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Objective To investigate the effect of long non-coding RNA (IncRNA) nuclear-enriched abundant transcript 1 (NEATl) on hypoxia-reoxygenation (H/R) glial astrocyte injury, and to explore whether the mechanism was related to the regulation of micro RNA (miR)-761. Methods Rat cortical astrocytes were cultured to construct a H/R injury model. Astrocytes were divided into control group, model group, model+ small interfering RNA negative control (si-NC) group, model+ si-NEATl group, model+ miR-NC group, model + miR-761 group, model + si-NEATl + anti-miR-NC group, model+si-NEATl+anti-miR-761 group. Expression of NEATl and miR-761 were detected by Real-time PCR. The experiment was repeated 3 times. The content of malonaldefryde (MDA), and the activity of superoxide dismutase (SOD) and catalase (CAT) were detected by kits. Dual luciferase reporter experiment and Real-time PCR were used to analyze the targeting relationship between NEATl and miR-761. The experiment was repeated 3 times. Results Compared with the control group, the cell apoptosis rate and MDA content of the model group increased significantly, SOD and CAT activities decreased significantly, NEATl expression increased significantly, and miR-761 expression decreased significantly (P< 0. 05). Compared with the model+si-NC group, the apoptosis rate and MDA content of the model+si-NEATl group reduced significantly, and SOD and CAT activities increased significantly (P < 0 . 0 5) . Compared with the model + miR-NC group, the apoptosis rate and MDA content of the model + miR-761 group reduced significantly, and SOD and CAT activities increased significantly (P < 0 . 0 5) . MiR-761 was the target gene of N E A T l, and NEATl negatively regulated miR-761 expression. Compared with the model+si-NEATl+anti-miR-NC group, the apoptosis rate and MDA content of the model+siNEAT1+anti-miR-761 group increased significantly, and SOD and CAT activities decreased significantly (P < 0 . 0 5) . Conclusion Interference with NEATl expression can protect astrocytes from H / R injury by up-regulating miR-761.
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Objective:To investigate the correlations between expression of long noncoding RNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), nuclear-enriched abundant transcript 1 (NEAT1) and their functions on exosome secretion, proliferation and invasion in hepatocellular carcinoma (HCC).Methods:We used small interfering RNA of MALAT1 (si-MALAT1) to knockdown MALAT1 in HuH-7. At the meanwhile, cells which were transfected with si-NC were used as the negative control group. Expression of NEAT1, cell proliferation and invasion function were detected these two groups. HuH-7 cells were transfected with lentivirus NEAT1 over expressing vector (lv-NEAT1) or negative control (lv-control). Expression of exosomes secretion related genes were analyzed between lv-NEAT1 and lv-control groups. Cells of lv-NEAT1 were knockdown MALAT1 expression using si-MALAT1, which could be si-MALAT1+ lv-NEAT1 group. exosomes secretion was detected in si-NC, si-MALAT1 and si-MALAT1+ lv-NEAT1 group. We treated cells (si-MALAT1 group) with exosomes from cells with lv-NEAT1 or lv-control to divide cells as si-MALAT1+ exosomes of lv-NEAT1 cells and si-MALAT1+ exosomes of lv-control groups. Cell proliferation and invasion of cells were detected in two groups.Results:Low expression of NEAT1 were found in MALAT1 knockdown cells compared with si-NC group [(0.72±0.02) vs. (0.98±0.01), P<0.05]. Cells with MALAT1 knockdown shown diminished proliferation [(0.66±0.03) vs. (0.98±0.04), P<0.05)] and invasion [(88.33±7.26) vs. (147.70±13.62), P<0.05)]. Compared with si-NC group, CD9 and CD63 expression were decreased in exosomes of si-MALAT1 group. Compared with si-MALAT1 group, CD9 and CD63 expression was increased in exosomes of si-MALAT1+ lv-NEAT1 group. Compared with si-MALAT1+ exosomes of lv-control group, proliferation [(0.97±0.03) vs. (0.74±0.05), P<0.05)] and invasion [ (132.70±7.36) vs. (98.33±6.01), P<0.05) ] were increased in si-MALAT1+ exosomes of lv-NEAT1 group. Exosomes related genes expression including HSPA8 (5.53±0.31), SLC3A2 (0.32±0.07) and SLC7A5 (0.77±0.45) were changed in lv-NEAT1 group compared with lv-control group [(0.98±0.15), P<0.05]. Conclusion:MALAT1 induced exosomes secretion by NEAT1 and exosomes related genes regulation. This regulation might be related with increased proliferation and invasion function in HCC cells with MALAT1 and NEAT1 abnormal expression.
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Objective:To explore the impact of the expression of long noncoding RNA-nuclear-enriched abundant transcript 1 (NEAT1) on neurological function and neuronal apoptosis after traumatic brain injury (TBI) in mice and the possible mechanism.Methods:According to the random number table, 90 C57BL/6J mice were divided into sham group, blank control group, empty virus group 1, empty virus group 2, NEAT1 over-expression group and NEAT1 knockdown group, with 15 mice per group. The traumatic brain injury (TBI) was simulated by controlled cortical injury (CCI) model, and NEAT1 was regulated by intracerebroventricular injection with recombinant adenovirus. The neurological severity score (NSS) and Morris water maze test were used to evaluate the neurological function in blank control group, NEAT1 over-expression group and NEAT1 knockdown group within 1 week and 14-21 days after injury. The Western blot was used to observe the expressions of P53-induced protein with a death domain 1 (Pidd1), caspase-2, caspase-9 and caspase-3 in blank control group at 6 hour and 1, 3, 7 days after injury. The TUNEL method and immunofluorescence were used to observe the neurological apoptosis and expression of Pidd1 in blank control group, NEAT1 over-expression group and NEAT1 knockdown group at 3 days after injury. The Western blot analysis was used to detect protein expressions of Pidd1, caspase-2, cytochrome c (Cyt c) and caspase-3 in sham group, blank control group, empty virus groups, NEAT1 over-expression group and NEAT1 knockdown group at 3 days after injury.Results:The NSS was significantly reduced in NEAT1 over-expression group [(3.5±0.7)points], and was significantly increased in NEAT1 knockdown group [(5.0±1.5)points]at day 1 after injury, when compared with blank control group [(4.9±1.0)points]( P<0.01). The Morris water maze test showed that the time to find platform was decreased in NEAT1 over-expression group[(10.9±2.8)seconds], and was prolonged in NEAT1 knockdown group [(30.7±6.2)seconds] at day 19 after injury ( P<0.05 or 0.01), when compared with blank control group [(20.1±5.6)seconds]. The Western blot analysis showed that the expressions of Pidd1, caspase-2, caspase-9 and caspase-3 had significant increase at day 3 after injury ( P<0.01). The TUNEL test showed that the apoptosis rate of neurons was significantly decreased in NEAT1 over-expression group [(18.0±2.7)%], and the apoptosis rate was significantly increased in NEAT1 knockdown group [(63.0±8.6)%] at day 3 after injury ( P<0.01). Immunofluorescence showed that the expression of Pidd1 protein in cytoplasm of the neurons was decreased in NEAT1 over-expression group [(22.7±2.2)%]( P<0.01), and was increased in NEAT1 knockdown group [(72.7±7.0)%]( P<0.01) at day 3 after injury, when compared with blank control group. The Western blot analysis showed that the expressions of Pidd1, capsase-2, Cyt c and caspase-3 were significantly reduced in NEAT1 over-expression group (0.5±0.0, 0.3±0.0, 0.5±0.0, 0.4±0.0) at day 3 after injury, when compared with blank control group. However, the results were opposite in NEAT1 knockdown group. Conclusion:After TBI, the NEAT1 can reduce the activation of caspase-3 through the Pidd1-caspase-2-Cyt c pathway after TBI, regulate neuronal apoptosis, and ultimately play a protective role in neurological function.
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@# Objective: To investigate the effects of long non-coding RNA nuclear enriched abundant transcript 1 (lncRNA NEAT1) on the proliferation of lung adenocarcinoma PC-9 cells and to explore its mechanism. Methods: qPCR was used to detect the expression level of lncRNA NEAT1 in human lung adenocarcinoma PC-9 cells and human embryonic lung diploid 2BS cells. The sequence of small interfering RNA(siRNA) targeting lncRNANEAT1 gene was designed and synthesized, and then transfected into PC-9 cells by liposome method. The expression level of NEAT1 in PC-9 cells before and after transfection was detected by qPCR. MTT and flow cytometry were used to detect the effect of lncRNANEAT1 knockdown on proliferation and cell cycle distribution of PC-9 cells, respectively. WB assay was used to detect the expressions of DNA damage-related proteins, namely, double-stranded DNA breaks (DSBs) biomarker γ-H2AX and ataxia-telangiectasia mutated (ATM), before and after transfection. Results: Compared with 2BS cells, lncRNA NEAT1 was highly expressed in PC-9 cells (P<0.05). The PC-9 cells with lncRNA NEAT1 knock-down were successfully established. After being transfected with siRNA for 12 h, the proliferation of PC-9 cells in siNEAT1 group and siNEAT2 group significantly decreased as compared with the blank control group and the empty transfection group (P<0.05). In the interference groups, cell cycle was arrested in G1 phase ([88.97±2.64]%, [88.15±1.48]% vs [84.5±1.72]%, P<0.05) and G2/M phase ([8.35±2.02]%, [8.11± 1.36]% vs [4.28±1.28]%, P<0.05). The expression levels of DNA damage-related proteinsATM and γ-H2AX in the interference groups were significantly increased (all P<0.05). Conclusion: lncRNA NEAT1 is highly expressed in lung adenocarcinoma PC-9 cells. lncRNA NEAT1 inhibits DNA damage and causes cell cycle at G1/M phase switch, and thus promotes the proliferation of lung adenocarcinoma cells.
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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 (χ = 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.
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Female , Humans , Middle Aged , Cell Line, Tumor , Cell Proliferation , HeLa Cells , Phosphatidylinositol 3-Kinases , Physiology , RNA, Long Noncoding , Physiology , Uterine Cervical Neoplasms , GeneticsABSTRACT
OBJECTIVE: Lung cancer has become the primary cause of cancer‑related death now. New therapies targeting the molecular regulatory machinery were required imperatively. MicroRNAs and long noncoding RNAs can respectively or cooperatively function as oncogenes or tumor suppressor genes in human cancers. The present study identified that miR‑449a was down‑regulated in tissue of human lung cancer. In this study, we aimed to investigate the function of miR‑449a in NL9980 and L9981 lung carcinoma cells lines and the relationship with lncRNA nuclear enriched abundant transcript 1 (NEAT1). MATERIALS AND METHODS: miR‑449a was profiled in several lung carcinoma cell lines by quantitative reverse transcription‑polymerase chain reaction RT‑PCR. We analyzed the effects of miR‑449a overexpression on proliferation, apoptosis and cell cycle in L9981 cells. The regulatory relationship between miR‑449a and NEAT1 was predicted in silico and further studied by miR‑449a inhibitor and mimics assay. RESULTS: miR‑449a was expressed in four cell lines, which we selected, however miR‑449a was in high level in NL9980 and in low level in L9981 (P < 0.05). When the miR‑449a was the overexpression in L9981 cells, the cell growth was suppressed, and the apoptosis cells were promoted compared with the control group (P < 0.05). The G1/G0 became longer and S, G2/M became shorter (P < 0.05) by miR‑449a overexpression. Further study of the interaction between miR‑449a and NEAT1 show that NEAT1 was up‑regulated when cells were transfected with miR‑449a inhibitor, and NEAT1 was down‑regulated when cells transfected with miR‑449a mimics. CONCLUSIONS: Our data indicate that miR‑449a may function as a suppressor of lung cancer, and affects the expression of NEAT1 in lung cancer cells.