Interleukin-17A promotes MUC5AC expression and goblet cell hyperplasia in nasal polyps via the Act1-mediated pathway

BACKGROUND

Recent studies demonstrated that nasal polyps (NP) patients in China and other Asian regions possessed distinct Th17-dominant inflammation and enhanced tissue remodeling. However, the mechanism underlying these observations is not fully understood. This study sought to evaluate the association of interleukin (IL)-17A with MUC5AC expression and goblet cell hyperplasia in Chinese NP patients and to characterize the signaling pathway underlying IL-17A-induced MUC5AC expression in vitro.

METHOD

We enrolled 25 NP patients and 22 normal controls and examined the expression of IL-17A, MUC5AC and act1 in polyp tissues by immunohistochemical (IHC) staining, quantitative polymerase chain reaction (qPCR) and western blot. Moreover, by using an in vitro culture system of polyp epithelial cells (PECs), IL-17A-induced gene expression was screened in cultured PECs by DNA microarray. The expression of IL-17RA, IL-17RC, act1 and MUC5AC and the activation of the MAPK pathway (ERK, p38 and JNK), were further examined in cultured PECs and NCI-H292 cells by qPCR and western blotting, respectively.

RESULTS

We found that increased IL-17A production was significantly correlated with MUC5AC and act1 expression and goblet cell hyperplasia in polyp tissues (p<0.05). IL-17A significantly stimulated the expression of IL-17RA, IL-17RC, act1 and MUC5AC, and the activation of the MAPK pathway in cultured PECs and NCI-H292 cells (p<0.05). In addition, IL-17RA, IL-17RC and act1 siRNA significantly blocked IL-17A-induced MUC5AC production in vitro (p<0.05).

CONCLUSION

Our results suggest that IL-17A plays a crucial role in stimulating the production of MUC5AC and goblet cell hyperplasia through the act1-mediated signaling pathway and may suggest a promising strategy for the management of Th17-dominant NP patients.

Evaluation of patients with nasal polyps about the possible association of desmosomal junctions, RORA and PDE4D gene

OBJECTIVES

Nasal polyposis is chronic inflammatory disease of the nasal mucosa of the nose and sinuses, often associated with chronic non-allergic rhinitis, aspirin intolerance and non-allergic asthma. The etiology of nasal polyposis is unknown. Multiple factors contribute to the development of nasal polyps including genetic predisposition.

PATIENTS AND METHODS

This study was conducted on patients applied due to nasal polyps. Blood samples were collected peripheral vein and stored at 4°C until analysis for DNA extraction. Genomic DNA was extracted from peripheral blood by a standard method, samples were studied in real time PCR. All patients were evaluated about the possible association of DSG1 (rs7236477-G, 96 rxn), DSG3 (rs1941184-C, 96 rxn), PDE4D (rs1588265) and RORA (rs11071559) gene.

RESULTS

32 patients (17 male, 15 female) with nasal polyposis were included to the study. The mean age was 34.9 ± 17.7 years, ranging between 18 and 55 years. Control group was consisted with 50 healthy volunteers without a history of nasal polyp. DSG1, DSG3 and RORA values of the study group were not statistically different from control group (p > 0.05). PDE4D values of the study group were significantly different from control group (p < 0.05).

CONCLUSIONS

Multiple factors contribute to the pathogenesis of nasal polyps including genetic predisposition. The PDE4D family has gained interest in the complex pathogenesis of nasal polyposis. This is likely linked to the mucosal inflammatory response.

Multiplex analyses of cytokine and chemokine release from the cultured fibroblast of nasal polyps: the effect of IL-17A

CONCLUSION

Our results demonstrate for the first time a potentially enhanced basal secretion of monocyte chemoattractant protein-1 (MCP-1) and interleukin (IL)-17A-stimulated secretion of IL-6 from nasal polyp fibroblasts, enhanced basal secretion of IL-6 from eosinophilic nasal polyp fibroblasts, and a remarkable up-regulation of IL-9 and granulocyte colony-stimulating factor (G-CSF) from nasal fibroblasts by IL-17A stimulation.

OBJECTIVES

The fibroblast, one of the main cell types making up nasal polyps, is thought to be a target cell of various cytokines.

METHODS

Subcultured fibroblasts were established from human polyp biopsy tissues. Simultaneous quantification of 27 kinds of cytokines and chemokines in culture supernatants in unstimulated and IL-17A-stimulated conditions was performed with a human multiplex cytokine assay system.

RESULTS

The IL-17A receptor was expressed at similar levels in all three groups. In the eosinophilic group, basal secretion levels of IL-6 were significantly higher than those in the control and non-eosinophilic groups. Basal secretion of MCP-1 in both the non-eosinophilic and eosinophilic groups was also higher than that of the control group. Both IL-9 and G-CSF secretion were remarkably enhanced by IL-17A stimulation in all three groups. The receptor-mediated response by IL-17A significantly up-regulated IL-6 release alone in the non-eosinophilic and eosinophilic groups as compared with the control group.

Clinical survey and analysis of Chinese patients with family history of nasal polyposis

CONCLUSION

Nasal polyposis (NP) is frequently found to run in families. Earlier onset of the condition strongly suggested the genetic basis for the development of NP and implied that it might be a genetic disease involving multiple genes.

OBJECTIVE

The etiology and pathogenesis of NP remain largely unknown, although it is assumed to be associated with allergic reaction and infection. The reported familial cases suggested hereditary factors existing in NP. The purpose of this study was to determine whether a hereditary factor could be implicated in NP.

METHODS

A total of 418 NP patients admitted to our department were questioned concerning the existence of familial history (parents, siblings or children) and other accompanying diseases.

RESULTS

In all, 253 cases were successfully followed up. Among these, 44 cases (17.4%) were confirmed to have a familial history of NP, most (59.1%) of which had two immediate family members with a positive family history, with the distribution significantly greater among first-degree and second-degree relatives. Patients with familial NP reported an earlier onset (mean age = 27.7 years) than the sporadic group (mean age = 32.7 years, t = 2.133, p < 0.05). No statistical significance was found when both groups were associated with fungal and allergic diseases.

Significance of the IL-6 pathway in nasal polyposis in Chinese patients

BACKGROUND

The interleukin-6 (IL-6) pathway is known to be important in Th17 cell differentiation and in the pathology of many inflammatory disorders. However, the significance of the IL-6 pathway in nasal polyposis (NP) in Chinese patients remains unclear.

OBJECTIVE

The aim of this study was to evaluate the functions of the IL-6 pathway in NP in Chinese patients.

METHODS

The levels of IL-6 pathway components, including IL-6, soluble IL-6 receptor (sIL-6R), phosphoSTAT3 (pSTAT3), and suppressor of cytokine signalling 3 (SOCS3), were assessed. The Th17 milieu was examined by measuring the levels of retinoid acid-related orphan receptor C (RORc) and IL-17A.

RESULTS

Levels of IL-6 pathway components, RORc, and IL-17A were significantly higher in both NP groups than in the control(p<0.05). Furthermore, significantly higher levels of pSTAT3, RORc, and IL-17A, and significantly lower levels of SOCS3 were found in the atopic group than in the non-atopic group(P<0.05). IL-6 and sIL-6R levels were not significantly different between the 2 NP groups(P>0.05). pSTAT3 exhibited significantly positive correlations with RORc and IL-17A(P<0.01).

CONCLUSIONS

The expression levels of the IL-6 pathway components were significantly higher in NP patients. Moreover, p-STAT3 levels were much higher in the atopic group, and were associated with a more severe Th17 response. These results suggest that the IL-6 pathway may play a crucial role in the pathology of NP in Chinese patients, and atopy may contribute to NP by affecting the IL-6 pathway.

Microarray analysis of NF-κB-dependent genes in chronic rhinosinusitis with nasal polyps

BACKGROUND

The inflammatory process underlying nasal polyposis is induced and perpetuated by the enhanced activity of several agents including transcription factors. It has recently been demonstrated that one of them, named nuclear factor-kappa B (NF-κB), is implicated in the regulation of multiple pro-inflammatory genes.

OBJECTIVES

The aim of the study was to identify using microarray technology which NF-κB-dependent genes are activated in nasal polyp (NP) samples compared to the control mucosa.

MATERIAL AND METHODS

The transcriptional activity of genes was analyzed using an oligonucleotide microarray on 15 NPs and 8 cases of normal nasal mucosa.

RESULTS

Gene expression patterns obtained in NPs were significantly different from those in normal mucosa. NPs and control cases clustered separately, each of them with large homogeneity in gene expression. Among 582 human NF-κB-dependent genes 25 showed a significantly higher expression in NPs compared to the control. The largest increase focused on gene encoding TFF3 (a 5-fold higher expression) followed by NOS2A (5x), SERPINA1 (4x), UCP2 (4x), OXTR (4x) and IL8 (3x) (p<0.05). In healthy mucosa 19 genes presented increased transcription activity compared to NPs. The most significantly enhanced levels were shown LTF gene (20 fold) followed by KRT6B (7x), LYZ (7x), SD11B2 (5x) and MMP3 (4x) (p<0.05).

CONCLUSIONS

DNA microarray technology highlights the involvement of many unsuspected pathologic pathways which could be involved in NP growth. The identification of novel disease-related genes may help to understand the biology of NPs and elaborate new targeted therapy.

Differential expression of Toll-like receptor pathway genes in chronic rhinosinusitis with or without nasal polyps

CONCLUSIONS

Our results indicate that chronic rhinosinusitis without nasal polyps (CRSsNP) is characterized by the down-regulation of a Toll-like receptor (TLR)-mediated signaling pathway and such a deficiency within the innate immune system may contribute to the inflammatory process of CRSsNP. In contrast, the inflammatory process found in CRS with nasal polyps (CRSwNP) is characterized by an excessively activated TLR-mediated signaling pathway, which may contribute to the formation of nasal polyps. This study suggests that the pathophysiologic mechanism of CRSsNP and CRSwNP is different.

OBJECTIVE

The nasal mucosa expresses a variety of TLRs that serve in recognizing microorganisms. We investigated the gene expression of a TLR-mediated signaling pathway within two distinctive patient subgroups: CRSwNP and CRSsNP.

METHODS

Nasal mucosal tissue was obtained from 78 subjects with CRS and 23 control subjects. qRT-PCR and immunohistochemistry were used to investigate tissues for the expression of TLR2, TLR4, TLR7, their downstream signaling components, MyD88 and TRIF, and associated cytokines, interferon (IFN)-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-4, and IL-10.

RESULTS

TLR2, TLR4, TLR7, and IL-4 were significantly increased in CRSwNP patients when compared with either CRSsNP patients or control subjects, whereas TLR4 and TLR7, and downstream MyD88 were significantly decreased in CRSsNP patients versus patients from CRSwNP and control subjects.

A global analysis of tandem 3'UTRs in eosinophilic chronic rhinosinusitis with nasal polyps

Background

Alternative polyadenylation (APA) is emerging as a widespread mechanism of gene regulation. The usage of APA sites allows a single gene to encode multiple mRNA transcripts with different 3′-untranslated region (3′UTR) lengths. Many disease processes reflect the importance of the regulation of APA site switching. The objective of this study was to explore the profiling of tandem APA sites in nasal polyps compared with nasal uncinate process mucosa.

Methods

Sequencing of APA sites (SAPAS) based on second-generation sequencing technology was undertaken to investigate the use of tandem APA sites and identify gene expression patterns in samples from the nasal polyps and nasal uncinate process mucosa of two patients with chronic rhinosinusitis with nasal polyps. The findings of the SAPAS analysis were validated via quantitative reverse-transcription polymerase chain reaction (qRT-PCR).

Results

First, the results showed a switching of 3′UTR lengths in nasal polyps compared with nasal uncinate process mucosa. From the two patients, 105 genes that were detected in both patients in the nasal polyps were switched to distal poly(A) sites, and 90 such genes were switched to proximal poly(A) sites. Several Gene Ontology terms were enriched in the list of genes with switched APA sites, including transcription regulation, cell cycle, apoptosis, and metabolism. Second, we detected genes that showed differential expression with at least a 3-fold difference between nasal polyp tissue and nasal uncinate process mucosa. Between the two sample types, 627 genes exhibited differential expression. The qRT-PCR results confirmed our SAPAS results.

Conclusion

APA site-switching events of 3′UTRs are prevalent in nasal polyp tissue, and the regulation of gene expression mediated by APA may play an important role in the formation and persistence of nasal polyps. Our results may provide new insights into the possible pathophysiologic processes involved in nasal polyps.

Reciprocal roles of STAT3 and STAT5 in nasal polyposis

PURPOSE

Nasal polyposis (NP) is a chronic inflammatory disease that is characterized by increased populations of Th17 cells and impairment of Treg cells function in Chinese patients. Recent studies have shown that signal transducer and activator of transcription 3 (STAT3) and STAT5 are indispensable in the development and maintenance of Th17 and Treg cells. We investigated the roles of STAT3 and STAT5 in the imbalance of Th17 and Treg cells in NP.

MATERIALS AND METHODS

The levels of IL-6, IL-2, pSTAT3, pSTAT5, SOCS3, RORc, Foxp3, IL-17A, and TGF-β1 were measured in patients with atopic NP, patients with nonatopic NP, and controls. We also evaluated the local distribution of Th17 and Treg cells by double immunofluorescence staining and the correlations between activated STAT3/STAT5 and Th17/Treg cell development were assessed.

RESULTS

Increased levels of IL-6, pSTAT3, SCOS3, RORc, IL-17A, and CD4(+) RORc(+) cells, and decreased levels of IL-2, pSTAT5, Foxp3, TGF-β1, and CD4(+) Foxp3(+) cells were detected in both NP groups compared to controls (P < .05). The differences in all expression levels (except for IL-6) were significant between atopic and nonatopic patients (P < .05). There was a positive correlation between pSTAT3/pSTAT5 levels and Th17/Treg development and a negative correlation between SOCS3 and pSTAT3 in NP (P < 0.01).

CONCLUSIONS

The results suggest that STAT3 and STAT5 may function through the IL-6 and IL-2 pathways to play a role in the imbalance of Th17/Treg in NP. An even more exaggerated imbalance of Th17/Treg caused by atopy may be correlated to the improper ratio of activated STAT3/STAT5.

Polymorphisms in RYBP and AOAH genes are associated with chronic rhinosinusitis in a Chinese population: a replication study

Background

The development of CRS is believed to be the result of combined interactions between the genetic background of the affected subject and environmental factors.

Objectives

To replicate and extend our recent findings from genetic association studies in chronic rhinosinusitis (CRS) performed in a Canadian Caucasian population in a Chinese population.

Methods

In a case-control replication study, DNA samples were obtained from CRS with (n = 306; CRSwNP) and without (n = 332; CRSsNP) nasal polyps, and controls (n = 315) in a Chinese population. A total of forty-nine single nucleotide polymorphisms (SNPs) selected from previous identified SNPs associated with CRS in Canadian population, and SNPs from the CHB HapMap dataset were individually genotyped.

Results

We identified two SNPs respectively in RYBP (rs4532099, p = 2.15E–06, OR = 2.59) and AOAH (rs4504543, p = 0.0001152, OR = 0.58) significantly associated with whole CRS cohort. Subgroup analysis for the presence of nasal polyps (CRSwNP and CRSsNP) displayed significant association in CRSwNP cohorts regarding to one SNP in RYBP (P = 3.24^E–006, OR = 2.76). Evidence of association in the CRSsNP groups in terms of 2 SNPs (AOAH_rs4504543 and RYBP_rs4532099) was detected as well. Stratifying analysis by gender demonstrated that none of the selected SNPs were associated with CRSwNP as well as CRSsNP. Meanwhile 3 SNPs (IL1A_rs17561, P = 0.005778; IL1A_rs1800587, P = 0.009561; IRAK4_rs4251513, P = 0.03837) were associated with serum total IgE level.

Conclusions

These genes are biologically plausible, with roles in regulation of transcription (RYBP) and inflammatory response (AOAH). The present data suggests the potential common genetic basis in the development of CRS in Chinese and Caucasian population.

Retrospective analysis of chronic rhinosinusitis in patients with cystic fibrosis

INTRODUCTION

Chronic rhinosinusitis is very common in patients with cystic fibrosis. This can be explained by the unified airway concept, where the same pathophysiological phenomenon that affects the lungs, affects the paranasal sinuses. The management of these cases is difficult.

OBJECTIVE

To describe the teamwork of otolaryngologists and bronchopulmonary specialists in patients with cystic fibrosis.

METHOD

We performed a descriptive, retrospective study over the last 17 years, which included 14 patients with chronic rhinosinusitis and cystic fibrosis attended at a private hospital.

RESULTS

Of the patients, 64% were male and the median age was 23 years. The most frequent mutations found were ΔF508, M470 and R553. All of the patients with ΔF508 mutation had nasal polyps. 100% of the patients had clinical findings of chronic rhinosinusitis. All the patients had had endoscopic nasal surgery. The median number of endoscopic surgeries was 2.

CONCLUSIONS

Given the high prevalence of chronic rhinosinusitis in patients with cystic fibrosis, everyone should have a computed tomography scan of the paranasal sinuses during the initial assessment, considering that sinus germs are the ones that colonise the lower airway. The otolaryngologist should be part of the cystic fibrosis team. Before receiving a lung transplant or in cases of chronic headache, endoscopic surgery should be performed in patients in whom medical treatment fails to clear the sinuses because this infection is the one that colonises the lower airway.

Primary small cell carcinoma of the maxillary sinus: a case report with immunohistochemical and molecular genetic study involving KIT and PDGFRA

Primary small cell carcinoma of the nose and paranasal sinuses is very rare; only a few reports are present in the English literature. The author herein reports a very rare case of primary small cell carcinoma of the maxillary sinus with an emphasis on immunohistochemistry and on KIT and PDGFRA. A 64-year-old man was admitted to our hospital because of left nasal obstruction. Endoscopy revealed three nasal polyps, and imaging modalities revealed an infiltrative tumor (45 x 45 mm) in the left maxillary sinus with invasion into nasal cavity. Multiple biopsies are taken from the nasal lesions. Histologically, the tumor consists of proliferation of malignant small epithelioid cells with hyperchromatic nuclei, fine chromatin, scant cytoplasm, molded nuclei, and absent nucleoli. Immunohistochemically, the malignant cells were positive for cytokeratin (CK) 18, synaptophysin, CD56, p53, Ki-67 (labeling=95%), bcl-2, KIT, and PDGFRA. However, they were negative for pancytokeratins, high molecular weight CK, CK5/6, CK7, CK 14, CK 19, CK20, vimentin, neuron-specific enolase, chromogranin, CD15, CD45, S100 protein, CEA, CA19-9, glial fibrillary acidic protein, neurofilaments, neuroblastoma, CD99, surfactant apoprotein A, melanosome, and TTF-1. The pathologic diagnosis was small cell carcinoma. A molecular genetic analysis using PCR-direct sequencing was performed using paraffin sections, and it showed no mutations of KIT (exons 9, 11, 13, and 17) and PDGFRA (exons 12 and 18) genes. Imaging modalities including CT, MRI and PET did not reveal any tumors, including the lung, other than the maxillary sinus tumor. The present case is the first of small cell carcinoma of the maxillary sinus with a comprehensive immunohistochemical examination and a gene analysis of KIT and PDGFRA.

[Association of susceptibility to chronic rhinosinusitis with genetic polymorphisms of IL-4 and IL-10]

OBJECTIVE

To investigate the relationship between the promoter polymorphism of IL-4 and IL-6 and chronic rhinosinusitis (CRS).

METHODS

One hundred and twenty-three patients with CRS and 239 healthy controls in Shanghai region were chosen in this study. The genotype of IL-4 gene -33T>C and -590C>T were determined using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method and the genotype of IL-10 gene -1082A>G was determined using amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) method. Statistical calculations were performed using SAS 8.2 software.

RESULTS

Significant differences were found in genotype distribution of -33T>C and -590C>T between the CRS group and the control group (χ2=6.6013, P=0.0102, χ2=6.6013, P=0.0304), and -33T>C remained significant following application of the Bonferroni correction (P<0.025). The relative risks of CRS with -33T>C and -590C>T were 1.818(P=0.0236, 95%CI 1.084-3.050) and 1.838 (P=0.0147, 95%CI 1.127-2.997). There was linkage disequilibrium (LD) between the -33T>C and -590C>T. The coefficient of linkage disequilibrium (D') was 0.77 and the related coefficient (r2) was 0.54. The -33T/-590T haplotype was associated with CRS and the relative risk was 1.653 (P=0.0130, 95%CI 1.107-2.469). There were only two genotypes of IL-10 gene-1082A>G and the frequencies of the AA and AG genotypes were not different between the CRS and control groups.

CONCLUSION

The promoter polymorphism of IL-4 -33T>C and -590C>T were associated with the susceptibility of CRS and the -33T/-590T haplotype was a risk factor for CRS, but there were no association between the -1082A>G and CRS.

Genetic association study in nasal polyposis

BACKGROUND AND OBJECTIVES

Nasal polyposis (NP) is a chronic inflammatory disease of the upper airways with a variable clinical course and unknown pathogenesis that often coexists with other conditions. Considering the possibility of genetic predisposition, we decided to analyze whether polymorphisms in LTC4S, CYSLTR1, PTGDR, and NOS2A were associated with NP.

METHODS

The study population comprised 486 Caucasian individuals. Polyposis and aspirin intolerance were diagnosed following the recommendations of the European Position Paper on Rhinosinusitis and Nasal Polyps. Genotypes were determined using polymerase chain reaction amplification and direct sequencing.

RESULTS

The -444A > C LTC4S polymorphism was significantly associated with NP and atopy (P = .033) and with NP and atopic asthma, (P =.012). In addition, a significant association was found when the (CCTTT) repetition of the NOS2A gene was present more than 14 times in patients with NP and asthma (P = .034), in patients with polyposis and intolerance to nonsteroidal anti-inflammatory drugs (P = .009), and in patients with the aspirin triad (P = .005). The PTGDR diplotype CCCT/CCCC (-613CC, -549CC, -441CC and -197TC) was more frequent in patients with NP (P = .043), NP with asthma (P = .013), and the aspirin triad (P = .041).

CONCLUSIONS

NP was associated with specific polymorphisms only when it occurred with related phenotypes. Our results suggest that this genetic background plays a more relevant role in the development of the associated clinical features of nasal polyposis than in simple polyposis.

Association between the functional polymorphism C-159T in the CD14 promoter gene and nasal polyposis: potential role in asthma

BACKGROUND

Nasal polyposis (NP) is a chronic inflammatory disease that is frequently associated with allergy and asthma. Corticosteroid therapy and surgical removal of polyps are the 2 most common treatment strategies for NP. Various allergic and inflammatory mediators are thought to play a major role in the pathophysiology of this disorder. The CD14 gene is located on chromosome 5q31-32, which is considered a critical region for several allergic and atopic diseases, including asthma. Consequently, variations in CD14 could have functional effects on the etiology and severity of allergy and asthma. The aim of this study was to investigate the association between the polymorphism C-159T in the CD14 gene of patients with NP and controls.

METHODS

The study population comprised 106 patients with NP diagnosed based on computed tomography scan of the paranasal sinus, endoscopy, and histological examination. Findings were compared with those from 87 controls. The frequency of C-159T was determined using polymerase chain reaction-restriction fragment length polymorphism analysis. DNA was extracted using the salting out technique.

RESULTS

A significant association was observed between C-159T and NP (P = .04). Patients with the CC genotype at position -159 of the CD14 promoter region had an increased risk of asthma (OR, 3.83, 95% CI, 0.99-13.91; P < .02). However, we did not find an association between the distribution of C-159T and serum immunoglobulin E level.

CONCLUSIONS

A genetic variation in the CD14 promoter might play a role in the pathogenesis of NP and in the incidence of asthma.

Association of the -33C/G OSF-2 and the 140A/G LF gene polymorphisms with the risk of chronic rhinosinusitis with nasal polyps in a Polish population

Nasal polyps are strongly associated with a risk of chronic rhinosinusitis development as well as other obstruction including asthma and allergy. The following study tested the association of the 140A/G polymorphism of lactoferine (LF) encoding gene and the -33C/G polymorphism of osteoblast-specific factor-2 (OSF-2) encoding gene with a risk of chronic rhinosinusitis with nasal polyps in a Polish population. One hundred ninety five patients of chronic rhinosinusitis with nasal polyps as well as 200 sex, age and ethnicity matched control subjects without chronic sinusitis and nasal polyps were enrolled in this study. Among the group of patients 63 subjects were diagnosed with allergy and 65 subjects with asthma, respectively. DNA was isolated from peripheral blood lymphocytes of patients as well as controls and gene polymorphisms were analyzed by restriction fragments length polymorphism polymerase chain reaction (RFLP-PCR). We reported that the 140A/G LF (OR 4.78; 95% CI 3.07-7.24), the -33C/G OSF-2 OR 3.48; 95% CI 2.19-5.52) and the -33G/G OSF-2 (OR 16.45; 95% CI 6.71-40.30) genotypes were associated with an increased risk of chronic rhinosinusitis with nasal polyps among analyzed group of patients. Moreover, the group of patients without allergy or asthma indicated the association of the -33C/G (OR 3.72; 95% CI 2.24-6.19 and OR 15.11; 95% CI 5.91-38.6) and -33G/G (OR 3.73; 95% CI 2.24-6.19 and OR 14.07; 95% CI 5.47-36.16) genotypes of the OSF-2 as wells as 140A/G (OR 3.89; 95% CI 2.40-6.31 and OR 3.62; 95% CI 2.45-5.34) genotype of OSF-2 with an increased risk of chronic rhinosinusitis with nasal polyps. Finally, it was also found that the selected group of patients with allergy or asthma indicated a very strong association of the -33C/G (OR 2.40; 95% CI 1.23-4.69 and OR 2.40; 95% CI 1.23-4.69, respectively) and -33G/G (OR 16.01; 95% CI 5.77-44.41 and OR 17.90; 95% CI 6.53-49.05, respectively) genotypes of the OSF-2 as wells as 140A/G (OR 3.22; 95% CI 1.74-6.11 and OR 3.25; 95% CI 1.75-6.04, respectively) genotypes with an increased risk of chronic rhinosinusitis with nasal polyps. Thus, our results suggest that LF and OSF-2 gene polymorphisms may have deep impact on the risk of rhinosinusitis nasal polyps' formation which may also depend on asthma or allergy. Our results showed that the 140A/G polymorphism of LF gene and the -33C/G polymorphism of the OSF-2 gene may be associated with the risk of chronic rhinosinusitis with nasal polyps in a Polish population.

Retinoic acid-inducible gene 1-like receptors in the upper respiratory tract

BACKGROUND

Retinoic acid-inducible gene 1-like receptors (RLRs) are a novel family of pattern recognition receptors that include retinoic acid-inducible gene 1 (RIG-1), melanoma differentiation-associated gene 5 (MDA-5), and laboratory of genomics and physiology 2 (LGP-2). The knowledge of RLRs and their function in the human airway is limited. This study explores the role of RLRs in the upper respiratory tract.

METHODS

Tonsils, adenoids, nasal polyps, and biopsy specimens from the nasal mucosa were examined for the occurrence of the RIG-1, MDA-5, and LGP-2 using real-time reverse-transcription polymerase chain reaction and immunohistochemistry. The nasopharyngeal epithelial cell line FaDu was cultured with the RIG-1/MDA-5 ligand poly(I:C)/LyoVec (Invivogen, San Diego, CA) and analyzed for cytokine release using ELISA.

RESULTS

RIG-1, MDA-5, and LGP-2 mRNA were found in all tissues tested. The airway epithelium appeared to be their most prominent location. The RIG-1 and MDA-5 mRNA levels were higher in nasal polyps than in normal nasal mucosa, a state that seemed to be reversed by local steroid treatment. Culture of FaDu with poly(I:C)/LyoVec resulted in IL-6 and IL-8 release. No alteration in RLR expression in tonsils was seen on infection.

CONCLUSION

This study shows the presence and functional activity of RLRs in the human upper airways. It also suggests a role for RLRs in nasal polyposis.

Activation-induced cytidine deaminase (AID)-associated multigene signature to assess impact of AID in etiology of diseases with inflammatory component

Activation-induced cytidine deaminase (AID) is expressed in B cells within germinal centers and is critically involved in class switch recombination and somatic hypermutation of immunoglobulin loci. Functionally active AID can additionally be detected within ectopic follicular structures developed at sites of chronic inflammation. Furthermore, AID may target non-Ig genes in B- and non-B-cell background. Therefore, AID-associated effects are of increasing interest in disease areas such as allergy, inflammation, autoimmunity, and cancer.Pathway- or disease-relevant multigene signatures have attracted substantial attention for therapeutic target proposal, diagnostic tools, and monitoring of therapy response. To delineate the impact of AID in etiology of multifactorial diseases, we designed the AID-associated 25-gene signature. Chronic rhinosinusitis with nasal polyps was used as an inflammation-driven airway disease model; high levels of IgE have been previously shown to be present within polyp tissue. Expression levels of 16 genes were found to be modulated in polyps including AID, IgG and IgE mature transcripts which reflect AID activity; clustering algorithm revealed an AID-specific gene signature for the disease state with nasal polyp. Complementary, AID-positive ectopic lymphoid structures were detected within polyp tissues by in situ immunostaining. Our data demonstrate the class switch recombination and somatic hypermutation events likely taking place locally in the airways and in addition to the previously highlighted markers and/or targets as IL5 and IgE suggest novel candidate genes to be considered for treatment of nasal polyposis including among others IL13 and CD23. Thus, the algorithm presented herein including the multigene signature approach, analysis of co-regularities and creation of AID-associated functional network gives an integrated view of biological processes and might be further applied to assess role of altered AID expression in etiology of other diseases, in particular, aberrant immunity and cancer.

Topographic gene expression in the sinonasal cavity of patients with chronic sinusitis with polyps

OBJECTIVE

To determine whether variations in gene expression exist at multiple subsites along the sinonasal tract in patients with chronic sinusitis with polyps and in healthy controls.

STUDY DESIGN

Prospective, controlled study.

SETTING

Academic medical center.

SUBJECTS AND METHODS

Tissue expression levels of 5 genes, previously found to be characteristic of ethmoid polyps, were measured using real-time quantitative polymerase chain reaction in 100 sinonasal tissue samples. Specimens harvested from 5 regions--the ethmoid sinus, septum, inferior turbinate, middle turbinate, and lateral nasal wall--in 10 patients with chronic sinusitis and ethmoid polyps were compared to tissue from similar regions in 10 control patients without sinusitis. Western blot analysis was performed to validate differential gene expression at the protein level.

RESULTS

Gene expression levels of ethmoid polyps differed significantly from those of healthy ethmoid mucosa, as well as tissue from 4 surrounding anatomical sites in both patients with chronic sinusitis and controls. Alterations specific to the polyp tissue included downregulated genes, prolactin-induced protein (fold change 377.2 ± 169.0, P < .0001), and zinc α2-glycoprotein (fold change 72.1 ± 26.5, P < .0001), as well as upregulated genes, met proto-oncogene (fold change 2.5 ± 0.7, P = .029), and periostin (fold change 7.5 ± 3.4, P = .003). No significant differences in gene expression was found for neurabin 2 (fold change 1.0, P = .99).

CONCLUSION

The transcriptional pattern of ethmoid polyps appears to be unique compared with other subsites in the sinonasal cavity of patients with chronic sinusitis. Care must be taken when collecting specimens for molecular studies of the sinonasal tract to differentiate polyp from nonpolyp tissue in chronic sinusitis.

Genome-wide methylation profile of nasal polyps: relation to aspirin hypersensitivity in asthmatics

BACKGROUND

In addition to the dysregulation of arachidonic acid metabolism in aspirin-intolerant asthma (AIA), aspirin acetylsalicylic acid (ASA) exerts effects on inflammation and immunity; however, many of these effects are unknown.

OBJECTIVE

The aim of the study was to evaluate the methylation status of whole genome in blood and polyp tissues with and without aspirin hypersensitivity.

METHODS

Genome-wide DNA methylation levels in nasal polyps and peripheral blood cells were examined by microarray analysis using five subjects with AIA and four subjects with aspirin-tolerant asthma (ATA).

RESULTS

In the nasal polyps of the patients with AIA, hypermethylation was detected at 332 loci in 296 genes, while hypomethylation was detected at 158 loci in 141 genes. Gene ontologic and pathway enrichment analyses revealed that genes involved in lymphocyte proliferation, cell proliferation, leukocyte activation, cytokine biosynthesis, cytokine secretion, immune responses, inflammation, and immunoglobulin binding were hypomethylated, while genes involved in ectoderm development, hemostasis, wound healing, calcium ion binding, and oxidoreductase activity were hypermethylated. In the arachidonate pathway, PGDS, ALOX5AP, and LTB4R were hypomethylated, whereas PTGES was hypermethylated.

CONCLUSION

The nasal polyps of patients with AIA have characteristic methylation patterns affecting 337 genes. The genes and pathways identified in this study may be associated with the presence of aspirin hypersensitivity in asthmatics and are therefore attractive targets for future research.

Expression and role of acidic mammalian chitinase and eotaxin-3 in chronic rhinosinusitis with nasal polyps

OBJECTIVE

Acidic mammalian chitinase (AMCase) has been found to play an important role in allergy and asthma. Chronic rhinosinusitis with nasal polyps (CRSwNPs) is chronic inflammation with eosinophilic infiltration, which is similar to asthmatic inflammation. The role of AMCase in CRSwNPs has been less studied. Eotaxin-3 is a potent eosinophil attractant and can induce eosinophil recruitment and activation in the airways of asthmatics. The expression and role of eotaxin-3 messenger ribonucleic acid (mRNA) and its relationship to AMCase in CRSwNPs have not been studied previously.

SUBJECTS AND METHODS

Twenty-three subjects with nasal polyps and nine subjects with nasal septum deviation were included in the study. The polyps and inferior turbinate mucosa were obtained as the tissue samples. Real-time reverse transcriptase-polymerase chain reaction was used to analyze and compare the expression levels of AMCase and eotaxin-3 in nasal polyps and inferior turbinate tissues (ITTs).

RESULTS

AMCase and eotaxin-3 were detected in all nasal polyps and ITTs. The expression ratio of AMCase mRNA was 123.90 ± 30.60 in nasal polyps and 2.38 ± 0.41 in ITTs. The expression ratio of eotaxin-3 mRNA was 43.58 ± 15.15 and 0.84 ± 0.30, respectively. The expression of AMCase and eotaxin-3 mRNA was significantly higher in nasal polyps than in ITTs (p < .01).

CONCLUSIONS

Our results reveal that AMCase and eotaxin-3 may be important mediators in the pathogenesis of nasal polyps. The increased AMCase and eotaxin-3 might lead to nasal polyp formation and growth. Future studies are needed to determine the potential of AMCase and eotaxin-3 as therapeutic targets in CRSwNPs.

Enhanced susceptibility of nasal polyp tissues to avian and human influenza viruses

BACKGROUND

Influenza viruses bind and infect respiratory epithelial cells through sialic acid on cell surface. Differential preference to sialic acid types contributes to host- and tissue-tropism of avian and seasonal influenza viruses. Although the highly pathogenic avian influenza virus H5N1 can infect and cause severe diseases in humans, it is not efficient in infecting human upper respiratory tract. This is because of the scarcity of its receptor, α2,3-linked sialic acid, in human upper airway. Expression of sialic acid can be influenced by various factors including inflammatory process. Allergic rhinitis and nasal polyp are common inflammatory conditions of nasal mucosa and may affect expression of the sialic acid and susceptibility to influenza infection.

METHODOLOGY/PRINCIPAL FINDING

To test this hypothesis, we detected α2,3- and α2,6-linked sialic acid in human nasal polyp and normal nasal mucosal tissues by lectin staining and infected explants of those tissues with avian influenza viruses H5N1 and seasonal influenza viruses. We show here that mucosal surface of nasal polyp expressed higher level of α2,3- and α2,6-linked sialic acid than normal nasal mucosa. Accordingly, both H5N1 avian influenza viruses and seasonal influenza viruses replicated more efficiently in nasal polyp tissues explants.

CONCLUSIONS/SIGNIFICANCE

Our data suggest a role of nasal inflammatory conditions in susceptibility to influenza infection, especially by avian influenza viruses, which is generally inefficient in infecting human upper airway. The increased receptor expression may contribute to increased susceptibility in some individuals. This may contribute to the gradual adaptation of the virus to human population.

Genetic evidence for a role of IL33 in nasal polyposis

BACKGROUND

Little is known about the genetic factors that contribute to nasal polyposis (NP). A genome-wide association study identified 10 single nucleotide polymorphisms (SNPs) associated with eosinophilia. As eosinophils play a key role in the pathogenesis of NP, we assessed if any of these SNPs contribute to genetic susceptibility of NP.

METHODS

We recruited 284 patients with NP in four participating hospitals in Belgium and 427 healthy controls, and genotyped 10 SNPs affecting eosinophilia (rs1420101 in IL1RL1, rs12619285 in IKZF2, rs4431128 in GATA2, rs4143832 in IL5, rs3184504 in SH2B3, rs2416257 in WDR36, rs2269426 in MHC, rs9494145 in MYB, rs748065 in GFRA2, and rs3939286 in IL33) using MALDI-TOF. A two-stage design was used while correcting for multiple testing.

RESULTS

First stage analysis, involving 150 NP patients and 250 controls, identified rs3939286 nearby IL33 as a susceptibility factor for NP. Per at-risk A-allele, rs3939286 increased the risk for NP with an odds ratio (OR) of 1.60 (95% CI = 1.16-2.22; P = 0.0041). Second stage replication analysis in another 123 NP patients and 165 controls confirmed this association (OR = 1.43; CI = 1.00-2.06; P = 0.046). The combined analysis of both stages revealed an OR of 1.53 (CI = 1.21-1.96; P = 0.00041). Given the association of IL33 with NP, we also investigated rs1420101 in IL1RL1, which is the receptor for IL33. Although rs1420101 itself failed to associate with NP, a combined risk assessment of rs3939286 and rs1420101 further increased the risk for NP.

CONCLUSION

We provide unprecedented genetic evidence suggesting a role for the IL33 pathway in the pathogenesis of NP.

[Effects of double-stranded RNA poly(I:C) on matrix metalloproteinase mRNA expression in human nasal polyp epithelial cells]

OBJECTIVE

Chronic rhinosinusitis was often exacerbated by viral infection. A disruption of the mechanisms that regulate the activity of matrix metalloproteinases (MMPs) during viral infection was one possible mechanism responsible for the exacerbation. The purpose of study was to achieve a better understanding of MMP expression in nasal epithelial cells after viral infection.

METHODS

Human nasal epithelial cells were isolated from nasal polyp specimens obtained during endoscopic endonasal surgery in chronic rhinosinusitis patients. The expression of MMP-2, MMP-9, and tissue inhibitor of metalloproteinase (TIMP)-1 mRNA in primary human nasal polyp epithelial cells after double stranded RNA (ds RNA) stimulation were investigated.

RESULTS

Among the genes whose expression was evaluated, only expression of MMP-9 mRNA increased significantly after dsRNA stimulation (22.61 +/- 5.47 fold increase, Z = -2.52, P = 0.012).

CONCLUSIONS

The significant up-regulation of MMP-9 mRNA, which was not modulated by TIMP-1, was an additional source of increased proteolytic activity in virus-infected upper airways that might contribute to the exacerbation of chronic rhinosinusitis with nasal polyps.

Analysis of syndecan-1 and TGF-beta expression in the nasal mucosa and nasal polyps

OBJECTIVE

Increased understanding of cytokines and their associated proteoglycans will contribute to the investigation of the formation of nasal polyps. Recently, some studies have suggested that syndecan-1 ectodomains are shed in response to low respiratory infection, but no studies regarding nasal and paranasal diseases have been reported. Transforming growth factor-beta (TGF-beta) is involved in the regulation of nasal polyps, especially in processes crucial to the initiation, maintenance, and resolution of inflammatory responses. In the nasal mucosa and nasal polyps, we analyzed the expression of syndecan-1, which readily promotes infection, and TGF-beta, which plays a role in syndecan-1 activity.

METHODS

Fifteen patients who underwent turbinectomy for the treatment of nasal obstruction and seventeen patients with nasal polyps who underwent nasal endoscopic sinus surgery were included in this study. The localization of syndecan-1 and TGF-beta in the nasal mucosa and nasal polyps was investigated by immunohistochemistry, and mRNA transcript levels of syndecan-1 and TGF-beta were examined using quantitative real-time PCR.

RESULTS

Immunohistochemical staining revealed that the expression of syndecan-1 in the nasal mucosa and nasal polyps was co-localized with TGF-beta. The mean mRNA expression values for syndecan-1 and TGF-beta were higher in nasal polyps compared to the nasal mucosa.

CONCLUSIONS

This is the first report showing expression of syndecan-1 in the nasal mucosa and nasal polyps. In nasal polyps, syndecan-1 expression may be increased by an unknown mechanism, permitting infection and inducing larger nasal polyps. We hypothesize that the accumulation of TGF-beta, which is involved in the pathophysiological development of nasal polyps, may result in a change in the binding properties of syndecan-1 at inflammatory sites.