The Effect of All-Trans Retinoic Acid on Culture of Aural Cholesteatoma Keratinocytes / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Retinoids have recently become an interest to clinicians because of their ability to inhibit migration and proliferation of the premalignant squamous cells, while enhancing growth and proliferation of normal cells. Aural cholesteatoma is defined as the state of hyperproliferative keratinocytes in the middle ear cavity. An in vitro investigation was undertaken to determine whether all-trans retinoic acid (t-RA) exhibits an inhibitory effect on cholesteatoma cell proliferation. METHODS: Cholesteatoma tissue was obtained during a middle ear operation, and the explant was cultured on six well-plates in a culture medium of Medium M-154 (Cascade Biologics Inc., USA) for one week. T-RA was then treated with 10M, 10M, 10M, 10M concentrations, respectively. The cholesteatoma explant cultures were observed daily, and topographic maps were constructed weekly to quantify the proliferation area. The explant culture area was estimated by Multiscan. RESULTS: In the absence of t-RA, the cholesteatoma explant culture area reached 401.5mm in four weeks. But with the administration of t-RA, the cultured area decreased proportionally to t-RA concentrations which reduced to 224.0 mm, 94.4 mm respectively in four weeks with 10M, 10M concentration of t-RA (p<0.05). CONCLUSIONS: This investigation showed that t-RA has a significant inhibitory effect on cholesteatoma proliferation. These results suggest that retionoids may have a role in controlling cholesteatoma disease.

Expression of Vascular Endothelial Growth Factor and Platelet-Derived Endothelial Cell Growth Factor in Head and Neck Squamous Cell Carcinoma and It's Relation to Angiogensis / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Tumor angiogenesis is an essential process required for growth and metastasis in cancer. Vascular endothelial growth Factor (VEGF) and platelet-derived endothelial cell growth factor (PD-ECGF) are known to be angiogenetic factors. The objectives of this study were to measure the expression of VEGF, PD-ECGF and microvessel density (MVD) in head and neck squamous cell carcinoma (HNSCC) and compare them to normal larynx. We also evaluated relationships of VEGF, PD-ECGF and MVD to clinicopathologic findings in HNSCC. MATERIAL AND METHODS: The expression of VEGF, PD-ECGF and MVD were evaluated by immunohistochemical staining of 26 cases of HNSCC and 6 cases of normal larynx. RESULTS: The expressions of VEGF, PD-ECGF and MVD in HNSCC were significantly higher than in the normal control (p<0.05). MVD were significantly correlated with VEGF and PD-ECGF expressions in HNSCC (p<0.05). The VEGF, PD-ECGF expression and MVD correlated with many clinicopathologic findings in HNSCC. CONCLUSION: These results suggest that VEGF and PD-ECGF are involved in angiogenesis and are related to clinicopathologic findings of HNSCC. Furthermore, we propose that expressions of VEGF, PD-ECGF and MVD to be investigated more in the future as prognostic indicators of HNSCC.

Allergic Rhinitis to Japanese Cedar in Cheju Island / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Abundance of Japanese cedars (JC) in Cheju Island has caused some of the island's residents to suffer from severe allergic symptom in the spring time. This study was carried out to verify the presence of JC allergic rhinitis (AR) in the island. Materials and Method: We performed a history survey, skin testing and nasal provocation test to JC and other common allergens for 170 residents who have symptom of AR. We also performed the same tests in 18 Japanese who had history of AR to JC and have lived in Korea more than 3 years. And as a control, skin tests were performed for 581 patients who live in Seoul. RESULTS: Positive reactions to JC were seen in 22.4% of the resident group. The prevalence rate was remarkable in the state capital of Cheju. These reactions were associated with conjunctivitis, dermatitis, asthma and food allergy. All the 18 Japanese patients were sensitive to JC. However, the allergic symptoms disappeared within 1 year after the move to Korea. And there were no patients sensitive to JC in the control subjects. Conclusions: We confirmed the presence of AR of JC in Cheju island. The distribution is comparatively coincided with JC and/or air pollution and this result indicate that environmental factors can be involved in the manifestation of the disease.

Expression of Protein Kinase C on Allergic Nasal Mucosa

Protein Kinase C (PKC) relays information in the form of a various extracellar signals across the membrane and is known to play an important role in the production of B lymphocytes and T lymphocytes, in the antigen-presentation of Langerhans cell, and in inflammatory reactions. The presentation of allergens to T lymphocytes is likely an important aspect in the pathophysiological mechanism of allergic rhinitis. Although several theories have been formulated in allergic rhinitis, signal transduction of this disease remains unknown. In this study, we focused on the role of the enzyme PKC in the allergic mucosa of the nose. Specifically, we investigated the role and the distribution of PKC isozymes in the mucous membrane of the nose. We obtained nasal mucous membrane specimens from 10 patients with house dust mite allergy and 10 patients with normal nasal mucous membrane. We performed an immunohistochemical study, an RT-PCR, and a densitometric measurement. PKCalpha, PKCbeta, and PKCzeta proteins were detected in the subepithelial layer of the allergic mucosa. However there were no detectable reactions in the nonallergic mucosa. In the RT-PCR for PKCalpha, PKCbeta and PKCzeta, there was no difference between the allergic and nonallergic nasal mucous membrane in terms of m-RNA expression. It is possible that the signal transduction pathway of PKC and over-expression of PKC protein at the post-transcription level contribute to the development of allergic inflammation in allergic nasal mucosa.