Roles of AKT1 and AKT2 in non-small cell lung cancer cell survival, growth, and migration
Roles of AKT1 and AKT2 in non-small cell lung cancer cell survival, growth, and migration
复制标题
DOI：
10.1111/j.1349-7006.2011.02025.x
复制
发表时间：
2011-10-01
期刊：
影响因子：
5.7
通讯作者：
Koo, Hong H.
中科院分区：
文献类型：
--
作者：
Lee, Myoung W.;Kim, Dae S.;Koo, Hong H.
尽管 AKT/蛋白激酶 B 在非小细胞肺癌 (NSCLC) 细胞中具有组成型活性，并且是增强治疗药物细胞毒性的有吸引力的靶标，但 AKT 亚型在 NSCLC 中的独特作用在很大程度上尚不清楚。在本研究中，我们使用 RNAi 研究了 AKT1 和 AKT2 在 NSCLC 细胞中的作用。靶向 AKT1 或 AKT2 的 siRNA 分别有效降低了 A549 和 H460 细胞中 AKT1 和 AKT2 的蛋白水平。与对照相比，顺铂处理这些细胞增加了细胞凋亡。 H460 细胞中 siRNA 诱导的 AKT1 敲低显着降低了基础 MEK/ERK1/2 活性，导致核因子 kappa B 激活，而 AKT2 敲低则导致抗凋亡 Bcl-2 家族蛋白 MCL-1 (MCL-1) 裂解、线粒体膜电位崩溃、细胞色素 c 释放和 caspase 级联激活。因此，两种 siRNA 治疗均增强了 H460 细胞对顺铂的化学敏感性。然而，AKT1 和 AKT2 siRNA 处理均不对 p27 表达产生任何影响，尽管两种处理均倾向于诱导 G(2)/M 期阻滞，但效果并不具有统计学意义。 AKT1 siRNA 处理显着降低集落形成生长和迁移，但 AKT2 siRNA 对这些参数没有显着影响。这些数据表明 AKT1 和 AKT2 都有助于细胞存活，尽管通过不同的机制，并且对细胞生长和迁移的影响主要由 AKT1 调节。这些发现可能有助于完善抑制 AKT 亚型以提高 NSCLC 细胞对治疗药物敏感性的靶向策略。 （癌症科学 2011 年；102：1822-1828）
Although AKT/protein kinase B is constitutively active in non-small cell lung cancer (NSCLC) cells and is an attractive target for enhancing the cytotoxicity of therapeutic agents, the distinct roles of the AKT isoforms in NSCLC are largely unknown. In the present study, we investigated the roles of AKT1 and AKT2 in NSCLC cells using RNAi. The siRNA targeting of AKT1 or AKT2 effectively decreased protein levels of AKT1 and AKT2, respectively, in A549 and H460 cells. Cisplatin treatment of these cells increased apoptotic cell death compared with control. The siRNA-induced knockdown of AKT1 in H460 cells significantly decreased basal MEK/ERK1/2 activity, resulting in nuclear factor-kappa B activation, whereas knockdown of AKT2 resulted in anti-apoptotic Bcl-2 family protein MCL-1 (MCL-1) cleavage, the collapse of mitochondrial membrane potential, cytochrome c release, and activation of the caspase cascade. Consequently, both siRNA treatments enhanced the chemosensitivity of H460 cells to cisplatin. However, neither AKT1 nor AKT2 siRNA treatment had any effect of p27 expression, and although both treatments tended to induced G(2)/M phase arrest, the effect was not statistically significant. Treatment with AKT1 siRNA markedly decreased colony formation growth and migration, but AKT2 siRNA had no significant effects on these parameters. These data suggest that AKT1 and AKT2 both contribute to cell survival, albeit via different mechanisms, and that the effects on cell growth and migration are predominantly regulated by AKT1. These findings may aid in refining targeted strategies for the inhibition of AKT isoforms towards the sensitization of NSCLC cells to therapeutic agents. (Cancer Sci 2011; 102: 1822-1828)