NF-κB 激活的 SPRY4-IT1 通过 Staufen1 介导的 mRNA 降解下调 TCEB1 mRNA 促进癌细胞转移。
NF-κB-activated SPRY4-IT1 promotes cancer cell metastasis by downregulating TCEB1 mRNA via Staufen1-mediated mRNA decay.
机构信息
Department of Pharmacology, School of Pharmacy, China Medical University, No.77 Puhe Road, Shenyang North New Area, Shenyang City, 110122, Liaoning, China.
Liaoning Key Laboratory of molecular targeted anti-tumor drug development and evaluation, China Medical University No.77 Puhe Road, Shenyang North New Area, Shenyang City, 110122, Liaoning, China.
出版信息
Oncogene. 2021 Jul;40(30):4919-4929. doi: 10.1038/s41388-021-01900-8. Epub 2021 Jun 23.
Previous study demonstrated that most long non-coding RNAs (lncRNAs) function as competing endogenous RNAs or molecular sponges to negatively modulate miRNA and regulate tumor development. However, the molecular mechanisms of lncRNAs in cancer are not fully understood. Our study describes the role of the lncRNA SPRY4 intronic transcript 1 (SPRY4-IT1) in cancer metastasis by mechanisms related to Staufen1 (STAU1)-mediated mRNA decay (SMD). Briefly, we found that, high SPRY4-IT1 expression was associated with aggressiveness and poor outcome in human colorectal, breast and ovarian cancer tissues. In addition, functional assays revealed that SPRY4-IT1 significantly promoted colorectal, breast and ovarian cancer metastasis in vitro and in vivo. Mechanistically, microarray analyses identified several differentially-expressed genes upon SPRY4-IT1 overexpression in HCT 116 colorectal cancer cells. Among them, the 3'-UTR of transcription elongation factor B subunit 1 (TCEB1) mRNA can base-pair with the Alu element in the 3'-UTR of SPRY4-IT1. Moreover, SPRY4-IT1 was found to bind STAU1, promote STAU1 recruitment to the 3'-UTR of TCEB1 mRNA, and affect TCEB1 mRNA stability and expression, resulting in hypoxia-inducible factor 1α (HIF-1α) upregulation, and thereby affecting cancer cell metastasis. In addition, STAU1 depletion abrogated TCEB1 SMD and alleviated the pro-metastatic effect of SPRY4-IT1 overexpression. Significantly, we revealed that SPRY4-IT1 is also transactivated by NF-κB/p65, which activates SPRY4-IT1 to inhibit TCEB1 expression, and subsequently upregulate HIF-1α. In conclusion, our results highlight a novel mechanism of cytoplasmic lncRNA SPRY4-IT1 in which SPRY4-IT1 affecting TCEB1 mRNA stability via STAU1-mediated degradation during cancer metastasis.
先前的研究表明,大多数长非编码 RNA(lncRNA)作为竞争性内源性 RNA 或分子海绵,通过负调控 miRNA 来调节肿瘤的发生和发展。然而,lncRNA 在癌症中的分子机制尚未完全阐明。我们的研究通过涉及 Staufen1(STAU1)介导的 mRNA 降解(SMD)的机制,描述了 lncRNA SPRY4 内含子转录本 1(SPRY4-IT1)在癌症转移中的作用。简而言之,我们发现高 SPRY4-IT1 表达与人类结直肠癌、乳腺癌和卵巢癌组织的侵袭性和不良预后相关。此外,功能分析表明,SPRY4-IT1 显著促进了结直肠、乳腺和卵巢癌细胞在体外和体内的转移。从机制上讲,微阵列分析鉴定出在 HCT 116 结直肠癌细胞中过表达 SPRY4-IT1 后差异表达的几个基因。其中,转录延伸因子 B 亚基 1(TCEB1)mRNA 的 3'-UTR 可以与 SPRY4-IT1 的 3'-UTR 中的 Alu 元件碱基配对。此外,发现 SPRY4-IT1 与 STAU1 结合,促进 STAU1 募集到 TCEB1 mRNA 的 3'-UTR,并影响 TCEB1 mRNA 的稳定性和表达,导致缺氧诱导因子 1α(HIF-1α)上调,从而影响癌细胞的转移。此外,STAU1 的耗竭消除了 TCEB1 的 SMD,并减轻了 SPRY4-IT1 过表达的促转移作用。重要的是,我们揭示了 SPRY4-IT1 也被 NF-κB/p65 反式激活,NF-κB/p65 激活 SPRY4-IT1 抑制 TCEB1 的表达,随后上调 HIF-1α。总之,我们的结果强调了细胞质 lncRNA SPRY4-IT1 在癌症转移过程中通过 STAU1 介导的降解影响 TCEB1 mRNA 稳定性的新机制。