United Graduate School of Drug Discovery and Medical Information Sciences, Gifu University, 1-1 Yanagido, Gifu 501-1193, Japan.
Department of Anatomy and Biology, Osaka Medical College, 2-7 Daigaku-machi, Takatsuki, Osaka 596-8686, Japan.
Cancer Lett. 2015 Apr 28;360(1):28-38. doi: 10.1016/j.canlet.2015.01.039. Epub 2015 Jan 30.
The fusion gene bcr-abl develops chronic myeloid leukemia (CML), and stimulates PI3K/Akt/mTOR signaling, leading to impaired autophagy. PI3K/Akt/mTOR signaling also plays an important role in cell metabolism. The Warburg effect is a well-recognized hallmark of cancer energy metabolism, and is regulated by the mTOR/c-Myc/hnRNP/PKM signaling cascade. To develop a new strategy for the treatment of CML, we investigated the associations among bcr-abl, the cascade related to cancer energy metabolism, and autophagy induced by a fatty-acid derivative that we had previously reported as being an autophagy inducer. Here we report that a fatty-acid derivative, AIC-47, induced transcriptional repression of the bcr-abl gene and modulated the expression profile of PKM isoforms, resulting in autophagic cell death. We show that c-Myc functioned as a transcriptional activator of bcr-abl, and regulated the hnRNP/PKM cascade. AIC-47, acting through the PPARγ/β-catenin pathway, induced down-regulation of c-Myc, leading to the disruption of the bcr-abl/mTOR/hnRNP signaling pathway, and switching of the expression of PKM2 to PKM1. This switching caused autophagic cell death through an increase in the ROS level. Our findings suggest that AIC-47 induced autophagic cell death through the PPARγ/β-catenin/bcr-abl/mTOR/hnRNP/PKM cascade.
bcr-abl 融合基因导致慢性髓系白血病(CML),并激活 PI3K/Akt/mTOR 信号通路,导致自噬受损。PI3K/Akt/mTOR 信号通路在细胞代谢中也起着重要作用。Warburg 效应是癌症能量代谢的一个公认特征,受 mTOR/c-Myc/hnRNP/PKM 信号级联调控。为了开发治疗 CML 的新策略,我们研究了 bcr-abl 与癌症能量代谢相关级联以及我们之前报道的脂肪酸衍生物诱导的自噬之间的关联,该脂肪酸衍生物被报道为自噬诱导剂。在这里,我们报告说,一种脂肪酸衍生物 AIC-47 诱导 bcr-abl 基因的转录抑制,并调节 PKM 同工型的表达谱,导致自噬细胞死亡。我们表明 c-Myc 作为 bcr-abl 的转录激活剂发挥作用,并调节 hnRNP/PKM 级联。AIC-47 通过 PPARγ/β-catenin 通路作用,诱导 c-Myc 下调,导致 bcr-abl/mTOR/hnRNP 信号通路中断,并切换 PKM2 向 PKM1 的表达。这种转换通过增加 ROS 水平引起自噬细胞死亡。我们的研究结果表明,AIC-47 通过 PPARγ/β-catenin/bcr-abl/mTOR/hnRNP/PKM 级联诱导自噬细胞死亡。