E3 ubiquitin ligase NEDD4L inhibits epithelial-mesenchymal transition by suppressing the ß-catenin/HIF-1α positive feedback loop in chronic rhinosinusitis with nasal polyps.

Chronic rhinosinusitis with nasal polyp (CRSwNP) is a refractory inflammatory disease with epithelial-mesenchymal transition (EMT) as one of the key features. Since ubiquitin modification has been shown to regulate the EMT process in other diseases, targeting ubiquitin ligases may be a potential strategy for the treatment of CRSwNP. In this study we investigated whether certain E3 ubiquitin ligases could regulate the EMT process in CRSwNP, and whether these regulations could be the potential drug targets as well as the underlying mechanisms. After screening the potential drug target by bioinformatic analyses, the expression levels of three potential E3 ubiquitin ligases were compared among the control, eosinophilic nasal polyp (ENP) and non-eosinophilic nasal polyp (NENP) group in clinical samples, and the significant decrement of the expression level of NEDD4L was found. Then, IP-MS, bioinformatics and immunohistochemistry studies suggested that low NEDD4L expression may be associated with the EMT process. In human nasal epithelial cells (hNECs) and human nasal epithelial cell line RPMI 2650, knockdown of NEDD4L promoted EMT, while upregulating NEDD4L reversed this effect, suggesting that NEDD4L inhibited EMT in nasal epithelial cells. IP-MS and Co-IP studies revealed that NEDD4L mediated the degradation of DDR1. We demonstrated that NEDD4L inhibited the ß-catenin/HIF-1α positive feedback loop either directly (degrading ß-catenin and HIF-1α) or indirectly (mediating DDR1 degradation). These results were confirmed in a murine NP model in vivo. This study for the first time reveals the regulatory role of ubiquitin in the EMT process of nasal epithelial cells, and identifies a novel drug target NEDD4L, which has promising efficacy against both ENP and NENP by suppressing ß-catenin/HIF-1α positive feedback loop.

Distinct expression of SARS-CoV-2 receptor ACE2 correlates with endotypes of chronic rhinosinusitis with nasal polyps.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) entry factors, ACE2 and TMPRSS2, are highly expressed in nasal epithelial cells. However, the association between SARS-CoV-2 and nasal inflammation in chronic rhinosinusitis with nasal polyps (CRSwNP) has not been investigated. We thus investigated the expression of SARS-CoV-2 entry factors in nasal tissues of CRSwNP patients, and their associations with inflammatory endotypes of CRSwNP. METHODS: The expression of ACE2 and TMPRSS2 was assessed in nasal tissues of control subjects and eosinophilic CRSwNP (ECRSwNP) and nonECRSwNP patients. The correlations between ACE2/TMPRSS2 expression and inflammatory indices of CRSwNP endotypes were evaluated. Regulation of ACE2/TMPRSS2 expression by inflammatory cytokines and glucocorticoids was investigated. RESULTS: ACE2 expression was significantly increased in nasal tissues of nonECRSwNP patients compared to ECRSwNP patients and control subjects, and positively correlated with the expression of IFN-γ, but negatively correlated with tissue infiltrated eosinophils, and expression of IL5 and IL13. IFN-γ up-regulated ACE2 expression while glucocorticoid attenuated this increase in cultured nasal epithelial cells. Genes co-expressed with ACE2 were enriched in pathways relating to defence response to virus in nasal tissue. TMPRSS2 expression was decreased in nasal tissues of CRSwNP patients compared to control subjects and not correlated with the inflammatory endotypes of CRSwNP. Glucocorticoid treatment decreased ACE2 expression in nasal tissues of nonECRSwNP patients, but not in ECRSwNP patients, whereas TMPRSS2 expression was not affected. CONCLUSION: These findings indicate that ACE2 expression, regulated by IFN-γ, is increased in nasal tissues of nonECRSwNP patients and positively correlates with type 1 inflammation.

The ratio of 11ß-hydroxysteroid dehydrogenase 1/11ß-hydroxysteroid dehydrogenase 2 predicts glucocorticoid response in nasal polyps.

BACKGROUND: Glucocorticoids are the first-line medical treatment for chronic rhinosinusitis with nasal polyps (CRSwNP), whose local metabolism is catalyzed by 11ß-HSD1 and 11ß-HSD2. This study investigates the role of 11ß-HSD1 and 11ß-HSD2 on the glucocorticoid response of CRSwNP patients and the pathogenic mechanism of these polyps. METHODS: Forty-three adult CRSwNP patients were enrolled in this study. We evaluated the endoscopic scores by a nasal polyp grading system before and after treatment. We estimated the response to glucocorticoids by the total endoscopic scores. The logistic regression models and inflammatory characteristic curves were conducted to explore the prediction of the response to glucocorticoid in CRSwNP. The expression of 11ß-HSD1 and 11ß-HSD2 on human sinonasal epithelial cells (HSECS) was measured under the stimulation of toll-like receptor agonists and dexamethasone. RESULTS: The endoscopic scores in the CRSwNP group declined, the expression of 11ß-HSD1/11ß-HSD2 increased (r = 0.5276, P = 0.0011), and the cutoff value of the ratio of 11ß-HSD1/11ß-HSD2 was 0.4654 (sensitivity 79.17%, specificity 88.89%). Dexamethasone induced a decrease in the ratio of 11ß-HSD1/11ß-HSD2 (P = 0.049) by the stimulation of PGN-BS. CONCLUSION: We found a strong correlation between the response to glucocorticoids and the ratio of 11ß-HSD1/11ß-HSD2, which could be used as a marker in predicting the level of tissue response to glucocorticoid therapy in CRSwNP. In addition, PGN-BS could also be a therapeutic target, as it is the negative factor that will decrease the sensitivity of glucocorticoids by reducing the ratio of 11ß-HSD1/11ß-HSD2.

Effects of Erythromycin on the Proliferation and Apoptosis of Cultured Nasal Polyp-Derived Cells and the Extracellular Signal-Regulated Kinase (ERK)/Mitogen-Activated Protein Kinase (MAPK) Signaling Pathway.

BACKGROUND Erythromycin and its derivatives have been used to treat nasal polyposis and reduce inflammation, but the mechanism of action remains unclear. The extracellular signal-regulated kinase (ERK) and mitogen-activated protein kinase (MAPK) pathway proteins are expressed in nasal polyps. The aim of this study was to investigate the effects of erythromycin on cell proliferation, apoptosis, and the expression of p-MEK1 and p-ERK1 on cultured nasal polyp-derived cells. MATERIAL AND METHODS Nasal polyp-derived cells (n=32) and control cells from normal inferior turbinate tissue (n=32) were divided into four groups: the control group; the erythromycin-treated (100 µM) group; the selumetinib-treated (2 nM) group; and the erythromycin + selumetinib-treated group. Western blot was used to detect p-MEK1 and p-ERK1 proteins. Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect mRNA expression of BCL-2 and BAX. Flow cytometry detected expression of Ki-67 and cell apoptosis. Cell apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick end-labeling (TUNEL). Spectrophotometry assessed caspase-3 activity. RESULTS The expression of Ki-67 was significantly increased, and cell apoptosis was significantly reduced in untreated nasal polyp-derived cells compared with controls. Erythromycin treatment significantly decreased cell proliferation and the expression of p-MEK1 and p-ERK1, and increased apoptosis in nasal polyp-derived cells compared with control cells. Selumetinib treatment had a synergistic effect with erythromycin to reduce the expression of p-MEK1 and p-ERK1, reduce cell proliferation, and increase cell apoptosis. CONCLUSIONS In cultured cells derived from nasal polyps, erythromycin treatment reduced cell proliferation and increased apoptosis by inhibiting the activation of the ERK/MAPK signaling pathway.

Hyaluronan synthases and hyaluronidases in nasal polyps.

Nasal polyps (NPs) are benign lesions of nasal and paranasal sinuses mucosa affecting 1-4 % of all adults. Nasal polyposis affects the quality of patient's life as it causes nasal obstruction, postnasal drainage, purulent nasal discharge, hyposmia or anosmia, chronic sinusitis, facial pain and snoring. Without treatment, the disease can alter the craniofacial skeleton in cases of extended growth of polyps. The development of NPs is caused by the hyperplasia of nasal or paranasal sinuses mucosa, and edema of extracellular matrix. This is usually the result of high concentration of high molecular mass hyaluronan (HA) which is either overproduced or accumulated from blood supply. The size of HA presents high diversity and, especially in pathologic conditions, chains of low molecular mass can be observed. In NPs, chains of about 200 kDa have been identified and considered to be responsible for the inflammation. The purpose of the present study was the investigation, in NPs and normal nasal mucosa (NM), of the expression of the wild-type and alternatively spliced forms of hyaluronidases, their immunolocalization, and the expression of HA synthases to examine the isoform(s) responsible for the increased amounts of HA in NPs. Hyaluronidases' presence was examined on mRNA (RT-PCR analysis) and protein (immunohistochemistry) levels. Hyaluronan synthases' presence was examined on mRNA levels. Hyaluronidases were localized in the cytoplasm of epithelial and inflammatory cells, as well as in the matrix. On mRNA level, it was found that hyal-1-wt was decreased in NPs compared to NM and hyal-1-v3, -v4 and -v5 were substantially increased. Moreover, HAS2 and HAS3 were the only hyaluronan synthases detected, the expression of which was almost similar in NPs and NM. Overall, the results of the present study support that hyaluronidases are the main enzymes responsible for the decreased size of hyaluronan observed in NPs; thus they behave as inflammatory agents. Therefore, they could be a potential target for the design of a more advanced treatment for nasal polyposis.

Neuronal NOS localises to human airway cilia.

BACKGROUND: Airway NO synthase (NOS) isoenzymes are responsible for rapid and localised nitric oxide (NO) production and are expressed in airway epithelium. We sought to determine the localisation of neuronal NOS (nNOS) in airway epithelium due to the paucity of evidence. METHODS AND RESULTS: Sections of healthy human bronchial tissue in glycol methacrylate resin and human nasal polyps in paraffin wax were immunohistochemically labelled and reproducibly demonstrated nNOS immunoreactivity, particularly at the proximal portion of cilia; this immunoreactivity was blocked by a specific nNOS peptide fragment. Healthy human epithelial cells differentiated at an air-liquid interface (ALI) confirmed the presence of all three NOS isoenzymes by immunofluorescence labelling. Only nNOS immunoreactivity was specific to the ciliary axonemeand co-localised with the cilia marker ß-tubulin in the proximal part of the ciliary axoneme. CONCLUSIONS: We report a novel localisation of nNOS at the proximal portion of cilia in airway epithelium and conclude that its independent and local regulation of NO levels is crucial for normal cilia function.

Glycogen synthase kinase 3 in chronic rhinosinusitis: two faces of a single enzyme in one disease.

BACKGROUND: The origin and pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP) remain unclear. Glycogen synthase kinase 3 (GSK-3) is a unique multitasking kinase involved in the regulation of inflammation and apoptosis and is an important messenger in the downstream signaling of interleukin 6. OBJECTIVE: To analyze the possible role of GSK-3 in the pathogenesis of CRSwNP. METHODS: We examined tissue samples of nasal polyps and the inferior turbinate of patients with CRSwNP and the inferior turbinate of individuals without chronic sinusitis (healthy mucosa). Expression levels of GSK-3 and its inactivated form phosphorylated GSK-3 (pGSK-3) were analyzed using DNA microarray, protein array, Western hybridization, and immunohistochemical analysis. RESULTS: We found increased expression of GSK-3 in both the nasal polyps and the inferior turbinate of patients with CRSwNP compared with those with healthy mucosa (P < .01). We did not observe a difference between nasal polyps and the inferior turbinate of patients with CRSwNP, but a highly significant increase in the phosphorylation rate of GSK-3 was detected in the tissue of nasal polyps compared with the turbinates of patients with CRSwNP (P < .01). CONCLUSION: GSK-3 may play a crucial role in the inflammatory process in CRSwNP. Nasal polyps originate mainly in the mucosa of the middle meatus of the nose and rarely occur in the region of the inferior turbinate. The inhibition of GSK-3 by phosphorylation in nasal polyps, in contrast to the inferior turbinate, is a possible explanation for the different behavior of the mucosa of the middle meatus and the inferior turbinate.

Presence of hyaluronidase isoforms in nasal polyps.

BACKGROUND: Nasal polyps are benign lesions originating from the nasal mucosa or paranasal sinuses. The most important etiological factor seems to be increased hydration of epithelium and hyperplasia of the extracellular matrix, which may involve hyaluronan, a high molecular mass extracellular glycosaminoglycan. Degradation of hyaluronan proceeds through the action of specific hyaluronidases. OBJECTIVE: The aim of the present study was to investigate the hydrodynamic size of hyaluronan and the presence of the various hyaluronidase isoforms in nasal polyps. METHODS: Samples of polypoid mucosal tissue and normal nasal mucosa were obtained from twenty patients suffering from nasal polyposis. Zymographic analysis and western blotting were used to detect hyaluronidase activity. RESULTS: The results indicated the presence of hyaluronan of small molecular mass in all samples examined. About one third of it has a mean molecular mass of 240 kDa, exactly that required for the expression of inflammatory response. Laboratory analysis suggested that degradation of hyaluronan occurred through the action of three hyaluronidase isoforms: Hyal-1, Hyal-2 and PH-20. CONCLUSIONS: Since hyaluronan fragments of 200-250 kDa induce the expression of inflammatory cytokines, a specific role of hyaluronidases in the development or progression of nasal polyps may be concluded. Therefore, new treatment protocols may be proposed.

Inducible nitric oxide synthase (iNOS) in sinonasal polyp pathogenesis.

OBJECTIVES: We investigated the role of inducible nitric oxide synthase (iNOS) in the pathogenesis of sinonasal polyps. METHODS: Adult patients (21 men, 3 women) with nasal polyposis underwent functional endoscopic sinus surgery. Nine adults without polyps (6 men) who underwent septoplasty and/or rhinoplasty served as controls. Polyp specimens came from three regions: the maxillary sinus (10), ethmoid sinus (14), and nasal cavity (10). Control group samples (9) came from the inferior turbinate. Specimens were evaluated in eight mucosal layers for count and distribution of inflammatory cells and iNOS expression. An iNOS positivity index (PI) was determined for the epithelium (E), subepithelial layer of the lamina propria (SE), and deep paraglandular layer of the mucosa (D). RESULTS: Polymorphonuclear cell (PMNC) % values of the ethmoid and maxillary sinus and overall ethmoid sinus PI were significantly higher in the polyp group. Patients with longer polyp duration, D-perivascular (D-pv), and a higher Brinkmann index had decreased ethmoid sinus D PIs. However, in older patients and patients with longer polyp duration, perivascular PIs increased in maxillary sinus SE and D, respectively. Furthermore, as PMNC % and iNOS-PMNC PI increased, SE_glandular and epithelial_apical iNOS values decreased. In the ethmoid and maxillary sinuses, iNOS_D_. endothelial values increased but decreased in the nasal cavity. CONCLUSIONS: iNOS may play a role in sinonasal polyp pathogenesis, especially in mucosal SE and D layers. Increased vascular permeability, stromal edema, inflammatory cell migration into the stroma of the mucosa, and increased mucosal gland secretion may result in polyp formation.

Nox4 mediates hypoxia-stimulated myofibroblast differentiation in nasal polyp-derived fibroblasts.

BACKGROUND: Chronic hypoxia is associated with remodeling in various organs. Reactive oxygen species (ROS) derived from NADPH oxidases (Nox), and transforming growth factor-ß(1) (TGF-ß(1)) have been implicated in the pathogenesis of hypoxia-induced remodeling. The aims of this study were to determine in hypoxia-stimulated nasal polyp-derived fibroblasts (NPDF) the effect of hypoxia on the differentiation of myofibroblasts, the role of ROS, the major Nox homolog mediating myofibroblast differentiation, and the role of TGF-ß(1). METHODS: Eight primary cultures of NPDF were established from nasal polyps, which were incubated under hypoxic conditions. Reverse transcription polymerase chain reaction for αSMA, Nox1, Nox3, Nox4, Nox5, and fibronectin mRNA was performed. Western blotting for α-SMA and fibronectin was done. ROS production was detected using a fluorometer. NPDF were pretreated with ROS scavengers and transfected with siNox4. The TGF-ß(1) protein level was measured by ELISA. The effect of treatment with TGF-ß(1) type I tyrosine kinase inhibitor SB431542 on myofibroblast differentiation was observed. RESULTS: Hypoxic stimulation of NPDF significantly increased α-SMA and fibronectin mRNA and protein expression. ROS production was increased by hypoxia, and ROS scavengers inhibited myofibroblast differentiation. Nox4 mRNA was the only Nox homolog increased by hypoxia. Transfection with siNox4 inhibited myofibroblast differentiation. TGF-ß(1) was secreted endogenously by hypoxic NPDF. SB431542 significantly inhibited myofibroblast differentiation. CONCLUSIONS: Hypoxia induces myofibroblast differentiation of NPDF through a signaling pathway involving Nox4-dependent ROS generation and TGF-ß(1). Therapies targeting Nox4 may be effective against remodeling of nasal polyps.

Expression of nitric oxide synthases in leukocytes in nasal polyps.

BACKGROUND: Nitric oxide (NO) has various roles in airway physiology and pathophysiology. Monitoring exhaled NO levels is increasingly common to measure airways inflammation and inhaled NO studied for its therapeutic value in premature infants and adult respiratory distress syndrome. NO is produced by 3 isoforms of NO synthase (NOS1, 2, 3), and each can play distinct and perhaps overlapping roles in the airways. However, the distribution, regulation, and functions of NOS in various cells in the upper airways, particularly in leukocytes, are incompletely understood. OBJECTIVE: To characterize the expression of NOS isoforms in leukocytes in normal middle turbinate tissues (MT) and in inflammatory nasal tissue (nasal polyps, NP). METHODS: Normal MT tissue was collected from surgical specimens that were to be discarded. The NP samples were from surgical tissue archives of 15 patients with chronic rhinosinusitis. Isoforms of NOS in cells were identified by double immunostaining using NOS isoform-specific and leukocyte-specific (mast cell, eosinophil, macrophage, neutrophil, or T cell) antibodies. RESULTS: The proportion of total cells below the epithelium that were positive for each isoform of NOS was higher in NP than in MT. Each isoform of NOS was found in all leukocyte populations studied, and there were significant differences in the percentage of leukocytes expressing NOS isoforms between MT and NP. CONCLUSION: All isoforms of NOS are expressed in leukocytes in MT and NP, and their expression varies among leukocyte types. Our data provide a basis to investigate the regulation, cell distribution, and distinct functions of NOS isoforms in normal and inflamed nasal tissues.

[Role of the -765 G/C polymorphism of COX-2 gene in pathogenesis of chronic rhinosinusitis with nose polyps in a Polish population]. / Znaczenie polimorfizmu -765G/C genu COX-2 dla patogenezy przewleklego zapalenia zatok przynosowych z polipami nosa w populacji polskiej.

INTRODUCTION: It is believed that local factors within the nasal cavities contribute to the formation of nasal polyps. The disruption of local homeostasis mechanisms in a chronic inflammatory process is one of those factors. Cyclooxygenase (COX)-2 expression is activated in the course of the immune response to extracellular and intracellular stimuli. Also, an increase of the gene expression can be associated with the development of nasal polyps in patients with chronic sinusitis. THE AIM OF THE STUDY: The aim of this study was an evaluation of the role of the -765G/C COX-2 polymorphism in sinusitis pathogenesis in patients with nasal polyps. MATERIALS AND METHODS: The study group consisted of 100 patients, aged 35-65, with chronic sinusitis and nasal polyps and 150 people in the age, sex-, age- and ethnicity-matched control group. The study material included DNA isolated from peripheral blood lymphocytes of the patients and the controls. PCR-RFLP method was used in genotyping polymorphic variants of COX-2. RESULTS: In comparison to the control group, the group of the patients with chronic sinusitis and nasal polyps showed a statistically significant increase in the occurrence frequency of the -765G/C polymorphic variant of COX-2 gene (OR 4.04; 95% CI 2.32-7.03; p > 0.001) and C allele (OR 3.68; 95% CI 2.38-5.68; p < 0.001). CONCLUSIONS: The -765G/C genotype of COX-2 can be associated with an increased risk of the occurrence of chronic sinusitis with nasal polyps in the Polish population.

Variations in expression of matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 in nasal mucosa of aspirin-sensitive versus aspirin-tolerant patients with nasal polyposis.

BACKGROUND: Matrix metalloproteinases (MMPs) are key enzymes responsible for extracellular matrix degradation contributing to the progressive histological changes seen in lower airway disease, including asthma. MMP-9 and TIMP-1 have also shown some role in the pathogenesis of chronic rhinosinusitis (CRS) and nasal polyposis (NP). OBJECTIVE: We aim to determine variability in expression of MMP-9 and its inhibitor, tissue inhibitor of metalloproteinase-1 (TIMP-1), in sinus tissue from distinct patient populations presenting with nasal polyposis. METHODS: The expression of MMP-9 and TIMP-1 was investigated in nasal polyp tissue from 6 aspirin-sensitive (AS) and 6 aspirin-tolerant (AT) patients undergoing endoscopic sinus surgery for chronic rhinosinusitis with nasal polyposis (CRSwNP). Sinus mucosa from 6 patients with chronic rhinosinusitis without nasal polyposis (CRSsNP) was used as control. The MMP-9 and TIMP-1 expression was measured using immunofluorescence technique and graded using manual and computerized methods. RESULTS: Expression of TIMP-1 was significantly reduced in the AS group when compared with both the AT and CRSsNP (control) groups (P < .001). The MMP-9/TIMP-1 ratio was significantly increased in the AS group when compared with other patient groups (P < .001). The MMP- 9 expression was similar between study and control groups. CONCLUSION: These results support the importance of MMP-9 and TIMP-1 expression in nasal polyp formation. The decreased expression of TIMP-1 in AS patients may promote the effects of MMP-9 expression and thus contribute to tissue remodeling and inflammatory changes. This finding may lead to further understanding of disease severity and resistance to treatment in this group of patients, as well as the pathogenesis of nasal polyps.

The glutathione-S-transferase gene polymorphisms (Gstt1, Gstm1, and Gstp1) in patients with non-allergic nasal polyposis.

There is an ongoing dilemma about the pathogenesis of nasal polyp (NP). The etiology of NP is multifactorial. Reactive oxygen species and oxidative stress are also suggested to be among the possible factors in NP development. Glutathione-S-transferase (GST) is one of the important detoxifying enzymes. It is not known whether GST plays any role in NP development. We aimed to investigate the relationship between GST subgroup (GSTT1, GSTM1, and GSTP1) polymorphisms, and NP development. Seventy-five patients with NP with or without asthma (NP with asthma: 22, NP without asthma: 53) were used as a study group. As much as 167 healthy individuals were involved as the control group. NP diagnosis was made by nasal endoscopy and paranasal sinus computed tomography (CT). NP was defined as the presence of endoscopically visible bilateral polyps originated from the middle meatus to the nasal cavity and affecting more than one paranasal sinus confirmed by CT. Blood was collected in EDTA-containing tubes and DNA was extracted from the leukocytes. The genotyping of polymorphisms of GSTT1, GSTM1, and GSTP1 were done using real time polymerase chain reaction. Chi-square (chi(2)) and Fisher's (F) exact tests were used for statistical evaluation. A 2-fold increased risk of NP could be found in individuals with the GSTT1 null genotype (OR = 2.03, 95% CI = 1.03-4.011). The distribution of GSTM1 null genotypes was not significantly different between the NP patients and controls and there was also no significance between the GSTP1 genotypes and NP. In conclusion, GST gene polymorphisms may be important in pathogenesis of NP. Additional studies which include larger study groups in different geographic localizations may be more useful to evaluate association with GST polymorphism and NP.

[Cathepsin D activity in chronic rhinosinusitis with nasal polyps]. / Ocena aktywnosci katepsyny D w blonie sluzowej pacjentów z przewleklym zapaleniem zatok przynosowych z polipami.

UNLABELLED: Nasal polyposis affects about 1 to 4% of the population. Polyps develop in oedematous and inflammated mucous membrane. In spite of the intensive research the pathomechanism of their development is not fully understood. The majority of the theories concerning the development of nasal polyps emphasize the role of the inflammatory process causing the rupture of the epithelium and the basal membrane. Cathepsin D is one of important mediators of inflammatory processes, that may be involved in the pathogenesis of nasal polyposis. THE AIM OF THE STUDY: was to establish the role of the cathepsin D in the pathogenesis of nasal polyps. MATHERIAL AND METHOD: Tissues were taken from 39 patients treated with endoscopic sinus surgery due to chronic rhinosinusitis with polyps. The activity of the cathepsin D was assesed with spectrofotometric method using the specific inhibitor (pepstatin) in tissue of nasal polyps, in oedematous and the inflammated mucous membrane of the nasal conchae and the samples of mucous membrane taken from the nasal septum. RESULTS: Statistically significant difference in cathepsin D activity between polypoid tissue, inflammated mucosa and the mucous membrane of the nasal septum was detected (t-student test, p < 0.05). No difference in the activity of this enzyme was observed between the polypoid tissue and the inflammated mucosa. CONCLUSION: Increased activity of the cathepsin D in nasal polyps and inflammatory changed mucosa confirm the important role of the cathepsin D in inflammatory processes leading to damage and subsequent remodeling of mucous membrane. We believe that further research on the activity of other proteolytic enzymes is necessary to demonstrate the differences between the inflammable changed mucous membrane and nasal polyps.

[The role of infection in the development of polypous rhinosinusitis in patients with bronchial asthma].

At present, many authors accept the many-factor theory of development of polypous rhinosinusitis associated with bronchial asthma according to which this condition should be regarded as an inflammatory syndrome in subjects predisposed to a specific tissue reaction. Inflammation induced by an infection is accompanied by the release of protease-inhibiting enzymes that turn inflammation into a chronic process thereby contributing to tissue disintegration, remodeling of mucous membranes, and development of polyps.

The association of oxidative stress and nasal polyposis.

Many diseases are linked to damage from reactive oxygen species that occurs from an imbalance between reactive oxygen species and antioxidants, a condition called oxidative stress. Nasal polyposis is considered to be an inflammatory condition in nasal and paranasal sinus cavities and its aetiology is still unclear. There are very few data on epithelial changes in nasal polyposis and their relationship with free radical damage. Malondialdehyde as a major end-product of lipid peroxidation, and superoxide dismutase and nitric oxide as antioxidants play important roles in oxidative stress. In this study, the concentrations of malondialdehyde, superoxide dismutase and nitric oxide were compared in normal and nasal polyposis-affected tissue samples. Malondialdehyde levels were significantly higher, and superoxide dismutase and nitric oxide levels were significantly lower in patients with nasal polyposis compared with the control group. This study demonstrates that there is a strong relationship between oxidative stress and the pathogenesis of nasal polyposis.

[Study on the relationship between 11ß-hydroxysteroid dehydrogenase and glucocorticoid response in nasal polyps].

Objective: To investigate the expression of 11ß-hydroxysteroid dehydrogenase (11ß-HSD) in polyps of patients with chronic rhinosinusitis with nasal polyps (CRSwNP) and its correlation with glucocorticoid sensitivity. Methods: The prospective study method was applied. Forty-three adult CRSwNP patients from Otorhinolaryngology Hospital, First Affiliated Hospital of Sun Yat-sen University between April 2016 and June 2017 were enrolled in this study. There were 19 males and 24 females with the age of (37.44±7.42) years old. The endoscopic scores by nasal Polyps Grading System before and after one-week prednisone treatment (0.5 mg/(kg·d)) were evaluated. The response of glucocorticoid by the total endoscopic scores was estimated. According to the patient's reduced nasal polyp endoscopic score, patients were devided into nasal polyps insensitive to glucocorticoids treatment group (insensitive group) and nasal polyp sensitive to glucocorticoids treatment group (sensitive group). The expression of 11ß-HSD1, 11ß-HSD2 in nasal polyps were measured by Real-time PCR (RT-PCR), Western Blot and immunohistochemisty. According to the clinical data, the Logistic regression models and receiver operation characteristics (ROC) curves were used to explore the predictor for glucocorticoid response in CRSwNP. Results: The expression of 11ß-HSD1 and 11ß-HSD1/11ß-HSD2 was higher in sensitive group than that of insensitive group, while the expression of 11ß-HSD2 was lower (rank average was 26.08 vs 16.33, 27.24 vs 14.72, 18.66 vs 26.64, Z value was -2.511, 0.323, -2.059, respectively, all P<0.05). The endoscopic scores in CRSwNP group declined whereas the expression of 11ß-HSD1/11ß-HSD2 increased (r=0.528, P=0.001), while the cutoff value of the ratio of 11ß-HSD1/11ß-HSD2 was 2.290 (sensitivity was 79.17%, specificity was 88.89%). Conclusions: There is a positive correlation between the response of glucocorticoid and the ratio of 11ß-HSD1/11ß-HSD2, which could be used as a marker in predicting the level of tissue response to glucocorticoid therapy in CRSwNP.

Oxidative CaMKII as a potential target for inflammatory disease (Review).

CaMKII is a calcium­activated kinase, proved to be modulated by oxidation. Currently, the oxidative activation of CaMKII exists in several models of asthma, chronic rhinosinusitis with nasal polyps, cardiovascular disease, diabetes mellitus, acute ischemic stroke and cancer. Oxidized CaMKII (ox­CaMKII) may be important in several of these diseases. The present review examines the mechanism underlying the oxidative activation of CaMKII and summarizes the current findings associated with the function of ox­CaMKII in inflammatory diseases. Taken together, the findings of this review aim to improve current understanding of the function of ox­CaMKII and provide novel insights for future research.

Expression and distributional patterns of the inhibitor of apoptosis protein family and caspase 3 in nasal polyps.

OBJECTIVES: To investigate the expression and distributional patterns of the inhibitor of apoptosis protein (IAP) family and caspase 3 in nasal polyps and normal nasal mucosa and to evaluate the possible effects of the IAP family and caspase 3 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: Reverse transcriptase-polymerase chain reaction, immunohistochemical analysis, and Western blot analysis were performed. MAIN OUTCOME MEASURES: The expression and distribution of cIAP1, cIAP2, XIAP, survivin, and caspase 3 were evaluated in normal turbinate mucosa and nasal polyps. RESULTS: cIAP1, cIAP2, and XIAP were expressed in normal human nasal mucosa, where they were detected in submucosal glands, epithelial cells, vascular endothelial cells, and inflammatory cells. However, cIAP1 was not expressed in nasal polyps, whereas cIAP2 and XIAP were expressed in submucosal glands, epithelial cells, vascular endothelial cells, and inflammatory cells. Caspase 3 was localized to a portion of the epithelial cells in normal nasal mucosa and nasal polyps. Survivin was not expressed in any samples. Furthermore, cIAP2, XIAP, and caspase 3 did not show a significant difference in their expression levels between normal nasal mucosa and nasal polyps. CONCLUSION: The present results indicate that cIAP1, cIAP2, XIAP, and caspase 3 may regulate the homeostasis of normal nasal mucosa, whereas cIAP2, XIAP, and caspase 3 may take part in the pathogenesis of nasal polyps.