Analysis of the IL-6-mediated intracellular signaling molecules in myeloma cell growth

骨髓瘤细胞生长中 IL-6 介导的细胞内信号分子分析

基本信息

批准号：
17590999
负责人：
ISHIKAWA Hideaki
金额：
$ 2.24万
依托单位：
Yamaguchi University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2005
资助国家：
日本
起止时间：
2005 至 2006
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-17590999/
关键词：
myeloma IL-6 signal-transducing molecules Lyn CD45 PI 3-kinase PI3-kinase 質量分析マイクロアレイ IL-6誘導遺伝子

项目摘要

A cytokine, interleukin-6 (IL-6) is a growth factor for human myeloma cells. Upon IL-6 stimulation, signal transducer and activator of transcription (STAT) 3 and extracellular signal-regulated kinase (ERK) 1/2 are activated. We recently found that in myeloma cell lines the activation of both STAT3 and ERK1/2 is not sufficient for the IL-6-induced proliferation, which further requires the activation of the src family protein-tyrosine kinases (PTKs), such as Lyn, associated with the CD45 protein-tyrosine phosphatase (PTP). To explore the molecular mechanism that governs how IL-6 stimulation induces the proliferation of myeloma cells, such as downstream molecules of Lyn, we have established the myeloma cell lines, ILKM2 and ILKM8 overexpressing Lyn. We have found that both the Lyn-overexpressed ILKM2 and ILKM8 have the higher proliferative rate in response to IL-6 than that of their mock counterpart. In contrast, in the absence of IL-6 these Lyn-overexpressed cell lines showed higher susc … More eptibility to cell death. Cell surface expression of IL-6 receptor a and CD45 was not influenced by the Lyn-overexpression. We have also found that the enhanced activation of the phosphatidylinositol 3-kinase (PI3-K) and Akt in the Lyn-overexpressed cells with IL-6, whereas the activation levels of two other major IL-6-responsive molecules, STAT3 and ERK1/2 remained unchanged, indicating that these are the independent signaling pathways of the Lyn-PI3K-Akt. In the Lyn-overexpressed cells, the Lyn PTK seems to be constitutively active because the positive regulatory tyrosine residue in the catalytic domain was highly phosphorylated, while the negative regulatory tyrosine residue in the COOH-terminus was not phosphorylated, presumably due to its dephosphorylation by CD45 PTP. The PI3-K was co-precipitated with Lyn in the immunoprecipitation assay, and specific inhibition of PI3-K or Akt activities by the pharmacologic reagents suppressed the IL-6-induced proliferation of the Lyn-overexpressed cells, suggesting that the activation of the PI3K-Akt pathways associated with the activated Lyn is indeed related to their concomitant augmentation of myeloma cell growth although the downstream signaling molecules are still need to be explicated. Experiments are also underway to clarify the possible mechanisms of the accelerated cell death of the Lyn-overexpressed myeloma cells as a consequence of the IL-6 withdrawal, our work will provide an understanding of Lyn's role in the IL-6 receptor-mediated signaling. Less

细胞因子白细胞介素6（IL-6）是人骨髓瘤细胞的生长因子。在IL-6刺激下，转录3（Stat）3和细胞外信号调节激酶（ERK）1/2的活化剂被激活。我们最近发现，在骨髓瘤细胞系中，STAT3和ERK1/2的激活对于IL-6诱导的增殖不足，这进一步需要激活SRC家族蛋白蛋白 - 酪氨酸激酶（PTK），例如Lyn，例如与CD45蛋白质蛋白质蛋白质蛋白质 - 磷酸糖苷磷酸酶（PTP）相关的LYN。为了探索控制IL-6如何刺激骨髓瘤细胞增殖的分子机制，例如Lyn的下游分子，我们已经建立了骨髓瘤细胞系，ILKM2和ILKM8过表达Lyn。我们发现，响应于IL-6的Lyn越过表达的ILKM2和ILKM8都比其模拟对应物具有更高的增殖率。相比之下，在没有IL-6的情况下，这些lyn倒闭的细胞系显示了更高的SUSC……对细胞死亡的可疑性。 IL-6受体A和CD45的细胞表面表达不受Lyn-Over表达的影响。 We have also found that the enhanced activation of the phosphatidylinositol 3-kinase (PI3-K) and Akt in the Lyn-overexpressed cells with IL-6, whereas the activation levels of two Other major IL-6-responsive molecules, STAT3 and ERK1/2 remained unchanged, indicating that these are the independent signaling pathways of the Lyn-PI3K-Akt.在LYN过表达的细胞中，Lyn PTK似乎一直保持活跃，因为催化结构域中的阳性调节酪氨酸在催化结构域中的阳性保留率高度磷酸化，而COOH-Terminus中的负调节酪氨酸在COOH-terminus中的负磷酸含量并未磷酸化，这可能是由于其由CD45 ptp的Dephosphoryation而导致的。 The PI3-K was co-precipitated with Lyn in the immunoprecipitation assay, and specific inhibition of PI3-K or Akt activities by the pharmaceutical reagents suppressed the IL-6-induced proliferation of the Lyn-overexpressed cells, suggesting that the activation of the PI3K-Akt pathways associated with the activated Lyn is indeed related to their concomitant augmentation of myeloma cell growth although仍然需要明确的下游信号分子。实验也正在进行中，以阐明由于IL-6戒断而导致LYN表达的骨髓瘤细胞加速细胞死亡的可能机制，我们的工作将提供对Lyn在IL-6受体介导的信号传导中的作用的理解。较少的