Blockade of transforming growth factor-β-activated kinase 1 activity enhances TRAIL-induced apoptosis through activation of a caspase cascade
Blockade of transforming growth factor-β-activated kinase 1 activity enhances TRAIL-induced apoptosis through activation of a caspase cascade
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DOI：
10.1158/1535-7163.mct-06-0379
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发表时间：
2006-12-01
影响因子：
5.7
通讯作者：
Sakurai, Hiroaki
中科院分区：
文献类型：
--
作者：
Choo, Min-Kyung;Kawasaki, Noritaka;Sakurai, Hiroaki
肿瘤坏死因子（TNF）相关凋亡诱导配体（TRAIL/Apo 2L）是选择性诱导多种肿瘤细胞凋亡的TNF-α配体家族成员。为了阐明TRAIL诱导细胞凋亡的分子机制，我们重点研究了转化生长因子-β-活化激酶1（TAK 1）丝裂原活化蛋白激酶（MAPK）激酶，这是TNF-α诱导的p65/ReIA和c-Jun NH 2-末端激酶/p38 MAPK活化的关键调节因子。在人宫颈癌HeLa细胞中，TRAIL诱导内源性TAK 1及其激活蛋白TAB 1和TAB 2的延迟磷酸化，这与TNF-α的快速反应形成对比。使用小干扰RNA（siRNA）特异性敲除TAK 1消除了TRAIL诱导的p65和c-Jun NH 2-末端激酶/p38 MAPK的激活。TRAIL诱导的凋亡信号，包括caspase-8，caspase-3，caspase-7，和聚（ADP-核糖）聚合酶，增强TAK 1 siRNA。流式细胞术显示，TRAIL与TAM siRNA的组合也协同增加了Annexin V与细胞表面的结合。此外，预处理细胞与5 Z-7-oxozeaenol，选择性TAK 1激酶抑制剂，增强TRAIL诱导的半胱氨酸蛋白酶的切割和结合的Annexin V。TAK 1介导的抗凋亡作用也观察到在人肺腺癌A549细胞。相反，TAK 1缺陷小鼠胚胎成纤维细胞对TRAIL诱导的细胞凋亡具有抗性，并且用5 Z7-oxozeaenol处理对照小鼠胚胎成纤维细胞没有显著促进TRAIL诱导的半胱天冬酶级联的活化。这些结果表明，TAK 1在TRAIL诱导的细胞凋亡中起着关键作用，阻断TAK 1激酶将提高战胜癌症的机会。
Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL/Apo2L) is a member of the TNF-(x ligand family that selectively induces apoptosis in a variety of tumor cells. To clarify the molecular mechanism of TRAIL-induced apoptosis, we focused on transforming growth factor-beta-activated kinase 1 (TAK1) mitogen-activated protein kinase (MAPK) kinase kinase, a key regulator of the TNF-alpha-induced activation of p65/ReIA and c-Jun NH2-terminal kinase/p38 MAPKs. In human cervical carcinoma HeLa cells, TRAIL induced the delayed phosphorylation of endogenous TAK1 and its activator protein TAB1 and TAB2, which contrasted to the rapid response to TNF-alpha. Specific knockdown of TAK1 using small interfering RNA (siRNA) abrogated the TRAIL-induced activation of p65 and c-Jun NH2-terminal kinase/p38 MAPKs. TRAIL-induced apoptotic signals, including caspase-8, caspase-3, caspase-7, and poly(ADP-ribose) polymerase, were enhanced by TAK1 siRNA. Flow cytometry showed that the binding of Annexin V to cell surface was also synergistically increased by TRAIL in combination with TAM siRNA. In addition, pretreatment of cells with 5Z-7-oxozeaenol, a selective TAK1 kinase inhibitor, enhanced the TRAIL-induced cleavage of caspases and binding of Annexin V. The TAK1-mediated antiapoptotic effects were also observed in human lung adenocarcinoma A549 cells. In contrast, TAK1-deficient mouse embryonic fibroblasts are resistant to TRAIL-induced apoptosis, and treatment of control mouse embryonic fibroblasts with 5Z7-oxozeaenol did not drastically promote the TRAIL-induced activation of a caspase cascade. These results suggest that TAK1 plays a critical role for TRAIL-induced apoptosis, and the blockade of TAK1 kinase will improve the chances of overcoming cancer.