Han Yu-Hui, Xia Li, Song Li-Ping, Zheng Ying, Chen Wen-Li, Zhang Lei, Huang Ying, Chen Guo-Qiang, Wang Li-Shun
Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Rui-Jin Hospital, Shanghai Jiao-Tong University School of Medicine, Shanghai, P. R. China.
Proteomics. 2006 Jun;6(11):3262-74. doi: 10.1002/pmic.200500754.
We reported recently that moderate hypoxia and hypoxia-mimetic agents could induce growth arrest and differentiation of leukemic cells via the mediation of hypoxia-inducible factor 1 alpha (HIF-1alpha), but the exact molecular mechanisms remain largely unknown. In this study, human acute promonocytic leukemic U937 cells were incubated under 2% O2 or in 50 microM of the hypoxia mimetic agent cobalt chloride (CoCl2) and normal oxygen for 24 h, and their protein expression profiles were compared by 2-DE coupled with MALDI-TOF/TOF MS/MS. We identified 62 and 16 proteins that were significantly deregulated by hypoxia and CoCl2 treatment, respectively. These proteins were mainly involved in metabolism, gene expression regulation, signal transduction, cell proliferation, differentiation and apoptosis. As an example, N-myc downstream regulated gene 1 (NDRG1), a putative differentiation-related gene, was up-regulated in both 2% O2- and CoCl2-treated U937 cells. Moreover, enforced HIF-1alpha expression also elevated NDRG1 mRNA and protein in U937 cells. These data will provide some clues for understanding mechanisms by which leukemic cells response to hypoxia.
我们最近报道，中度缺氧和缺氧模拟剂可通过缺氧诱导因子1α（HIF-1α）的介导诱导白血病细胞生长停滞和分化，但确切的分子机制仍 largely 未知。在本研究中，将人急性早幼粒细胞白血病 U937 细胞在 2% O2 条件下或在 50 microM 的缺氧模拟剂氯化钴（CoCl2）中以及正常氧气条件下孵育 24 小时，并通过二维电泳（2-DE）结合基质辅助激光解吸电离飞行时间串联质谱（MALDI-TOF/TOF MS/MS）比较它们的蛋白质表达谱。我们分别鉴定出 62 种和 16 种因缺氧和 CoCl2 处理而显著失调的蛋白质。这些蛋白质主要参与代谢、基因表达调控、信号转导、细胞增殖、分化和凋亡。例如，N-myc 下游调控基因 1（NDRG1），一个假定的分化相关基因，在 2% O2 和 CoCl2 处理的 U937 细胞中均上调。此外，强制表达 HIF-1α 也提高了 U937 细胞中 NDRG1 的 mRNA 和蛋白质水平。这些数据将为理解白血病细胞对缺氧反应的机制提供一些线索。
