Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 236
Filtrar
1.
Sci Rep ; 10(1): 12239, 2020 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-32699220

RESUMO

Lithium (Li) is the cornerstone maintenance treatment for bipolar disorders (BD), but response rates are highly variable. To date, no clinical or biological marker is available to reliably define eligibility criteria for a maintenance treatment with Li. We examined whether the prophylactic response to Li (assessed retrospectively) is associated with distinct blood DNA methylation profiles. Bisulfite-treated total blood DNA samples from individuals with BD type 1 (15 excellent-responders (LiERs) versus 11 non-responders (LiNRs)) were used for targeted enrichment of CpG rich genomic regions followed by high-resolution next-generation sequencing to identify differentially methylated regions (DMRs). After controlling for potential confounders we identified 111 DMRs that significantly differ between LiERs and LiNRs with a significant enrichment in neuronal cell components. Logistic regression and receiver operating curves identified a combination of 7 DMRs with a good discriminatory power for response to Li (Area Under the Curve 0.806). Annotated genes associated with these DMRs include Eukaryotic Translation Initiation Factor 2B Subunit Epsilon (EIF2B5), Von Willebrand Factor A Domain Containing 5B2 (VWA5B2), Ral GTPase Activating Protein Catalytic Alpha Subunit 1 (RALGAPA1). Although preliminary and deserving replication, these results suggest that biomarkers of response to Li may be identified through peripheral epigenetic measures.


Assuntos
Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/genética , Metilação de DNA/efeitos dos fármacos , Metilação de DNA/genética , Lítio/uso terapêutico , Biomarcadores/metabolismo , Ilhas de CpG/efeitos dos fármacos , Ilhas de CpG/genética , DNA/genética , Epigênese Genética/efeitos dos fármacos , Epigênese Genética/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
2.
Am J Physiol Cell Physiol ; 319(2): C268-C276, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32459505

RESUMO

DNA methylation, a critical epigenetic mechanism, plays an important role in governing gene expressions during biological processes such as aging, which is well known to be accelerated in hyperglycemia (diabetes). In the present study, we investigated the effects of glucose on whole genome DNA methylation in small [human retinal microvascular endothelial cells (HRECs)] and large [human umbilical vein endothelial cells (HUVECs)] vessel endothelial cell (EC) lines exposed to basal or high glucose-containing media for variable lengths of time. Using the Infinium EPIC array, we obtained 773,133 CpG sites (probes) for analysis. Unsupervised clustering of the top 5% probes identified four distinct clusters within EC groups, with significant methylation differences attributed to EC types and the duration of cell culture rather than glucose stimuli alone. When comparing the ECs incubated for 2 days versus 7 days, hierarchical clustering analyses [methylation change >10% and false discovery rate (FDR) <0.05] identified 17,354 and 128 differentially methylated CpGs for HUVECs and HRECs, respectively. Predominant DNA hypermethylation was associated with the length of culture and was enriched for gene enhancer elements and regions surrounding CpG shores and shelves. We identified 88 differentially methylated regions (DMRs) for HUVECs and 8 DMRs for HRECs (all FDR <0.05). Pathway enrichment analyses of DMRs highlighted involvement of regulators of embryonic development (i.e., HOX genes) and cellular differentiation [transforming growth factor-ß (TGF-ß) family members]. Collectively, our findings suggest that DNA methylation is a complex process that involves tightly coordinated, cell-specific mechanisms. Such changes in methylation overlap genes critical for cellular differentiation and embryonic development.


Assuntos
Envelhecimento/genética , Ilhas de CpG/genética , Metilação de DNA/genética , Células Endoteliais/metabolismo , Envelhecimento/patologia , Ilhas de CpG/efeitos dos fármacos , DNA/genética , Metilação de DNA/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Epigênese Genética , Regulação da Expressão Gênica/efeitos dos fármacos , Genes Homeobox/genética , Genoma Humano/genética , Glucose/farmacologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Regiões Promotoras Genéticas/efeitos dos fármacos
3.
Chem Biol Interact ; 321: 109025, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-32135139

RESUMO

Epigenetic regulation is one of the driving forces in the process of carcinogenesis. Corosolic acid (CA); triterpenoid abundantly found in Lagerstroemia speciosa L. is known to modulate various cellular process including cellular oxidative stress and signaling kinases in various diseases, including skin cancer. Genetic mutations in early stages of skin cancer are well-documented, the epigenetic alterations remain elusive. In the present study, we identified the transcriptomic gene expression changes with RNAseq and genome-wide DNA CpG methylation changes with DNA methylseq to profile the early stage transcriptomic and epigenomic changes using tumor promoter TPA-mediated mouse epidermal epithelial JB6 P+ cells. JB6 P+ cells were treated with TPA and Corosolic acid by 7.5uM optimized by MTS assay. Differentiated expressed genes (DEGs) and Differentially methylated genes (DMRs) were analyzed by R software. Ingenuity Pathway Analysis (IPA) was employed to understand the differential regulation of specific pathways. Novel TPA induced differentially overexpressed genes like tumor promoter Prl2c2, small prolin rich protein (Sprr2h) was reported which was downregulated by corosolic acid treatment. Several cancer related pathways were identified by Ingenuity Pathways Analysis (IPA) including p53, Erk, TGF beta signaling pathways. Moreover, differentially methylated regions (DMRs) in genes like Dusp22 (Dual specificity protein phosphatase 22), Rassf (tumor suppressor gene family, Ras association domain family) in JB6 P+ cells were uncovered which are altered by TPA and are reversed by CA treatment. Interestingly, genes like CDK1 (Cyclin-dependent kinases 1) and RASSF2 (Ras association domain family member 2) observed to be differentially methylated and expressed which was further modulated by corosolic acid treatment, validated by qPCR. Given study indicated gene expression changes to DNA CpG methylation epigenomic changes modulated various molecular pathways in TPA-induced JB6 cells and revealed that CA can potentially reverse these changes which deciphering novel molecular targets for future prevention of early stages of skin cancer studies in human.


Assuntos
Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/metabolismo , Metilação de DNA/efeitos dos fármacos , Células Epidérmicas/efeitos dos fármacos , Células Epidérmicas/metabolismo , Triterpenos/farmacologia , Animais , Carcinógenos/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Ilhas de CpG/efeitos dos fármacos , Células Epidérmicas/patologia , Epigênese Genética/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Camundongos , Compostos Fitoquímicos/farmacologia , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/metabolismo , Acetato de Tetradecanoilforbol/toxicidade , Transcriptoma/efeitos dos fármacos
4.
Acta Biochim Pol ; 66(4): 619-625, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31826047

RESUMO

The CD146 (also known as MCAM, MUC-18, Mel-CAM) was initially reported in 1987, as a protein crucial for the invasiveness of malignant melanoma. Recently, it has been confirmed that CD146 has been involved in progression and poor overall survival of many cancers including breast cancer. Importantly, in independent studies, CD146 was reported to be a trigger of epithelial to mesenchymal transition in breast cancer cells. The goal of our current study was to verify the potential involvement of epigenetic mechanism behind the regulation of CD146 expression in breast cancer cells, as it has been previously reported in prostate cancer. First, we analysed the response of breast cancer cell lines, differing in the initial CD146 mRNA and protein content, to epigenetic modifier, 5-aza-2-deoxycytidine, and subsequently the methylation status of CD146 gene promoter was investigated, using direct bisulfite sequencing. We observed that treatment with demethylating agent led to induction of CD146 expression in all analysed breast cancer cell lines, both at mRNA and protein level, what was accompanied by increased expression of selected mesenchymal markers. Importantly, CD146 gene promoter analysis showed aberrant CpG island methylation in 2 out of 3 studied breast cancer cells lines, indicating epigenetic regulation of CD146 gene expression. In conclusion, our study revealed, for the first time, that aberrant methylation maybe involved in expression control of CD146, a very potent EMT inducer in breast cancer cells. Altogether, the data obtained may provide the basis for novel therapies as well as diagnostic approaches enabling sensitive and very accurate detection of breast cancer cells.


Assuntos
Neoplasias da Mama/genética , Metilação de DNA/efeitos dos fármacos , Decitabina/farmacologia , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Antígeno CD146/genética , Ilhas de CpG/efeitos dos fármacos , Progressão da Doença , Epigênese Genética/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Regiões Promotoras Genéticas/efeitos dos fármacos , Análise de Sequência de DNA
5.
Clin Epigenetics ; 11(1): 198, 2019 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-31878957

RESUMO

BACKGROUND: Metabolic side effects induced by psychotropic drugs represent a major health issue in psychiatry. CREB-regulated transcription coactivator 1 (CRTC1) gene plays a major role in the regulation of energy homeostasis and epigenetic mechanisms may explain its association with obesity features previously described in psychiatric patients. This prospective study included 78 patients receiving psychotropic drugs that induce metabolic disturbances, with weight and other metabolic parameters monitored regularly. Methylation levels in 76 CRTC1 probes were assessed before and after 1 month of psychotropic treatment in blood samples. RESULTS: Significant methylation changes were observed in three CRTC1 CpG sites (i.e., cg07015183, cg12034943, and cg 17006757) in patients with early and important weight gain (i.e., equal or higher than 5% after 1 month; FDR p value = 0.02). Multivariable models showed that methylation decrease in cg12034943 was more important in patients with early weight gain (≥ 5%) than in those who did not gain weight (p = 0.01). Further analyses combining genetic and methylation data showed that cg12034943 was significantly associated with early weight gain in patients carrying the G allele of rs4808844A>G (p = 0.03), a SNP associated with this methylation site (p = 0.03). CONCLUSIONS: These findings give new insights on psychotropic-induced weight gain and underline the need of future larger prospective epigenetic studies to better understand the complex pathways involved in psychotropic-induced metabolic side effects.


Assuntos
Metilação de DNA/efeitos dos fármacos , Obesidade/genética , Polimorfismo de Nucleotídeo Único , Psicotrópicos/efeitos adversos , Fatores de Transcrição/genética , Ganho de Peso/genética , Adulto , Idade de Início , Alelos , Estudos de Casos e Controles , Ilhas de CpG/efeitos dos fármacos , Epigênese Genética , Feminino , Estudos de Associação Genética , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Obesidade/induzido quimicamente , Estudos Prospectivos , Psicotrópicos/farmacologia
6.
Clin Epigenetics ; 11(1): 143, 2019 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-31623675

RESUMO

BACKGROUND: Patients with haematological malignancies are often vitamin C deficient, and vitamin C is essential for the TET-induced conversion of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC), the first step in active DNA demethylation. Here, we investigate whether oral vitamin C supplementation can correct vitamin C deficiency and affect the 5hmC/5mC ratio in patients with myeloid cancers treated with DNA methyltransferase inhibitors (DNMTis). RESULTS: We conducted a randomized, double-blinded, placebo-controlled pilot trial (NCT02877277) in Danish patients with myeloid cancers performed during 3 cycles of DNMTi-treatment (5-azacytidine, 100 mg/m2/d for 5 days in 28-day cycles) supplemented by oral dose of 500 mg vitamin C (n = 10) or placebo (n = 10) daily during the last 2 cycles. Fourteen patients (70%) were deficient in plasma vitamin C (< 23 µM) and four of the remaining six patients were taking vitamin supplements at inclusion. Global DNA methylation was significantly higher in patients with severe vitamin C deficiency (< 11.4 µM; 4.997 vs 4.656% 5mC relative to deoxyguanosine, 95% CI [0.126, 0.556], P = 0.004). Oral supplementation restored plasma vitamin C levels to the normal range in all patients in the vitamin C arm (mean increase 34.85 ± 7.94 µM, P = 0.0004). We show for the first time that global 5hmC/5mC levels were significantly increased in mononuclear myeloid cells from patients receiving oral vitamin C compared to placebo (0.037% vs - 0.029%, 95% CI [- 0.129, - 0.003], P = 0.041). CONCLUSIONS: Normalization of plasma vitamin C by oral supplementation leads to an increase in the 5hmC/5mC ratio compared to placebo-treated patients and may enhance the biological effects of DNMTis. The clinical efficacy of oral vitamin C supplementation to DNMTis should be investigated in a large randomized, placebo-controlled clinical trial. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02877277 . Registered on 9 August 2016, retrospectively registered.


Assuntos
Ácido Ascórbico/administração & dosagem , Azacitidina/administração & dosagem , Metilação de DNA/efeitos dos fármacos , Leucemia Mieloide/terapia , Síndromes Mielodisplásicas/terapia , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Ácido Ascórbico/sangue , Ácido Ascórbico/farmacologia , Azacitidina/farmacologia , Ilhas de CpG/efeitos dos fármacos , Dinamarca , Método Duplo-Cego , Epigênese Genética/efeitos dos fármacos , Feminino , Humanos , Leucemia Mieloide/sangue , Leucemia Mieloide/genética , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/sangue , Síndromes Mielodisplásicas/genética , Projetos Piloto
7.
Clin Epigenetics ; 11(1): 138, 2019 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-31601247

RESUMO

BACKGROUND: Bisphenol A (BPA), an estrogen-like endocrine disruptor used in plastics, has been associated with development and promotion of breast cancer, so plastic manufacturers shifted towards less-studied analogs, BPF and BPS. Studying the associated DNA methylome-wide mechanisms of these derivatives is timely, particularly in comparison with BPA. METHODS: We assessed proliferation, cell cycle, and migration of breast cancer cells (estrogen receptor (ER)-positive: MCF-7 and ER-negative: MDA-MB-231) treated with BPF and BPS ± estrogen receptor inhibitor (ERI) in comparison to BPA ± ERI. RNA expression and activity of DNA (de)methylation enzymes and LINE-1 methylation were quantified. DNA methylome-wide analysis was evaluated in bisphenol-exposed cells and compared to clinical breast cancer data. RESULTS: The three bisphenols caused ER-dependent increased proliferation and migration of MCF-7 but not MDA-MB-231 cells, with BPS being 10 times less potent than BPA and BPF. Although they have similar chemical structures, the three bisphenols induced differential DNA methylation alterations at several genomic clusters of or single CpG sites, with the majority of these being ER-dependent. At equipotent doses, BPA had the strongest effect on the methylome, followed by BPS then BPF. No pathways were enriched for BPF while BPA- and BPS-induced methylome alterations were enriched in focal adhesion, cGMP-PKG, and cancer pathways, which were also dysregulated in methylome-wide alterations comparing ER-positive breast cancer samples to adjacent normal tissues. CONCLUSIONS: The three bisphenols have important epigenetic effects in breast cell lines, with those of BPA and BPS overlapping with cancer-related pathways in clinical breast cancer models. Hence, further investigation of their safety is warranted.


Assuntos
Compostos Benzidrílicos/farmacologia , Neoplasias da Mama/genética , Metilação de DNA/efeitos dos fármacos , Redes Reguladoras de Genes/efeitos dos fármacos , Fenóis/farmacologia , Receptores Estrogênicos/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ilhas de CpG/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Feminino , Adesões Focais/efeitos dos fármacos , Fulvestranto/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Elementos Nucleotídeos Longos e Dispersos/efeitos dos fármacos , Células MCF-7 , Receptores Estrogênicos/antagonistas & inibidores
8.
Epigenetics ; 14(10): 989-1002, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31208284

RESUMO

Many cancer therapies operate by inducing double-strand breaks (DSBs) in cancer cells, however treatment-resistant cells rapidly initiate mechanisms to repair damage enabling survival. While the DNA repair mechanisms responsible for cancer cell survival following DNA damaging treatments are becoming better understood, less is known about the role of the epigenome in this process. Using prostate cancer cell lines with differing sensitivities to radiation treatment, we analysed the DNA methylation profiles prior to and following a single dose of radiotherapy (RT) using the Illumina Infinium HumanMethylation450 BeadChip platform. DSB formation and repair, in the absence and presence of the DNA hypomethylating agent, 5-azacytidine (5-AzaC), were also investigated using γH2A.X immunofluorescence staining. Here we demonstrate that DNA methylation is generally stable following a single dose of RT; however, a small number of CpG sites are stably altered up to 14 d following exposure. While the radioresistant and radiosensitive cells displayed distinct basal DNA methylation profiles, their susceptibility to DNA damage appeared similar demonstrating that basal DNA methylation has a limited influence on DSB induction at the regions examined. Recovery from DSB induction was also similar between these cells. Treatment with 5-AzaC did not sensitize resistant cells to DNA damage, but rather delayed recruitment of phosphorylated BRCA1 (S1423) and repair of DSBs. These results highlight that stable epigenetic changes are possible following a single dose of RT and may have significant clinical implications for cancer treatment involving recurrent or fractionated dosing regimens.


Assuntos
Azacitidina/farmacologia , Dano ao DNA , Metilação de DNA , Neoplasias da Próstata/genética , Proteína BRCA1/metabolismo , Linhagem Celular Tumoral , Ilhas de CpG/efeitos dos fármacos , Ilhas de CpG/efeitos da radiação , Metilação de DNA/efeitos dos fármacos , Metilação de DNA/efeitos da radiação , Epigênese Genética/efeitos dos fármacos , Epigênese Genética/efeitos da radiação , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Células PC-3 , Fosforilação , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/radioterapia , Tolerância a Radiação , Análise de Sequência de DNA
9.
Environ Health Perspect ; 127(5): 57011, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31135185

RESUMO

BACKGROUND: Arsenic exposure affects [Formula: see text] people worldwide, including [Formula: see text] in Bangladesh. Arsenic exposure increases the risk of cancer and other chronic diseases, and one potential mechanism of arsenic toxicity is epigenetic dysregulation. OBJECTIVE: We assessed associations between arsenic exposure and genome-wide DNA methylation measured at baseline among 396 Bangladeshi adults participating in the Health Effects of Arsenic Longitudinal Study (HEALS) who were exposed by drinking naturally contaminated well water. METHODS: Methylation in whole blood DNA was measured at [Formula: see text] using the Illumina InfiniumMethylationEPIC (EPIC) array. To assess associations between arsenic exposure and CpG methylation, we used linear regression models adjusted for covariates and surrogate variables (SVs) (capturing unknown technical and biologic factors). We attempted replication and conducted a meta-analysis using an independent dataset of [Formula: see text] from 400 Bangladeshi individuals with arsenical skin lesions. RESULTS: We identified 34 CpGs associated with [Formula: see text] creatinine-adjusted urinary arsenic [[Formula: see text]]. Sixteen of these CpGs annotated to the [Formula: see text] array, and 10 associations were replicated ([Formula: see text]). The top two CpGs annotated upstream of the ABR gene (cg01912040, cg10003262 ). All urinary arsenic-associated CpGs were also associated with arsenic concentration measured in drinking water ([Formula: see text]). Meta-analysis ([Formula: see text] samples) identified 221 urinary arsenic-associated CpGs ([Formula: see text]). The arsenic-associated CpGs from the meta-analysis were enriched in non-CpG islands and shores ([Formula: see text]) and depleted in promoter regions ([Formula: see text]). Among the arsenic-associated CpGs ([Formula: see text]), we observed significant enrichment of genes annotating to the reactive oxygen species pathway, inflammatory response, and tumor necrosis factor [Formula: see text] ([Formula: see text]) signaling via nuclear factor kappa-B ([Formula: see text]) hallmarks ([Formula: see text]). CONCLUSIONS: The novel and replicable associations between arsenic exposure and DNA methylation at specific CpGs observed in this work suggest that epigenetic alterations should be further investigated as potential mediators in arsenic toxicity and as biomarkers of exposure and effect in exposed populations. https://doi.org/10.1289/EHP3849.


Assuntos
Arsênico/urina , Metilação de DNA/efeitos dos fármacos , Água Potável/análise , Exposição Ambiental/análise , Poluentes Químicos da Água/urina , Adulto , Idoso , Bangladesh , Estudos de Coortes , Ilhas de CpG/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
Clin Epigenetics ; 11(1): 76, 2019 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-31088577

RESUMO

OBJECTIVE: To identify novel epigenetic signatures that could provide predictive information that is complementary to promoter methylation status of the O-6-methylguanine-DNA methyltransferase (MGMT) gene for predicting temozolomide (TMZ) response, among glioblastomas (GBMs) without glioma-CpGs island methylator phenotype (G-CIMP) METHODS: Different cohorts of primary non-G-CIMP GBMs with genome-wide DNA methylation microarray data were included for discovery and validation of a multimarker signature, combined using a RISK score model. Different statistical analyses and functional experiments were performed for clinical and biological validation. RESULTS: By employing discovery cohorts with radiotherapy (RT) and TMZ versus RT alone and a strict multistep selection strategy, we identified seven CpGs, each of which was significantly correlated with overall survival (OS) of non-G-CIMP GBMs with RT/TMZ, independent of age, MGMT promoter methylation status, and other identified CpGs. A RISK score signature of the 7 CpGs was developed and validated to distinguish non-G-CIMP GBMs with differential survival outcomes to RT/TMZ, but not to RT alone. The interaction analyses also showed differential outcomes to RT/TMZ versus RT alone within the RISK score-based subgroups. The signature could also improve the risk classification by age and MGMT promoter methylation status. Functional experiments showed that HSBP2 appeared to be epigenetically regulated by one identified CpG and was associated with TMZ resistance, but it was not associated with cell proliferation or apoptosis in GBM cell lines. The predictive value of the single CpG methylation of HSBP2 by pyrosequencing was observed in a local cohort of isocitrate dehydrogenase 1 (IDH1) R132H wild-type GBMs. CONCLUSIONS: This novel epigenetic signature might be a promising predictive (but not a general prognostic) biomarker and be helpful for refining the MGMT-based guiding approach to TMZ usage in non-G-CIMP GBMs.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Glioblastoma/tratamento farmacológico , Proteínas de Choque Térmico HSP27/genética , Temozolomida/uso terapêutico , Antineoplásicos Alquilantes/farmacologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/radioterapia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Ilhas de CpG/efeitos dos fármacos , Ilhas de CpG/efeitos da radiação , Metilação de DNA/efeitos dos fármacos , Metilação de DNA/efeitos da radiação , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Epigênese Genética/efeitos dos fármacos , Epigênese Genética/efeitos da radiação , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Glioblastoma/genética , Glioblastoma/radioterapia , Humanos , Isocitrato Desidrogenase/genética , Masculino , Análise de Sobrevida , Temozolomida/farmacologia , Resultado do Tratamento , Proteínas Supressoras de Tumor/genética
11.
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
12.
Am J Epidemiol ; 188(6): 1055-1065, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30938765

RESUMO

The biological mechanisms driving associations between alcohol consumption and chronic diseases might include epigenetic modification of DNA methylation. We explored the hypothesis that alcohol consumption is associated with methylation in an epigenome-wide association study of blood and normal breast tissue DNA. Infinium HumanMethylation450 BeadChip (Illumina Inc., San Diego, California) array data on blood DNA methylation was examined in a discovery set of 2,878 non-Hispanic white women from the Sister Study (United States, 2004-2015) who provided detailed questionnaire information on lifetime alcohol use. Robust linear regression modeling was used to identify significant associations (false discovery rate of Q < 0.05) between the number of alcoholic drinks per week and DNA methylation at 5,458 cytosine-phosphate-guanine (CpG) sites. Associations were replicated (P < 0.05) for 677 CpGs in an independent set of 187 blood DNA samples from the Sister Study and for 628 CpGs in an independent set of 171 normal breast DNA samples; 1,207 CpGs were replicated in either blood or normal breast, with 98 CpGs replicated in both tissues. Individual gene effects were notable for phosphoglycerate dehydrogenase (PGHDH), peptidyl-prolyl cis-trans isomerase (PPIF), solute carrier 15 (SLC15), solute carrier family 43 member 1 (SLC43A1), and solute carrier family 7 member 11 (SLC7A11). We also found that high alcohol consumption was associated with significantly lower global methylation as measured by the average of CpGs on the entire array.


Assuntos
Consumo de Bebidas Alcoólicas/epidemiologia , Ilhas de CpG/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Epigenoma/efeitos dos fármacos , Adulto , Índice de Massa Corporal , Feminino , Humanos , Estilo de Vida , Pessoa de Meia-Idade , Estudos Prospectivos , Irmãos , Estados Unidos
13.
Environ Mol Mutagen ; 60(7): 576-587, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30848857

RESUMO

In vitro cell transformation assays (CTA) have been proposed as a method to identify possible nongenotoxic carcinogens. However, the current protocols do not provide information on the mechanism of action of the test articles. In this study, we combined an in vitro Bhas 42 CTA and sequencing-based DNA methylation profiling analysis to elucidate the carcinogenic mechanism associated with nongenotoxic carcinogens. Three nongenotoxic carcinogens were evaluated: cadmium chloride, methyl carbamate, and lithocholic acid. Methylation profiles were generated for the two nongenotoxic carcinogens (cadmium chloride and lithocholic acid) that were positive in Bhas 42 CTA. Methyl carbamate did not exhibit any promoter activity. Approximately 9.8% of all differentially methylated regions (DMRs) identified in cadmium chloride-induced transformed foci overlapped with DMRs in lithocholic acid-induced transformed foci. Interestingly, overlapping DMRs showed more hypermethylation than individual DMRs. In addition, the DMRs in CpG island elements common to both nongenotoxic carcinogens showed considerably more bias toward hypermethylated DMRs than those unique to either cadmium chloride or lithocholic acid. Pathway enrichment analysis revealed that genes harboring hypermethylated DMRs were significantly enriched in Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways including pathways in cancer, basal cell carcinoma, and Wnt signaling. The genes harboring hypomethylated DMRs were significantly related to mRNA surveillance pathway, RNA transport, and autophagy. Taken together, our preliminary results on genome-wide methylation analysis of cell clones from nongenotoxic carcinogen-induced foci could be exploited for CTAs improvement, but further research will be required to standardize and assess the specificity and sensitivity of this combined approach. Environ. Mol. Mutagen. 2019. © 2019 Wiley Periodicals, Inc.


Assuntos
Carcinógenos/toxicidade , Transformação Celular Neoplásica/induzido quimicamente , Metilação de DNA/efeitos dos fármacos , Metilação de DNA/genética , Genoma/efeitos dos fármacos , Genoma/genética , Animais , Células 3T3 BALB , Ilhas de CpG/efeitos dos fármacos , Ilhas de CpG/genética , DNA/efeitos dos fármacos , DNA/genética , Estudo de Associação Genômica Ampla/métodos , Camundongos , Mutagênicos/toxicidade , Neoplasias/induzido quimicamente , Neoplasias/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
14.
Clin Epigenetics ; 11(1): 45, 2019 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-30867049

RESUMO

BACKGROUND: Little is known about the effects of chemotherapeutic drugs on DNA methylation status of leukocytes, which may be predictive of treatment benefits and toxicities. Based on a prospective national study, we characterize the changes in leukocyte DNA methylome from pre- to post-chemotherapy (approximately 4 months apart) in 93 patients treated for early stage breast cancer and 48 matched non-cancer controls. We further examined significant methylation changes with perceived cognitive impairment, a clinically significant problem related to cancer and chemotherapy. RESULTS: Approximately 4.2% of the CpG sites measured using the Illumina 450K methylation array underwent significant changes after chemotherapy (p < 1e-7), in comparison to a stable DNA methylome in controls. Post-chemotherapy, the estimated relative proportions of B cells and CD4+ T cells were decreased by a median of 100% and 39%, respectively, whereas the proportion of monocytes was increased by a median of 91%. After controlling for leukocyte composition, 568 CpGs from 460 genes were still significantly altered following chemotherapy. With additional adjustment for chemotherapy regimen, cumulative infusions, growth factors, and steroids, changes in four CpGs remained significant, including cg16936953 in VMP1/MIR21, cg01252023 in CORO1B, cg11859398 in SDK1, and cg19956914 in SUMF2. The most significant CpG, cg16936953, was also associated with cognitive decline in breast cancer patients. CONCLUSIONS: Chemotherapy profoundly alters the composition and DNA methylation landscape of leukocytes in breast cancer patients. Our results shed light on the epigenetic response of circulating immune cell populations to cytotoxic chemotherapeutic drugs and provide possible epigenetic links to the degeneration of cognitive function associated with chemotherapy.


Assuntos
Antineoplásicos/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Cognição/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Leucócitos/química , Antineoplásicos/farmacologia , Neoplasias da Mama/sangue , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Ilhas de CpG/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Feminino , Humanos , Leucócitos/efeitos dos fármacos , Estadiamento de Neoplasias , Estudos Prospectivos , Resultado do Tratamento
15.
Psychiatry Clin Neurosci ; 73(6): 323-330, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30821055

RESUMO

AIM: Glucocorticoids play a major role in regulating the stress response, and an imbalance of glucocorticoids has been implicated in stress-related disorders. Within mouse models, CpGs across the genome have been shown to be differentially methylated in response to glucocorticoid treatment, and using the Infinium 27K array, it was shown that humans given synthetic glucocorticoids had DNA methylation (DNAm) changes in blood. However, further investigation of the extent to which glucocorticoids affect DNAm across a larger proportion of the genome is needed. METHODS: Buccal samples were collected before and after synthetic glucocorticoid treatment in the context of a dental procedure. This included 30 tooth extraction surgery patients who received 10 mg of dexamethasone. Genome-wide DNAm was assessed with the Infinium HumanMethylationEPIC array. RESULTS: Five CpGs showed genome-wide significant DNAm changes that were >10%. These differentially methylated CpGs were in or nearest the following genes: ZNF438, KLHDC10, miR-544 or CRABP1, DPH5, and WDFY2. Using previously published datasets of human blood gene expression changes following dexamethasone exposure, a significant proportion of genes with false-discovery-rate-adjusted significant CpGs were also differentially expressed. A pathway analysis of the genes with false-discovery-rate-adjusted significant CpGs revealed significant enrichment of olfactory transduction, pentose and glucuronate interconversions, ascorbate and aldarate metabolism, and steroid hormone biosynthesis pathways. CONCLUSION: High-dose synthetic glucocorticoid administration in the setting of a dental procedure was significantly associated with DNAm changes within buccal samples. These findings are consistent with prior findings of an influence of glucocorticoids on DNAm in humans.


Assuntos
Ilhas de CpG/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Dexametasona/farmacologia , Expressão Gênica/efeitos dos fármacos , Genoma Humano/efeitos dos fármacos , Glucocorticoides/farmacologia , Adulto , Dexametasona/administração & dosagem , Feminino , Glucocorticoides/administração & dosagem , Humanos , Masculino , Mucosa Bucal , Procedimentos Cirúrgicos Bucais , Adulto Jovem
16.
Nucleic Acid Ther ; 29(4): 224-229, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30835633

RESUMO

Single-strand oligodeoxynucleotides (ODNs) containing unmethylated cytosine-phosphate-guanine (CpG) are recognized by the toll-like receptor 9, a component of the innate immunity. Therefore, they could act as immunotherapeutic agents. Chemically modified CpG ODNs containing a phosphorothioate backbone instead of phosphodiester (PD) were developed as immunotherapeutic agents resistant to nuclease degradation. However, they cause adverse side effects, and so there is a necessity to generate novel CpG ODNs. In the present study, we designed a nuclease-resistant nonmodified CpG ODN that forms G-quadruplex structures. G-quadruplex formation in CpG ODNs increased nuclease resistance and cellular uptake. The CpG ODNs designed in this study induced interleukin-6 production in a human B lymphocyte cell line and human peripheral blood mononuclear cells. These results indicate that G-quadruplex formation can be used to increase the immunostimulatory activity of CpG ODNs having a natural PD backbone.


Assuntos
Quadruplex G , Leucócitos Mononucleares/imunologia , Oligonucleotídeos Antissenso/genética , Adjuvantes Imunológicos/genética , Adjuvantes Imunológicos/farmacologia , Animais , Linhagem Celular , Ilhas de CpG/efeitos dos fármacos , Humanos , Fatores Imunológicos/genética , Leucócitos Mononucleares/efeitos dos fármacos , Conformação de Ácido Nucleico/efeitos dos fármacos , Oligonucleotídeos Antissenso/química , Fosfatos/química , Fosfatos/metabolismo
17.
Chem Res Toxicol ; 32(3): 493-499, 2019 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-30746931

RESUMO

Prenatal exposure to inorganic arsenic (iAs) has been associated with adverse developmental and reproductive outcomes. These outcomes may be tied to altered functionality of nuclear transcription factors such as the glucocorticoid receptor (GR) in the placenta and associated gene expression. The GR pathway is integral for proper fetal and placental development, and perturbations in this pathway may underlie observed associations between prenatal iAs exposure and adverse birth outcomes. We therefore set out to investigate whether iAs modulates the GR signaling pathway in placental cells. JEG-3 trophoblasts were exposed to environmentally-relevant doses of iAs, and mRNA expression assessed. To examine the links between iAs exposure, the GR signaling pathway, and epigenetic modification, DNA methylation levels were also quantified. Treatment with iAs altered the expression of 12 GR-genes that play a role in fetal and placental development. Furthermore, at a gene-specific level, mRNA abundance was associated with changes in DNA methylation patterning in JEG-3 cells, suggesting that the effects of iAs are mediated by epigenetic mechanisms. The identified target genes have been associated with prenatal iAs exposure, placental physiology, and fetal development. This study provides further evidence for iAs as an endocrine disruptor and provides insight as to the mechanisms by which prenatal iAs exposure may induce adverse birth outcomes.


Assuntos
Arsênico/toxicidade , Ilhas de CpG/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Disruptores Endócrinos/toxicidade , Placenta/citologia , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Feminino , Humanos , Gravidez , Células Tumorais Cultivadas
18.
Neurobiol Learn Mem ; 159: 6-15, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30731235

RESUMO

Enhancement of synaptic plasticity through changes in neuronal gene expression is a prerequisite for improved cognitive performance. Moreover, several studies have shown that DNA methylation is able to affect the expression of (e.g. plasticity) genes that are important for several cognitive functions. In this study, the effect of the DNA methyltransferase (DNMT) inhibitor RG108 was assessed on object pattern separation (OPS) task in mice. In addition, its effect on the expression of target genes was monitored. Administration of RG108 before the test led to a short-lasting, dose-dependent increase in pattern separation memory that was not present anymore after 48 h. Furthermore, treatment with RG108 did not enhance long-term memory of the animals when tested after a 24 h inter-trial interval in the same task. At the transcriptomic level, acute treatment with RG108 was accompanied by increased expression of Bdnf1, while expression of Bdnf4, Bdnf9, Gria1 and Hdac2 was not altered within 1 h after treatment. Methylation analysis of 14 loci in the promoter region of Bdnf1 revealed a counterintuitive increase in the levels of DNA methylation at three CpG sites. Taken together, these results indicate that acute administration of RG108 has a short-lasting pro-cognitive effect on object pattern separation that could be explained by increased Bdnf1 expression. The observed increase in Bdnf1 methylation suggests a complex interplay between Bdnf methylation-demethylation that promotes Bdnf1 expression and associated cognitive performance. Considering that impaired pattern separation could constitute the underlying problem of a wide range of mental and cognitive disorders, pharmacological agents including DNA methylation inhibitors that improve pattern separation could be compelling targets for the treatment of these disorders. In that respect, future studies are needed in order to determine the effect of chronic administration of such agents.


Assuntos
DNA (Citosina-5-)-Metiltransferases/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Epigênese Genética/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Memória de Longo Prazo/efeitos dos fármacos , Memória de Curto Prazo/efeitos dos fármacos , Plasticidade Neuronal/efeitos dos fármacos , Ftalimidas/farmacologia , Percepção Espacial/efeitos dos fármacos , Triptofano/análogos & derivados , Animais , Comportamento Animal/efeitos dos fármacos , Ilhas de CpG/efeitos dos fármacos , Comportamento Exploratório/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Camundongos , Vírus Miúdo do Camundongo , Regiões Promotoras Genéticas/efeitos dos fármacos , Triptofano/farmacologia
19.
Diabetes Res Clin Pract ; 148: 189-199, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30641161

RESUMO

AIMS: Epigenetic mechanisms regulate gene expression and may influence the pathogenesis of type 2 diabetes through the loss of insulin sensitivity. The aims of this study were to measure variation in DNA methylation at the type 2 diabetes locus KCNQ1 and assess its relationship with metabolic measures and with genotype. METHODS: DNA methylation from whole blood DNA was quantified using pyrosequencing at 5 CpG sites at the KCNQ1 locus in 510 individuals without diabetes from the 'Relationship between Insulin Sensitivity and Cardiovascular disease' (RISC) cohort. Genotype data was analysed at the same locus in 1119 individuals in the same cohort. Insulin sensitivity was assessed by euglycaemic-hyperinsulinaemic clamp. RESULTS: DNA methylation at the KCNQ1 locus was inversely associated with insulin sensitivity and serum adiponectin. This association was driven by a methylation-altering Single Nucleotide Polymorphism (SNP) (rs231840) which ablated a methylation site and reduced methylation levels. A second SNP (rs231357), in weak Linkage Disequilibrium (LD) with rs231840, was also associated with insulin sensitivity and DNA methylation. These SNPs have not been previously reported to be associated with type 2 diabetes risk or insulin sensitivity. CONCLUSION: Evidence indicates that genetic and epigenetic determinants at the KCNQ1 locus influence insulin sensitivity.


Assuntos
Ilhas de CpG/efeitos dos fármacos , Ilhas de CpG/genética , Metilação de DNA , Diabetes Mellitus Tipo 2/genética , Loci Gênicos/genética , Resistência à Insulina/genética , Canal de Potássio KCNQ1/genética , Adulto , Estudos de Coortes , Análise Mutacional de DNA/métodos , Epigênese Genética/fisiologia , Feminino , Estudos de Associação Genética , Genótipo , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
20.
J Cell Biochem ; 120(1): 809-820, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30145810

RESUMO

Curcumin, the active component of the spice turmeric, induce global DNA hypomethylation as it has been shown to inhibit DNA methyltransferases. It promotes cell death in cancer cells by arresting in the G1 phase. It was explained to cause increased expression of cell cycle regulator, p21 (WAF1/Cip1); however, the mechanism remains not clear. The p21 promoter harvests a CpG island (CGI) in the proximal region enriched with CG dinucleotide clusters with Kruppel-like factor 4 (KLF4) transcription factor binding site. We probed the p21 promoter CGI (spanning from -135 to +12, respective to the transcription start site) to detect alterations in cytosine methylation level in response to curcumin exposure in four different human cancer cell lines: A431, A549, MCF7, and HeLa. We observed curcumin (20 µM) treatment significantly increased the expression of p21, and the promoter CGI was demethylated in a dose-dependent manner. The curcumin significantly raised the level KLF4 and enhanced the p21 promoter occupancy by KLF4. From our results we hypothesize that curcumin-mediated demethylation of the p21 proximal promoter and increased KLF4 expression as well as its binding to its proximal promoter could serve as a mechanism that could be hypothesized to cause upregulation of p21 in presence of curcumin and thus its therapeutic implications could further be investigated.


Assuntos
Ilhas de CpG/efeitos dos fármacos , Curcumina/farmacologia , Inibidor de Quinase Dependente de Ciclina p21/genética , Metilação de DNA/efeitos dos fármacos , Desmetilação/efeitos dos fármacos , Fatores de Transcrição Kruppel-Like/metabolismo , Extratos Vegetais/farmacologia , Regiões Promotoras Genéticas/efeitos dos fármacos , Células A549 , Sítios de Ligação , Sobrevivência Celular/efeitos dos fármacos , Curcuma/química , DNA (Citosina-5-)-Metiltransferase 1/antagonistas & inibidores , Células HeLa , Humanos , Células MCF-7 , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...