目的 探讨核受体亚家族0B组成员1（NR0B1）在类风湿关节炎关节（RA）滑膜组织中的时空表达规律，揭示人成纤维细胞样滑膜细胞（FLS）中调控NR0B1表达的潜在上游信号，从而明确诱发RA滑膜中NR0B1表达紊乱的可能因素。 方法 招募未接受任何免疫治疗的RA患者25名及骨关节炎（OA）患者18名，获取膝关节滑膜组织，Real-time PCR、Western blotting、免疫组织化学和免疫荧光双重染色检测NR0B1在滑膜中的表达，Pearson卡方检验评估NR0B1基因mRNA水平与RA患者临床指标的相关性。构建稳定敲低NR0B1的MH7ANR0B1/细胞，细胞活力和凋亡检测、集落形成实验、细胞划痕和侵袭实验评估敲低NR0B1对血管内皮生长因子（VEGF）刺激下FLS表型的影响；通过STAT3特异性抑制剂干预、siRNA、双荧光素酶报告基因检测分析白细胞介素6（IL-6）通过STAT3信号调控NR0B1基因转录表达的分子机制。 结果 NR0B1基因mRNA在RA滑膜组织表达水平显著高于OA滑膜（P<0.05），此高表达趋势分别与RA临床指标C-反应蛋白（CRP）、类风湿因子（RF）、红细胞沉降速度（ESR）成显著正相关；NR0B1蛋白定位于FLS。敲低NR0B1显著抑制VEGF对MH7A细胞活力、凋亡抵抗性、集落形成能力、迁移和侵袭的增强作用。此外，IL-6能特异性上调MH7A滑膜细胞中NR0B1基因的表达水平；IL-6主要通过诱导下游STAT3的Tyr-705位点磷酸化，进而促进后者STAT3对NR0B1的转录激活。 结论 FLS的NR0B1表达上调与RA疾病进展密切相关；IL-6通过诱导下游STAT3的Tyr-705位点磷酸化激活NR0B1基因的转录表达；NR0B1可能为解析IL-6与VEGF信号通路相互作用与RA进展的重要突破点。 

Objective To investigate the spatio-temporal expression of nuclear receptor subfamily 0 group B member 1 (NR0B1) in synovial tissues of rheumatoid arthritis (RA), and to uncover the potential upstream signalling pathway that may regulate NR0B1 expression in human fibroblast-like synovial cells, thereby clarifying the possible factors that induce the disorder of NR0B1 expression in RA.    Methods Patients with 25 RA and 18 osteoarthritis (OA) who did not receive any immunotherapy were recruited to obtain the synovial tissues of knee joint, as well as their related clinical test information, and the expression characteristics of NR0B1 in synovial tissue were investigated using Real-time PCR, Western blotting, immunohistochemistry and double immunofluorescent staining. Meanwhile, Pearson Chi square test was used to evaluate the correlation between NR0B1 mRNA expression level and clinical parameters in RA patients. Furthermore, the MH7ANR0B1-/- cells that were stably knocked down of endogenous NR0B1 were generated, and the effects of NR0B1 deficiency on the phenotype of rheumatoid synovial cells enhanced by vascular endothelial growth factor(VEGF) were then evaluated by means of cell viability and apoptosis assays, colony formation assay, wound healing assay, and cell invasion assay. Last, we studied the molecular mechanism underlying interleuikin 6(IL-6)-mediated regulation of NR0B1 expression at the transcriptional level by using the STAT3-specific inhibitor intervention, siRNA, and dual luciferase reporter gene detection.   Results The expression level of NR0B1 mRNA in the RA synovial tissues was significantly higher than that in synovial tissues from OA patients (P<0.05). This trend of the increased NR0B1 mRNA expression correlated to clinical parameters, including C-reactive protein (CRP), rheumatoid factor (RF) and erythrocyte sedimentation rate (ESR), in RA patients. NR0B1 protein was predominantly immunolocalized in fibroblast-like synoviocytes of RA synovial tissues. Functionally, knockdown of NR0B1 expression markedly neutralize the VEGF-mediated enhancement of cell viability, resistance to apoptosis, clonogenicity, as well as migration and invasion in the MH7A cells. Additionally, IL-6 could specifically regulate NR0B1 expression in the MH7A synovial cells. IL-6 upregulated the transcriptional expression of NR0B1 mainly through induction of the phosphorylation of its downstream STAT3 at the Tyr-705 site.  Conclusion The upregulated NR0B1 expression in fibroblast-like synoviocytes is positively correlated with the progression of RA. The proinflammatory cytokine IL-6 potentiates the transactivation of NR0B1 by inducing the phosphorylation of Tyr-705 site of its downstream effector STAT3. NR0B1 may be a significant breakthrough point for understanding the interaction between IL-6 and VEGF signaling pathways and the progression of RA.