LncRNA Nuclear Enriched Abundant Transcript 1 Research Articles

LncRNA NEAT1 promotes autophagy via regulating miR-204/ATG3 and enhanced cell resistance to sorafenib in hepatocellular carcinoma.

Long noncoding RNAs (lncRNAs) has been acknowledged in tumorigenesis gradually because of the great importance in different cancers. LncRNA nuclear enriched abundant transcript 1 (NEAT1) is a novel lncRNA and has been reported to promote multiple cancer progression. However, the biological roles of NEAT1 in hepatocellular carcinoma (HCC) is not cleared nowadays. In the present research, the level of NEAT1 was found to be upregulated in HCC by The Cancer Genome Atlas. In addition, NEAT1 expression is negatively correlated with the survival rate in HCC. Further investigation revealed that NEAT1 upregulation inhibited sorafenib efficacy and promoted autophagy. We found that NEAT1 could be a sponge for microRNA-204 (miR-204) and inhibits its level to upregulate ATG3 expression. In addition to the above, we demonstrated that miR-204 mimics also attenuated tumor autophagy. And rescue assays demonstrated that NEAT1 promotes HCC autophagy through modulating miR-204/ATG3 pathway. Collectively, this study first demonstrated that a novel NEAT1/miR-204/ATG3 signaling regulates HCC progression.

LncRNA NEAT1 promotes hepatic lipid accumulation via regulating miR-146a-5p/ROCK1 in nonalcoholic fatty liver disease

BackgroundNonalcoholic fatty liver disease (NAFLD) is a severe liver disease, which influences the health of people worldwide. However, the specific mechanism of the disease remains unknown, and effective treatments are still lacking. It was reported that Nuclear enriched abundant transcript 1 (NEAT1) obviously was up-regulated in NAFLD model. But the role and underlying mechanism of NEAT1 in NAFLD is unclear. MethodsHepG2 cells were treated by free fatty acids (FFA) and C57BL/6J mice were treated by high-fat diet to establish NAFLD in vitro and in vivo models, respectively. Cell transfection was applied to regulate the expression of NEAT1, ROCK1, and miR-146a-5p. Western blotting and qRT-PCR were used for measuring expression of protein and mRNA level, respectively. Dual luciferase assay was used to detect the target relationship. Oil Red O staining was used to measure the lipid accumulation. HE staining was used for observing pathological feature of liver tissues. ResultsHigh levels of NEAT1 and ROCK1, and low level of miR-146a-5p were identified in NAFLD models. NEAT1 could target miR-146a-5p to promote ROCK1 expression. Knockdown of NEAT1, overexpression of miR-146a-5p and knockdown of ROCK1 inhibited lipid accumulation through activating AMPK pathway. ConclusionNEAT1 may regulate NAFLD through miR-146a-5p targeting ROCK1, and further affect AMPK/SREBP pathway. This study may provide a new thought for the treatment of NAFLD.

YY1-induced upregulation of lncRNA NEAT1 contributes to OGD/R injury-induced inflammatory response in cerebral microglial cells via Wnt/β-catenin signaling pathway.

Stroke can lead to the serious long-term neurological disability. The dysregulation of long non-coding RNAs (lncRNAs) has been proven to be a pivotal factor for the progression of ischemic stroke. However, it is largely unknown whether lncRNAs regulated the OGD/R injury of cerebral microglial cells. In this study, we designed experiments to reveal the role of lncRNA Nuclear Enriched Abundant Transcript 1 (NEAT1) in the OGD/R injury of microglial cells. We found that NEAT1 contributed to the OGD/R injury and neuroinflammation damage in microglial cells. Moreover, the molecular mechanism involved in the NEAT1-mediated OGD/R injury. Mechanism investigation revealed that NEAT1 was upregulated by the transcription factor YY1. Moreover, Western blot analysis suggested that NEAT1 enhance the protein levels of core factors of Wnt/β-catenin signaling pathway, indicating that NEAT1 contributed to the activation of Wnt/β-catenin signaling pathway. Rescue assays were carried out in the microglial cells treated with OGD/R. The results showed that NEAT1 regulated the OGD/R injury and neuroinflammation damage via Wnt/β-catenin signaling pathway. In conclusion, our findings suggested that YY1-induced upregulation of NEAT1 contributed to the OGD/R injury and neuroinflammation damage of microglial cells via Wnt/β-catenin signaling pathway.

Long noncoding RNA NEAT1 functions as an oncogene in human laryngocarcinoma by targeting miR-29a-3p.

Long noncoding RNAs (lncRNAs) have been reported to participate in the progression and development of many human diseases. In this study, we are committed to uncover the potential function of lncRNA Nuclear Enriched Abundant Transcript 1 (NEAT1) in the development of laryngocarcinoma. LncRNA NEAT1 expression in laryngocarcinoma cells and 54 paired laryngocarcinoma samples was detected by Real-time quantitative polymerase chain reaction (RT-qPCR). Furthermore, the regulatory effects of NEAT1 on the proliferation and metastasis of laryngocarcinoma cells were evaluated. Biological role of NEAT1/miR-29a-3p axis was finally explored in regulating the progression of laryngocarcinoma. NEAT1 was upregulated in laryngocarcinoma tissues and cell lines. NEAT1 knockdown suppressed growth and invasive abilities in laryngocarcinoma cells, while overexpression of NEAT1 enhanced such abilities. Further experiments showed that miR-29a-3p was directly targeted by NEAT1, and participated in NEAT-mediated progression of laryngocarcinoma. NEAT1 is a novel oncogene in laryngocarcinoma and could enhance growth and invasion of laryngocarcinoma cells by targeting miR-29a-3p.

LncRNA NEAT1 promotes hypoxia-induced renal tubular epithelial apoptosis through downregulating miR-27a-3p.

Acute kidney injury (AKI) is a common kidney disorder that affects public health and the incidence of AKI. Sepsis, acute ischemia or hypoxia is the main reason for the occurrence of AKI. Recently, noncoding RNA that include microRNA and long noncoding RNA (lncRNAs) were reported to play important roles in AKI as well as have the potential to serve as a biomarker or therapeutic target for the development of the diagnostic and prognostic strategies of AKI. In the current study, we aimed to investigate the expression and biological function of lncRNA nuclear enriched abundant transcript 1 (NEAT1) in ischemia-induced AKI in patients' sample and in vitro. The expressions of NEAT1 and miR-27a-3p in ischemia/reperfusion-induced AKI patients were examined by quantitative reverse transcription polymerase chain reaction. Cell injury was induced by treatment of human kidney tubular cells (HK-2) with CoCl2 . After treatment, the influences of NEAT1 and miR-27a-3p on the cell apoptosis in the CoCl2 -stimulated HK-2 were tested by flow cytometry. The flow analysis results showed that the expression of NEAT1 was markedly higher in the ischemia-induced AKI patients compared with normal control. Moreover, repression the expression of NEAT1 decreased CoCl2 -induced injury in HK-2. The expression of miR-27a-3p was negatively regulated by NEAT1. Inhibition the expression of NEAT1 attenuated overexpression of miR-27a-3p enhanced CoCl2 -induced injury. In summary, an ischemia-induced injury may be enhanced by a high level of NEAT1 through targeting miR-27a-3p. Thus, NEAT1 has the potential to be explored as a biomarker for diagnosis and target for therapeutic strategies in ischemia-induced AKI.

Silence of long noncoding RNA NEAT1 exerts suppressive effects on immunity during sepsis by promoting microRNA-125-dependent MCEMP1 downregulation.

Accumulating studies have recognized microRNAs (miRs) and long noncoding RNAs (lncRNAs) as important molecules involved in the mediation of various biological processes, including innate immunity. In this study, we investigated a novel noncoding RNA regulatory circuitry in the immunity during sepsis. A cecal ligation and puncture-induced sepsis mouse model was established to determine the expression of mast cell expression membrane protein 1 (MCEMP1). The RNA crosstalk among lncRNA nuclear enriched abundant transcript 1 (NEAT1), miR-125, and MCEMP1 was validated. Subsequently, the levels of lncRNA NEAT1, miR-125, and MCEMP1 in T lymphocytes isolated from sepsis mice were up- or downregulated by exogenous transfection in an attempt to investigate their effects on the release of inflammatory factors, the expression of immunoglobulins, the activity of T cell subsets and natural killer (NK) cells, as well as T lymphocyte apoptosis. In sepsis mice, MCEMP1 was highly expressed and verified to be a target gene of miR-125. RNA crosstalk experiment revealed that lncRNA NEAT1 directly inhibited miR-125 to upregulate MCEMP1. We also observed that elevation of miR-125, depletion of MCEMP1, or downregulation of lncRNA NEAT1 resulted in promoted T lymphocyte activity, immunoglobulin expression, and NK cell activity, and inhibited release of inflammatory factors and T lymphocyte apoptosis. Taken together, these findings provided evidence that the downregulation of lncRNA NEAT1 could promote miR-125 to exert an inhibitory effect on the immunity in septic mice by suppressing MCEMP1, highlighting a potential target for the treatment of sepsis. © 2019 IUBMB Life, 2019.

Long noncoding RNA nuclear enriched abundant transcript 1 impacts cell proliferation, invasion, and migration of glioma through regulating miR-139-5p/ CDK6.

We aimed to explore the impact of long noncoding RNA (lncRNA) nuclear enriched abundant transcript 1 (NEAT1) on cell proliferation, invasion, and migration of glioma. Differentially expressed genes were screened out from Gene Expression Omnibus data set based on the microarray analysis. The expression levels of lncRNA NEAT1, miR-139-5p, and CDK6 in glioma cells and tissues were examined by quantitative reverse transcription polymerase chain reaction, and the protein level of CDK6 in glioma cells was determined by western blot and immunohistochemistry. Glioma cell viability, cell cycle, and apoptosis were detected by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT) and flow cytometry, respectively, whereas cell invasion and migration were analyzed by transwell assay. The target relationships among NEAT1, miR-139-5p, and CDK6 were confirmed by dual-luciferase reporter gene assay. The effects of lncRNA NEAT1 on tumor growth were further testified through glioma xenografts in nude mice. LncRNA NEAT1 and CDK6 were highly expressed in glioma tissues and cells, whereas miR-139-5p was lowly expressed. There were target relationships and correlations on expressions between miR-139-5p and NEAT1/ CDK6. NEAT1 and CDK6 could promote cell proliferation and metastasis of glioma cells and impeded cell apoptosis, whereas miR-139-5p exerted suppressive effects on the biological functions of glioma cells. NEAT1 regulated CDK6 to affect glioma growth through sponging miR-139-5p. LncRNA NEAT1 promotes cell proliferation, invasion, and migration of glioma through regulating miR-139-5p/CDK6 pathway.

The long noncoding RNA NEAT1 and nuclear paraspeckles are up-regulated by the transcription factor HSF1 in the heat shock response

The long noncoding RNA (lncRNA) NEAT1 (nuclear enriched abundant transcript 1) is the architectural component of nuclear paraspeckles, and it has recently gained considerable attention as it is abnormally expressed in pathological conditions such as cancer and neurodegenerative diseases. NEAT1 and paraspeckle formation are increased in cells upon exposure to a variety of environmental stressors and believed to play an important role in cell survival. The present study was undertaken to further investigate the role of NEAT1 in cellular stress response pathways. We show that NEAT1 is a novel target gene of heat shock transcription factor 1 (HSF1) and is up-regulated when the heat shock response pathway is activated by sulforaphane (SFN) or elevated temperature. HSF1 binds specifically to a newly identified conserved heat shock element in the NEAT1 promoter. In line with this, SFN induced the formation of NEAT1-containing paraspeckles via an HSF1-dependent mechanism. HSF1 plays a key role in the cellular response to proteotoxic stress by promoting the expression of a series of genes, including those encoding molecular chaperones. We have found that the expression of HSP70, HSP90, and HSP27 is amplified and sustained during heat shock in NEAT1-depleted cells compared with control cells, indicating that NEAT1 feeds back via an unknown mechanism to regulate HSF1 activity. This interrelationship is potentially significant in human diseases such as cancer and neurodegenerative disorders.

The Expression of lncRNA NEAT1 in Human Tuberculosis and Its Antituberculosis Effect.

Increasing evidence suggests that lncRNA is important in innate immune responses. Recent study has demonstrated that lncRNA NEAT1 (which has two subtypes: NEAT1_1 and NEAT1_2) nuclear-enriched abundant transcript 1 (NEAT1) is essential in immune regulation, but the expression and clinical significance in tuberculosis are still unclear. In this work, we aimed to discuss the expression and clinical significance of NEAT1 in tuberculosis patients. Quantitative real-time polymerase chain reaction was performed to detect the expression of NEAT1 (both NEAT1_1 and NEAT1_2) in peripheral blood mononuclear cells (PBMCs) of patients with tuberculosis and healthy controls and analyze the association of NEAT1 with the development, progression, and outcome of tuberculosis. Then NEAT1 was silenced in THP-1 cells using siRNA. The expression of tumor necrosis factor- (TNF-) α and interleukin- (IL-) 6 was detected after Mycobacterium tuberculosis (Mtb) infection, and the change in bactericidal capacity against Mtb was assessed. We demonstrated that the relative expression of NEAT1 (both NEAT1_1 and NEAT1_2) in patients with tuberculosis was higher than that in the control. However, the expression of NEAT1 (both NEAT1_1 and NEAT1_2) in the new case and relapse groups had insignificant differences. The level of NEAT1 (both NEAT1_1 and NEAT1_2) in PBMCs declined gradually with treatment and was restored to the normal level. The expression of NEAT1 (both NEAT1_1 and NEAT1_2) in THP-1 cells increased markedly after Mtb infection. The levels of IL-6 but not TNF-α in Mtb-infected THP-1 cells declined after the NEAT1 (both NEAT1_1 and NEAT1_2) knockout. The survival of Mtb in NEAT1-knockout (both NEAT1_1 and NEAT1_2) THP-1 cells reached its peak 72 h after infection, taking 0 h after Mtb infection as the baseline data; the difference was statistically significant compared with the control. Thus, our results indicate that the expression of NEAT1 increased during Mtb infection, and it might be associated with the outcome of tuberculosis. The decreased expression of NEAT1 might weaken the clearance of intracellular Mtb by macrophages.

LncRNA NEAT1 promotes the tumorigenesis of colorectal cancer by sponging miR-193a-3p.

ObjectivesLncRNA nuclear‐enriched abundant transcript 1 (NEAT1) participates in the development and progression of multiple malignancies. However, the molecular mechanism by which NEAT1 contributes to colorectal cancer (CRC) remains unclear.MethodsThe association between lncRNA NEAT1 expression and clinicopathological characteristics and prognosis in patients with CRC was analysed by TCGA RNA‐sequencing data. MTT, colony formation, flow cytometry, transwell assays and a xenograft tumour model were used to assess the functions of NEAT1. Bioinformatics and spearman correlation analysis were used to identify the NEAT1‐specific binding with miRNAs, and luciferase gene report and RIP assays were performed to confirm the interaction between miR‐193a‐3p (miR‐193a) and NEAT1 in CRC cells.ResultsUpregulation of NEAT1 expression was significantly correlated with TNM stage, poor survival and tumour recurrence in patients with CRC, and acted as an independent prognostic factor for tumour recurrence. Knockdown of NEAT1 suppressed cell proliferation, colony formation abilities and invasive potential and induced cell apoptosis, but overexpression of NEAT1 reversed these effects. Furthermore, NEAT1 was confirmed to act as a sponge of miR‐193a, and knockdown of NEAT1 attenuated miR‐193a inhibitor‐induced tumour promoting effects and L17RD expression in CRC cells. miR‐193a harboured negative correlation with NEAT1 and IL17RD expression in CRC specimens. In vivo experiment further validated the inhibitory effects of NEAT1 knockdown on xenograft tumour growth.ConclusionOur findings demonstrate that lncRNA NEAT1 acts as an oncogenic role in CRC cells by sponging miR‐193a and may represent a potential marker for CRC patients.

LncRNA NEAT1 promotes inflammatory response and induces corneal neovascularization

Human corneal fibroblasts (HCFs) are implicated in corneal neovascularization (CRNV). The mechanisms underlying the inflammatory response in HCFs and the development of CRNV were explored in this study. Alkali burns were applied to the corneas of rats to establish a CRNV model. The expression of long noncoding RNA (lncRNA) nuclear enriched abundant transcript 1 (NEAT1) and mRNA and protein levels of nuclear factor kappa B (NF-κB)- activating protein (NKAP) were examined by quantitative real-time (qRT-PCR) and Western blot methods, respectively. Lipopolysaccharide (LPS) is used to stimulate HCFs for inflammatory response. The level of inflammation factors in HCF supernatant was detected using an enzyme-linked immunosorbent assay (ELISA). Binding and interactions between NEAT1 and miRNA 1246 (miR-1246) were determined by RNA immunoprecipitation (RIP) and RNA pull-down assays in HCFs. Compared with the control group (n = 6), NEAT1 was upregulated in the corneas of the CRNV rat model (n = 6). The expression of NEAT1 in HCFs was upregulated by LPS. Downregulation of NEAT1 suppressed the secretion of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). NEAT1 could bind and interact with miR-1246. LPS regulated the expression of NKAP and NF-κB signaling via the NEAT1/miR-1246 pathway. Downregulation of NEAT1 in vivo inhibited CRNV progression in the CRNV rat model. The lncRNA NEAT1 induced secretion of inflammatory factors, mediated by NF-κB, by targeting miR-1246, thereby promoting CRNV progression.

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.

NEAT1 induces osteosarcoma development by modulating the miR-339-5p/TGF-β1 pathway.

The long noncoding RNA (lncRNA) nuclear enriched abundant transcript 1 (NEAT1) has been recognized as a tumor oncogene involved in the development of multiple cancers. However, the function of NEAT1 and its molecular mechanism in osteosarcoma (OS) remain unclear. First, we detected the NEAT1 expression in OS cell lines by performing quantitative reverse-transcription polymerase chain reaction. Next, the effects of NEAT1 on OS cell growth, apoptosis, migration, and invasion were tested by lentivirus-mediated downregulation. We observed that inhibition of NEAT1 restrained OS cell progression greatly. Interestingly, in the last few years, increasing studies have shown that some lncRNAs can act as miRNA sponges and reduce the amount of the same. Here, we found that NEAT1 can modulate OS development via sponging miR-339-5p. MiR-339-5p was significantly decreased in OS cells, and its overexpression can remarkably repress the OS proliferation. These results indicated that NEAT1 could function as a tumor oncogene in OS by inhibiting miR-339-5p in vitro. Then, the following assays validated that transforming growth factor β1 (TGF-β1) can act as a functional target of miR-339-5p in OS cells. Finally, we indicated that NEAT1 could mediate TGF-β1 expression by competitively sponging miR-339-5p. NEAT1 induced OS cell proliferation and cell mobility by binding to miR-339-5p and increasing TGF-β1 in OS. It was demonstrated in our study that lncRNA NEAT1 could impede miR-339-5p expression to maintain the expression of TGF-β1, which led to the development of OS. Our findings implied that the novel identified NEAT1/miR-339-5p/TGF-β1 axis might be a new molecular pathway or therapeutic target for OS diagnosis and treatment.

Biological Function and Mechanism of Long Noncoding RNAs Nuclear-Enriched Abundant Transcript 1 in Development of Cervical Cancer.

Background:Accumulating documents have demonstrated that long noncoding RNAs (lncRNAs) play critical roles in tumorigenesis. As an lncRNA, nuclear-enriched abundant transcript 1 (NEAT1) has been identified to be involved in the progression of many types of cancers. However, the biological function of NEAT1 in cervical cancer is not fully investigated. The aim of this study was to disclose the specific biological function of lncRNA NEAT1 in cervical cancer progression.Methods:Quantitative real-time polymerase chain reaction (qRT-PCR) was utilized to identify the expression of lncRNA NEAT1 in the cervical cancer tissues and cell lines. All cervical cancer samples used in this study were collected from the Affiliated Suzhou Hospital of Nanjing Medical University between September 2012 and September 2017. The correlation between NEAT1 expression and the overall survival rate of cervical cancer patients was analyzed by Kaplan-Meier analysis. The effects of NEAT1 knockdown or overexpression on cell proliferation were tested by performing MTT assays and colony formation assays. Transwell assays were conducted to detect the migratory ability of cervical cancer cells, in which NEAT1 was silenced or overexpressed. Western blotting was utilized to validate whether NEAT1 promotes cervical cancer progression through activating PI3K-Akt signaling pathway.Results:High expression of NEAT1 predicted poor prognosis of cervical cancer patients (χ2 = 0.735, P = 0.005). Knockdown of NEAT1 decreased the number of colonies in CaSki cell from 136.667 ± 13.503 to 71.667 ± 7.506 (t = −18.76, P = 0.003) and decreased the number of colonies in HeLa cell from 128.667 ± 13.317 to 65.667 ± 7.024 (t = −5.54, P = 0.031). However, overexpression of NEAT1 increased the number of colonies in SiHa cell from 84.667 ± 12.014 to 150.667 ± 18.037 (t = 7.27, P = 0.018). Knockdown of NEAT1 decreased the migratory number of CaSki cell from 100.333 ± 9.866 to 58.333 ± 5.859 (t = −8.08, P = 0.015) and reduced the migratory number in HeLa cell from 123.667 ± 12.097 to 67.667 ± 7.095 (t = −6.03, P = 0.026). Overexpression of NEAT1 increased the migratory number of SiHa cell from 127.333 ± 16.042 to 231.333 ± 31.786 (t = 4.92, P = 0.039).Conclusion:NEAT1 may exert oncogenic function in cervical cancer and serve as a novel therapeutic target for cervical cancer.

The lncRNA NEAT1 activates Wnt/\u03b2-catenin signaling and promotes colorectal cancer progression via interacting with DDX5

BackgroundThe long noncoding RNA nuclear-enriched abundant transcript 1 (NEAT1) has been reported to be overexpressed in colorectal cancer (CRC). However, its underlying mechanisms in the progression of CRC have not been well studied.MethodsTo investigate the clinical significance of NEAT1, we analyzed its expression levels in a publicly available dataset and in 71 CRC samples from Fudan University Shanghai Cancer Center. Functional assays, including the CCK8, EdU, colony formation, wound healing, and Transwell assays, were used to determine the oncogenic role of NEAT1 in human CRC progression. Furthermore, RNA pull-down, mass spectrometry, RNA immunoprecipitation, and Dual-Luciferase Reporter Assays were used to determine the mechanism of NEAT1 in CRC progression. Animal experiments were used to determine the role of NEAT1 in CRC tumorigenicity and metastasis in vivo.ResultsNEAT1 expression was significantly upregulated in CRC tissues compared with its expression in normal tissues. Altered NEAT1 expression led to marked changes in proliferation, migration, and invasion of CRC cells both in vitro and in vivo. Mechanistically, we found that NEAT1 directly bound to the DDX5 protein, regulated its stability, and sequentially activated Wnt signaling. Our study showed that NEAT1 indirectly activated the Wnt/β-catenin signaling pathway via DDX5 and fulfilled its oncogenic functions in a DDX5-mediated manner. Clinically, concomitant NEAT1 and DDX5 protein levels negatively correlated with the overall survival and disease-free survival of CRC patients.ConclusionsOur findings indicated that NEAT1 activated Wnt signaling to promote colorectal cancer progression and metastasis. The NEAT1/DDX5/Wnt/β-catenin axis could be a potential therapeutic target of pharmacological strategies.

Resveratrol inhibits proliferation, migration and invasion of multiple myeloma cells via NEAT1-mediated Wnt/β-catenin signaling pathway

PurposeTo study the influence of resveratrol on proliferation, migration and invasion of multiple myeloma (MM) cells through the long noncoding RNA (lncRNA) NEAT1 (nuclear enriched abundant transcript 1)-modulated Wnt/β-catenin signaling pathway. MethodsMicroarray analysis was used to screen aberrantly expressed lncRNAs from MM cells and normal plasmocytes. The effects of NEAT1 overexpression/silencing or resveratrol treatment on MM cell (U266 and LP1) proliferation, migration and invasion were investigated using CCK-8 (Cell Counting Kit-8), wound healing and Transwell invasion assays. Expression of Wnt/β-catenin related proteins and unfolded protein response (UPR)-related proteins was detected by western blot. ResultslncRNA NEAT1 was highly expressed in MM cells, which could be significantly inhibited by resveratrol. NEAT1 overexpression induced proliferation, migration and invasion of MM cells, while resveratrol counteracted its effect. NEAT1 upregulated protein expression in the Wnt/β-catenin signaling pathway, while resveratrol reversed the negative effect of NEAT1 overexpression on MM cells through the Wnt/β-catenin signaling pathway, and hence suppressed MM cell reproduction, migration and invasion. Resveratrol could also restrain unfolded protein response in MM cells. ConclusionResveratrol downregulated the expression of lncRNA NEAT1 in MM cells and inhibited proliferation, migration and invasion of MM cells by suppressing the Wnt/β-catenin signaling pathway and unfolded protein response.

Long non-coding RNA NEAT1 promotes proliferation, migration and invasion of human osteosarcoma cells.

Aim: Long non-coding RNAs (LncRNAs) have been identified to play a crucial role in tumorigenesis and the progression of many types of tumors. However, the clinical significance and biological function of lncRNA nuclear-enriched abundant transcript 1(NEAT1) in human osteosarcoma remains unknown. Here, we investigated the role of NEAT1 in human osteosarcoma cell lines and clinical tumor samples.Methods: In this study, expression of NEAT1 was analyzed in 19 osteosarcoma tissues and paired adjacent non-tumor tissues by using quantitative real-time PCR. Additionally, knockdown of NEAT1 expression using Lentivirus-mediated siRNA was performed in order to explore the biological function of NEAT1 on osteosarcoma cell proliferation and metastasis through MTT, colony formation assay and transwell assay.Results: NEAT1 was over-expressed in osteosarcoma tissues compared with adjacent non-tumor tissues. In addition, knockdown of NEAT1 expression could suppress cell proliferation, migration and invasion in vitro.Conclusion: LncRNA NEAT1 was up-regulated in osteosarcoma tissue, promoting proliferation and metastasis of osteosarcoma cells. These findings indicate the role of this substance, as a growth regulator in osteosarcoma, and thus it may serve as a novel biomarker, and drug target for developing osteosarcoma therapies.

The LncRNA NEAT1 Accelerates Lung Adenocarcinoma Deterioration and Binds to Mir-193a-3p as a Competitive Endogenous RNA

Background/Aims: Long noncoding RNAs (lncRNAs) contribute to the development of multiple malignant tumors. Here, we focused on the biological function and underlying molecular mechanism of an lncRNA, nuclear-enriched abundant transcript 1 (NEAT1), in lung adenocarcinoma (LUAD). Methods: In vitro experiments were conducted to determine the biological effects of NEAT1 in LUAD cells. A luciferase activity reporter assay was performed to corroborate the interaction between NEAT1 and miR-193a-3p. Data from Gene Expression Omnibus (GEO), Oncomine, The Cancer Genome Atlas (TCGA), and our in-house reverse transcription quantitative PCR (RT-qPCR) were combined to examine the expression of NEAT1 and miR-193a-3p in LUAD. To further explore the regulatory mechanism of NEAT1, we searched for putative target genes of miR-193a-3p from 12 online prediction databases and determined genes positively correlated with NEAT1 as candidate targets. Furthermore, we analyzed the expression of these selected genes using data from TCGA. Results: In vitro experiments showed that knockdown of NEAT1 in LUAD cells markedly restrained cell proliferation, invasion, and migration and stimulated cell apoptosis. The dual-luciferase reporter assay demonstrated that miR-193a-3p directly targeted NEAT1 at its 3’-UTR. We then detected NEAT1 and miR-193a-3p in LUAD cells and normal lung epithelial cells and discovered high expression of NEAT1 and low expression of miR-193a-3p in LUAD cell lines. Simultaneously, the pooled results from the GEO, Oncomine, TCGA, and in-house RT-qPCR showed that the NEAT1 expression increased while the miR-193a-3p expression decreased in LUAD tissues versus normal lung tissues. Furthermore, the USF1 gene was not only upregulated in LUAD, but also positively correlated with NEAT1, suggesting that NEAT1 may function as a ceRNA to sponge miR-193a-3p and abrogate the inhibitory effect of miR-193a-3p on USF1. Conclusions: Our findings indicate that NEAT1 plays important roles in the occurrence and progression of LUAD. It may exert its role by acting as a ceRNA to regulate miR-193a-3p.

C/EBPβ contributes to transcriptional activation of long non-coding RNA NEAT1 during APL cell differentiation

Emerging evidences have shown that long non-coding RNAs (lncRNAs) play critical roles in cancer development and cancer therapy. LncRNA Nuclear Enriched Abundant Transcript 1 (NEAT1) is indispensable during acute promyelocytic leukemia (APL) cell differentiation induced by all-trans retinoic acid (ATRA). However, the precise mechanism of NEAT1 upregulation has not been fully understood. In this study, we performed chromatin immunoprecipitation and luciferase reporter assays to demonstrate that C/EBP family transcription factor C/EBPβ bind to and transactivate the promoter of lncRNA NEAT1 through the C/EBPβ binding sites both around −54 bp and −1453 bp upstream of the transcription start site. Moreover, the expression of C/EBPβ was increased after ATRA treatment, and the binding of C/EBPβ in the NEAT1 promoter was also dramatically increased. Finally, knockdown of C/EBPβ significantly reduced the ATRA-induced upregulation of NEAT1. In conclusion, C/EBPβ directly activates the expression of NEAT1 through binding to the promoter of NEAT1. Knockdown of C/EBPβ impairs ATRA-induced transcriptional activation of NEAT1. Our data indicate that C/EBPβ contributes to ATRA-induced activation of NEAT1 during APL cell differentiation. Our results enrich our knowledge on the regulation of lncRNAs and the regulatory role of C/EBPβ in APL cell differentiation.

Silence of Long Noncoding RNA NEAT1 Inhibits Malignant Biological Behaviors and Chemotherapy Resistance in Gastric Cancer.

Gastric cancer (GC) is the most common solid tumor in digestive system. Nuclear-enriched abundant transcript 1 (NEAT1) gene is a lncRNA, and reveal potential oncogene role in several malignant tumors. The aim of this study is to investigate the expression and clinical significance of Nuclear Paraspeckle Assembly Transcript 1 (NEAT1) gene and its influence to malignant biologic behaviors and chemotherapy resistance to adriamycin in GC. This study found NEAT1 was up-regulated in GC tissues and cells, especially in in GC adriamycin-resistant cells. NEAT1 silence in SGC7901 cells could inhibit proliferation and invasion ability, and promote cell apoptosis significantly. NEAT1 silence in adriamycin-resistant SGC7901/ADR cells also depressed the half maximal inhibitory concentration (IC50) for adriamycin, chemotherapy resistance to adriamycin was inhibited significantly. NEAT1 knockdown promoted apoptosis in SGC7901/ADR cells induced by adriamycin. In summary, lncRNA NEAT1 is high-expressed in GC and functions as an oncogene to modulate apoptosis, invasion, proliferation and chemotherapy resistance of GC cells, which might be a novel potential therapeutic target for GC.