scholarly journals BET bromodomain inhibitors PFI-1 and JQ1 are identified in an epigenetic compound screen to enhance C9ORF72 gene expression and shown to ameliorate C9ORF72-associated pathological and behavioral abnormalities in a C9ALS/FTD model

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Esteban Quezada ◽  
Claudio Cappelli ◽  
Iván Diaz ◽  
Nur Jury ◽  
Nicholas Wightman ◽  
...  
Keyword(s):  
Gene Expression ◽  
Molecular Mechanisms ◽  
Luciferase Reporter ◽  
Loss Of Function ◽  
Protein Levels ◽  
Hexanucleotide Repeat ◽  
Rna Foci ◽  
Behavioral Abnormalities ◽  
Bet Inhibitors

Abstract Background An intronic GGGGCC (G4C2) hexanucleotide repeat expansion (HRE) in the C9ORF72 gene is the most common cause of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), referred to as C9ALS/FTD. No cure or effective treatment exist for C9ALS/FTD. Three major molecular mechanisms have emerged to explain C9ALS/FTD disease mechanisms: (1) C9ORF72 loss-of-function through haploinsufficiency, (2) dipeptide repeat (DPR) proteins mediated toxicity by the translation of the repeat RNAs, and more controversial, (3) RNA-mediated toxicity by bidirectional transcription of the repeats that form intranuclear RNA foci. Recent studies indicate a double-hit pathogenic mechanism in C9ALS/FTD, where reduced C9ORF72 protein levels lead to impaired clearance of toxic DPRs. Here we explored whether pharmacological compounds can revert these pathological hallmarks in vitro and cognitive impairment in a C9ALS/FTD mouse model (C9BAC). We specifically focused our study on small molecule inhibitors targeting chromatin-regulating proteins (epidrugs) with the goal of increasing C9ORF72 gene expression and reduce toxic DPRs. Results We generated luciferase reporter cell lines containing 10 (control) or ≥ 90 (mutant) G4C2 HRE located between exon 1a and 1b of the human C9ORF72 gene. In a screen of 14 different epidrugs targeting bromodomains, chromodomains and histone-modifying enzymes, we found that several bromodomain and extra-terminal domain (BET) inhibitors (BETi), including PFI-1 and JQ1, increased luciferase reporter activity. Using primary cortical cultures from C9BAC mice, we further found that PFI-1 treatment increased the expression of V1-V3 transcripts of the human mutant C9ORF72 gene, reduced poly(GP)-DPR inclusions but enhanced intranuclear RNA foci. We also tested whether JQ1, an BETi previously shown to reach the mouse brain by intraperitoneal (i.p.) injection, can revert behavioral abnormalities in C9BAC mice. Interestingly, it was found that JQ1 administration (daily i.p. administration for 7 days) rescued hippocampal-dependent cognitive deficits in C9BAC mice. Conclusions Our findings place BET bromodomain inhibitors as a potential therapy for C9ALS/FTD by ameliorating C9ORF72-associated pathological and behavioral abnormalities. Our finding that PFI-1 increases accumulation of intranuclear RNA foci is in agreement with recent data in flies suggesting that nuclear RNA foci can be neuroprotective by sequestering repeat transcripts that result in toxic DPRs.

scholarly journals miR-19a protects cardiomyocytes from hypoxia/reoxygenation-induced apoptosis via PTEN/PI3K/p-Akt pathway

2017 ◽  
Vol 37 (6) ◽  
Author(s):  
Guochao Sun ◽  
Ying Lu ◽  
Yingxia Li ◽  
Jun Mao ◽  
Jun Zhang ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Ischemic Injury ◽  
Cardiomyocyte Apoptosis ◽  
Luciferase Reporter ◽  
H9c2 Cells ◽  
Rat Cardiomyocytes ◽  
Protein Levels ◽  
Myocardial Ischemic Injury ◽  
Hypoxia Reoxygenation

miRNAs have been implicated in processing of cardiac hypoxia/reoxygenation (H/R)-induced injury. Recent studies demonstrated that miR-19a might provide a potential cardioprotective effect on myocardial disease. However, the effect of miR-19a in regulating myocardial ischemic injury has not been previously addressed. The present study was to investigate the effect of miR-19a on myocardial ischemic injury and identified the potential molecular mechanisms involved. Using the H/R model of rat cardiomyocytes H9C2 in vitro, we found that miR-19a was in low expression in H9C2 cells after H/R treatment and H/R dramatically decreased cardiomyocyte viability, and increased lactate dehydrogenase (LDH) release and cardiomyocyte apoptosis, which were attenuated by co-transfection with miR-19a mimic. Dual-luciferase reporter assay and Western blotting assay revealed that PTEN was a direct target gene of miR-19a, and miR-19a suppressed the expression of PTEN via binding to its 3′-UTR. We further identified that overexpression of miR-19a inhibited the expression of PTEN at the mRNA and protein levels. Moreover, PTEN was highly expressed in H/R H9C2 cells and the apoptosis induced by H/R was associated with the increase in PTEN expression. Importantly, miR-19a mimic significantly increased p-Akt levels under H/R. In conclusion, our findings indicate that miR-19a could protect against H/R-induced cardiomyocyte apoptosis by inhibiting PTEN /PI3K/p-Akt signaling pathway.

scholarly journals miR-362-3p acts as a tumor suppressor by targeting SERBP1 in ovarian cancer

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Shujun Cao ◽  
Na Li ◽  
Xihong Liao
Keyword(s):  
Ovarian Cancer ◽  
Cell Proliferation ◽  
Cancer Progression ◽  
Target Gene ◽  
Molecular Mechanisms ◽  
Gynecological Cancer ◽  
Luciferase Reporter ◽  
Loss Of Function

Abstract Background Ovarian cancer is the leading lethal gynecological cancer and is generally diagnosed during late-stage presentation. In addition, patients with ovarian cancer still face a low 5-year survival rate. Thus, innovative molecular targeting agents are required to overcome this disease. The present study aimed to explore the function of miR-362-3p and the underlying molecular mechanisms influencing ovarian cancer progression. Methods The expression levels of miR-362-3p were determined using qRT-PCR. Gain-of-function and loss-of-function methods were used to detect the effects of miR-362-3p on cell proliferation, cell migration, and tumor metastasis in ovarian cancer. A luciferase reporter assay was performed to confirm the potential target of miR-362-3p, and a rescue experiment was employed to verify the effect of miR-362-3p on ovarian cancer by regulating its target gene. Results miR-362-3p was significantly downregulated in ovarian cancer tissues and cell lines. In vitro, our data showed that miR-362-3p suppressed cell proliferation and migration. In vivo, miR-362-3p inhibited ovarian cancer growth and metastasis. Mechanistically, SERBP1 was identified as a direct target and functional effector of miR-362-3p in ovarian cancer. Moreover, SERBP1 overexpression rescued the biological function of miR-362-3p. Conclusions Our data reveal that miR-362-3p has an inhibitory effect on ovarian cancer. miR-362-3p inhibits the development and progression of ovarian cancer by directly binding its target gene SERBP1.

scholarly journals Long Non-Coding RNA FOXD1-AS1 Promotes the Progression and Glycolysis of Nasopharyngeal Carcinoma by Sustaining FOXD1 Expression

2020 ◽  
Author(s):  
Zhanwang Wang ◽  
Dong He ◽  
Yuxing Zhu ◽  
Xueying Hu ◽  
Yi Jin ◽  
...  
Keyword(s):  
Nasopharyngeal Carcinoma ◽  
Molecular Mechanisms ◽  
Bioinformatics Analysis ◽  
Regulatory Role ◽  
Loss Of Function ◽  
Over Expression ◽  
Protein Levels ◽  
Non Coding Rna

Abstract Background: Increasing evidence have emphasized the importance of long non-coding RNAs (lncRNAs) in various human cancers progression. Forkhead box D1 antisense RNA1 (FOXD1-AS1) is a novel lncRNA and plays vital regulatory role in diverse biological processes of cancers. However, the biological function, molecular mechanism and clinical significance of FOXD1-AS1 in nasopharyngeal carcinoma is still unknown.Methods: Comprehensive bioinformatics analysis and qRT-PCR was conducted to detect the expression level of FOXD1-AS1. Loss-of-function and gain-of-function experiments were performed to verify the functions of FOXD1-AS1 in proliferation, migration, invasion, apoptosis and glycolysis of nasopharyngeal carcinoma in vitro and in vivo. Further bioinformatics analysis and experiments were carried out to explore the underlying molecular mechanisms of FOXD1-AS1. Results: FOXD1-AS1 was significantly overexpressed in nasopharyngeal carcinoma and associated with poor survival in patients. Knockdown of FOXD1-AS1 significantly inhibited cell proliferation, migration, invasion and glycolysis, and promotes apoptosis in nasopharyngeal carcinoma, whereas over-expression of FOXD1-AS1 has the opposite effect. Mechanistically, we found that FOXD1-AS1 could upregulate the expression of FOXD1 through stabilizing the FOXD1 expression at mRNA and protein levels, and FOXD1 increased the glycolysis level by transcriptionally upregulating the expression of LDHA, PKM and ENO1, thus playing an oncogenic role in nasopharyngeal carcinoma progression. Conclusion: FOXD1-AS1 plays a critical regulatory role in nasopharyngeal carcinoma. The identified FOXD1-AS1/FOXD1 axis may serve as a potential prognostic biomarker and therapeutic target for patients with nasopharyngeal carcinoma.

scholarly journals M6A-mediated upregulation of LINC00958 increases lipogenesis and acts as a nanotherapeutic target in hepatocellular carcinoma

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Xueliang Zuo ◽  
Zhiqiang Chen ◽  
Wen Gao ◽  
Yao Zhang ◽  
Jinguo Wang ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Cell Lines ◽  
Molecular Mechanisms ◽  
Xenograft Model ◽  
Systemic Administration ◽  
Luciferase Reporter ◽  
Loss Of Function ◽  
Poor Overall Survival

Abstract Background Long non-coding RNAs (lncRNAs) possess significant regulatory functions in multiple biological and pathological processes, especially in cancer. Dysregulated lncRNAs in hepatocellular carcinoma (HCC) and their therapeutic applications remain unclear. Methods Differentially expressed lncRNA profile in HCC was constructed using TCGA data. LINC00958 expression level was examined in HCC cell lines and tissues. Univariate and multivariate analyses were performed to demonstrate the prognostic value of LINC00958. Loss-of-function and gain-of-function experiments were used to assess the effects of LINC00958 on cell proliferation, motility, and lipogenesis. Patient-derived xenograft model was established for in vivo experiments. RNA immunoprecipitation, dual luciferase reporter, biotin-labeled miRNA pull-down, fluorescence in situ hybridization, and RNA sequencing assays were performed to elucidate the underlying molecular mechanisms. We developed a PLGA-based nanoplatform encapsulating LINC00958 siRNA and evaluated its superiority for systemic administration. Results We identified a lipogenesis-related lncRNA, LINC00958, whose expression was upregulated in HCC cell lines and tissues. High LINC00958 level independently predicted poor overall survival. Functional assays showed that LINC00958 aggravated HCC malignant phenotypes in vitro and in vivo. Mechanistically, LINC00958 sponged miR-3619-5p to upregulate hepatoma-derived growth factor (HDGF) expression, thereby facilitating HCC lipogenesis and progression. METTL3-mediated N6-methyladenosine modification led to LINC00958 upregulation through stabilizing its RNA transcript. A PLGA-based nanoplatform loaded with si-LINC00958 was developed for HCC systemic administration. This novel drug delivery system was controlled release, tumor targeting, safe, and presented satisfactory antitumor efficacy. Conclusions Our results delineate the clinical significance of LINC00958 in HCC and the regulatory mechanisms involved in HCC lipogenesis and progression, providing a novel prognostic indicator and promising nanotherapeutic target.

scholarly journals N6-Methyladenosine Methyltransferase METTL3 Promotes Angiogenesis and Atherosclerosis by Upregulating the JAK2/STAT3 Pathway via m6A Reader IGF2BP1

2021 ◽  
Vol 9 ◽  
Author(s):  
Guo Dong ◽  
Jiangbo Yu ◽  
Gaojun Shan ◽  
Lide Su ◽  
Nannan Yu ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Chorioallantoic Membrane ◽  
Tube Formation ◽  
Luciferase Reporter ◽  
Dependent Manner ◽  
Stat3 Pathway ◽  
Protein Levels ◽  
Chick Chorioallantoic Membrane

Atherosclerosis (AS) is a life-threatening vascular disease. RNA N6-methyladenosine (m6A) modification level is dysregulated in multiple pathophysiologic processes including AS. In this text, the roles and molecular mechanisms of m6A writer METTL3 in AS progression were explored in vitro and in vivo. In the present study, cell proliferative, migratory, and tube formation capacities were assessed through CCK-8, Transwell migration, and tube formation assays, respectively. RNA m6A level was examined through a commercial kit. RNA and protein levels of genes were measured through RT-qPCR and western blot assays, respectively. VEGF secretion level was tested through ELISA assay. JAK2 mRNA stability was detected through actinomycin D assay. The relationship of METTL3, IGF2BP1, and JAK2 was investigated through bioinformatics analysis, MeRIP, RIP, RNA pull-down, and luciferase reporter assays. An AS mouse model was established to examine the effect of METTL3 knockdown on AS development in vivo. The angiogenetic activity was examined through chick chorioallantoic membrane assay in vivo. The results showed that METTL3 was highly expressed in ox-LDL-induced dysregulated HUVECs. METTL3 knockdown inhibited cell proliferation, migration, tube formation, and VEGF expression/secretion in ox-LDL-treated HUVECs, hampered AS process in vivo, and prevented in vivo angiogenesis of developing embryos. METTL3 positively regulated JAK2 expression and JAK2/STAT3 pathway in an m6A dependent manner in HUVECs. IGF2BP1 positively regulated JAK2 expression through directly binding to an m6A site within JAK2 mRNA in HUVECs. METTL3 knockdown weakened the interaction of JAK2 and IGF2BP1. METTL3 exerted its functions through JAK2/STAT3 pathway. In conclusion, METTL3 knockdown prevented AS progression by inhibiting JAK2/STAT3 pathway via IGF2BP1.

scholarly journals Of numbers and movement – understanding transcription factor pathogenesis by advanced microscopy

2020 ◽  
Vol 13 (12) ◽  
pp. dmm046516
Author(s):  
Julia M. T. Auer ◽  
Jack J. Stoddart ◽  
Ioannis Christodoulou ◽  
Ana Lima ◽  
Kassiani Skouloudaki ◽  
...  
Keyword(s):  
Gene Expression ◽  
Single Molecule ◽  
Molecular Mechanisms ◽  
Gene Dosage ◽  
Super Resolution ◽  
Loss Of Function ◽  
Developmental Defects ◽  
Tf Gene

ABSTRACTTranscription factors (TFs) are life-sustaining and, therefore, the subject of intensive research. By regulating gene expression, TFs control a plethora of developmental and physiological processes, and their abnormal function commonly leads to various developmental defects and diseases in humans. Normal TF function often depends on gene dosage, which can be altered by copy-number variation or loss-of-function mutations. This explains why TF haploinsufficiency (HI) can lead to disease. Since aberrant TF numbers frequently result in pathogenic abnormalities of gene expression, quantitative analyses of TFs are a priority in the field. In vitro single-molecule methodologies have significantly aided the identification of links between TF gene dosage and transcriptional outcomes. Additionally, advances in quantitative microscopy have contributed mechanistic insights into normal and aberrant TF function. However, to understand TF biology, TF-chromatin interactions must be characterised in vivo, in a tissue-specific manner and in the context of both normal and altered TF numbers. Here, we summarise the advanced microscopy methodologies most frequently used to link TF abundance to function and dissect the molecular mechanisms underlying TF HIs. Increased application of advanced single-molecule and super-resolution microscopy modalities will improve our understanding of how TF HIs drive disease.

scholarly journals Circular RNA mmu_circ_0005019 inhibits fibrosis of cardiac fibroblasts and reverses electrical remodeling of cardiomyocytes

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Na Wu ◽  
Chengying Li ◽  
Bin Xu ◽  
Ying Xiang ◽  
Xiaoyue Jia ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Cardiac Fibroblasts ◽  
Circular Rna ◽  
Protective Role ◽  
Luciferase Reporter ◽  
Loss Of Function ◽  
Candidate Target ◽  
Paired Control ◽  
Reporter Assays ◽  
And Migration

Abstract Background Circular RNA (circRNA) have been reported to play important roles in cardiovascular diseases including myocardial infarction and heart failure. However, the role of circRNA in atrial fibrillation (AF) has rarely been investigated. We recently found a circRNA hsa_circ_0099734 was significantly differentially expressed in the AF patients atrial tissues compared to paired control. We aim to investigate the functional role and molecular mechanisms of mmu_circ_0005019 which is the homologous circRNA in mice of hsa_circ_0099734 in AF. Methods In order to investigate the effect of mmu_circ_0005019 on the proliferation, migration, differentiation into myofibroblasts and expression of collagen of cardiac fibroblasts, and the effect of mmu_circ_0005019 on the apoptosis and expression of Ito, INA and SK3 of cardiomyocytes, gain- and loss-of-function of cell models were established in mice cardiac fibroblasts and HL-1 atrial myocytes. Dual-luciferase reporter assays and RIP were performed to verify the binding effects between mmu_circ_0005019 and its target microRNA (miRNA). Results In cardiac fibroblasts, mmu_circ_0005019 showed inhibitory effects on cell proliferation and migration. In cardiomyocytes, overexpression of mmu_circ_0005019 promoted Kcnd1, Scn5a and Kcnn3 expression. Knockdown of mmu_circ_0005019 inhibited the expression of Kcnd1, Kcnd3, Scn5a and Kcnn3. Mechanistically, mmu_circ_0005019 exerted biological functions by acting as a miR-499-5p sponge to regulate the expression of its target gene Kcnn3. Conclusions Our findings highlight mmu_circ_0005019 played a protective role in AF development and might serve as an attractive candidate target for AF treatment.

scholarly journals TRIM27 interacts with Iκbα to promote the growth of human renal cancer cells through regulating the NF-κB pathway

BMC Cancer ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Chengwu Xiao ◽  
Wei Zhang ◽  
Meimian Hua ◽  
Huan Chen ◽  
Bin Yang ◽  
...  
Keyword(s):  
Cell Lines ◽  
Prognostic Indicator ◽  
The Cancer Genome Atlas ◽  
Mrna Levels ◽  
Loss Of Function ◽  
Protein Levels ◽  
Kaplan Meier ◽  
Cancer Genome Atlas

Abstract Background The tripartite motif (TRIM) family proteins exhibit oncogenic roles in various cancers. The roles of TRIM27, a member of the TRIM super family, in renal cell carcinoma (RCC) remained unexplored. In the current study, we aimed to investigate the clinical impact and roles of TRIM27 in the development of RCC. Methods The mRNA levels of TRIM27 and Kaplan–Meier survival of RCC were analyzed from The Cancer Genome Atlas database. Real-time PCR and Western blotting were used to measure the mRNA and protein levels of TRIM27 both in vivo and in vitro. siRNA and TRIM27 were exogenously overexpressed in RCC cell lines to manipulate TRIM27 expression. Results We discovered that TRIM27 was elevated in RCC patients, and the expression of TRIM27 was closely correlated with poor prognosis. The loss of function and gain of function results illustrated that TRIM27 promotes cell proliferation and inhibits apoptosis in RCC cell lines. Furthermore, TRIM27 expression was positively associated with NF-κB expression in patients with RCC. Blocking the activity of NF-κB attenuated the TRIM27-mediated enhancement of proliferation and inhibition of apoptosis. TRIM27 directly interacted with Iκbα, an inhibitor of NF-κB, to promote its ubiquitination, and the inhibitory effects of TRIM27 on Iκbα led to NF-κB activation. Conclusions Our results suggest that TRIM27 exhibits an oncogenic role in RCC by regulating NF-κB signaling. TRIM27 serves as a specific prognostic indicator for RCC, and strategies targeting the suppression of TRIM27 function may shed light on future therapeutic approaches.

scholarly journals Long noncoding RNA SNHG14 promotes hepatocellular carcinoma progression by regulating miR-876-5p/SSR2 axis

2021 ◽  
Vol 40 (1) ◽  
Author(s):  
Zhibin Liao ◽  
Hongwei Zhang ◽  
Chen Su ◽  
Furong Liu ◽  
Yachong Liu ◽  
...  
Keyword(s):  
Noncoding Rna ◽  
Animal Experiments ◽  
Luciferase Reporter ◽  
Western Blot Assay ◽  
Downstream Target ◽  
Protein Levels ◽  
Elevated Expression ◽  
Rna Immunoprecipitation

Abstract Background Aberrant expressions of long noncoding RNAs (lncRNAs) have been demonstrated to be related to the progress of HCC. The mechanisms that SNHG14 has participated in the development of HCC are obscure. Methods Quantitative real-time PCR (qRT-PCR) was used to measure the lncRNA, microRNA and mRNA expression level. Cell migration, invasion and proliferation ability were evaluated by transwell and CCK8 assays. The ceRNA regulatory mechanism of SNHG14 was evaluated by RNA immunoprecipitation (RIP) and dual luciferase reporter assay. Tumorigenesis mouse model was used to explore the roles of miR-876-5p in vivo. The protein levels of SSR2 were measured by western blot assay. Results In this study, we demonstrated that SNHG14 was highly expressed in HCC tissues, meanwhile, the elevated expression of SNHG14 predicted poor prognosis in patients with HCC. SNHG14 promoted proliferation and metastasis of HCC cells. We further revealed that SNHG14 functioned as a competing endogenous RNA (ceRNA) for miR-876-5p and that SSR2 was a downstream target of miR-876-5p in HCC. Transwell, CCK8 and animal experiments exhibited miR-876-5p inhibited HCC progression in vitro and in vivo. By conducting rescue experiments, we found the overexpression of SSR2 or knocking down the level of miR-876-5p could reverse the suppressive roles of SNHG14 depletion in HCC. Conclusion SNHG14 promotes HCC progress by acting as a sponge of miR-876-5p to regulate the expression of SSR2 in HCC.

scholarly journals Cell–cell coupling and DNA methylation abnormal phenotypes in the after-hours mice

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Federico Tinarelli ◽  
Elena Ivanova ◽  
Ilaria Colombi ◽  
Erica Barini ◽  
Edoardo Balzani ◽  
...  
Keyword(s):  
Gene Expression ◽  
Dna Methylation ◽  
Neuronal Networks ◽  
Molecular Mechanisms ◽  
Ex Vivo ◽  
Neuronal Cultures ◽  
Functional Impairments ◽  
After Hours ◽  
The Impact

Abstract Background DNA methylation has emerged as an important epigenetic regulator of brain processes, including circadian rhythms. However, how DNA methylation intervenes between environmental signals, such as light entrainment, and the transcriptional and translational molecular mechanisms of the cellular clock is currently unknown. Here, we studied the after-hours mice, which have a point mutation in the Fbxl3 gene and a lengthened circadian period. Methods In this study, we used a combination of in vivo, ex vivo and in vitro approaches. We measured retinal responses in Afh animals and we have run reduced representation bisulphite sequencing (RRBS), pyrosequencing and gene expression analysis in a variety of brain tissues ex vivo. In vitro, we used primary neuronal cultures combined to micro electrode array (MEA) technology and gene expression. Results We observed functional impairments in mutant neuronal networks, and a reduction in the retinal responses to light-dependent stimuli. We detected abnormalities in the expression of photoreceptive melanopsin (OPN4). Furthermore, we identified alterations in the DNA methylation pathways throughout the retinohypothalamic tract terminals and links between the transcription factor Rev-Erbα and Fbxl3. Conclusions The results of this study, primarily represent a contribution towards an understanding of electrophysiological and molecular phenotypic responses to external stimuli in the Afh model. Moreover, as DNA methylation has recently emerged as a new regulator of neuronal networks with important consequences for circadian behaviour, we discuss the impact of the Afh mutation on the epigenetic landscape of circadian biology.

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