Noncoding RNA Nuclear-enriched Abundant Transcript Research Articles

Tanshinone IIA improves Alzheimer's disease via RNA nuclear-enriched abundant transcript 1/microRNA-291a-3p/member RAS oncogene family Rab22a axis.

Alzheimer's disease (AD) is a neurodegenerative condition characterized by oxidative stress and neuroinflammation. Tanshinone IIA (Tan-IIA), a bioactive compound isolated from Salvia miltiorrhiza plants, has shown potential neuroprotective effects; however, the mechanisms underlying such a function remain unclear. To investigate potential Tan-IIA neuroprotective effects in AD and to elucidate their underlying mechanisms. Hematoxylin and eosin staining was utilized to analyze structural brain tissue morphology. To assess changes in oxidative stress and neuroinflammation, we performed enzyme-linked immunosorbent assay and western blotting. Additionally, the effect of Tan-IIA on AD cell models was evaluated in vitro using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Genetic changes related to the long non-coding RNA (lncRNA) nuclear-enriched abundant transcript 1 (NEAT1)/microRNA (miRNA, miR)-291a-3p/member RAS oncogene family Rab22a axis were assessed through reverse transcription quantitative polymerase chain reaction. In vivo, Tan-IIA treatment improved neuronal morphology and attenuated oxidative stress and neuroinflammation in the brain tissue of AD mice. In vitro experiments showed that Tan-IIA dose-dependently ameliorated the amyloid-beta 1-42-induced reduction of neural stem cell viability, apoptosis, oxidative stress, and neuroinflammation. In this process, the lncRNA NEAT1 - a potential therapeutic target - is highly expressed in AD mice and downregulated via Tan-IIA treatment. Mechanistically, NEAT1 promotes the transcription and translation of Rab22a via miR-291a-3p, which activates nuclear factor kappa-B (NF-κB) signaling, leading to activation of the pro-apoptotic B-cell lymphoma 2-associated X protein and inhibition of the anti-apoptotic B-cell lymphoma 2 protein, which exacerbates AD. Tan-IIA intervention effectively blocked this process by inhibiting the NEAT1/miR-291a-3p/Rab22a axis and NF-κB signaling. This study demonstrates that Tan-IIA exerts neuroprotective effects in AD by modulating the NEAT1/miR-291a-3p/Rab22a/NF-κB signaling pathway, serving as a foundation for the development of innovative approaches for AD therapy.

LncRNA NEAT1 promotes MPP+ induced injury of PC12 cells and accelerates the progression of Parkinson's disease in mice through FUS mediated inhibition of PI3K/AKT/mTOR signalling pathway

Long noncoding RNA nuclear-enriched abundant transcript 1 (NEAT1) is involved in the progression of Parkinson's disease (PD), but the specific regulatory role needs further exploration. This study showed that the expression of NEAT1 was upregulated in the cerebrospinal fluid (CSF) and peripheral blood of patients with different stages of PD. 1-Methyl-4-phenylpyridine (MPP)-treated PC 12 cells were transfected with si-NEAT1, and MPP treatment promoted cell apoptosis, oxidative stress and inflammatory factor secretion. Si-NEAT1 reversed the effects of MPP. NEAT1 silencing eliminated the effect of MPP on the protein expression levels of LC3-II and p62/SQSTM1. By using an online bioinformatics database, Fused in Sarcoma (FUS) was confirmed to be an RNA binding protein of NEAT1, and it was highly expressed in the CSF and peripheral blood of patients with PD. Si-FUS was transfected into MPP-treated PC 12 cells to detect cell apoptosis, oxidative stress, inflammatory factor secretion and autophagy, and the results were the same as those of transfection of si-NEAT1. Furthermore, MPP treatment reduced the phosphorylation levels of PI3K, Akt and mTOR, whereas si-FUS reversed the effects of MPP. In vivo, compared with the model group, the PD mice showed reduced NEAT1 and FUS expression levels and activated PI3K pathway after being injected with si-NEAT1. The brain tissue of NEAT1-silenced PD mice had decreased inflammatory infiltration and apoptosis and increased neurological scores. In conclusion, NEAT1 is involved in PD progression through FUS-mediated inhibition of the PI3K/AKT/mTOR signalling pathway.

Long Non-Coding RNA Nuclear-Enriched Abundant Transcript 1 (NEAT1) Facilitates Foam Cell Formation and Atherosclerosis Progression Through the miR-17-5p/Itchy E3 Ubiquitin Protein Ligase (ITCH)/Liver Kinase B1 (LKB1) Axis.

Foam cell formation is an important step for atherosclerosis (AS) progression. We investigated the mechanism by which the long non-coding RNA (lncRNA) nuclear-enriched abundant transcript 1 (NEAT1) regulates foam cell formation during AS progression.Methods and Results: An in vivo AS model was created by feeding ApoE-/-mice a high-fat diet. Oxidized low-density lipoprotein (ox-LDL)-stimulated macrophages were used as a cellular AS model. Interactions between NEAT1, miR-17-5p, itchy E3 ubiquitin protein ligase (ITCH) and liver kinase B1 (LKB1) were analyzed. NEAT1 and ITCH were highly expressed in clinical samples collected from 10 AS patients and in ox-LDL-treated macrophages, whereas expression of both miR-17-5p and LKB1 was low. ITCH knockdown inhibited ox-LDL-induced lipid accumulation and LDL uptake in macrophages. Mechanistically speakingly, ITCH promoted LDL uptake and lipid accumulation in macrophages by mediating LKB1 ubiquitination degradation. NEAT1 knockdown reduced LDL uptake and lipid accumulation in macrophages and AS progression in vivo. NEAT1 promoted ITCH expression in macrophages by acting as a sponge for miR-17-5p. Inhibition of miR-17-5p facilitated ox-LDL-induced increase in LDL uptake and lipid accumulation in macrophages, which was reversed by NEAT1/ITCH knockdown. NEAT1 accelerated foam cell formation during AS progression through the miR-17-5p/ITCH/LKB1 axis.

The long non-coding RNA NEAT1 promotes the progression of human ovarian cancer through targeting miR-214-3p and regulating angiogenesis

BackgroundAngiogenesis and metastasis contributes substantially to the poor outcome of patients with ovarian cancer. We aimed to explore the role and mechanisms of the long non-coding RNA NEAT1 (nuclear enriched abundant transcript 1) in regulating angiogenesis and metastasis of human ovarian cancer. NEAT1 expression in human ovarian cancer tissues and cell lines including SKOV-3 and A2780 was investigated through in situ hybridization. Gene knockdown and overexpressing were achieved through lentivirus infection, transfection of plasmids or microRNA mimics. Cell viability was measured with the cell counting kit-8 assay, while apoptosis was determined by flow cytometry. Cell migration and invasion were evaluated by transwell experiments, and protein expression was determined by western blot assays or immunohistochemistry. Duo-luciferase reporter assay was employed to confirm the interaction between NEAT1 and target microRNA. In vivo tumor growth was evaluated in nude mice with xenografted SKOV-3/A2780 cells, and blood vessel formation in tumor was examined by histological staining.ResultsNEAT1 was highly expressed in ovarian cancer tissues of patients and cell lines. MiR-214-3p was identified as a sponging target of NEAT1, and they antagonizedeach other in a reciprocal manner. NEAT1-overexpressing SKOV-3 and A2780 cells had significantly increased proliferation, reduced apoptosis, and augmented abilities of migration and invasion, while cells with NEAT1-knockdown displayed markedly attenuated traits of malignancies. Additionally, the levels of NEAT1 appeared to be positively correlated with the expression levels of angiogenesis-related molecules, including Semaphorin 4D (Sema4D), Sema4D receptor Plexin B1, T-lymphoma invasion and metastasis-inducing protein-1 (Tiam1), and Rho-like GTPases Rac1/2/3. In the xenograft mouse model, more NEAT1 expression resulted in faster in vivo tumor growth, more blood vessel formation in tumor tissues, as well as higher expression levels of angiogenesis-related molecules and CD31.ConclusionsNEAT1 promotes angiogenesis and metastasis in human ovarian cancer. NEAT1 and miR-214-3p are promising targets for developing therapeutics to treat human ovarian cancer.

The mechanisms and therapeutic potential of long noncoding RNA NEAT1 in fibrosis.

Fibrosis is the excess deposition of extracellular matrix involved in the pathogenesis of chronic diseases and finally leads to the disruption of tissue architecture and failure of organ function. Long noncoding RNAs (lncRNAs) are a class of RNAs with lengths greater than 200 nucleotides and do not code proteins, which regulate gene expression at multiple levels. Nuclear-enriched abundant transcript 1 (NEAT1) is a long noncoding RNA that is widely expressed in mammalian cells and known as essential architectural scaffold for the formation of paraspeckles. Recently, the accumulating studies demonstrated that lncRNA NEAT1 was remarkable upregulated in the development of fibrosis in different organs, such as liver fibrosis, renal fibrosis, cardiac fibrosis, and lung fibrosis. More importantly, knockdown of NEAT1 remarkably alleviated fibrosis in vitro and in vivo. In this review, we summarized current studies of NEAT1 in fibrosis and hopefully aid in a better understanding of the mechanisms of fibrosis and the potential of NEAT1 as novel therapeutic target for fibrosis.

Targeting lncRNA NEAT1 Impedes Alzheimer’s Disease Progression via MicroRNA-193a Mediated CREB/BDNF and NRF2/NQO1 Pathways

AbstractBackgroundLong noncoding RNA nuclear-enriched abundant transcript 1 (lnc-NEAT1) is closely implicated in neurological or degenerative diseases, while its implication in AD is rarely reported. This study aimed to investigate the effect of lnc-NEAT1 knockdown on neuron injury, inflammation, and oxidative stress in AD, as well as its interaction with downstream targets and pathways.MethodsAPPswe/PS1dE9 transgenic mice were injected with negative control or lnc-NEAT1 interference lentivirus. Besides, AD cellular model was constructed by amyloid β treatment in mice primary neuron cells; then, knockdown of lnc-NEAT1 and microRNA-193a (miR-193a) was performed alone or in combination.ResultsIn vivo experiments revealed that Lnc-NEAT1 knockdown improved cognition in AD mice reflected by Morrison water maze and Y-maze assays. Besides, lnc-NEAT1 knockdown reduced injury and apoptosis, decreased TNF-α and IL-1β levels (indicating lower inflammation level), repressed ROS, MDA but promoted ATP and SOD levels (suggesting lower oxidative stress level), and activated CREB/BDNF and NRF2/NQO1 pathways in hippocampi of AD mice. Notably, lnc-NEAT1 down-regulated miR-193a both in vitro and in vivo; also, it acted as a decoy of miR-193a. In vitro experiments showed that lnc-NEAT1 knockdown decreased apoptosis and oxidative stress, improved cell viability, and also activated CREB/BDNF and NRF2/NQO1 pathways in AD cellular model. Meanwhile, miR-193a knockdown showed the opposite effects, which also attenuated lnc-NEAT1 knockdown-mediated reduction in injury, oxidative stress, and activation of CREB/BDNF and NRF2/NQO1 pathways of AD cellular model.ConclusionLnc-NEAT1 knockdown reduces neuron injury, inflammation, and oxidative stress through activating miR-193a mediated CREB/BDNF and NRF2/NQO1 pathways in AD.FundingNo Funding

LncRNA NEAT1 accelerates renal fibrosis progression via targeting miR-31 and modulating RhoA/ROCK signal pathway.

Renal fibrosis is the final pathway for chronic kidney disease to end-stage renal failure. Noncoding RNAs have been reported to play a crucial role in renal fibrosis. Here, the effects of long noncoding RNA (lncRNA) nuclear-enriched abundant transcript 1 (NEAT1) and miR-31 on renal fibrosis and their regulatory mechanism were evaluated. RT-qPCR was used to assess NEAT1, miR-31, and RhoA levels. Western blot was performed to analyze the expression of fibrosis markers, RhoA, rho-related kinase (ROCK1), and connective tissue growth factor (CTGF). RNA immunoprecipitation (RIP), fluorescence in situ hybridization (FISH), and luciferase reporter assays verified the interaction between miR-31 and NEAT1 or RhoA. Renal fibrosis and injury were observed by Masson and hematoxylin and eosin (H&E) staining. The expression level of inflammatory cytokines was detected by ELISA. Immunohistochemistry (IHC) was performed to examine the expression levels of α-smooth muscle actin (α-SMA) and RhoA in renal tissues. We showed that NEAT1 was highly expressed, whereas miR-31 was decreased in renal fibrosis. NEAT1 was found to directly bind miR-31 to positively regulate RhoA expression. Furthermore, NEAT1 silencing inhibited renal fibrosis and inflammation and suppressed the RhoA/ROCK1 signaling pathway. However, knockdown of miR-31 could reverse these effects. NEAT1 silencing or overexpression of miR-31 alleviated renal fibrosis in vivo. In conclusion, NEAT1 accelerates renal fibrosis progression via negative regulation of miR-31 and the activation of RhoA/ROCK1 pathway, thereby upregulating the expression level of CTGF, providing a theoretical basis for treatment and prognostic evaluation of renal fibrosis.

Long non‑coding RNA NEAT1 promotes mouse granulosa cell proliferation and estradiol synthesis by sponging miR‑874‑3p.

It has been reported that long non-coding RNA nuclear-enriched abundant transcript 1 (NEAT1) is involved in follicular growth and multiple ovarian diseases, but not the physiological function of NEAT1 in mouse granulosa cells (mGCs). Therefore, the aim of the present study was to investigate the biological roles and regulatory mechanisms of NEAT1 in mGCs. The biological effects of NEAT1 on mGCs proliferation, apoptosis, production of 17β-Estradiol (E2) and progesterone (P4) were investigated using MTS, flow cytometry and enzyme-linked immunosorbent assays, respectively. The association between NEAT1 and microRNA (miR)-874-3p was verified using luciferase reporter assay and RNA immunoprecipitation analysis. The results demonstrated that the knockdown of NEAT1 in mGC cells significantly promoted mGCs cell proliferation, inhibited apoptosis and increased the production of E2 and P4 in mGCs. The interference-mediated effect of NEAT1 on mGCs could be partially reversed by the downregulation of miR-874-3p. Overall, these results indicated that NEAT1 served as a competing endogenous RNA by competitively binding with miR-874-3p, thereby modulating mGCs proliferation and the production of E2 and P4 in mGCs.

Gambogenic acid antagonizes the expression and effects of long non-coding RNA NEAT1 and triggers autophagy and ferroptosis in melanoma

In this study, we investigated the molecular mechanism underlying melanoma proliferation, with the aim to discover effective interventions which may markedly improve clinical prognosis. The results showed that gambogenic acid (GNA) could inhibit the proliferation of melanoma cells in vivo (C57BL/6 mice) and in vitro. Long non-coding RNA sequencing was used to identify the most significant long non-coding RNA, i.e., nuclear enriched abundant transcript 1 (NEAT1). NEAT1 was is up-regulated in melanoma, which was found to closely relate to cell proliferation. Melanoma cell lines either over-expressing NEAT1 or with NEAT1 knockdown was established through cloning experiments. A model of transplanted tumors was established to verify the inhibitory effect of GNA on the proliferation of melanoma cells in vitro and in vivo by downregulating NEAT1. Downregulation of NEAT1-induced ferroptosis and autophagy was demonstrated by detecting the effects of NEAT1 overexpressed and downregulated melanoma cell lines and melanoma transplantation model mice. Mechanistically, downregulation of NEAT1 can weaken the direct binding of Slc7a11, indirectly leading to inhibiting GPX-4 activity and subsequent ferroptosis, while, mediating the AMPK/mTOR signal axis-induced autophagy. The levels of Furthermore, NEAT1 decrease under the treatment of Gambogenic acid (GNA), a promising natural anticancer compound, while NEAT1 overexpression suppresses GNA inhibition on cell vitality and eliminates GNA-induced melanoma cell ferroptosis and autophagy.

Long noncoding RNA NEAT1 decreases polycystic ovary syndrome progression via the modulation of the microRNA-324-3p and BRD3 axis.

Long noncoding RNA nuclear-enriched abundant transcript 1 (NEAT1) is believed to be involved in many gynecological and obstetrics disorders. Nevertheless, the role of NEAT1 in polycystic ovary syndrome (PCOS) is scarcely investigated. Our study aimed to investigate the role of NEAT1, microRNA (miR)-324-3p, and bromodomain containing 3 (BRD3) in PCOS. First, 80 women with PCOS and 80 healthy (non-PCOS) women were included, and their serum hormone levels were tested. Next, thePCOS mouse model was established by dehydroepiandrosterone injection, and then NEAT1, miR-324-3p, and BRD3 expression levels were detected in the PCOS mice. Lentivirus carrying short hairpin-NEAT1 or miR-324-3p agomir was injected into the PCOS mice to determine the change in biochemical indices and pathology. Moreover, a rescue experiment was conducted, after which, the binding relationships among NEAT1, miR-324-3p, and BRD3 were analyzed. NEAT1 and BRD3were expressed at a high level while miR-324-3p was expressed at a low level in women with PCOS and PCOS mice. Reduced levels of NEAT1 or elevated levels of miR-324-3p mitigated metabolic disorders and alleviated ovarian pathological changes in PCOS mice. Mechanistically, NEAT1 sponged miR-324-3p and miR-324-3p targeted BRD3. In the rescue experiment, elevated miR-324-3p or reduced BRD3 level reversed the effects of the enhanced NEAT1 on metabolic disorders and ovarian pathological changes in PCOS mice. NEAT1 exacerbates metabolic disorders and ovarian pathological changes in PCOS mice by downregulating miR-324-3p and upregulating BRD3. This study gives a novel direction in PCOS treatment.

Long Noncoding RNA NEAT1 Expression and Its Target miR-124 in Diabetic Ischemic Stroke Patients.

Background: Diabetes mellitus is a known risk factor for stroke and may be linked to poorer post-stroke outcomes. However, the underlying molecular mechanisms remain to be fully identified. In this study we assessed the association of the lncRNA Nuclear enriched abundant transcript 1 (NEAT1)'s expression and its target miRNA-124 with acute ischemic stroke (AIS) in type II diabetic patients (T2DM). Methods and Results: Diabetic patients with stroke, non-diabetics with stroke, diabetics without stroke, and controls were recruited. NEAT1 and miR-124 expression levels in plasma samples from the participants were investigated using real-time reverse transcription-polymerase chain reaction (RT-qPCR). C reactive protein (CRP) and tumor necrosis factor alpha (TNF-α) were measured using an enzyme linked immunosorbent assay (ELISA) technique. In the DM+AIS group, NEAT1 expression was considerably higher, compared with AIS group and with control group. In comparison to the AIS-only patients, DM patients and controls, miR-124 expression was considerably lower in the DM+AIS group. NEAT1 was shown to have good predictive value for AIS risk in diabetics, based on Receiver Operating Characteristic (ROC) curve analysis. In both the DM+AIS and the AIS group, NEAT1 levels was strongly linked with the National Institutes of Health Stroke Scale (NIHSS) score. Also, a significant positive correlation was observed between NEAT1 expression and the inflammatory markers CRP and TNF-α and significant negative association with miRNA-124 in patient groups. Conclusion: In diabetic patients, the lncRNA NEAT1 may influence the incidence, severity, inflammation, and prognosis of AIS. NEAT1 expression levels could be used as a diagnostic marker of stroke in diabetic patients.

Expression relationship and significance of NEAT1 and miR-27a-3p in serum and cerebrospinal fluid of patients with Alzheimer’s disease

ObjectiveTo explore the expression relationship and significance of long chain non-coding RNA nuclear-enriched abundant transcript 1 (LncRNA NEAT1) and miR-27a-3p in serum and cerebrospinal fluid of patients with Alzheimer’s disease (AD).MethodsSixty-six AD patients received by the Department of Neurology of our hospital from October 2019 to September 2021 were gathered, according to the Clinical Dementia Rating Scale (CDR) score, they were grouped into mild group (≤1 point, n = 41) and moderate-to-severe group (> 1 point, n = 25). Another 32 cases of serum and cerebrospinal fluid samples from outpatient physical examination personnel were regarded as the control group. The general materials on all subjects was recorded and cognition was assessed;real-time quantitative PCR was performed to measure the expression levels of miR-27a-3p and NEAT1 in serum and cerebrospinal fluid;enzyme-linked immunosorbent assay was performed to measure the protein levels of β-amyloid precursor protein cleaving enzyme 1 (BACE1), β-amyloid (Aβ) 40 and Aβ42 in cerebrospinal fluid;Spearman’s method was performed to analyze the correlation of serum miR-27a-3p and NEAT1 levels with MMSE and MoCA scores;Pearson method was performed to analyze the correlation between serum miR-27a-3p and NEAT1 levels and Aβ deposition standard uptake value ratio (SUVR) and cerebrospinal fluid miR-27a-3p, NEAT1, BACE1, Aβ42 and Aβ40 levels.ResultsThe MMSE score, MoCA score, serum miR-27a-3p level, cerebrospinal fluid miR-27a-3p, Aβ42 levels and Aβ42/Aβ40 ratio of AD patients in mild group and moderate-to-severe group were all lower than those in the control group, and the moderate-to-severe group were lower than the mild group (all P < 0.05);the serum NEAT1 level, SUVR, and cerebrospinal fluid NEAT1 and BACE1 levels were higher than those in the control group, and the moderate-to-severe group were higher than the mild group (all P < 0.05). Serum NEAT1 level in AD patients was positively correlated with SUVR, cerebrospinal fluid NEAT1 and BACE1 (r = 0.350, 0.606, 0.341, all P < 0.05);serum miR-27a-3p level was positively correlated with cerebrospinal fluid miR-27a-3p level (r = 0.695, P < 0.05), and negatively correlated with SUVR and cerebrospinal fluid BACE1 level (r = − 0.521, − 0.447, both P < 0.05).ConclusionsThe expression trends of NEAT1 and miR-27a-3p in the serum and cerebrospinal fluid of AD patients are consistent, the level of NEAT1 is increased, and the level of miR-27a-3p is decreased. The levels of the two are negatively correlated, which is related to the degree of Aβ deposition in the brain of AD patients and is involved in the progression of AD.

Long non-coding RNA nuclear enriched abundant transcript 1 (NEAT1) modulates inhibitor of DNA binding 1 (ID1) to facilitate papillary thyroid carcinoma development by sponging microRNA-524-5p

ABSTRACT Long non-coding RNA (lncRNA) nuclear-enriched abundant transcript 1 (NEAT1) exerts a pro-oncogenic role in several cancers, whereas its underlying regulatory mechanism in papillary thyroid carcinoma (PTC) progression remains unknown. This research mainly explored the roles of NEAT1 in PTC development. Quantitative real-time polymerase-chain reaction (qRT-PCR) was applied to measure NEAT1, miR-524-5p, and inhibitor of DNA binding 1 (ID1) expression in PTC tissues and cells. Western blot was conducted for detecting the protein levels. MTT, transwell, and flow cytometry assays were applied to assess cell proliferation, metastasis, and apoptosis in PTC cells in vitro. The PTC xenograft tumor model was used for investigating the role of NEAT1 in vivo. Dual-luciferase reporter assay was utilized for confirming the interaction between miR-524-5p and NEAT1 or ID1. In PTC tissues and cells, NEAT1 was significantly up-regulated. NEAT1 silencing blocked cell proliferation, metastasis, and facilitated apoptosis in vitro and impeded xenograft tumor growth in vivo. Bioinformatics prediction revealed the existence of binding sites between NEAT1 and miR-524-5p. Besides, ID1 was confirmed as a direct target to miR-524-5p, and the enhancement of ID1 reversed the regulation of miR-524-5p upregulation on cell progression. In addition, NEAT1 promoted PTC development by regulating ID1 expression via sponging miR-524-5p in PTC. In summary, we demonstrate that NEAT1 advanced the process of PTC by miR-524-5p/ID1 axis, which may enhance our comprehension of PTC pathogenesis.

Long non-coding RNA NEAT1 participates in ventilator-induced lung injury by regulating miR-20b expression.

Long non-coding (lnc)RNA nuclear enriched abundant transcript 1 (NEAT1) has been reported to serve an important role in cancer, but its effects on ventilator-induced lung injury (VILI) remain unclear. The present study aimed to investigate the role of lncRNA NEAT1 in alveolar macrophages (AMs) on ventilator-induced lung injury (VILI). Mouse and cell models were established to detect NEAT1 expression, pathological changes in lung tissues, apoptosis of AMs, expression of the M1 phenotype marker, CD86 and M2 phenotype marker, CD206, and the expression levels of interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α and inducible nitric oxide synthase (iNOS). The associations between NEAT1, microRNA (miRNA/miR)-20b and STAT3 were predicted using StarBase and TargetScan, and verified via the dual-luciferase reporter and RIP assays. NEAT1 short hairpin RNA and miR-20b inhibitor were co-transfected into AMs to assess the effect of NEAT1 and miR-20b in VILI. The results demonstrated that NEAT1 was highly expressed in lung tissues of VILI mice and cell stretch (CS) treated AMs. Furthermore, NEAT1 knockdown inhibited lung injury and cell apoptosis induced by VILI. Compared with VILI mice or CS-treated AMs, NEAT1 knockdown accelerated the phenotypic transformation from M1 to M2, and decreased the expression levels of IL-1β, IL-6, TNF-α and iNOS. Notably, miR-20b was identified as the target of NEAT1, and STAT3 was the target of miR-20b. NEAT1 knockdown decreased STAT3 protein expression, the effects of which were reversed following transfection with miR-20b inhibitor. Furthermore, the protective effect of NEAT1 knockdown on VILI was reversed following transfection with miR-20b inhibitor. Taken together, the results of the present study suggest that NEAT1 knockdown promotes phenotypic transformation of AMs from M1 to M2 and alleviates lung injury and apoptosis of VILI by regulating miR-20b expression.

Long non-coding RNA nuclear-enriched abundant transcript 1 (LncRNA NEAT1) upregulates Cyclin T2 (CCNT2) in laryngeal papilloma through sponging miR-577/miR-1224-5p and blocking cell apoptosis

ABSTRACT Long non-coding RNA nuclear-enriched abundant transcript 1 (Lnc-NEAT1) is a crucial mediator in cancer progression, which is associated with poor prognosis of patients with laryngeal papilloma (LP). Herein, we aimed to determine how Lnc-NEAT1 promotes LP development. q-PCR, MTT, EDU and Western blotting were performed to determine that Lnc-NEAT1 facilitates LP cell proliferation and hinders cell apoptosis. LncBase database, q-PCR, GEPIA online database, Dual luciferase reporter and RIP assays were utilized to confirm that Lnc-NEAT1 sponged miR-577/miR-1224-5p and negatively mediated CCNT2. Western blotting, MTT and EDU were used to confirm that Lnc-NEAT1 promoted LP cell proliferation and inhibited cell apoptosis through CCNT2. Lnc-NEAT1 was highly expressed in LP, and enhanced LP cell proliferation, and it was inhibited by Lnc-NEAT1 depleting. Concerning the underlying mechanism, it was found that Lnc-NEAT1 could functionally sponge microRNA-577 (miR-577) and microRNA-1224-5p (miR-1224-5p) and up-regulate Cyclin T2 (CCNT2) in LP cells. Notably, CCNT2 knockdown blocked Lnc-NEAT1-induced LP cell proliferation, and rescued cell apoptosis, which was specifically indicated by restoration of Bax, Cleaved caspase 3 and Cleaved caspase 9. Lnc-NEAT1 played a carcinogenic role in LP through mediating miR-577 or miR-1224-5p/CCNT2 axis, which may provide promising insights for the treatment of LP.

Downregulation of lncRNA NEAT1 inhibits the proliferation of human cutaneous squamous cell carcinoma in vivo and in vitro.

BackgroundThe incidence of cutaneous squamous cell carcinoma (CSCC), a malignant tumor that threatens human life, is increasing every year, and yet its pathogenesis is still unclear. This study found that long noncoding RNA (lncRNA) nuclear-enriched abundant transcript 1 (NEAT1) was abnormally expressed in CSCC. However, the biochemical mechanisms of lncRNA NEAT1 in carcinogenesis and the development of cancer remain unclear.MethodsFluorescence quantitative polymerase chain reaction (qPCR) was conducted to determine lncRNA NEAT1 expression in CSCC and paracarcinoma tissues and investigate the correlation between NEAT1 levels and patients’ clinicopathological features. The invasion, proliferation, and migration of CSCC cells were measured using colony formation, Cell Counting Kit-8, and Transwell assays. Western blot assay was conducted to test whether NEAT1 knockdown affected invasion and migration-related proteins. In addition, a nude mouse subcutaneous tumorigenesis experiment was performed to determine whether the knockdown of NEAT1 affected the proliferation ability of CSCC cells.ResultsChanges in lncRNA NEAT1 expression in CSCC tissues were correlated with the degree of lymph node metastasis and the tumor, regional lymph nodes, and distant metastasis (TNM) grade of patients. The downregulation of NEAT1 lncRNA significantly impeded cell invasion, proliferation, and migration in CSCC. Through lncRNA NEAT1 knockdown, significant reductions in metalloproteinase-2, metalloproteinase-9, N-cadherin, and vimentin expression were observed, and the level of E-cadherin increased. In vivo experiments in nude mice revealed that knockdown of lncRNA NEAT1 greatly inhibited cell proliferation in CSCC.ConclusionsIn CSCC tissues, NEAT1 lncRNA was expressed at high levels and correlated with lymph node metastasis and TNM stage. The knockdown of NEAT1 lncRNA could significantly impede CSCC proliferation, metastasis, and invasion. Additionally, by measuring the expression level of lncRNA NEAT1, we may be able to detect the clinical and pathological characteristics of CSCC.

Long noncoding RNA NEAT1 changes exosome secretion and microRNA expression carried by exosomes in hepatocellular carcinoma cells.

This study aimed to investigate the roles and functions of nuclear-enriched abundant transcript 1 (NEAT1) in exosome secretion and exosomal microRNA (miRNA) changes in hepatocellular carcinoma (HCC) cells. HepG2 and HuH-7 cells were divided into two groups: Lv-control (which were infected with lentivirus without NEAT1 expression) and Lv-NEAT1 (which were infected with lentivirus with NEAT1 overexpression). Each group was used to study cell function (proliferation, invasion, and apoptosis) and exosome secretion by nanoparticle tracking analysis (NTA), electron microscopy, and nanoflow cytometry (nanoFCM). Different levels of messenger RNA (mRNA), miRNA, and exosomal miRNA were detected by RNA sequencing. Next, potential target RNAs were verified by reverse transcription polymerase chain reaction (RT-PCR). Changed exosomal miRNAs were found and miRNA mimics were used to study cell function in NEAT1-overexpression and NEAT1-knockdown HCC cells. The data showed that NEAT1-overexpression promoted exosome secretion. The overexpression of NEAT1 altered global genes, including exosome-related genes. Compared with the control group, we observed that several miRNAs changed in the exosomes secreted by NEAT1-overexpressing cells. Our study found that these changed exosomal miRNAs played a suppressor role in HCC. Transfection of miR-634, miR-638, and miR-3960 reversed the enhanced invasion and proliferation in HCC cells with a high level of NEAT1 expression. These results suggested that NEAT1 regulates exosome-related genes, which might be associated with increasing exosome secretion by NEAT1-overexpressing cells. Furthermore, NEAT1 promotes cell invasion and proliferation via downregulation of miR-634, miR-638, and miR-3960 in exosomes. This study may provide potential targets for exosome-mediated miRNA transfer in HCCs with a high level of NEAT1 expression therapy.

LncRNA NEAT1 Recruits SFPQ to Regulate MITF Splicing and Control RPE Cell Proliferation.

PurposeRetinal pigment epithelium (RPE) cell proliferation is precisely regulated to maintain retinal homoeostasis. Microphthalmia-associated transcription factor (MITF), a critical transcription factor in RPE cells, has two alternatively spliced isoforms: (+)MITF and (−)MITF. Previous work has shown that (−)MITF but not (+)MITF inhibits RPE cell proliferation. This study aims to investigate the role of long non-coding RNA (lncRNA) nuclear-enriched abundant transcript 1 (NEAT1) in regulating MITF splicing and hence proliferation of RPE cells.MethodsMouse RPE, primary cultured mouse RPE cells, and different proliferative human embryonic stem cell (hESC)–RPE cells were used to evaluate the expression of (+)MITF, (−)MITF, and NEAT1 by reverse-transcription PCR (RT-PCR) or quantitative RT-PCR. NEAT1 was knocked down using specific small interfering RNAs (siRNAs). Splicing factor proline- and glutamine-rich (SFPQ) was overexpressed with the use of lentivirus infection. Cell proliferation was analyzed by cell number counting and Ki67 immunostaining. RNA immunoprecipitation (RIP) was used to analyze the co-binding between the SFPQ and MITF or NEAT1.Results NEAT1 was highly expressed in proliferative RPE cells, which had low expression of (−)MITF. Knockdown of NEAT1 in RPE cells switched the MITF splicing pattern to produce higher levels of (−)MITF and inhibited cell proliferation. Mechanistically, NEAT1 recruited SFPQ to bind directly with MITF mRNA to regulate its alternative splicing. Overexpression of SFPQ in ARPE-19 cells enhanced the binding enrichment of SFPQ to MITF and increased the splicing efficiency of (+)MITF. The binding affinity between SFPQ and MITF was decreased after NEAT1 knockdown.Conclusions NEAT1 acts as a scaffold to recruit SFPQ to MITF mRNA and promote its binding affinity, which plays an important role in regulating the alternative splicing of MITF and RPE cell proliferation.

Long Non-Coding RNA NEAT1 Knockdown Alleviates Rheumatoid Arthritis by Reducing IL-18 through p300/CBP Repression.

Rheumatoid arthritis (RA) is chronic inflammatory autoimmune disease. The crucial role of long non-coding RNA (lncRNA) in the progression of RA has been highlighted. Hence, this study was designed to explore the specific downstream mechanism of lncRNA nuclear-enriched abundant transcript 1 (NEAT1) in RA. Initially, the expression of NEAT1, p-p65, p300, and IL-18 in clinical tissues and cells was determined. Then, interactions among p65, NEAT1, p300, CBP, and IL-18 were investigated by immunofluorescence staining, dual luciferase reporter gene assay, RT-qPCR assay ChIP assay, and RIP assay followed by the analysis of their effects on RA in vivo and in vitro after expression alteration. The expressions of NEAT1, p-p65, p300, and IL-18 were all upregulated in the synovial tissues from the mice and patients with RA. NEAT1 silencing reduced the infiltration of CD4+ T cells and macrophages in synovial tissues, downregulated expression of blood inflammatory factors, relieved RA severity, and lowered incidence of RA in mice. Further, p-p65 could increase the expression of NEAT1 by binding to the NEAT1 promoter region, NEAT1 could co-locate and interact with p300, thus regulating the expression of IL-18 by regulating histone acetylation modification in IL-18 promoter region. NEAT1 aggravated RA via p300/CBP/IL-18 axis, representing a promising therapeutic target in RA.

Long non-coding RNA NEAT1 contributes to lipopolysaccharide-induced inflammation and apoptosis of human middle ear epithelial cells via regulating the miR-301b-3p/TLR4 axis.

Acute otitis media (AOM) is a common infectious disease in children that is accompanied by signs and symptoms of middle ear inflammation and infection. Previous studies have shown that the long non-coding (lnc)RNA nuclear-enriched abundant transcript 1(NEAT1) participates in various inflammatory conditions and plays an important regulatory role. The focus of the present study was the biological function of NEAT1 and underlying molecular mechanism in lipopolysaccharide (LPS)-induced human middle ear epithelial cells (HMEECs). The expression of NEAT1, miR-301b-3p and toll-like receptor 4 (TLR4) protein were determined by reverse transcription-quantitative PCR and western blot assays, respectively. Dual-luciferase reporter assay was performed to investigate the combination of miR-301b-3p and NEAT1 or TLR4. In addition, cell viability, apoptosis and the levels of pro-inflammatory factors (IL-1β, TNF-α and IL-6) were measured by Cell Counting Kit-8 assay, flow cytometry and ELISA, respectively. Cell viability was significantly decreased, whereas apoptosis and inflammation were increased in LPS-stimulated HMEECs. Functional analyses demonstrated that NEAT1 was upregulated following LPS treatment, whereas knockdown of NEAT1 significantly increased cell viability and alleviated apoptosis and inflammation. Mechanistically, NEAT1 directly bound to and negatively regulated miR-301b-3p expression, whereas miR-301b-3p inhibitors abolished the inhibitory effect of NEAT1 knockdown on cell apoptosis and inflammation. As a target of miR-301b-3p, TLR4 was regulated by NEAT1 and miR-301b-3p. TLR4 overexpression alleviated NEAT1 silencing-induced inflammatory suppression. Rescue experiments demonstrated that NEAT1 promoted TLR4 expression by inhibiting miR-301b-3p. Collectively, the results of the present study suggested that NEAT1 may attenuate LPS-induced inflammation and apoptosis in HMEECs by modulating the miR-301b-3p/TLR4 axis, and may provide a new therapeutic target for the clinical treatment of AOM.