Reliability of airway obstruction analyses from Sleep MRI sequences.

OBJECTIVE: A real-time MRI "movie" during natural sleep ("Sleep MRI") allows observation of dynamic airway obstructions in obstructive sleep apnea syndrome (OSAS) patients. The purpose of this article was to determine the reliability of assessing these obstructions. STUDY DESIGN: Cross-sectional diagnostic test evaluation. SETTING: Academic referral center. SUBJECTS AND METHODS: A total of 23 Sleep MRI sequences randomly selected from 20 consecutive OSAS patients were analyzed by two experienced sleep surgeons on two separate occasions separated by at least two weeks. Five dimensions were assessed: presence or absence of any obstruction, presence or absence of a retropalatal obstruction, presence or absence of a retroglossal obstruction, presence or absence of a swallow, and duration of an obstructive event. RESULTS: For all dimensions measured, intra-rater reliability coefficients ranged from a low of 0.95 to a high of 1.0 for each rater. Inter-rater reliability coefficients ranged from a low of 0.85 to a high of 1.0. On two separate evaluations separated by at least two weeks, rater 1 identified a retropalatal obstruction in 100 percent of sequences, whereas rater 2 did so in 91 percent and 96 percent of the sequences, respectively. Retroglossal obstruction was identified in 57 percent (rater 1) and 65 percent (rater 2) of sequences. CONCLUSION: Intra-rater and inter-rater reliability coefficients are very high for determination of presence or absence of any obstruction, presence or absence of a retropalatal obstruction, presence or absence of a retroglossal obstruction, presence or absence of a swallow, and duration of obstruction from Sleep MRI sequences in OSAS patients.

Influence of interleukin-13 on beta-catenin levels in eosinophilic chronic rhinosinusitis cell culture.

Chronic rhinosinusitis (CRS) is one of the most common chronic diseases. The etiology and classification of CRS, with and without nasal polyps, remain unclear. Eosinophils and their products are important in the pathophysiology of allergic diseases and in host immunity to certain organisms. Interleukin 13 (IL-13) plays a pivotal role in eosinophilic inflammation. The migration of epithelial cells requires permanent re-establishment of the intercellular connection. Intercellular connections are maintained by the modulation of adherens junctions consisting of an E-cadherin/beta-catenin complex. In our study we examined the eosinophilic and non-eosinophilic paranasal mucosa obtained from two patients undergoing functional endoscopic sinus surgery. Cell cultures were incubated with human recombinant IL-13 for up to 72 h and beta-catenin concentration was determined with ELISA techniques. Furthermore, immunostaining for beta-catenin was used for the semi-quantitative description of specimens. We were able to ascertain a significant increase in beta-catenin expression in the eosinophilic paranasal cell culture after IL-13 administration compared to the non-eosinophilic culture. Immunostaining for beta-catenin was restricted to the membrane of the cells. Concerning the increased mural expression of beta-catenin, we presume that a fibrotic reaction similar to asthma and chronic obstructive pulmonary disease occurs in patients suffering from CRS. Furthermore, beta-catenin overexpression might be responsible for mucosal thickening and IL-13 seems to be an important marker in eosinophilic CRS.

Undifferentiated pleomorphic sarcoma of the parotid gland: a rare pediatric case.

BACKGROUND: Undifferentiated pleomorphic sarcoma, or malignant fibrous histiocytoma (MFH) of the head and neck is an uncommon malignancy that is exceedingly rare in the pediatric population. Although MFH was once considered the most common soft tissue sarcoma in adults, recently authors have questioned its existence as a distinct pathologic entity. METHODS: In light of this debate, we present a case of MFH with giant cells involving the parotid gland, and we review its pathology. RESULTS: We describe a 6-year-old male with parotid gland MFH. Diagnosis was fraught with difficulty, typical of this disease. He was treated with a combination of chemotherapy and radiation therapy with a good initial response. CONCLUSION: The classification of MFH has been recently debated. Nevertheless, our case is the second report of pediatric MFH involving the parotid gland. Surgical resection is the preferred treatment, but combined chemoradiation may be necessary in the head and neck region.

Chemopreventive alteration of the cell-cell adhesion in head and neck squamous cell cancer.

Approximately 310,000 new cases of oral and pharynx cancer account for a major cause of neoplasm related morbidity and mortality world-wide. Unfortunately, the survival rate has not improved significantly in the last decade. The vast majority of head and neck cancer is squamous cell carcinoma. The major adhesion-proteins involved in the development and maintenance of all solid tissue are the Cadherins. Cadherins are the transmembrane components of the adherent junction with interaction with plakoglobin and beta-catenin. Downregulation of Cadherins and catenins is frequently observed in many types of human cancer. Sulindac sulfone is one of the new therapeutic apoptotic agents that show promise in the treatment of cancer. In this study, we incubated sulindac sulfone with a head and neck cancer cell line and investigated the outcome of E-Cadherin. Immunohistochemical and Western blot analyses were then performed, with different concentrations of sulindac sulfone (100, 200, 400, 600, and 800 microMol) for 48 h. At 400 microMol of sulindac sulfone a decrease of 21% was observed; at 600 microMol, 44% decrease of beta-catenin concentration was seen, and incubation with 800 microMol resulted in 73% reduction of secreted beta-catenin. Incubation with sulindac sulfone seemed to stop proliferation; however, with respect to the controls, there was no increased reduction of the total protein. Sulindac sulfone resulted in an increase of E-Cadherin content in the head and neck squamous cell cancer cell line after 48 h of incubation; however, the reactivity was restricted to the adherent junctions. At increasing concentrations of sulindac sulfone, intercellular E-Cadherin immunostaining intensifyied. ELISA also depicted significant rising levels of E-Cadherin. Sulindac sulfone contributes to the inactivation of cGMP phospho-diesterase. Thus, the accumulation of cellular cGMP and protein kinase G is induced. The following degradation of the phosphorylated beta-catenin and the dissociation from the Cadherin-catenin complex releases E-Cadherin. This may also contribute to growth inhibition and co-ordinate with apoptosis induction. It is not really clear as to, which pathway results in the elevation of the E-Cadherin proteins. However, in epithelial cancer cells, the Cadherin-catenin complex serves as a target for the chemopreventive agent, sulindac sulfone.

Effect of vascular endothelial growth factor on fibroblasts from external auditory canal cholesteatoma.

BACKGROUND: EACC is a disease of the external auditory canal resulting in destruction of adjacent tissue. However, the role of the surrounding mesenchymal fibroblasts of the perimatrix still remains unclear. In this study we treat isolated fibroblasts of EACC with VEGF and determine FGF-2 levels. We also treat the fibroblast cultures with FGF-2 and measured VEGF levels. METHODS: All EACC cell cultures were obtained from five patients undergoing surgery and used at passage 3. After 1-4 days incubation with 50 ng/mL FGF-2, and 1-8 days incubation with 50 pg/mL VEGF incubation, the expression of the FGF-2 and VEGF protein in the supernatants of the HGF/SF-treated and -untreated culture cell lines was analyzed, respectively. RESULTS: After 8 days of incubation with 50 ng/mL VEGF, the levels of FGF-2 decreased. However, after 4 days of incubation with FGF-2 the VEGF levels increased significantly in treated tissue culture (p <0.05) in comparison to untreated EACC fibroblasts. The total protein concentration showed no significant difference in both cultures (p >0.05). CONCLUSIONS: In summary, exogenous FGF-2 increased fibroblast expression of VEGF, which is a major autocrine mediator of FGF-2-induced angiogenesis and proliferation. However, incubation with VEGF resulted in decrease of FGF-2 levels. Regarding the slow growth of the fibroblasts, they may not be as likely to exhibit a reactive or invasive phenotype as seen in middle ear cholesteatoma fibroblasts.

Influence of hepatocyte growth factor/scatter factor (HGF/SF) on fibroblast growth factor-2 (FGF-2) levels in external auditory canal cholesteatoma (EACC) cell culture.

BACKGROUND: In previous studies, we cited circulatory disorders and hypoxia as etiological factors for the formation of external auditory canal cholesteatoma (EACC) resulting in angiogenesis. Here, we investigate how the angiogenic factor hepatocyte growth factor/scatter factor (HGF/SF) influences the level of another angiogenic factor FGF-2. MATERIALS AND METHODS: After 16 to 72 hours of incubation with 20 ng/ml HGF/SF, levels of VEGF in the HGF/SF-treated and untreated culture was analyzed. We also investigated the influence of HGF/SF (20-80 ng/ml) on the concentration of FGF-2. RESULTS: After 16 hours of incubation with HGF/SF at 20 ng/ml, FGF-2 was measured at 44.19 pg/ml (control: 42.24 pg/ml). After 72 hours, FGF-2 was at 23.41 pg/ml (control: 14.83 pg/ml). After 24 hours, 40 ng/ml HGF/SF showed the highest concentration of FGF-2. CONCLUSION: FGF-2 levels were initially elevated after treatment with HGF/SF, however, further incubation did not show any increase. We assume that HGF/SF released FGF-2 in the matrix but did not induce FGF-2 expression. The most effective HGF/SF concentration was 40 ng/ml.

Targeting TGF-beta1 increases hepatocyte growth factor (HGF/SF) levels in external auditory canal cholesteatoma (EACC) epithelial cell culture.

OBJECTIVE: The transforming growth factor (TGF)-beta 1 is known to have pro- and anti-angiogenic actions. Hepatocyte growth factor/scatter factor (HGF/SF) antagonizes TGF-beta1 by stabilizing SMAD transcriptional co-repressor TGIF. HGF/SF is a multifunctional polypeptide with morphogenic, motogenic, angiogenic, and proliferative capabilities. We assume HGF to be a pivotal factor during the pathogenesis of the external auditory canal cholesteatoma (EACC). In this study, we investigate the effect of antisense targeting TGF-beta1 on HGF/SF levels in the epithelial EACC-culture. MATERIALS: For 48 h, epithelial EACC cell culture was incubated with 3 and 6 mumol antisense targeting TGF-beta1, respectively. Levels of HGF/SF were determined and normalized to cellular protein. Untreated EACC cell culture and scrambled TGF-beta1-antisense served as control. In the second experiment, EACC cells were incubated with rh TGF-beta1 (2 and 4 ng/ml) for 48 h and HGF/SF was determined. RESULTS: After incubation with 3 mumol TGF-beta1-antisense, the average level of HGF/SF was measured at 43.68 pg/ml. Incubation with 6 micromol TGF-beta1-antisense showed 64.95 pg/ml. In untreated EACC (control), the average level of HGF/SF after 48 was 34.55 pg/ml. Incubation with scrambled TGF-beta1 oligonucleotide showed an average HGF/SF level of 34.41 (3 micromol) and 35.66 (6 micromol), respectively. The difference between the scrambled antisense and the targeting antisense TGF-beta1 was significant (p<0.05). After incubation with 2 ng/ml TGF-beta1, the HGF/SF levels were at 22.16 pg/ml. TGF-beta1, 4 ng/ml, resulted in 15.33 pg/ml of HGF/SF. The difference of the levels of HGF/SF after incubation with exogenous TGF-beta1 was significant (p<0.05). CONCLUSION: In this study, levels of HGF/SF increased in the epithelial EACC cell culture after incubation with 3 and 6 mumol antisense TGF-beta1 oligonucleotides depending on the concentration of the antisense. In reverse, TGF-beta1 acted as inhibiting cytokine on HGF/SF levels. In conclusion, TGF-beta1 may be a useful therapeutic agent for managing EACC.

Up-regulation of beta-catenin in external auditory canal cholesteatoma.

The external auditory canal cholesteatoma (EACC) is a rare disease with hyperproliferation and destructive growth in the adjacent structures. Down-regulation of beta-catenin (key component of the zonula adherens) is a pivotal factor for loose tissue integrity and invasiveness. Transforming growth factor beta1 (TGF-beta1) was reported to decrease beta-catenin in mammary epithelium. We investigated the abrogation of TGF-beta1 and beta-catenin expression in EACC culture cells. Cultured EACC-specimens were incubated with 6 micromol TGF-beta1 antisense. After 48 h, expression of beta-catenin was determined by means of immunohistochemistry. The cells showed an increased mural reactivity to beta-catenin, and intracellular reactivity was unchanged. The untreated cells showed a loss of beta-catenin expression at the membranes. The predominant membranous location after treatment with TGF-beta1 antisense suggests increased tendency of the cells for tissue formation and strong cell-cell adhesion rather than migratory and invasive character, and thus TGF-beta1 antisense application is a useful therapeutical strategy.