Simultaneous inhibition of PDK1/AKT and Fms-like tyrosine kinase 3 signaling by a small-molecule KP372-1 induces mitochondrial dysfunction and apoptosis in acute myelogenous leukemia.
Simultaneous inhibition of PDK1/AKT and Fms-like tyrosine kinase 3 signaling by a small-molecule KP372-1 induces mitochondrial dysfunction and apoptosis in acute myelogenous leukemia.
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DOI：
10.1158/0008-5472.can-05-1278
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发表时间：
2006-04
期刊：
影响因子：
11.2
通讯作者：
Z. Zeng;I. Samudio;Weiguo Zhang;Z. Estrov;H. Pelicano;D. Harris;O. Frolova;N. Hail;Wenjing Chen-Wenji
中科院分区：
文献类型：
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作者：
Z. Zeng;I. Samudio;Weiguo Zhang;Z. Estrov;H. Pelicano;D. Harris;O. Frolova;N. Hail;Wenjing Chen-Wenji
磷酸肌醇 3 激酶 (PI3K)/蛋白激酶 B (AKT) 和 Fms 样酪氨酸激酶 3 (FLT3) 信号在急性髓性白血病 (AML) 细胞中异常激活。持续激活的 AKT 和 FLT3 调节白血病细胞的存活和化疗耐药性。在这项研究中，我们研究了新型多激酶抑制剂 KP372-1 对 AML 细胞系和原发性 AML 样本存活的影响。 KP372-1 以浓度依赖性方式直接抑制 AKT、PDK1 和 FLT3 的激酶活性。 Western blot 分析表明，KP372-1 降低了 AKT Ser(473) 和 Thr(308) 上的磷酸化；通过 PI3K/AKT 信号传导消除 p70S6 激酶、BAD 和 Foxo3a 的磷酸化；并通过直接抑制FLT3下调PIM-1的表达。用 KP372-1 处理 AML 细胞系会导致活性氧的快速产生并刺激耗氧量，随后发生线粒体去极化、半胱天冬酶激活和磷脂酰丝氨酸外化。 KP372-1 在 AML 细胞系和原代样本中诱导明显的细胞凋亡，无论其 FLT3 状态如何，但在正常 CD34(+) 细胞中则不然。此外，KP372-1 显着降低原代 AML 样本的集落形成能力 (IC(50) < 200 nmol/L），同时对正常祖细胞的细胞毒性作用最小。综上所述，我们的结果表明，KP372-1 同时抑制关键的促生存激酶会导致 AML 的线粒体功能障碍和细胞凋亡，但不会导致正常造血祖细胞。
Phosphoinositol-3-kinase (PI3K)/protein kinase B (AKT) and Fms-like tyrosine kinase 3 (FLT3) signaling are aberrantly activated in acute myelogenous leukemia (AML) cells. Constitutively activated AKT and FLT3 regulate leukemia cell survival and resistance to chemotherapy. In this study, we investigated the effects of the novel multiple kinase inhibitor KP372-1 on the survival of AML cell lines and primary AML samples. KP372-1 directly inhibited the kinase activity of AKT, PDK1, and FLT3 in a concentration-dependent manner. Western blot analysis indicated that KP372-1 decreased the phosphorylation of AKT on both Ser(473) and Thr(308); abrogated the phosphorylation of p70S6 kinase, BAD, and Foxo3a via PI3K/AKT signaling; and down-regulated expression of PIM-1 through direct inhibition of FLT3. Treatment of AML cell lines with KP372-1 resulted in rapid generation of reactive oxygen species and stimulation of oxygen consumption, followed by mitochondrial depolarization, caspase activation, and phosphatidylserine externalization. KP372-1 induced pronounced apoptosis in AML cell lines and primary samples irrespective of their FLT3 status, but not in normal CD34(+) cells. Moreover, KP372-1 markedly decreased the colony-forming ability of primary AML samples (IC(50) < 200 nmol/L) with minimal cytotoxic effects on normal progenitor cells. Taken together, our results show that the simultaneous inhibition of critical prosurvival kinases by KP372-1 leads to mitochondrial dysfunction and apoptosis of AML but not normal hematopoietic progenitor cells.