Expression of Cyclins (D1, A, E, and B1) in N-butyl-N-(4-hydroxybutyl)nitrosamine-induced Rat Bladder Carcinogenesis

BACKGROUND: Cell cycle deregulation plays a major role in chemical multistage carcinogenesis.Therefore, the evaluation of cell cycle proteins is important. METHODS: In order to induce carcinogenesis in the rat urinary bladder, 0.05% N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN)was administered to male Sprague-Dawley rats for 30 weeks. Expressions of cyclin D1, A, E, and B1 were examined by immunohistochemical stainings. RESULTS: Urothelial cell hyperplasia appeared at 5 weeks, followed by papilloma at 10 weeks. Superficial carcinoma was observed at 20 weeks, and invasive carcinoma developed in 40% (4/10) of the rats at 30 weeks. Expressions of cyclin D1 and A increased sequentially from normal mucosa throughhyperplasia, papilloma, and carcinoma (p<0.01). Expressions of cyclin D1, B1 and cyclin Ewere higher in invasive carcinomas than in superficial carcinomas (p<0.01). In contrast, therewas no significant difference in the expression of cyclin B1 between hyperplasia, papillomaand superficial carcinoma. CONCLUSIONS: The present results indicate the important roles of cyclin D1 and A in the development of BBN-induced urothelial carcinoma of rats. Aberrantexpression of cyclin B1 and E may contribute to the progression from superficial to invasivebladder cancer rather than tumorigenesis.

The Effects of Retinoids on Expression of beta4 Integrin and Growth of the Head and Neck Squamous Cell Carcinoma Cell Lines / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Retinoids have been used in chemoprevention trials for a variety of epithelial malignancies. However, high incidence of toxicity and drug resistance remains as problems. Increase of the retinoid metabolism by cytochrome P450 has been known as one of the several mechanisms explaining these toxicity and the aquired resistance. There have been many studies about the biological effects of retinoids in head and neck squamous cell carcinoma (HNSCC), but there is no information about the effects of the retinoids metabolism on cell biology. The study presented here is designed to examine the relationship between cytochrome P450 induction and responses to retinoids in the HNSCC cell lines. MATERIAL AND METHODS: We used a human HNSCC cell lines (AMC-HN-4, AMC-HN-6). The change of metabolic activity was analyzed using thin layer chromatography (TLC). The effects of retinoids on cell proliferation were evaluated with CellTiter 96 TMAQueous Cell Proliferation Assay. The effects of retinoids on beta4 integrin expression were evaluated with flow cytometry. RESULTS: The inhibitory effects of retinoids on cell proliferation were higher in AMC-HN-4 cell line (cytochrome P450 uninducible) than in AMC-HN-6 cell line (cytochrome P450 inducible) (p<0.05). The expression of beta4 integrin was more effectively suppressed in the AMC-HN-4 cell line than in the AMC-HN-6 cell line. CONCLUSION: The results of this study suggest that cytochrome P450 inducilbility may be an important factor to determine the biological effects of retinoids in HNSCC cells.

Acoustical Effects of Short-Term Endotracheal Intubation / 대한이비인후과학회지

Background and Objective: Patients often complain of transient hoarseness and dysphagia after undergoing procedures requiring endotracheal intubation. Transient voice changes associated with endotracheal intubation are generally assumed to be a result of vocal fold trauma. This study was designed to characterise vocal changes aftershort-term endotracheal anesthesia using acoustic analysis for monitoring the presence of and recovery from intubation trauma. MATERIAL AND METHODS: Vocal functions of 25 patients undergoing chronic ear surgeries using general anesthesia with endotracheal intubation were analyzed preoperatively and postoperatively. Fundamental frequency, jitter, shimmer, noise to harmonic ratio were measured to assess vocal function. RESULTS: In male, fundamental frequency, jitter, shimmer, noise toharmonic ratio did not differ significantly across recording sessions, although certain predictable trends were apparent. In female, statistically significant decrement in fundamental frequency and increment in jitter and shimmer were found postoperatively (p<0.05). One day after extubation, these change were return to preoperative values. CONCLUSION: Even short-term endotracheal intubation affects acoustic-characteristics of voice and acoustic analysis are sensitive to identify and monitor minor laryngeal trauma due to endotracheal intubation.

Adult-onset Otitis Media with Effusion / 대한이비인후과학회지

Otitis media with effusion(OME) is a very common disease of young children, but adult-on-set otitis media with effusion is rarely considered. A few of factors contribute to pathogenesis of otitis media with effusion, which are poor tubal dysfunction, upper respiratory viral infection, bacterial adherence, and immune status of the host. Otologic complaints are dominant in many of adult-onset OME patients. Sinusitis is the most common causal disease of adult-onset OME in our study. In our study, we conclude that adult-onset OME is a relatively common disease in contrast to the current thought and that we must carefully evaluate upper airway, especially sinuses and nasopharynx, and systemic aspects in adult-onset OME.