Long non-coding RNA NEAT1 promotes colorectal cancer progression by competitively binding miR-34a with SIRT1 and enhancing the Wnt/β-catenin signaling pathway.

In recent years, accumulating evidence has indicated that long non-coding RNAs (lncRNAs) are powerful factors influencing the progression of multiple malignancies. Although a relationship between the lncRNA NEAT1 (nuclear enriched abundant transcript 1) and colorectal cancer has previously been reported, the functional mechanism underlying the involvement of NEAT1 in colorectal cancer remains unknown. In this study, we report that NEAT1 expression is up-regulated in colorectal cancer tissues, which correlates with advanced clinical features, poor overall survival and disease free survival. Up-regulated NEAT1 promotes cell proliferation and metastasis of colorectal cancer both in vitro and in vivo. Moreover, NEAT1 functions as an oncogene influencing cell viability and invasion in part by serving as a competing endogenous RNA (ceRNAs) modulating miRNA-34a expression, leading to subsequent repression of the miR-34a/SIRT1 axis and activation of the Wnt/β-catenin signaling pathway. Taken together, our study demonstrates that the lncRNA NEAT1 may serve as a prognostic biomarker and a potential therapeutic target in colorectal cancer.

Luo Y ，Chen JJ ，Lv Q ，Qin J ，Huang YZ ，Yu MH ，Zhong M ... -  《-》

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

Zhang M ，Weng W ，Zhang Q ，Wu Y ，Ni S ，Tan C ，Xu M ，Sun H ，Liu C ，Wei P ，Du X ... -  《Journal of Hematology & Oncology》

Long non-coding RNA HNF1A-AS1 mediated repression of miR-34a/SIRT1/p53 feedback loop promotes the metastatic progression of colon cancer by functioning as a competing endogenous RNA.

In recent years, accumulating evidence indicates that long noncoding RNAs (lncRNAs) have emerged as powerful influence factors in the progression of multiple malignancies. Dysregulation of lncRNA HNF1A-antisense 1 (HNF1A-AS1) has been reported in many types of human cancers, and studies on HNF1A-AS1 function in cancers revealed that HNF1A-AS1could act as either oncogene or tumor suppressor. Nevertheless, the functional involvement of HNF1A-AS1 in colon cancer remains unknown. In this study, we reported that HNF1A-AS1 was frequently upregulated in colon cancer tissues and associated with poor prognosis. Upregulated HNF1A-AS1 promoted colon cancer cell viability, migration and invasion both in vitro and in vivo. HNF1A-AS1 silencing impaired tumor growth and metastasis in xenograft model assay. Moreover, HNF1A-AS1 functioned as an oncogene in metastasis of colon cancer in part through serving as a competing endogenous RNA to modulate miRNA-34a expression, subsequently with repression of miR-34a/SIRT1/p53 feedback loop and activation of canonical Wnt signaling pathway. Our results demonstrated that HNF1A-AS1 mediated the metastatic progression of colon cancer in part through miR-34a/p53 signaling axis, and established its candidacy as a new prognostic biomarker and a potential novel therapeutic target.

Fang C ，Qiu S ，Sun F ，Li W ，Wang Z ，Yue B ，Wu X ，Yan D ... -  《-》

The Long Non-Coding RNA CRNDE Promotes Colorectal Carcinoma Progression by Competitively Binding miR-217 with TCF7L2 and Enhancing the Wnt/β-Catenin Signaling Pathway.

The long non-coding RNA colorectal neoplasia differentially expressed (CRNDE) contributes to the proliferation and migration of tumors. However, its molecular mechanism underlying gastric cancer remains unknown. In the present study, we investigated whether CRNDE was involved in the development of colorectal cancer via the binding of microRNA (miR)-217 with transcription factor 7-like 2 (TCF7L2) to enhance the Wnt signaling pathway. Quantitative polymerase chain reaction was used to detect CRNDE, miR-217 and TCF7L2 in colorectal cancer tissues and cells. The CCK-8 assay, wound healing assay, and Transwell assay were used to detect cell proliferation, migration and invasion, respectively. Western blotting and luciferase activity assays were used to identify CRNDE and TCF7L2 as one of the direct targets of miR-217. The activity of the Wnt/β-catenin signaling pathway was analyzed by the TOPflash assay, and the subcellular localization of β-catenin and TCF7L2 was analyzed by western blotting and confocal microscopy. In this study, we found that high expression of CRNDE is negatively correlated with low expression of miR-217 in colorectal cancer tissue and colorectal cancer cells. The dual luciferase reporter analysis showed that miR-217 is bound to CRNDE and TCF7L2 and negatively regulate their expression. CRNDE down-regulation inhibited the cell proliferation, migration and invasion in vitro and in vivo and the inhibitions were both completely blocked after miR-217 inhibition or TCF7L2 overexpression. Finally, TOPflash analysis showed that the activity of Wnt/β-catenin signaling is inhibited by CRNDE down-regulation and rescued by TCF7L2 over-expression. Consistently immunostaining and western blotting analysis showed that the expression of b-catenin and TCF7L2 in the nucleus was significantly decreased by CRNDE down-regulation and was rescued by TCF7L2 over-expression. The present study suggest that CRNDE involves in the cell proliferation, migration and invasion of colorectal cancer cells via increasing the expression of TCF7L2 and activity of Wnt/β-catenin signaling through binding miR-217 competitively.

Yu B ，Ye X ，Du Q ，Zhu B ，Zhai Q ，Li XX ... -  《-》

The Long Noncoding RNA NEAT1 Targets miR-34a-5p and Drives Nasopharyngeal Carcinoma Progression via Wnt/β-Catenin Signaling.

Long noncoding RNA nuclear paraspeckle assembly transcript 1 (NEAT1) has been deemed an oncogene in many human cancers. However, the underlying mechanism of NEAT1 in nasopharyngeal carcinoma (NPC) progression remains largely unclear. Quantitative real-time PCR assay was performed to assess the expression of NEAT1 and miR-34a-5p in NPC tissues and cells. Western blot analysis was used to observe cell epithelial to mesenchymal transition (EMT) and the activation of Wnt/β-catenin signaling in 5-8F cells. MiRNA directly interacting with NEAT1 were verified by dual-luciferase reporter assay and RNA immunoprecipitation. Cell proliferation ability was determined by CCK-8 assay, and cell migration and invasion capacities were assessed by transwell assays. An animal model was used to investigate the regulatory effect of NEAT1 on tumor growth in vivo. Our data revealed that NEAT1 is upregulated, while miR-34a-5p is downregulated in NPC tissues and cell lines. NEAT1 knockdown repressed tumor growth in vitro and in vivo. Additionally, we discovered that NEAT1 directly binds to miR-34a-5p and suppresses miR-34a-5p expression. Moreover, NEAT1 knockdown exerted suppression effects on cell proliferation, migration, invasion, and EMT by miR-34a-5p. NEAT1 knockdown blocked Wnt/β-catenin signaling via miR-34a-5p. Our study demonstrated that NEAT1 targets miR-34a-5p at least partly to drive NPC progression by regulating Wnt/β-catenin signaling, suggesting a potential therapeutic target for NPC.

Ji Y ，Wang M ，Li X ，Cui F ... -  《-》