Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX 75390, USA.
Quantitative Biomedical Research Center, Department of Population & Data Sciences, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
J Cell Sci. 2022 Oct 15;135(20). doi: 10.1242/jcs.260028. Epub 2022 Oct 27.
The ligand-activated transcription factor aryl hydrocarbon receptor (AHR) regulates cellular detoxification, proliferation and immune evasion in a range of cell types and tissues, including cancer cells. In this study, we used RNA-sequencing to identify the signature of the AHR target genes regulated by the pollutant 2,3,7,8-tetrachlorodibenzodioxin (TCDD) and the endogenous ligand kynurenine (Kyn), a tryptophan-derived metabolite. This approach identified a signature of six genes (CYP1A1, ALDH1A3, ABCG2, ADGRF1 and SCIN) as commonly activated by endogenous or exogenous ligands of AHR in multiple colon cancer cell lines. Among these, the actin-severing protein scinderin (SCIN) was necessary for cell proliferation; SCIN downregulation limited cell proliferation and its expression increased it. SCIN expression was elevated in a subset of colon cancer patient samples, which also contained elevated β-catenin levels. Remarkably, SCIN expression promoted nuclear translocation of β-catenin and activates the WNT pathway. Our study identifies a new mechanism for adhesion-mediated signaling in which SCIN, likely via its ability to alter the actin cytoskeleton, facilitates the nuclear translocation of β-catenin. This article has an associated First Person interview with the first authors of the paper.
配体激活的转录因子芳香烃受体 (AHR) 在包括癌细胞在内的多种细胞类型和组织中调节细胞解毒、增殖和免疫逃逸。在这项研究中,我们使用 RNA 测序来鉴定受污染物 2,3,7,8-四氯二苯并二恶英 (TCDD) 和内源性配体犬尿氨酸 (Kyn) 调节的 AHR 靶基因的特征,犬尿氨酸是一种色氨酸衍生的代谢物。这种方法确定了六个基因 (CYP1A1、ALDH1A3、ABCG2、ADGRF1 和 SCIN) 的特征,这些基因通常被 AHR 的内源性或外源性配体在多种结肠癌细胞系中共同激活。在这些基因中,肌动蛋白切割蛋白 scinderin (SCIN) 是细胞增殖所必需的;SCIN 的下调限制了细胞增殖,而其表达增加了细胞增殖。在一部分结肠癌患者样本中,SCIN 的表达升高,这些样本还含有高水平的β-连环蛋白。值得注意的是,SCIN 的表达促进了β-连环蛋白的核易位,并激活了 WNT 通路。我们的研究确定了一种新的黏附介导信号转导机制,其中 SCIN 可能通过改变肌动蛋白细胞骨架的能力,促进β-连环蛋白的核易位。本文附有对该论文第一作者的第一人称采访。