Upregulation of miR-941 in Circulating CD14+ Monocytes Enhances Osteoclast Activation via WNT16 Inhibition in Patients with Psoriatic Arthritis

Psoriatic arthritis (PsA) is a destructive joint disease mediated by osteoclasts. MicroRNAs (miRNAs) regulate several important pathways in osteoclastogenesis. We profiled the expression of miRNAs in CD14+ monocytes from PsA patients and investigated how candidate microRNAs regulate the pathophysiology in osteoclastogenesis. The RNA from circulatory CD14+ monocytes was isolated from PsA patients, psoriasis patients without arthritis (PsO), and healthy controls (HCs). The miRNAs were initially profiled by next-generation sequencing (NGS). The candidate miRNAs revealed by NGS were validated by PCR in 40 PsA patients, 40 PsO patients, and 40 HCs. The osteoclast differentiation and its functional resorption activity were measured with or without RNA interference against the candidate miRNA. The microRNA-941 was selectively upregulated in CD14+ monocytes from PsA patients. Osteoclast development and resorption ability were increased in CD14+ monocytes from PsA patients. Inhibition of miR-941 abrogated the osteoclast development and function while increased the expression of WNT16. After successful treatment, the increased miR-941 expression in CD14+ monocytes from PsA patients was revoked. The expression of miR-941 in CD14+ monocytes is associated with PsA disease activity. MiR-941 enhances osteoclastogenesis in PsA via WNT16 repression. The miR-941 could be a potential biomarker and treatment target for PsA.

DNA methylation-mediated repression of miR-941 enhances lysine (K)-specific demethylase 6B expression in hepatoma cells

MicroRNAs (miRNAs) have been shown to play important roles in carcinogenesis. However, their underlying mechanisms of action in hepatocellular carcinoma (HCC) are poorly understood. Recent evidence suggests that epigenetic silencing of miRNAs through tumor suppression by CpG island hypermethylation may be a common hallmark of human tumors. Here, we demonstrated that miR-941 was significantly down-regulated in HCC tissues and cell lines and was generally hypermethylated in HCC. The overexpression of miR-941 suppressed in vitro cell proliferation, migration, and invasion and inhibited the metastasis of HCC cells in vivo. Furthermore, the histone demethylase KDM6B (lysine (K)-specific demethylase 6B) was identified as a direct target of miR-941 and was negatively regulated by miR-941. The ectopic expression of KDM6B abrogated the phenotypic changes induced by miR-941 in HCC cells. We demonstrated that miR-941 and KDM6B regulated the epithelial-mesenchymal transition process and affected cell migratory/invasive properties.