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1.
Biomedicines ; 12(5)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38790894

RESUMO

Long noncoding RNAs (lncRNAs) are RNA molecules of 200 nucleotides or more in length that are not translated into proteins. Their expression is tissue-specific, with the vast majority involved in the regulation of cellular processes and functions. Many human diseases, including cancer, have been shown to be associated with deregulated lncRNAs, rendering them potential therapeutic targets and biomarkers for differential diagnosis. The expression of lncRNAs in the nervous system varies in different cell types, implicated in mechanisms of neurons and glia, with effects on the development and functioning of the brain. Reports have also shown a link between changes in lncRNA molecules and the etiopathogenesis of brain neoplasia, including glioblastoma multiforme (GBM). GBM is an aggressive variant of brain cancer with an unfavourable prognosis and a median survival of 14-16 months. It is considered a brain-specific disease with the highly invasive malignant cells spreading throughout the neural tissue, impeding the complete resection, and leading to post-surgery recurrences, which are the prime cause of mortality. The early diagnosis of GBM could improve the treatment and extend survival, with the lncRNA profiling of biological fluids promising the detection of neoplastic changes at their initial stages and more effective therapeutic interventions. This review presents a systematic overview of GBM-associated deregulation of lncRNAs with a focus on lncRNA fingerprints in patients' blood.

2.
Pharmaceutics ; 16(1)2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38258133

RESUMO

The heterogeneity of the glioma subtype glioblastoma multiforme (GBM) challenges effective neuropathological treatment. The reliance on in vitro studies and xenografted animal models to simulate human GBM has proven ineffective. Currently, a dearth of knowledge exists regarding the applicability of cell line biomolecules to the realm of GBM pathogenesis. Our study's objectives were to address this preclinical issue and assess prominin-1, ICAM-1, PARTICLE and GAS5 as potential GBM diagnostic targets. The methodologies included haemoxylin and eosin staining, immunofluorescence, in situ hybridization and quantitative PCR. The findings identified that morphology correlates with malignancy in GBM patient pathology. Immunofluorescence confocal microscopy revealed prominin-1 in pseudo-palisades adjacent to necrotic foci in both animal and human GBM. Evidence is presented for an ICAM-1 association with degenerating vasculature. Significantly elevated nuclear PARTICLE expression from in situ hybridization and quantitative PCR reflected its role as a tumor activator. GAS5 identified within necrotic GBM validated this potential prognostic biomolecule with extended survival. Here we present evidence for the stem cell marker prominin-1 and the chemotherapeutic target ICAM-1 in a glioma animal model and GBM pathology sections from patients that elicited alternative responses to adjuvant chemotherapy. This foremost study introduces the long non-coding RNA PARTICLE into the context of human GBM pathogenesis while substantiating the role of GAS5 as a tumor suppressor. The validation of GBM biomarkers from cellular models contributes to the advancement towards superior detection, therapeutic responders and the ultimate attainment of promising prognoses for this currently incurable brain cancer.

3.
Front Neurol ; 13: 954712, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36388199

RESUMO

Introduction: While the role of physiotherapy as part of a comprehensive inpatient rehabilitation is indisputable, clear evidence concerning the effectiveness of different rehabilitation managements [interdisciplinary implementing the International Classification of Functioning, disability and health (ICF) vs. multidisciplinary model] and physiotherapy categories (neuroproprioceptive "facilitation, inhibition" vs. motor/skill acquisitions using technologies) are still lacking. In this study, four kinds of comprehensive inpatient rehabilitation with different management and content of physical therapy will be compared. Moreover, focus will be placed on the identification of novel biological molecules reflective of effective rehabilitation. Long non-coding RNAs (lncRNAs) are transcripts (>200 bps) of limited coding potential, which have recently been recognized as key factors in neuronal signaling pathways in ischemic stroke and as such, may provide a valuable readout of patient recovery and neuroprotection during therapeutic progression. Methods and analysis: Adults after the first ischemic stroke in an early sub-acute phase with motor disability will be randomly assigned to one of four groups and undergo a 3 weeks comprehensive inpatient rehabilitation of different types: interdisciplinary team work using ICF model as a guide; multidisciplinary teamwork implementing neuroproprioceptive "facilitation and inhibition" physiotherapy; multidisciplinary teamwork implementing technology-based physiotherapy; and standard multidisciplinary teamwork. Primary (the Goal Attainment Scale, the Patient-Reported Outcomes Measurement Information System, and the World Health Organization Disability Assessment Schedule) and secondary (motor, cognitive, psychological, speech and swallowing functions, functional independence) outcomes will be measured. A blood sample will be obtained upon consent (20 mls; representing pre-rehabilitation molecular) before and after the inpatient program. Primary outcomes will be followed up again 3 and 12 months after the end of the program. The overarching aim of this study is to determine the effectiveness of various rehabilitation managements and physiotherapeutic categories implemented by patients post ischemic stroke via analysis of primary, secondary and long non-coding RNA readouts. This clinical trial will offer an innovative approach not previously tested and will provide new complex analysis along with public assessable molecular biological evidence of various rehabilitation methodology for the alleviation of the effects of ischemic stroke. Clinical trial registration: NCT05323916, https://clinicaltrials.gov/ct2/show/NCT05323916.

4.
Biomedicines ; 10(11)2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36428462

RESUMO

Adaptive immunity changes over an individual's lifetime, maturing by adulthood and diminishing with old age. Epigenetic mechanisms involving DNA and histone methylation form the molecular basis of immunological memory during lymphocyte development. Monocytes alter their function to convey immune tolerance, yet the epigenetic influences at play remain to be fully understood in the context of lifespan. This study of a healthy genetically homogenous cohort of children, adults and seniors sought to decipher the epigenetic dynamics in B-lymphocytes and monocytes. Variable global cytosine methylation within retro-transposable LINE-1 repeats was noted in monocytes compared to B-lymphocytes across age groups. The expression of the human leukocyte antigen (HLA)-DQ alpha chain gene HLA-DQA1*01 revealed significantly reduced levels in monocytes in all ages relative to B-lymphocytes, as well as between lifespan groups. High melting point analysis and bisulfite sequencing of the HLA-DQA1*01 promoter in monocytes highlighted variable cytosine methylation in children and seniors but greater stability at this locus in adults. Further epigenetic evaluation revealed higher histone lysine 27 trimethylation in monocytes from this adult group. Chromatin immunoprecipitation and RNA pulldown demonstrated association with a novel lncRNA TINA with structurally conserved similarities to the previously recognized epigenetic modifier PARTICLE. Seeking to interpret the epigenetic immunological landscape across three representative age groups, this study focused on HLA-DQA1*01 to expose cytosine and histone methylation alterations and their association with the non-coding transcriptome. Such insights unveil previously unknown complex epigenetic layers, orchestrating the strength and weakening of adaptive immunity with the progression of life.

5.
Int J Mol Sci ; 23(11)2022 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-35682780

RESUMO

Celiac disease (CeD) manifests with autoimmune intestinal inflammation from gluten and genetic predisposition linked to human leukocyte antigen class-II (HLA-II) gene variants. Antigen-presenting cells facilitate gluten exposition through the interaction of their surface major histocompatibility complex (MHC) with the T cell receptor (TCR) on T lymphocytes. This fundamental mechanism of adaptive immunity has broadened upon recognition of extracellular exosomal MHC, raising awareness of an alternative means for antigen presentation. This study demonstrates that conditioned growth media (CGM) previously exposed to monocyte-derived dendritic cells from CeD significantly downregulates the CD3+ lineage marker of control T cells. Such increased activation was reflected in their elevated IL-2 secretion. Exosome localization motif identification and quantification within HLA-DQA1 and HLA-DQB1 transcripts highlighted their significant prevalence within HLA-DQB1 alleles associated with CeD susceptibility. Flow cytometry revealed the strong correlation between HLA-DQ and the CD63 exosomal marker in T cells exposed to CGM from MoDCs sourced from CeD patients. This resulted in lower concentrations of CD25+ CD127- T cells, suggestive of their compromised induction to T-regulatory cells associated with CeD homeostasis. This foremost comparative study deciphered the genomic basis and extracellular exosomal effects of HLA transfer on T lymphocytes in the context of CeD, offering greater insight into this auto-immune disease.


Assuntos
Doença Celíaca , Alelos , Glutens/genética , Antígenos HLA-DQ/genética , Humanos , Linfócitos T Reguladores
6.
Autism Res ; 15(5): 791-805, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35178882

RESUMO

The cerebellum hosts more than half of all neurons of the human brain, with their organized activity playing a key role in coordinating motor functions. Cerebellar activity has also been implicated in the control of speech, communication, and social behavior, which are compromised in autism spectrum disorders (ASD). Despite major research advances, there is a shortage of mechanistic data relating cellular and molecular changes in the cerebellum to autistic behavior. We studied the impact of tuberous sclerosis complex 2 haploinsufficiency (Tsc2+/-) with downstream mTORC1 hyperactivity on cerebellar morphology and cellular organization in 1, 9, and 18 m.o. Eker rats, to determine possible structural correlates of an autism-like behavioural phenotype in this model. We report a greater developmental expansion of the cerebellar vermis, owing to enlarged white matter and thickened molecular layer. Histochemical and immunofluorescence data suggest age-related demyelination of central tract of the vermis, as evident from reduced level of myelin-basic protein in the arbora vitae. We also observed a higher number of astrocytes in Tsc2+/- rats of older age while the number of Purkinje cells (PCs) in these animals was lower than in wild-type controls. Unlike astrocytes and PCs, Bergmann glia remained unaltered at all ages in both genotypes, while the number of microglia was higher in Tsc2+/- rats of older age. The convergent evidence for a variety of age-dependent cellular changes in the cerebellum of rats associated with mTORC1 hyperactivity, thus, predicts an array of functional impairments, which may contribute to the developmental onset of an autism-like behavioral phenotype in this model. LAY SUMMARY: This study elucidates the impact of constitutive mTORC1 hyperactivity on cerebellar morphology and cellular organization in a rat model of autism and epilepsy. It describes age-dependent degeneration of Purkinje neurons, with demyelination of central tract as well as activation of microglia, and discusses the implications of these changes for neuro-behavioral phenotypes. The described changes provide new indications for the putative mechanisms underlying cerebellar impairments with their age-related onset, which may contribute to the pathobiology of autism, epilepsy, and related disorders.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Doenças Desmielinizantes , Epilepsia , Animais , Cerebelo/metabolismo , Doenças Desmielinizantes/complicações , Doenças Desmielinizantes/metabolismo , Epilepsia/complicações , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Fenótipo , Ratos , Esclerose Tuberosa
7.
Int J Mol Sci ; 22(18)2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34576145

RESUMO

The autoimmune condition, Celiac Disease (CeD), displays broad clinical symptoms due to gluten exposure. Its genetic association with DQ variants in the human leukocyte antigen (HLA) system has been recognised. Monocyte-derived mature dendritic cells (MoDCs) present gluten peptides through HLA-DQ and co-stimulatory molecules to T lymphocytes, eliciting a cytokine-rich microenvironment. Having access to CeD associated families prevalent in the Czech Republic, this study utilised an in vitro model to investigate their differential monocyte profile. The higher monocyte yields isolated from PBMCs of CeD patients versus control individuals also reflected the greater proportion of dendritic cells derived from these sources following lipopolysaccharide (LPS)/ peptic-tryptic-gliadin (PTG) fragment stimulation. Cell surface markers of CeD monocytes and MoDCs were subsequently profiled. This foremost study identified a novel bio-profile characterised by elevated CD64 and reduced CD33 levels, unique to CD14++ monocytes of CeD patients. Normalisation to LPS stimulation revealed the increased sensitivity of CeD-MoDCs to PTG, as shown by CD86 and HLA-DQ flow cytometric readouts. Enhanced CD86 and HLA-DQ expression in CeD-MoDCs were revealed by confocal microscopy. Analysis highlighted their dominance at the CeD-MoDC membrane in comparison to controls, reflective of superior antigen presentation ability. In conclusion, this investigative study deciphered the monocytes and MoDCs of CeD patients with the identification of a novel bio-profile marker of potential diagnostic value for clinical interpretation. Herein, the characterisation of CD86 and HLA-DQ as activators to stimulants, along with robust membrane assembly reflective of efficient antigen presentation, offers CeD targeted therapeutic avenues worth further exploration.


Assuntos
Apresentação de Antígeno/imunologia , Doença Celíaca/imunologia , Células Dendríticas/imunologia , Gliadina/efeitos adversos , Adolescente , Adulto , Idoso , Antígenos CD/metabolismo , Doenças Autoimunes/imunologia , Biomarcadores/metabolismo , Doença Celíaca/epidemiologia , Membrana Celular/metabolismo , República Tcheca/epidemiologia , Suscetibilidade a Doenças , Família , Feminino , Antígenos HLA-DQ/metabolismo , Humanos , Lipopolissacarídeos , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Linhagem , Linfócitos T Citotóxicos/imunologia , Adulto Jovem
8.
Brain Sci ; 11(6)2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34207434

RESUMO

Glioblastoma multiforme (GBM) is a primary brain cancer of poor prognosis, with existing treatments remaining essentially palliative. Current GBM therapy fails due to rapid reappearance of the heterogeneous neoplasm, with models suggesting that the recurrent growth is from treatment-resistant glioblastoma stem-like cells (GSCs). Whether GSCs depend on survival/proliferative cues from their surrounding microenvironmental niche, particularly surrounding the leading edge after treatment remains unknown. Simulating human GBM in the laboratory relies on representative cell lines and xenograft models for translational medicine. Due to U87MG source discrepancy and differential proliferation responses to retinoic acid treatment, this study highlights the challenges faced by laboratory scientists working with this representative GBM cell line. Investigating the response to all trans-retinoic acid (ATRA) revealed its sequestering of the prominin-1 stem cell marker. ICAM-1 universally present throughout U87MG was enhanced by ATRA, of interest for chemotherapy targeting studies. ATRA triggered diverse expression patterns of long non-coding RNAs PARTICLE and GAS5 in the leading edge and established monolayer growth zone microenvironment. Karyotyping confirmed the female origin of U87MG sourced from Europe. Passaging U87MG revealed the presence of chromosomal anomalies reflective of structural genomic alterations in this glioblastoma cell line. All evidence considered, this study exposes further phenotypic nuances of U87MG which may belie researchers seeking data contributing towards the elusive cure for GBM.

10.
Int J Mol Sci ; 22(1)2020 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-33396557

RESUMO

An enigmatic localized pneumonia escalated into a worldwide COVID-19 pandemic from Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). This review aims to consolidate the extensive biological minutiae of SARS-CoV-2 which requires decipherment. Having one of the largest RNA viral genomes, the single strand contains the genes ORF1ab, S, E, M, N and ten open reading frames. Highlighting unique features such as stem-loop formation, slippery frameshifting sequences and ribosomal mimicry, SARS-CoV-2 represents a formidable cellular invader. Hijacking the hosts translational engine, it produces two polyprotein repositories (pp1a and pp1ab), armed with self-cleavage capacity for production of sixteen non-structural proteins. Novel glycosylation sites on the spike trimer reveal unique SARS-CoV-2 features for shielding and cellular internalization. Affording complexity for superior fitness and camouflage, SARS-CoV-2 challenges diagnosis and vaccine vigilance. This review serves the scientific community seeking in-depth molecular details when designing drugs to curb transmission of this biological armament.


Assuntos
COVID-19/virologia , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Proteínas Virais/metabolismo , COVID-19/genética , COVID-19/metabolismo , Humanos , Fases de Leitura Aberta , Pandemias , Filogenia , RNA Viral/genética
11.
Neurotherapeutics ; 15(4): 1032-1035, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30242774

RESUMO

While the extensive hunt for therapeutics combating Alzheimer's disease (AD) has fallen short of delivering effective treatments, breakthroughs towards understanding the disease mechanisms and identifying areas for future research have nevertheless been enabled. The majority of clinical trials with ß- and γ-secretase modulators have been suspended from additional studies or terminated due to toxicity issues and health concerns. The lack of progress in developing innovative AD therapies has also prompted a resurgence of interest in more traditional symptomatic treatments with cholinesterase inhibitors and N-methyl-D-aspartate receptor antagonists, as well as in the research of immune response modulators. Recently, evidence has emerged showing that inhibitors of arginine metabolism and in particular blockers of arginase, an enzyme that catalyzes the breakdown of L-arginine, could present an effective therapeutic candidate for halting the progression of AD and boosting cognition and memory. In this commentary, we present a brief overview of reports on arginase inhibitors in AD mouse models and discuss emerging advantages and areas for careful consideration on the road to clinical translation.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Arginase/antagonistas & inibidores , Arginase/metabolismo , Inibidores Enzimáticos/uso terapêutico , Humanos
12.
Oncotarget ; 8(50): 87431-87441, 2017 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-29152092

RESUMO

Breakage of the fragile site FRA16D disrupts the WWOX (WW Domain Containing Oxidoreductase) tumor suppressor gene in osteosarcoma. However, the frequency of breakage is not sufficient to explain the rate of WWOX loss in pathogenesis. The involvement of non-coding RNA transcripts is proposed due to their accumulation at fragile sites, where they are advocated to influence specific chromosomal regions associated with malignancy. The long ncRNA PARTICLE (promoter of MAT2A antisense radiation-induced circulating long non-coding RNA) is transiently elevated in response to irradiation and influences epigenetic silencing modification within WWOX. It now emerges that elevated PARTICLE levels are significantly associated with FRA16D non-breakage in OS patients. Although not associated with overall survival, high PARTICLE levels were found to be significantly linked to metastasis free outcome. The transcription of both PARTICLE and WWOX are transiently responsive to exposure to low doses of radiation in osteosarcoma cell lines. Herein, a relationship between WWOX and PARTICLE transcription is suggested in human osteosarcoma cell lines representing alternative genetic backgrounds. PARTICLE over-expression ameliorated WWOX promoter activity in U2OS harboring FRA16D non-breakage. It can be concluded that the lncRNA PARTICLE influences the WWOX tumor suppressor and in the absence of WWOX FRA16D breakage, it is associated with OS metastasis-free survival.

13.
Oncotarget ; 8(45): 78397-78409, 2017 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-29108237

RESUMO

Generated by Quaking (QKI), circular RNAs (circRNAs) are newly recognised non-coding RNA (ncRNA) members characterised by tissue specificity, increased stability and enrichment within exosomes. Studies have shown that ionizing radiation (IR) can influence ncRNA transcription. However, it is unknown whether circRNAs or indeed QKI are regulated by IR. Microarray circRNA profiling and next generation sequencing revealed that circRNA expression was altered by low and medium dose exposure sourced predominantly from genes influencing the p53 pathway. CircRNAs KIRKOS-71 and KIRKOS-73 transcribed from the WWOX (WW Domain Containing Oxidoreductase) tumor suppressor (a p53 regulator) responded within hours to IR. KIRKOS-71 and KIRKOS-73 were present in exosomes yet exhibited differential transcript clearance between irradiated cell lines. Dual-quasar labelled probes and in-situ hybridization demonstrated the intercellular distribution of KIRKOS-71 and KIRKOS-73 predominantly within the perinucleus. QKI knockdown removed nuclear expression of these circRNAs with no significant effect on cytosolic KIRKOS-71 and KIRKOS-73. Distinct QKI transcription between cell lines and its augmented interaction with KIRKOS-71 and KIRKOS-73 was noted post IR. This foremost study provides evidence that QKI and circRNAs partake in the cellular irradiation response. KIRKOS-71 and KIRKOS-73 as stable secreted circRNAs may afford vital characteristics worth syphoning as promising diagnostic radiotherapy biomarkers.

14.
Sci Rep ; 7(1): 7163, 2017 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-28769061

RESUMO

The long non-coding RNA PARTICLE (Gene PARTICL- 'Promoter of MAT2A-Antisense RadiaTion Induced Circulating LncRNA) partakes in triple helix (triplex) formation, is transiently elevated following low dose irradiation and regulates transcription of its neighbouring gene - Methionine adenosyltransferase 2A. It now emerges that PARTICLE triplex sites are predicted in many different genes across all human chromosomes. In silico analysis identified additional regions for PARTICLE triplexes at >1600 genomic locations. Multiple PARTICLE triplexes are clustered predominantly within the human and mouse tumor suppressor WW Domain Containing Oxidoreductase (WWOX) gene. Surface plasmon resonance diffraction and electrophoretic mobility shift assays were consistent with PARTICLE triplex formation within human WWOX with high resolution imaging demonstrating its enrichment at this locus on chromosome 16. PARTICLE knockdown and over-expression resulted in inverse changes in WWOX transcripts levels with siRNA interference eliminating PARTICLEs elevated transcription to irradiation. The evidence for a second functional site of PARTICLE triplex formation at WWOX suggests that PARTICLE may form triplex-mediated interactions at multiple positions in the human genome including remote loci. These findings provide a mechanistic explanation for the ability of lncRNAs to regulate the expression of numerous genes distributed across the genome.


Assuntos
Genoma Humano , RNA Longo não Codificante/química , RNA Longo não Codificante/genética , Proteínas Supressoras de Tumor/genética , Oxidorredutase com Domínios WW/genética , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Sobrevivência Celular , Cromossomos Humanos Par 16 , Suscetibilidade a Doenças , Epistasia Genética , Regulação da Expressão Gênica , Loci Gênicos , Genoma , Humanos , Sistema de Sinalização das MAP Quinases , Camundongos , Conformação de Ácido Nucleico , Regiões Promotoras Genéticas , Ligação Proteica , Interferência de RNA , RNA Interferente Pequeno/genética , Transcrição Gênica
15.
Sci Rep ; 7(1): 1790, 2017 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-28496150

RESUMO

PARTICLE (Gene PARTICL- 'Promoter of MAT2A-Antisense RadiaTion Induced Circulating LncRNA) expression is transiently elevated following low dose irradiation typically encountered in the workplace and from natural sources. This long non-coding RNA recruits epigenetic silencers for cis-acting repression of its neighbouring Methionine adenosyltransferase 2A gene. It now emerges that PARTICLE operates as a trans-acting mediator of DNA and histone lysine methylation. Chromatin immunoprecipitation sequencing (ChIP-seq) and immunological evidence established elevated PARTICLE expression linked to increased histone 3 lysine 27 trimethylation. Live-imaging of dbroccoli-PARTICLE revealing its dynamic association with DNA methyltransferase 1 was confirmed by flow cytometry, immunoprecipitation and direct competitive binding interaction through electrophoretic mobility shift assay. Acting as a regulatory docking platform, the long non-coding RNA PARTICLE serves to interlink epigenetic modification machineries and represents a compelling innovative component necessary for gene silencing on a global scale.


Assuntos
Metilação de DNA , Histonas/metabolismo , RNA Longo não Codificante/genética , Linhagem Celular Tumoral , Ilhas de CpG , DNA (Citosina-5-)-Metiltransferase 1/genética , Metilação de DNA/efeitos da radiação , Epistasia Genética , Perfilação da Expressão Gênica , Genoma Humano , Humanos , Metilação , Radiação Ionizante , Proteínas Supressoras de Tumor/genética , Oxidorredutase com Domínios WW/genética
16.
Cell Rep ; 11(3): 474-85, 2015 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-25900080

RESUMO

Exposure to low-dose irradiation causes transiently elevated expression of the long ncRNA PARTICLE (gene PARTICLE, promoter of MAT2A-antisense radiation-induced circulating lncRNA). PARTICLE affords both a cytosolic scaffold for the tumor suppressor methionine adenosyltransferase (MAT2A) and a nuclear genetic platform for transcriptional repression. In situ hybridization discloses that PARTICLE and MAT2A associate together following irradiation. Bromouridine tracing and presence in exosomes indicate intercellular transport, and this is supported by ex vivo data from radiotherapy-treated patients. Surface plasmon resonance indicates that PARTICLE forms a DNA-lncRNA triplex upstream of a MAT2A promoter CpG island. We show that PARTICLE represses MAT2A via methylation and demonstrate that the radiation-induced PARTICLE interacts with the transcription-repressive complex proteins G9a and SUZ12 (subunit of PRC2). The interplay of PARTICLE with MAT2A implicates this lncRNA in intercellular communication and as a recruitment platform for gene-silencing machineries through triplex formation in response to irradiation.


Assuntos
Metilação de DNA/efeitos da radiação , Regulação da Expressão Gênica/efeitos da radiação , RNA Longo não Codificante/biossíntese , RNA Longo não Codificante/genética , Carcinoma de Células Escamosas/radioterapia , Linhagem Celular , Imunoprecipitação da Cromatina , Metilação de DNA/genética , Ensaio de Desvio de Mobilidade Eletroforética , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Immunoblotting , Hibridização In Situ , Metionina Adenosiltransferase/biossíntese , Metionina Adenosiltransferase/genética , Análise de Sequência com Séries de Oligonucleotídeos , Radiação Ionizante , Carcinoma de Células Escamosas de Cabeça e Pescoço , Ressonância de Plasmônio de Superfície
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