不同类型骨髓瘤细胞中IL-6信号途径活化及生物学意义

Activation of two IL 6 signal transduction pathways in different myeloma cell lines and its biological significance

目的：研究具有不同 IL 6反应性的人骨髓瘤细胞中两条 IL 6信号转导途径 JAK/STAT和 Ras/MAPK/NF IL 6的诱导活化情况及生物学意义。方法：首先采用 MTT方法观察 IL 6刺激 XG 7、 KM 3、 U266和 Sko 007 4株 MM细胞后对其生长产生的影响；进而分别采用凝胶阻滞电泳 (electrophoretic mobility shift assay,EMSA)和免疫沉淀 (immunoprecipitation,IP)方法观察参与两条 IL 6信号转导途径的转录因子 STAT3、 NF IL 6和蛋白激酶 JAK1、 MAPK在 IL 6刺激后的诱导活化状态，并确定以上 4株靶细胞中的 IL 6信号转导通路。结果：①以上 MM细胞分别属于“ IL 6生长依赖型” (XG 7)、“ IL 6增殖反应型” (KM 3、 U266)和“非 IL 6增殖反应型” (Sko 007)人骨髓瘤细胞系。 ② 4株 MM细胞中都出现了 Ras/MAPK/NF IL 6途径在 IL 6刺激作用下的诱导活化；而 JAK/STAT途径的激活只见于 Sko 007和 U266这 2株细胞。结论： Ras/MAPK/NF IL 6途径是各类 MM细胞中存在的 IL 6信号转导通路；而 JAK/STAT途径的激活则与处于发育末期的瘤细胞存在一定相关性。

Objective： To investigate the activation of two IL 6 signal transduction pathways JAK/STAT and Ras/MAPK/NF IL 6 in different type of myeloma cell lines and its biological significance. Methods: MTT was firstly used to detect the effect of IL 6 on the growth of four myeloma cell lines XG 7,KM 3,U266 and Sko 007;then electrophoretic mobility shift assay(EMSA) and immunoprecipitation(IP) were used to show the activation of transcription factors STAT3,NF IL 6 and protein kinases JAK1,MAPK in the presence of IL 6,which can represent the activation states of two IL 6 signal transduction pathways,respectively. Results:① The four cell lines were“ IL 6 dependent” (XG 7) or“ IL 6 independent” (KM 3,U266,Sko 007) myeloma cells;and exogenous IL 6 could promote the proliferation of KM 3 and U266 cells,but no effects on the growth of Sko 007 cells.② Ras/MAPK/NF IL 6 pathway was activated by IL 6 in all the four myeloma cells; but the activation of JAK/STAT pathway can be only detected in Sko 007 and U266 cells. Conclusions: Ras/MAPK/NF IL 6 is a general IL 6 signal transduction pathway in myeloma cells;but JAK/STAT pathway prefers to be activated in the cell lines which is related to the late developmental phase of myeloma cells in vivo.