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1.
Gene ; 723: 144126, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31589963

RESUMO

Non-coding RNAs are known to participate in cancer initiation, progression, and metastasis by regulating the status of chromatin epigenetics and gene expression. Although these non-coding RNAs do not possess defined protein-coding potential, they are involved in the expression and stability of messenger RNA (mRNA). The length of microRNAs (miRs) ranges between 20 and 22 nt, whereas, long non-coding RNAs (lncRNAs) length ranges between 200 nt to 1 Kb. In the case of circular RNAs (circRNAs), the size varies depending upon the length of the exon from where they were derived. Epigenetic regulations of miR and lncRNA genes will influence the gene expression by modulating histone acetylation and methylation patterns. Especially, lncRNAs will act as a scaffold for various epigenetic proteins, such as EZH2 and LSD1, and influence the chromatin epigenetic state at various genomic loci involved at silencing. Thus investigations on the expression of lncRNAs and designing drugs to modulate the expression of these genes will have a profound impact on future therapeutics against cancers such as Glioblastoma Multiforme (GBM) and also against various other diseases. With the recent advancements in genome-wide transcriptomic studies, scientists are focused on the non-coding RNAs and their regulations on various cellular processes involved in GBM and on other types of cancer as well as trying to understand possible epigenetic modulations that help in generating promising therapeutics for the future generations. In this review, the involvement of epigenetic proteins, enzymes that change chromatin architecture and epigenetic landscape and new roles of lncRNAs that are involved in GBM progression are elaborately discussed.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , MicroRNAs/genética , RNA Longo não Codificante/genética , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/genética , Ensaios Clínicos como Assunto , Epigênese Genética/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Redes Reguladoras de Genes/efeitos dos fármacos , Glioblastoma/genética , Humanos
2.
Anticancer Res ; 39(10): 5473-5481, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31570441

RESUMO

BACKGROUND/AIM: Aerial parts and seeds of the neem tree (Azadirachta indica) have long been used in traditional medicine such as Ayurveda for health-related purposes. Our interest in neem bioactives lies in their potential use as standalone anticancer agents, or as adjuvants to standard therapy. The aim of the present study was to explore a supercritical CO2 extract (SCNE) of neem leaf and a prominent liminoid in neem leaf, nimbolide, for epigenetic activity. MATERIALS AND METHODS: Human colorectal cancer cell lines (HCT116 and HT29) were cultured for 48 h in the presence of neem extract or nimbolide and evaluated for growth inhibition and evidence of suppression of histone deacetylation and DNA methylation. RESULTS: Both SCNE and nimbolide suppressed the proliferation of colon cancer cells by inducing epigenetic modifications. CONCLUSION: Neem leaf contains bioactive constituents which modify epigenetic activity.


Assuntos
Azadirachta/química , Neoplasias Colorretais/tratamento farmacológico , Epigênese Genética/efeitos dos fármacos , Extratos Vegetais/farmacologia , Folhas de Planta/química , Dióxido de Carbono/química , Dióxido de Carbono/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Células HCT116 , Células HT29 , Humanos , Limoninas/farmacologia
3.
Chem Biol Interact ; 313: 108834, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31545955

RESUMO

The anthracycline doxorubicin (DOX) is widely used in cancer therapy with the limitation of cardiotoxicity leading to the development of congestive heart failure. DOX-induced oxidative stress and changes of the phosphoproteome as well as epigenome were described but the exact mechanisms of the adverse long-term effects are still elusive. Here, we tested the impact of DOX treatment on cell death, oxidative stress parameters and expression profiles of proteins involved in epigenetic pathways in a cardiomyocyte cell culture model. Markers of oxidative stress, apoptosis and expression of proteins involved in epigenetic processes were assessed by immunoblotting in cultured rat myoblasts (H9c2) upon treatment with DOX (1 or 5 µM for 24 or 48 h) in adherent viable and detached apoptotic cells. The apoptosis markers cleaved caspase-3 and fractin as well as oxidative stress markers 3-nitrotyrosine and malondialdehyde were dose-dependently increased by DOX treatment. Histone deacetylases (SIRT1 and HDAC2), histone lysine demethylases (KDM3A and LSD1) and histone lysine methyltransferases (SET7 and SMYD1) were significantly regulated by DOX treatment with generation of cleaved protein fragments and posttranslational modifications. Overall, we found significant decrease in histone 3 acetylation in DOX-treated cells. DOX treatment of cultured cardiomyocyte precursor cells causes severe cell death by apoptosis associated with cellular oxidative stress. In addition, significant regulation of proteins involved in epigenetic processes and changes in global histone 3 acetylation were observed. However, the significance and clinical impact of these changes remain elusive.


Assuntos
Doxorrubicina/efeitos adversos , Epigênese Genética/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Animais , Antibióticos Antineoplásicos/efeitos adversos , Apoptose/efeitos dos fármacos , Apoptose/genética , Biomarcadores/metabolismo , Cardiotoxicidade/metabolismo , Células Cultivadas , Relação Dose-Resposta a Droga , Histona Desacetilases/metabolismo , Histona Desmetilases/metabolismo , Histonas/metabolismo , Peróxido de Hidrogênio/farmacologia , Miócitos Cardíacos/patologia , Miócitos Cardíacos/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Ratos
4.
Toxicol Lett ; 315: 31-38, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31419471

RESUMO

Endocrine disruptor zearalenone (ZEA) has been found to damage the reproductive system especially spermatogenesis. In our previous report, we have found that low dose (lower than No-Observed Effect Level, NOEL) ZEA exposure disturbed mouse spermatogenesis and diminished mouse semen quality. The purpose of current investigation was to explore the underlying mechanisms of pubertal low dose ZEA exposure upsetting spermatogenesis. And it was demonstrated that pubertal low dose ZEA exposure disrupted the meiosis process and the important genetic pathways to inhibit the spermatogenesis and even to diminish the semen quality with the decrease in spermatozoa motility and concentration. The DNA methylation markers 5mC and 5hmC were decreased, the histone methylation marker H3K27 was increased, at the same time estrogen receptor alpha was diminished in mouse testis after pubertal low dose ZEA exposure. The data indicate that the disruption in spermatogenesis by pubertal low dose ZEA exposure may be through the alterations in genetic and epigenetic pathways, and the interactions with estrogen receptor signaling pathway. Therefore, we should pay great attention on ZEA exposure to reduce its adverse impacts on male reproductive health.


Assuntos
Divisão Celular/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Receptor alfa de Estrogênio/efeitos dos fármacos , Motilidade Espermática/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Espermatogênese/genética , Zearalenona/toxicidade , Adolescente , Animais , Modelos Animais de Doenças , Humanos , Masculino , Camundongos , Transdução de Sinais/efeitos dos fármacos
5.
Nat Commun ; 10(1): 3081, 2019 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-31300673

RESUMO

Dimethyl fumarate (DMF) is a first-line-treatment for relapsing-remitting multiple sclerosis (RRMS). The redox master regulator Nrf2, essential for redox balance, is a target of DMF, but its precise therapeutic mechanisms of action remain elusive. Here we show impact of DMF on circulating monocytes and T cells in a prospective longitudinal RRMS patient cohort. DMF increases the level of oxidized isoprostanes in peripheral blood. Other observed changes, including methylome and transcriptome profiles, occur in monocytes prior to T cells. Importantly, monocyte counts and monocytic ROS increase following DMF and distinguish patients with beneficial treatment-response from non-responders. A single nucleotide polymorphism in the ROS-generating NOX3 gene is associated with beneficial DMF treatment-response. Our data implicate monocyte-derived oxidative processes in autoimmune diseases and their treatment, and identify NOX3 genetic variant, monocyte counts and redox state as parameters potentially useful to inform clinical decisions on DMF therapy of RRMS.


Assuntos
Fumarato de Dimetilo/uso terapêutico , Imunossupressores/uso terapêutico , Monócitos/imunologia , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , NADPH Oxidases/genética , Adulto , Metilação de DNA/efeitos dos fármacos , Fumarato de Dimetilo/farmacologia , Epigênese Genética/efeitos dos fármacos , Feminino , Humanos , Imunossupressores/farmacologia , Contagem de Leucócitos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Esclerose Múltipla Recidivante-Remitente/sangue , Esclerose Múltipla Recidivante-Remitente/imunologia , NADPH Oxidases/metabolismo , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Fator 2 Relacionado a NF-E2/metabolismo , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Espécies Reativas de Oxigênio/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Resultado do Tratamento
6.
Nat Commun ; 10(1): 2723, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31222014

RESUMO

Non-genetic drug resistance is increasingly recognised in various cancers. Molecular insights into this process are lacking and it is unknown whether stable non-genetic resistance can be overcome. Using single cell RNA-sequencing of paired drug naïve and resistant AML patient samples and cellular barcoding in a unique mouse model of non-genetic resistance, here we demonstrate that transcriptional plasticity drives stable epigenetic resistance. With a CRISPR-Cas9 screen we identify regulators of enhancer function as important modulators of the resistant cell state. We show that inhibition of Lsd1 (Kdm1a) is able to overcome stable epigenetic resistance by facilitating the binding of the pioneer factor, Pu.1 and cofactor, Irf8, to nucleate new enhancers that regulate the expression of key survival genes. This enhancer switching results in the re-distribution of transcriptional co-activators, including Brd4, and provides the opportunity to disable their activity and overcome epigenetic resistance. Together these findings highlight key principles to help counteract non-genetic drug resistance.


Assuntos
Antineoplásicos/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Leucemia Mieloide Aguda/tratamento farmacológico , Transativadores/antagonistas & inibidores , Animais , Antineoplásicos/uso terapêutico , Medula Óssea/patologia , Sistemas CRISPR-Cas/genética , Linhagem Celular Tumoral , Epigênese Genética/efeitos dos fármacos , Feminino , Células HEK293 , Humanos , Estimativa de Kaplan-Meier , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/patologia , Camundongos , Camundongos Endogâmicos C57BL , Análise de Sequência de RNA , Análise de Célula Única , Transativadores/genética , Transativadores/metabolismo , Transcrição Genética/efeitos dos fármacos , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
7.
PLoS Genet ; 15(6): e1008181, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31216276

RESUMO

The increasing worldwide prevalence of Hepatocellular carcinoma (HCC), characterized by resistance to conventional chemotherapy, poor prognosis and eventually mortality, place it as a prime target for new modes of prevention and treatment. Hepatitis C Virus (HCV) is the predominant risk factor for HCC in the US and Europe. Multiple epidemiological studies showed that sustained virological responses (SVR) following treatment with the powerful direct acting antivirals (DAAs), which have replaced interferon-based regimes, do not eliminate tumor development. We aimed to identify an HCV-specific pathogenic mechanism that persists post SVR following DAAs treatment. We demonstrate that HCV infection induces genome-wide epigenetic changes by performing chromatin immunoprecipitation followed by next-generation sequencing (ChIP-seq) for histone post-translational modifications that are epigenetic markers for active and repressed chromatin. The changes in histone modifications correlate with reprogramed host gene expression and alter signaling pathways known to be associated with HCV life cycle and HCC. These epigenetic alterations require the presence of HCV RNA or/and expression of the viral proteins in the cells. Importantly, the epigenetic changes induced following infection persist as an "epigenetic signature" after virus eradication by DAAs treatment, as detected using in vitro HCV infection models. These observations led to the identification of an 8 gene signature that is associated with HCC development and demonstrate persistent epigenetic alterations in HCV infected and post SVR liver biopsy samples. The epigenetic signature was reverted in vitro by drugs that inhibit epigenetic modifying enzyme and by the EGFR inhibitor, Erlotinib. This epigenetic "scarring" of the genome, persisting following HCV eradication, suggest a novel mechanism for the persistent pathogenesis of HCV after its eradication by DAAs. Our study offers new avenues for prevention of the persistent oncogenic effects of chronic hepatitis infections using specific drugs to revert the epigenetic changes to the genome.


Assuntos
Carcinoma Hepatocelular/genética , Epigênese Genética/genética , Hepacivirus/genética , Hepatite C/genética , Neoplasias Hepáticas/genética , Idoso , Antivirais/administração & dosagem , Biópsia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Cromatina/genética , Epigênese Genética/efeitos dos fármacos , Receptores ErbB/antagonistas & inibidores , Cloridrato de Erlotinib , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Hepacivirus/patogenicidade , Hepatite C/tratamento farmacológico , Hepatite C/patologia , Hepatite C/virologia , Código das Histonas/genética , Histonas/genética , Interações Hospedeiro-Patógeno/genética , Humanos , Interferons/administração & dosagem , Fígado/efeitos dos fármacos , Fígado/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Transdução de Sinais/efeitos dos fármacos , Resposta Viral Sustentada
8.
Nat Biotechnol ; 37(8): 916-924, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31235917

RESUMO

Recent technical advancements have facilitated the mapping of epigenomes at single-cell resolution; however, the throughput and quality of these methods have limited their widespread adoption. Here we describe a high-quality (105 nuclear fragments per cell) droplet-microfluidics-based method for single-cell profiling of chromatin accessibility. We use this approach, named 'droplet single-cell assay for transposase-accessible chromatin using sequencing' (dscATAC-seq), to assay 46,653 cells for the unbiased discovery of cell types and regulatory elements in adult mouse brain. We further increase the throughput of this platform by combining it with combinatorial indexing (dsciATAC-seq), enabling single-cell studies at a massive scale. We demonstrate the utility of this approach by measuring chromatin accessibility across 136,463 resting and stimulated human bone marrow-derived cells to reveal changes in the cis- and trans-regulatory landscape across cell types and under stimulatory conditions at single-cell resolution. Altogether, we describe a total of 510,123 single-cell profiles, demonstrating the scalability and flexibility of this droplet-based platform.


Assuntos
Cromatina/química , Epigenômica/métodos , Microfluídica/métodos , Análise de Célula Única/métodos , Animais , Encéfalo/citologia , Linhagem Celular , Sobrevivência Celular , Cromatina/metabolismo , Técnicas de Química Combinatória , Desoxirribonucleases/farmacologia , Epigênese Genética/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Ensaios de Triagem em Larga Escala , Humanos , Leucócitos Mononucleares/metabolismo , Macrófagos/metabolismo , Camundongos
9.
Int J Nanomedicine ; 14: 3455-3468, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31190803

RESUMO

Background: Phospholysine phosphohistidine inorganic pyrophosphate phosphatase (LHPP) is a novel tumor suppressor. However, whether LHPP is effective to melanoma has not been investigated. Gene therapy provides a new strategy for the treatment of melanoma. Currently, it suffers from the lack of safe and effective gene delivery systems. Methods: A CRGDKGPDC peptide (iRGD) modified hybrid monomethoxy poly(ethylene glycol)-poly(D,L-lactide) nanoparticle (iDPP) was prepared and complexed with a LHPP plasmid, forming an iDPP/LHPP nanocomplex. The iDPP/LHPP nanocomplex was characterized by particle size distribution, zeta potential, morphology, cytotoxicity, and transfection efficiency. The antitumor efficacy of the nanocomplex against melanoma was studied both in vitro and in vivo. Further, the potential epigenetic changes in melanoma induced by iDPP/LHPP nanocomplex were evaluated. Results: The iDPP/LHPP nanocomplex showed high transfection efficiency and low toxicity. Moreover, the nanocomplex displayed a neutral charge that can meet the requirement of intravenous injection for targeted gene therapy. In vitro and in vivo experiments indicated that the iDPP/LHPP nanocomplex significantly inhibited the melanoma growth without causing notable adverse effects. We also found that LHPP played an important role in epigenetics. It regulated the expression of genes related to the proliferation and apoptosis chiefly at the level of transcription. Conclusion: This work demonstrates that the iDPP nanoparticle-delivered LHPP gene has a potential application in melanoma therapy through regulation of the genes associated with epigenetics.


Assuntos
Pirofosfatase Inorgânica/uso terapêutico , Melanoma Experimental/tratamento farmacológico , Nanopartículas/química , Animais , Antineoplásicos/farmacologia , Apoptose , Linhagem Celular Tumoral , Epigênese Genética/efeitos dos fármacos , Humanos , Melanoma Experimental/patologia , Camundongos Endogâmicos C57BL , Nanopartículas/ultraestrutura , Oligopeptídeos/química , Especificidade de Órgãos/efeitos dos fármacos , Poliésteres/química , Polietilenoglicóis/química
10.
Gene ; 711: 143941, 2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31242453

RESUMO

Inorganic arsenic is a well-known carcinogen associated with several types of cancer, but the mechanisms involved in arsenic-induced carcinogenesis are not fully understood. Recent evidence points to epigenetic dysregulation as an important mechanism in this process; however, the effects of epigenetic alterations in gene expression have not been explored in depth. Using microarray data and applying a multivariate clustering analysis in a Gaussian mixture model, we describe the alterations in DNA methylation around the promoter region and the impact on gene expression in HaCaT cells during the transformation process caused by chronic exposure to arsenic. Using this clustering approach, the genes were grouped according to their methylation and expression status in the epigenetic landscape, and the changes that occurred during the cellular transformation were identified adequately. Thus, we present a valuable method for identifying epigenomic dysregulation.


Assuntos
Arsênico/toxicidade , Transformação Celular Neoplásica/patologia , Metilação de DNA/efeitos dos fármacos , Perfilação da Expressão Gênica/métodos , Neoplasias Cutâneas/patologia , Animais , Linhagem Celular Tumoral , Transformação Celular Neoplásica/induzido quimicamente , Transformação Celular Neoplásica/genética , Epigênese Genética/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Transplante de Neoplasias , Análise de Sequência com Séries de Oligonucleotídeos , Regiões Promotoras Genéticas , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/genética
11.
Curr Top Med Chem ; 19(15): 1350-1362, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31215380

RESUMO

Macrophages are essential for supporting tissue homeostasis, regulating immune response, and promoting tumor progression. Due to its heterogeneity, macrophages have different phenotypes and functions in various tissues and diseases. It is becoming clear that epigenetic modification playing an essential role in determining the biological behavior of cells. In particular, changes of DNA methylation, histone methylation and acetylation regulated by the corresponding epigenetic enzymes, can directly control macrophages differentiation and change their functions under different conditions. In addition, epigenetic enzymes also have become anti-tumor targets, such as HDAC, LSD1, DNMT, and so on. In this review, we presented an overview of the latest progress in the study of macrophages phenotype and function regulated by epigenetic modifications, including DNA methylation and histone modifications, to better understand how epigenetic modification controls macrophages phenotype and function in inflammation-associated diseases, and the application prospect in anti-tumor.


Assuntos
Antineoplásicos/farmacologia , Epigênese Genética/efeitos dos fármacos , Inflamação/tratamento farmacológico , Macrófagos/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Acetilação/efeitos dos fármacos , Animais , Antineoplásicos/química , Metilação de DNA/efeitos dos fármacos , Epigênese Genética/genética , Histonas/efeitos dos fármacos , Histonas/metabolismo , Humanos , Inflamação/metabolismo , Inflamação/patologia , Macrófagos/metabolismo , Macrófagos/patologia , Metilação/efeitos dos fármacos , Neoplasias/metabolismo , Neoplasias/patologia
12.
Oxid Med Cell Longev ; 2019: 9214209, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31049141

RESUMO

The experiment was designed to clarify the effect and molecular mechanism of maternal genistein (GEN) on the lipid metabolism and developmental growth of offspring chicks. Laying broiler breeder (LBB) hens were supplemented with 40 mg/kg genistein (GEN), while the control group was fed with the low-soybean meal diet. The offspring chicks were grouped according to the mother generation with 8 replicates each. Hepatic transcriptome data revealed 3915 differentially expressed genes (DEGs, P adjusted < 0.05, fold change > 1.5 or fold change < 0.67) between chicks in the two groups. Maternal GEN activated the GH-IGF1-PI3K/Akt signaling pathway, which promoted the developmental processes and cellular amino acid metabolic processes, as well as inhibited the apoptotic process. GEN treatment significantly increased the weight gain, breast muscle percentage, and liver index in chicks. PANTHER clustering analysis suggested that maternal GEN enhanced the antioxidant activity of chicks by the upregulation of gene (SOD3, MT1, and MT4) expression. Accordingly, the activities of T-AOC and T-SOD in the liver were increased after GEN treatment. The overrepresentation tests revealed that maternal GEN influenced the glycolysis, unsaturated fatty acid biosynthesis, acyl-coenzyme A metabolism, lipid transport, and cholesterol metabolism in the chick livers. Hepatic cholesterol and long-chain fatty acid were significantly decreased after GEN treatment. However, the level of arachidonic acid was higher in the livers of the GEN-treated group compared with the CON group. Moreover, GEN treatment enhanced fatty acid ß-oxidation and upregulated PPARδ expression in the chick liver. ChIP-qPCR analysis indicated that maternal GEN might induce histone H3-K36 trimethylation in the promoter region of PPARδ gene (PPARD) through Iws1, methyltransferases. It also induced histone H4-K12 acetylation at the PPARD promoter through MYST2, which activated the PPAR signaling pathways in the chick livers. In summary, supplementing LBB hens with GEN can alter lipid metabolism in the offspring chicks through epigenetic modification and improve the antioxidative capability as well as growth performance.


Assuntos
Suplementos Nutricionais , Epigênese Genética/efeitos dos fármacos , Ácidos Graxos/biossíntese , Genisteína/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Galinhas , Feminino , Masculino
13.
Chemosphere ; 228: 586-594, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31059956

RESUMO

BACKGROUND: Benzo[a]pyrene (BaP) is an environmental pollutant known to cause teratogenesis. However, the mechanism underlying this teratogenic effect is not fully understood. Recently, the alteration of DNA methylation of imprinting genes has emerged as a specific epigenetic mechanism linking the impact of environmental pollutants on embryonic development to paternal exposures. The aim of this study was to investigate the transgenerational effects of paternal BaP exposure on the imprinting genes in mouse sperm DNA. METHODS: Male C57BL/6J mice received BaP (1.0 or 2.5 mg/kg) or olive oil twice a week for 12 weeks. The methylation status of 6 imprinting genes (H19, Meg3, Peg1, Peg3, Igf2 and Snrpn) was examined by bisulfite pyrosequencing of the sperm DNA of BaP-exposed F0 generation and their offspring. RESULTS: BaP exposure reduced the methylation levels in the imprinting genes H19 and Meg3 and increased the methylation levels of Peg1 and Peg3; however, no significant differences was observed for the methylation levels of Igf2 or Snrpn in the sperm DNA. Furthermore, BaP-exposed male mice were mated with unexposed female mice to generate F1-2 generations. The methylation levels of the 6 genes in the sperm DNA from F1-2 offspring showed a similar pattern as that of the F0 male. The effects were attenuated in F1-2 generations. CONCLUSIONS: Paternal BaP exposure altered the methylation levels of imprinting genes, implicating that imprinting genes are susceptible to environmental toxicants. Furthermore, a similar alteration was observed in the F1-2 generations although the attenuated in methylation in F2 generation, revealing a potential transgenerational effect.


Assuntos
Benzo(a)pireno/farmacologia , Metilação de DNA/efeitos dos fármacos , Impressão Genômica/genética , Exposição Paterna , Espermatozoides/efeitos dos fármacos , Animais , Poluentes Ambientais/farmacologia , Epigênese Genética/efeitos dos fármacos , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Reprodução/efeitos dos fármacos
14.
Chemosphere ; 229: 160-168, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31078030

RESUMO

To evaluate the body burdens of heavy metals correlated with health impact on school-age children living around a waste incinerator. A total of 81 children from the exposure area and 95 from the control area were recruited in our study. We measured the blood levels of chromium (Cr), cadmium (Cd) and lead (Pb) by an inductively coupled plasma mass spectrometer (ICP-MS), conducted comet assays, calculated the percentage of 5-methylcytosine (5 mC) and 5-hydroxymethylcytosine (5hmC) by MethylFlash methylated and a hydroxymethylated DNA quantification kit, and performed the flow cytometry to detect the expressions of surface antigens (including CD3+, CD19+, CD3+CD4+, CD3+CD8+, and CD3-CD16+ and/or CD56+) in peripheral lymphocytes. Besides, we measured hormonal levels, including triiodothyronine (T3), thyroxine (T4), free triiodothyronine (FT3), free thyroxine (FT4), and thyroid-stimulating hormone (TSH), and analyzed several regular hematological parameters. In addition, concentrations of heavy metals in environmental samples including rice, soils, vegetables, and drinking water were detected by ICP-MS. The mean blood levels of Cr, Cd, and Pb in the exposure group were all statistically higher than in the control group (2.57 vs. 0.79 µg/L; 1.83 vs. 1.81 µg/L; 44.00 vs. 32.31 µg/L, p < 0.01). The 5 mC and 5hmC levels in the exposure group were statistically lower (1.15% vs. 4.14%; 0.22% vs. 0.30%, p < 0.01), whereas the mean level of % tail DNA was statistically higher (10.10% vs. 8.62%, p < 0.01). Furthermore, the mean blood level of Cr and Pb was negatively correlated with the level of 5 mC (r = -0.279, r = -0.190, P < 0.05) in total population. In conclusion, children living in the vicinity of the municipal waste incinerator suffered increased body burdens of heavy metals (Cr, Cd, and Pb) associated with genotoxicity and epigenetic modifications.


Assuntos
Poluentes Ambientais/metabolismo , Poluentes Ambientais/toxicidade , Epigênese Genética/efeitos dos fármacos , Incineração , Metais Pesados/metabolismo , Metais Pesados/toxicidade , Resíduos , Carga Corporal (Radioterapia) , Criança , Feminino , Humanos , Masculino
15.
Anticancer Res ; 39(5): 2395-2403, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31092432

RESUMO

BACKGROUND/AIM: During cancer progression cells undergo epithelial-to-mesenchymal transition (EMT). Although EMT is a complex process, recently, it has been reported that CD146 overexpression in prostate cancer cells is sufficient to induce mesenchymal phenotype. The following study aimed to investigate whether the expression of CD146 is altered by an epigenetic modifier in prostate cancer cells, in vitro. MATERIALS AND METHODS: Three human prostate cancer cell lines were treated with 5-aza-2-deoxycytidine; the expression of CD146 and EMT-related factors was analyzed by RT-PCR and western Blot. The methylation status of the CD146 promoter area was assessed using bisulfite sequencing. RESULTS: Our data showed that, the expression of CD146 was evidently increased in all three studied cell lines in response to a demethylating agent, both at the mRNA and protein level, suggesting epigenetic regulation of the analyzed gene. However, there was no methylation in the studied CpG island in CD146 gene promoter. Moreover, the demethylating agent induced the expression of EMT-related transcription factors (SNAI1, SNAI2, TWIST1 and ZEB1), the pattern of which differed among the cell lines, as well as alterations in cell morphology; altogether accounting for the mesenchymal phenotype. CONCLUSION: The demethylating agent 5-aza-2-deoxycytidine triggers the expression of CD146 in prostate cancer cells independently on the methylation status of the analyzed CpG island fragment in CD146 gene promoter. Moreover, demethylation treatment induces a mesenchymal profile in prostate cancer cells.


Assuntos
Metilação de DNA/genética , Decitabina/farmacologia , Neoplasias da Próstata/genética , Antígeno CD146/genética , Linhagem Celular Tumoral , Metilação de DNA/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Regiões Promotoras Genéticas/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia
16.
Toxicol Lett ; 311: 98-104, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31063829

RESUMO

2,3,7,8-Tetrachlorobenzo-p-dioxin (TCDD) exposure during embryonic gonadal sex determination had been demonstrated to harm the ovarian development. However, its mechanism was unclear and possibly related to epigenetic regulation. In the present study, the pregnant rats were treated with TCDD (100 ng/kg/day or 500 ng/kg/day) or only vehicle and corn oil on the day 8-14 of gestation through the gavage with a stainless-steel feeding needle. The vaginal opening time and estrous cycle of female offspring rats (F1) were monitored twice a day. The ovarian histology, follicle count, real-time PCR, Western Blotting and DNA methylation analysis for Igf2 and H19 were carried out. The results showed that maternal TCDD exposure disrupted estrous cyclicity, resulted in aberrant concentration of serum E2 and FSH, and affected the number of primordial follicles, secondary follicles and corpus luteum. However, TCDD had no effect on the number of primary follicles and atresia follicles. Furthermore, the mRAN expression of imprinted genes Igf2 and H19 was down-regulated, and the IGF2 protein was also down-regulated. TCDD exposure did not alter the mean methylation rate of Igf2 DMR2 and H19 ICR, and only some CpG sites throughout them were hypermethylated in high-dose TCDD rats. In conclusion, maternal exposure of TCDD could affect the ovary development and functions which were possibly associated with down-regulation expression of IGF2 and H19. However, it was not entirely clear whether the impairment of ovary by TCDD was related to the methylation pattern of Igf2 and H19 ICR.


Assuntos
Epigênese Genética/efeitos dos fármacos , Fator de Crescimento Insulin-Like II/genética , Doenças Ovarianas/induzido quimicamente , Ovário/efeitos dos fármacos , Dibenzodioxinas Policloradas/toxicidade , Efeitos Tardios da Exposição Pré-Natal , RNA Longo não Codificante/genética , Animais , Ilhas de CpG/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Estradiol/sangue , Ciclo Estral/sangue , Ciclo Estral/efeitos dos fármacos , Ciclo Estral/genética , Feminino , Hormônio Foliculoestimulante/sangue , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Impressão Genômica/efeitos dos fármacos , Idade Gestacional , Fator de Crescimento Insulin-Like II/metabolismo , Exposição Materna , Doenças Ovarianas/genética , Doenças Ovarianas/metabolismo , Doenças Ovarianas/patologia , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/metabolismo , Folículo Ovariano/patologia , Ovário/metabolismo , Ovário/patologia , Gravidez , RNA Longo não Codificante/metabolismo , Ratos , Ratos Sprague-Dawley
18.
Environ Int ; 127: 601-614, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30986742

RESUMO

BACKGROUND: Long-term exposure to fine particulate matter (PM2.5) can causally contribute to progression of atherosclerosis, risk of ischemic heart disease and death, but the underlying mechanism is little known. Since DNA methylation impacts the process of heart disease, it might be useful in exploring potential mechanistic pathways linking PM2.5 exposure and heart disease. OBJECTIVES: Here, we investigated the PM2.5-induced ADRB2 hypermethylation and the involving epigenetic mechanism of PM2.5-induced cardiomyocytes apoptosis and cardiac dysfunction. METHODS AND RESULTS: In vitro, PM2.5 markedly augmented cardiotoxicity including oxidative damage and apoptosis in cardiomyocytes AC16 as well as epigenetic alteration. DNA methylation profiling revealed a significant gene-ADRB2 was involved in the cardiac relative GO and KEGG pathways. Methylation chip and Bisulfite Sequencing PCR (BSP) both identified the hypermethylation status of ADRB2 which encodes ß2-Adrenergic receptor (ß2AR). Mechanistic study showed ADRB2 hypermethylation-induced down-regulation of ß2AR inhibited PI3K/Akt and then activated Bcl-2/BAX and p53 pathway in AC16. The transgenic cell lines showed over-expression of ADRB2 weakened the PM2.5-induced cardiomyocytes apoptosis in opposite way, but was augmented by PI3K inhibitor (LY294002). In vivo, echocardiography showed the heart contractile function was decreased after SD rats intratracheal instillation of PM2.5 for 30 days. The myocardial interstitial edema, myocardial gap expansion and myofibril disorder in PM2.5 treated group were observed in rats heart tissue. What's more, basal expression of ß2AR and VEGFR2 decreased in heart tissue as the dosage of PM2.5 increasing, meanwhile PM2.5 markedly attenuated PI3K/Akt pathway followed by augmented Bcl-2/BAX and p53 pathway, thus caused a greater number of TUNEL positive cardiomyocytes resulted in cardiac dysfunction in vivo. CONCLUSIONS: PM2.5 exposure could cause the myocardial ADRB2 hypermethylation and activate the ß2AR/PI3K/Akt pathway, resulted in PM2.5-induced cardiomyocytes apoptosis and cardiac dysfunction. Our study suggested that the ADRB2 demethylation or ADRB2/ß2AR activation may serve as a potential pathway to prevent cardiac dysfunction induced by PM2.5 exposure.


Assuntos
Metilação de DNA/efeitos dos fármacos , Cardiopatias/induzido quimicamente , Miócitos Cardíacos/efeitos dos fármacos , Material Particulado/farmacologia , Receptores Adrenérgicos beta 2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Epigênese Genética/efeitos dos fármacos , Masculino , Miócitos Cardíacos/citologia , Material Particulado/toxicidade , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley
19.
Int J Mol Sci ; 20(8)2019 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-31013830

RESUMO

Breast cancer is the most common malignancy in women worldwide and can be categorized into several subtypes according to histopathological parameters or genomic signatures. Such heterogeneity of breast cancer can arise from the reactivation of mammary stem cells in situ during tumorigenesis. Moreover, different breast cancer subtypes exhibit varieties of cancer incidence, therapeutic response, and patient prognosis, suggesting that a specific therapeutic protocol is required for each breast cancer subtype. Recent studies using molecular and cellular assays identified a link between specific genetic/epigenetic alterations and distinct cells of origin of breast cancer subtypes. These alterations include oncogenes, tumor suppressor genes, and cell-lineage determinants, which can induce cell reprogramming (dedifferentiation and transdifferentiation) among two lineage-committed mammary epithelial cells, namely basal and luminal cells. The interconversion of cell states through cell reprogramming into the intermediates of mammary stem cells can give rise to heterogeneous breast cancers that complicate effective therapies of breast cancer. A better understanding of mechanisms underlying cell reprogramming in breast cancer can help in not only elucidating tumorigenesis but also developing therapeutics for breast cancer. This review introduces recent findings on cancer gene-mediated cell reprogramming in breast cancer and discusses the therapeutic potential of targeting cell reprogramming.


Assuntos
Neoplasias da Mama/etiologia , Transformação Celular Neoplásica , Reprogramação Celular , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Linhagem da Célula/genética , Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Reprogramação Celular/efeitos dos fármacos , Reprogramação Celular/genética , Epigênese Genética/efeitos dos fármacos , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Feminino , Humanos , Terapia de Alvo Molecular , Células-Tronco/metabolismo , Células-Tronco/patologia
20.
Cell Commun Signal ; 17(1): 38, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-31014357

RESUMO

BACKGROUND: The NOV gene product, CCN3, has been reported in a diverse range of tumors to serve as a negative growth regulator, while acting as a tumor suppressor in Chronic Myelogenous Leukemia (CML). However, the precise mechanism of its silencing in CML is poorly understood. In the current study, we aimed to query if the gene regulation of CCN3 is mediated by the promoter methylation in the patients with CML. In addition, to clarify whether the epigenetic silencing is affected by BCR-ABL1 inhibition, we assessed the methylation status in the patients at different time intervals following the tyrosine kinase inhibition using imatinib therapy, as the first-line treatment for this type of leukemia. METHODS: To address this issue, we applied bisulfite-sequencing technique as a high-resolution method to study the regulatory segment of the CCN3 gene. The results were analyzed in newly diagnosed CML patients as well as following imatinib therapy. We also evaluated the correlation of CCN3 promoter methylation with BCR-ABL1 levels. RESULTS: Our findings revealed that the methylation occurs frequently in the promoter region of CML patients showing a significant increase of the methylated percentage at the CpG sites compared to normal individuals. Interestingly, this hypermethylation was indicated to be independent of BCR-ABL1 titers in both groups, which might suggest a mechanism beyond the BCR-ABL1 function. CONCLUSION: Despite suggesting that the CCN3 hypermethylation acts as a molecular mechanism independent of BCR-ABL1 function in CML patients, this scenario requires further validation by complementary experiments. In the case of acting upstream of BCR-ABL1 signaling, the methylation marker can provide early detection and a novel platform for targeted epigenetic modifiers for efficient treatment in imatinib resistant patients.


Assuntos
Metilação de DNA/efeitos dos fármacos , Proteínas de Fusão bcr-abl/sangue , Mesilato de Imatinib/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Proteína Sobre-Expressa em Nefroblastoma/genética , Adulto , Idoso , Antineoplásicos/uso terapêutico , Ilhas de CpG , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Feminino , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas , Inibidores de Proteínas Quinases/uso terapêutico
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