Rhinovirus-Induced Mucin Gene Expression in Airway Epithelial Cells / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: It is unclear whether rhinovirus infections promote mucus secretion in airway epithelial cells. Increase of mucin gene expression and mucin production is associated with mucus hypersecretion. We therefore investigated the effect of rhinovirus infection on mucin gene expression in airway epithelial cells. MATERIALS AND METHOD: The effect of rhinovirus-16 infection on the gene expression of MUC- 5AC, MUC5B, MUC6, MUC7, and MUC8 was evaluated using semi-quantitative reverse transcription polymerase chain reaction in A549 cells. RESULTS: Rhinovirus significantly increased MUC5AC, MUC7, and MUC8 messenger ribonucleic acid (mRNA) expressions in A549 cells, but it did not significantly affect the expression of MUC5B and MUC6 mRNA. CONCLUSION: This results show that rhinovirus may induce mucus secretion in airway epithelial cells.

Increase of Rhinovirus Replication in Airway Epithelial Cells by Staphylococcal Enterotoxin A and B / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES : The toxins generated from Staphylococcus aureus, Staphylococcal enterotoxin A (SEA) and B (SEB), are reported to have an important role in the pathogenesis of chronic rhinosinusitis. As a basic step for elucidating the pathophysiologic responses of the nasal mucosa of chronic rhinosinusitis associated with rhinovirus infection, this study investigated the effect of SEA and SEB on rhinovirus infection in A549 cells. MATERIALS AND METHOD : The effect of SEA and SEB on the rhinovirus-induced changes in intercellular adhesion molecule-1 (ICAM-1) expression was assessed by flow cytometry. The effect of staphylococcal toxins on the rhinovirus-induced cytokine secretion was measured by ELISA. The effect of the replication of rhinovirus in the cells was examined by viral culture with subsequent determination of viral titer. RESULTS : ICAM-1 expression was increased in the rhinovirus infection group. Cytokine secretion was also increased in the rhinovirus infection group. But there was no additional increase due to staphylococcal toxins regarding the ICAM-1 expression and cytokine secretions. Staphylococcal toxins increased viral titer in proportion to toxin concentrations. CONCLUSION : SEA and SEB increased rhinoviral replication in airway epithelial cells. This result shows that airway epithelial cells with chronic rhinosinusitis are more favorable environments for rhinovirus infection.

Effect of Ethanol on Rhinovirus-16 Infection in A549 Cells / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Rhinovirus (RV) enters into the airway epithelial cells via the membrane bound receptor ICAM-1. The epithelial cells produce chemotactic cytokines after RV infection. The purpose of this study is to investigate the effect of ethanol on promoting RV infection in airway epithelial cells by increasing the ICAM-1 level and causing a reversible damage in epithelial barrier function. SUBJECTS AND METHOD: We pretreated various concentrations of low non-cytotoxic ethanol to A549 cells before RV infection and investigated the effect of ethanol on RV infection. The changed in epithelial barrier function was assessed by transepithelial electrical resistance as measured by voltmeter. Effect of ethanol on ICAM-1 expression was assessed by flow cytometry. Epithelial cytokine response was evaluated using ELISA technique. The level of viral replication was expressed as viral titer, which was determined through viral culture on MRC-5 cells. RESULTS: Ethanol increased ICAM-1 mean fluorescence intensity and the viral titer according to the pretreated ethanol concentrations. But increment of ICAM-1 was inconsistent with increase of viral titer and vise versa. In ethanol treated cells, the production of cytokines was increased and it was consistent with increase of viral titer. Ethanol treatment had no effect on transepithelial resistance. CONCLUSION: Ethanol pretreatment enhanced the ICAM-1 expression, viral replication and RV induced cytokine secretion in A549 cells. But we could not prove the association of RV infection with ICAM-1 expression induced by ethanol. Transepithelial resistance was not changed after ethanol treatment.

The Effect of Histamine on Rhinovirus-16 Infection in Airway Epithelial Cells / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: It is not known if allergies promote rhinovirus infections or aggravate the symptoms of common cold due to rhinoviruses. Histamine is an important immune mediator that induces symptoms of allergic rhinitis and asthma. We therefore investigated the effect of histamine on rhinovirus-16 infection in airway epithelial cells. MATERIALS AND METHOD: A549 cells were incubated for 24 hours with rhinovirus, histamine (10(-5), 10(-4), or 10(-3) M), both, or neither. Mean fluorescence intensity (MFI) of intercellular adhesion molecule-1 (ICAM-1) was estimated by flow cytometry, and secretion of IL-6 and IL-8 was measured by ELISA. Viral titers of rhinovirus-16 were measured by their cytopathic effects on lung fibroblasts after serial dilution. RESULTS: Histamine and rhinovirus acted synergistically to increase IL-8 secretion and enhance viral titer in the supernatants of cultured cells. In contrast, histamine and rhinovirus did not show synergistic effects on cell surface expression of ICAM-1 or on IL-6 secretion. CONCLUSION: Histamine may potentiate the secretion of IL-8 after rhinovirus-16 infection and may increase rhinovirus-16 titer in airway epithelial cells in a dose dependent manner.

Comparison of Rhinovirus Infection Rate and Virus-induced Cytokine Secretion between Nasal Polyp Mucosae and Normal Sphenoid Sinus Mucosae Organ Culture Model

BACKGROUND AND OBJECTIVES: Human rhinovirus (HRV) infection is the primary cause of the common cold. It was often reported that the frequency of viral rhinitis is higher among patients with chronic rhinosinusitis with nasal polyposis (CRS/ NP) than normal subjects. And, patients with nasal polyps often complain that they suffer from a relatively severe degree of URI. The purpose of this article was to evaluate whether the HRV infection rate and virus-induced cytokine secretion is different between the organ culture model of the nasal polyp mucosae and the sinus mcuosae. MATERIALS AND METHODS: Organ cultures of nasal polyps from sixteen CRS/NP patients and normal sphenoid sinus mucosae from nineteen patients who underwent the trans-sphenoidal pituitary surgery were tested. The successful viral infection by HRV-16 was determined by seminested reverse transcription-PCR. Immunoreactive IL-6 and IL-8 were quantitated using the ELISA. RESULTS: A PCR product indicating the successful RV infection was detected in nine of sixteen (56.3%) polyp samples and eleven of nineteen (57.9%) normal sphenoid sinus samples were tested positive for HRV-16. Rhinovirus infection increased the IL-6 and IL-8 secretion to 236% and 173% in polyp samples and to 231% and 145% in sphenoid mucosa samples respectively. However, there was no significant difference in rhinovirus infection rate and in the rhinovirus-induced IL-6 and IL-8 secretion between the groups. CONCLUSION: The results of this study may suggest that the nasal polyp mucosae, when compared with normal sinus mucosae, did not show more vulnerability to HRV infection nor more intense cytokine response by HRV infection.

Effect of Clarithromycin on Rhinovirus-16 Infection in A549 Cells

BACKGROUND AND OBJECTIVES: Rhinovirus enters into airway epithelial cells via the membrane bound receptor ICAM-1. Infected epithelial cells secrete the cytokines such as IL-6 and IL-8, which induce neutrophil migration into the epithelium. Clarithromycin has been found to inhibit ICAM-1 production and secretion of IL-6 and IL-8. We hypothesized that these properties of clarithromycin may be applicable in treating rhinovirus infection. MATERIALS AND METHOD: We assayed the effects of clarithromycin on rhinovirus infected A549 cells. ICAM-1 expression was assessed by flow cytometry, and cytokine secretion was assayed by ELISA. The level of viral replication was expressed as viral titer, which was determined through viral culture on MRC-5 cells. RESULTS: The mean fluorescence intensity of ICAM-1 in rhinovirus infected cells decreased from 12.4+/-0.59 to 9.2+/-0.72 after treatment with clarithromycin. The production of IL-1beta, IL-6, and IL-8 was decreased after rhinovirus infected cells were treated with clarithromycin. In the absence of rhinovirus infection, clarithromycin had no effect on ICAM-1 expression or cytokine secretion. The rhinovirus titer in infected cells was 10(3.71) TCID 50 U/ml, which was reduced following clarithromycin treatment to 10(2.14) TCID 50 U/ml. CONCLUSION: These findings suggest that clarithromycin treatment of rhinovirus infected A549 cells inhibited rhinovirus induction of increased ICAM-1 expression, cytokine elaboration, and viral replication.

The Change of Hearing Threshold by the Lactate Delivered to Round Window in Guinea Pigs / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: It is well known that hearing loss can occur by the decreased cochlear blood flow. Because lactate is known to accumulate when there is ischemia in the tissue, we designed this study to analyze the effect of lactate delivered to the inner ear on the hearing threshold measured by the auditory brainstem response (ABR). MATERIALS AND METHOD: We used 22 guinea pigs (GPs) with normal Preyer's reflex, and used 6 GPs (12 ears) to investigate the effect of lactate concentration on the change of hearing threshold and used 6 GPs (12 ears) to investigate the effect of osmolarity on the change of hearing threshold. We determined the concentration of lactate to exclude the effect of osmolarity on the change of hearing threshold. Ten GPs were divided into a control group (n=5, 10 ears) and a study group (n=5, 10 ears). The mastoid cavity was opened to expose the round, and then HBSS buffer (300 mOsm) was applied on the round window. Hearing threshold was measured by ABR after application of 10mM lactate and buffer solution as control. RESULTS: In the control group, the initial hearing threshold was 29.5 dB+/-3.6 dB (mean+/-SD) and changed to 33.5 dB+/-4.7 dB when buffer was applied to the round window. It changed to 33.0 dB+/-4.2 dB 1 hour after applying the buffer, and 37.5 dB+/-3.5 dB 4 hour later. In the study group, the initial hearing threshold was 27.0 dB+/-5.8 dB. The thresholds right after the buffer was applied to the round window, one hour and four hour later were 32.5 dB+/-4.8 dB, 48.0 dB+/-4.2 dB, and 54.5 dB+/-5.9 dB, respectively. There were significant statistical differences between the two groups with regard to the threshold after 1 hour and 4 hours (p<0.05). CONCLUSION: We could observe the elevation of hearing threshold after applying lactate on the round window of guinea pigs. Through these findings, we can draw the conclusion that lactate may be one of the factors raising the hearing threshold by tissue ischemia.

Effect and Catabolism of All-trans Retinoic Acid in Head and Neck Squamous Cell Carcinoma / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: All-trans retinoic acid (RA) is a form of vitamin A analogue that has shown chemopreventive activities in many types of malignancy with the properties that regulate cellular differentiations and suppress malignant proliferations. It is thought that the catabolism of RA is mediated by cytochrome P450RAI (CYP26) and its absorption, effects and catabolism are related to cellular retinol binding proteins (CRBP-I and II) and cellular retinoic acid binding proteins (CRABP-I and II). With eight different squamous cell carcinoma cell lines (AMC-HN-1~-8), we investigated the effects of RA and roles of these proteins in the metabolism and regulatory activity of RA. MATERIALS AND METHODS: Survival fractions of eight AMC-HN cells were analyzed six days after the treating them with 1 nM of RA. Reverse transcription-polymerase chain reactions (RT-PCR) were performed before and 24 hours after the load of 1 nM of RA to detect the expressions of CRBP-I, CRABP-I, CRABP-II, and CYP26. RESULTS: Resistances to RA were detected in AMC-HN-1, -2, -5, and -6 cell lines after RA treatment, and AMC-HN-3, -4, -7, and -8 cell lines showed sensitive responses to RA. Before the addition of RA, expressions of CYP26 were detected in AMC-HN-1, -2, -4, -5, -6, and -7 cell lines and CRBP-I was expressed in AMC-HN-3, 4, 5, 7, and -8. After RA addition, the expressions of CYP26 were enhanced in AMC-HN-2, -5, -6, and -7. In six of eight cell lines, CRABP-I was suppressed and CRABP-II was enhanced after RA treatment. CONCLUSION: These results suggest that CYP26 has a direct correlation with the cellular metabolism of RA in the head and neck squamous cell carcinomas and that CRABP-I and CRABP-II have distinct roles in the regulatory effects of RA. CRBP-I might be an indicator that implies the responsiveness to RA.

GEnetic Change in Transforming Growth Factor-B (TGF-B) Receptor Type I and Type II Genes with Resistance to TGF-B of Human Breast Cancer Cells / 대한암학회지

PURPOSE: Transforming growth factor-Bs (TGF-Bs) are prototypic multifunctional negative growth factors that inhibit the growth of many cell types. TGF-B type I and II receptors(RI, RII) are transmembrane receptors containing cytoplasmic serine/ threonine kinase domain and have been implicated in mediating TGF-B activity. Because a heteromeric complex of RI and RII is required for TGF-B signal transduction, cancer cells may reduce the expression of either RI or RII to escape from growth inhibition of TGF-B. We examined the correlation between the growth inhibitory activity of TGF-B1 and the genetic expression of RI &RII genes in human breast cancer cell lines. MATERIALS AND METHODS: We examined the growth inhibitory activity of TGF-B1 in 5 breast cancer cell lines by incorporation of [3H] thymidine. To investigate the correlation between TGF-B1 insensitivity and genetic change of TGF-B receptor genes (RI, RII), Southem blot analysis, Northern blot analysis, and Western blot analysis were performed. We also examined whether microsatellite instability(RER) was associated with RII mutation. RESULTS: We found that 3 breast cancer cell lines (MCF-7, YCC-B101, YCC-B151) were resistant to growth inhibitory effect of TGF-B1. MCF-7 cell line expressed no detectable RII mRNA and RII protein, but showed normal structure of RII gene and normal expression of RI gene. And we did not find any abnormal expression of mRNA, protein, and genetic structure of RI &RII in YCC-B101 and YCC-B151. CONCLUSION: Our results suggest that aquired resistance to the growth inhibitory effect of TGF-B1> could be transcription regulation system of RII in MCF-7 cell line, and could be postreceptor signal transduction pathway in YCC-B101 and YCC-B151 cell lines.

Plasma TGF-beta1 as a Tumor Marker in Breast Cancer Patients / 대한암학회지

PURPOSE: Transforming Growth Factor-beta1(TGF-beta1) is the most potent inhibitor of the progression of normal mammary epithelial cells through the cell cycle. However, advanced breast cancers are mostly refractory to TGF-beta mediated growth inhibition and produce large amounts of TGF-beta, which may enhance tumor cell invasion and metastasis by its effects on extracellular matrix. Yet, little is known about the association of TGF-beta1 with progression of malignant disease in vivo. In this study, we evaluated the preoperative and postoperative plama level of TGF- in breast cancer and analyzed the utility of plasma TGF-beta1 as possible tumor marker. MATERIALS AND METHODS: ELISA(enzyme-linked immunosorbent assay) was used to measure plasma TGF-beta1 level in 45 newly diagnosed breast cancer patients and in 15 normal healthy people, and the results were compared with clinicopathologic characteristics. RESULTS: The mean plasma TGF-beta1 levels were 1.73+/-0.47 ng/ml in normal people and 5.05+/-1.41 ng/ml in breast cancer patiens. In 37 operated patients, the preoperative plasma TGF-beta1 level was 6.34+/-1.34 ng/ml and decreased to 4.48+/-1.07 ng/ml in patients with follow-up after surgery and 4.74+/-0.79 ng/ml in patients with chemotherapy. However, there was no significant correlation between plasma TGF-beta1 level and known prognostic factors including tumor size, LN involvement, tumor grade, hormone receptor status, and pathology. CONCLUSION: These findings suggest that the plasma TGF-g level can be a tumor marker in breast cancer patients and the association with progression of breast cancer will be explored in future studies.

Clinical Significance of Urokinase-type Plasminogen Activator (uPA) Expression from Serum and Tissue of Gastric Cancer Patients / 대한암학회지

PURPOSE: We measured the gastric cancer tissue uPA and plasminogen activator inhibitor-1 (PAI-1) levels and compared them to those of the peripheral and portal blood levels to evaluate the correlation. MATERIALS AND METHODS: Tissue uPA and PAI-1 levels were measured by ELISA assay (Monozyme, Netherland) in paired 85 normal and cancer tissues resected from gastric cancer patients. In 50 patients, blood uPA and PAI-1 levels were measured from pre- operative peripheral and portal blood, post-operative portal blood. RESULTS: Gastric cancer tissue uPA and PAI-1 levels increased from the early stage. The elevated cancer-to-normal ratios of the uPA and PAI-1 were constant from stage I to IV. There were correlations of uPA between normal and cancer tissues (r2=0.38) and between peripheral and pre-resection portal blood level (r2=0.64). There were no correlations between tissue PAI-1 level and blood PAI-1 levels. However, there were correlations in PAI- 1/uPA ratio between cancer tissue and peripheral blood (r2=0.25), peripheral blood and pre- resection portal blood (r2=0.60). CONCLUSION: Even if the cancer tissue levels of uPA and PAI-1 increased from the early stage of gastric cancer, only blood uPA level correlated with tissue uPA level. A modest correlation found in PAI-1/uPA ratio between cancer tissue and blood suggests applicability of blood PAI-1/uPA ratio in predicting tissue uPA, PAI-1 expression.