disease state.

Objective

The purpose of this study was to quantitate the expression of ECM components in NPs.

Methods

NPs were stained with pico-sirius red to determine total collagen content, and immunofluorescence was used to detect collagen I, collagen III, collagen IV, fibronectin, and laminin. Expression of each was quantitated and analyzed in relation to rhinosinusitis phenotype and separately as a function of polyp eosinophil number.

Results

When analyzed by phenotype, collagen I, collagen III, and fibronectin were expressed at the highest levels in noneosinophilic sinus disease. Collagen IV was not different among any groups, and its location was found predominately around vessels. When analyzed as a function of polyp eosinophil number, total collagen and collagen III showed a significant inverse correlation.

Conclusions

NP ECM composition differs with disease state with higher expression in cases where eosinophil levels are low. This suggests that in eosinophilic polyps there is a loss of matrix deposition either through break down or a failure to produce the essential components. Understanding these differences may identify new therapeutic targets.

Transcription factors gene expression in chronic rhinosinusitis with and without nasal polyps

Background Chronic rhinosinusitis (CRS) current therapeutic approaches still fail in some patients with severe persistent symptoms and recurrences after surgery. We aimed to evaluate the master transcription factors gene expression levels of T cell subtypes in chronic rhinosinusitis with nasal polyps (CRSwNP) and chronic rhinosinusitis without nasal polyps (CRSsNP) that could represent new, up-stream targets for topical DNAzyme treatment. Patients and methods Twenty-two newly diagnosed CRS patients (14 CRSwNP and 8 CRSsNP) were prospectively biopsied and examined histopathologically. Gene expression levels of T-box transcription factor (T-bet, TBX21), GATA binding protein 3 (GATA3), Retinoic acid-related orphan receptor C (RORC) and Forkhead box P3 (FOXP3) were analyzed by real-time quantitative polymerase chain reaction (RT-qPCR). Results Eosinophilic CRSwNP was characterized by higher level of GATA3 gene expression compared to noneosinophilic CRSwNP, whereas there was no difference in T-bet, RORC and FOXP3 between eosinophilic and noneosinophilic CRSwNP. In CRSsNP, we found simultaneous upregulation of T-bet, GATA3 and RORC gene expression levels in comparison to CRSwNP; meanwhile, there was no difference in FOXP3 gene expression between CRSwNP and CRSsNP. Conclusions In eosinophilic CRSwNP, we confirmed the type 2 inflammation by elevated GATA3 gene expression level. In CRSsNP, we unexpectedly found simultaneous upregulation of T-bet and GATA3 that is currently unexplained; however, it might originate from activated CD8+ cells, abundant in nasal mucosa of CRSsNP patients. The elevated RORC in CRSsNP could be part of homeostatic nasal immune response that might be better preserved in CRSsNP patients compared to CRSwNP patients. Further data on transcription factors expression rates in CRS phenotypes are needed.

Nasal polyps and future risk of head and neck cancer: A nationwide population-based cohort study

BACKGROUND

Nasal polyps are a common condition with a significant effect on quality of life. The association between nasal polyps and future risk of head and neck cancer is unknown.

OBJECTIVE

We sought to investigate the relative risk of nasal cavity and paranasal sinus (NCPS) and nasopharyngeal cancers in a nationwide, population-based, longitudinal retrospective cohort of patients with nasal polyps and matched comparators.

METHODS

The 2005-2017 National Health Insurance claims and National Health Screening program databases were used to construct a cohort of patients with nasal polyps and matched comparators in Korea. The relative risk of NCPS and nasopharyngeal cancer in patients with nasal polyps was examined.

RESULTS

The study consisted of 453,892 patients with nasal polyps and 4,583,938 matched comparators. The mean duration of follow-up was 6.2 years (range, 2-13 years). The incidence rate ratios of patients with nasal polyps compared with the comparators was 7.00 (95% CI, 5.28-9.25) for NCPS cancer and 1.78 (95% CI, 1.28-2.42) for nasopharyngeal cancer. Increased risks of these cancers were only evident in older subjects (age ≥50 years). There were trends toward weaker associations of nasal polyps with these cancers in younger subjects with comorbid asthma or allergic rhinitis (<50 years).

CONCLUSION

Although the absolute cancer incidence is very low, the relative risk of NCPS or nasopharyngeal cancers was significantly greater in older patients with nasal polyps. Given the regional and pathologic heterogeneity of nasal polyps, further studies are needed to explore the underlying mechanisms and validate the relationships.