Comparative assessment of cell proliferation and accumulation of extracellular matrix in nasal polyps

In nasal polyps constantly associated with chronic inflammation, a dysregul ation of epithelial cell proliferation has been described. Involvement of e xtracellular matrix accumulation is also suggested in the formation and gro wth of nasal polyps. In this study, we attempted to evaluate the activity o f the proliferation of epithelial cells and fibroblasts and the relation be tween fibronectin accumulation and these cell proliferations in nasal polyp s. The pathological specimens of 30 patients were examined which manifested proliferating cell nuclear antigen (PCNA) expression in epithelial cells a nd Fibroblasts and in fibronectin expression. PCNA expression was quantifie d by calculating the index for each sample. No significant difference in PC NA index was found between epithelial cells and fibroblasts. However, a sig nificant correlation was found between the epithelial and fibroblastic PCNA index. In addition, fibronectin immunopositivity was well correlated with the activity of proliferation of fibroblasts. Therefore, proliferation of f ibroblasts is also an important factor in the growth of nasal polyps, and i ts relationship with fibronectin accumulation may play a role in the pathog enesis of nasal polyposis.