Establishment of new molecular-targeted therapy for leukemia mediated through HIF-1 regulation by ROS

ROS介导的HIF-1调控白血病新分子靶向治疗的建立

基本信息

批准号：
17591010
负责人：
KIZAKI Masahiro
金额：
$ 2.24万
依托单位：
KEIO 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-17591010/
关键词：
leukemia molecular target HIF-1 reactive oxygen species transcription factor apoptosis natural product cell cycle

项目摘要

The therapeutic approach to leukemia is based on chemotherapy, but the side effects of the drugs used and various complications are sometimes fatal. Recently, molecular-targeted therapy is pay attention in the clinical setting ; therefore, we have sought out new agents to establish the more non-invasive therapy for the patients with leukemiaWe have reported that reactive oxygen species (ROS) are key mediators of apoptosis induced by a green tea polyphenol, (-)-epigallocatechin-3-gallate (EGCG). EGCG rapidly induced apoptosis in MPO-positive, but not MPO-negative leukemia cell lines as well as fresh samples from AML. Pre-incubation of MPO-positive leukemic cells with the MPO-specific inhibitor, 4-aminobenzoic acid hydrazide (ABAH), and the heme biosynthesis inhibitor, succinylacetone (ScAc), resulted in inhibition of the ROS production and induction of apoptosis following addition of EGCG. To investigate the role of MPO in EGCG-induced apoptosis, we transfected the full length MPO cDNA … More and empty vector into MPO-negative K562 cells. In contrast to control cells, MPO transfected cells enhanced MPO activity and ROS production, and sensitized EGCG-resistant K562 cells to apoptosis induced by ROS-producing agents. In addition, an enzymatically inactive MPO mutant expressing K562 (K562/H502A) cells could not respond to EGCG, suggesting that MPO is important for determining the sensitivity to EGCG-induced oxidative stress. Further, it is noteworthy that the fluorescence intensity of both APF-and HPF-loaded myeloid leukemic cells significantly increased upon stimulation with EGCG suggesting that EGCG generated highly toxic ROS in MPO-positive leukemic cells. Taken together, these observations indicate that highly toxic ROS such as hydroxyl radical generated via the H_2O_2/MPO/halide system induce apoptosis, and that such ROS may be the direct mediators of oxidative stress-induced apoptosis in MPO-positive leukemic cells. Gene expression profiling with Affimetrix gene chips demonstrated HIF-1α and its down-stream genes (RTP801,EGR-1,BNIP3, and VEGF), that were up-regulated, suggesting that HIF-1α pathways will be important for ROS-mediated apoptosis. Less

白血病的治疗方法基于化学疗法，但是使用的药物和各种并发症的副作用有时是致命的。最近，靶向分子靶向疗法是在临床环境中注意的。因此，我们已经寻求新的药物来为白血病患者建立更无创的疗法，报道说，活性氧（ROS）是由绿茶多酚，（ - ） - epigallocatechin-3-gallate（EGCG）诱导的凋亡的关键介体。 EGCG迅速诱导MPO阳性但MPO阴性白血病细胞系以及来自AML的新鲜样品的凋亡。 MPO阳性白血病细胞与MPO特异性抑制剂，4-氨基苯甲酸肼（ABAH）和血红素生物合成抑制剂琥珀酸酯（SCAC）的预孵育，导致抑制ROS的产生和添加EGCG后的凋亡。为了研究MPO在EGCG诱导的细胞凋亡中的作用，我们将全长的MPO cDNA翻译为MPO阴性的K562细胞。与对照细胞相反，MPO翻译细胞增强了MPO活性和ROS产生，以及对EGCG抗EGCG的K562细胞对产生ROS产生剂诱导的凋亡。此外，表达K562（K562/H502A）细胞的酶非活性MPO突变体无法响应EGCG，这表明MPO对于确定对EGCG诱导的氧化应激的敏感性很重要。此外，值得注意的是，APF和HPF负载的髓样白血病细胞的荧光强度在用EGCG刺激后显着增加，这表明EGCG在MPO阳性白血病细胞中产生了剧毒ROS。综上所述，这些观察结果表明，通过H_2O_2/MPO/卤化物系统产生的剧毒ROS，例如羟基自由基诱导的细胞凋亡，并且这种ROS可能是MPO阳性白血病细胞中氧化应激诱导的凋亡的直接介体。用Axpimetrix基因芯片进行基因表达分析表明HIF-1α及其下游基因（RTP801，EGR-1，BNIP3和VEGFF）被上调，这表明HIF-1α途径对ROS介导的细胞凋亡至关重要。较少的