Department of Urology, Changhai Hospital, Naval Medical University, Shanghai, China.
Department of Urology, Changzheng Hospital, Naval Medical University, Shanghai, China.
Cancer Sci. 2022 Feb;113(2):446-458. doi: 10.1111/cas.15212. Epub 2021 Dec 16.
Growing evidence supports that N6-methyladenosine (m6A) modification acts as a critical regulator involved in tumorigenesis at the mRNA level. However, the role of m6A modification at the noncoding RNA level remains largely unknown. We found that methyltransferase-like 14 (METTL14) was significantly downregulated in renal cell carcinoma (RCC) tissues (n = 580). Gain-of-function and loss-of-function experiments revealed that METTL14 attenuated the proliferation and migration ability of RCC cells in vivo and in vitro. The methylated RNA immunoprecipitation experiments identified that METTL14 decreased the expression of long noncoding RNA nuclear enriched abundant transcript 1_1 (NEAT1_1) in an m6A-dependent manner. Mechanistically, RNA pull-down assay and RNA immunoprecipitation identified NEAT1_1 directly bound to m6A reader YTH N6-methyladenosine RNA binding protein 2 (YTHDF2). Notably, YTHDF2 accelerated the degradation of NEAT1_1 by selectively recognizing METTL14-mediated m6A marks on NEAT1_1. Multivariate analysis suggested that METTL14 downregulation was associated with malignant characteristics and predicted poor prognosis in RCC patients. In conclusion, our results uncover a newly identified METTL14-YTHDF2-NEAT1_1 signaling axis, which facilitates RCC growth and metastasis and provides fresh insight into RCC therapy.
越来越多的证据表明,N6-甲基腺苷(m6A)修饰作为一种关键的调节因子,在mRNA 水平上参与肿瘤发生。然而,m6A 修饰在非编码 RNA 水平上的作用在很大程度上仍然未知。我们发现,甲基转移酶样蛋白 14(METTL14)在肾细胞癌(RCC)组织中显著下调(n=580)。功能获得和功能丧失实验表明,METTL14 在体内和体外减弱了 RCC 细胞的增殖和迁移能力。甲基化 RNA 免疫沉淀实验表明,METTL14 以 m6A 依赖的方式降低了长非编码 RNA 核富集丰富转录物 1_1(NEAT1_1)的表达。在机制上,RNA 下拉测定和 RNA 免疫沉淀鉴定出 NEAT1_1 直接与 m6A 阅读器 YTH N6-甲基腺苷 RNA 结合蛋白 2(YTHDF2)结合。值得注意的是,YTHDF2 通过选择性识别 NEAT1_1 上 METTL14 介导的 m6A 标记,加速了 NEAT1_1 的降解。多变量分析表明,METTL14 的下调与恶性特征有关,并预测 RCC 患者的预后不良。总之,我们的研究结果揭示了一个新的 METTL14-YTHDF2-NEAT1_1 信号轴,该信号轴促进了 RCC 的生长和转移,并为 RCC 的治疗提供了新的见解。