Liu Zhili, Chen Zhenyao, Fan Ruihua, Jiang Bin, Chen Xin, Chen Qinnan, Nie Fengqi, Lu Kaihua, Sun Ming
Department of Oncology, The Affiliated Jiangyin Hospital of Southeast University Medical College, Wuxi, People's Republic of China.
Department of Oncology, Second Affiliated Hospital, Nanjing Medical University, Nanjing, 210011, People's Republic of China.
Mol Cancer. 2017 Apr 26;16(1):82. doi: 10.1186/s12943-017-0651-6.
Long noncoding RNAs (lncRNAs) have emerged as critical regulators in a variety of human cancers, including gastric cancer (GC). However, the function and mechanisms responsible for these molecules in GC are not fully understood. In our previous study, we found that GC associated lncRNA HOXA11-AS is significantly upregulated in GC tissues. Over-expressed HOXA11-AS promotes GC cells proliferation and invasion through scaffolding the chromatin modification factors PRC2, LSD1 and DNMT1.
HOXA11-AS expression levels in GC cells was detected by quantitative real-time PCR (qPCR). HOXA11-AS siRNAs and overexpression vector were transfected into GC cells to down-regulate or up-regulate HOXA11-AS expression. In vitro and in vivo assays were performed to investigate the functional role of HOXA11-AS in GC cells cell cycle progression, invasion and metastasis. RIP and ChIP assays were used to determine the mechanism of HOXA11-AS's regulation of underlying targets.
We found that knockdown of HOXA11-AS induced GC cells G0/G1 phase arrest and suppressed GC cells migration, invasion and metastasis in vivo. Moreover, mechanistic investigation showed that HOXA11-AS could interact with WDR5 and promote β-catenin transcription, bind with EZH2 and repress P21 transcription, and induce KLF2 mRNA degradation via interacting with STAU1.
Taken together, these findings show that HOXA11-AS not only could promote GC cells migration and invasion in vitro, but also promotes GC cells metastasis in vivo, at least in part, by regulating β-catenin and KLF2.
长链非编码RNA(lncRNAs)已成为包括胃癌(GC)在内的多种人类癌症中的关键调节因子。然而,这些分子在胃癌中的功能和机制尚未完全明确。在我们之前的研究中,我们发现与胃癌相关的lncRNA HOXA11-AS在胃癌组织中显著上调。过表达的HOXA11-AS通过结合染色质修饰因子PRC2、LSD1和DNMT1促进胃癌细胞的增殖和侵袭。
通过定量实时PCR(qPCR)检测胃癌细胞中HOXA11-AS的表达水平。将HOXA11-AS的小干扰RNA(siRNAs)和过表达载体转染到胃癌细胞中,以下调或上调HOXA11-AS的表达。进行体外和体内实验,以研究HOXA11-AS在胃癌细胞周期进程、侵袭和转移中的功能作用。采用RNA免疫沉淀(RIP)和染色质免疫沉淀(ChIP)实验来确定HOXA11-AS对潜在靶标的调控机制。
我们发现敲低HOXA11-AS可诱导胃癌细胞停滞于G0/G1期,并在体内抑制胃癌细胞的迁移、侵袭和转移。此外,机制研究表明,HOXA11-AS可与WD重复结构域5(WDR5)相互作用并促进β-连环蛋白转录,与EZH2结合并抑制P21转录,并通过与Staufen 1(STAU1)相互作用诱导KLF2信使核糖核酸(mRNA)降解。
综上所述,这些发现表明HOXA11-AS不仅可在体外促进胃癌细胞的迁移和侵袭,还可在体内促进胃癌细胞转移,至少部分是通过调节β-连环蛋白和KLF2实现的。