丝裂原活化蛋白激酶在力达霉素抑制鼠骨髓瘤细胞增殖和诱导凋亡中的作用

目的: 研究力达霉素(LDM)对鼠骨髓瘤细胞丝裂原活化蛋白激酶(MAPKs) 信号传导通路的影响及MAPKs在LDM抑制鼠骨髓瘤细胞增殖和诱导凋亡中的作用，为LDM治疗人多发性骨髓瘤的研究提供依据。方法: 选取处于对数生长期鼠骨髓瘤细胞株SP2/0，随机分为空白对照组、4种不同浓度LDM组，采用Western blotting 方法检测各组细胞48 h后MAPK家族的三个主要成员c-Jun氨基末端激酶(JNK)、细胞外信号调节激酶(ERK)和p38 MAPK的表达水平。选取处于对数生长期SP2/0，随机分为对照组、LDM组、SP600125组(JNK抑制剂)、SB203580组(p38抑制剂)、U0126组(ERK抑制剂)、LDM+SP600125组、LDM+SB203580组和LDM+U0126组，采用MTS法和流式细胞术分别检测各组细胞增殖和凋亡情况。结果: 细胞培养48 h后，不同浓度LDM组JNK、ERK和p38 MAPK的表达水平高于空白对照组（P<0.05）；各抑制剂组细胞增殖率和细胞凋亡率与空白对照组比较差异无统计学意义(P>0.05)，即对细胞的增殖抑制和凋亡诱导作用均不明显；但LDM+SP600125组、LDM +SB203580组LDM对细胞的增殖抑制和凋亡诱导作用均降低（P<0.05），而LDM+U0126组LDM对细胞的增殖抑制和凋亡诱导作用则增强（P<0.05）。结论: LDM能够通过激活JNK、p38 MAPK抑制鼠骨髓瘤细胞SP2/0细胞增殖，诱导其凋亡。

Role of mitogen-activated protein kinases in proliferation inhibition and apoptosis induction of lidamycin on mouse myeloma cells

Objective To investigate the effect of lidamycin(LDM) on signal transmission pathway of mitogen-activated protein kinases(MAPKs) in mouse myeloma cells and the role of MAPKs in cell growth and apoptosis induced by LDM,and to provide basis for research on treatment of human multiple myeloma with LDM.Methods The mouse myeloma SP2/0 cells in logarithm growth phase were selected and randomly divided into blank control group and four different concentrations of LDM groups.The expression levels of c-Jun amino-terminal kinase(JNK),extracellular signal-regulated kinase(ERK) and p38 MAPK were detected 48 h after culture by Western blotting.And then the SP2/0 cells in logarithm growth phase were selected and randomly divided into control group,LDM group,SP600125(JNK inhibitor) group,SB203580(p38 inhibitor)group,U0126 group(ERK inhibitor),LDM +SP600125 group,LDM + SB203580 group,and LDM + U0126 group.MTS assay was used to detect SP2/0 cell proliferation and flow cytometry was used to analyze apoptosis in various groups.Results The expression levels of JNK,ERK and p38 MAPK in SP2/0 cells in different concentrations of LDM groups were higher than those in blank control group(P<0.05) 48 h after culture;Compared with blank control group,the apoptotic rates and proliferation rates in different inhibitors groups had no significant differences(P>0.05),in other words,the proliferation inhibition and apoptosis induction in SP600125 group,SB203580 group,and U0126 group were not obvious.The effects of LDM on the growth inhibition and apoptosis of cells were decreased in LDM +SP600125 group and LDM + SB203580 group(P<0.05)and increased in LDM + U0126 group(P<0.05).Conclusion LDM can inhibit the proliferation of mouse myeloma SP2/0 cells and induce apoptosis through activation of JNK and p38 MAPK.