Comparison of Expression of Cytokeratin 7 on Epithelium of Nasal Polyps and Mucosa of Chronic Rhinosinusitis

Background and Objective: Nasal polyp is the most common benign mass of the nasal cavity and it is originated from nasal cavity or sinuses. Cytokeratins (CK) are intermediate filament proteins that provide mechanical support in epithelial cells. The purpose of this study was to compare the expression of cytokeratin 7 in epithelium of nasal polyps and nasal mucosa in chronic rhinosinusitis. Materials and Methods: This research was a cross-sectional descriptive-analytic study. Level of expression of cytokeratin 7 in 90 samples from patients with nasal polyps and 30 samples from patient with chronic rhinosinusitis in Mostafa Khomaini hospital (Tehran, Iran) during 2007-2011 was assessed by immunohistochemistry using monoclonal antibody and Hematoxilin-Eosin staining and the results were analyzed by Mann-Whitney and t-tests. Results: There was significant correlation between the level of expression of cytokeratin 7 in the epithelium of nasal polyps and nasal mucosa in chronic rhnosinusitis (P < 0.05). In other words, the level of expression of cytokeratin 7 in the epithelium of nasal polyp was higher than in nasal mucosa in chronic rhinosinusitis. There was also no correlation between the levels expression of CK7 in nasal polyp and other variable such as age and sex. Conclusion: According to the significant correlation for the expression levels of CK7, it seems that this biologic factor is involved in the development of nasal polyp in the presence of inflammation.