Department of Surgery, Hillman Cancer Center, University of Pittsburgh Cancer Institute, Pittsburgh, PA 15232, USA.
Cell Death Differ. 2010 Apr;17(4):666-76. doi: 10.1038/cdd.2009.149. Epub 2009 Oct 16.
Activation of the induced receptor for advanced glycation end products (RAGE) leads to initiation of NF-kappaB and MAP kinase signaling pathways, resulting in propagation and perpetuation of inflammation. RAGE-knockout animals are less susceptible to acute inflammation and carcinogen-induced tumor development. We have reported that most forms of tumor cell death result in release of the RAGE ligand, high-mobility group protein 1 (HMGB1). We now report a novel role for RAGE in the tumor cell response to stress. Targeted knockdown of RAGE in the tumor cell, leads to increased apoptosis, diminished autophagy and decreased tumor cell survival . In contrast, overexpression of RAGE is associated with enhanced autophagy, diminished apoptosis and greater tumor cell viability. RAGE limits apoptosis through a p53-dependent mitochondrial pathway. Moreover, RAGE-sustained autophagy is associated with decreased phosphorylation of mammalian target of rapamycin (mTOR) and increased Beclin-1/VPS34 autophagosome formation. These findings show that the inflammatory receptor, RAGE, has a heretofore unrecognized role in the tumor cell response to stress. Furthermore, these studies establish a direct link between inflammatory mediators in the tumor microenvironment and resistance to programmed cell death. Our data suggest that targeted inhibition of RAGE or its ligands may serve as novel targets to enhance current cancer therapies.
诱导型晚期糖基化终产物受体(RAGE)的激活导致 NF-κB 和 MAP 激酶信号通路的启动,从而导致炎症的传播和持续。RAGE 基因敲除动物对急性炎症和致癌物诱导的肿瘤发展的敏感性降低。我们已经报道,大多数形式的肿瘤细胞死亡都会导致 RAGE 配体,高迁移率族蛋白 1(HMGB1)的释放。我们现在报告 RAGE 在肿瘤细胞对压力的反应中的一个新作用。在肿瘤细胞中靶向敲低 RAGE,会导致细胞凋亡增加、自噬减少和肿瘤细胞存活减少。相比之下,RAGE 的过表达与增强的自噬、减少的细胞凋亡和更高的肿瘤细胞活力有关。RAGE 通过依赖 p53 的线粒体途径限制细胞凋亡。此外,RAGE 持续的自噬与哺乳动物雷帕霉素靶蛋白(mTOR)的磷酸化减少和 Beclin-1/VPS34 自噬体形成增加有关。这些发现表明,炎症受体 RAGE 在肿瘤细胞对压力的反应中具有以前未知的作用。此外,这些研究建立了肿瘤微环境中的炎症介质与对程序性细胞死亡的抗性之间的直接联系。我们的数据表明,靶向抑制 RAGE 或其配体可能成为增强现有癌症治疗的新靶点。