Department of Chemistry and Institute of Chemistry, National Dong Hwa University, Hualien, Taiwan.
Mol Cell Biochem. 2011 Feb;348(1-2):129-39. doi: 10.1007/s11010-010-0647-7. Epub 2010 Nov 11.
Interleukin 6 is the in vivo growth factor of myeloma cells. In response to IL-6 stimulation, the PI3K/AKT signaling pathway is activated in these cells. With comparative proteomic approaches, this study reveals many putative downstream effectors of the PI3K/AKT pathway. Mass spectrometry analysis of excised protein spots from 2-dimensional gel allowed the identification of proteins such as β-Actin, cyclophilin A, E3 SUMO-protein ligase PIAS-NY protein, HSP 27, PML, and transforming growth factor β-2. Among these putative effectors, β-Actin was chosen for further characterization. Phosphorylation of β-Actin by AKT upon IL-6 stimulation was confirmed by western blotting using a phospho-AKT substrate antibody. Interestingly, IL-6 significantly increased cell migration (P < 0.05) and the content of filamentous actin (P < 0.05). Therefore, IL-6 stimulation could have effects on the migration of myeloma cells, and the phosphorylation of β-Actin is probably involved in the process.
白细胞介素 6 是骨髓瘤细胞的体内生长因子。在受到白细胞介素 6 的刺激后，这些细胞中的 PI3K/AKT 信号通路被激活。通过比较蛋白质组学方法，本研究揭示了 PI3K/AKT 通路的许多潜在下游效应物。从 2 维凝胶中切下的蛋白斑点的质谱分析允许鉴定出诸如β-肌动蛋白、亲环蛋白 A、E3 SUMO-蛋白连接酶 PIAS-NY 蛋白、HSP27、PML 和转化生长因子β-2 等蛋白。在这些潜在的效应物中，β-肌动蛋白被选择用于进一步表征。通过使用磷酸化 AKT 底物抗体进行 Western blot 验证了 AKT 在白细胞介素 6 刺激下对 β-肌动蛋白的磷酸化。有趣的是，白细胞介素 6 显著增加了细胞迁移（P < 0.05）和丝状肌动蛋白的含量（P < 0.05）。因此，白细胞介素 6 的刺激可能对骨髓瘤细胞的迁移有影响，而β-肌动蛋白的磷酸化可能参与了这一过程。
