LncRNA TUG1 promotes hepatic lipid accumulation by targeting the miR-29a-3p/SREBP-2/HMGCR axis in MAFLD.

The aim of this study was to investigate the specific role of Taurine up-regulated gene 1 (TUG1) in the development of prostate cancer (PCa), and to explore its underlying mechanism. The serum level of TUG1 in healthy subjects, benign prostatic hyperplasia (BPH) patients and PCa patients was detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The correlation between TUG1 expression and clinical indexes of PCa patients was analyzed. TUG1 expression in PCa cells and human normal prostate cells was determined by qRT-PCR as well. Overexpression or knockdown of TUG1 was achieved by liposomal transfection. Subsequently, the regulatory effects of TUG1 on the proliferative and migratory capacities of DU145 cells were accessed by Cell Counting Kit-8 (CCK-8) assay, colony formation assay and transwell assay, respectively. An online software was used to predict whether RLIM could be regulated by TUG1, which was further verified by qRT-PCR. After RLIM knockdown in DU145 cells, the proliferative and migratory capacities were also determined. Finally, Western blot was conducted to determine relative protein expressions in the TGF-β1/Smad pathway after altering TUG1 expression in DU145 cells. TUG1 was highly expressed in serum samples of PCa patients when compared with healthy subjects and BPH patients. Besides, TUG1 expression in PCa patients with Gleason ≥ 7 was significantly higher than those with Gleason < 7. Meanwhile, TUG1 expression in PCa patients was remarkably higher than that of BPH patients at the PSA grey zone (4-10 ng/mg). ROC curves indicated that TUG1 might be a crucial hallmark to distinguish PCa patients from BPH patients and healthy subjects. The overexpression of TUG1 markedly promoted the proliferative and migratory capacities of DU145 cells. However, knockdown of TUG1 obtained the opposite results. QRT-PCR confirmed that TUG1 was positively correlated with RLIM at the mRNA level. RLIM knockdown significantly inhibited the proliferative and migratory capacities of DU145 cells. Furthermore, knockdown of TUG1 in DU145 cells markedly down-regulated TGF-β1 and p-Smad2, whereas up-regulated p-Smad7. TUG1 is highly expressed in peripheral blood of PCa patients, which can serve as a potential diagnostic marker for PCa. The overexpression of TUG1 promotes the proliferative and migratory capacities of PCa cells. Furthermore, TUG1 promotes the development of PCa by regulating RLIM through the TGF-β1/Smad pathway.

To analyze long non-coding RNAs taurine up-regulated gene 1 expression in middle ear cholesteatoma and its correlation with the degree of ossicle destruction. Sixty four patients with middle ear cholesteatoma admitted to our hospital from June 2019 to December 2020 were selected as the research participants for retrospective analysis. Middle ear cholesteatoma tissue and normal skin of the external auditory canal were obtained to determine taurine up-regulated gene 1 expression. Correlations of taurine up-regulated gene 1 with clinicopathological features and ossicle destruction as well as clinical efficacy were discussed. Moreover, patients were followed up for 1 y to observe taurine up-regulated gene 1’s impacts on disease recurrence. Taurine up-regulated gene 1 expression level increased in middle ear cholesteatoma tissue (p<0.001), was strongly linked to the course of disease, history of ear canal diseases and pathological staging (p<0.001). Taurine up-regulated gene 1 increased obviously in patients with complete ossicle destruction and decreased in patients with intact ossicles (p<0.001). Pearson correlation coefficient revealed a positive connection between taurine up-regulated gene 1 and the ossicle destruction score (r=0.791, p<0.001). Taurine up-regulated gene 1 was the lowest in the cured patients and was higher in ineffective patients than in improved patients (p<0.05). Spearman correlation coefficient identified an inverse connection between taurine up-regulated gene 1 and therapeutic efficacy. Patients were given with amoxicillin clavulanate potassium and prednisone after surgery and taurine up-regulated gene 1expression was significantly decreased by these anti-infection drugs. Taurine up-regulated gene 1 also increased in patients with recurrence during prognostic follow-up, with a sensitivity of 81.82 % and specificity of 86.00 % for predicting the 1 y recurrence in patients (p<0.001). Taurine up-regulated gene 1 is elevated in middle ear cholesteatoma and is closely linked to ossicle destruction in patients, which may be a breakthrough in diagnosing and treating middle ear cholesteatoma in the future.

Long non-coding RNAs (lncRNAs) are transcripts longer than 200 nucleotides that are not translated into proteins. lncRNA TUG1 (taurine upregulated gene 1) is highly expressed in various cancers, including glioblastoma. Previously we found that TUG1 is an essential molecule for cancer cells to cope with excessive replication stress in the S phase. Albeit its importance to cell cycle-related function, how it is dynamically regulated during the cell cycle is entirely unknown. Here, we established a system visualizing endogenous TUG1 molecules in live cells. TUG1 was tagged with stem-loop motifs recognized by a specific binding protein fused with GFP. We tracked TUG1 RNA by the GFP signal for 22 hours in T98G glioblastoma cells and found that the expression started from the later G1 phase. When cells were treated with Hydroxy Urea, a chemical that interferes with replication and increases replication stress, the expression of TUG1 was further upregulated in the S phase within 20 mins. We also observed some TUG1 molecules accumulated in several nuclear locations. It may indicate that TUG1 assembles to protect damaged DNA loci efficiently. Our results suggest that the expression of TUG1 is regulated in a cell cycle-dependent manner and is strongly connected with its function of TUG1. The current live-cell imaging system could help further discover the critical roles of TUG1 in cancer cells. Citation Format: Ayaka Minematsu. Visualizing dynamics of long non-coding RNA TUG1 in live glioblastoma cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6205.

The research aimed to explore the biological role of p53 protein and long non-coding RNA (lncRNA) taurine upregulated gene 1 (TUG1) in bupivacaine (bup)-induced neurotoxicity. Our work treated dorsal root ganglion (DRG) cells with bup, detected cell viability through CCK-8, apoptosis through TUNEL assays, DeoxyriboNucleic Acid (DNA) damage through γ-H2AX protein and comet assay, including p53 mRNA, protein and TUG1 expression through q-PCR and western blot, furthermore, cell viability and DNA damage were determined after the silencing of p53 and TUG1, biological information and TUG1 FISH combined with p53 protein immunofluorescence (IF) was performed to determine the cellular localization of these molecule. In vivo experiments, we explored the impact of intrathecal injection of bup on p53 mRNA and protein, TUG1, γ-H2AX protein expression. The results showed that bup was available to signally decreased cell viability, promoted apoptosis rate and DNA damage, additionally, bup increased p53 mRNA and protein and TUG1 expression. P53 siRNA and TUG1 siRNA significantly increased DNA damage. Furthermore, bioinformatics analysis and colocalization experiments revealed that the p53 protein is a transcription factor of TUG1, in vivo experiment, intrathecal injection of bup increased the p53 mRNA, p53 protein, TUG1 and γ-H2AX protein in the murine DRG. In this study, it was found p53 and TUG1 promote the repair of the DNA damage induced by bup in murine dorsal root ganglion cells, suggesting a new strategy for the amelioration of bup-induced neurotoxicity.

Long non-coding RNAs (lncRNAs) have been illustrated to contribute to the development of gestational diabetes mellitus (GDM). In the present study, we aimed to elucidate how lncRNA taurine upregulated gene 1 (TUG1) influences insulin resistance (IR) in a high-fat diet (HFD)-induced mouse model of GDM. We initially developed a mouse model of HFD-induced GDM, from which islet tissues were collected for RNA and protein extraction. Interactions among lncRNA TUG1/microRNA (miR)-328-3p/sterol regulatory element binding protein 2 (SREBP-2) were assessed by dual-luciferase reporter assay. Fasting blood glucose (FBG), fasting insulin (FINS), homeostasis model assessment of insulin resistance (HOMA-IR), HOMA pancreatic β-cell function (HOMA-β), insulin sensitivity index for oral glucose tolerance tests (ISOGTT) and insulinogenic index (IGI) levels in mouse serum were measured through conducting gain- and loss-of-function experiments. Abundant expression of miR-328 and deficient expression of lncRNA TUG1 and SREBP-2 were characterized in the islet tissues of mice with HFD-induced GDM. LncRNA TUG1 competitively bound to miR-328-3p, which specifically targeted SREBP-2. Either depletion of miR-328-3p or restoration of lncRNA TUG1 and SREBP-2 reduced the FBG, FINS, HOMA-β, and HOMA-IR levels while increasing ISOGTT and IGI levels, promoting the expression of the extracellular signal-regulated kinase (ERK) signaling pathway-related genes, and inhibiting apoptosis of islet cells in GDM mice. Upregulation miR-328-3p reversed the alleviative effects of SREBP-2 and lncRNA TUG1 on IR. Our study provides evidence that the lncRNA TUG1 may prevent IR following GDM through competitively binding to miR-328-3p and promoting the SREBP-2-mediated ERK signaling pathway inactivation.

BackgroundAccumulating evidence indicates that the long noncoding RNA taurine upregulated gene 1(TUG1) plays a critical role in cancer progression and metastasis. However, the overall biological role and clinical significance of TUG1 in hepatocellular carcinoma (HCC) remain largely unknown.MethodsThe expressions of TUG1, microRNA-216b-5p and distal-less homeobox 2 (DLX2) were detected by Quantitative real-time polymerase chain reaction (qRT-PCR). The target relationships were predicted by StarBase v.2.0 or TargetScan and confirmed by dual-luciferase reporter assay. The cell growth, apoptosis, migration and invasion were detected by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), Flow cytometry and Transwell assays, respectively. All protein expression levels were detected by western blot. Tumor xenografts were implemented to explore the role of TUG1 in vivo.ResultsWe found that there was a marked rise in TUG1 expression in HCC tissues and cells, and knockdown of TUG1 repressed the growth and metastasis and promoted apoptosis of HCC cells. In particular, TUG1 could act as a ceRNA, effectively becoming a sink for miR-216b-5p to fortify the expression of DLX2. Additionally, repression of TUG1 impared the progression of HCC cells by inhibiting DLX2 expression via sponging miR-216b-5p in vitro. More importantly, TUG1 knockdown inhibited HCC tumor growth in vivo through upregulating miR-216b-5p via inactivation of the DLX2.ConclusionTUG1 interacting with miR-216b-5p contributed to proliferation, metastasis, tumorigenesis and retarded apoptosis by activation of DLX2 in HCC.

RETRACTED: Long non-coding RNA TUG1 sponges microRNA-381-3p to facilitate cell viability and attenuate apoptosis in cervical cancer by elevating MDM2 expression

The aim of this study was to investigate the roles and potential mechanisms of long non-coding RNA (lncRNA) taurine upregulated gene 1 (TUG1) in the proliferation, migration, and invasion of Ewing's sarcoma cells. RT-qPCR was used to detect the expression of TUG1, microRNA-199a-3p (miR-199a-3p), and musashi2 (MSI2) in Ewing's sarcoma tissues and cell lines. Kaplan-Meier overall survival curves showed the survival rates of Ewing's sarcoma patients with high and low expression of TUG1. The association between the expressions of TUG1/MSI2 and miR-199a-3p in Ewing's sarcoma tissues was assessed by Pearson's correlation analysis. Cell proliferation, migration, and invasion were detected by CCK-8 assay and Transwell assay, respectively. The protein level of MSI2 was determined using western blotting. The interaction between TUG1/MSI2 and miR-199a-3p was validated by the dual-luciferase reporter assay. The levels of TUG1 and MSI2 were increased, while the level of miR-199a-3p was decreased in Ewing's sarcoma tissues and cells. High expression of TUG1 or MSI2 indicated a decreased overall survival rate of Ewing's sarcoma patients. TUG1/MSI2 level was negatively correlated with miR-199a-3p level. While TUG1 level was positively correlated with MSI2 level. In Ewing's sarcoma cells, knockdown of TUG1/MSI2 or overexpression of miR-199a-3p inhibited cell proliferation, migration, and invasion, whereas the overexpression of TUG1/MSI2 presented the opposite results. TUG1 functioned as a competing endogenous RNA to regulate MSI2 expression by sponging miR-199a-3p. Finally, miR-199a-3p inhibitor or MSI2 overexpression counteracted the TUG1 knockdown-mediated inhibitory effect on Ewing's sarcoma cell proliferation, migration, and invasion. TUG1 promotes proliferation, migration, and invasion of Ewing's sarcoma cells via sequestering miR-199a-3p to enhance the MSI2 expression, suggesting that TUG1 might be a potential target for treating Ewing's sarcoma.

The lncRNA taurine-upregulated gene 1 (TUG1) is known to serve a role as an oncogene in the development of a number of human malignancies. However, the functionality of TUG1 in osteosarcoma remains poorly characterized. Therefore, the aim of the present study was to explore the role of TUG1 in osteosarcoma. TUG1 expression in tumor tissues, adjacent healthy tissues and plasma from 40 osteosarcoma patients and 40 healthy controls was detected using reverse transcription-quantitative PCR. Receiver operating characteristic curves were used to analyze the diagnostic value of TUG1 for osteosarcoma while the prognostic value of TUG1 for osteosarcoma was analyzed using the Kaplan-Meier method. TUG1 expression vectors and siRNAs were transfected into MG-63 and U2OS osteosarcoma cell lines, and the effects on osteosarcoma cell viability, migration and invasion were tested using Cell Counting kit-8 and Transwell assays. The effects of TUG1 overexpression on runt-related transcription factor 2 (RUNX2) expression were also detected using western blotting. TUG1 expression was found to be significantly higher in osteosarcoma tissues compared with adjacent healthy tissues, and in the plasma of osteosarcoma patients compared with healthy controls. TUG1 expression also exhibited significant diagnostic and prognostic value for osteosarcoma. TUG1 overexpression and knockdown respectively increased and reducedosteosarcoma cell viability, migration and invasion. In addition, TUG1 overexpression upregulated RUNX2 expression. These results suggest that lncRNA TUG1 may promote the development of osteosarcoma by modulating RUNX2 and TUG1 expression, which can serve as prognostic and diagnostic markers for this malignancy.

Purpose Colorectal cancer (CRC) is one of the most fatal tumors worldwide. In Egypt, most CRC cases occur in individuals &gt; 40 years old. TUG1 has been proved to be disrupted in different malignancies and may have a critical role in tumor progression, invasion, and metastasis. However, its role in CRC has not been adequately studied. Materials / Methods Quantitative real-time polymerase chain reaction (PCR) was used to evaluate the expression levels of long non-coding RNA (LncRNA) taurine upregulated gene 1 (TUG1), in nonmetastatic and metastatic CRC tissues and adjacent noncancerous tissues as control. Results LncRNA TUG1 expression was significantly upregulated in both nonmetastatic and metastatic CRC tissues, in comparison with the adjacent noncancerous tissue. It was found that TUG1 could have a possible prognostic role in CRC, by comparing the sensitivity and specificity of TUG1 with those of CEA and CA19–9. Conclusion The results of the current study suggest that the LncRNA TUG1 participates in the malignant behaviors of CRC cells.

Serum expression and diagnostic potential of long non-coding RNAs NEAT1 and TUG1 in viral hepatitis C and viral hepatitis C-associated hepatocellular carcinoma

BackgroundColorectal cancer (CRC) is one of the third normal malignancy worldwide. Taurine-upregulated gene 1 (TUG1), a member of long noncoding RNAs (lncRNAs), has been reported to be involved in various cancers. However, the mechanism underlying TUG1 in the progression of CRC remains unclear.MethodsThe expression of TUG1, microRNA-542-3p (miR-542-3p), and tribbles homolog 2 (TRIB2) in CRC tissues and cells (LoVo and HCT116) were detected by quantitative real-time PCR (qRT-PCR). Methyl thiazolyl tetrazolium (MTT), transwell and flow cytometry assays were employed to evaluate the effects of TUG1 in CRC cells. The interaction between miR-542-3p and TUG1 or TRIB2 were verified by dual-luciferase reporter assay. A xenograft tumor model in nude mice was established to investigate the biological role of TUG1 in CRC in vivo.ResultsTUG1 was increased in CRC tissues and cells (LoVo and HCT116) in contrast with adjacent normal tissues and normal intestinal mucous cells (CCC-HIE-2). Downregulation of TUG1 or TRIB2 suppressed the proliferation, migration, invasion, and induced apoptosis in CRC cells. And knockdown of TUG1 repressed tumor growth in vivo. Besides, overexpression of TRIB2 reversed the effects of TUG1 depletion on the progression of CRC. Meanwhile, TUG1 interacted with miR-542-3p and TRIB2 was a target of miR-542-3p. Furthermore, miR-542-3p knockdown or TRIB2 overexpression partly reversed the suppression effect of TUG1 depletion on the Wnt/β-catenin pathway.ConclusionsTUG1 served as a tumor promoter, impeded the progression of CRC by miR-542-3p/TRIB2 axis to inactivate of Wnt/β-catenin pathway, which providing a novel target for CRC treatment.

The maxillofacial region in the human body is susceptible to fracture and corresponding soft tissue injury. In the current study, the effect of long non-coding RNA (lncRNA) taurine upregulated gene 1 (TUG1) on maxillofacial fracture development was investigated. In total, 50 patients diagnosed with maxillary fracture and 50 healthy volunteers were enrolled in this study. Participants' TUG1 expression level in serum was measured using reverse transcription-quantitative (RT-q)PCR. After transfection with small interfering (si)-TUG1, microRNA (miR)-214 mimic, miR-214 inhibitor, bone morphogenetic protein 2 (BMP2) mimic or a combination, the biological behavior of osteoblasts was evaluated using MTT, Transwell assays, RT-qPCR, flow cytometry and western blot analysis. Recovery experiments were used to explore the potential mechanism. Results demonstrated that TUG1 expression was decreased in the serum of patients with maxillary fractures. Knockdown of TUG1 repressed viability, migration and differentiation and induced apoptosis of osteoblasts. StarBase v2.0 revealed that TUG1 served as a sponge for miR-214 and BMP2 is a direct target of miR-214. Altogether, it was revealed that TUG1 expression was decreased in patients with maxillary fractures and TUG1 knockdown repressed the biological process of osteoblasts by sponging miR-214.

BackgroundLong noncoding RNAs (lncRNAs) play crucial roles in tumorigenesis, and lncRNA taurine-upregulated gene 1 (TUG1) has been proven to be associated with several human cancers. However, the mechanisms of TUG1-involved regulation remain largely unknown.MethodsWe examined the expressions of TUG1 in a cohort of 89 patients with non-small cell lung cancer (NSCLC) to determine the association between TUG1 expression and clinical parameters. We used circular chromosome conformation capture (4C) coupled with next-generation sequencing to explore the genome regions that interact with TUG1 and the TUG1-mediated regulation.ResultsTUG1 was significantly downregulated, and the TUG1 downregulation correlated with sex (p = 0.006), smoking status (p = 0.016), and tumor differentiation grade (p = 0.001). Knockdown of TUG1 significantly promoted the proliferation of NSCLC cells. According to the bioinformatic analysis result of TUG1 4C sequencing data, 83 candidate genes and their interaction regions were identified. Among these candidate genes, CUGBP and Elav-like family member 1 (CELF1) are potential targets of TUG1 in-trans regulation. To confirm the interaction between TUG1 and CELF1, relative expressions of CELF1 were examined in TUG1 knockdown H520 cells; results showed that CELF1 was significantly upregulated in TUG1 knockdown H520 cells. RNA immunoprecipitation was then performed to examine whether TUG1 RNA was bound to PRC2, a TUG1-involved regulation mechanism reported in previous studies. The results demonstrated that TUG1 RNA was bound to enhancer of zeste protein 2/embryonic ectoderm development (EZH2/EED), which is essential for PRC2. Finally, our designed ChIP assay revealed that the EZH2/EED was bound to the promotor region of CELF1 within 992 bp upstream of the transcript start site.ConclusionTUG1 is downregulated in NSCLC. Using TUG1 4C sequencing and bioinformatic analysis, we found CELF1 to be a potential target of TUG1 RNA in in-trans regulation. Moreover, subsequent experiments showed that TUG1 RNA could bind to PRC2 in the promotor region of CELF1 and negatively regulate CELF1 expressions in H520 cells. Our results may facilitate developing new treatment modalities targeting TUG1/PRC2/CELF1 interactions in patients with NSCLC.Electronic supplementary materialThe online version of this article (doi:10.1186/s12885-016-2569-6) contains supplementary material, which is available to authorized users.

Background/Aims: Pancreatic carcinoma (PC) is the one of the most common and malignant cancers worldwide. LncRNA taurine upregulated gene 1 (TUG1) was initially identified as a transcript upregulated by taurine, and the abnormal expression of TUG1 has been reported in many cancers. However, the biological role and molecular mechanism of TUG1 in PC still needs further investigation. Methods: Quantitative real-time PCR (qRT-PCR) was performed to measure the expression of TUG1 in PC cell lines and tissues. MTT and colony formation assays were used to measure the effect of TUG1 on cell proliferation. A wound healing assay, transwell assay and western blot assay were employed to determine the effect of TUG1 on cell migration and the epithelial mesenchymal transition (EMT) phenotype. RNA-binding protein immunoprecipitation (RIP) and a biotin-avidin pulldown system were performed to confirm the interaction between miR-328 and TUG1. A gene expression array analysis using clinical samples and RT-qPCR suggested that enhancer of zeste homolog 2 (EZH2) was a target of miR-382 in PC. Results: In this study, we reported that TUG1 was overexpressed in PC tissues and cell lines, and high expression of TUG1 predicted poor prognosis. Further experiments revealed that overexpressed TUG1 promoted cell proliferation, migration and contributed to EMT formation, whereas silenced TUG1 led to opposing results. Additionally, luciferase reporter assays, an RIP assay and an RNA-pulldown assay demonstrated that TUG1 could competitively sponge miR-382 and thereby regulate EZH2. Conclusion: Collectively, these findings revealed that TUG1 functions as an oncogenic lncRNA that promotes tumor progression, at least partially, by functioning as an endogenous ‘sponge’ and competing for miR-382 binding to the miRNA target EZH2.