Long non-coding RNA NNT-AS1 sponges miR-424/E2F1 to promote the tumorigenesis and cell cycle progression of gastric cancer.

Long non-coding RNAs (lncRNAs) have been illustrated to function as important regulators in carcinogenesis and cancer progression. However, the roles of lncRNA NNT-AS1 in gastric cancer remain unclear. In the present study, we investigate the biological role of NNT-AS1 in gastric cancer tumorigenesis. Results revealed that NNT-AS1 expression level was significantly up-regulated in GC tissue and cell lines compared with adjacent normal tissue and normal cell lines. The ectopic overexpression of NNT-AS1 indicated the poor prognosis of GC patients. In vitro experiments validated that NNT-AS1 knockdown suppressed the proliferation and invasion ability and induced the GC cell cycle progression arrest at G0/G1 phase. In vivo xenograft assay, NNT-AS1 silencing decreased the tumour growth of GC cells. Bioinformatics online program predicted that miR-424 targeted the 3'-UTR of NNT-AS1. Luciferase reporter assay, RNA-immunoprecipitation (RIP) and RNA pull-down assay validated the molecular binding within NNT-AS1 and miR-424, therefore jointly forming the RNA-induced silencing complex (RISC). Moreover, E2F1 was verified to act as the target gene of NNT-AS1/miR-424, indicating the NNT-AS1/miR-424/E2F1 axis. In conclusion, our study indicates that NNT-AS1 sponges miR-424/E2F1 to facilitate GC tumorigenesis and cycle progress, revealing the oncogenic role of NNT-AS1 for GC.

Chen B ，Zhao Q ，Guan L ，Lv H ，Bie L ，Huang J ，Chen XB ... -  《-》

E2F1-Induced Overexpression of Long Noncoding RNA SBF2-AS1 Promotes Non-Small-Cell Lung Cancer Metastasis Through Regulating miR-362-3p/GRB2 Axis.

Wang A ，Wang J 《-》

Down-regulated lncRNA SLC25A5-AS1 facilitates cell growth and inhibits apoptosis via miR-19a-3p/PTEN/PI3K/AKT signalling pathway in gastric cancer.

Mounting evidence has illustrated the vital roles of long non-coding RNAs (lncRNAs in gastric cancer (GC). Nevertheless, the majority of their roles and mechanisms in GC are still largely unknown. In this study, we investigate the roles of lncRNA SLC25A5-AS1 on tumourigenesis and explore its potential mechanisms in GC. The results showed that the expressions of SLC25A5-AS1 in GC were significantly lower than that of adjacent normal tissues, which were significantly associated with tumour size, TNM stage and lymph node metastasis. Moreover, SLC25A5-AS1 could inhibit GC cell proliferation, induce G1/G1 cell cycle arrest and cell apoptosis in vitro, as well as GC growth in vivo. Dual-luciferase reporter assay confirmed the direct interaction between SLC25A5-AS1 and miR-19a-3p, rescue experiment showed that co-transfection miR-19a-3p mimics and pcDNA-SLC25A5-AS1 could partially restore the ability of GC cell proliferation and the inhibition of cell apoptosis. The mechanism analyses further found that SLC25A5-AS1 might act as a competing endogenous RNAs (ceRNA), which was involved in the derepression of PTEN expression, a target gene of miR-19a-3p, and regulate malignant phenotype via PI3K/AKT signalling pathway in GC. Taken together, this study indicated that SLC25A5-AS1 was down-regulated in GC and functioned as a suppressor in the progression of GC. Moreover, it could act as a ceRNA to regulate cellular behaviours via miR-19a-3p/PTEN/PI3K/AKT signalling pathway. Thus, SLC25A5-AS1 might be served as a potential target for cancer therapeutics in GC.

Li X ，Yan X ，Wang F ，Yang Q ，Luo X ，Kong J ，Ju S ... -  《-》

Long noncoding RNA NNT-AS1 promotes gastric cancer proliferation and invasion by regulating microRNA-363 expression.

Increasing studies showed that long noncoding RNAs (lncRNAs) had crucial regulatory roles in various tumors, including gastric cancer (GC). Recent studies demonstrated that lncRNA nicotinamide nucleotide transhydrogenase-antisense RNA1 (NNT-AS1) played an important role in several tumors. However, the role and expression of NNT-AS1 in GC progression remain unknown. In our study, we indicated that NNT-AS1 expression was upregulated in GC samples compared with the nontumor tissues. We also showed that NNT-AS1 expression was upregulated in the GC cell lines. Ectopic expression of NNT-AS1 promoted GC cell line HGC-27 cell proliferation, cell cycle progression, and invasion. In addition, we showed that NNT-AS1 acted as a sponge competing endogenous RNA for microRNA-363 (miR-363), which was downregulated in the GC samples and cell lines. miR-363 expression was negatively related with NNT-AS1 expression in GC samples. Upregulated expression of miR-363 suppressed GC cell growth, cycle, and invasion. Furthermore, we reported that elevated expression of NNT-AS1 promoted GC cell proliferation, cycle, and invasion partly by suppressing miR-363 expression. These results indicated that lncRNA NNT-AS1 acted as an oncogene in the development of GC partly by inhibiting miR-363 expression.

Wang X ，Ren M ，Li Y ，Hu J ，Lu G ，Ma W ，Guo D ，Lu X ，He S ... -  《-》

Long non-coding RNA C5orf66-AS1 promotes cell proliferation in cervical cancer by targeting miR-637/RING1 axis.

Rui X ，Xu Y ，Jiang X ，Ye W ，Huang Y ，Jiang J ... -  《Cell Death & Disease》