Co-expression of the TGF-beta1 and TGF- beta2 isoforms in nasal polyps and in healthy mucosa

BACKGROUND

The formation of nasal polyps is connected with a chronic inflammatory process with the activation of different cytokines. TGF-ss induces fibrosis and acts as a chemoattractant and proliferation factor for fibroblasts. The aim of the study was to evaluate the expression profiles of the genes coding TGF-ss isoforms in nasal polyps with predominately eosinophilic and neutrophilic infiltration and in healthy mucosa and to assess their mutual correlation with the levels of gene transcription.

MATERIAL/METHODS

The study group consisted of 24 patients with nasal polyposis. On the basis of the histopathological evaluation there were 16 eosinophilic and 8 neutrophilic polyps. The control group constituted 9 healthy patients. The expression profiles of the genes coding the TGF-ss isoforms were detected using real-time RT-QPCR.

RESULTS

TGF-beta1 and TGF-beta2 mRNAs were revealed in 10 patients with eosinophilic polyps. TGF-beta1 transcriptional activity was accompanied by TGF-beta2 transcriptional activity in nasal polyps. TGF-beta2 gene expression in tissues without mRNA for TGF-beta1 was silenced. There was positive correlation between the expressions of the TGF-beta1 and TGF-beta2 isoforms in nasal polyps. TGF-beta1 mRNA was present at higher levels in all control samples than in eosinophilic polyps. An increased TGF-beta1 mRNA expression was accompanied by an increased TGF-beta2 mRNA expression in healthy mucosa. TGF-beta3 showed the most intensive transcriptional activity among the TGF-ss isoforms in both nasal polyps and control tissues. There was no correlation between TGF-beta3 and TGF-beta1 nor between TGF-beta3 and TGF-beta2 transcriptional activity in nasal polyps and normal tissue.

Mutations and differential expression of the ras family genes in human nasal polyposis

Although it is well established that ras genes contribute to tumourigenesis either through the accumulation of mutations or by aberrant expression in a wide range of human cancers, little is known regarding their involvement in human nasal polyps (NPs). In the present study, the occurrence of mutations in codons 11 and 12 of the ras family genes was examined by PCR/RFLP and direct sequencing in 23 human NPs and their adjacent turbinates, as well as in turbinates from 13 control subjects. Moreover, the expression pattern of ras mRNA levels was assessed in NP specimens and compared to adjacent and control tissues. K-ras codon 11 and 12 mutations were detected in 17 and 35% of NPs, respectively, and were found in the adjacent inferior turbinate (AIT) (22 and 16%, respectively) and adjacent middle turbinates (AMT) (16 and 26%, respectively). K- and H-ras expression levels were elevated, whereas N-ras mRNA levels were lower in NPs and adjacent turbinates as compared to the control tissues. K-ras mRNA levels were up-regulated in advanced-stage polyps (P=0.037), while N-ras levels were found elevated in small polyps (P=0.046). Statistically significant negative correlations between K- and N-ras expression profiles arose in NPs and AITs (P=0.009 and 0.003, respectively). This, to our knowledge, is the first report on ras mutations and expression analysis in NPs. Our findings suggest a potential key role for activated members of ras family genes in terms of their contribution to the development of NPs as well as to the hypertrophy of adjacent turbinates.

Connectivity can be used to identify key genes in DNA microarray data: a study based on gene expression in nasal polyps before and after treatment with glucocorticoids

CONCLUSIONS

The presented analysis of nasal polyposis using connectivity based on the PubGene literature co-citation network demonstrates that this tool can be used to identify key genes in DNA microarray studies of human polygenic diseases.

OBJECTIVES

DNA microarray studies of complex diseases may reveal differential expression of hundreds of genes. According to network theory and studies of yeast cells, genes that are connected with several other genes appear to have key regulatory roles. This study aimed to examine if this principle can be translated to DNA microarray studies of human disease, using nasal polyposis as a base for the analysis.

MATERIALS AND METHODS

The connectivity of differentially expressed genes from a previously described microarray study of nasal polyposis before and after treatment with glucocorticoids was determined. This was done using the literature co-citation network PubGene.

RESULTS

In all, 166 genes were differentially expressed; 39 of these were previously defined as inflammatory and considered important for nasal polyposis. The connectivity of all differentially expressed genes was analysed using the PubGene literature co-citation network. Seventy-four of the 166 genes were connected to other genes. By contrast, the average number of connected genes among 100 sets of 166 randomly chosen genes was 31.5. A small number of the differentially expressed genes were highly connected, while most genes had few or no connections. This indicated a scale-free network. The most connected gene was interleukin-8, an inflammatory gene of known importance for nasal polyposis. Twenty-eight of the 74 connected genes were inflammatory (38%), compared with 11 of the 92 unconnected genes (12%), p < 0.0001. Since most evidence suggests that nasal polyps are inflammatory in their nature, this supports the hypothesis that connected genes have more disease relevance than unconnected genes.

Proinflammatory cytokine single nucleotide polymorphisms in nasal polyposis

OBJECTIVE

To investigate the association between nasal polyposis (NP) and single nucleotide polymorphisms of the proinflammatory cytokines IL (interleukin) 1alpha (the IL1A gene), IL-1beta (the IL1B gene), and tumor necrosis factor alpha (the TNFA gene).

DESIGN

Prospective case-control trial.

SETTING

Tertiary referral center.

PATIENTS

Eighty-two patients with NP and 106 healthy volunteers without sinonasal disease.

MAIN OUTCOME MEASURES

Genotypes of IL1A (4845G, 4845T), IL1B (-511C, -511T) and TNFA (-238G, -238A and -308G, -308A) were identified by restriction fragment length polymorphism analyses after polymerase chain reaction.

RESULTS

The 4845 GT and 4845 TT genotypes of the IL1A gene were associated with NP (P<.05). The frequency of the -511 CC genotype of the IL1B gene was significantly higher in patients with NP than in controls (P=.01). The frequency of the -511 CT genotype of IL1B was significantly higher (P=.01) in the controls than in the patients with NP. The -238 AA genotype of the TNFA gene was higher in the patients with NP than in the controls (P=.05). There was a significantly high risk of susceptibility to NP in patients with the -308 GA genotype of TNFA (P=.001). None of the genotypes of the proinflammatory cytokines were related to sex, the presence of atopy, asthma, or aspirin intolerance (P>.05).

CONCLUSION

The IL1A (4845 GT and 4845 TT), IL1B (-511 CC), and TNFA (-238 AA and -308 GA) genotypes were associated with susceptibility to NP in our study population.

Argl6gly polymorphism of the beta2-adrenoceptor gene (ADRBeta2) as a susceptibility factor for nasal polyposis

BACKGROUND

Nasal polyposis is probably a multifactorial disease, but so far, no genetic susceptibility factor has been identified. The observed associations between the ADRB2 argl6gly polymorphism and asthma-related phenotypes as well as those between nasal polyposis and asthma have prompted us to evaluate the potential involvement of this polymorphism in sinonasal polyposis.

METHODS

We enrolled in our study, 56 patients and 47 sex- and age-matched controls. Genomic DNA from cases and controls was extracted and genotype was assessed by a polymerase chain reaction amplification/Nco I digestion assay. Statistical analysis was performed using JMP software (version 5.1).

RESULTS

The "number of arg alleles" is significantly higher in cases than in controls (p = 0.0386 at t-test; substantially confirmed by nonparametric tests, p = 0.0396 by Wilcoxon/Kruskal-Wallis tests).

CONCLUSION

Although results of this study are preliminary because of the small size of the sample, the arg16 allele seems to be associated with an increased risk of sinonasal polyposis suggesting ADRB2 as a susceptibility gene. This finding, if confirmed, would have a clinical value in helping to assess the genetic risk for sinonasal polyposis thus opening new perspectives for the study of molecular factors underlying the development of nasal polyps.

The expression of MUC5AC and MUC5B mucin genes in the mucosa of chronic rhinosinusitis and nasal polyposis

BACKGROUND

The aim of this study was to investigate the expression of MUC5AC and MUC5B messenger RNAs (mRNAs) and localization of these proteins in human sinus mucosa of chronic rhinosinusitis (CRS) and CRS with nasal polyposis (CRS/NP).

METHODS

Maxillary sinus ostia mucosa was harvested from patients undergoing endoscopic sinus surgery for CRS, CRS/NP, and non-CRS pathologies (control). Then, sinus mucosa was analyzed using reverse-transcription polymerase chain reaction to detect mRNA of MUC5AC and MUC5B. Hematoxylin and eosin staining and immunofluorescent staining were used to localize MUC5AC and MUC5B proteins in the sinus mucosa.

RESULTS

mRNAs of MUC5AC and MUC5B in the sinus mucosa of CRS and CRS/NP were significantly increased compared with that in normal sinus mucosa (p < 0.01), and no significant difference was found between the mucosa of CRS and that of CRS/NP (p > 0.05). MUC5AC protein was expressed mainly in the goblet cells, and MUC5B expression was located in the submucosal glands cells and the epithelia of sinus mucosa. ARPC in staining of MUC5AC and MUC5B were found no different between the CRS group and the CRS/NP group (p > 0.05), whereas they were significantly lower in the normal group compared with the other two groups, respectively (p < 0.05).

CONCLUSION

This study showed that MUC5AC and MUC5B mucin genes were up-regulated in sinus mucosa of CRS and CRS/NP. MUC5AC and MUC5B may play an important role in the pathogenesis of CRS and NP.

Ligneous conjunctivitis: a clinicopathological, immunohistochemical, and genetic study including the treatment of two sisters with multiorgan involvement

Ligneous conjunctivitis (LC) is a rare disease characterized by wood-like pseudomembranes developing on the ocular and extraocular mucosae secondary to plasminogen (PLG) deficiency. In this paper, we report two cases of LC in two sisters of 57 and 62 years of age that presented with recurrent, bilateral pseudomembranes on conjunctiva and a history of consanguinity and deafness. Pseudomembranes showed superficial and/or subepithelial deposits of eosinophilic amorphous hyaline, amyloid-like material with a variable proportion of granulation tissue, and inflammatory cells. The eosinophilic deposits were negative for Congo red stain, immunoreactive for fibrinogen, and consistently negative for amyloid A component, transthyretin, beta(2)-microglobulin, albumin, fibronectin, collagen type IV, vimentin, and cytokeratins. Among inflammatory cells, a percentage of positivity of roughly 60% for lymphocytes T (CD3+) and 40% for lymphocytes B (CD8+), with a relation of cytotoxic/helper (CD8/4) T cells of 3:2, was found. In one case, nasal polyps and recurrent gastric peptic ulcer were also characterized by the same subepithelial hyaline deposits. A novel homozygous point mutation c.1856 C>T was found in exon 15 of the PLG gene in both patients. Amniotic membrane transplantation was done in one case with promising results.

Sinonasal surfactant protein A1, A2, and D gene expression in cystic fibrosis: a preliminary report

OBJECTIVE

To measure alterations in SPA1, A2, and D gene expression in various forms of inflammatory chronic rhinosinusitis (CRS).

STUDY DESIGN AND SETTING

Sinus mucosal biopsies were performed in patients with allergic fungal rhinosinusitis (AFS), CRS with nasal polyposis, cystic fibrosis (CF), and controls. SP mRNA was measured with quantitative polymerase chain reaction.

RESULTS

Patients with CF (n = 4) showed significantly increased SPA1 (82-fold), SPA2 (100-fold), and SPD (47-fold) mRNA (P < 0.05) when compared with controls (n = 5). Patients with CRS with nasal polyposis (n = 5) also demonstrated elevated SPA1 (27-fold), SPA2 (13-fold), and SPD (13-fold). Patients with AFS (n = 7) had increased SPA1 (5-fold), SPA2 (9-fold), and SPD (17-fold), but were not statistically significant.

CONCLUSION

SPA1, A2, and D are upregulated in various forms of CRS, but are significantly elevated in cystic fibrosis CRS.

SIGNIFICANCE

Understanding the role of SPs in CRS will help develop novel treatment approaches for sinonasal pathoses.

[Genetic epidemiologic study on nasal polyps]

OBJECTIVE

To investigate the genetic mode of nasal polyp and the effect of genetic factor on occurrence of the disease.

METHODS

A genetic epidemiological case-control study including 280 pedigrees (120 nasal polyp cases and 160 controls) was conducted. The segregation ratio and the heritability of nasal polyp were respectively estimated by the Li-Mantel-Gart method and the Falconer method.

RESULTS

The segregation ratio was 0.124 (95% CI 0.081-0.167), significantly lower than 0.25, which showed that nasal polyp did not possess the characteristics of monogenetic model. The prevalence rate of first-degree and second-degree relatives in cases were 8.571% and 3.086% respectively, which were significantly different (X2 = 24.851, P < 0.01) and were higher than that noticed 1.376% and 1.141% in controls (X2 = 33.547 and 14.274, all P < 0.01). The heritability of the first-degree and second-degree relatives of nasal polyp was 64.488% and 61.947%. Among the first-degree relatives of nasal polyp probands, the heritability of the adult group and the children group were respectively 60.735% and 74.598% (the difference was significant, X2 = 4.504, P < 0.05). The heritability of the first-occurred group was 62.839% and the recurred group was 74.304% (the difference was significant, X2 = 4.105, P < 0.05).

CONCLUSIONS

This study indicated that the genetic model of nasal polyp belonged to polygenetic and the genetic factors played an important role in the occurrence of nasal polyp, especially for young or recurred patients.

Tumor necrosis factor-alpha stimulates the expression of C-C chemokine ligand 2 gene in fibroblasts from the human nasal polyp through the pathways of mitogen-activated protein kinase

BACKGROUND

Recruitment of macrophages is crucial to the pathogenesis of the nasal polyp (NP) because this disease is believed to be inflammation related. Information regarding the expression of C-C chemokine ligand 2 (CCL2), an essential modulator of monocyte chemotaxis in nasal polyp fibroblasts (NPFs), remains unavailable. In this study, the effects of tumor necrosis factor (TNF)-a on CCL2 expression in NPFs and the signaling pathway involved were investigated.

METHODS

Primary cultures of NPFs were established from NPs. The expressions of CCL2, c-Fos, and c-Jun mRNAs in NPF after TNF-a stimulation were detected by Northern blot. Western blot was used to examine the activation of mitogen-activated protein kinase (MAPK) signaling pathways. Activator protein (AP) 1/DNA interactions were evaluated by electrophoretic mobility shift assay (EMSA).

RESULTS

Northern blot showed that TNF-alpha stimulated CCL2 gene expression in NPFs. Significant increase of B-Raf, phosphorated MAPK including mitogen-activated ERK-activate kinase (MEK)1/2, extracellular signal-related kinase 1/2, and p38 were detected by Western blot. c-Fos and c-Jun mRNAs were induced by TNF-alpha, and PD98059 (MEK inhibitor) and SB203580 (p38 inhibitor) abolished the up-regulation of c-Fos. EMSA revealed that TNF-a increased AP-1/DNA binding, and PD98059 and SB203580 attenuated this reaction, possibly via reducing c-Fos synthesis. PD98059 and curcunmin (AP-1 inhibitor) markedly suppressed the TNF-alpha-induced CCL2 expression, whereas the effect of SB203580 was less noted.

CONCLUSION

TNF-alpha induces CCL2 transcription in NPFs. B-Raf/MEK/ERK signaling cascade and to a less extent the p38 pathway are responsible for c-Fos activation and the subsequent AP-1/DNA interaction leading to CCL2 expression.

Microarray cDNA to identify inflammatory genes in nasal polyposis

BACKGROUND

The objective of this study was to investigate the spectrum of inflammatory gene expression in patients with nasal polyposis.

METHODS

The cDNA microarray technique was used to identify gene expression in tissue samples from nasal polyps and adjacent inflammatory nasal mucosa of 21 patients with nonallergic nasal polyposis. To validate the microarray analysis, we compared the expression of five genes by reverse transcription-polymerase chain reaction (RT-PCR): tumor necrosis factor, IL-5, IL-9, fibroblast growth factor, and transforming growth factor (TGF)-beta1.

RESULTS

We tested 96 different inflammatory genes in our samples. Thirty-six genes exhibited differences in expression between the two tissue types. In all 36 genes the level of expression was greater in the inflammatory mucosa than the polyps. The RT-PCR confirmed the cDNA results.

CONCLUSION

We believe that the high expression of TGF-beta1 in inflammatory mucosa compared with the low expression in polyps may reflect an important role in the inhibitory mechanisms of nasal polyposis.

Alpha and beta glucocorticoid receptors: relevance in airway diseases

Glucocorticoids (GCs) are the most common and effective drugs for treating inflammatory airway respiratory diseases. Despite their efficacy, some patients respond poorly to GC treatment. Alterations in the expression of the receptor that mediates GC actions, the glucocorticoid receptor (GR), are one of the potential mechanisms that would explain GC insensitivity. In this review, we present an update on the GR gene and its products, namely GRalphaand GRbeta, as well as their alterations in disease. GRalpha has a widespread distribution and is responsible for the induction and repression of target genes, whereas GRbeta can act as a dominant negative inhibitor of GRalpha-mediated transactivation and transrepression. Very low GRbeta mRNA levels have been detected in a number of cells and tissues, which often contradict GRbeta protein data. Nevertheless, an association between GC insensitivity and increased GRbeta expression has been reported in asthma, nasal polyposis, and ulcerative colitis, and in vitro, certain pro-inflammatory cytokines upregulate GRbeta expression. However, the role of GRbeta in modulating GC sensitivity in vivo has been highly debated and is as yet unclear.

Microarray analysis of allergic fungal sinusitis and eosinophilic mucin rhinosinusitis

OBJECTIVE

Our goal was to determine and compare the differential gene expression in allergic fungal sinusitis (AFS) and eosinophilic mucin rhinosinusitis (EMRS).

STUDY DESIGN AND SETTING

We conducted a complementary DNA microarray analysis of prospectively gathered tissue from a tertiary rhinology practice.

RESULTS

Compared to normal subjects, 38 genes or potential genes were differentially expressed in AFS patients, while 10 genes were differentially expressed in EMRS patients. Four genes differentially expressed in EMRS were not differentially expressed in AFS: cathepsin B, sialyltransferase 1, GM2 ganglioside activator protein, and S100 calcium binding protein. These genes mediate lysosomal activity and are known to have differential expression in inflammatory and neoplastic states.

CONCLUSIONS

EMRS and AFS show some similarities in gene expression profiles using microarray analysis. Significant differences in gene expression in both EMRS and AFS patients compared with normal subjects provide early clues to the pathophysiology of EMRS and AFS.

SIGNIFICANCE

This study demonstrates that complementary DNA microarray analysis is a feasible tool for studying different disease subclassifications and is the first to study these subclasses in chronic rhinosinusitis.

The up-regulated expression of tenascin C in human nasal polyp tissues is related to eosinophil-derived transforming growth factor beta1

BACKGROUND

Tissue remodeling is an important characteristic of nasal polyps (NPs). However, the mechanisms underlying the remodeling processes are poorly defined. This study investigated the role of transforming growth factor (TGF) beta1 and eosinophils in the expression of tenascin C (Tn-C), an extracellular matrix glycoprotein, in NPs.

METHODS

The protein expression of Tn-C and TGF-beta1 was examined by means of immunohistochemistry in NPs and normal control inferior turbinate tissues. Furthermore, cell culture, quantitative RT-PCR, and in situ immunocytofluorescence techniques were used to investigate the direct effect of TGF-beta1 and eosinophils on Tn-C production in primary nasal epithelial cells.

RESULTS

Tn-C protein expression was significantly up-regulated in NP tissues and correlated with TGF-beta1+ eosinophils. TGF-beta1 and eosinophils dramatically induced Tn-C mRNA and protein expression in nasal epithelial cells. The effect of eosinophils could be inhibited partly by a neutralizing antibody to TGF-beta1.

CONCLUSION

Eosinophil-derived TGF-beta1 may contribute, at least in part, to the tissue remodeling in NPs.

Do nasal polyps and inverted papilloma have similar disorders in cell cycle regulation?

BACKGROUND

The aim of this study was to determine the expression of cell cycle regulation genes in patients with inverted papilloma (IP) and compare this with expression in patients with nasal polyps (NPs).

METHODS

Tissue from 18 patients with IP and 5 patients with NPs were stained by immunohistochemistry techniques for p53 and p27. Measurement of the gene expression was performed by three assessors, who we blinded with respect to the specimens.

RESULTS

The mean score for p53 expression (3.33) was significantly higher in the IP group than the NP group (1.46). The mean difference between IP and NPs was 1.80 (CI, 1.15-2.46; p = 0.003). Additionally, we showed in a number of individuals variation in the p53 expression within the same specimen. There was no difference in the mean scores for p27, with the mean difference 0.79 (CI, 0.30-1.89; p = 0.147).

CONCLUSION

Our study established a significantly increased expression of p53 in IP when compared with NPs. Additionally, there appear to be two different cell populations identified within the same specimens, which exhibited variation in their p53 expression.

Expression of cyclooxygenase-2 and 5-lipoxygenase in nasal polyps associated with interleukin-4 promoter polymorphism -590

OBJECTIVE

To evaluate expression of cyclooxygenase (COX)-2 and 5-lipoxygenase (5-LO) associated with interleukin (IL)-4 promoter polymorphism -590 in nasal polyp tissues.

STUDY DESIGN AND SETTING

A prospective controlled study. A venous blood sample was taken to determine the genotype in 61 nasal polyp subjects. The C-590T variant was determined by the polymerase chain reaction-restriction fragment length polymorphism method. The expression of 5-LO and COX-2 was determined with immunohistochemical staining in 37 nasal polyp tissues associated with genotype.

RESULTS

The genotype frequencies at position -590 of the IL-4 gene in the patients with nasal polyp were C/C (8.20%), C/T (40.98%), and T/T (50.82%). There was no significantly increased expression of COX-2 among genotypes. The 5-LO expression was significantly increased in C/C compared with C/T and T/T.

CONCLUSION

We suggested that the IL-4 promoter polymorphism -590 C/C is associated with the expression of 5-LO in the patients with nasal polyp.

Nasal and paranasal sinus endoscopy, computed tomography and microbiology of upper airways and the correlations with genotype and severity of cystic fibrosis

OBJECTIVE

Many studies have assessed clinical and functional aspects of lower airway affections in cystic fibrosis. Conversely, few studies have been performed to assess the clinical and functional affections of upper airways. The objective of the present study was to correlate the variables obtained by nasal and paranasal sinuses endoscopy, paranasal sinus laboratory and computed tomography (CT) scan findings, and to check the association with severity and genotype of cystic fibrosis patients.

METHODS

Clinical and laboratory study of 50 patients with cystic fibrosis at a university center. All patients were submitted to CT scan, nasal and paranasal endoscopy and bacterioscopy of maxillary sinus, trachea and oropharynx secretion. Severity of cystic fibrosis was assessed by Shwachman score and the most frequent genetic mutations were identified.

RESULTS

The prevalence of polyposis in the studied population was 36% and it was greater among homozygote for DeltaF 508. Shwachman score was correlated with age (p=0.003). The genotype was correlated with presence of nasal polyposis (p=0.006). There was no association between affections in CT scan and severity of cystic fibrosis (CF). Patients presented high prevalence of early colonization of Pseudomonas aeruginosa.

CONCLUSIONS

Sinus disease in CF patients presents several clinical, endoscopic and tomographic affections. Although most of them are not correlated with severity and disease genotype, severity of CF is correlated with age and presence of polyposis is genotype-dependent.

[Relationship between Staphylococcal superantigens and the dominant expression of T-cell receptor V beta gene in chronic rhinosinusitis with nasal polyp]

OBJECTIVE

To analyse the relationship between superantigens produced by Staphylococcus aureus and the mRNA expression of T-cell receptor V beta region (TCR Vbeta), and to investigate the possible role of Staphylococcal superantigens in the pathogenesis of nasal polyps.

METHODS

Sinonasal mucus and polyp/mucosa tissue were obtained from patients with chronic rhinosinusitis (22 patients with bilateral nasal polyps, 15 without nasal polyps) and 12 normal subjects as comparative negative controls. Mucus specimens were assayed by enzyme-linked immunosorbent assay (ELISA) for Staphylococcal exotoxins,and analyzed for the expression of TCR Vbeta genes using the technique of reverse transcriptase-polymerase chain reaction (RT-PCR).

RESULTS

The percentages of Staphylococcus exotoxins in nasal polyps were 54.54% (21/22) for chronic rhinosinusitis with nasal polyp (CRSwNP) subjects. There were no positive results in the CRSsNP or control groups. The expressional intensity of Vbeta3 (10.02), Vbeta14 (3.54), Vbeta15 (2.39), Vbeta17 (3.48), and Vbeta20 (2.94) was increased significantly for Staphylococcal exotoxin B (SEB) positive subjects (P < 0.05). Vbeta2 (13.8) and Vbeta6. 1-3 (6.53) were significantly highly expressed for toxic shock syndrome toxin-1 (TSTf-1) positive subjects in CRSwNP group (P < 0.05). There were no dominantly used Vbeta fragments in ELISA- negative specimens. In the group of chronic rhinosinusitis without nasal polyp (CRSsNP), most of TCR Vbeta gene subfamilies demonstrated a trend toward higher expressional levels compared with those of normal controls, although there was no statistical difference (P > 0.05).

CONCLUSIONS

There was relationship between Staphylococcal superantigens and the excursion of TCR Vbeta gene spectra in nasal polyp, and superantigens possibly play an important role in the pathogenesis of CRSwNP.

Overexpression of hepatocyte growth factor and its receptor c-Met in nasal polyps

OBJECTIVES

To investigate the expression and distribution of hepatocyte growth factor (HGF) and c-Met proteins in normal nasal mucosa and in nasal polyps and to evaluate the possible effects of HGF and c-Met on the development of nasal polyps.

DESIGN

Prospective study.

SETTING

Tertiary academic institution.

PATIENTS

Normal inferior turbinate mucosa was obtained from 20 patients undergoing surgery for augmentation rhinoplasty. Nasal polyps were obtained from 20 patients undergoing endoscopic sinus surgery for chronic polypoid sinusitis.

INTERVENTIONS

Semiquantitative reverse-transcriptase polymerase chain reaction, immunohistochemistry, and Western blot analysis were performed.

MAIN OUTCOME MEASURES

The expression and distribution of HGF and c-Met were analyzed.

RESULTS

Using immunohistochemistry, moderate to high levels of HGF were mainly localized in submucosal glands of nasal polyps, while c-Met was detected in submucosal glands and in epithelial cells. In normal turbinate mucosa, immunopositive HGF was detected in submucosal glands, where faint staining was found, while c-Met was noted in epithelial cells and in submucosal glands. Semiquantitative reverse-transcriptase polymerase chain reaction and Western blot analysis showed that HGF expression was increased in nasal polyps compared with that in normal turbinate mucosa. The same result was observed for c-Met.

CONCLUSION

Elevated c-Met expression in combination with expression of HGF in nasal polyps may enhance the proliferation of epithelial cells and submucosal glandular cells through the release of HGF, which activates c-Met receptors in nasal polyps.

Mucin genes have different expression patterns in healthy and diseased upper airway mucosa

BACKGROUND

Mucus hyper-secretion is a feature of several airways diseases such as chronic rhinosinusitis, asthma, and cystic fibrosis (CF). Since mucins are major components of mucus, the knowledge of their distribution and regulation in nasal tissues is likely to improve mucus hyper-secretion therapy.

OBJECTIVE

The aim of this study was to evaluate and compare mucin gene expression at epithelial and glandular levels, and to identify potential mucin expression patterns for specific upper airways pathologies.

METHODS

Immunohistochemistry for MUC1, MUC2, and MUC4-MUC8 mucins was performed on healthy nasal mucosa (NM; n=12), bilateral nasal polyps (NP; n=38), NP from CF patients (n=10), and antrochoanal (AC) polyps (n=11). MUC2, MUC4, MUC5AC, and MUC6 mRNA expression were also analysed by in situ hybridization.

RESULTS

MUC1, MUC4, and MUC5AC mucins were highly expressed in the epithelium and their expression pattern was similar in all NP types, MUC1 and MUC4 being increased and MUC5AC decreased compared with NM. MUC8 was highly detected at both epithelial and glandular levels with marked variability between groups. MUC5B was mainly detected in glands and the expression in all polyp types was higher than in NM. Moreover, MUC5B expression was higher in NP epithelia from CF patients than in bilateral NP and healthy NM. Although MUC2 expression was low, especially in AC polyps, it was detected in most samples. In NM, MUC6 and MUC7 were scarcely detected and MUC7 expression was restricted to glands.

CONCLUSIONS

These results suggest that NP have a different pattern of mucin expression than healthy NM and that CF polyps (increased MUC5B) and AC polyps (decreased MUC2) have a different mucin expression pattern than bilateral NP.

DQA1 and DQB1 association and nasal polyposis

OBJECTIVE

The aim of this study was to determine the contribution of the human major histocompatibility complex (HLA)-DQA1, -DQB1, and TNFalpha genes with simple nasal polyposis.

STUDY DESIGN AND SETTING

A comparative case-control study with 31 patients and 151 controls was performed. HLA-DQA1, -DQB1, and TNFalpha -238 promoter position loci were typed by polymerase chain reaction (PCR) and sequence specific oligonucleotide probes (SSOPs). TNFalpha -308 promoter position was determined by PCR and digestion with NcoI restriction enzyme.

RESULTS

The allele HLA-DQA1*0201 (P(c) = 0.019) had an etiologic fraction (EF) of 17%, whereas 13% EF was found for the haplotype HLA-DQA1*0201-DQB1*0201 (P = 0.016). Analysis of -DQB1 and TNFalpha promoter did not show significant differences between cases and controls.

CONCLUSIONS

HLA-DQA1*0201-DQB1*0201 haplotype is involved in susceptibility, conferring 5.53 times more risk of developing this disease.

EBM RATING

B-2b.

Nasal polyposis in Peutz-Jeghers syndrome: a distinct histopathological and molecular genetic entity

BACKGROUND

Peutz-Jeghers syndrome (PJS) is an autosomal dominant hamartomatous polyposis syndrome of the gastrointestinal tract, caused by a germline STK11/LKB1 mutation. Nasal polyposis was described in the original report by Peutz. Recently, a molecular-genetic association between nasal polyposis and PJS has been reported.

OBJECTIVE

To further explore the occurrence and pathogenesis of PJS-related nasal polyposis.

METHODS

51 patients with PJS, 84 unaffected family members and 36 spouses from 18 families with PJS were questioned for the presence of nasal polyposis. 12 PJS-related nasal polyps, 1 carcinoma of the nasal cavity and 28 sporadic nasal polyps were analysed for loss of (wild type) STK11/LKB1, eosinophilia, squamous metaplasia, dysplasia and expression of cyclo-oxygenase 2 and p53.

RESULTS

Nasal polyps occurred in 8 of 51 patients with PJS, and were not reported by non-affected family members (p<0.001). Germline STK11/LKB1 mutations were identified in all patients with PJS and nasal polyposis. Loss of heterozygosity was found in four of eight PJS-related nasal polyps, but not in sporadic nasal polyps (p = 0.002). PJS-related nasal polyps showed less eosinophilia than sporadic nasal polyps (p<0.001). Expression of cyclo-oxygenase 2 was found in 11 of 12 PJS-related nasal polyps and 19 of 28 sporadic nasal polyps (p>0.05). Overexpression of p53 was not found.

CONCLUSIONS

Nasal polyposis occurs in a significant number of Dutch patients with PJS, one of whom developed a carcinoma in the nasal cavity. The loss of heterozygosity, and the absence of eosinophilia suggest a distinct pathogenesis compared with sporadic nasal polyposis.

Expression of acidic fibroblast growth factor and basic fibroblast growth factor in nasal polyps

CONCLUSION

Up-regulated expression of acidic fibroblast growth factor (aFGF) and basic fibroblast growth factor (bFGF) in nasal polyps may be related to epithelial proliferation and neoangiogenesis associated with nasal polyp growth.

BACKGROUND AND OBJECTIVES

aFGF and bFGF are polypeptides that effect mitogenesis, neoangiogenesis and tissue repair. The purpose of this study was to investigate the expression of aFGF and bFGF at both the mRNA and protein levels in nasal polyps.

MATERIALS AND METHODS

Tissue samples of nasal polyp and inferior turbinate mucosae were obtained. Reverse transcriptase (RT)-PCR, in situ hybridization, and Western blotting for aFGF and bFGF were performed in nasal polyp and nasal inferior turbinate.

RESULTS

RT-PCR showed 50% aFGF and 29% bFGF expression positivity in 14 nasal polyps; however, 13 turbinates revealed no PCR products. aFGF and bFGF expression was localized to some inflammatory cells of nasal polyps by in situ hybridization. Western blotting identified aFGF and bFGF molecular masses of 18 kDa and 24 kDa, respectively, in nasal polyps, and these levels were higher than those observed in nasal turbinates. aFGF and bFGF proteins were also localized in some inflammatory cells of nasal polyps by immunostaining.

Familial aggregation of sinonasal polyps correlates with severity of disease

OBJECTIVE

Investigate familial aggregation of sinonasal polyps (NP) and correlate the severity of chronic rhinosinusitis (CRS) with a family history of NP.

STUDY DESIGN AND SETTING

A questionnaire documenting NP, asthma, or aspirin intolerance was completed by 174 CRS patients. Severity of sinus disease was stratified as isolated NP, NP with concomitant asthma, and Samter's triad (polyps, asthma, and aspirin intolerance).

RESULTS

Compared to controls, CRS patients had a higher incidence of a family history of NP. Additionally, patients stratified with severe CRS had a higher incidence of relatives with NPs.

CONCLUSIONS

Familial aggregation of NP is demonstrated in CRS patients and correlates with disease severity.

EBM RATING

B-2b.

Increased prevalence of interleukin-1 receptor antagonist gene polymorphism in patients with chronic rhinosinusitis

OBJECTIVE

To assess the association of the interleukin (IL)-1beta and the IL-1 receptor antagonist (IL-1Ra) gene polymorphisms with chronic rhinosinusitis (CRS).

DESIGN

Genotyping of the 2 IL-1beta gene (IL1B) polymorphisms (promoter and exon) and the IL-1Ra gene (IL1RN) polymorphism (intron 2) was performed using polymerase chain reaction and restriction length fragment polymorphism analyses.

SETTING

Prospective study, tertiary medical center.

PATIENTS

The study population comprised 88 consecutive adult Taiwan-Chinese patients who met stringent criteria for CRS and received endoscopic sinus surgery and 103 healthy volunteers of the same ethnicity and similar age range. Of the 88 patients, 61 had CRS with nasal polyps, while the other 27 had CRS without nasal polyps.

RESULTS

There were significant differences in the distribution of the IL1RN polymorphism between the control subjects and patients with CRS (P<.05). The II allele of IL1RN occurred more frequently in the CRS patient group, and the odds ratio for subjects with I/II genotype was 3.39 (95% confidence interval, 1.25-9.18). In the case of CRS without nasal polyps, the odds ratio for subjects with I/II genotype was further increased to 4.75 (1.39-16.25). There was no association between the other 2 polymorphisms of IL1B and CRS.

CONCLUSION

Increased prevalence of IL1RN polymorphism in patients with CRS suggests that this polymorphism, or a polymorphism in linkage disequilibrium with it, may be involved in the development of CRS.