uPA affects the CRSsNP nasal mucosa epithelium apoptosis by regulating WIF1

Chronic rhinosinusitis without nasal polyps (CRSsNP) is the main type of Chronic rhinosinusitis (CRS) and is a common otorhinolaryngologic disease worldwide. However, the mechanisms of CRSsNP remain poorly understood. In this study, C57BL/6J wild-type and urokinase-type plasminogen activator (uPA) gene knockout (uPA^-/-) mice were used to construct the CRSsNP model. Primary human nasal epithelial cells (HNEC) were isolated from CRSsNP patient and treated with uPA knockdown/overexpression lentivirus. CCK-8 and Annexin-V/PI staining were used to detected cell proliferation and apoptosis. In vivo, we found that uPA depletion alleviated mucosal inflammation in the CRSsNP mice model. Wnt inhibitory factor 1 (WIF1) was upregulated in the uPA^-/- CRSsNP mice model. In vitro, inhibition of uPA increased cell proliferation and decreased cell apoptosis. Mechanistically, uPA depletion upregulated WIF1 and BCL2 expression, and reduced the expression level of BAX in CRSsNP HNEC. In contrast, decreased cell proliferation and increased cell apoptosis were observed after uPA overexpression. Consistently, a reduction in WIF1 and BCL2 expression levels and an increase in the BAX expression level were observed upon uPA ectopic expression. Furthermore, WIF1 overexpression rescued the effects caused by uPA overexpression in vitro. In conclusion, uPA affects the CRSsNP nasal mucosal epithelium cell apoptosis by upregulating WIF1. To our knowledge, this is the first study to explore the role of uPA in CRSsNP to date.