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1.
Medicine (Baltimore) ; 98(38): e17225, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31567982

RESUMO

The present study is to analyze the difference of gene methylation in early cervical adenocarcinoma and to find molecular markers for predicting the occurrence and development of cervical adenocarcinoma.A total of 15 cases of primary cervical adenocarcinoma and 10 cases of primary cervical squamous cell carcinoma at stages IB1 or IIA1 were included in the study. Infinium MethylationEPIC BeadChip (850K) was used to screen specifically expressed genes in cervical adenocarcinoma tissues. Bisulfite sequencing polymerase chain reaction (BSP) and quantitative real-time polymerase chain reaction (qRT-PCR) were used to verify the methylation levels in cervical adenocarcinoma, cervical squamous cell carcinoma, and normal cervical tissues.Sex determining region Y-box 1 (SOX1) and cyclin D1 (CCND1) genes participated in multiple signaling pathways, being the central nodes of gene regulatory networks. SOX1 gene, but not CCND1 gene, was a specifically methylated gene in cervical adenocarcinoma according to BSP. According to qRT-PCR, methylation level of SOX1 in cervical adenocarcinoma tissues is significantly different from that in cervical squamous cell carcinoma tissues or normal cervical tissues, and the methylation level of CCND1 in cervical adenocarcinoma tissues or cervical squamous cell carcinoma tissues is significantly different from that in normal cervical tissues.The present study demonstrates that tumor-suppressor gene SOX1 is a methylation-specific expression gene of cervical adenocarcinoma and is expected to become a specific molecular marker for the diagnosis of cervical adenocarcinoma. However, CCND1 gene was not proven to be a specific methylation expression gene in cervical adenocarcinoma in the present study.


Assuntos
Adenocarcinoma/genética , Metilação de DNA/genética , Fatores de Transcrição SOXB1/genética , Neoplasias do Colo do Útero/genética , Adenocarcinoma/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Colo do Útero/metabolismo , Ciclina D1/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes/genética , Marcadores Genéticos/genética , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Neoplasias do Colo do Útero/metabolismo
2.
Anticancer Res ; 39(10): 5361-5367, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31570430

RESUMO

BACKGROUND/AIM: The mechanism responsible for B-cell translocation gene 1 (BTG1) down-regulation in breast carcinoma remains unknown. We examined the BTG1 expression status in breast carcinoma cells and investigated the mechanism underlying the observed alterations. MATERIALS AND METHODS: Four breast carcinoma cell lines (SK-BR-3, MDA-MB-231, T-47D, and MCF-7), and one normal mammary epithelial cell line (MCF-10A) were analyzed. BTG1 expression was examined using quantitative reverse transcription polymerase chain reaction (PCR) and western blot. Methylation status of the BTG1 promoter was analyzed using methylation-specific PCR (MSP). To investigate the effect of methylation on BTG1, the cells were treated with a demethylating agent. RESULTS: The carcinoma cells expressed significantly lower levels of BTG1 mRNA and protein than normal cells. The BTG1 promoter was highly methylated in the carcinoma cells. 5-aza-2-deoxycytidine significantly restored BTG1 expression. CONCLUSION: Down-regulation of BTG1 expression through epigenetic repression is involved in mammary carcinogenesis. BTG1 is a potential diagnostic marker and therapeutic target for breast carcinoma.


Assuntos
Neoplasias da Mama/genética , Metilação de DNA/genética , Regulação para Baixo/genética , Proteínas de Neoplasias/genética , Regiões Promotoras Genéticas/genética , Carcinogênese/genética , Linhagem Celular Tumoral , Epigênese Genética/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Células MCF-7 , RNA Mensageiro/genética
3.
Anticancer Res ; 39(10): 5381-5391, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31570433

RESUMO

BACKGROUND/AIM: Long noncoding RNAs (lncRNAs) are noncoding transcripts that are >200 nucleotides in length. However, the biological functions and regulation mechanisms of lncRNAs in gastric carcinogenesis remain unknown. MATERIALS AND METHODS: The expression levels of Linc00472 were analyzed by real-time PCR. The DNA methylation status was assessed using Combined Bisulfite Restriction Analysis (COBRA). The biological role of Linc00472 was assessed in AGS cells with Linc00472 overexpression. RESULTS: Using the next-generation sequencing approach, we identified DNA methylation-associated lncRNAs in gastric cancer cells. Among them, the expression level of Linc00472 significantly decreased in gastric cancer tissues compared to adjacent normal tissues. Furthermore, we observed a more frequent hypermethylation of CpG islands upstream of Linc00472 in gastric cancer tissues. Ectopic Linc00472 expression could significantly inhibit gastric cancer cell growth and migration. CONCLUSION: Epigenetically regulated Linc00472 expression plays a crucial role in modulating gastric cancer cell growth and motility.


Assuntos
Metilação de DNA/genética , RNA Longo não Codificante/genética , Neoplasias Gástricas/genética , Carcinogênese/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Ilhas de CpG/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos
4.
Anticancer Res ; 39(10): 5449-5459, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31570439

RESUMO

BACKGROUND/AIM: Epigenetic abnormalities in microRNAs (miRNAs) have not been analyzed in samples other than pancreaticobiliary tissues in patients with pancreaticobiliary cancer (PBC). To identify miRNAs specific for PBC, the present study analyzed the methylation of tumor-suppressive miRNAs in bile from patients with pancreaticobiliary diseases. MATERIALS AND METHODS: Bile was collected endoscopically or percutaneously from 52 patients with pancreatic cancer, 26 with biliary tract cancer, and 20 with benign pancreaticobiliary diseases. Sequences encoding 16 tumor-suppressive miRNAs were amplified by polymerase chain reaction and sequenced, and their methylation rates were determined. RESULTS: The methylation rates of miR-1247 and miR-200a were significantly higher in patients with pancreatic cancer, and biliary tract cancer than in those with benign diseases, and the methylation rate of miR-200b was significantly higher in patients with pancreatic cancer than in those with benign diseases. CONCLUSION: Methylation of miR-1247, miR-200a, and miR-200b in bile may be useful for distinguishing PBC from benign diseases.


Assuntos
Neoplasias do Sistema Biliar/genética , Metilação de DNA/genética , MicroRNAs/genética , Neoplasias Pancreáticas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Bile/metabolismo , Epigenômica/métodos , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Genes Supressores de Tumor/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade
5.
Anticancer Res ; 39(8): 4003-4010, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31366481

RESUMO

Epstein-Barr virus (EBV)-associated gastric cancer (GC) (EBVaGC) is classified as one of four GC subtypes by comprehensive molecular characterization. Though the mechanism of tumorigenesis by EBV infection has not yet been fully clarified, EBV infection might contribute to the malignant transformation of GC cells by involving various cellular processes and signaling pathways. EBVaGC has shown the following distinct characteristics in contrast to other subtypes: extreme DNA hypermethylation, recurrent phosphatidylinositol 4,5-biphosphate 3-kinase catalytic subunit alpha isoform (PIK3CA) mutations, overexpression of programmed cell death ligand 1/2 (PD-L1/2), and occasional immune cell signaling activation. Therefore, using these molecular features as guides, targeted agents need to be evaluated in clinical trials for EBVaGC. Accordingly, this review uses the best available evidence to focus on novel therapeutic approaches using the distinct pathologic characteristics of EBVaGC patients.


Assuntos
Carcinogênese/genética , Infecções por Vírus Epstein-Barr/terapia , Neoplasias Gástricas/terapia , Classe I de Fosfatidilinositol 3-Quinases/genética , Metilação de DNA/genética , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/virologia , Regulação Neoplásica da Expressão Gênica/genética , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/patogenicidade , Humanos , Neoplasias Gástricas/genética , Neoplasias Gástricas/virologia
6.
Anticancer Res ; 39(8): 4129-4136, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31366497

RESUMO

BACKGROUND/AIM: 5-Aza-2-deoxycytidine (5-Aza-CdR) enhances the sensitivity to 5-fluorouracil (5-FU), but the molecular mechanism is not fully understood. The aim of this study was to investigate the molecular mechanism that enhances the sensitivity to 5-FU treated with 5-Aza-CdR via thymidine phosphorylase (TP). MATERIALS AND METHODS: The sensitivity to drugs was determined on several cancer cell lines by the MTT assay. Protein and mRNA levels were examined by immunoblot and RT-PCR, respectively. Gene silencing, binding of Sp1 to DNA and methylation of DNA was performed by siRNA, ChIP assay and sodium bisulfate genomic sequencing, respectively. RESULTS: Sp1-binding sites in the TP promoter were methylated in epidermoid carcinoma. 5-Aza-CdR demethylated Sp1-binding sites and enhanced sensitivity to 5-FU. CONCLUSION: Demethylation of Sp1-binding sites by 5-Aza-CdR was a key factor enhancing 5-FU sensitivity, which may enable more effective treatments for cancer patients with the combination of 5-Aza-CdR and 5-FU.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Metilação de DNA/genética , Resistencia a Medicamentos Antineoplásicos/genética , Fator de Transcrição Sp1/genética , Timidina Fosforilase/genética , Sítios de Ligação/efeitos dos fármacos , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Proteínas de Ligação a DNA/genética , Decitabina/metabolismo , Fluoruracila/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inativação Gênica , Humanos , Regiões Promotoras Genéticas/efeitos dos fármacos , RNA Mensageiro/genética , Timidina Fosforilase/química
7.
Nature ; 571(7766): 489-499, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31341302

RESUMO

Epigenetic research has accelerated rapidly in the twenty-first century, generating justified excitement and hope, but also a degree of hype. Here we review how the field has evolved over the last few decades and reflect on some of the recent advances that are changing our understanding of biology. We discuss the interplay between epigenetics and DNA sequence variation as well as the implications of epigenetics for cellular memory and plasticity. We consider the effects of the environment and both intergenerational and transgenerational epigenetic inheritance on biology, disease and evolution. Finally, we present some new frontiers in epigenetics with implications for human health.


Assuntos
Doença/genética , Epigênese Genética/genética , Epigenômica/tendências , Interação Gene-Ambiente , Envelhecimento/genética , Animais , Cromatina/genética , Cromatina/metabolismo , Metilação de DNA/genética , Variação Genética/genética , Humanos , Neoplasias/genética
8.
Nat Commun ; 10(1): 2950, 2019 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-31270318

RESUMO

X-chromosome inactivation triggers fusion of A/B compartments to inactive X (Xi)-specific structures known as S1 and S2 compartments. SMCHD1 then merges S1/S2s to form the Xi super-structure. Here, we ask how S1/S2 compartments form and reveal that Xist RNA drives their formation via recruitment of Polycomb repressive complex 1 (PRC1). Ablating Smchd1 in post-XCI cells unveils S1/S2 structures. Loss of SMCHD1 leads to trapping Xist in the S1 compartment, impairing RNA spreading into S2. On the other hand, depleting Xist, PRC1, or HNRNPK precludes re-emergence of S1/S2 structures, and loss of S1/S2 compartments paradoxically strengthens the partition between Xi megadomains. Finally, Xi-reactivation in post-XCI cells can be enhanced by depleting both SMCHD1 and DNA methylation. We conclude that Xist, PRC1, and SMCHD1 collaborate in an obligatory, sequential manner to partition, fuse, and direct self-association of Xi compartments required for proper spreading of Xist RNA.


Assuntos
Proteínas Cromossômicas não Histona/metabolismo , Cromossomos de Mamíferos/genética , Complexo Repressor Polycomb 1/metabolismo , RNA Longo não Codificante/metabolismo , Cromossomo X/química , Cromossomo X/genética , Animais , Metilação de DNA/genética , Histonas/metabolismo , Lisina/metabolismo , Camundongos , Modelos Genéticos , Inativação do Cromossomo X/genética
9.
Biol Res ; 52(1): 31, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31182157

RESUMO

BACKGROUND: The purpose of the present study was to investigate the role of the methylation status of the DACT1 gene on the invasion and metastasis of nasopharyngeal carcinoma cells. METHODS: The levels of methylation and expression of the DACT1 gene in nasopharyngeal carcinoma tissues and CNE2 cells were determined by methylation-specific PCR and RT-PCR, respectively. CNE2 cells were treated with 5-aza-2-deoxycytidine, and the variation in the methylation status of the DACT1 gene was detected, as well as the influence of methylation on invasiveness of nasopharyngeal carcinoma cells. RESULTS: The DACT1 gene was hyper-methylated in 44 of 62 cases of nasopharyngeal carcinoma. The DACT1 gene was hyper-methylated in 32 of 38 cases of nasopharyngeal carcinoma with lymph node metastasis, and the DACT1 gene was hyper-methylated in 7 of 24 cases of nasopharyngeal carcinoma without lymph node metastasis. The DACT1 mRNA level was weakly expressed or not expressed in all nasopharyngeal carcinoma tissues with hyper-methylated DACT1 genes; however, the DACT1 mRNA level was highly expressed in nasopharyngeal carcinoma tissues with low expression of the methylated DACT1 gene. The DACT1 gene was hyper-methylated and not expressed in CNE2 cells that did not have 5-aza-2-deoxycytidine treatment. After 5-aza-2-deoxycytidine treatment, the DACT1 gene was demethylated and the expression of DACT1 was restored. Moreover, the invasion ability was inhibited in CNE2 cells treated with 5-aza-2-deoxycytidine. CONCLUSION: The expression of DACT1 was related to the methylation status. High expression of DACT1 may inhibit the invasion and metastasis of nasopharyngeal carcinoma cells.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Metilação de DNA/genética , Carcinoma Nasofaríngeo/secundário , Neoplasias Nasofaríngeas/patologia , Proteínas Nucleares/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Metilação de DNA/fisiologia , Feminino , Humanos , Masculino , Carcinoma Nasofaríngeo/genética , Neoplasias Nasofaríngeas/genética , Invasividade Neoplásica , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/metabolismo , Regiões Promotoras Genéticas
10.
Cancer Sci ; 110(8): 2629-2642, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31215104

RESUMO

Multigenerational adverse effects from the environment such as nutrition and chemicals are among important concerns in environmental health issues. Previously, we have found that arsenite exposure of only F0 females during their pregnancy increases hepatic tumors in the F2 males in C3H mice. In the current study, we investigated the association of DNA methylation with the hepatic tumor increase in the F2 males of the arsenite group. Reduced-representation bisulfite sequencing analysis newly identified that DNA methylation levels of regions around the transcriptional start sites of Tmem54 and Cd74 were decreased and the expression of these genes were significantly increased in the hepatic tumors of F2 males of the arsenite group. The associations between DNA methylation in these regions and gene expression changes were confirmed by treatment of murine hepatoma cell lines and hepatic stellate cell line with 5-aza-2'-deoxycytidine. Overexpression of Cd74 in Hepa1c1c7 cells increased Trib3 expression and suppressed the expression of tumor suppressor genes Id3 and Atoh8. Human database analysis using the Cancer Genome Atlas indicated that TMEM54, CD74, and TRIB3 were significantly increased and that ATOH8 was decreased in hepatocellular carcinoma. The data also showed that high expression of TMEM54 and TRIB3 and low expression of ATOH8 were associated with poor survival. These results suggested that an increase in Tmem54 and Cd74 expression via DNA methylation reduction was involved in the tumor increase in the F2 male offspring by gestational arsenite exposure of F0 females. This study also suggested that genes downstream of Cd74 were involved in tumorigenesis.


Assuntos
Arsenitos/efeitos adversos , Carcinoma Hepatocelular/genética , Metilação de DNA/genética , Neoplasias Hepáticas/genética , Animais , Antígenos de Diferenciação de Linfócitos B/genética , Antígenos de Neoplasias/genética , Carcinoma Hepatocelular/induzido quimicamente , Linhagem Celular Tumoral , Feminino , Expressão Gênica/genética , Antígenos de Histocompatibilidade Classe II/genética , Neoplasias Hepáticas/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos C3H , Gravidez
11.
Biochim Biophys Acta Rev Cancer ; 1872(1): 74-79, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31201828

RESUMO

A prominent mucinous phenotype is observed in 10-15% of all colorectal cancers (CRCs). They are associated with a proximal location, and more commonly observed among tumors with mismatch repair defects and a promoter CpG methylator phenotype. However, none of these features has been clearly linked mechanistically to this mucinous subtype. Here, we propose that bacterial biofilms could represent a currently unappreciated contributor to mucinous CRC formation. The colonic microbiome and biofilms in particular, are emerging as important factors in tumor initiation and progression. Intriguingly, biofilms preferentially accompany proximal tumors, suggesting that there may be a direct mechanistic link with mucinous CRCs.


Assuntos
Adenocarcinoma Mucinoso/microbiologia , Biofilmes/crescimento & desenvolvimento , Biomarcadores Tumorais/genética , Neoplasias Colorretais/microbiologia , Adenocarcinoma Mucinoso/genética , Adenocarcinoma Mucinoso/patologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Ilhas de CpG/genética , Metilação de DNA/genética , Humanos , Instabilidade de Microssatélites
12.
Nat Commun ; 10(1): 2548, 2019 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-31186427

RESUMO

Epigenetic processes, including DNA methylation (DNAm), are among the mechanisms allowing integration of genetic and environmental factors to shape cellular function. While many studies have investigated either environmental or genetic contributions to DNAm, few have assessed their integrated effects. Here we examine the relative contributions of prenatal environmental factors and genotype on DNA methylation in neonatal blood at variably methylated regions (VMRs) in 4 independent cohorts (overall n = 2365). We use Akaike's information criterion to test which factors best explain variability of methylation in the cohort-specific VMRs: several prenatal environmental factors (E), genotypes in cis (G), or their additive (G + E) or interaction (GxE) effects. Genetic and environmental factors in combination best explain DNAm at the majority of VMRs. The CpGs best explained by either G, G + E or GxE are functionally distinct. The enrichment of genetic variants from GxE models in GWAS for complex disorders supports their importance for disease risk.


Assuntos
Metilação de DNA/genética , DNA/sangue , Interação Gene-Ambiente , Estudos de Coortes , Epigênese Genética , Feminino , Sangue Fetal , Genótipo , Humanos , Recém-Nascido , Masculino , Gravidez , Fatores de Risco
13.
Nat Commun ; 10(1): 2226, 2019 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-31110221

RESUMO

Lineage commitment and tumorigenesis, traits distinguishing stem cells, have not been well characterized and compared in mesenchymal stem cells derived from human dental pulp (DP-MSCs) and bone marrow (BM-MSCs). Here, we report DP-MSCs exhibit increased osteogenic potential, possess decreased adipogenic potential, form dentin pulp-like complexes, and are resistant to oncogenic transformation when compared to BM-MSCs. Genome-wide RNA-seq and differential expression analysis reveal differences in adipocyte and osteoblast differentiation pathways, bone marrow neoplasm pathway, and PTEN/PI3K/AKT pathway. Higher PTEN expression in DP-MSCs than in BM-MSCs is responsible for the lineage commitment and tumorigenesis differences in both cells. Additionally, the PTEN promoter in BM-MSCs exhibits higher DNA methylation levels and repressive mark H3K9Me2 enrichment when compared to DP-MSCs, which is mediated by increased DNMT3B and G9a expression, respectively. The study demonstrates how several epigenetic factors broadly affect lineage commitment and tumorigenesis, which should be considered when developing therapeutic uses of stem cells.


Assuntos
Carcinogênese/genética , Polpa Dentária/citologia , Células-Tronco Mesenquimais/patologia , Osteogênese/genética , PTEN Fosfo-Hidrolase/metabolismo , Adipócitos/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Células da Medula Óssea/patologia , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Carcinogênese/patologia , Diferenciação Celular/genética , Células Cultivadas , Criança , DNA (Citosina-5-)-Metiltransferases/metabolismo , Metilação de DNA/genética , Polpa Dentária/patologia , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Antígenos de Histocompatibilidade/metabolismo , Código das Histonas/genética , Histona-Lisina N-Metiltransferase/metabolismo , Humanos , Células-Tronco Mesenquimais/metabolismo , Pessoa de Meia-Idade , Osteoblastos/metabolismo , Osteossarcoma/genética , Osteossarcoma/patologia , PTEN Fosfo-Hidrolase/genética , Regiões Promotoras Genéticas/genética , Análise de Sequência de RNA
14.
Cell Mol Biol Lett ; 24: 28, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31061665

RESUMO

Background: Hypoxia-inducible factor-1α (HIF-1α) is a transcription factor with a pivotal role in physiological and pathological responses to hypoxia. While HIF-1α is known to be involved in hypoxia-induced upregulation of microRNA (miRNA) expression, HIF-1α is also targeted by miRNAs. In this study, miRNAs targeting HIF-1α were identified and their effects on its expression and downstream target genes under hypoxic conditions were investigated. Cell migration under the same conditions was also assessed. Methods: microRNAs that target HIF-1α were screened using 3'-untranslated region luciferase (3'-UTR-luciferase) reporter assays. The expression levels of HIF-1α and its downstream target genes after transfection with miRNA were assessed using quantitative RT-PCR and western blot analyses. The effect of the miRNAs on the transcriptional activity of HIF-1α was determined using hypoxia-responsive element luciferase (HRE-luciferase) assays. Cell migration under hypoxia was examined using the wound-healing assay. Results: Several of the 19 screened miRNAs considerably decreased the luciferase activity. Transfection with miR-200c had substantial impact on the expression level and transcription activity of HIF-1α. The mRNA level of HIF-1α downstream genes decreased in response to miR-200c overexpression. MiR-200c inhibited cell migration in normoxia and, to a greater extent, in hypoxia. These effects were partly reversed by HIF-1α expression under hypoxic conditions. Conclusion: miR-200c negatively affects hypoxia-induced responses by downregulating HIF-1α, a key regulator of hypoxia. Therefore, overexpression of miR-200c might have therapeutic potential as an anticancer agent that inhibits tumor hypoxia.


Assuntos
Movimento Celular/genética , Regulação para Baixo/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , MicroRNAs/metabolismo , Regiões 3' não Traduzidas/genética , Sequência de Bases , Hipóxia Celular/genética , Linhagem Celular Tumoral , Metilação de DNA/genética , Regulação Neoplásica da Expressão Gênica , Genes Reporter , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Luciferases/metabolismo , MicroRNAs/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcrição Genética , Regulação para Cima/genética , Cicatrização
15.
Anticancer Res ; 39(5): 2289-2298, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31092420

RESUMO

BACKGROUND/AIM: We previously identified that promoter DNA methylation of cysteine dioxygenase type 1 (CDO1) and homeobox only protein homeobox (HOPX) were both cancer specific, and have a clinical potential as prognostic biomarkers in breast cancer (BC). The present study compared the differential prognostic relevance of methylation status of the CDO1 and HOPX genes in BC. MATERIALS AND METHODS: Methylation levels (TaqMethVs) were quantified in 7 BC cell lines and 133 BC patients by TaqMan methylation-specific PCR and functional traits were explored for CDO1. RESULTS: TaqMethVs were associated between CDO1 and HOPX (r2=0.072, p=0.002). Multivariate Cox proportional hazards model could identify CDO1 hypermethylation as well as Ki-67 as independent prognostic factors related to disease-specific survival (p=0.016, p<0.001). Overexpression of CDO1 decreased the anchorage-independent growth capacity in BC cell lines. CONCLUSION: CDO1 is a definite tumor suppressor gene, while its prognostic relevance was more than expected in the context of its functional relevance.


Assuntos
Neoplasias da Mama/genética , Cisteína Dioxigenase/genética , Metilação de DNA/genética , Proteínas de Homeodomínio/genética , Proteínas Supressoras de Tumor/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Antígeno Ki-67/genética , Pessoa de Meia-Idade , Prognóstico , Regiões Promotoras Genéticas , Modelos de Riscos Proporcionais
16.
Anticancer Res ; 39(5): 2361-2367, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31092428

RESUMO

BACKGROUND/AIM: Previous studies have documented that osteoprotegerin (OPG) is involved in the development and progression of several human malignancies. However, OPG has also been shown to act as a tumor suppressor. The aim of this study was to examine the expression status of OPG in ovarian carcinoma cells and investigate the underlying mechanism responsible for alterations in OPG expression. MATERIALS AND METHODS: The expression levels of OPG mRNA and protein were assessed in human ovarian carcinoma cell lines. The methylation status of the OPG promoter region was determined using the bisulfite pyrosequencing technique. The effects of demethylation on OPG expression were also analyzed. RESULTS: The human ovarian carcinoma cell lines, SW 626, OVCAR-3, ES-2, TOV-112D, and TOV-21G, expressed significantly lower levels of OPG mRNA and protein than the normal human ovarian epithelial cell line, HS823.Tc. Moreover, three CpG sites in the OPG promoter region were highly methylated in the SW 626, OVCAR-3, ES-2, and TOV-112D ovarian carcinoma cell lines compared to normal control cells. Furthermore, in all the examined ovarian carcinoma cell lines, treatment with the demethylating agent, 5-aza-2-deoxycytidine, resulted in significantly increased expression levels of OPG mRNA and protein compared to the respective pre-treatment levels. CONCLUSION: OPG expression was down-regulated in the studied ovarian carcinoma cells compared to the normal control cells, while demethylation significantly restored OPG expression in the OPG-down-regulated cell lines. Our results suggest that OPG down-regulation in ovarian carcinoma occurs, at least partly, through epigenetic repression, suggesting its involvement in ovarian carcinogenesis.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Epitelial do Ovário/genética , Metilação de DNA/genética , Osteoprotegerina/genética , Carcinogênese/genética , Carcinoma Epitelial do Ovário/patologia , Linhagem Celular Tumoral , Epigênese Genética/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Regiões Promotoras Genéticas
17.
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
18.
Nat Commun ; 10(1): 2094, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-31064978

RESUMO

Multiple sclerosis (MS) is an inflammatory, demyelinating disease of the central nervous system with a modest concordance rate in monozygotic twins, which strongly argues for involvement of epigenetic factors. We observe highly similar peripheral blood mononuclear cell-based methylomes in 45 MS-discordant monozygotic twins. Nevertheless, we identify seven MS-associated differentially methylated positions (DMPs) of which we validate two, including a region in the TMEM232 promoter and ZBTB16 enhancer. In CD4 + T cells we find an MS-associated differentially methylated region in FIRRE. Additionally, 45 regions show large methylation differences in individual pairs, but they do not clearly associate with MS. Furthermore, we present epigenetic biomarkers for current interferon-beta treatment, and extensive validation shows that the ZBTB16 DMP is a signature for prior glucocorticoid treatment. Taken together, this study represents an important reference for epigenomic MS studies, identifies new candidate epigenetic markers, and highlights treatment effects and genetic background as major confounders.


Assuntos
Metilação de DNA/genética , Doenças em Gêmeos/genética , Epigênese Genética , Predisposição Genética para Doença , Esclerose Múltipla/genética , Adulto , Idoso , Biomarcadores , Doenças em Gêmeos/sangue , Elementos Facilitadores Genéticos/genética , Epigenômica/métodos , Feminino , Humanos , Leucócitos Mononucleares , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Esclerose Múltipla/sangue , Regiões Promotoras Genéticas/genética , Proteína com Dedos de Zinco da Leucemia Promielocítica/genética , RNA Longo não Codificante/genética , Gêmeos Monozigóticos , Adulto Jovem
19.
Nat Commun ; 10(1): 2119, 2019 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-31073172

RESUMO

Master transcription factors have the ability to direct and reverse cellular identities, and consequently their genes must be subject to particular transcriptional control. However, it is unclear which molecular processes are responsible for impeding their activation and safeguarding cellular identities. Here we show that the targeting of dCas9-VP64 to the promoter of the master transcription factor Sox1 results in strong transcript and protein up-regulation in neural progenitor cells (NPCs). This gene activation restores lost neuronal differentiation potential, which substantiates the role of Sox1 as a master transcription factor. However, despite efficient transactivator binding, major proportions of progenitor cells are unresponsive to the transactivating stimulus. By combining the transactivation domain with epigenome editing we find that among a series of euchromatic processes, the removal of DNA methylation (by dCas9-Tet1) has the highest potential to increase the proportion of cells activating foreign master transcription factors and thus breaking down cell identity barriers.


Assuntos
Diferenciação Celular/genética , Reprogramação Celular/genética , Epigênese Genética , Células-Tronco Neurais/fisiologia , Fatores de Transcrição SOXB1/metabolismo , Animais , Sistemas CRISPR-Cas/genética , Linhagem Celular , Metilação de DNA/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Edição de Genes/métodos , Regulação da Expressão Gênica , Camundongos , Neuroglia/citologia , Neuroglia/fisiologia , Regiões Promotoras Genéticas/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , RNA Guia/genética , RNA Guia/metabolismo , Fatores de Transcrição SOXB1/genética , Transcrição Genética/genética
20.
Transl Res ; 209: 90-104, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31085163

RESUMO

Chronic kidney disease (CKD) affects more than 20 million people in the United States and the global burden of this disorder is increasing. Many affected individuals will progress to end stage kidney disease necessitating dialysis or transplantation. CKD is also a major independent contributor to the risk of cardiovascular morbidity and mortality. Tubulointerstitial fibrosis is a final common pathway for most causes of progressive CKD. Currently, there are no clinically available therapies targeting fibrosis that can slow the decline in kidney function. Although it has long been known that TGF-ß signaling is a critical mediator of kidney fibrosis, translating this knowledge to the clinic has been challenging. In this review, we highlight some recent insights into the mechanisms of TGF-ß signaling that target activation of this cytokine at the site of injury or selectively inhibit pro-fibrotic gene expression. Molecules directed at these targets hold the promise of attaining therapeutic efficacy while limiting toxicity seen with global inhibition of TGF-ß. Kidney injury has profound epigenetic effects leading to altered expression of more than a thousand genes. We discuss how drugs targeting epigenetic modifications, some of which are in use for cancer therapy, have the potential to reprogram gene regulatory networks to favor adaptive repair and prevent fibrosis. The lack of reliable biomarkers of kidney fibrosis is a major limitation in designing clinical trials for testing CKD treatments. We conclude by reviewing recent advances in fibrosis biomarker development.


Assuntos
Rim/metabolismo , Rim/patologia , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Metilação de DNA/genética , Fibrose , Humanos , Modelos Biológicos
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