lncRNA NORAD Research Articles

Induction of lncRNA NORAD accounts for hypoxia-induced chemoresistance and vasculogenic mimicry in colorectal cancer by sponging the miR-495-3p/ hypoxia-inducible factor-1α (HIF-1α)

ABSTRACT Hypoxic microenvironment represents the hallmark of solid tumors including colorectal cancer (CRC) and facilitates angiogenesis and chemoresistance, leading to poor prognosis. lncRNA NORAD acts as an oncogenic gene to orchestrate cancer progression by regulating cell proliferation and migration. Notably, an emerging study corroborates the elevation of NORAD during hypoxic conditions in pancreatic cancer. Nevertheless, its biological role in hypoxia-evoked CRC remains unclear. Herein, enhanced expression of NORAD and hypoxia-inducible factor-1α (HIF-1α) was validated in CRC tissues. Furthermore, there was a positive association between NORAD and HIF-1α in CRC tissues. CRC cells exposed to hypoxia exhibited a stronger ability to form vasculogenic mimicry (VM) and resistance to 5-fluorouracil (5-FU), concomitant with higher expression of NORAD. NORAD knockdown restrained hypoxia-induced VM formation and VM marker VE-cadherin expression. Moreover, knockdown of NORAD counteracted CRC cell resistance to 5-FU by decreasing cell viability and increasing cell apoptosis. Additionally, NORAD loss reduced hypoxia-induced HIF-1α expression and subsequent epithelial-mesenchymal transition (EMT) by increasing E-cadherin and inhibiting N-cadherin expression. Intriguingly, HIF-1α overexpression reversed NORAD downregulation-mediated inhibition of VM formation and 5-FU resistance. There was a low expression of miR-495-3p in CRC tissues. Furthermore, NORAD could act as a competitive endogenous RNA of miR-495-3p to regulate HIF-1α. Importantly, inhibition of miR-495-3p muted the efficacy of NORAD loss in hypoxia-induced EMT, VM, and chemoresistance. Thus, the current data highlight that NORAD knockdown may antagonize hypoxia-triggered CRC malignancy by suppressing VM formation and chemoresistance by sponging miR-495-3p/HIF-1α to regulate EMT, supporting a promising therapeutic target for refractory hypoxia in CRC.

Long non-coding RNA NORAD protects against cerebral ischemia/reperfusion injury induced brain damage, cell apoptosis, oxidative stress and inflammation by regulating miR-30a-5p/YWHAG

ABSTRACT LncRNAs are identified as critical regulators in cerebral ischemia/reperfusion injury (CIRI). In this current work, SH-SY5Y cells suffered from oxygen-glucose deprivation/reperfusion (OGD/R) were applied to analyze the biological role of lncRNA NORAD and underlying molecular mechanism in CIRI in vitro. Levels of lncRNA NORAD, miR-30a-5p and YWHAG were measured using RT-qPCR. Bioinformatics analysis predicted the binding sites of lncRNA NORAD to miR-30a-5p and miR-30a-5p to YWHAG. Luciferase reporter assay verified the binding relationships among lncRNA NORAD, miR-30a-5p and YWHAG. Additionally, cell viability was determined using CCK-8 assay, and cell apoptosis was assessed using TUNEL staining and western blot analysis. Moreover, the levels of ROS, MDA, LDH and SOD as well as IL-1β, TNF-α, and IL-6 were assessed via application of the corresponding assay kits. Decreased cell viability and temporarily increased lncRNA NORAD level were observed in SH-SY5Y cells after OGD/R. It was demonstrated that lncRNA NORAD regulated YWHAG expression by sponging miR-30a-5p. Upregulation of lncRNA NORAD contributed to the enhancement of cell viability, the inhibition of cell apoptosis as well as the alleviation of oxidative stress and inflammation in OGD/R-injured SH-SY5Y cells, which were reversed upon elevation of miR-30a-5p. In contrast, downregulation of lncRNA NORAD reduced cell viability, promoted cell apoptosis as well as aggravated oxidative stress and inflammation under OGD/R challenge, and the functions of lncRNA NORAD knockdown in OGD/R injury were abolished by upregulation of YWHAG. Taken together, lncRNA NORAD exerted protective effects against OGD/R-induced neural injury by sponging miR-30a-5p to upregulate YWHAG expression.

LncRNA NORAD promotes thyroid carcinoma progression by targeting miR-451.

Long non-coding RNA (lncRNA) NORAD plays an essential role in the development and progress of papillary thyroid carcinoma (PTC). MicroRNA-451 (MiR-451) has been identified as playing an inhibitory role in some types of cancer. However, the molecular mechanism of lncRNA NORAD regulating metastasis of PTC cells by miR-451 has not been fully elucidated. Real-Time quantitative Polymerase Chain Reaction (RT-qPCR) or Western blot analysis of the expression of NORAD, miR-451, and interleukin-6 receptor (IL-6R) in PTC cell lines were carried out. The detection of Luciferase reporter gene showed the relationship between lncRNA NORAD, miR-451 and IL-6R. Cell Counting Kit-8 (CCK-8) assay and transwell assay were performed to detect the influence of lncRNA NORAD, miR-451 on the proliferation, migration, and invasion of PTC cells. The results of RT-qPCR and Western blotting suggested that the expression of lncRNA NORAD and IL-6R were higher than that of the control group, while the expression of miR-451 was lower. Transwell assay indicated that the knockdown of lncRNA NORAD or overexpression of miR-451 significantly inhibited cell proliferation, migration and invasion in PTC cell lines. In addition, lncRNA NORAD negatively controls the expression of miR-451, resulting in the upregulation of IL-6R. IL-6R overexpression can reverse the inhibitory effect of lncRNA NORAD knockdown or miR-451 on PTC cell proliferation and metastasis. Our results indicated that the cell migration and invasion were inhibited by knockdown of lncRNA NORAD or overexpression of miR-451, suggesting that the axis of lncRNA NORAD -miR-451- IL-6R was involved in the development of PTC.

NORAD lentivirus shRNA mitigates fibrosis and inflammatory responses in diabetic cardiomyopathy via the ceRNA network of NORAD/miR-125a-3p/Fyn.

Diabetic cardiomyopathy (DCM) is a serious complication of diabetes, but its pathogenesis is still unclear. This study investigated the mechanism of long noncoding RNA (lncRNA) NORAD in DCM. Male leptin receptor-deficient (db/db) mice and leptin control mice (db/ +) were procured. DCM model was established by subcutaneous injection of angiotensin II (ATII) in db/db mice. NORAD lentivirus shRNA or Adv-miR-125a-3p was administered to analyze cardiac function, fibrosis, serum biochemical indexes, inflammation and fibrosis. Primary cardiomyocytes were extracted and transfected with miR-125a-3p mimic. The competing endogenous RNA (ceRNA) network of NORAD/miR-125a-3p/Fyn was verified. The levels of fibrosis- and inflammation-related factors were measured. In db/db mice treated with ATII, the body weight and serum biochemical indexes were increased, while the cardiac function was decreased, and inflammatory cell infiltration and fibrosis were induced. NORAD was upregulated in diabetic and DCM mice. The 4-week intravenous injection of NORAD lentivirus shRNA reduced body weight and serum biochemical indexes, improved cardiac function, and attenuated inflammation and fibrosis in DCM mice. NORAD acted as a sponge to adsorb miR-125a-3p, and miR-125a-3p targeted Fyn. Intravenous injection of miR-125a-3p adenovirus improved cardiac function and fibrosis and reduced inflammatory responses in DCM mice. Co-overexpression of miR-125-3p and Fyn partly reversed the improving effect of miR-125-3p overexpression on cardiac fibrosis in DCM mice. NORAD lentivirus shRNA improved cardiac function and fibrosis and reduced inflammatory responses in DCM mice via the ceRNA network of NORAD/miR-125a-3p/Fyn. These findings provide a valuable and promising therapeutic target for the treatment of DCM.

Long non-coding RNA NORAD promotes pancreatic cancer stem cell proliferation and self-renewal by blocking microRNA-202-5p-mediated ANP32E inhibition

BackgroundCancer stem cells (CSCs) are key regulators in the processes of tumor initiation, progression, and recurrence. The mechanism that maintains their stemness remains enigmatic, although the role of several long noncoding RNAs (lncRNAs) has been highlighted in the pancreatic cancer stem cells (PCSCs). In this study, we first established that PCSCs overexpressing lncRNA NORAD, and then investigated the effects of NORAD on the maintenance of PCSC stemness.MethodsExpression of lncRNA NORAD, miR-202-5p and ANP32E in PC tissues and cell lines was quantified after RNA isolation. Dual-luciferase reporter assay, RNA pull-down and RIP assays were performed to verify the interactions among NORAD, miR-202-5p and ANP32E. We then carried out gain- and loss-of function of miR-202-5p, ANP32E and NORAD in PANC-1 cell line, followed by measurement of the aldehyde dehydrogenase activity, cell viability, apoptosis, cell cycle distribution, colony formation, self-renewal ability and tumorigenicity of PC cells.ResultsLncRNA NORAD and ANP32E were upregulated in PC tissues and cells, whereas the miR-202-5p level was down-regulated. LncRNA NORAD competitively bound to miR-202-5p, and promoted the expression of the miR-202-5p target gene ANP32E thereby promoting PC cell viability, proliferation, and self-renewal ability in vitro, as well as facilitating tumorigenesis of PCSCs in vivo.ConclusionOverall, lncRNA NORAD upregulates ANP32E expression by competitively binding to miR-202-5, which accelerates the proliferation and self-renewal of PCSCs.

Clinical Significance of the Serum lncRNA NORAD Expression in Patients with Neonatal Sepsis and Its Association with miR-410-3p.

PurposeNeonatal sepsis (NS) is one of the most crucial causes of death in newborns. This investigation aimed to validate the expression level of NORAD and the probable mechanism underlying the function of NORAD in NS.Patients and MethodsThe expression of NORAD and miR-410-3p was identified by qRT-PCR. The diagnostic sensitivity and specificity of NORAD were examined by the ROC curve. The NS cell models were established by the treatment of lipopolysaccharide (LPS) in the macrophage RAW264.7 cells. The luciferase report assay was performed to detect the target relationship between NORAD and miR-410-3p and the association between them was revealed by Pearson correlation.ResultsThe expression of NORAD was at a higher level in the NS group than in the pneumonia controls. The levels of NORAD could sever as a diagnostic marker on discriminating NS patients from pneumonia neonates. The expression of IL-6, IL-8, and TNF-α was enhanced in the macrophage cells under LPS circumstances, while NORAD knockdown reversed the overexpression of these pro-inflammatory cytokines. Besides, miR-410-3p was a possible ceRNA of NORAD by the finding that the luciferase activity fell in the co-transfection of miR-410-3p mimics and WT-NORAD group. In vitro, LPS management could inhibit the expression of miR-410-3p, while silenced NORAD ameliorated the suppressed miR-410-3p levels. Decreased expression of miR-410-3p was discovered in NS patients and the changes of miR-410-3p expression were correlated with the levels of NORAD in the NS patients.ConclusionWe found a raised level of NORAD in the NS patients and it might be a diagnostic indicator for NS patients. NORAD elimination meliorated the inflammation actions steered by LPS. MiR-410-3p was a target of NORAD and lowly expressed in the NS patients.

NORAD-induced Pumilio phase separation is required for genome stability.

Liquid-liquid phase separation is a major mechanism of subcellular compartmentalization1,2. Although the segregation of RNA into phase-separated condensates broadly affects RNA metabolism3,4, whether and how specific RNAs use phase separation to regulate interacting factors such as RNA-binding proteins (RBPs), and the phenotypic consequences of such regulatory interactions, are poorly understood. Here we show that RNA-driven phase separation is a key mechanism through which a long noncoding RNA (lncRNA) controls the activity of RBPs and maintains genomic stability in mammalian cells. The lncRNA NORAD prevents aberrant mitosis by inhibiting Pumilio (PUM) proteins5-8. We show that NORAD can out-compete thousands of other PUM-binding transcripts to inhibit PUM by nucleating the formation of phase-separated PUM condensates, termed NP bodies. Dual mechanisms of PUM recruitment, involving multivalent PUM-NORAD and PUM-PUM interactions, enable NORAD to competitively sequester a super-stoichiometric amount of PUM in NP bodies. Disruption of NORAD-driven PUM phase separation leads to PUM hyperactivity and genome instability that is rescued by synthetic RNAs that induce the formation of PUM condensates. These results reveal a mechanism by which RNA-driven phase separation can regulate RBP activity and identify an essential role for this process in genome maintenance. The repetitive sequence architecture of NORAD and other lncRNAs9-11 suggests that phase separation may be a widely used mechanism of lncRNA-mediated regulation.

LncRNA NORAD regulates scar hypertrophy via miRNA-26a mediating the regulation of TGFβR1/2.

Transforming growth factor-β (TGF-β) pathway presents dysregulation in pathological scarring and mediates hypertrophic scar (HS) formation. The study aims to analyze the potential mechanism of long non-coding RNA NORAD (LncRNA NORAD) and microRNA (miR-26a) regulation of the TGF-β pathway in hypertrophic scar fibroblasts (HSFs). Hypertrophic scar tissues were collected and assayed for LncRNA NORAD, miR-26a, transforming growth factor β receptor I (TGF-βR1) and TGF-βR2, with enzyme-linked immunosorbent assay (ELISA) or qualitative polymerase chain reaction (qPCR). LncRNA NORAD interfering plasmids were transfected into HSFs and induced with TGF-β1. Cell Counting Kit-8 (CCK-8) assays were performed to assess HSF proliferation, and flow cytometry to analyze apoptosis and the cell cycle. TGF-βR1, TGF-βR2, Smad2, and p-Smad2 levels were detected using western blot (WB). The related proteins (p21, cyclin D1 and cyclin-dependent kinase 4 (CDK4)) regulating the cell cycle, and apoptosis-related proteins (caspase-3 and Bcl-2) were also detected using WB. The binding sites of miRNA-26a and LncRNA NORAD, TGF-βR2, or UBE3A were predicted using Starbase and confirmed with dual luciferase reporter assay. RNA immunoprecipitation (RIP) was utilized to explore the interplay of miR-26a with its target genes. LncRNA NORAD is decreased, miR-26a is increased and TGF-β receptors show abnormal expression in scar tissue. LncRNA NORAD knockdown inhibits proliferation of HSF cells induced by TGF-β1 treatment. In addition, cell apoptotic levels are markedly increased and cell numbers in G0/G1 phase are increased. Moreover, the TGF-β/Smad pathway is regulated by decreasing endogenous LncRNA NORAD levels, possibly by affecting the relative levels of TGF-βR1. p21 is notably upregulated, while cyclin D1 and CDK4 are downregulated. Apoptosis-related proteins are significantly affected. LncRNA NORAD may act as a sponge, binding miR-26a and changing its expression. Finally, RIP shows that miR-26a targets the 3'UTRs of TGF-βR2 and UBE3A. LncRNA NORAD regulates HSF proliferation via miR-26a mediating the regulation of TGF-βR2/R1. LncRNA NORAD/miR-26a could be a potential target for treating HS.

LncRNA NORAD, sponging miR-363-3p, promotes invasion and EMT by upregulating PEAK1 and activating the ERK signaling pathway in NSCLC cells.

Lung cancer is one of the most common malignant tumors in the world. Non-small cell lung cancer (NSCLC) accounts for about 80% of all lung cancers. About 75% of patients are in the middle and advanced stages at the time of discovery, and the 5-year survival rate is very low. The aim of this study was to investigate the role of long non-coding RNA (lncRNA) NORAD in the pathogenesis of NSCLC. We found that lncRNA NORAD was highly expressed in human NSCLC tissues and cell lines. The CCK-8 assay results showed that lncRNA NORAD had no effect on cell proliferation. The Transwell assay and Western blotting results showed that overexpression of lncRNA NORAD promoted the invasion and epithelial-mesenchymal transition (EMT) of NSCLC cells. Then bioinformatics analysis was used to screen for candidate miRNA bound with lncRNA NORAD and the target gene of miRNA in NSCLC. The luciferase reporter gene assay and RNA pull-down assay were used to verify the relationship. We found that miR-363-3p expression was down-regulated, whereas PEAK1 expression was upregulated in NSCLC cells. We performed gain and loss function test of lncRNA NORAD, miR-363-3p and PEAK1, the results showed that while miR-363-3p-mimic inhibited cell invasion and EMT by targeting PEAK1, lncRNA NORAD acted as a sponge of miR-363-3p and promoted cell invasion and EMT by increasing the expression of PEAK1. In addition, p-ERK expression was detected by Western blotting to observe the effects of lncRNA NORAD, miR-363-3p and PEAK1 on activation of the ERK signaling pathway. Taken together, lncRNA NORAD upregulated the expression of PEAK1 through sponging miR-363-3p, and then activated the ERK signaling pathway, thereby promoting the development of NSCLC.

LncRNA NORAD accelerates the progression of non-small cell lung cancer via targeting miRNA-455/CDK14 axis.

To explore the potential involvement of long non-coding RNA (lncRNA) NORAD in regulating the progression of Non-small cell lung cancer (NSCLC), and its possible mechanism. Relative level of NORAD in NSCLC tissues and cell lines was determined. Its level in NSCLC patients with different tumor staging (T1-T2, T3-T4) and either with lymphatic metastasis or not was examined as well. Kaplan-Meier curves were depicted for assessing the prognostic value of NORAD in NSCLC. Regulatory effects of NORAD on the proliferative ability of NCI-H1650 and HCC827 cells were evaluated. Dual-luciferase reporter gene assay was conducted to identify the binding between NORAD and miRNA-455, as well as between miRNA-455 and CDK14. At last, the role of NORAD/miRNA-455/CDK14 regulatory loop in influencing the progression of NSCLC was determined. NORAD was upregulated in NSCLC tissues and cells. Its level was higher in NSCLC patients with advanced stage or accompanied with lymphatic metastasis. Worse prognosis was observed in NSCLC patients presenting high level of NORAD. Silence of NORAD attenuated the proliferative ability of NCI-H1650 and HCC827 cells. MiRNA-455 was the downstream target binding to NORAD. Its level was negatively regulated by NORAD. Knockdown of miRNA-455 could reverse the role of NORAD in regulating the proliferative ability of NSCLC. Moreover, CDK14 was the target gene of miRNA-455. CDK14 level was negatively regulated by miRNA-455. LncRNA NORAD is upregulated in NSCLC, which enhances the proliferative ability of tumor cells by targeting miRNA-455/CDK14 axis and thereby accelerates the progression of NSCLC.

LncRNA NORAD promotes bone marrow stem cell differentiation and proliferation by targeting miR-26a-5p in steroid-induced osteonecrosis of the femoral head

BackgroundSteroid-induced osteonecrosis of the femoral head (SONFH) is a devastating orthopedic disease, which seriously affects the quality of life of patients. The study aims to investigate the effects of LncRNA NORAD on SONFH.MethodsHuman bone marrow-derived mesenchymal stem cells (hBMSCs) were isolated from the proximal femur of patients during routine orthopedic surgery and then cultured with dexamethasone (Dex) and transfected with NORAD overexpression vector, siRNA-NORAD and miR-26a-5p mimics. The mRNA expression of NORAD, miR-26a-5p, OPG, RANK, and RANKL was detected by RT-qPCR. Cell proliferation and apoptosis was measured by CCK-8 assay and flow cytometry, respectively. The protein expression of RUNX2, OPG, RANK, and RANKL was detected by western blot. The dual-luciferase reporter gene assay was performed to confirm the binding between NORAD and miR-26a-5p.ResultsNORAD expression was downregulated in SONFH tissues, while miR-26a-5p expression was upregulated. Overexpression of NORAD improved DEX-induced inhibition of proliferation and differentiation, and promotion of apoptosis in hBMSCs, while knockdown of NORAD led to the opposite results. Moreover, NORAD improved DEX-induced inhibition of proliferation and differentiation, and promotion of apoptosis by regulation of miR-26a-5p in hBMSCs.ConclusionsNORAD expression was downregulated in SONFH tissues, while miR-26a-5p expression was upregulated. NORAD improved DEX-induced inhibition of proliferation and differentiation, and promotion of apoptosis by regulation of miR-26a-5p in hBMSCs.

LncRNA NORAD promotes proliferation, migration and angiogenesis of hepatocellular carcinoma cells through targeting miR-211-5p/FOXD1/VEGF-A axis

Introduction and objectivesHepatocellular carcinoma (HCC) is one of the leading causes of cancer-related death around the world. Despite improvement in the prevention and treatment of HCC, the clinical prognosis is still poor with increasing mortality. Non-coding RNAs play pivotal roles in HCC oncogenesis, but the detailed mechanism is poorly known. Therefore, the functions and interaction of lncRNA NORAD and miR-211-5p in HCC was investigated in this study. MethodsQuantitative real-time PCR method was used to analyze the expression of NORAD and miR-211-5p in clinical HCC tissues and cultured cell lines. Knockdown of NORAD and overexpression of miR-211-5p were then carried in HCC cells. Moreover, bioinformatics analysis and luciferase report assays were further employed to analyze the interaction between miR-211-5p and NORAD or FOXD1. ResultsIncreased lncRNA NORAD and decreased miR-211-5p expression were first detected in HCC compared with the peritumorial area. Further studies showed that knockdown of NORAD or overexpression of miR-211-5p impaired the proliferation, migration and angiogenesis of HCC cells. Mechanistically, we found that NORAD functions as a sponge for miR-211-5p. Moreover, it was revealed that decreased miR-211-5p induced the expression of FOXD1 as well as its downstream target VEGF-A, thereby contributes to enhanced angiogenesis of HCC. ConclusionElevated NORAD works as a sponge for miR-211-5p in HCC, thus release the inhibition effect of the latter on its downstream target FOXD1 and VEGF-A, which finally promotes angiogenesis. These results provide new insights into the interaction between NORAD and miR-211-5p in HCC and their potential usage as targets for the development of novel therapeutics against HCC.

NORAD regulates proliferation and apoptosis in cardiomyocytes under high-glucose treatment through miRNA-150-5p/ZEB1 axis.

The purpose of this study was to uncover the potential role of non-coding RNA activated by DNA damage (lncRNA NORAD) in the disease progression of diabetic cardiomyopathy (DCM) and the underlying mechanism. Cell viability, 5-Ethynyl-2'-deoxyuridine (EdU)-positive ratio and apoptotic rate in human cardiomyocyte cell line AC16 undergoing treatment of normal-level (NG) or high-level glucose (HG) were assessed at first. NORAD level in HG-induced AC16 cells at different time points was detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Subsequently, cell viability, EdU-positive ratio, and apoptotic rate in HG-induced AC16 cells overexpressing NORAD were evaluated. Next, subcellular distribution of NORAD was examined, and Dual-Luciferase reporter gene assay was performed to clarify the interaction among NORAD, miRNA-150-5p, and ZEB1. At last, rescue experiments were conducted to clarify the role of NORAD/miRNA-150-5p/ZEB1 axis in influencing the proliferation and apoptosis in HG-induced AC16 cells. Results revealed that HG treatment suppressed the proliferative ability and stimulated apoptosis in AC16 cells. Besides, NORAD was time-dependently downregulated in HG-induced AC16 cells, and it was mainly distributed in cytoplasm. In addition, the overexpression of NORAD enhanced proliferative ability, attenuated apoptosis, and increased Bcl-2/Bax ratio in HG-induced AC16 cells. Finally, NORAD/miRNA-150-5p/ZEB1 axis was verified to protect the malignant progression of DCM. NORAD is upregulated under high-level glucose treatment. Overexpression of NORAD protects DCM development via miRNA-150-5p/ZEB1 axis.

LncRNA NORAD stimulates proliferation and migration of renal cancer via activating the miR-144-3p/MYCN axis.

The purpose of this study was to clarify the potential role of long non-coding RNA (lncRNA) NORAD in the development of renal cancer. Expression levels of NORAD, miR-144-3p, and MYCN in renal cancer tissues and cell lines were detected. After overexpression of NORAD, proliferative and migratory changes in ACHN and A498 cells were evaluated by Cell Counting Kit-8 (CCK-8) and transwell assay, respectively. Thereafter, Luciferase assay was conducted to determine the interaction in the NORAD/miR-144-3p/MYCN axis. Besides, its biological function in influencing phenotype changes of renal cancer cells was finally demonstrated by rescue experiments. The results manifested that NORAD and MYCN were upregulated, while miR-144-3p was downregulated in renal cancer tissues. Overexpression of NORAD stimulated proliferative and migratory potentials in ACHN and A498 cells, which were partially abolished by co-overexpression of miR-144-3p. Moreover, NORAD/miR-144-3p/MYCN axis was found to be responsible for stimulating the malignant development of renal cancer. LncRNA NORAD stimulates proliferative and migratory potentials in renal cancer by sponging miR-144-3p to upregulate MYCN.

LncRNA NORAD targets miR-410-3p to regulate drug resistance sensitivity of osteosarcoma

The current experiment was performed to investigate the effect of LncRNA NORAD on the sensitivity of miR-410-3p to drug resistance of osteosarcoma cells. The cisplatin-resistant cell line HOS/DDP was induced; si-NC, si-NORAD, miR-NC, miR-410-3p, pcDNA-NC, and pcDNA-NORAD were transfected into HOS/DDP cells, respectively; record as a si-NC group, si-NORAD group, miR-NC group, miR-410-3p group, pcDNA-NC group, pcDNA-NORAD group; si-NORAD was co-transfected into HOS/DDP cells with anti-miR-NC, anti-miR-410-3p, recorded as an anti-miR-NC+si-NORAD group and anti-miR-410-3p+si-NORAD group. Real-time quantitative PCR (RT-qPCR) was used to detect LncRNA NORAD, miR-410-3p and multidrug resistance protein 1 (MRP1) mRNA expression levels; Western blot was used to detect cyclin D1 (CyclinD1), MRP1, phosphorylated (p-p65), phosphorylated IкBα (p-IкBα) protein expression; cell counting kit 8 (CCK-8) was used to detect cell viability; dual luciferase report assay to detect targeting relationship between LncRNA NORAD and miR-410-3p. Compared with osteosarcoma cells HOS, the expression levels of LncRNA NORAD, MRP1 mRNA and protein in osteosarcoma resistant cells HOS/DDP were significantly increased, and miR-410-3p expression levels were significantly reduced (P<0.05). Low expression of NORAD or high expression of miR-410-3p, CyclinD1, MRP1 expression levels were significantly reduced, the cell survival rate was significantly reduced, and the half inhibitory concentration of cisplatin was significantly reduced (P<0.05). LncRNA NORAD targets and regulates miR-410-3p, and low expression of miR-410-3p can reverse the effects of low NORAD expression on HOS/DDP cell proliferation and cisplatin resistance. Low expressions of NORAD, p-p65, p-IкBα protein expression levels were significantly reduced; low expression of miR-410-3p could reverse the inhibitory effect of low NORAD expression on p-p65, p-IкBα protein expression. Inhibition of LncRNA NORAD expression can inhibit the proliferation of osteosarcoma HOS/DDP cells through targeted regulation of miR-410-3p, increasing its sensitivity to cisplatin, and it may be related to the NF-κB signaling pathway.

NORAD orchestrates endometrial cancer progression by sequestering FUBP1 nuclear localization to promote cell apoptosis

Long noncoding RNAs (lncRNAs) are emerging as critical regulators in tumor initiation and progression. However, the biological mechanisms and potential clinical application of lncRNA NORAD in endometrial cancer (EC) remain unknown. Herein, we identified NORAD underwent promoter hypermethylation-associated downregulation in EC. Epigenetic inactivation of NORAD was correlated with EC progression (FIGO stage) and poor outcome. Overexpression of NORAD significantly inhibited cell growth and promoted apoptosis in EC cells. Mechanistic studies revealed that multiple regions of NORAD served as a platform for binding with the central domain of anti-apoptotic factor FUBP1. Our findings further indicated that the NORAD/FUBP1 interaction attenuated FUBP1 nuclear localization and thus impaired the occupancies of FUBP1 on its target pro-apoptotic gene promoters, resulting in apoptosis induction in EC. Moreover, knockdown of NORAD promoted tumor growth in the xenograft mice model. While, introduction of NORAD-4 fragment, which bound with FUBP1, successfully reversed tumor growth and apoptosis inhibition mediated by NORAD knockdown in vivo. Our findings provide mechanistic insight into the critical roles of NORAD as a tumor suppressor in EC progression. NORAD could possibly serve as a novel prognostic biomarker and provide the rationale for EC therapy.

LncNORAD interference inhibits tumor growth and lung cancer cell proliferation, invasion and migration by down-regulating CXCR4 to suppress RhoA/ROCK signaling pathway.

Non-small cell lung cancer (NSCLC) accounts for the majority of lung cancer, with an unfavorable prognosis of 5-year survival rates. It is of great clinical significance to further search for more efficacious and novel targets for diagnosis and therapeutic strategies. This study aimed at clarifying the role of long non-coding RNA (lncRNA) NORAD in proliferation, invasion and migration and tumor growth of NSCLC. In this study, mRNA levels of lncRNA NORAD were examined by RT-PCR. CCK-8 assay was applied to test cell viability. Furthermore, wound healing assay and transwell assay were performed to detect the migration and invasion of A549 cells, respectively. Immunohistochemistry was applied to assess the levels of CXC chemokine receptor (CXCR) 4 and CXC chemokine ligand (CXCL) 12. Mice models of NSCLC in vivo were exploited to further examine the potential role of NORAD in tumor growth. Key proteins related to Ras homolog gene family member A (RhoA) GTPase/Rho-associated kinase (RhoA/ROCK) pathway were determined by Western blot. NORAD has elevated the levels in NSCLC tissues and cells. NORAD interference dramatically inhibited tumor growth and suppressed A549 cell proliferation, migration and invasion by downregulating CXCR4 and CXCL12 expression. RhoA/ROCK signaling pathway was activated in NSCLC. This study revealed that the downregulation of lncRNA NORAD could slow down the progression of NSCLC by regulating CXCR4 and RhoA/ROCK signaling pathway.

Downregulation of LncRNA NORAD promotes Ox-LDL-induced vascular endothelial cell injury and atherosclerosis.

Long noncoding RNAs (lncRNAs) play important roles in the development of vascular diseases. However, the effect of lncRNA NORAD on atherosclerosis remains unknown. This study aimed to investigate the effect NORAD on endothelial cell injury and atherosclerosis. Ox-LDL-treated human umbilical vein endothelial cells (HUVECs) and high-fat-diet (HFD)-fed ApoE−/− mice were used as in vitro and in vivo models. Results showed that NORAD-knockdown induced cell cycle arrest in G0/G1 phase, aggravated ox-LDL-induced cell viability reduction, cell apoptosis, and cell senescence along with the increased expression of Bax, P53, P21 and cleaved caspase-3 and the decreased expression of Bcl-2. The effect of NORAD on cell viability was further verified via NORAD-overexpression. NORAD- knockdown increased ox-LDL-induced reactive oxygen species, malondialdehyde, p-IKBα expression levels and NF-κB nuclear translocation. Proinflammatory molecules ICAM, VCAM, and IL-8 were also increased by NORAD- knockdown. Additionally, we identified the strong interaction of NORAD and IL-8 transcription repressor SFPQ in HUVECs. In ApoE−/− mice, NORAD-knockdown increased the lipid disorder and atherosclerotic lesions. The results have suggested that lncRNA NORAD attenuates endothelial cell senescence, endothelial cell apoptosis, and atherosclerosis via NF-κB and p53–p21 signaling pathways and IL-8, in which NORAD-mediated effect on IL-8 might through the direct interaction with SFPQ.

Regulatory mechanism of lncRNA NORAD on proliferation and invasion of ovarian cancer cells through miR-199a-3p.

To explore the regulatory mechanism of lncRNA NORAD on proliferation and invasion of ovarian cancer cells through miR-199a-3p. Eighty-six ovarian cancer tissues and 86 tissues adjacent to cancer, human ovarian cancer cell lines SKOV3, HO-8910, A2780, OVCAR-3, and human normal ovarian epithelial cell line IOSE80 were collected. MiR-199a-3p-mimics, miR-199a-3p-inhibitor, miR-NC, si-NORAD, Sh-NORAD, and NC were transfected into HO-8910 and A2780 cells, the expression levels of lncRNA NORAD and miR-199a-3p in ovarian cancer tissues and cells were detected by qRT-PCR, and the expression levels of N-cadherin, E-cadherin, and vimentin in cells were detected by WB. Cell Counting Kit-8 (CCK-8), transwell, and cell scratch tests were used to detect proliferation, invasion, and migration of cells, and the relationship between lncRNA NORAD and miR-199a-3p was confirmed by the Dual-Luciferase reporter assay. LncRNA NORAD was highly expressed and miR-199a-3p was lowly expressed in ovarian cancer, and the expression levels of LNCRNARAD and miR-199a-3p were negatively correlated. Cell experiments showed that inhibiting the expression of lncRNA NORAD or up-regulating the expression of miR-199a-3p could inhibit the proliferation, invasion, migration, and EMT of ovarian cancer cells, while up-regulating the expression of lncRNA NORAD or inhibiting the expression of miR-199a-3p could promote their proliferation, invasion, migration, and EMT. Dual-Luciferase reporter assay confirmed that there was a regulatory relationship between lncRNA NORAD and miR-199a-3p. LncRNA NORAD was highly expressed in ovarian cancer tissues, while silencing lncRNA NORAD expression could inhibit the proliferation, invasion, migration, and EMT of ovarian cancer cells by regulating miR-199a-3p, which might be a new target for the diagnosis and treatment of ovarian cancer.

The lncRNA NORAD/miR-520a-3p Facilitates Malignancy in Non-Small Cell Lung Cancer via PI3k/Akt/mTOR Signaling Pathway.

Background/AimsThe effects of lncRNA-NORAD/mir-520a-3p on proliferation and invasion of non-small cell lung cancer (NSCLC) were studied, and its potential molecular mechanism was discussed.MethodsqRT-PCR was used to detect the expression of lncRNA NORAD and miR-520a-3p in non-small cell lung cancer tissues and cell lines. CCK-8 method and Transwell test were used to identify the effects of lncRNA NORAD on the proliferation and invasion in NSCLC. Target gene prediction and screening and luciferase reporter assay was used to verify downstream target genes of lncRNA NORAD. The expressions of PI3K, AKT, and mTOR proteins were detected by Western blot.ResultsCompared with normal tissues and cells, the expressions of lncRNA NORAD in cancer tissues and cells were significantly higher. Compared with normal cells, the expression of miR-520a-3p in cells was considerably lower. LncRNA NORAD could accelerate the growth and metastasis of NSCLC in vitro and in vivo. Luciferase reporter assay results indicated that miR-520a-3p was a downstream target gene of lncRNA NORAD. Further findings showed that lncRNA NORAD might bind to miR-520a-3p, thereby affecting the PI3k/Akt/mTOR signaling pathway.ConclusionLncRNA NORAD can regulate the proliferation of NSCLC by regulating miR-520a-3p/PI3k/Akt/mTOR signaling pathway, thus promoting the occurrence and development of NSCLC.