Contribution of STAT3 to the activation of survivin by GM-CSF in CD34+ cell lines
Contribution of STAT3 to the activation of survivin by GM-CSF in CD34+ cell lines
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DOI：
10.1016/j.exphem.2007.03.007
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发表时间：
2007-06-01
影响因子：
2.6
通讯作者：
Zhou, Muxiang
中科院分区：
文献类型：
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作者：
Gu, Lubing;Chiang, Kuang-Yueh;Zhou, Muxiang
目标。粒细胞巨噬细胞集落刺激因子(GM-CSF)能特异性刺激CD34(+)造血祖细胞增殖。尽管信号转导和转录激活因子3(STAT3)被认为在GM-CSF诱导的细胞增殖的信号转导中是必不可少的，但STAT3介导的信号转导并不完全清楚。由于Survivin通过其抗凋亡功能调节细胞的增殖和存活，我们研究了CD34(+)细胞中STAT3信号与Survivin表达的关系。Western印迹法检测GM-CSF诱导的CD34(+)细胞中STAT3和Survivin的表达。通过基因转染法和报告基因测定法分析GM-CSF激活的Survivin启动子活性。染色质免疫沉淀和凝胶迁移率改变分析检测STAT3与Survivin启动子的结合。用Western blotting和流式细胞术检测Janus家族酪氨酸激酶(JAK)抑制剂和STAT3小干扰RNA(SiRNA)对细胞凋亡的影响。我们发现GM-CSF刺激CD34(+)KG-1细胞中Survivin启动子的活性，并且STAT3与核心Survivin启动子结合，该启动子含有STAT反应元件TT(N)(5)aa，位于-264到-256位。该STAT反应元件的突变或缺失完全消除了GM-CSF对Survivin启动子活性的影响。此外，加入JAK抑制剂或STAT3 siRNA均可抑制GM-CSF诱导的Survivin启动子活性和Survivin表达。在GM-CSF依赖的CD34(+)细胞株TF-1中，通过STAT3 siRNA抑制Survivin或通过撤销GM-CSF抑制Survivin抑制细胞生长和增加细胞凋亡率。综上所述，我们的结果提示Survivin是STAT3的转录靶点，GM-CSF刺激的CD34(+)细胞的增殖受JAK/STAT3/Survivin信号通路的调控。(C)2007年国际实验血液学学会。由爱思唯尔公司出版。
Objective. Granulocyte macrophage colony-stimulating factor (GM-CSF) has been shown to specifically stimulate proliferation of CD34(+) hematopoietic progenitor cells. Although signal transducers and activators of transcription 3 (STAT3) is believed essential for transduction of GM-CSF-induced cell proliferation, the signaling mediated by STAT3 is not completely understood. Because survivin regulates cell proliferation and survival via its antiapoptotic function, we studied the link between STAT3 signaling and survivin expression in CD34(+) cells.Methods. GM-CSF-induced STAT3 and survivin expression in CD34(+) cells was examined by Western blot assay. GM-CSF-activated survivin promoter activity was analyzed by gene transfection and reporter assays. The binding of STAT3 to the survivin promoter was evaluated by chromatin immunoprecipitation and electrophoretic mobility shift assay. Western blotting and flow cytometry were utilized to test the effect of Janus family of tyrosine kinases (JAK) inhibitor and STAT3 small interfering RNA (siRNA) on cell apoptosis.Results. We found that GM-CSF stimulates survivin promoter activity in CD34(+) KG-1 cells, and STAT3 binds to the core survivin promoter containing a STAT response element TT(N)(5)AA at sites -264 to -256. Mutation or deletion of this STAT response element completely abolished the effects of GM-CSF on survivin promoter activity. Furthermore, addition of either JAK inhibitor or STAT3 siRNA was able to inhibit GM-CSF-induced survivin promoter activity and survivin expression. Inhibition of survivin by STAT3 siRNA or by withdrawal of GM-CSF in a GM-CSF-dependent, CD34(+) line TF-1 decreased cell growth and increased apoptosis.Conclusion. Altogether, our results suggest that survivin is a transcriptional target of STAT3, and that GM-CSF-stimulated CD34(+) cell proliferation is regulated by the JAK/STAT3/survivin signaling pathway. (c) 2007 International Society for Experimental Hematology. Published by Elsevier Inc.