长链非编码 RNA NEAT1 通过与 DDX5 相互作用激活 Wnt/β-catenin 信号通路并促进结直肠癌的进展。

The lncRNA NEAT1 activates Wnt/β-catenin signaling and promotes colorectal cancer progression via interacting with DDX5.

机构信息

Department of Pathology, Fudan University Shanghai Cancer Center, Shanghai, 200032, China.

Department of Pathology, Shanghai Medical College, Fudan University, Shanghai, China.

出版信息

J Hematol Oncol. 2018 Sep 5;11(1):113. doi: 10.1186/s13045-018-0656-7.

BACKGROUND

The long noncoding RNA nuclear-enriched abundant transcript 1 (NEAT1) has been reported to be overexpressed in colorectal cancer (CRC). However, its underlying mechanisms in the progression of CRC have not been well studied.

METHODS

To investigate the clinical significance of NEAT1, we analyzed its expression levels in a publicly available dataset and in 71 CRC samples from Fudan University Shanghai Cancer Center. Functional assays, including the CCK8, EdU, colony formation, wound healing, and Transwell assays, were used to determine the oncogenic role of NEAT1 in human CRC progression. Furthermore, RNA pull-down, mass spectrometry, RNA immunoprecipitation, and Dual-Luciferase Reporter Assays were used to determine the mechanism of NEAT1 in CRC progression. Animal experiments were used to determine the role of NEAT1 in CRC tumorigenicity and metastasis in vivo.

RESULTS

NEAT1 expression was significantly upregulated in CRC tissues compared with its expression in normal tissues. Altered NEAT1 expression led to marked changes in proliferation, migration, and invasion of CRC cells both in vitro and in vivo. Mechanistically, we found that NEAT1 directly bound to the DDX5 protein, regulated its stability, and sequentially activated Wnt signaling. Our study showed that NEAT1 indirectly activated the Wnt/β-catenin signaling pathway via DDX5 and fulfilled its oncogenic functions in a DDX5-mediated manner. Clinically, concomitant NEAT1 and DDX5 protein levels negatively correlated with the overall survival and disease-free survival of CRC patients.

CONCLUSIONS

Our findings indicated that NEAT1 activated Wnt signaling to promote colorectal cancer progression and metastasis. The NEAT1/DDX5/Wnt/β-catenin axis could be a potential therapeutic target of pharmacological strategies.

背景

长链非编码 RNA 核富集丰富转录本 1（NEAT1）在结直肠癌（CRC）中表达上调。然而，其在 CRC 进展中的潜在机制尚未得到充分研究。

方法

为了研究 NEAT1 的临床意义，我们分析了公共可用数据集和复旦大学上海癌症中心 71 例 CRC 样本中的表达水平。使用 CCK8、EdU、集落形成、划痕愈合和 Transwell 测定等功能测定来确定 NEAT1 在人 CRC 进展中的致癌作用。此外，还使用 RNA 下拉、质谱、RNA 免疫沉淀和双荧光素酶报告基因测定来确定 NEAT1 在 CRC 进展中的作用机制。动物实验用于确定 NEAT1 在 CRC 肿瘤发生和体内转移中的作用。

结果

与正常组织相比，CRC 组织中 NEAT1 的表达明显上调。改变 NEAT1 的表达导致 CRC 细胞在体外和体内的增殖、迁移和侵袭发生明显变化。从机制上讲，我们发现 NEAT1 直接与 DDX5 蛋白结合，调节其稳定性，并依次激活 Wnt 信号通路。我们的研究表明，NEAT1 通过 DDX5 间接激活 Wnt/β-catenin 信号通路，并以 DDX5 介导的方式发挥其致癌功能。临床上，NEAT1 和 DDX5 蛋白水平的同时升高与 CRC 患者的总生存期和无病生存期呈负相关。