Attenuation of the beta-catenin/TCF4 complex in colorectal cancer cells induces several growth-suppressive microRNAs that target cancer promoting genes
Attenuation of the beta-catenin/TCF4 complex in colorectal cancer cells induces several growth-suppressive microRNAs that target cancer promoting genes
复制标题
DOI：
10.1038/onc.2011.453
复制
发表时间：
2012-05-01
期刊：
影响因子：
8
通讯作者：
Andersen, C. L.
中科院分区：
文献类型：
--
作者：
Schepeler, T.;Holm, A.;Andersen, C. L.
Wnt 信号通路的异常激活与大多数结直肠癌 (CRC) 的形成有关。尽管对 Wnt 调节的蛋白质编码基因已有详细的了解，但对非编码 RNA 的可能参与却知之甚少。在这里，我们使用 TaqMan 阵列 MicroRNA 卡，能够检测 664 种独特的人类 microRNA (miRNA)，来描述 DLD1 CRC 细胞中 β-连环蛋白/TCF4 活性破坏后 miRNA 转录组的变化。根据表达微阵列和 ChIP 芯片数据推断，大多数 miRNA 的反应似乎独立于宿主基因调控和近端 TCF4 染色质占据。相对于正常邻近粘膜 (n = 34)，在两个独立系列的人类原发性 CRC (n = 76) 中，由体外 Wnt 信号传导诱导的 miRNA 模块下调。其中几种 miRNA（miR-145、miR-126、miR-30e-3p 和 miR-139-5p）在异位表达时可显着抑制体外 CRC 细胞生长。通过使用蛋白质组学和表达微阵列的综合方法，我们发现许多 mRNA 和蛋白质受到异位 miR-30e-3p 水平的影响。这包括 HELZ 和 PIK3C2A，它们被几个 miRNA 结合位点直接抑制，荧光素酶报告基因检测结合突变分析证实了这一点。最后，小干扰 RNA 介导的 PIK3C2A 下调（而非 HELZ）本身足以限制 CRC 细胞生长。总的来说，我们的研究表明，CRC 细胞中 Wnt 信号传导强制减弱导致多种 miRNA 上调，其中一些 miRNA 抑制细胞生长，同时抑制多种生长刺激癌症相关基因。癌基因 (2012) 31, 2750-2760; doi：10.1038/onc.2011.453； 2011 年 10 月 3 日在线发布
Aberrant activation of the Wnt signaling pathway is causally involved in the formation of most colorectal cancers (CRCs). Although detailed knowledge exists regarding Wnt-regulated protein-coding genes, much less is known about the possible involvement of non-coding RNAs. Here we used TaqMan Array MicroRNA Cards, capable of detecting 664 unique human microRNAs (miRNAs), to describe changes of the miRNA transcriptome following disruption of beta-catenin/TCF4 activity in DLD1 CRC cells. Most miRNAs appeared to respond independent of host gene regulation and proximal TCF4 chromatin occupancy as inferred from expression microarray and ChIP-chip data. A module of miRNAs induced by abrogated Wnt signaling in vitro was downregulated in two independent series of human primary CRCs (n = 76) relative to normal adjacent mucosa (n = 34). Several of these miRNAs (miR-145, miR-126, miR-30e-3p and miR-139-5p) markedly inhibited CRC cell growth in vitro when ectopically expressed. By using an integrative approach of proteomics and expression microarrays, we found numerous mRNAs and proteins to be affected by ectopic miR-30e-3p levels. This included HELZ and PIK3C2A that were directly repressed by several miRNA binding sites as confirmed by luciferase reporter assays in combination with mutational analyses. Finally, small interfering RNA-mediated downregulation of PIK3C2A, but not HELZ, was sufficient on its own to restrict CRC cell growth. Collectively, our study demonstrates that multiple miRNAs are upregulated as a consequence of forced attenuation of Wnt signaling in CRC cells, and some of these miRNAs inhibit cell growth with concomitant suppression of several growth-stimulatory cancer-related genes. Oncogene (2012) 31, 2750-2760; doi: 10.1038/onc.2011.453; published online 3 October 2011