Expression Of Growth Arrest-specific 5 Research Articles

The lncRNA GAS5 upregulates ANXA2 to mediate the macrophage inflammatory response during atherosclerosis development

Inflammatory macrophages play a crucial role in atherosclerosis development. The long non-coding RNA growth arrest-specific 5 (GAS5) regulates THP-1 macrophage inflammation by sponging microRNAs. The purpose of this study was to investigate the regulatory mechanism of GAS5 in atherosclerosis development. GSE40231, GSE21545, and GSE28829 datasets from the Gene Expression Omnibus database were integrated after adjusting for batch effect. Differential analysis was performed on the integrated dataset and validated using the Genotype-Tissue Expression and GSE57691 datasets. Potential biological functions of GAS5 and annexin A2 (ANXA2) were identified using gene set enrichment analysis (GSEA). ssGSEA, CIBERSORTx, and ImmuCellAI algorithms were used to identify immune infiltration in plaque samples. GAS5 and ANXA2 expression levels in RAW264.7 cells treated with oxidized low-density lipoprotein (ox-LDL) were measured by qRT-PCR and Western blot. Small interfering and short hairpin RNA were used to silence GAS5 expression. Plasmids of ANXA2 were used to establish ANXA2 overexpression. Apoptosis and inflammatory markers in macrophages were detected by Western blot. Aortic samples from APOE−/− mice were collected to validate the expression of GAS5 and ANXA2. GAS5 expression was significantly increased during atherosclerosis. GAS5 expression was positively correlated with macrophage activation and ANXA2 expression in plaques. Furthermore, ANXA2 upregulation was also related to the activation of macrophage. GSEA indicated similar biological functions for GAS5 and ANXA2 in plaques. Moreover, in vitro experiments showed that both GAS5 and ANXA2 contributed to macrophage apoptosis and inflammation. Rescue assays revealed that the inflammatory effects of GAS5 on macrophages were ANXA2-dependent. In vivo experiments confirmed the highly expression of Gas5 and Anxa2 in the plaque group. We identified the atherogenic roles of GAS5 and ANXA2 in the inflammatory response of macrophages. The inflammatory response in ox-LDL-treated macrophages was found to be mediated by GAS5-ANXA2 regulation, opening new avenues for atherosclerosis therapy.

Block Copolymer Nanomicelle-Encapsulated Curcumin Attenuates Cerebral Ischemia Injury and Affects Stem Cell Marker Expression by Inhibiting lncRNA GAS5.

Stroke has become the most common cause of death among residents in China, among which ischemic stroke accounts for the vast majority reaching 70% to 80%. It is of great importance to actively investigate the protective mechanism of cerebral ischemia injury after IS (ischemic stroke). We constructed cerebral ischemia injury models in vivo MACO rat and in vitro (oxygen-glucose deprivation cell model) and set up different interference groups. RT-PCR (reverse transcription PCR) was conducted to detect the expression of lncRNA in neuronal cells, brain tissue, and plasma of different groups, and ELISA (enzyme-linked immunosorbent assay) and western blot were used to detect the expression of the protein in neuronal cells, brain tissue, and plasma of different groups. Cell activity was detected by the CCK-8 assay, while cell apoptosis was examined by TUNEL (terminal deoxynucleotidyl transferase dUTP nick end labeling) assay. In the rats' neuronal cells and brain tissue, curcumin can inhibit the expression of lncRNA GAS5 (long noncoding RNA growth arrest-specific 5). In oxygen-glucose-deprived neuronal cells in vitro, curcumin and low-expressed lncRNA GAS5 can enhance cell activity and decline cell apoptosis, but the addition of curcumin and overexpressed lncRNA GAS5 can make this phenomenon disappear. In neuronal cells, plasma, and brain tissue, curcumin and the low-expressed lncRNA GAS5 can inhibit the expression of IL-1β (interleukin 1 beta), TNF-α (tumor necrosis factor alpha), IL-6 (interleukin 6), Sox2 (SRY-box transcription factor 2), Nanog, and Oct4 (octamer-binding transcription factor 4). However, overexpressed lncRNA GAS5 and curcumin made the inhibitory effect disappear. In conclusion, this study demonstrated that curcumin could inhibit the expression of lncRNA GAS5, thereby inhibiting the expression of inflammation-related factors IL-1β, TNF-α, and IL-6, and ultimately achieve the purpose of attenuating cerebral ischemic cell damage. However, curcumin and lncRNA GAS5 may not alleviate cerebral ischemic cell damage by affecting stem cell differentiation.

LncRNA GAS5 suppression of the malignant phenotype of ovarian cancer via the miR-23a-WT1 axis.

Growth arrest-specific 5 (GAS5) is a long noncoding RNA (lncRNA) that regulates cell viability. GAS5 lncRNA has been shown to decrease colorectal and breast cancer carcinogenesis. Although the function and mechanisms related to lncRNA GAS5 in the development of ovarian cancer (OC) remains unclear. The goal of this study was to clarify the essential functions of lncRNA GAS5 in regulating OC progression and its underlying mechanism. Relative levels of lncRNA GAS5 in OC and normal ovarian tissues were identified by quantitative real-time polymerase chain reaction (qRT-PCR). The regulatory effects of lncRNA GAS5 on the proliferation and apoptosis of SK-OV-3 cells were evaluated. Moreover, bioinformatics tools were used to predict a novel target [microRNA (miRNA)] of lncRNA GAS5. To explore the key functions of the lncRNA GAS5/miRNA-23a/WT1 regulatory loop in mediating OC progression, we performed functional experiments and a dual-luciferase reporter (DLR) gene assessment. Downregulation of lncRNA GAS5 was found in tissues of OC, which was positively correlated with a poor prognosis. In addition, SK-OV-3 cells with a lower expression of lncRNA GAS5 and accelerated cancer cell migration demonstrated a lower percentage of apoptosis in in vitro experiments. It was demonstrated that lncRNA GAS5 acts as a molecular sponge for miR-23a in OC cells. Additionally, WT1 was detected as a miR-23atarget genein OC cells, and through sponging miR-23a, lncRNA GAS5 positively regulated WT1 expression. Rescue tests demonstrated that enhancing the outputs of the miR-23a-WT1 axis reversed the impacts of lncRNA GAS5 silencing on cell proliferation and apoptosis in OC. The lncRNA GAS5/miR-23a/WT1 cascade was found participate in the progression of OC. lncRNA GAS5 also decreases OC progression by upregulating WT1 and attenuating miR-23a, suggesting that it could be an advantageous therapeutic target for OC intervention.

Long Non-Coding RNA GAS5 Promotes BAX Expression by Competing with microRNA-128-3p in Response to 5-Fluorouracil.

The acquisition of drug resistance is a major hurdle for effective cancer treatment. Although several efforts have been made to overcome drug resistance, the underlying mechanisms have not been fully elucidated. This study investigated the role of long non-coding RNA (lncRNA) growth arrest-specific 5 (GAS5) in drug resistance. GAS5 was found to be downregulated in colon cancer cell lines that are resistant to 5-fluorouracil (5-FU). Downregulation of GAS5 decreased the viability of HCT116 cells and the level of the pro-apoptotic BAX protein, while GAS5 overexpression promoted cell death in response to 5-FU. The interaction between GAS5 and BAX mRNA was investigated using MS2-tagged RNA affinity purification (MS2-trap) followed by RT-qPCR, and the results showed that GAS5 bound to the 3'-untranslated region of BAX mRNA and enhanced its expression by interfering with the inhibitory effect of microRNA-128-3p, a negative regulator of BAX. In addition, ectopic expression of GAS5 increased the sensitivity of resistant cells in response to anti-cancer drugs. These results suggest that GAS5 promoted cell death by interfering with miR-128-3p-mediated BAX downregulation. Therefore, GAS5 overexpression in chemo-resistant cancer cells may be a potential strategy to improve the anti-cancer efficacy of drugs.

LncRNA GAS5 regulates the Wnt/β-catenin pathway through the miR-18a-5p/AXIN2/GSK3β axis to inhibit the proliferation and migration of bladder cancer cells.

LncRNA growth arrest specific 5 (GAS5) has been confirmed to play an essential role in a number of biological processes, such as tumor regulation and gene transcription. GAS5 has been shown to be a tumor suppressor gene in many types of cancer, but its specific mechanism of action in bladder cancer (BC) remains to be elucidated. In this study, we explored the biological properties of GAS5 in BC and its mechanism of action in BC. We analyzed the expression of GAS5 in 50 pairs of BC tissues and found that GAS5 was low expressed in BC tissues compared with normal mucosal tissues. In vitro and in vivo experiments showed that GAS5 could affect the proliferation and migration of BC cells. Nucleoplasmic isolation assays and fluorescence in situ hybridization (FISH) assays demonstrated the localization of GAS5 in cell cytoplasm. Chromatin isolation by RNA purification (ChIRP), RNA immunoprecipitation (RIP) and luciferase assay demonstrated the target binding relationship of GAS5 with miR-18a-5p. Rescue experiments demonstrated that GAS5 promoted the proliferation and migration of BC cells through target binding of miR-18a-5p. Moreover, miR-18a-5p bound to its targets AXIN2 and GSK3β, which in turn affected the expression of Wnt/β-catenin pathway-related proteins. Our findings demonstrate that GAS5 regulates Wnt/β-catenin pathway activity by regulating the miR-18a-5p/AXIN2/GSK3β axis to modulate BC progression, providing a new potential therapeutic strategy for the treatment of BC.

Levels of lncRNA GAS5 in Plasma of Patients with Severe Traumatic Brain Injury: Correlation with Systemic Inflammation and Early Outcome.

Scientific efforts continue to concentrate on elucidating the complex molecular mechanisms underlying traumatic brain injury (TBI), and recent reports suggest that epigenetic regulation including long non-coding RNA (lncRNA) is involved. The present study aimed to investigate the plasma concentration of a long non-coding RNA, named growth arrest-specific 5 (GAS5), in a group of 45 patients with severe TBI (sTBI), and to analyze the correlations of GAS5 with TBI onset, injury severity, systemic inflammation, and early outcome of the patients. It was found that plasma GAS5 levels were substantially increased in sTBI patients compared with the relative controls (p < 0.001). Further, significantly higher expression of plasma GAS5 was observed in patients with a Glasgow Coma Scale (GCS) score of less than five (p = 0.002) or unfavorable outcome at discharge (p < 0.001). Circulating GAS5 expression had a negative correlation with GCS score (r = −0.406, p = 0.006), and positive correlations with white blood cell count (r = 0.473, p = 0.001), neutrophil count (r = 0.502, p < 0.001), and neutrophil/lymphocyte ratio (NLR) (r = 0.398, p = 0.007). Univariate and multivariate logistic regression analyses revealed that GCS score (OR = 0.318, 95% CI 0.132–0.767, p = 0.011) and GAS5 (OR = 2.771, 95% CI 1.025–7.494, p = 0.045) were the two independent predictors for early outcome of patients. The receiver operating characteristic (ROC) curves showed good prognostic values of GCS score (AUC = 0.856, 95% CI: 0.719–0.943) and GAS5 expression (AUC = 0.798, 95% CI: 0.651–0.903). Importantly, the combined use of them can improve the prognostic ability of TBI with an AUC of 0.895 (95% CI: 0.767–0.966). Collectively, our study indicated that the levels of lncRNA GAS5 in circulation were elevated following severe TBI and correlated well with injury severity and inflammatory parameters. In addition, GAS5 as well as GCS scores may have the potential to predict the early outcome of TBI patients.

Long non-coding RNA growth arrest specific 5 is downregulated in sepsis-ALI and inhibits apoptosis by up-regulating miR-146a

ABSTRACT Long non-coding RNA (lncRNA) growth arrest specific 5 (GAS5) and microRNA (miR)-146a both have inhibitory effects on LPS-induced inflammation, suggesting the crosstalk between them. In this study, the expression of GAS5 and miR-146a in patients with sepsis-induced acute lung injury (sepsis-ALI), sepsis patients without obvious complications (sepsis) and healthy controls were studied by RT-qPCR. The role of GAS5 in the expression and methylation of miR-146a in human bronchial epithelial cells (HBEpCs) were studied by RT-qPCR and methylation-specific PCR (MSP), respectively. Cell apoptosis was analyzed by flow cytometry. We found that GAS5 and miR-146a were downregulated in sepsis-ALI and the expression of these two were correlated. LPS induced the downregulation of GAS5 and miR-146a in HBEpCs. In HBEpCs, overexpression of GAS5 increased the expression levels of miR-146a and reduced the methylation of miR-146a gene. Under lipopolysaccharide (LPS) treatment, overexpression of GAS5 and miR-146a decreased the apoptotic rate of HBEpCs. Moreover, the combined overexpression of GAS5 and miR-146a showed stronger effects. Therefore, GAS5 is downregulated in sepsis-ALI and inhibits cell apoptosis by up-regulating the expression of miR-146a.

Influence of GAS5/MicroRNA-223-3p/P2Y12 Axis on Clopidogrel Response in Coronary Artery Disease.

BackgroundDual antiplatelet therapy based on aspirin and P2Y12 receptor antagonists such as clopidogrel is currently the primary treatment for coronary artery disease (CAD). However, a percentage of patients exhibit clopidogrel resistance, in which genetic factors play vital roles. This study aimed to investigate the roles of GAS5 (growth arrest‐specific 5) and its rs55829688 polymorphism in clopidogrel response in patients with CAD.Methods and ResultsA total of 444 patients with CAD receiving dual antiplatelet therapy from 2017 to 2018 were enrolled to evaluate the effect of GAS5 single nucleotide polymorphism rs55829688 on platelet reactivity index. Platelets from 37 patients of these patients were purified with microbeads to detect GAS5 and microRNA‐223‐3p (miR‐223‐3p) expression. Platelet‐rich plasma was isolated from another 17 healthy volunteers and 46 newly diagnosed patients with CAD to detect GAS5 and miR‐223‐3p expression. A dual‐luciferase reporter assay was performed to explore the interaction between miR‐223‐3p and GAS5 or P2Y12 3′‐UTR in (human embryonic kidney 293 cell line that expresses a mutant version of the SV40 large T antigen) HEK 293T and (megakaryoblastic cell line derived in 1983 from the bone marrow of a chronic myeloid leukemia patient with megakaryoblastic crisis) MEG‐01 cells. Loss‐of‐function and gain‐of‐function experiments were performed to reveal the regulation of GAS5 toward P2Y12 via miR‐223‐3p in MEG‐01 cells. We observed that rs55829688 CC homozygotes showed significantly decreased platelet reactivity index than TT homozygotes in CYP2C19 poor metabolizers. Platelet GAS5 expression correlated positively with both platelet reactivity index and P2Y12 mRNA expressions, whereas platelet miR‐223‐3p expression negatively correlated with platelet reactivity index. Meanwhile, a negative correlation between GAS5 and miR‐223‐3p expressions was observed in platelets. MiR‐223‐3p mimic reduced while the miR‐223‐3p inhibitor increased the expression of GAS5 and P2Y12 in MEG‐01 cells. Knockdown of GAS5 by siRNA increased miR‐223‐3p expression and decreased P2Y12 expression, which could be reversed by the miR‐223‐3p inhibitor. Meanwhile, overexpression of GAS5 reduced miR‐223‐3p expression and increased P2Y12 expression, which could be reversed by miR‐223‐3p mimic.Conclusions GAS5 rs55829688 polymorphism might affect clopidogrel response in patients with CAD with the CYP2C19 poor metabolizer genotypes, and GAS5 regulates P2Y12 expression and clopidogrel response by acting as a competitive endogenous RNA for miR‐223‐3p.

LncRNA GAS5‑mediated miR‑23a‑3p promotes inflammation and cell apoptosis by targeting TLR4 in a cell model of sepsis.

Sepsis is a syndrome characterized by organ dysfunction and an abnormal immune response to infection. A growing body of research has shown the importance of long non-coding RNAs (lncRNAs) in tumorigenesis, virus replication, inflammatory injury and other pathological processes. The aim of the present study was to explore the role and potential mechanism of the lncRNA growth arrest-specific 5 (GAS5) in the lipopolysaccharide (LPS)-induced inflammation and apoptosis of THP-1 cells. An in vitro sepsis model was established by treating THP-1 cells with LPS. Apoptosis was detected by flow cytometry. The expression levels of IL-6, IL-1β and TNF-α were detected using reverse transcription-quantitative PCR (RT-qPCR) and ELISA, and those of GAS5, microRNA (miR)-23a-3p and Toll-like receptor 4 (TLR4) were detected by RT-qPCR. The changes in the biological activity of THP-1 cells induced by the silencing of GAS5 and overexpression of miR-23a-3p and TLR4 were investigated. The relationships among GAS5, miR-23a-3p and TLR4 were analyzed using luciferase reporter assays. The results revealed that LPS increased the expression of GAS5 in THP-1 cells, and GAS5 knockdown effectively inhibited inflammation and cell apoptosis in the LPS-induced sepsis model. In addition, the results of the luciferase reporter assays indicated that both GAS5 and TLR4 directly target miR-23a-3p. The expression of miR-23a-3p was downregulated whereas that of TLR4 was upregulated in the septic cells. Further experiments showed that the overexpression of TLR4 attenuated the suppressive effects of miR-23a-3p overexpression and GAS5 knockdown on LPS-induced inflammation and apoptosis. In conclusion, the present study indicates that GAS5 strengthens LPS-induced inflammation and apoptosis via the miR-23a-3p/TLR4 pathway.

Genetic Variants of lncRNA GAS5 Are Associated with the Clinicopathologic Development of Oral Cancer

The long noncoding RNA, Growth arrest-specific 5 (GAS5) plays a crucial role in the development of oral cancer. However, potential genetic variants in GAS5 that affect the susceptibility and progression of oral cancer have rarely been explored. In this study, two loci of GAS5 single nucleotide polymorphisms (SNPs) (rs145204276 and rs55829688) were genotyped by using the TaqMan allelic discrimination in 1125 oral cancer patients and 1195 non-oral-cancer individuals. After statistical analyses, the distribution of both the GAS5 SNP rs145204276 and GAS5 SNP rs55829688 frequencies were similar between the study and control groups. However, the patients with GAS5 SNP rs145204276 variants (Ins/Del or Del/Del) showed a higher tendency of moderate to poor cell differentiation of oral cancer (OR: 1.454, 95% CI: 1.041–2.031, p = 0.028). Moreover, the GAS5 SNP rs145204276 variants (Ins/Del or Del/Del) in the non-alcohol-drinking population were associated with significantly advanced tumor stage (OR: 1.500, 95% CI: 1.081–2.081, p = 0.015) and larger tumor size (OR: 1.494, 95% CI: 1.076–2.074, p = 0.016). Furthermore, individuals with the GAS5 SNP rs145204276 variant were associated with a higher expression of GAS5 in the GTEx database (p = 0.002), and the higher GAS5 level was associated with poor cell differentiation, advanced tumor stage and larger tumor size in head and neck squamous cell carcinoma from the TCGA database (all p < 0.05). In conclusion, the GAS5 SNP rs145204276 variant is related to poor-differentiation cell status in oral cancer. Besides, the presence of the GAS5 SNP rs145204276 variant is associated with a worse tumor stage and tumor size in oral cancer patients without alcohol drinking.

Long non-coding RNA GAS5 regulates Th17/Treg imbalance in childhood pneumonia by targeting miR-217/STAT5

The imbalance of helper T (Th) 17 and regulatory T (Treg) cells plays an important role in the pathogenesis of pneumonia. This study aims to investigate the role and mechanism of long non-coding RNA growth arrest-specific 5 (GAS5) in the differentiation of Th17 cells and Tregs in childhood pneumonia. Expression of GAS5, miR-217, signal transducer and activator of transcription-5 (STAT5), receptor-related orphan receptor γt (RORγt), and transcription factor Forkhead box P3 (Foxp3) were examined by qRT-PCR and western blot. The percentage of Th17 cells and Tregs in CD4+ T cells were measured by flow cytometry. The interaction between miR-217 and GAS5 or STAT5 was analyzed by luciferase reporter assay. Downregulated GAS5 expression and Treg cell percentage, and upregulated Th17 cell percentage were observed in pneumonia patients when compared with the healthy controls. Furthermore, GAS5 overexpression corrected the imbalanced Th17/Treg in peripheral blood CD4+ T cells derived from pneumonia patients, and this effect was reversed by miR-217 mimic and STAT5 silencing. Mechanistically, GAS5 acted as a sponge of miR-217 to reduce binding of miR-217 to its target STAT5, leading to upregulation of STAT5 expression. Taken together, GAS5 corrects the Treg/Th17 imbalance by targeting the miR-217/STAT5 axis in childhood pneumonia.

Long non‑coding RNA GAS5 protects against Mycoplasmapneumoniae pneumonia by regulating the microRNA‑222‑3p/TIMP3 axis.

Mycoplasmapneumoniae pneumonia (MPP) is a type of pneumonia induced by M.pneumoniae (MP) infection. The present study investigated the effect of long non‑coding RNA growth arrest‑specific 5 (GAS5) in MPP and the underlying molecular mechanism of this. The expression of GAS5, microRNA‑222‑3p, (miR‑222‑3p) and tissue inhibitor of metalloproteinases‑3 (TIMP3) in MPP was investigated using reverse transcription‑quantitative PCR. Lipid‑associated membrane protein (LAMP)‑induced THP‑1 cells were used to model MPP. The viability of LAMP‑induced THP‑1 cells was analyzed using an MTT assay. Expression levels of interleukin (IL)‑1β, IL‑6 and tumor necrosis factor‑α (TNF‑α) pro‑inflammatory cytokines, and the anti‑inflammatory cytokine heme oxygenase‑1 (HO‑1) in LAMP‑induced THP‑1 cells were measured by ELISA. A dual‑luciferase reporter assay assessed the associations among GAS5, miR‑222‑3p and TIMP3. The expression of GAS5 and TIMP3 was downregulated in MPP. Expression of miR‑222‑3p was upregulated. GAS5‑overexpression increased the viability of LAMP‑induced THP‑1 cells. GAS5 upregulation decreased the levels of IL‑1β, IL‑6, TNF‑α and HO‑1 levels in LAMP‑induced THP‑1 cells. GAS5 directly interacted with miR‑222‑3p. TIMP3 was a target of miR‑222‑3p. miR‑222‑3p upregulation or TIMP3‑knockdown reversed the promotion effect on cell viability as well as the inhibitory effect on inflammation caused by GAS5‑overexpression in LAMP‑induced THP‑1 cells. GAS5‑overexpression increased the viability and decreased the inflammation of LAMP‑induced THP‑1 cells by regulating the miR‑222‑3p/TIMP3 axis. These results demonstrated a potential therapeutic target for MPP treatment.

Gain of GAS5 reveals worse prognosis in kidney renal clear cell carcinoma and liver hepatocellular carcinoma from the Cancer Genome Atlas dataset.

BackgroundThe role of long non-coding RNA growth arrest-specific 5 (GAS5) in cancer development is controversial. The aim of this study was to evaluate the prognostic significance of GAS5 in kidney renal clear cell carcinoma (KIRC) and liver hepatocellular carcinoma (LIHC) from The Cancer Genome Atlas (TCGA) dataset and to explore its potential regulatory mechanism through data mining.MethodsExpression of GAS5 and its clinical information within 14 kinds of cancers were obtained from TCGA dataset. The correlation between the expression of GAS5 and abhydrolase domain containing 2 (ABHD2) in KIRC and LIHC were analyzed through R2 website. The overall survival (OS) was assessed using the Kaplan-Meier method. Wilcoxon test was conducted to assess the DNA methylation of CpG sites of GAS5 or ABHD2 between normal and tumor sample in both KIRC and LIHC patients.ResultsResults showed GAS5 was significantly upregulated in KIRC and LIHC tissues compared with normal tissues, which was rarely seen in other cancers. High GAS5 expression was associated with poor overall survival (OS) in both KIRC and LIHC. Our study firstly confirmed a negative correlation between GAS5 and ABHD2 protein in both KIRC and LIHC. Methylation analysis showed that high GAS5 expression had lower DNA methylation status while low ABHD2 expression had higher DNA methylation status in both cancers.ConclusionsOur research revealed that GAS5 was likely to function as an oncogene in both KIRC and LIHC, and negatively correlated with ABHD2. Furthermore, DNA hypomethylation might have an important effect on increased GAS5 transcription and reduced ABHD2 transcription in both cancers.

Expression of two long noncoding ribonucleic acids (growth arrest-specific 5 and H19) in rheumatoid arthritis patients: Relation to clinical characteristics and disease activity

Background: Rheumatoid arthritis (RA) is a relatively common autoimmune disease in which genetic risk factors are well defined. Genetic studies are promising in exploring the long noncoding ribonucleic acids (lncRNAs): growth arrest-specific 5 (GAS5) and H19, and their possible role in the assessment of RA. Aim of the Work: The aim of the study was to describe the expression of GAS5 and H19 in serum samples of Egyptian RA patients in comparison to healthy controls, then to investigate its possible relation to RA clinical characteristics and disease activity. Patients and Methods: Levels of GAS5 and H19 expression were compared in serum samples from Egyptian RA patients (n = 100) and age- and sex-matched healthy controls (n = 100) and then correlated within the RA group to disease activity measured by the Disease Activity Score 28–erythrocyte sedimentation rate (DAS28-ESR). Results: GAS5 was downregulated (0.59 ± 0.36), while H19 was upregulated (7.41 ± 1.3) in sera of Egyptian RA patients in comparison with controls (1.07 ± 0.09 and 1.1 ± 0.09 respectively). Further analysis showed a significant negative correlation of GAS5 to DAS28-ESR (r = -0.380). However, H19 showed a positive correlation to DAS28-ESR (r = 0.487 (P Conclusion: GAS5 was related to less disease activity, while H19 tended to be associated with more active disease. They might be useful in RA as potential biomarkers for disease activity assessment in the following years. Still, further researches are needed to support our findings and precisely determine their potential utility in RA.

LncRNA GAS5 inhibits malignant progression by regulating macroautophagy and forms a negative feedback regulatory loop with the miR‑34a/mTOR/SIRT1 pathway in colorectal cancer.

Long non-coding RNA growth arrest specific 5 (GAS5) exerts inhibitory effects through the modulation of several target microRNAs (miRs) in cancer. However, its potential roles and underlying relationship during colorectal cancer (CRC) progression are unclear. Therefore, we explored the role of the negative feedback loop formed by the GAS5/miR-34a axis and mammalian target of rapamycin/sirtuin 1 (mTOR/SIRT1) pathway on macroautophagy and apoptosis in CRC. Expression of GAS5, miR-34a, SIRT1 and mTOR in CRC patients and cell lines was detected by quantitative reverse transcription polymerase chain reaction. Online bioinformatic analysis was used to predict the downstream miRs of GAS5. Luciferase assay and western blotting were performed to demonstrate miR-34a as a downstream target gene of GAS5 in CRC cells. The effects of the GAS5/miR-34a axis on apoptosis, macroautophagy, and the mTOR/SIRT1 pathway were assessed by flow cytometry, transmission electron microscopy and western blotting, respectively. Our results suggested that GAS5 was downregulated and acted as a molecular sponge of miR-34a during CRC progression. miR-34a participated in regulating GAS5-suppressed CRC cell macroautophagy and induced apoptosis through the mTOR/SIRT1 pathway. GAS5-mediated macroautophagy was maintained in an equilibrium state that might have a protective effect on CRC cell apoptosis. The mTOR signaling pathway suppressed GAS5 expression and formed a negative regulation feedback loop with miR-34a in CRC cells. Our results suggested that the GAS5/miR-34a/SIRT1/mTOR negative regulatory feedback loop mediated CRC cell macroautophagy, and maintained the cells in an autonomous equilibrium state, but not excessive activation state, which functions as a strong antiapoptotic phenotype during human CRC progression.

Modulation of the Expression of Long Non-Coding RNAs H19, GAS5, and MIAT by Endurance Exercise in the Hearts of Rats with Myocardial Infarction.

Long non-coding RNAs (lncRNAs) have a critical role in the regulation of cardiovascular function. Dysregulation of lncRNAs is implicated in the progression of cardiovascular diseases including myocardial infarction (MI). Regarding the beneficial effects of exercise (Ex) on the improvement of MI, this study aimed to investigate the effects of post-MI Ex on the expression of MI-associated lncRNAs: H19, myocardial infarction association transcript (MIAT), and growth arrest specific 5 (GAS5). MI was induced by left anterior descending (LAD) coronary artery ligation in male Wistar rats. One week later, rats were exercised under a moderate-intensity protocol for 4weeks. In the end, hemodynamic parameters and cardiac function indices were measured. Assessment of fibrotic areas and apoptosis was performed by Masson's trichrome staining and immunohistochemistry, respectively. Expression of genes was evaluated by real-time PCR. Ex significantly reduced the fibrotic areas (P < 0.05) and apoptosis and increased contractility indices (P < 0.01), and cardiac function (P < 0.05) in MI groups. The reduced expression of H19 (P < 0.01) in MI rats returned to normal levels by Ex. Ex significantly (P < 0.001) reduced the expression of MIAT and increased the expression of GAS5 (P < 0.01), which had changed in the hearts of rats with MI. The present study indicated the beneficial effect of Ex on the improvement of cardiac function and reduction of fibrosis in infarcted heart possibly through regulation of the expression of lncRNAs: H19, GAS5, and MIAT.

Circulating long noncoding RNA, GAS5, as a novel biomarker for patients with atrial fibrillation.

BackgroundCirculating long noncoding RNA (lncRNA) plays a vital role in clinical disease diagnosis and prognosis. Here, we evaluate the role of a lncRNA, named growth arrest specific 5 (GAS5), in atrial fibrillation (AF).MethodsExpression of GAS5 was measured by qRT‐PCR. Diagnostic and prognostic values of GAS5 were assessed by the receiver operating characteristics curve (ROC), Kaplan–Meier (KM) and Cox regression analyses.ResultsA total of 173 participants were enrolled in this study. Circulating GAS5 expression was significantly down‐regulated in AF patients. This change occurred prior to enlargement of the left atrial volume and was strongly associated with AF progression, which demonstrates the potential use of GAS5 as an early biomarker. The area under the ROC curve (AUC) was 0.858 (95% CI 0.789‐0.926, P < .001). Seventy of the 85 AF patients received radiofrequency catheter ablation (RFCA), and 22 (31.4%) had relapsed by the 1‐year follow‐up. The KM analysis (log‐rank test, P = .031) and multivariable Cox analysis (HR = 0.127, 95% CI 0.026‐0.616; P = .01) revealed that GAS5 has a role in predicting recurrence after RFCA.ConclusionCirculating lncRNA GAS5 is a potential biomarker for AF diagnosis and prognosis. Down‐regulation of GAS5 occurs prior to left atrial enlargement and can be used for the prognosis of AF progression and recurrence.

Impact of Gene Polymorphisms in GAS5 on Urothelial Cell Carcinoma Development and Clinical Characteristics.

Urothelial cell carcinoma (UCC) is the commonest malignant tumor of the urinary tract and the second most common kidney cancer malignancy. Growth arrest-specific 5 (GAS5), a long noncoding RNA, is encoded by the GAS5 gene and plays a critical role in cellular growth arrest and apoptosis. In the current study, two single nucleotide polymorphisms (SNPs) in the GAS5 gene, rs145204276 and rs55829688, were selected to investigate correlations between these single SNPs and susceptibility to UCC. A total of 430 UCC cases and 860 ethnically matched healthy controls were included. SNP rs145204276 and SNP rs55829688 were determined using a TaqMan genotyping assay. Logistic regression models demonstrated that female patients with UCC carrying the rs145204276 GAS5 Ins/Del or Del/Del genotype had a 3.037-fold higher risk of larger tumor status (95% confidence interval 1.259–7.324) than did rs145204276 wild type (Ins/Ins) carriers (p = 0.011). The Cancer Genome Atlas validation cohort analysis demonstrated that the expression of GAS5 in female patients with bladder urothelial carcinoma (BLCA) with larger tumor size was much lower than that in patients with a smaller tumor size (p = 0.041). Kaplan-Meier curve analysis and the log–rank test revealed that female patients with BLCA and lower GAS5 expression had poorer overall survival than those with higher GAS5 expression. In conclusion, genetic variations in GAS5 rs145204276 may serve as a critical predictor of the clinical status of female patients with UCC.

Long Non-coding RNA Gas5 Is Associated With Preeclampsia and Regulates Biological Behaviors of Trophoblast via MicroRNA-21.

Preeclampsia is a lethal pregnancy specific hypertensive disorder involving multisystem. Despite extensive studies to investigate the causes of preeclampsia, the pathogenesis still remains largely unknown. Long non-coding RNAs (lncRNAs) are a diverse class of non-translated RNAs which play a crucial part in various biological phenomena. Although lncRNA Growth Arrest-Specific 5 (GAS5) aberrantly expressed in multiple cancer tissues and is implicated in multiple biological processes of tumor cells, little is known about its role in preeclampsia. In this study, 40 patients with preeclampsia and 32 gestational age matched normotension pregnant women were recruited. Using quantitative real-time polymerase chain reaction (qRT-PCR), we found higher expression of GAS5 in placenta of preclamsia affected women. The level of GAS5 existed strongly in correlation with Thrombin Time indicating coagulation function and other clinical parameters by Pearson correlation analysis. Then we constructed the GAS5 lentivirus expression vectors and transfected into human trophoblast cell lines HTR-8/SVneo and JEG-3. Using in vitro cell culture studies, we found an inhibited effect of GAS5 on proliferative ability, migratory ability and invasive ability however; no effect on apoptosis was detected. Further mechanistic analysis found that GAS5 modulated microRNA-21 (miR-21) in an opposite variation tendency by qRT-PCR and rescue experiment. In addition, inhibition of GAS5 promoted the activation of PI3K/AKT signaling pathway and its downstream proteins covering MMP-9 and TP53 as evident from our qRT-PCR and western blot analyses. Thus, we suggested that GAS5 might involve in pregnancy with preeclampsia by influencing the biological functions of trophoblast cells through the regulation of miR-21 and activation of PI3K/AKT signaling pathway and its downstream targets, which may contribute to reveal the nature of preeclampsia.

Long non‑coding RNA GAS5 regulates myocardial ischemia‑reperfusion injury through the PI3K/AKT apoptosis pathway by sponging miR‑532‑5p.

Long non-coding RNAs (lncRNAs) have been revealed to have a marked effect in cardiovascular diseases, including during cardiac development, cardiac hypertrophy, myocardial fibrosis and myocardial ischemic injury. The mechanism of myocardial ischemia-reperfusion injury (MIRI) is very complicated. Although studies have confirmed that lncRNAs are involved, the specific mechanism remains largely unknown. The lncRNA growth arrest specific 5 (GAS5) is known as a regulator of a number of diseases, including certain cancer types. The present study aimed to investigate the function of lncRNA GAS5 in MIRI. The present study reported that the expression of lncRNA GAS5 in H9c2 cells treated with anoxia and reoxygenation was significantly upregulated compared with the control group (P<0.05). Similarly, the expression of lncRNA GAS5 in myocardial tissue obtained from rats treated with MIRI was significantly upregulated compared with the untreated controls (P<0.05). Silencing of lncRNA GAS5 was able to attenuate myocardial damage, as cell viability increased and the apoptosis rate decreased. Classical apoptotic proteins involved in MIRI, including B-cell lymphoma 2, Bcl-2-associated X protein and cleaved caspase-3, also exhibited the same trend. At the same time, when lncRNA GAS5 was silenced, microRNA (miR)-532-5p, which was originally expressed at the stage of injury, was upregulated. The luciferase reporter assay results indicated that the lncRNA GAS5 functioned as a molecular sponge of miR-532-5p. The gain- and loss-of-function analysis of miR-532-5p indicated that it was involved in the regulation of MIRI; the trend of results following its overexpression was also consistent with the trend observed following the silencing of lncRNA GAS5. Notably, the protective effect of lncRNA GAS5 silencing on cells was attenuated by miR-532-5p inhibition. Phosphatase and tensin homolog was revealed to be a key target gene for the function of lncRNA GAS5, and its regulation was achieved via binding to miR-532-5p. In other words, silencing lncRNA GAS5 ultimately promoted the activation of the phosphoinositide-3-kinase (PI3K)/protein kinase B pathway (AKT) to reduce myocardial damage. Therefore, lncRNA GAS5 was able to regulate MIRI through the PI3K/AKT apoptosis pathway by sponging miR-532-5p.