The lncRNA-MALAT1/miR-330-3p Axis Promotes Growth and Metastasis of Gastric Cancer Through Regulation of Vascular Endothelial Growth Factor A: A Genetic and Cell Evaluation Study

SUMMARY: Overexpression of metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) in various tumor tissues and cell lines was found to promote tumor cell proliferation, migration, and invasion. However, the role of MALAT1 in gastric cancer (GC) is still unclear. We aimed to investigate the correlation between long-chain non-coding RNAs (lncRNAs), MALAT1, MicroRNAs (miRNA) and vascular endothelial growth factor A (VEGFA) in gastric cancer and to disclose underlying mechanism. The correlation between MALAT1 levels and clinical features was analyzed by bioinformatics data and human samples. The expression of MALAT1 was down regulated in AGS cells to detect the cell proliferation, migration, and invasion characteristics, as well as the effects on signal pathways. Furthermore, we validated the role of MALAT1/miR-330-3p axis in GC by dual luciferase reporter gene assays. Expression of MALAT1 was higher in cancer tissues than in para-cancerous tissues. The high MALAT1 level predicted malignancy and worse prognosis. Down-regulation of MALAT1 expression in AGS cells inhibited cell proliferation, migration, and invasion by targeting VEGFA. By dual luciferase reporter gene assay and miR-330-3p inhibitor treatment, we demonstrate that MALAT1 sponged miR-330-3p in GC, leading to VEGFA upregulation and activation of the mTOR signaling pathway. The MALAT1/miR-330-3p axis regulates VEGFA through the mTOR signaling pathway and promotes the growth and metastasis of gastric cancer.

Se descubrió que la sobreexpresión del transcrito 1 de adenocarcinoma de pulmón asociado a metástasis (MALAT1) en varios tejidos tumorales y líneas celulares promueve la proliferación, migración e invasión de células tumorales. Sin embargo, el papel de MALAT1 en el cáncer gástrico (CG) aún no está claro. Nuestro objetivo fue investigar la correlación entre los ARN no codificantes de cadena larga (lncRNA), MALAT1, los microARN (miARN) y el factor de crecimiento endotelial vascular A (VEGFA) en el cáncer gástrico y revelar el mecanismo subyacente. La correlación entre los niveles de MALAT1 y las características clínicas se analizó mediante datos bioinformáticos y muestras humanas. La expresión de MALAT1 se reguló negativamente en las células AGS para detectar las características de proliferación, migración e invasión celular, así como los efectos sobre las vías de señales. Además, validamos el papel del eje MALAT1/miR- 330-3p en GC mediante ensayos de genes indicadores de luciferasa dual. La expresión de MALAT1 fue mayor en tejidos cancerosos que en tejidos paracancerosos. El alto nivel de MALAT1 predijo malignidad y peor pronóstico. La regulación negativa de la expresión de MALAT1 en células AGS inhibió la proliferación, migración e invasión celular al apuntar a VEGFA. Mediante un ensayo de gen indicador de luciferasa dual y un tratamiento con inhibidor de miR-330-3p, demostramos que MALAT1 esponjaba miR-330-3p en GC, lo que lleva a la regulación positiva de VEGFA y la activación de la vía de señalización mTOR. El eje MALAT1/miR-330-3p regula VEGFA a través de la vía de señalización mTOR y promueve el crecimiento y la metástasis del cáncer gástrico.

Effect of quercetin's anti-breast cancer depending on presence of estrogen receptor via down-regulating long non-coding RNA MALAT-1 and its mechanism / 中国药理学通报

Aim To investigate the molecular mechanism by which quercetin inhibits the malignant behavior of breast cancer cells. Methods Breast cancer cell lines MCF-7 and MB231 were used as the research models. Lentiviral transfection was employed to establish tumor cells with high expression of ERa and MAL-AT-1. The expression of MALAT-1 was assessed using RT-qPCR,and ERa expression was determined through Western blot. Subsequently, CCK-8 assay and colony formation assay were conducted to evaluate cell proliferation. PI staining and adenovirus transfection were performed to observe the inhibitory effects of quercetin on breast cancer cell proliferation. Results 17|3-es-tradiol ( E2 ) promoted the proliferation of MCF-7 breast cancer cells, while 5 jjunol L quercetin reversed the promoting effect of E2 on proliferation ( P 0. 05 ) . Quercetin had no effect on MB231 breast cancer cells. Overexpression of ERa significantly inhibited the pro-proliferative effect of E2 on MB231-ERa cells, and quercetin further suppressed this effect. Additionally , quercetin inhibited the expression of MALAT-1. However,this inhibitory effect was reversed by overexpression of MALAT-1, leading to enhanced cell proliferation , cell cycle progression, and clonal formation a-bility. Conclusions Quercetin exerts its anti-tumor effects on breast cancer cells by regulating MALAT-1, dependent on the presence of estrogen receptor. Quercetin shows potential as a therapeutic drug for breast cancer targeting the estrogen receptor.

Clinical efficacy of autologous platelet rich gel in the treatment of type 2 diabetic foot patients and its effect on the expression of MALAT1 in peripheral blood mononuclear cells / 中国医师杂志

Objective:To observe the clinical efficacy of autologous platelet rich gel (APG) in the treatment of type 2 diabetic foot (DF) patients and the effect of APG on the expression of metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) in peripheral blood mononuclear cells (PBMCs).Methods:A total of 62 patients with DF admitted to the Affiliated Hospital of Kangda College of Nanjing Medical University from February 2021 to May 2022 were randomly divided into a control group (30 cases) and an observation group (32 cases) using a random number table method. The control group received ultrasound debridement and dressing change treatment, while the observation group received ultrasound debridement combined with APG treatment. After 6 weeks of treatment, the effective rate, transcutaneous oxygen partial pressure (TcPO 2), and serum tumor necrosis factor- α (TNF-α), interleukin-6 (IL-6), vascular endothelial growth factor (VEGF), hypoxia inducible factor α (HIF-1 α)and the level of MALAT1 expression in PBMCs of the two groups of patients were observed. The Pearson correlation analysis was used to investigate the relationship between the expression change of MALAT (△ MALAT1) and the total effective rate of treatment. Results:The total effective rate of the observation group was higher than that of the control group [93.75%(30/32) vs 73.33%(22/30), P<0.05]. After treatment, the systolic blood pressure (SBP), diastolic blood pressure (DBP), cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), fasting blood glucose (FPG), glycosylated hemoglobin (HbA 1c), urinary microalbumin/creatinine (UACR), uric acid (UA), white blood cells (WBC), TNF- α and IL-6 of both groups had decreased compared to before; HIF-1 α, VEGF and MALAT1 increased compared to before treatment (all P<0.05); After treatment, there was a statistically significant difference in UA, HIF-1α, VEGF, and MALAT1 between the observation group and the control group (all P<0.05). Pearson correlation analysis showed that Δ MALAT1 in DF patients was negatively correlated with TNF -α ( r=-0.61, P=0.02), IL-6 ( r=-0.52, P=0.04), WBC ( r=-0.53, P=0.03), and positively correlated with VEGF ( r=0.58, P=0.03) and HIF-1α ( r=0.54, P=0.03). The total effective rate of DF treatment was higher in the high change group of△ MALAT [88.37%(38/43) vs 73.68%(14/19), P<0.05]. There was no statistically significant difference in the incidence of adverse reactions between the two groups ( P>0.05). Conclusions:APG can significantly upregulate the expression of MALAT, improve wound tissue blood perfusion, wound angiogenesis, and inflammatory response, promote ulcer healing, and changes in MALAT expression can help determine the prognosis of DF.

Research on the lncRNA MALAT1 promoting the proliferation, migration and angiogenesis of retinal vascular endothelial cells in diabetic retinopathy through the molecular axis of miR-124-3p/SOX7 / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To investigate the effect of lncRNA MALAT1 on the proliferation, migration and angiogenesis of retinal vascular endothelial cells and its molecular mechanism.METHODS: The expression levels of lncRNA MALAT1 in plasma of normal control group, diabetic without retinopathy group and diabetic retinopathy group were detected by qPCR and the effect of glucose culture on the expression levels of lncRNA MALAT1 were detected by qPCR too. The expression level of miR-124-3p was detected by qRT-PCR; Western blotting was used to detect the expression level of SOX7; The targeting relationship between lncRNA MALAT1 and miR-124-3p, miR-124-3p and SOX7 were detected by the dual-luciferase reporter system; CCK-8 assay was used to detect cell proliferation activity; Transwell assay was used to detect the migration ability of cells; Angiogenesis of hRMECs cells was measured by in vitro tube formation assay.RESULTS:The expression level of lncRNA MALAT1 in plasma of diabetic retinopathy patients was significantly higher than that of diabetic without retinopathy group and normal control group(P&#x003C;0.001). In vitro glucose culture significantly promoted the expression of lncRNA MALAT1 in hRMECs cells, as well as the proliferation, migration and angiogenesis of hRMECs cells(all P&#x003C;0.05). Knockdown of lncRNA MALAT1 significantly inhibited the proliferation, migration and tubule formation of hRMECs cells(all P&#x003C;0.05). Dual-luciferase reporter gene assay showed that lncRNA MALAT1 targeted with miR-124-3p, and miR-124-3p targeted with SOX7. Overexpression of miR-124-3p significantly inhibited the proliferation, migration and tubule formation of hRMECs cells(all P&#x003C;0.05). Overexpression of lncRNA MALAT1+miR-124-3p, miR-124-3p+SOX7, and knockdown of lncRNA MALAT1+overexpression of SOX7 all significantly eliminated the inhibitory effect of hRMECs cells(all P&#x003C;0.05).CONCLUSION: lncRNA MALAT1 promote the proliferation, migration and angiogenesis of retinal endothelial cells in diabetic retinopathy by down-regulating the negative regulation of miR-124-3p on SOX7. Therefore, abnormal upregulation of lncRNA MALAT1 in patients with diabetic retinopathy is a potential biomarker.

Long non-coding RNA MALAT1 regulates cell proliferation and apoptosis via miR-135b-5p/GPNMB axis in Parkinson's disease cell model

BACKGROUNDS: Parkinson's disease (PD) is a common age-related neurodegenerative disorder worldwide. This research aimed to investigate the effects and mechanism underlying long non-coding RNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) in PD. METHODS: SK-N-SH and SK-N-BE cells were treated with MPP+ to establish the MPP+-stimulated cell model of PD, and MALAT1 expression was determined. Then, the effects of MALAT1 depletion on cell proliferation and apoptosis were determined in the MPP+-stimulated cell model of PD. Besides, the correlations between microRNA-135b-5p (miR-135b-5p) and MALAT1 or glycoprotein nonmetastatic melanoma protein B (GPNMB) in MPP+-stimulated cell model of PD were explored. RESULTS: MALAT1 was increasingly expressed and downregulation of MALAT1 promoted cell proliferation while inhibited apoptosis in MPP+-stimulated cells. Besides, miR-135b-5p was a target of MALAT1 and directly targeted to GPNMB. Further investigation indicated that suppression of MALAT1 regulated cell proliferation and apoptosis by miR-135b-5p/GPNMB axis. CONCLUSION: Our findings reveal that MALAT1/miR-135b-5p/GPNMB axis regulated cell proliferation and apoptosis in MPP+-stimulated cell model of PD, providing a potential biomarker and therapeutic target for PD.

LncRNA MALAT1 aggravates oxygen-glucose deprivation/reoxygenation-induced neuronal endoplasmic reticulum stress and apoptosis via the miR-195a-5p/HMGA1 axis

BACKGROUND: This study aimed to investigate the potential role and molecular mechanism of lncRNA metastasis associated lung adenocarcinoma transcript 1 (MALAT1) in cerebral ischemia/reperfusion injury. RESULTS: Using an oxygen-glucose deprivation/reoxygenation (OGD/R) cell model, we determined that the expression of MALAT1 was significantly increased during OGD/R. MALAT1 knockdown reversed OGD/R-induced apoptosis and ER stress. Mechanistically, MALAT1 promoted OGD/R-induced neuronal injury through sponging miR-195a-5p to upregulating high mobility group AT-hook1 (HMGA1). CONCLUSIONS: Collectively, these data demonstrate the mechanism underlying the invovlvement of MALAT1 in cerebral ischemia/reperfusion injury, thus providing translational evidence that MALAT1 may serve as a novel biomarker and therapeutic target for ischemic stroke.

MALAT1 is involved in type I IFNs-mediated systemic lupus erythematosus by up-regulating OAS2, OAS3, and OASL

Systemic lupus erythematosus (SLE) is an autoimmune disease associated with an aberrant activation of immune cells partly due to the dysfunction of cytokines such as type I interferons (IFNs). Long non-coding RNA MALAT1 has been found to play a pathogenic role in SLE; however, the underlying mechanisms are still poorly understood. Bioinformatics analysis showed the up-regulation of type I IFN downstream effectors OAS2, OAS3, and OASL (OAS-like) in CD4+ T cells, CD19+ B cells, and CD33+ myeloid cells in patients with active SLE compared to healthy participants. In this study, peripheral blood mononuclear cells (PBMCs), CD19+ B, and CD4+ T cells were isolated from active SLE patients and healthy participants. PCR was performed to quantify MALAT1, OAS2, OAS3, and OASL expression in immune cells. MALAT1, OAS2, OAS3, and OASL were knocked down in CD4+ T cells to investigate the regulatory effect of MALAT1 on the effectors and their involvement in type I IFNs-mediated inflammation. Results showed higher OAS2, OAS3, and OASL expression in active SLE patients. MALAT1 expression was positively correlated to OAS2, OAS3, and OASL expression in CD19+ B or CD4+ T cells. MALAT1 knockdown decreased OAS2, OAS3, and OASL expression. Treatment with IFN-α-2a increased the expression of TNF-α, IL-1β, and IFN-α in CD4+ T cells. However, knockdown of MALAT1, OAS2, OAS3, and OASL alone inhibited the effect of IFN-α-2a on TNF-α and IL-1β. This study suggested the involvement of MALAT1 in type I IFNs-mediated SLE by up-regulating OAS2, OAS3, and OASL.

Association of circulating long non-coding RNA MALAT1 in diagnosis, disease surveillance, and prognosis of acute ischemic stroke

We aimed to investigate the association of long non-coding RNA metastasis-associated lung adenocarcinoma transcript 1 (lnc-MALAT1) with acute ischemic stroke (AIS), and its association with disease severity, inflammation, and recurrence-free survival (RFS) in AIS patients. One hundred and twenty AIS patients and 120 controls were recruited. Venous blood samples from AIS patients (within 24 h after symptoms onset) and controls (at entry to study) were collected to detect plasma lnc-MALAT1 expression by real-time quantitative polymerase chain reaction. AIS severity was assessed by the National Institutes of Health Stroke Scale (NIHSS) score. Plasma concentrations of inflammation factors (including C-reactive protein (CRP), tumor necrosis factor α (TNF-α), interleukin (IL)-6, IL-8, IL-10, IL-17, and IL-22) were measured and RFS was calculated. lnc-MALAT1 expression was decreased in AIS patients compared to controls, and it had a close correlation with AIS (AUC=0.791, 95% CI: 0.735-0.846). For disease condition, lnc-MALAT1 expression negatively correlated with NIHSS score and pro-inflammatory factor expression (including CRP, TNF-α, IL-6, IL-8, and IL-22), while it positively correlated with anti-inflammatory factor IL-10 expression. Furthermore, lnc-MALAT1 expression was elevated in AIS patients with diabetes. For prognosis, no statistical correlation of lnc-MALAT1 expression with RFS was found, while a trend for longer RFS was observed in patients with lnc-MALAT1 high expression compared to those with lnc-MALAT1 low expression.

Long-chain non-coding RNA MALAT1 regulates paclitaxel resistance of breast cancer cells by targeting miR-485-3p / 南方医科大学学报

OBJECTIVE@#To investigate the role of long-chain non-coding RNA MALAT1 in modulating paclitaxel resistance in breast cancer cells.@*METHODS@#Breast cancer SK-BR-3 cells were treated with gradient concentrations of paclitaxel to induce paclitaxel resistance of the cells. The resistant cells were transfected with si-NC, si-MALAT1, pcDNA, pcDNA-MALAT1, miRNC, miR-485-3p mimics, si-MALAT1+anti-miR-NC, or si-MALAT1+anti-miR-485-3p liposomes. Following the transfections, the cells were examined for changes in IC of paclitaxel using MTT assay; the protein expression of P-gp, Bcl-2 and Bax were detected with Western blotting, and a dual luciferase reporter assay was used to detect the binding of MALAT1 to miR-485-3p.@*RESULTS@#Compared with paclitaxel-sensitive SK-BR-3 cells, paclitaxel-resistant SK-BR-3 cells showed significantly increased the IC of paclitaxel with up-regulated MALAT1 expression and down-regulated miR-485-3p expression ( < 0.05). Silencing MALAT1 or overexpressing miR-485-3p obviously lowered the IC of paclitaxel and the expression of P-gp and Bcl-2 and increased the expression of Bax in SK-BR-3/PR cells ( < 0.05). miR-485-3p was identified as the target of MALAT1, and inhibiting miR-485-3p significantly reverse the effect of MALAT1 silencing on IC of paclitaxel and the expressions of P-gp, Bcl-2 and Bax in SK-BR-3/PR cells ( < 0.05).@*CONCLUSIONS@#MALAT1 can modulate paclitaxel resistance in breast cancer cells possibly by targeting miR-485-3p to down-regulate P-gp and Bcl-2 and up-regulate Bax.

Screening of miRNAs associated with lymph node metastasis in Her-2-positive breast cancer and their relationship with prognosis / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

The aim of this study was to identify some biomarkers for predicting lymph node metastasis and prognosis of human epidermal growth factor receptor 2 (Her-2)-positive breast cancer (BC). We analyzed correlations between microRNAs (miRNAs) and the prognosis of patients with BC based on data collected from The Cancer Genome Atlas (TCGA) database. The expression levels of miR-455, miR-143, and miR-99a were measured in clinical samples of Her-2-positive BC patients with different degrees of lymph node metastasis. We investigated the impacts of overexpressed miR-455 on the proliferation and invasiveness of MDA-MB-453 cells and measured its effects on the expression of long non-coding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) by quantitative real-time polymerase chain reaction (qRT-PCR). The expression of miR-455 was significantly and positively correlated to the prognosis and overall survival (OS) of the BC (P=0.028), according to TCGA information. The expression level of miR-455 was positively correlated with OS and relapse-free survival (RFS) of patients with Her-2-positive BC, and was negatively correlated with the number of metastatic lymph nodes (P<0.05). Transwell assay suggested that MDA-MB-453 cells became much less invasive (P<0.01) after being transfected with miR-455 mimics. During the qRT-PCR, the expression level of MALAT1 declined significantly after transfection (P<0.01). Overexpressed miR-455 significantly inhibited the proliferation and migration of MDA-MB-453 cells and the expression of MALAT1. We conclude that miR-455 may be a useful potential biomarker for forecasting lymph node metastasis and the prognosis of Her-2-positive BC patients. miR-455 may play an important role in lymph node metastasis of BC by interacting with MALAT1.

Retracted: Role of LncRNA MALAT-1 on Induced Submandibular Gland Carcinoma in Albino Rats Treated with Induced Pluripotent Stem Cells (Histological and Immunhistochemical Study)

Salivary gland tumors show complex histopathology and the treatment depends mainly on the stage of cancer. Induced pluripotent stem cells (iPS) have a great role in regenerative medicine as they can generate pluripotent stem cells from any available cell types as fibroblast. Thus, the aim of this work is to investigate the possible therapeutic effect of (iPS) on induced salivary gland cancer through evaluation of the silent information regulators of sirtuin-1 (Sirt-1), Tgf-β genes and their protein expressions in addition to LncRNA MALAT-1 expression. Thirty male albino rats were employed and divided into three groups (ten rats for each group), group 1 (control): Rats were injected with phosphate buffered saline (PBS), group II induced squamous cell carcinoma (SCC): rats were injected with squamous carcinoma cells (SCC), group III (induced SCC/iPS): SCC treated rats treated with 5 × 106 iPS cells. Submandibular specimens were taken and prepared for histological, histochemical and immunohistochemical studies for Bax and TGF-β3 protein. Also, Real time PCR was performed for Sirt-1, Tgf-β, and MALAT-1 LncRNA genes expression. SIRT-1 and TGF-β protein level expression was assessed by western blot technique. Group III (iPS treated group) revealed more or less normal acinar structure with normal rearrangement of acini and normal intralobular ducts with an increase in their number. In the iPS treated group there was increasing in the amount of mucopoly saccharide in the acinar cells and intensity of BAX immunostaining while, TGF-β3 was decreased in its intensity in comparison to that of the cancer treated group. In addition to Sirt-1, Tgf-β, and MALAT-1 LncRNA expressions were increased in cancer group compared to iPS treated and control groups. Induced pluripotent stem cells play a potential therapeutic role in treatment of induced submandibular gland carcinoma. Retraction Notice: This paper has been retracted from the journal after receipt of written complains. This journal is determined to promote integrity in research publication. This retraction is in spirit of the same. After formal procedures editor(s) and publisher have retracted this paper on 19th August-2019. Related policy is available here: http://goo.gl/lI77Nn

Curcumin combining with si-MALAT1 inhibits the invasion and migration of colon cancer SW480 cells

To study the effect of small interfering RNA targeting metastasis-associated lung adenocarcinoma transcript1 (si-MALAT1) combining with curcumin on the invasion and migration abilities of human colon cancer SW480 cells, and to explore the involved molecular mechanism. The recombinant lentiviral vector expressing si-MALAT1 was constructed, and its titer was determined by gradient dilution method. The colon cancer SW480 cells with stable expression of si-MALAT1 was established, followed by treatment with curcumin at different concentrations. The effect of curcumin or si-MALAT1 alone and the combination of the two on the cell activity was detected by MTT assay. The cell invasion and migration abilities were detected by transwell and scratch-wound assay. The relative expression level of MALAT1 was detected by RT-qPCR. The protein expression was determined by Western blot analysis. The IC50 of curcumin alone was 77.69 mmol/L, which was 51.17 mol/L when combined with curcumin and random sequence. The IC50 of curcumin was 30.02 mmol/L when combined with si-MALAT1. The increased susceptibility multiples was 2.58. The wound healing rates were 30.9% and 67.5% after treatment with si-MALAT1 combined with curcumin for 24 hrs and 48 hrs, respectively. The numbers of invasion cells were 200±12, 162±13, 66±8, 53±4 and 16±3 after treatment with si-MALAT1 combined with curcumin for 48 hrs. The relative expression level of lncRNA-MALAT1 in the curcumin group was 68%, and the relative expression level of lncRNA-MALAT1 in si-MALAT1group was 56%, and that for the combination treatment group was about 21%. The protein expression levels of β- catenin, c-myc and cyclinD1 were significantly down-regulated upon treatment with certain concentration of si-MALAT1 alone or combined with curcumin.si-MALAT1 could significantly inhibit the invasion and migration of SW480 cells by enhancing the sensitivity of SW480 cells to curcumin. The mechanism involved mignt be related to the down-regulation of β-catenin, c-myc and cyclinD1 proteins.

Long non-coding RNA MALAT1 enhances the apoptosis of cardiomyocytes through autophagy inhibition by regulating TSC2-mTOR signaling

BACKGROUND: Our previous study showed that knockdown of long noncoding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) attenuated myocardial apoptosis in mouse acute myocardial infarction (AMI). This study aims to explore whether MALAT1 enhanced cardiomyocyte apoptosis via autophagy regulation and the underlying mechanisms of MALAT1 regulating autophagy. METHODS: Cardiomyocytes were isolated from neonatal mice and then stimulated with hypoxia/reoxygenation (H/R) injury to mimic AMI. The autophagy level was assessed using GFP-LC3 immunofluorescence and western blot analysis of autophagy-related proteins. RNA pull-down and RNA immunoprecipitation (RIP) was performed to analyze the binding of MALAT1 and EZH2. Chromatin immunoprecipitation (ChIP) assay was performed to analyze the binding of TSC2 promoter and EZH2. The cell apoptosis was evaluated using TUNEL staining and western blot analysis of apoptosis-related proteins. RESULTS: H/R injury increased MALAT1 expression in cardiomyocytes. Furthermore, MALAT1 overexpression inhibited, whereas MALAT1 knockdown enhanced the autophagy of cardiomyocytes. Moreover, MALAT1 overexpression recruited EZH2 to TSC2 promoter regions to elevate H3K27me3 and epigenetically inhibited TSC2 transcription. Importantly, TSC2 overexpression suppressed mTOR signaling and then activated the autophagy. Further results showed that MALAT1 inhibited proliferation and enhanced apoptosis of cardiomyocytes through inhibiting TSC2 and autophagy. CONCLUSION: These findings demonstrate that the increased MALAT1 expression induced by H/R injury enhances cardiomyocyte apoptosis through autophagy inhibition by regulating TSC2-mTOR signaling.

Relationship between serum long-chain non-coding RNA MALAT1 and AFAP1 -AS1,and clinicopathological features and prognosis of nasopharyngeal carcinoma / 实用肿瘤学杂志

Objective The objective of this study was to investigate the relationship between serum long-chain non-cod-ing RNA MALAT1 and AFAP1-AS1 and clinicopathological features,and prognosis of nasopharyngeal carcinoma(NPC). Methods A total of 136 patients with nasopharyngeal carcinoma confirmed by pathology in our hospital were selected from April 2013 to June 2015. During the same time,54 outpatients for health examination in our hospital were selected as the control group and nasopharynge-al carcinoma group. Real-time fluorescence reverse transcription analysis was used to analyze the expression of lncRNA MALAT1 and AFP1-AS1. The relationship between the expression of lncRNA MALAT1 and AFP1-AS1,and clinicopathological characteris-tics was analyzed by χ2 test. Log-rank assay was used to analyze serum long-chain non-coding RNA MALAT1 and prognostic differences in patients with different expression levels of AFAP1-AS1. Results Compared with the control group,the serum levels of RNA MALAT1 and RNA AFAP1-AS1 in the nasopharyngeal carcinoma group were significantly increased(P<0. 001);The expres-sions of lncRNA MALAT1 and AFAP1-AS1 was not related to age(P>0. 05);The maximum diameter of the tumor was≥5 cm,the pathological stage was higher,the TNM stage was higher,the deeper in the infiltration depth,the infiltration of lymphatic vessels,the lymph node metastasis,and the recurrence and the higher in high expressive rates of lncRNA MALAT1 and AFAP1 -AS1 ( P <0. 05). The 2-year survival rate and survival time of lncRNA MALAT1 and AFAP1-AS1 in the low expression group were signifi-cantly higher than those of the high expression group(P<0. 001);Multivariate Cox stepwise regression analysis showed that low ex-pression of lncRNA MALAT1(HR=0. 52,95% CI:0. 37~0. 81)and low expression of lncRNA AFAP1-AS1(HR=0. 56,95% CI:0. 51~0. 83)were independent prognostic protective factors for NPC patients(P<0. 001). Conclusion The serum long-chain non-coding RNA MALAT1 and AFAP1-AS1 are elevated in patients with NPC,and are positively correlated with malignant progression of NPC. NPC patients with low expression of lncRNA MALAT1 and AFAP1-AS1 serum have a good prognosis;MALAT1 and AFAP1 -AS1 can be used as new markers for the diagnosis of nasopharyngeal carcinoma.

A study on genetic polymorphisms of rs600231 and rs4102217 loci in promoter of MALAT1 gene in Guangxi population / 临床检验杂志

Objective@#To investigate the single nucleotide polymorphisms (SNPs) of rs600231A/G and rs4102217 G/C in the promoter region of MALAT1 (metastasis associated in lung adenocarcinoma transcript 1) gene in the healthy population of Guangxi district and analyze the differences in the population among different regions. @*Methods@#The genotypes of rs600231A/G and rs4102217G/C of 207 healthy individuals in Guangxi were detected by SNPscan high-throughput technique. The genotype and allele frequency distributions were analyzed statistically with the data of HapMap-CEU (European population), HapMap-HCB (Beijing Han population), HapMap-JPT (Japanese population) and HapMap-YRI (African population) published by Human genome Haplotype Map (HapMap). @*Results@#There were three genotypes of AA (38.2%), AG (46.4%) and GG (15.4%) in rs600231A/G, and the differences were significantly different compared with the polymorphism of Japan and Africa population (HapMap-JPT and HapMap-YRI) (P＜0.05). Compared with HapMap-CEU, the genotype difference was not statistically significant (P＞0.05), but the allele distribution was statistically different (P＜0.05). The rs4102217 G/C polymorphism contained GG(75.4%), CG(23.2%) and CC(1.4%), and the polymorphisms were significantly different from those in European and Japanese populations (P＜0.05). There was no significant difference between gender in the polymorphisms of the two loci (P＞0.05). @*Conclusion@#The polymorphisms of rs600231A/G and rs4102217G/C in the MALAT1 promoter region were found in Guangxi healthy population, and the distribution of polymorphisms may be different in the population of various regions. @*@#

MALAT1 upregulates SMYD3 by competition with miR-124 and promotes proliferation and migration of breast cancer cells / 中国药科大学学报

@#To investigate whether lncRNA MALAT1 affects the migration and proliferation of breast cancer cells through the regulation with histone methyltransferase SMYD3, the endogenous MALAT1 in the MCF-7 and MDA-MB-231 breast cancer cells were knocked down by siRNA, and then the migration and proliferation of cells were detected by wound healing migration and MTT assay. The effects of si-MALAT1 on the mRNA and protein levels of miRNA-124, SMYD3 and its downstream genes were detected by Real time PCR and Western blot. The results showed that siRNA-targeted knockdown of MALAT1 reduced the migration and proliferation of breast cancer cells, and inhibited the transcriptional expression of SMYD3 and its downstream genes, including N-cadherin, MYL9, MMP9 and CYR61, and up-regulated miR-124. Overexpression of miR-124 reduced the expression of SMYD3 in breast cancer cells, and knockdown of MALAT1 attenuated the promotion of SMYD3 protein expression by miR-124 inhibitors. In addition, SMYD3 overexpression activated MALAT1 transcription, whereas siRNA interference with SMYD3 downregulated MALAT1. These results indicate that LncRNA MALAT1 acted as a competing endogenous RNA(ceRNA)of miR-124 to regulate expression of SMYD3 in breast cancer cells, and SMYD3 can activate the transcription of MALAT1, which will affect the proliferation and migration of breast cancer cells.

Long Noncoding RNA MALAT1 Regulates Hepatocellular Carcinoma Growth Under Hypoxia via Sponging MicroRNA-200a

PURPOSE: Hepatocellular carcinoma (HCC) is a common cancer worldwide. Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), a long noncoding RNA (lncRNA), has been reported to be aberrantly expressed in hypoxic cancer cells. MALAT1 plays a significant role in many malignancies, including HCC. The aim of this study was to explore the role of MALAT1 in hypoxic HCC cells and its underlying regulatory mechanism. MATERIALS AND METHODS: Quantitative reverse transcription PCR (qRT-PCR) assay was performed to detect the mRNA levels of MALAT1 and microRNA-200a (miR-200a) in HCC cells. Cell invasion and migration ability were evaluated by Transwell assay. Starbase v2.0 and luciferase reporter assay were employed to identify the association between MALAT1 and miR-200a. Cell proliferation and apoptosis were measured by MTT assay and flow cytometry, respectively. RESULTS: MALAT1 levels were significantly upregulated in HCC cells under hypoxia. Hypoxia promoted proliferation, migration, and invasion, and blocked apoptosis in Hep3B cells, which were weakened by knockdown of MALAT1. Starbase v2.0 showed that MALAT1 and miR-200a have a complementarity region, and luciferase reporter assay verified that MALAT1 interacted with miR-200a in Hep3B cells. Moreover, MALAT1 negatively regulated the expression of miR-200a. miR-200a levels were dramatically downregulated in HCC cells under hypoxia. Upregulation of miR-200a inhibited proliferation, migration, and invasion, and induced apoptosis in Hep3B cells under hypoxia. Interestingly, downregulation of miR-200a partially reversed the tumor-suppressive effect of knockdown of MALAT1 on Hep3B cells in hypoxic condition. CONCLUSION: LncRNA MALAT1 was involved in proliferation, migration, invasion, and apoptosis by interacting with miR-200a in hypoxic Hep3B cells, revealing a new mechanism of MALAT1 involved in hypoxic HCC progression.

LncRNA MALAT1/MiR-145 Adjusts IL-1β-Induced Chondrocytes Viability and Cartilage Matrix Degradation by Regulating ADAMTS5 in Human Osteoarthritis

PURPOSE: Accumulating evidence suggests that microRNA-145 (miR-145) plays an important role in osteoarthritis (OA), which is a chronic progressive joint disease. Long noncoding RNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) promotes metastasis in cancers and functions as a sponge for miR-145. However, the role of MALAT1/miR-145 in OA pathogenesis has not yet been elucidated. MATERIALS AND METHODS: The expression of MALAT1 and miR-145 was examined by quantitative real-time PCR; the interaction between miR-145, MALAT1 and a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) 5 was verified by luciferase reporter assay. Correlations among MALAT1, miR-145, and ADAMTS5 were analyzed by Spearman rank analysis. Chondrocytes viability and cartilage extracellular matrix (ECM) degradation were investigated with cell viability assay and Western blotting analyzing expression of ADAMTS5, collagen type 2 alpha 1 (COL2A1), aggrecan (ACAN), and cartilage oligomeric matrix protein (COMP). RESULTS: MALAT1 was upregulated, and miR-145 was downregulated in OA samples and IL-1β-induced chondrocytes. Mechanically, miR-145 could directly bind to MALAT1 and ADAMTS5. Moreover, miR-145 expression was negatively correlated with MALAT1 and ADAMTS5 expression in OA patients, whereas MALAT1 and ADAMTS5 expression was positively correlated. Functionally, overexpression of MALAT1 inhibited chondrocyte viability and promoted cartilage ECM degradation in IL-1β-induced chondrocytes. In support thereof, MALAT1 silencing and miR-145 upregulation exerted the opposite effect in IL-1β-induced chondrocytes. Moreover, the effect of MALAT1 was counteracted by miR-145 upregulation, and ADAMTS5 restoration could abate miR-145 effects. CONCLUSION: An MALAT1/miR-145 axis contributes to ECM degradation in IL-1β-induced chondrocytes through targeting ADAMTS5, suggesting that MALAT1/miR-145/ADAMTS5 signaling may underlie human OA pathogenesis.

Diagnostic value of serum carcinoembryonic antigen and carbohydrate antigen 724 combined with long non-coding RNA MALAT1 detection in gastric cancer / 肿瘤研究与临床

Objective To explore the diagnostic value of serum carcinoembryonic antigen (CEA), carbohydrate antigen 724 (CA724) combined with long non-coding RNA MALAT1 in gastric cancer. Methods A total of 100 patients with gastric cancer diagnosed in Changzhou Cancer Hospital, Soochow University from March 2013 to February 2018 were collected as the case group, and 100 healthy people during the same period in our hospital were collected as the control group. The levels of serum CEA, CA724 were detected by using chemiluminesent immunoassay assay, and the relative expression of MALAT1 was detected by using real-time fluorescence quantification polymerase chain reaction (PCR). The relationships between CEA, CA724, MALAT1 and the clinicopathological features of gastric cancer were analyzed. Receiver operating characteristic (ROC) curve was used to analyze the diagnostic value of CEA, CA724 and MALAT1 in patients with gastric cancer. The odds ratio (OR) and 95％ confidence interval (CI) were calculated by using logistic regression. Results The levels of serum CEA, CA724 and MALAT1 in the case group were higher than those in the control group [(3.08 ±0.21) ng/ml vs. (0.74 ±0.11) ng/ml, t= 3.814, P= 0.002; (4.28 ±0.17) U/ml vs. (0.51± 0.07) U/ml, t=4.703, P<0.01; (113.9±3.9) vs. (36.1±1.2), t=7.160, P<0.01 respectively], and the three indexes were related to the pathological types and TNM staging of gastric cancer (all P< 0.05), and the most significant increase was seen in tubular adenocarcinoma patients and stage Ⅲ-Ⅳ patients. ROC curve analysis showed that the area under curve (AUC) of serum CEA, CA724 and MALAT1 in the differential diagnosis between the gastric cancer and the healthy people were 0.675 (95％CI 0.578-0.755, P= 0.001), 0.865 (95％CI 0.800-0.922, P< 0.01) and 0.847 (95％CI 0.771-0.911, P< 0.01), and the sensitivity was 69.1％, 80.2％, 85.8％, and specificity was 63.5％, 77.4％, 74.5％, respectively. AUC of combination of the three indicators for diagnosis of gastric cancer was 0.887 (95％CI 0.821-0.949, P<0.001), and the sensitivity was 84.3％ and the specificity was 91.9％. Logistic regression results showed that high levels of serum CEA, CA724 and MALAT1 were risk factors for gastric cancer. After adjusting for age, sex, smoking history and drinking history, high levels of serum CEA, CA724 and MALAT1 remained the independent risk factors for gastric cancer. Conclusion The combined detection of serum CEA, CA724 and MALAT1 can be used to predict the risk of gastric cancer, and the three have a value for the diagnosis of gastric cancer, which is worthy of clinical application.

Long chain non-coding RNA MALAT-1 gene knockdown inhibits growth and migration and promotes apoptosis of human laryngeal squamous cell carcinoma Hep-2 cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of knocking down long chain non-coding RNA MALAT-1 gene on the biologicalbehaviors of human laryngeal squamous cell carcinoma Hep-2 cells.</p><p><b>METHODS</b>With immortalized nasopharyngeal epithelial(NPE) cell line NP-69 as the reference, MALAT1 expression in FaDu, Hep-2 and nasopharyngeal carcinoma CNE-2Z cells weredetected using real-time PCR. Hep-2 cells were transfected with shmalat1 lentivirus and the expression of MALAT1 wasdetected. MTT assay, flow cytometry, Transwell assay and M Atrigel invasiveness test were used to evaluate the effect ofMALAT-1 knockdown on the proliferation, cell cycle, cell apoptosis, migration, and invasiveness of Hep-2 cells.</p><p><b>RESULTS</b>Compared with NP-69 cells, Hep-2 cells, FaDu cells, and CNE-2Z cells all showed significantly increased MALAT-1expression. In Hep-2 cells, knockdown of MALAT-1 significantly inhibited the cell proliferation, increased the cell percentagein S phase ( < 0.01), decreased the cell percentage in G2/M phase ( < 0.01), and attenuated the migration and invasiveness of thecells.</p><p><b>CONCLUSIONS</b>MALAT-1 is over-expressed in laryngeal squamous cell carcinoma, and knocking down MALAT-1 gene cansignificantly suppress the proliferation, invasion and migration and promotes apoptosis of the cancer cells.</p>