Inflammation-induced miR-802 promotes cell proliferation in cholesteatoma.

Cholesteatoma is a destructive and abnormal skin growth consisting of keratinizing squamous epithelium in the middle ear. Its molecular mechanisms remain poorly understood. Here, we found that the NF-κB inflammatory signaling pathway was highly activated in cholesteatoma. NF-κB activation increased the expression of microRNA-802 (miR-802) and chromatin immunoprecipitation assays showed that P65 could uniquely bind to miR-802 promoter. miR-802 overexpression promoted keratinocyte cell proliferation and cell cycle progression, while inhibition of miR-802 decreased these effects. From computational analysis and luciferase report assays, miR-802 directly repressed PTEN expression by targeting its 3'-UTR. Our results demonstrate that the NF-κb/miR-802/PTEN signaling pathway plays an important role in the development of cholesteatoma.