Figure 2.

Higher levels of XIST expression in OA synovial tissue and knockdown of XIST inhibited VCAM-1-mediated monocyte adherence. (A) An analysis of the GEO dataset GDS4195 identified the top 20 upregulated lncRNAs in human OA synovial tissue specimens (n = 5). (B) A cluster heat map shows lncRNA expression in human synovial tissue (red denotes higher expression and blue denotes lower expression) from the GEO dataset GDS5401. (C) Levels of XIST expression in OA (n = 10) and healthy synovial tissue (n = 10) samples from GDS5401. (D) Total RNA for each sample of human synovium was extracted using TRIzol reagent. Levels of XIST were quantified by RT-qPCR assay (n = 3). (E, F) OASFs were transfected with XIST siRNA for 24 h. The RT-qPCR assay measured XIST and VCAM-1 expression (n = 3). (G) OASFs were co-transfected with XIST siRNA and the VCAM-1 OV plasmid for 24 h. THP-1 cells were labeled with the green fluorescence BCECF-AM (10 μM) for 1 h. After washing the unlabeled THP-1 cells, they were resuspended in a serum-free RPMI medium and then co-cultured with OASFs for 1 h. Fluorescence intensity was measured by Zeiss AxioPhot fluorescence microscopy in the images and quantified by ImageJ processing software in three independent experiments (H). TUG1, taurine upregulated gene 1. ^* p < 0.05, ^** p < 0.01, ^*** p < 0.001, ^**** p < 0.0001 compared with control siRNA; ^## p < 0.01 compared with XIST siRNA.