Knockdown of TUG1 by shRNA inhibited renal cell carcinoma formation by miR-299-3p/VEGF axis in vitro and in vivo.

Renal cell carcinoma (RCC) is one of the top ten deadly malignancies in the world. The long non-coding RNA taurine up-regulated gene 1 (TUG1) is a transcript that is up-regulated by taurine. There is ample evidence that TUG1 plays a crucial role in the progression of various cancers. This study aimed to investigate the role of TUG1 in RCC and its underlying molecular mechanisms. In the current study, knockdown of TUG1 by shRNA (sh-TUG1) significantly inhibited proliferation, invasion, migration and EMT processes of ACHN cells and OS-RC-2 cells, and induced apoptosis. Besides, bioinformatics analysis revealed that miR-299-3p is a target of TUG1. TUG1 overexpression (LV-TUG1) significantly inhibited the expression of miR-299-3p, whereas sh-TUG1 showed the opposite effect. Dual luciferase reporter assay further confirmed the targeting relationship between TUG1 and miR-299-3p. In addition, vascular endothelial growth factor (VEGFA) is a target of miR-299-3p. Knockdown of VEGFA (si-VEGFA) significantly inhibited the proliferation and motility of ACHN cells, and induced apoptosis. RT-qPCR results showed that sh-TUG1 similarly inhibited VEGFA expression. Further functional analysis indicated that sh-TUG1 inhibited tumorigenesis by down-regulating VEGFA levels. However, LV-TUG1 showed the opposite effects. Furthermore, animal experiments have shown that sh-TUG1 inhibited tumor growth and metastasis and induces apoptosis in vivo. These results indicate that sh-TUG1 inhibited renal cell carcinoma formation by miR-299-3p/VEGF axis in vitro and in vivo. Taken together, all of these results reveal a novel mechanism of TUG1 in RCC tumorigenesis, suggesting that targeted drugs for TUG1 provides a new direction for the treatment of RCC.

Li Y ，Zheng D ，Pan L ，Dai Y ，Cai S ，Zhao L ，Zhu H ... -  《-》

Taurine up-regulated 1 accelerates tumorigenesis of colon cancer by regulating miR-26a-5p/MMP14/p38 MAPK/Hsp27 axis in vitro and in vivo.

The purpose of this study was to investigate the role of long non-coding RNA taurine-upregulated gene 1 (TUG1) in colon cancer (Cc) and related molecular mechanisms. RT-qPCR, Western blot and immunohistochemistry were used to detect the expression of related proteins. BrdU and Transwell assays were used to detect cell proliferation and invasion, respectively. Immunofluorescence was used to detect the expression of Vimentin. TUG1 expression was up-regulated in CaCO-2, SW620 and HT-29 cells, while miR-26a-5p was down-regulated. Bioinformatics analysis showed that miR-26a-5p was the target of TUG1, and the targeting relationship was further confirmed by dual-luciferase report analysis. Besides, matrix metalloproteinases-14 (MMP-14) was a target of mir-26a-5p. Knockdown of TUG1 by shRNA (sh-TUG1) inhibited MMP-14 expression. Functional analysis showed that sh-TUG1 significantly inhibited Cc cell proliferation, invasion and epithelial-mesenchymal transformation (EMT). Notably, miR-26a-5p inhibitor reversed the promotion of Cc caused by sh-TUG1. Mechanically, the overexpression of TUG1 significantly up-regulated the levels of MMP-14, VEGF, p-p38 mitogen-activated protein kinase (p-p38 MAPK) and p-HSP27 (heat shock protein 27), and promoted the proliferation, invasion and EMT of Cc cells. However, MAPK pathway inhibitor SB203580 has shown the opposite effect. Additionally, animal studies have shown that sh-TUG1 inhibited tumor growth and motility in vivo in the same way. This study demonstrated that TUG1 accelerates the development of colon cancer by regulating miR-26a-5p/MMP14/p38 MAPK/Hsp27 axis in vitro and in vivo. Therefore, TUG1 provides a new direction for the treatment of Cc.

Tian L ，Zhao ZF ，Xie L ，Zhu JP ... -  《-》

Long Non-Coding RNA TUG1 Promotes Proliferation and Inhibits Apoptosis of Osteosarcoma Cells by Sponging miR-132-3p and Upregulating SOX4 Expression.

Li G ，Liu K ，Du X 《-》

LncRNA TUG1 promotes cell proliferation and suppresses apoptosis in osteosarcoma by regulating miR-212-3p/FOXA1 axis.

LncRNA taurine upregulated gene 1 (TUG1) was reported to act as a possible oncogene in osteosarcoma (OS) development. However, the underlying molecular basis of TUG1 involved in the progression of OS remains to be thoroughly investigated. The expressions of TUG1 and miR-212-3p in OS tissues and cells were examined by RT-qPCR. Cell proliferation, apoptosis, caspase-3 activity, protein levels of BCL2, Bax, and forkhead box A1 (FOXA1) were detected by colony formation assay, MTT assay, flow cytometry analysis, caspase-3 activity assay, and western blot. Luciferase reporter assay, RNA immunoprecipitation (RIP) assay, and RT-qPCR were used to explore the interaction between TUG1, FOXA1 and miR-212-3p. Tumor xenograft mouse model was used to confirm the biological role of TUG in OS in vivo. Elevated TUG1 and FOXA1 expression and reduced miR-212-3p expression were observed in OS tissues and cells. TUG1 knockdown suppressed OS cell proliferation and promoted apoptosis. TUG1 functioned as a ceRNA of miR-212-3p and suppressed miR-212-3p expression. miR-212-3p inhibition reversed the effect of TUG1 knockdown on OS cell proliferation and apoptosis. In addition, FOXA1 was identified as a target of miR-212-3p and TUG1 functioned as a ceRNA to upregulate FOXA1 by sponging miR-212-3p in OS cells. FOXA1 up-regulation abolished the effects of miR-212-3p on OS cell proliferation and apoptosis. TUG1 promoted OS cell proliferation and suppressed apoptosis by regulating the miR-212-3p/FOXA1 axis. Therefore, TUG1/miR-212-3p/FOXA1 axis may be a promising therapeutic target in OS treatment.

Xie C ，Chen B ，Wu B ，Guo J ，Cao Y ... -  《-》

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

MicroRNA-142-3p (miR-142-3p) is dysregulated in many malignancies and may function as a tumor suppressor or oncogene in tumorigenesis and tumor development. However, few studies have investigated the clinical significance and biological function of miR-142-3p in hepatocellular carcinoma (HCC). The expression levels of taurine upregulated gene 1 (TUG1), miR-142-3p, and zinc finger E-box-binding homeobox 1 (ZEB1) were evaluated in HCC tissues and cell lines by quantitative real-time PCR. MTT and colony formation assays were used to detect cell proliferation ability, transwell assays were used to assess cell migration and invasion, and luciferase reporter assays were used to examine the interaction between the long noncoding RNA TUG1 and miR-142-3p. Tumor formation was evaluated through in vivo experiments. miR-142-3p was significantly downregulated in HCC tissues, but TUG1 was upregulated in HCC tissues. Knockdown of TUG1 and upregulation of miR-142-3p inhibited cell proliferation, cell migration, cell invasion, and the epithelial-mesenchymal transition (EMT). miR-142-3p was found to be a prognostic factor of HCC, and the mechanism by which TUG1 upregulated ZEB1 was via direct binding to miR-142-3p. In vivo assays showed that TUG1 knockdown suppressed cell proliferation and the EMT in nude mice. The results of this study suggest that the TUG1/miR-142-3p/ ZEB1 axis contributes to the formation of malignant behaviors in HCC.

He C ，Liu Z ，Jin L ，Zhang F ，Peng X ，Xiao Y ，Wang X ，Lyu Q ，Cai X ... -  《-》