III Medical Department, Technische Universität München, Munich, Germany.
Blood. 2010 Sep 2;116(9):1498-505. doi: 10.1182/blood-2009-11-251074. Epub 2010 Jun 2.
Myc oncoproteins promote continuous cell growth, in part by controlling the transcription of key cell cycle regulators. Here, we report that c-Myc regulates the expression of Aurora A and B kinases (Aurka and Aurkb), and that Aurka and Aurkb transcripts and protein levels are highly elevated in Myc-driven B-cell lymphomas in both mice and humans. The induction of Aurka by Myc is transcriptional and is directly mediated via E-boxes, whereas Aurkb is regulated indirectly. Blocking Aurka/b kinase activity with a selective Aurora kinase inhibitor triggers transient mitotic arrest, polyploidization, and apoptosis of Myc-induced lymphomas. These phenotypes are selectively bypassed by a kinase inhibitor-resistant Aurkb mutant, demonstrating that Aurkb is the primary therapeutic target in the context of Myc. Importantly, apoptosis provoked by Aurk inhibition was p53 independent, suggesting that Aurka/Aurkb inhibitors will show efficacy in treating primary or relapsed malignancies having Myc involvement and/or loss of p53 function.
癌基因蛋白通过控制关键细胞周期调控因子的转录来促进细胞的持续生长。在这里,我们报告 Myc 调节 Aurora A 和 B 激酶(Aurka 和 Aurkb)的表达,并且在小鼠和人类的 Myc 驱动的 B 细胞淋巴瘤中,Aurka 和 Aurkb 的转录本和蛋白水平显著升高。Myc 对 Aurka 的诱导是转录性的,并且通过 E 盒直接介导,而 Aurkb 则是间接调控的。用选择性 Aurora 激酶抑制剂阻断 Aurka/b 激酶活性会引发短暂的有丝分裂阻滞、多倍体化和 Myc 诱导的淋巴瘤凋亡。Myc 诱导的淋巴瘤中,对激酶抑制剂耐药的 Aurkb 突变体可选择性绕过这些表型,表明 Aurkb 是 Myc 背景下的主要治疗靶点。重要的是,Aurk 抑制引起的凋亡与 p53 无关,这表明 Aurka/Aurkb 抑制剂将在治疗具有 Myc 参与和/或 p53 功能丧失的原发性或复发性恶性肿瘤方面显示出疗效。