Circulating levels of Bcl-2 and its expression in the nasal mucosa of patients with chronic rhinosinusitis

Aim: To evaluate expression of anti-apoptotic Bcl-2 protein in the nasal tissue and its levels in blood serum of patients with chronic rhinosinusitis with (CRSwNP) and without nasal polyps (CRSsNP).
Material and methods: Expression of Bcl-2 in the sinonasal tissue and its levels in blood serum of patients with CRSsNP and CRSwNP were evaluated immunohistochemically and using ELISA, respectively.
Results: In patients with CRSsNP, Bcl-2 was overexpressed in nasal epithelial cells mainly in the atrophic regions. However, its upregulation was also observed in regions with epithelial cell proliferation. Immunostaining for Bcl-2 was stronger both in the stroma and epithelial lining compared with control subjects. The level of Bcl-2 in blood serum was elevated in both forms of chronic rhinosinusitis with a more pronounced increase in CRSwNP.
Conclusion: CRSsNP and especially CRSwNP are associated with overexpression of anti-apoptotic Bcl-2 in nasal epithelial and cells in the lamina propria against the background of elevated circulating concentrations of Bcl-2.