Long Noncoding RNA Taurine-Upregulated Gene 1 Promotes Cell Proliferation and Invasion in Gastric Cancer via Negatively Modulating miRNA-145-5p

Abstract

Long noncoding RNA (lncRNA) taurine-upregulated gene 1 (TUG1) is involved in the development and carcinogenesis of various tumors, suggesting the diagnostic potential of TUG1 in these cancers. However, the exact role of TUG1 and its underlying mechanism in gastric cancer (GC) remain unknown. In this study, the expression of TUG1 and miR-145-5p in GC cell lines and nonmalignant gastric epithelial cell lines was detected by qRT-PCR. BGC-823 and SGC-7901 cells were transfected with si-TUG1, pcDNA 3.1-TUG1, miR-145-5p mimics, or matched controls. The biological function of TUG1 and miR-145-5p in GC cell proliferation and invasion in vitro and tumor growth in vivo was investigated by MTT assay, Transwell invasion assay, and tumor xenograft experiments. The regulating relationship between TUG1 and miR-145-5 was confirmed by luciferase reporter assay. The results showed that TUG1 was significantly overexpressed and miR-145-5p was dramatically downregulated in GC cell lines. TUG1 knockdown strikingly inhibited cell proliferation and invasion in vitro and markedly suppressed tumor growth in vivo. Furthermore, TUG1 could directly bind to miR-145-5p and repress miR-145-5p expression. TUG1 overexpression significantly relieved the inhibition on GC cell proliferation and invasion in vitro and tumor growth in vivo, mediated by miR-145-5p overexpression. In conclusion, TUG1 promotes cell proliferation and invasion in GC via negatively modulating miRNA-145-5p, which undoubtedly contributes to understanding the mechanism of GC occurrence and development.

Long non‐coding RNA MIF‐AS1 promotes gastric cancer cell proliferation and reduces apoptosis to upregulate NDUFA4

“…Liu et al showed the tumor‐promoting role of HOTAIR in gastric cancer progression through positively regulating HER2 expression by sponging miR‐331‐3p. In addition, expression of several miRNAs, including miR‐675, miR‐145‐5p, miR‐152, miR‐145, miR‐23b‐3p, and miR‐335‐5p, are significantly dysregulated by lncRNAs and then change the expression of target mRNAs in gastric cancer.…”

“…Liu et al 32 showed the tumor-promoting role of HOTAIR in gastric cancer progression through positively regulating HER2 expression by sponging miR-331-3p. In addition,expression of several miRNAs, including miR-675,33 miR-145-5p,34…”

lncRNA TUG1-Mediated Mir-142-3p Downregulation Contributes to Metastasis and the Epithelial-to-Mesenchymal Transition of Hepatocellular Carcinoma by Targeting ZEB1

“…In a ceRNA model, lncRNA release or upregulate target mRNA of miRNAs by competitively binding with the same miRNAs Zhang et al [27][28][29][30][31]. TUG1 participates in the progression and development of multiple tumors by acting as a ceRNA Zhang et al [22,24,26,[32][33][34][35][36]. To determine whether TUG1 acts as a ceRNA in HCC, we applied bioinformatics analysis (http://starbase.sysu.edu.…”

“…The lncRNA taurine upregulated gene 1 (TUG1) plays a role in the progression of several human cancers by interacting with miRNAs Wang et al [22][23][24]. For example, TUG1 accelerates the malignancy of pancreatic cancer through sponging miR-382 Zhao et al [25], mediates methotrexate resistance in colorectal cancer (CRC) by interacting with miR-186 Li et al [26], acts as an oncogene in osteosarcoma by binding with miR-335 Wang et al [22], and improves gastric cancer progression through sponging miR-145-5p Ren et al [24]. Thus, this study aimed to clarify the interaction between TUG1 and miR-142-3p in HCC.…”

World Workshop on Oral Medicine VII: Functional pathways involving differentially expressed lncRNAs in oral squamous cell carcinoma

“…In vitro, knock‐down of TUG1 induced cell apoptosis and suppressed both cell proliferation and invasion. Studies investigating tumours from other anatomical sites showed that TUG1 can act as a miR‐26a sponge to regulate human glioma cell proliferation (Li, An, Zhang, & Ma, ); it directly binds miR‐145‐5p in gastric (Ren, Li, Li, Zhang, & Han, ) and in bladder cancer cells exerting a double‐negative feedback loop between TUG1 and miR‐145 (Tan, Qiu, Li, & Liang, ). Nevertheless, we do not have data from in vitro studies addressing TSCC/OSCC.…”