[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.

[Expression of toll-like receptors signaling pathway in chronic rhinosinusitis with nasal polyps]

OBJECTIVE

To investigate the expression of Toll-like receptors (TLRs) signaling pathway in chronic rhinosinusitis (CRS) with nasal polyps.

METHOD

Gene microarray analysis was used to detect the expression of TLRs signaling pathway in CRS with nasal polyps.

RESULT

Of 19 differentially expressed (two fold changes), 4 genes were upregulated and 15 genes were downregulated.

CONCLUSION

The differentially expressed genes in TLRs signaling pathway may exert its effect in the pathogenesis of CRS. In addition, the roles of TLR9 and its agonists need further study.

[The expression of mucins gene in the human nasal polyps and allergic rhinitis]

OBJECTIVE

To detect the mucin gene (MUC2, MUC5AC, MUC5B, MUC18 and MUC19) expression in the nasal polyps, allergic rhinitis (AR) and the normal nasal mucosa in human. To investigate the role and clinical significance of mucin gene in the pathogenesis of nasal polyps and AR patients.

METHOD

We obtained samples from 35 cases of nasal polyps, 18 cases of AR inferior turbinate and 18 cases of simple nasal septum deviation inferior turbinate. Specimens were analyzed with RT-PCR and Real-time FQ-RT-PCR.

RESULT

The results of RT-PCR and FQ-RT-PCR showed that the expression of MUC5AC, MUC5B in nasal polyps and AR patients was significantly higher than that in normal mucosa (P<0.05). The expression of MUC5AC, MUC5B in nasal polyps was not significantly different from that in AR patients (P>0.05). The expression of MUC2, MUC18 in nasal polyps and AR was not significantly different from that in normal mucosa (P>0.05). And the results of RT-PCR for MUC19 expression in AR was higher than that in nasal polyps group and normal group (P<0.05 or P<0.01).

CONCLUSION

MUC5AC and MUC5B are highly expressed in epithelium of human nasal polyps and AR, and they take part in mucus over-secretion in nasal polyps and AR. The expression of MUC19 in AR was higher than that in nasal polyps group and normal group. It indicates that the secretion of MUC19 in allergic rhinitis was on high level. There was no difference of the expression of MUC2 and MUC18 in nasal polyps group, AR group and in normal group.

Alteration of mitochondrial DNA sequence and copy number in nasal polyp tissue

This study was designed to investigate the possibility that mtDNA mutations might arise in inflammatory or chronically damaged nasal polyp tissue from 23 patients. Thirteen patients (57%) displayed nasal polyp tissue-specific mtDNA mutations in the hypervariable segment of the control region and cytochrome b gene, which were not found in the corresponding blood cells and/or adjacent normal tissue. Nasal polyp tissue-specific length heteroplasmic mutations were also detected in nucleotide position (np) 303-315 homopolymeric poly C track (39%), np 514-523 CA repeats (17%) and np 16184-16193 poly C track (30%). The average mtDNA copy number was about three times higher in nasal polyp tissue than in the corresponding peripheral blood cells and adjacent non-polyp tissues. The level of reactive oxygen species (ROS) was significantly higher in the nasal polyp tissues compared to those from the corresponding samples. High level of ROS in nasal polyp tissue may contribute to development of mtDNA mutations, which may play a crucial role in the vicious cycle of pathophysiology of nasal polyps.

Hyperproliferation in nasal polyposis tissues is not associated with somatic genomic instability

BACKGROUND

Nasal polyps (NPs) are abnormal lesions that arise from any portion of the nasal mucosa or paranasal sinuses within the nasal cavities. They are characterized by the formation of inflammatory swellings of unstable respiratory mucosa, which protrude into the nasal cavity. The causes and the pathogenesis of NP development are not well understood. The current and principal hypothesis is that NPs result from allergy and inflammation, which cause an unstable respiratory mucosa with increased epithelial cell proliferation and epithelial morphologic changes.

OBJECTIVE

To understand if epithelial cell hyperproliferation can lead to acquired genomic instability and if nasal polyposis is a consequence of acquired chromosomal alterations in hyperproliferative nasal epithelia.

MATERIALS AND METHODS

To test this hypothesis and to perform a survey of chromosomal aberrations in nasal polyps, we applied array comparative genome hybridization (aCGH; 1 Mb resolution, made of 2464 bacterial artificial chromosome (BAC), P1 derived artificial chromosome (PAC), and P1 clones spanning the whole human genome) to deoxyribonucleic acid (DNA) obtained from the NPs of nine patients. The patients recruited in this study had been analyzed for Ki-67 expression using the MIB-1 antibody as a marker of proliferation and were chosen to represent a wide range of hyperproliferative status.

RESULTS

After data analysis, no chromosomal aberrations were detected by aCGH.

CONCLUSIONS

Our data do not support the hypothesis that nasal polyposis is a consequence of acquired chromosomal alterations in hyperproliferative nasal epithelia.

Effect of glucocorticoid on the MUC4 gene in nasal polyps

OBJECTIVES/HYPOTHESIS

Among the airway mucin genes, the MUC4 gene is an important gene in its response to inflammatory diseases of the upper airway. However, the expression and regulation of the MUC4 gene in the nasal polyps remains unclear.

STUDY DESIGN

The purpose of this study was to evaluate the expression of MUC4 mRNA and synthesis of mucin glycoprotein in the nasal polyps before and after treatment with a topical steroid in vivo and in vitro.

METHODS

Nasal polyps were obtained from 20 patients with chronic rhinosinusitis and were subsequently cultured. The level of MUC4 mRNA was measured by reverse-transcription polymerase chain reaction, and the amount of the MUC4 mucin glycoprotein was estimated by the enzyme-linked immunosorbent assay method.

RESULTS

The expression of MUC4 mRNA was found to be significantly higher in the nasal polyps than in the inferior turbinate (P < .05). The addition of interleukin (IL)-1 beta and lipopolysaccharide (LPS) increased the expression of MUC4 mRNA and mucin glycoprotein synthesis in cultured nasal polyp epithelial cells. Treatment with glucocorticoid inhibited the expression of MUC4 mRNA in the nasal polyps; it also inhibited the expression of IL-1 beta and LPS-induced MUC4 mRNA and mucin glycoprotein synthesis in cultured nasal polyp epithelial cells. The inhibitory effects of glucocorticoid were restored by treatment with a glucocorticoid receptor antagonist (RU-486).

CONCLUSIONS

These results suggest that the MUC4 gene is expressed in the nasal polyps and that glucocorticoid can control the expression of the MUC4 gene and mucin glycoprotein synthesis.

Nasal polyposis: is there an inheritance pattern? A single family study

BACKGROUND

Nasal Polyposis (NP) is defined as a chronic inflammatory disease of sinonasal mucosa leading to diffuse formation of benign polyps. Although family histories are frequently suggested in medical literature, no specific study focused on this point has been reported. The purpose of this study is to determine whether a hereditary factor could be implied for NP in a family where several members were affected. We included 99 members of this family.

METHODS

All patients were assessed for conditions known to be associated with the development or presence of NP. Concerning NP, patients were screened with a validated questionnaire and selected patients had a medical examination by an Ear, Nose and Throat practitioner.

RESULTS

Thirteen patients had a personal history of NP without asthma, aspirin intolerance, Churg Strauss syndrome, cystic fibrosis, Young's syndrome, bare lymphocyte syndrome, or primary ciliary dyskinesia. Within this family, 19.7% of those older than 17 years were affected by NP, as compared with the national French prevalence of 2.1%.

CONCLUSIONS

Regarding the pedigree, we discuss different modes of inheritance. The presence of consanguineous unions in this family suggests the possibility of a common ancestor and thus a recessive autosomal mode of inheritance.

[Gene expression profiles in human nasal polyps studied by DNA microarray]

OBJECTIVE

To explore the changes in gene expressions in the human nasal polyp.

METHOD

A 14500 gerie DNA microarray (Affymetrix) was used to examine gene expressions in 6 NP samples, 6 normal mucosal samples. The differentially expressed genes were identified and subjected to realtime PCR analysis.

RESULTS

The differentially expressed genes mostly involved in cytokines, adhesion genes about complements and their receptors, immune transcription regulatory molecules, signal transduction, differentially expressed genes including IL-8, RGS1, GRK4, CCL20, uteroglobin. The results of IL-8, RGS1 Real-time PCR of were consistent with that of gene chip analysis.

CONCLUSION

Microarray expression profile of NP samples is differential. RGS1 may play an important role in cell signal transduction, IL-8 may involve in occurrence of nasal polyps by inducing cells releasing inflammatory factors.

RKIP and BRAF aberrations in human nasal polyps and the adjacent turbinate mucosae

BACKGROUND

Little is known about the implication of BRAF and RKIP expression, or about the incidence of BRAF mutations in the formation of nasal polyposis.

OBJECTIVES

To determine the expression levels of the genes BRAF and RKIP, and to inspect the frequency of BRAF mutations in exons 11, 14 and 15 in human nasal polyps (NP).

PATIENTS AND METHODS

We analyzed 24 human NP specimens and their adjacent inferior and middle turbinates (AIT and AMT), as well as 14 control subjects [bearing 14 Control Inferior Turbinates (CIT) and 14 Control Middle Turbinates (CMT), in total]. The expression pattern of BRAF and RKIP was assessed with real-time RT-PCR. A real-time allele-specific PCR method, in combination with direct sequencing, was performed in order to inspect the frequency of the V600E mutation in exon 15, and to examine mutation status within exons 11 and 14.

RESULTS

The control mucosae presented significantly higher mRNA levels for both genes, compared to the NP and the AIT-AMT. Moreover, in NP, AIT and AMT, RKIP was found to present higher mRNA levels, in relation to the equivalent values of the BRAF gene (P=0.003 in NP; P<0.001 both in AIT and AMT). No mutation was detected in exon 14, whereas a silent mutation (A1380G, G460G) was noted for one NP sample in exon 11. Another NP sample was found to carry two mutations, one T1799A (V600E) and one A1801G (K601E). A significant co-expression of the two genes was noted in NP (P=0.012) and AIT (P=0.019).

CONCLUSION

The results of the expression levels of RKIP and BRAF, reflect the strong connection between the two genes. RKIP could play an important role in the down-regulation of wild-type BRAF, serving thus as an endogenous inhibitor of the MAPK pathway in nasal polyps and their adjacent turbinate mucosa.

[Research of gene chip detection and gene expression profile of nasal polyps]

OBJECTIVE

To investigate the gene expression profile by using gene chip technology and probe into the role of corresponding gene in the pathogenesis of nasal polyps by analysing the difference of the gene depression.

METHOD

The total RNAs were respectively extracted from 6 pairs of inferior turbinates and nasal polyps, and then were reversely transcribed to cDNAs with incorporation of fluorescent dUTP as the hybridization probes. The mixed probes were then hybridized with the BiostarH-40 s gene chips, it was scanned by laser scanner and the acquired image was analyzed by software.

RESULT

1887 genes were differently expressed in gene profile of nasal polyps, among which 1099 were upregulated and 788 were down-regulated. Six genes were found in all gene chips, among which 4 genes were upregulated and 2 were down-regulated. The 6 genes encoded the protein of the transmembrane 4 superfamily, highly similar to GAMMA-interferon-inducible protein IP-30 precursor, highly similar to complement factor I precursor and insulin-like growth factor binding protein 3 (IGFBP3).

CONCLUSION

Detecting the differently expressed genes will provide clues and theoretical foundation for the pathogenesis of nasal polyps. The nasal polyps is a polygenic disease and the genes of GAMMA-interferon-inducible protein, insulin-like growth factor binding protein may play an important role in its pathogenesis.

Expression analysis of VEGFA, FGF2, TGFbeta1, EGF and IGF1 in human nasal polyposis

A better understanding of the expression profile of a group of angiogenic markers in nasal polyps (NPs) would contribute considerably to the investigation of the formation of NPs. The aim of this study was to evaluate the combined mRNA expression of vascular endothelial growth factor A (VEGFA), fibroblast growth factor 2 (FGF2), transforming growth factor beta1 (TGFbeta1), epidermal growth factor (EGF) and insulin-like growth factor 1 (IGF1) in NPs obtained from 21 patients undergoing nasal polypectomy. Nasal mucosae were obtained from the adjacent inferior turbinates (AIT) and middle turbinates (AMT) of the patients, as well as from 11 control subjects undergoing nasal corrective surgery. Analysis was performed using real-time RT-PCR. VEGFA, TGFbeta1 and IGF1 exhibited significant over-expression in the NPs compared to the control turbinates, EGF did not exhibit significant expression, and FGF2 presented constant over-expression in the NPs compared to both the adjacent and control turbinates. Since its mRNA levels were positively correlated with all the corresponding levels of the rest of the growth factors studied, TGFbeta1 seems to be a key cytokine in interactions between NP cells and the leading molecule of the epithelial differentiation and tissue remodelling present in the disease. Many correlations between the transcript levels of the other growth factors arose in the NP group as well, supporting a co-regulation of these genes in nasal polyposis. Our conclusions were that that VEGFA and TGFbeta1 participate significantly in the formation of NPs, whereas FGF2 and IGF1 are implicated in nasal polyposis to a lesser, but still significant, extent. EGF does not seem to be actively involved in the NP evolution process.

(CCTTT)n polymorphism of NOS2A in nasal polyposis and asthma: a case-control study

BACKGROUND

Nitric Oxide (NO) has been proposed as an important signaling molecule. NO produced by the inducible NO synthase enzyme NOS2A is generated at high levels in certain types of inflammation. A pentanucleotide polypyrimidine microsatellite CCTTT has been identified in the promoter region of the NOS2A gene.

OBJECTIVE

The aim of this study was to analyze the (CCTTT)n polymorphism in patients with asthma and nasal polyposis.

MATERIAL AND METHODS

The study included 292 white individuals (194 patients and 98 controls). Asthma was diagnosed according to American Thoracic Society criteria and classified in accordance with the guidelines of the Global Initiative for Asthma. Skin prick tests were performed in all individuals. The polymorphism was analyzed by an electrophoretic method and by direct sequencing.

RESULTS

A significant association was detected for a 15-repeat cutoff in nasal polyposis (Fisher P value = .0001, Monte Carlo P value [after 10(4) simulations] = .002). Multivariate analysis adjusted for age and sex confirmed this association with an increased risk of nasal polyposis (odds ratio, 14.39; 95% confidence interval, 3.02-68.60; P = .001).

CONCLUSION

The number of CCTTT repeats in the promoter region of NOS2A could be associated with the inflammatory process of nasal polyposis in our population. Modifications of NOS2A transcription levels could be involved in this association.

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.