Immunocytochemical distribution of the c-H-ras protein in nasal polyps: localization to the terminal bars

Objective: This study was performed to investigate the role of proto-oncogene products, c-H-ras and c-erbB-2, in the pathophysiology of nasal polyps. Methods: An immunocytochemical investigation of the expression of proto-oncogene products of c-H-ras and c-erbB-2 was performed on 16 nasal polyps and 15 nasal mucosa specimens. Results: The c-H-ras protein was found to be localized to the terminal bars of apical cells of the epithelium in 11 of 16 nasal polyps and in seven of 15 nasal mucosa. Localized staining at the terminal bars for the c-H-ras protein was significantly more frequently observed in glandular-cystic type than in edematous type nasal polyps. Such localized staining was significantly more frequently seen in polyp specimens with invaginated epithelia than in those with no invaginated epithelium. Our findings confirmed that the c-erbB-2 protein was mainly localized to the plasma membrane in all samples. Conclusion: These results suggest that the c-H-ras protein localized to the terminal bars plays an important role in the pathophysiology of glandular-cystic type nasal polyps and that it may be related to invagination of nasal polyp epithelium.