Periostin and osteopontin are overexpressed in chronically inflamed sinuses

Abstract

In chronic rhinosinusitis (CRS), the inflammation leads to a proliferative response in the extracellular matrix (ECM). Periostin and osteopontin are 2 ECM proteins which have received attention for their roles in tissue remodeling in inflammatory diseases of the upper and lower airways. Transforming growth factor beta-1 (TGFβ1) is an inflammatory cytokine that has been implicated in fibrotic conditions affecting virtually every organ. In this study we seek to evaluate the differential expression of periostin, osteopontin, and TGFβ1 in the ethmoid sinus and nasal floor of patients with CRS. Furthermore, we seek to determine if a correlation exists between their differential expression in the nose and sinuses of patients with CRS. Biopsies from ethmoid sinus and nasal floor mucosa were taken from 15 patients undergoing functional endoscopic sinus surgery (FESS) for CRS. Complementary DNA (cDNA) microarray analysis demonstrated upregulation of periostin and osteopontin in the ethmoid sinus samples. Quantitative real-time polymerase chain reaction (RT-PCR) was performed for periostin, osteopontin, and TGFβ1. Statistical analysis was undertaken to examine correlations between the 3 genes of interest. RT-PCR confirmed that periostin and osteopontin were overexpressed in the ethmoid samples compared to the nasal floor. The differential expression of both periostin and osteopontin showed significant correlation with TGFβ1. Periostin and osteopontin appear to be involved in ECM remodeling seen in CRS. TGFβ1 may be an upstream inducer of CRS-related changes in ethmoid sinus mucosa.