Levels Of Growth Arrest-specific Transcript 5 Research Articles

Expression profiles of the lncRNA antisense GAS5-AS1 in colon biopsies from pediatric inflammatory bowel disease patients and its role in regulating sense transcript GAS5.

The long non-coding RNA (lncRNA) growth arrest-specific transcript 5 (GAS5) level was demonstrated as involved in pediatric inflammatory bowel disease (IBD) pathogenesis. Since its antisense transcript GAS5-AS1 has never been investigated in IBD, this study aims to detect whether GAS5-AS1 and GAS5 levels are related to IBD clinical parameters and investigate their correlation in vitro. Twenty-six IBD pediatric patients were enrolled; paired inflamed and non-inflamed intestinal biopsies were collected. We evaluated GAS5 and GAS5-AS1 levels by real-time PCR. The role of GAS5 and GAS5-AS1 was assessed in vitro by transient silencing in THP1-derived macrophages. GAS5-AS1 and GAS5 levels were associated with patients' clinical parameters; GAS5-AS1 expression was downregulated in inflamed tissues and inversely correlated with disease activity. A positive correlation between GAS5-AS1 and GAS5 levels was observed in non-inflamed biopsies. On THP1-derived macrophages, a reduced amount of both GAS5-AS1 and GAS5 was observed; accordingly, matrix metalloproteinase (MMP) 9 was increased. After GAS5-AS1 silencing, a downregulation of GAS5 was found, whereas no effect was detected on GAS5-AS1 after GAS5 silencing. Conclusion: This study provided for the first time new insights into the potential role of GAS5-AS1 in IBD. GAS5-AS1 modulates GAS5 levels in vitro and may serve as a potential IBD diagnostic biomarker. What is Known: • GAS5 is involved in regulating intestinal MMP-2 and MMP-9 in pediatric patients with IBD; • GAS5-AS1 has never been investigated in the context of IBD; • GAS5-AS1 regulates the expression of GAS5, increasing its stability in tissues and in vitro cell models of cancer. What is New: • GAS5-AS1 correlated with GAS5 and IBD clinical parameters; • GAS5-AS1 can modulate GAS5 levels in macrophages; • GAS5-AS1 may serve as potential IBD diagnostic biomarker.

LncRNA GAS5 regulated by FTO-mediated m6A demethylation promotes autophagic cell death in NSCLC by targeting UPF1/BRD4 axis.

Long non-coding RNA (lncRNA) growth arrest-specific transcript 5 (GAS5) has been shown to be a regulator for many cancers, including non-small cell lung cancer (NSCLC). Therefore, its role and mechanism in the process of NSCLC deserve to be further revealed. The expression levels of GAS5, fat mass and obesity-associated protein (FTO) and bromodomain-containing protein 4 (BRD4) were detected by quantitative real-time PCR. Western blot analysis was used to examine the protein expression of FTO, BRD4, up-frameshift protein 1 (UPF1) and autophagy-related markers. Methylated RNA immunoprecipitation was used to assess the m6A level of GAS5 regulated by FTO. Cell proliferation and apoptosis were determined using MTT assay, EdU assay and flow cytometry. Autophagy ability was assessed by immunofluorescence staining and transmission electron microscope. Xenograft tumor model was constructed to explore the effects of FTO and GAS5 on NSCLC tumor growth in vivo. The interaction between UPF1 and GAS5 or BRD4 was confirmed by pull-down assay, RIP assay, dual-luciferase reporter assay, and chromatin immunoprecipitation. Fluorescent in situ hybridization was used to analyze the co-localization of GAS5 and UPF1. Actinomycin D treatment was employed to evaluate BRD4 mRNA stability. GAS5 was downregulated in NSCLC tissues and was associated with poor prognosis in NSCLC patients. FTO was highly expressed in NSCLC, and it inhibited GAS5 expression by reducing GAS5 m6A methylation level. GAS5 suppressed by FTO could promote the autophagic death of NSCLC cells in vitro and inhibit NSCLC tumor growth in vivo. In addition, GAS5 was able to interact with UPF1 to reduce the mRNA stability of BRD4. Knockdown of BRD4 reversed the inhibition of GAS5 or UPF1 silencing on the autophagic cell death of NSCLC. The findings of the study showed that lncRNA GAS5 mediated by FTO could contribute to the autophagic cell death of NSCLC by interacting with UPF1 to reduce BRD4 mRNA stability, suggesting that GAS5 might be a vital therapy target for NSCLC progression.

GAS5 alleviates cisplatin drug resistance in oral squamous cell carcinoma by sponging miR-196a.

The long non-coding RNA Growth-arrest-specific transcript 5 (GAS5) has been extensively linked with the ability of cancer cells to resist chemotherapeutic interventions. This prospective study aimed to investigate the role of GAS5 in oral squamous cell carcinoma (OSCC), which has been poorly characterized to date. GAS5 and miR-196a expression levels were detected by quantitative real-time PCR analysis. Cisplatin (DDP) sensitivity and apoptosis levels were determined using Cell Counting Kit 8 and flow cytometry, respectively. Luciferase reporter and RNA immunoprecipitation assays were performed to confirm target miRNAs of GAS5. We found that GAS5 was expressed at low levels in DDP-resistant OSCC cell lines and tissues, and that GAS5 levels were intricately linked to the survival rates of OSCC patients. GAS5 overexpression led to the recovery of DDP sensitivity in CAL27/DDP cells. Additionally, in both DDP-resistant and -sensitive lines, GAS5 showed a cytoplasmic distribution and downregulated miR-196a in OSCC tissues. Exogenous transfection of miR-196a alleviated the effects of GAS5 on DDP sensitivity, confirming this as the mechanism of chemoresistance. These findings may provide new targets for the treatment of chemotherapy-resistant OSCC.

Level of LncRNA GAS5 and Hippocampal Volume are Associated with the Progression of Alzheimer's Disease.

PurposeWe evaluated the diagnostic value of long non-coding RNA growth arrest-specific transcript 5 (GAS5) and its relationship with hippocampal volume in Alzheimer’s disease (AD).Patients and MethodsOne hundred and eight patients with AD and 83 healthy controls were included, and demographic data, biochemical parameters, GAS5 levels, and hippocampal volume were recorded. Chi-squared tests or independent sample t-tests were used to compare the baseline characteristics, relative expression of GAS5, and hippocampal volume. Correlations between variables were determined using Spearman’s rank correlation test. Receiver operating characteristic (ROC) curves were generated to compare the diagnostic value of GAS5 and total hippocampal volume in AD.ResultsThe levels of GAS5 were significantly upregulated in patients with AD compared with those in controls and were negatively correlated with MMSE score. There were differences in left hippocampal volume, right hippocampal volume, and total hippocampal volume between the two groups. Total hippocampal volume was positively correlated with MMSE score and negatively correlated with GAS5 expression in patients with AD. The area under the curve (AUC) of for GAS5 expression was 0.831, the sensitivity was 61.1%, and the specificity was 95.2%. The AUC of the combined total hippocampal volume was 0.891, the sensitivity was 74.1%, and the specificity was 92.8%.ConclusionThe results suggested that GAS5 may be an excellent indicator of AD progression alone or in combination with hippocampal volume.

LncRNA GAS5 suppresses ovarian cancer progression by targeting the miR-96-5p/PTEN axis.

BackgroundLong non-coding RNAs (lncRNAs) play critical roles in the occurrence and progression of various tumors, including ovarian cancer (OC). The lncRNA growth arrest-specific transcript 5 (GAS5) has been shown to be an important modulator in the growth and metastasis of OC cells. Our previous studies confirmed that GAS5 was down-regulated in OC; however, the potential underlying molecular mechanism underlying has not yet been elucidated.MethodsWe screened the Gene Expression Profiling Interactive Analysis (GEPIA) database for the expression of the lncRNA GAS5 in OC. Cell Counting Kit-8 (CCK-8), transwell assay, colony formation assay, flow cytometry analysis, and western blotting were applied to determine the various functions of GAS5 in OC progression. The competing endogenous RNA (ceRNA) mechanism was verified through bioinformatics analysis, dual-spectral luciferase reporter gene assay, and RNA immunoprecipitation assay (RIPA). Finally, the expression interactions between microRNA-96-5p, phosphatase and tensin homolog deleted on chromosome ten (PTEN), and GAS5 were measured.ResultsOur results demonstrated decreased expression levels of GAS5 and PTEN in OC samples and cell lines, while miR-96-5p was up-regulated when compared with the controls. GAS5 overexpression could significantly reduce OC cell proliferation and invasion ability via suppression of miR-96-5p expression. Moreover, GAS5 could influence the PTEN/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling pathway.ConclusionsOur study identified GAS5 as a ceRNA that can regulate the PTEN/AKT/mTOR axis by sponging miR-96-5p in OC.

GAS5 regulates diabetic cardiomyopathy via miR‑221‑3p/p27 axis‑associated autophagy

Diabetic cardiomyopathy (DCM) is one of the primary complications of the cardiovascular system due to diabetes-induced metabolic injury. The present study investigated the autophagy-associated regulatory mechanisms of long non-coding RNAs in cardiac pathological changes in diabetes mellitus (DM). Streptozotocin (STZ)-induced diabetic rats were intramyocardially injected and high concentration glucose (HG)-processed H9C2 cells were infected with growth arrest specific transcript 5 (GAS5)-loaded AAV-9 adenovirus. HG-processed H9C2 cells also underwent transfection with small interfering RNA-p27. Hematoxylin and eosin and Masson staining evaluated myocardial histological changes. Quantitative PCR detected the expression levels of GAS5, fibrosis markers (collagen I, collagen III, TGF-β and connective tissue growth factor) and microRNA (miR)-221-3p. Western blotting determined the expression levels of autophagy-associated proteins [microtubule-associated proteins 1A/1B light chain 3B (LC3B) I, LC3B II and p62] and p27. Targetscan7.2 was used to predict binding sites between miR-221-3 and p27. Dual luciferase reporter assayed the effect of miR-221-3p on luciferase activity of GAS5 and p27. GAS5 downregulated high blood glucose concentrations in STZ-induced diabetic rats, however its expression levels decreased in both HG-processed H9C2 cells and the myocardium of DM model rats. GAS5 attenuated the histological abnormalities and reversed the decreased LC3B II and increased p62 expression levels of DM model rats. miR-221-3p mimic suppressed the activity of both GAS5-wild-type (WT) and p27-WT. miR-221-3p expression levels were increased in both HG-processed H9C2 and diabetic myocardium. p27 expression levels decreased following HG but were upregulated by GAS5. sip27 abolished the effect of GAS5 on DCM. GAS5 promoted cardiomyocyte autophagy in DCM to attenuate myocardial injury via the miR-221-3p/p27 axis.

RETRACTED: Long non-coding RNA GAS5 retards neural functional recovery in cerebral ischemic stroke through modulation of the microRNA-455-5p/PTEN axis

Cerebral ischemic stroke (IS) threatens the daily life of individuals, with high mortality. Emerging studies have deciphered the independent roles of the long non-coding RNA growth-arrest-specific transcript 5 (GAS5), microRNA (miR)-455-5p and phosphatase and tensin homolog (PTEN) in IS, but the understanding of their integrated function is in its infancy. Therefore, this study focusing on the GAS5/miR-455-5p/PTEN axis was initiated. Middle cerebral artery occlusion (MCAO) models were established by the suture method. GAS5, miR-455-5p and PTEN expression was detected in rat brain tissues after MCAO. Rats were injected with sh-GAS5 or miR-455-5p agomir before MCAO modeling. A neurobehavioral evaluation was conducted, and oxidative stress injury, apoptosis and mitochondrial function were detected in brain tissues of IS rats. The relationships between GAS5 and miR-455-5p, and between miR-455-5p and PTEN were verified. PC12 cells were transfected with sh-GAS5 or miR-455-5p mimic under oxygen and glucose deprivation/reoxygenation (OGD/R) conditions to evaluate cell viability and apoptosis. GAS5 and PTEN expression levels were elevated and miR-455-5p expression was reduced in brain tissues of MCAO rats and OGD/R-induced PC12 cells. GAS5 downregulation or miR-455-5p upregulation improved neurobehavior, attenuated apoptosis and oxidative injury, and relieved mitochondrial damage in brain tissues of IS rats. Silencing GAS5 or restoring miR-455-5p minimized OGD/R-induced cell damage. MiR-455-5p downregulation antagonized the effects of GAS5 inhibition on IS. This work elucidates that GAS5 downregulation upregulates miR-455-5p to repress PTEN expression, in turn attenuating IS, which may broaden the horizon of IS treatment.

<p>lncRNA GAS5 Is Upregulated in Osteoporosis and Downregulates miR-21 to Promote Apoptosis of Osteoclasts</p>

BackgroundIt has been reported that lncRNA growth arrest-specific transcript 5 (GAS5) interacts with miR-21, which plays critical roles in osteoporosis. The involvement of GAS5 in osteoporosis was investigated in this study.MethodsExpression levels of GAS5 and miR-21 in plasma of both osteoporosis patients and healthy controls were determined by RT-qPCR. Diagnostic values of GAS5 and miR-21 for osteoporosis were analyzed by ROC curve analysis. Overexpression experiments were used to assess the interactions between GAS5 and miR-21. The roles of GAS5 and miR-21 in the apoptosis of osteoclasts were investigated by cell apoptosis assay.ResultsThe present study aimed to investigate the roles of GAS5 in osteoporosis. The results showed that GAS5 was upregulated, while miR-21 was downregulated in plasma of osteoporosis patients. Expression levels of GAS5 and miR-21 were inversely correlated across plasma samples from osteoporosis patients but not the plasma samples from the controls. Altered expression of GAS5 and miR-21 distinguished osteoporosis patients from the controls. In osteoclasts, overexpression of GAS5 led to downregulation of miR-21, while overexpression of miR-21 did not affect the expression of GAS5. Overexpression of GAS5 led to promoted apoptosis of osteoclasts, while overexpression of miR-21 led to suppressed apoptosis of osteoclasts. In addition, overexpression of miR-21 attenuated the enhancing effects of overexpressing GAS5 on cell apoptosis.ConclusionGAS5 is upregulated in osteoporosis and may downregulate miR-21 to promote the apoptosis of osteoclasts.

Expression of the Long Noncoding RNA GAS5 Correlates with Liver Fibrosis in Patients with Nonalcoholic Fatty Liver Disease

Background: Advanced liver fibrosis is the most important prognostic factor in nonalcoholic fatty liver disease (NAFLD). The long noncoding RNA (lncRNA), growth arrest-specific transcript 5 (GAS5), is associated with the inhibition of liver fibrogenesis, and its levels are decreased in cirrhotic liver. Methods: We analyzed 51 patients with NAFLD, the diagnosis of which was confirmed by liver biopsy. Expression of GAS5 in both the liver and plasma of the patients was analyzed using a quantitative real-time polymerase chain reaction according to the fibrosis stage. Results: Plasma GAS5 expression was significantly higher in patients with advanced fibrosis than in those without. As the fibrosis progressed, GAS5 expression in plasma increased, with the exception of that in cirrhotic livers. Plasma levels of GAS5 were lower in patients with cirrhosis than in those with advanced fibrosis. Conclusion: Elevated circulating levels of the lncRNA GAS5 are associated with the progression of liver fibrosis prior to the development of cirrhosis.

LncRNA growth arrest-specific transcript 5 targets miR-21 gene and regulates bladder cancer cell proliferation and apoptosis through PTEN.

The aim of this study was to investigate the mechanism by which growth arrest‐specific transcript 5 (GAS5) regulates bladder cancer cells. Bladder cancer samples were collected and tested for experiment. Dual‐luciferase reporter assay was used to verify the downstream target genes for GAS5 and miR‐21. The expression level of GAS5 was decreased and that of miR‐21 was increased, indicating a negative correlation between the two. Patients with high GAS5 level and low miR‐21 level had relatively longer survival rates. GAS5 inhibited bladder cancer cells proliferation and promoted apoptosis, and miR‐21 had the opposite effects. MiR‐21 was a direct target for GAS5, whereas phosphatase and tensin homolog (PTEN) was a direct target gene of miR‐21. Low expression of miR‐21 could reverse the proliferative and antiapoptotic effects caused by GAS5 silencing. High levels of GAS5 and low levels of miR‐21 might be associated with a higher survival rate in bladder cancer patients. GAS5 could exert antiproliferative and proapoptotic effects on bladder cancer cells through miR‐21 and PTEN.

LncRNAs as New Biomarkers in Systemic Lupus Erythematosus: A Prospective Study

Aim: To investigate serum levels of two Immune-related functional lncRNAs, growth arrest-specific transcript 5 (GAS5) and metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), in Egyptian patients with SLE and to evaluate their relationship with disease activity. Method : The present study was a case-control study that was carried out on 39 patients with SLE and 46 age and sex-matched healthy controls. The expression levels of GAS5 and MALAT1 were measured using by real-time polymerase chain reaction (PCR). Results : There were statistically significant differences between cases and controls in GAS5 (p <0.001) and MALAT1 expression (p <0.01). The mean GAS5 was significantly higher in the control; while the mean MALATI expression was significantly higher in SLE patients. The ROC curve revealed that GAS5 was a good discriminant with AUC 0.849 with sensitivity 93.5% and specificity 74.3%. Moreover, MALAT1 was a good discriminant to differentiate cases from controls with AUC 0.3 with 95% CI (0.162 - 0.438), the most suitable cut-off point was ≥ 2.1 with Sensitivity 93.5% and Specificity 72.5%. Conclusion : GAS5 and MALAT1 may serve as potential biomarkers for the diagnosis and monitoring of the SLE, both lnRNAs exhibited a good diagnostic accuracy to discriminate between SLE patients and healthy controls.

Long non-coding RNA GAS5 promotes osteogenic differentiation of bone marrow mesenchymal stem cells by regulating the miR-135a-5p/FOXO1 pathway

Studies have shown that promoting the differentiation of bone marrow mesenchymal stem cells (BMSCs) into osteoblasts could protect against osteoporosis. Increasing evidence demonstrates that long non-coding RNAs (lncRNAs) participate in BMSC osteogenic differentiation. This study aimed to investigate the role and underlying mechanism of growth arrest-specific transcript 5 (GAS5) in osteogenic differentiation. The mechanism was mainly focused on miR-135a-5p/FOXO1 pathway by gain- and loss-of function tests. GAS5 and FOXO1 expression was decreased, whereas miR-135a-5p expression was increased, in the BMSCs from osteoporotic mice. Levels of GAS5 and FOXO1 were increased and miR-135a-5p expression was decreased during osteogenic differentiation of BMSCs. Overexpression of GAS5 promoted, whereas knockdown of GAS5 suppressed, BMSC osteogenic differentiation. As for the mechanism, GAS5 functioned as a competing endogenous RNA for miR-135a-5p to regulate FOXO1 expression. In conclusion, GAS5 promoted osteogenesis of BMSCs by regulating the miR-135a-5p/FOXO1 axis. This finding suggests that targeting GAS5 may be a useful therapy for treating postmenopausal osteoporosis.

LncRNA GAS5 overexpression downregulates IL-18 and induces the apoptosis of fibroblast-like synoviocytes.

Long non-coding RNA (lncRNA) growth arrest specific transcript 5 (GAS5) negatively regulates interleukin-18 (IL-18) in ovarian cancer, while IL-18 contributes to the development of rheumatoid arthritis (RA). Therefore, GAS5 may also participate in RA. GAS5 and IL-18 in plasma of RA patients (n = 60) and healthy controls (n = 60) were measured by RT-qPCR and ELISA, respectively. Linear regression was performed to analyze the correlations between plasma levels of IL-18 and GAS5 in both RA patients and healthy controls. In the present study, we found that plasma GAS5 was downregulated, while IL-18 was upregulated in RA patients than in healthy controls. A significant and inverse correlation between GAS5 and IL-18 was found in RA patients but not in healthy controls. IL-18 treatment did not significantly alter the expression of GAS5 in fibroblast-like synoviocytes, while GAS5 overexpression led to the inhibited expression of IL-18. GAS5 overexpression also resulted in the promoted apoptosis of fibroblast-like synoviocytes. Therefore, GAS5 overexpression may improve RA by downregulating IL-18 and inducing the apoptosis of fibroblast-like synoviocytes. Key points • The present study mainly showed that overexpression of GAS5 may assist the treatment of RA. • The mechanism of GAS5 for the treatment of RA involves the downregulating inflammatory IL-18 and mediating the apoptosis of fibroblast-like synoviocytes. • GAS5 and IL-8 were correlated in RA patients but not in healthy controls.

GAS5 promotes podocyte injury in sepsis by inhibiting PTEN expression.

To investigate the potential role of long noncoding RNA (lncRNA) growth arrest specific transcript 5 (GAS5) in sepsis-induced podocyte injury and its underlying mechanism. The sepsis model was established by lipopolysaccharide (LPS) induction in podocytes. The expression levels of Nephrin and GAS5 were detected by quantitative Real-time polymerase chain reaction (qRT-PCR) after LPS induction in podocytes for 12 h, 24 h and 36 h, respectively. Western blot was used to detect the expression level of Nephrin in sepsis-induced podocytes. The mRNA expressions of GAS5 and Nephrin in podocytes were detected after transfection of GAS5 siRNA. Albumin influx in podocytes after GAS5 knockdown was detected by Transwell assay. Western blot was used to detect the protein expression of Snail in sepsis after GAS5 knockdown. The target gene of GAS5 was predicted by bioinformatics analysis. QRT-PCR and Western blot were used to detect the protein and mRNA levels of PTEN (phosphatase and tensin homolog deleted on chromosome ten). Nephrin expression and the albumin inflow after PTEN knockdown were then measured. The expression of PI3K/AKT/GSK3β was also detected after GAS5 was downregulated while PTEN was upregulated. LPS stimulation downregulated the mRNA expression of Nephrin in podocytes and achieved the lowest level at 24 h. The protein expression change of Nephrin was consistent with its mRNA expression. In the septic state, the albumin influx of podocytes remarkably increased, but the function of podocyte barrier was weakened. Besides, GAS5 expression decreased in a time-dependent manner in LPS-induced podocytes. After GAS5 knockdown by siRNA, Nephrin expression and the function of podocyte barrier were significantly reduced. Snail expression was also upregulated in septic state, and GAS5 knockdown increased the expressions of phosphorylated Snail and PI3K/AKT/GSK3β. After knockdown of GAS5, the mRNA and protein levels of PTEN significantly decreased, which was contract to the expression of Snail. However, overexpression of PTEN could reverse the promotive effect of GAS5 on PI3K/AKT activation. GAS5 expression decreased in sepsis-induced podocyte injury, and GAS5 was involved in regulating sepsis-induced podocyte injury by reducing PTEN expression.

Knockdown of growth-arrest specific transcript 5 restores oxidized low-density lipoprotein-induced impaired autophagy flux via upregulating miR-26a in human endothelial cells

Endothelial cells injury and autophagy dysfunction play vital roles in the development of atherosclerosis. Long noncoding RNAs (lncRNAs) have been identified to participate in the pathogenesis of atherosclerosis. However, it remains largely undefined whether lncRNA growth-arrest specific transcript 5 (GAS5) could influence ox-LDL-induced autophagy dysfunction in endothelial cells. The expression levels of GAS5 and miR-26a were detected in the plasma samples of patients with atherosclerosis and oxidized low-density lipoprotein (ox-LDL)-treated human aortic endothelial cells (HAECs) by quantitative real-time PCR (qRT-PCR). Luciferase reporter assay, RNA immunoprecipitation (RIP), and RNA pull down were performed to validate whether GAS5 could directly interact with miR-26a. The effects of ox-LDL, GAS5 or combined with miR-26a on apoptosis and autophagy were evaluated by flow cytometry analysis and western blot, respectively. Results showed that GAS5 expression was upregulated and miR-26a was downregulated in the plasma samples of patients with atherosclerosis and ox-LDL-treated HAECs. There was an interaction of reciprocal inhibition between GAS5 and miR-26a expressions in ox-LDL-treated HAECs. We further demonstrated that GAS5 directly bound to miR-26a in HAECs. Additionally, ox-LDL administration induced apoptosis and impaired autophagy flux in HAECs. Moreover, GAS5 knockdown inhibited cell apoptosis and activated autophagy flux, whereas inhibition of miR-26a reversed the effect of GAS5 in HAECs. These results revealed a novel regulatory mechanism for ox-LDL-induced impaired autophagy flux in endothelial cells.

LncRNA GAS5 inhibits colorectal cancer cell proliferation via the miR‑182‑5p/FOXO3a axis.

Long non‑coding RNAs(lncRNAs) are mainly involved in diverse biological processes in human malignancies. The expression profile and underlying mechanism of the lncRNA growth arrest specific transcript5(GAS5) in colorectal cancer(CRC) are poorly understood. Here, we investigated the role of GAS5 in human CRC tissues. lncRNA GAS5 was specifically downregulated in CRC tissues and cell lines. Reduced GAS5 levels were significantly associated with advanced clinical stage and lymph node metastasis in CRC. GAS5 overexpression suppressed CRC cell proliferation and promoted cellular apoptosis. A dual‑luciferase reporter assay showed that GAS5 could negatively regulate the expression of microRNA(miR)‑182‑5p. Upregulated miR‑182‑5p abrogated the effect of GAS5 overexpression on CRC cell proliferation and apoptosis. Furthermore, GAS5 positively regulated the expression of FOXO3a in CRC cells. Taken together, these findings suggest that overexpression of the lncRNA GAS5 inhibits cell proliferation and promotes apoptosis by inhibiting miR‑182‑5p expression, and thus could be a therapeutic target in CRC.

Long non-coding RNA GAS5 inhibits ovarian cancer cell proliferation via the control of microRNA-21 and SPRY2 expression.

In recent decades, numerous long non-coding (lnc)RNAs, including growth arrest-specific transcript 5 (GAS5), have been demonstrated to exert promoting or suppressive effects in human cancers. Decreased expression of the lncRNA GAS5 was reported to promote cell proliferation, migration and invasion and indicate poor prognosis in ovarian cancer. However, the exact underlying molecular mechanism through which GAS5 is involved in ovarian cancer growth remains unknown. The present study aimed to investigate the regulatory mechanism of GAS5 in ovarian cancer cell proliferation. Quantitative polymerase chain reaction and western blot analysis were used to examine RNA and protein expression, respectively. An MTT assay was used to examine cell proliferation. A luciferase reporter gene assay was conducted to verify the targeting relationship. It was identified that the expression levels of GAS5 and Sprouty homolog 2 (SPRY2) were significantly downregulated, while the expression level of microRNA (miR)-21 was significantly upregulated in ovarian cancer tissues and cell lines compared with adjacent non-tumor tissues and normal ovarian epithelial cells, respectively. Downregulation of GAS5 was significantly associated with advanced clinical stage. Luciferase assay data indicated that miR-21 was a direct target of GAS5 and that SPRY2 was a target gene of miR-21 in ovarian cancer-derived A2780 cells. GAS5 overexpression significantly inhibited the proliferation of ovarian cancer cells, which was accompanied by the downregulation of miR-21 and the upregulation of SPRY2. The overexpression of miR-21 caused a significant decrease in A2780 cell proliferation, which was accompanied by reduced SPRY2 expression. Furthermore, miR-21 overexpression attenuated the suppressive effects of GAS5 on A2780 cell proliferation and rescued the promoting effects of GAS5 on SPRY2 expression. In addition, the knockdown of SPRY2 also rescued the suppressive effects of GAS5 on the proliferation of A2780 cells. In summary, our study demonstrates that GAS5 exerts a suppressive effect on the proliferation of ovarian cancer cells, at least in part via the inhibition of miR-21 expression and subsequent increased SPRY2 expression. These findings suggest that the GAS5/miR-21/SPRY2 signaling pathway may be a potential therapeutic target in ovarian cancer.

The Growth Arrest-Specific Transcript 5 (GAS5) and Nuclear Receptor Subfamily 3 Group C Member1 (NR3C1): Novel Markers Involved in Multiple Sclerosis.

Recent studies have revealed that long noncoding RNAs (lncRNAs) are connected with pathogenesis of neurodegenerative diseases. Additionally, glucocorticoids have fundamental regulatory roles on the immune system, and act as potent therapeutic compounds for autoimmune and inflammatory diseases. The long noncoding RNA growth arrest-specific 5 (GAS5) which accumulates inside the cells in response to cellular starvation/growth arrest, acts as a potent repressor of the glucocorticoid receptor (GR) through its glucocorticoid response element (GRE). The aim of the present study was to investigate the role of lncRNA GAS5 and its downstream target Nuclear Receptor Subfamily 3 Group C Member 1(NR3C1) in the pathogenesis of multiple sclerosis (MS), and to define the role of GAS5 in the regulation of NR3C1 expression. Quantitative polymerase chain reaction was performed for investigating the expression of GAS5 and NR3C1 in MS patients and healthy subjects. We found that GAS5 levels were up-regulated in the MS patients, blood compared with healthy subjects in correlation with NR3C1 expression. Our findings suggest that GAS5 may play on important role in the molecular etiology and treatment of MS.

Long non-coding RNA GAS5 antagonizes the chemoresistance of pancreatic cancer cells through down-regulation of miR-181c-5p

ObjectiveTo explore the core mechanism of long non-coding RNA (lncRNA) growth arrest-specific transcript 5 (GAS5) in the regulation of multidrug resistance of pancreatic cancer cells. MethodsmRNA levels of GAS5, miR-181c-5p and Hippo pathway related genes were detected by quantitative real-time PCR (qRT-PCR). Protein levels of MDR-1, MST1, YAP and TAZ were measured by western blot. Cell viability was detected by MTT assay. The combination between GAS5 and miR-181c-5p was confirmed by RNA pull-down and RNA immunoprecipitation (RIP) assay. We also established pancreatic cancer-bearing mice model and analyzed tumor volumes. ResultsOur data showed GAS5 expression was significantly down-regulated, miR-181c-5p expression was significantly up-regulated in pancreatic cancer cells. Besides, Overexpresson of GAS5 obviously inhibited cell viability, while GAS5 knockdown showed the opposite outcome. Additionally, we also found that GAS5 negatively regulated miR-181c-5p, and miR-181c-5p dramatically promoted pancreatic cancer cell chemoresistance through inactivating the Hippo signaling. GAS5 regulated chemoresistance and Hippo pathway of pancreatic cancer cells via miR-181c-5p/Hippo. Finally, we confirmed that overexpression of GAS5 inhibited tumor growth in pancreatic cancer-bearing mice model. ConclusionGAS5 regualtes Hippo signaling pathway via miR-181c-5p to antagonize the development of multidrug resistance in pancreatic cancer cells.

An Oncolytic Adenovirus Expressing SNORD44 and GAS5 Exhibits Antitumor Effect in Colorectal Cancer Cells.

SNORD44 is a C/D box small nucleolar RNA, and exhibits low expression in breast cancer and head and neck squamous cell carcinoma tissues. Its host gene is growth arrest specific transcript 5 (GAS5), which is a long noncoding RNA. GAS5 is downregulated in colorectal cancer (CRC), and overexpression of GAS5 suppresses cell proliferation. However, the function of SNORD44 in CRC remains largely unknown, and the application of SNORD44 combined with GAS5 in CRC treatment has not been reported. In this study, the expression levels of SNORD44 and GAS5 were measured in CRC tissues by quantitative RT-PCR. The correlation between SNORD44 and GAS5 was evaluated by Pearson correlation analysis. An oncolytic adenovirus expressing SNORD44 and GAS5 (SPDD-UG) was constructed. The biological effects of SPDD-UG were investigated in CRC cell line SW620 and LS174T in vitro and in xenografts. The synergistic effect of rapamycin and SPDD-UG was explored in SW620 and LS174T cells and tumors. We demonstrated that SNORD44 expression level was markedly decreased in CRC tissues and positively correlated with GAS5 expression. SPDD-UG significantly inhibited SW620 and LS174T cell growth and induced cell apoptosis. Intratumoral injection of SPDD-UG significantly suppressed xenografts growth in nude mice. Moreover, the mechanistic target of rapamycin (mTOR) inhibitor, rapamycin, enhanced the antitumor effect through antagonizing the PI3K/Akt pathway activated by SPDD-UG. These results suggest that overexpression of SNORD44 and GAS5 by oncolytic adenovirus provides a promising method for CRC therapy.