Gastric Cancer Department, Liaoning Cancer Hospital & Institute (Cancer Hospital of China Medical University), No. 44 Xiaoheyan Road, Dadong District, Shenyang City, 110042, Liaoning Province, People's Republic of China.
Medical Oncology Department of Gastrointestinal Cancer, Liaoning Cancer Hospital & Institute (Cancer Hospital of China Medical University), No. 44 Xiaoheyan Road, Dadong District, Shenyang City, 110042, Liaoning Province, People's Republic of China.
J Physiol Biochem. 2019 Aug;75(3):379-389. doi: 10.1007/s13105-019-00690-8. Epub 2019 Jul 9.
N-Methyladenosine (mA) is the most common posttranscriptional modification of RNA and plays critical roles in cancer pathogenesis. However, the biological function of long noncoding RNA (lncRNA) methylation remains unclear. As a demethylase, ALKBH5 (alkylation repair homolog protein 5) is involved in mediating methylation reversal. The purpose of this study was to investigate lncRNA mA modification and its role in gastric cancer (GC). Bioinformatics predicted interactions of ALKBH5 with lncRNAs. Five methods were employed to assess the function of nuclear paraspeckle assembly transcript 1 (NEAT1), including gene silencing, RT-PCR, separation of nuclear and cytoplasmic fractions, scrape motility assays, and transwell migration assays. Then, mA RNA immunoprecipitation and immunofluorescence were used to detect methylated NEAT1 in GC cells. Rescue assays were performed to define the relationship between NEAT1 and ALKBH5. NEAT1 is a potential binding lncRNA of ALKBH5. NEAT1 was overexpressed in GC cells and tissue. Additional experiments confirmed that knockdown of NEAT1 significantly repressed invasion and metastasis of GC cells. ALKBH5 affected the mA level of NEAT1. The binding of ALKBH5 and NEAT1 influences the expression of EZH2 (a subunit of the polycomb repressive complex) and thus affects GC invasion and metastasis. Our findings indicate a novel mechanism by which ALKBH5 promotes GC invasion and metastasis by demethylating the lncRNA NEAT1. They may be potential therapeutic targets for GC.
N6-甲基腺苷（m6A）是 RNA 最普遍的转录后修饰，在癌症发病机制中发挥关键作用。然而，长链非编码 RNA（lncRNA）甲基化的生物学功能尚不清楚。作为一种去甲基酶，ALKBH5（烷基化修复同源蛋白 5）参与介导甲基化逆转。本研究旨在探讨 lncRNA m6A 修饰及其在胃癌（GC）中的作用。生物信息学预测了 ALKBH5 与 lncRNAs 的相互作用。采用五种方法评估核斑分离转录物 1（NEAT1）的功能，包括基因沉默、RT-PCR、核质分离、划痕运动测定和 Transwell 迁移测定。然后，采用 mA RNA 免疫沉淀和免疫荧光法检测 GC 细胞中甲基化的 NEAT1。进行挽救实验以确定 NEAT1 和 ALKBH5 之间的关系。NEAT1 是 ALKBH5 的潜在结合 lncRNA。NEAT1 在 GC 细胞和组织中过表达。进一步的实验证实，敲低 NEAT1 可显著抑制 GC 细胞的侵袭和转移。ALKBH5 影响 NEAT1 的 mA 水平。ALKBH5 和 NEAT1 的结合影响多梳抑制复合物（PRC）EZH2（一个亚基）的表达，从而影响 GC 的侵袭和转移。我们的研究结果表明，ALKBH5 通过去甲基化 lncRNA NEAT1 促进 GC 侵袭和转移的一种新机制。它们可能是 GC 的潜在治疗靶点。
