Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, North Carolina 27710, USA.
Cancer Res. 2010 Nov 15;70(22):9298-308. doi: 10.1158/0008-5472.CAN-10-0226. Epub 2010 Sep 24.
Elevated expression of the orphan nuclear receptor estrogen-related receptor α (ERRα) has been associated with a negative outcome in several cancers, although the mechanism(s) by which this receptor influences the pathophysiology of this disease and how its activity is regulated remain unknown. Using a chemical biology approach, it was determined that compounds, previously shown to inhibit canonical Wnt signaling, also inhibited the transcriptional activity of ERRα. The significance of this association was revealed in a series of biochemical and genetic experiments that show that (a) ERRα, β-catenin (β-cat), and lymphoid enhancer-binding factor-1 form macromolecular complexes in cells, (b) ERRα transcriptional activity is enhanced by β-cat expression and vice versa, and (c) there is a high level of overlap among genes previously shown to be regulated by ERRα or β-cat. Furthermore, silencing of ERRα and β-cat expression individually or together dramatically reduced the migratory capacity of breast, prostate, and colon cancer cells in vitro. This increased migration could be attributed to the ERRα/β-cat-dependent induction of WNT11. Specifically, using (a) conditioned medium from cells overexpressing recombinant WNT11 or (b) WNT11 neutralizing antibodies, we were able to show that this protein was the key mediator of the promigratory activities of ERRα/β-cat. Together, these data provide evidence for an autocrine regulatory loop involving transcriptional upregulation of WNT11 by ERRα and β-cat that influences the migratory capacity of cancer cells.
孤儿核受体雌激素相关受体 α (ERRα) 的表达升高与几种癌症的不良预后相关,尽管该受体影响这种疾病的病理生理学的机制以及其活性如何被调节仍不清楚。使用化学生物学方法,确定了先前显示抑制经典 Wnt 信号的化合物也抑制 ERRα 的转录活性。一系列生化和遗传实验揭示了这种关联的重要性,这些实验表明:(a) ERRα、β-连环蛋白 (β-cat) 和淋巴增强结合因子-1 在细胞中形成大分子复合物,(b) ERRα 的转录活性通过β-cat 的表达增强,反之亦然,以及 (c) 以前显示受 ERRα 或 β-cat 调节的基因之间存在高度重叠。此外,单独或联合沉默 ERRα 和 β-cat 的表达显著降低了体外乳腺癌、前列腺癌和结肠癌细胞的迁移能力。这种迁移增加可以归因于 ERRα/β-cat 依赖性诱导的 WNT11。具体而言,使用(a)过表达重组 WNT11 的细胞的条件培养基或(b)WNT11 中和抗体,我们能够表明这种蛋白是 ERRα/β-cat 促进迁移活性的关键介质。总之,这些数据提供了证据,证明涉及 ERRα 和 β-cat 对 WNT11 的转录上调的自分泌调节环影响癌细胞的迁移能力。