Increased phosphorylation of ezrin/radixin/moesin proteins contributes to proliferation of rheumatoid fibroblast-like synoviocytes
Increased phosphorylation of ezrin/radixin/moesin proteins contributes to proliferation of rheumatoid fibroblast-like synoviocytes
复制标题
埃兹蛋白/根蛋白/莫斯蛋白磷酸化的增加有助于类风湿成纤维细胞样滑膜细胞的增殖。
DOI：
10.1093/rheumatology/keq440
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发表时间：
2011-06-01
期刊：
影响因子：
5.5
通讯作者：
Xu, Hanshi
中科院分区：
文献类型：
--
作者：
Huang, Hongwei;Xiao, Youjun;Xu, Hanshi
目标.越来越多的证据表明，ezrin/radixin/moesin（ERM）蛋白可能在细胞增殖中发挥关键作用。本研究探讨了ERM蛋白在RA患者成纤维细胞样滑膜细胞（FLS）增殖中的作用。滑膜组织（ST）来自18例RA和6例OA患者。用免疫印迹法或IF染色法检测培养的FLS和ST中ERM及其磷酸化蛋白的表达。使用小干扰RNA（siRNA）介导的ERM敲低来抑制ERM的磷酸化。用溴脱氧尿苷（BrdU）掺入法和PCNA免疫印迹法检测FLS的增殖情况。我们的研究表明，与OA患者和非关节炎对照组相比，RA患者ST和FLS中的ERM蛋白磷酸化水平增加。TNF-α、IL-1 β或PDGF可诱导RA FLS以剂量和时间依赖性方式磷酸化ERM蛋白，但不影响总ERM蛋白的表达。Rho激酶和p38 MAPK信号通路参与TNF-α诱导的ERM磷酸化。我们进一步表明，通过siRNA介导的ERM敲低抑制ERM磷酸化可抑制RA FLS中TNF-α或IL-1 β诱导的BrdU掺入和PCNA表达。本研究提供了新的证据，表明ERM蛋白的磷酸化增加可能有助于RA FLS的增殖，提示特异性抑制ERM磷酸化可能是RA治疗的新途径。
Objectives. Increasing evidence indicates that ezrin/radixin/moesin (ERM) proteins may play a critical role in cell proliferation. This study examined the role of ERM proteins in proliferation of fibroblast-like synoviocytes (FLS) from patients with RA.Methods. Synovial tissues (STs) were obtained from 18 RA and 6 OA patients. The expression of ERM and its phosphorylated proteins in cultured FLS and ST was assessed by western blots or IF staining. Small interference RNA (siRNA)-mediated ERM knockdown was used to inhibit phosphorylation of ERM. Proliferation of FLS was measured by bromodeoxyuridine (BrdU) incorporation into cell DNA and by PCNA immunoblotting.Results. Our study showed that increased phosphorylation of ERM proteins was found in ST and FLS from patients with RA as compared with OA patients and non-arthritis controls. Treatment with TNF-alpha, IL-1 beta or PDGF-induced phosphorylation of ERM proteins in dose- and time-dependent manner by RA FLS, but did not affect the expression of total ERM protein. Rho kinase and p38MAPK signal pathways were involved in TNF-alpha-induced ERM phosphorylation. We further showed that inhibition of ERM phosphorylation by siRNA-mediated ERM knockdown suppressed TNF-alpha- or IL-1 beta-induced BrdU incorporation and PCNA expression in RA FLS.Conclusions. This study provides the novel evidence that increased phosphorylation of ERM proteins may contribute to proliferation of RA FLS, suggesting that specific inhibition of ERM phosphorylation may be a new therapeutic approach for RA.