Analysis of the mechanism of apperance of the autocrine motility factor in rheumatoid arthritis

自分泌运动因子(AMF)是肿瘤细胞分泌的一种细胞因子，可刺激细胞在体内迁移和体外转移。我们不仅在类风湿关节炎(RA)患者的滑液中发现了细胞的运动活性，而且在血清中也发现了细胞的运动活性。由于该酶的生化性质与AMF相同，因此我们确认该酶为AMF。对AMF进行分离、纯化和微测序。研究结果表明，AMF是先前克隆的神经白介素酶和磷酸己糖异构酶(PHI)，与细胞运动有关，是肿瘤进展的标志物。PHI催化葡萄糖-6-磷酸异构化为果糖-6-磷酸，对这两种糖都有专一性。由于PHI是糖酵解代谢的关键酶，与FDG在组织内的积累有关，因此它在肿瘤细胞或炎症细胞中葡萄糖代谢活跃的部位发挥着重要作用。葡萄糖类似物FDG被广泛用于FDG-PET成像评估各种肿瘤。FDG计算的标准摄取值(SUV)可作为炎症反应的定量指标。反映RA疾病活动性的Lansbury指数与FDG-SUV值有很好的相关性。血清CRP值和血小板数与FDG-SUV值也有较好的相关性。组织病理学检查显示，FDG-SUV值随新生血管程度的增加而升高，由于滑膜细胞等炎症细胞在类风湿滑膜关节中的增殖，AMF被认为在炎症活动部位有较大贡献。

The autocrine motility factor (AMF) which tumor secreted as a cytokine stimulates cell migration in vivo and metastasis in vitro. We identified cell motile activity not only in synovial fluid but also in serum of patients with rheumatoid arthritis (RA). Because the biochemical features of this activity were same as that of AMF, we confirm this activity to be AMF. AMF was isolated, purified, and microsequenced. And the results demonstrated that AMF is the previously cloned enzyme designed as Neuroleukin, and Phosphohexose isomerase (PHI), which has been independently implicated in cell motility, and to be a cancer progression marker. PHI catalyzes isomerization of glucose 6-phosphate to fructose 6-phosphate and specific for both sugars. Because PHI is a key enzyme of glycolytic metabolism related to accumulation of FDG within tissue, it plays an important role at a site where has an active glucose metabolism in tumor cells, or inflammatory cells. The glucose analogue, FDG, is widely used to evaluate various tumors with FDG-PET imaging. The standardized uptake value (SUV) calculated with FDG can be used as a quantitative marker of inflammation. The Lansbury index, which indicates disease activity of RA, has efficient correlation with FDG-SUV value. Serum CRP value and the number of platelet have also efficient correlation with FDG-SUV value. Histopathological examination shows that FDG-SUV value is high as the degree of neovasculization.Because synoviocytes and other inflammatory cells proliferate in rheumatoid synovial joints, AMF is considered to make a great contribution in the site of active inflammation.