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1.
Ecotoxicol Environ Saf ; 203: 111001, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32888585

RESUMO

Environmental nanomaterials contamination is a great concern for organisms including human. Copper oxide nanoparticles (CuO NPs) are widely used in a huge range of applications which might pose potential risk to organisms. This study investigated the in vivo transgenerational toxicity on development and reproduction with parental CuO NPs exposure in the nematode Caenorhabditis elegans. The results showed that CuO NPs (150 mg/L) significantly reduced the body length of parental C. elegans (P0). Only about 1 mg/L Cu2+ (~0.73%) were detected from 150 mg/L CuO NPs in 0.5X K-medium after 48 h. In transgenerational assays, CuO NPs (150 mg/L) parental exposure significantly induced developmental and reproductive toxicity in non-exposed C. elegans progeny (CuO NPs free) on body length (F1) and brood size (F1 and F2), respectively. In contrast, parental exposure to Cu2+ (1 mg/L) did not cause transgenerational toxicity on growth and reproduction. This suggests that the transgenerational toxicity was mostly attributed to the particulate form of CuO NPs. Moreover, qRT-PCR results showed that the mRNA levels of met-2 and spr-5 genes were significantly decreased at P0 and F1 upon only maternal exposure to CuO NPs (150 mg/L), suggesting the observed transgenerational toxicity was associated with possible epigenetic regulation in C. elegans.


Assuntos
Caenorhabditis elegans/efeitos dos fármacos , Cobre/toxicidade , Epigênese Genética/efeitos dos fármacos , Nanopartículas/toxicidade , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/fisiologia , Feminino , Humanos , Exposição Materna/efeitos adversos , Reprodução/efeitos dos fármacos , Reprodução/genética
2.
Cardiovasc Ther ; 2020: 9397109, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32821285

RESUMO

Chronic systemic inflammation contributes to cardiovascular disease (CVD) and correlates with the abundance of acute phase response (APR) proteins in the liver and plasma. Bromodomain and extraterminal (BET) proteins are epigenetic readers that regulate inflammatory gene transcription. We show that BET inhibition by the small molecule apabetalone reduces APR gene and protein expression in human hepatocytes, mouse models, and plasma from CVD patients. Steady-state expression of serum amyloid P, plasminogen activator inhibitor 1, and ceruloplasmin, APR proteins linked to CVD risk, is reduced by apabetalone in cultured hepatocytes and in humanized mouse liver. In cytokine-stimulated hepatocytes, apabetalone reduces the expression of C-reactive protein (CRP), alpha-2-macroglobulin, and serum amyloid P. The latter two are also reduced by apabetalone in the liver of endotoxemic mice. BET knockdown in vitro also counters cytokine-mediated induction of the CRP gene. Mechanistically, apabetalone reduces the cytokine-driven increase in BRD4 BET occupancy at the CRP promoter, confirming that transcription of CRP is BET-dependent. In patients with stable coronary disease, plasma APR proteins CRP, IL-1 receptor antagonist, and fibrinogen γ decrease after apabetalone treatment versus placebo, resulting in a predicted downregulation of the APR pathway and cytokine targets. We conclude that CRP and components of the APR pathway are regulated by BET proteins and that apabetalone counters chronic cytokine signaling in patients.


Assuntos
Anti-Inflamatórios/farmacologia , Proteína C-Reativa/metabolismo , Doenças Cardiovasculares/tratamento farmacológico , Citocinas/metabolismo , Endotoxemia/tratamento farmacológico , Epigênese Genética/efeitos dos fármacos , Proteínas Nucleares/metabolismo , Quinazolinonas/farmacologia , Fatores de Transcrição/metabolismo , Animais , Sítios de Ligação , Proteína C-Reativa/genética , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/metabolismo , Células Cultivadas , Ceruloplasmina/genética , Ceruloplasmina/metabolismo , Citocinas/genética , Modelos Animais de Doenças , Endotoxemia/genética , Endotoxemia/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Proteínas Nucleares/genética , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Regiões Promotoras Genéticas , Componente Amiloide P Sérico/metabolismo , Transdução de Sinais , Fatores de Transcrição/genética , alfa-Macroglobulinas/genética , alfa-Macroglobulinas/metabolismo
3.
Ecotoxicol Environ Saf ; 202: 110962, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800233

RESUMO

Chronic exposure to fluoride (F) beyond the permissible limit (1.5 ppm) is known to cause detrimental health effects by induction of oxidative stress-mediated DNA damage overpowering the DNA repair machinery. In the present study, we assessed F induced oxidative stress through monitoring biochemical parameters and looked into the effect of chronic F exposure on two crucial DNA repair genes Ogg1 and Rad51 having important role against ROS induced DNA damages. To address this issue, we exposed Swiss albino mice to an environmentally relevant concentration of fluoride (15 ppm NaF) for 8 months. Results revealed histoarchitectural damages in liver, brain, kidney and spleen. Depletion of GSH, increase in lipid peroxidation and catalase activity in liver and brain confirmed the generation of oxidative stress. qRT-PCR result showed that expressions of Ogg1 and Rad51 were altered after F exposure in the affected organs. Promoter hypermethylation was associated with the downregulation of Rad51. F-induced DNA damage and the compromised DNA repair machinery triggered intrinsic pathway of apoptosis in liver and brain. The present study indicates the possible association of epigenetic regulation with F induced neurotoxicity.


Assuntos
Dano ao DNA , DNA Glicosilases/genética , Reparo do DNA , Epigênese Genética/efeitos dos fármacos , Fluoretos/toxicidade , Rad51 Recombinase/genética , Animais , Apoptose/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Relação Dose-Resposta a Droga , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Estresse Oxidativo/efeitos dos fármacos
4.
High Blood Press Cardiovasc Prev ; 27(5): 363-371, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32740853

RESUMO

Epigenetic processing takes centre stage in cardiometabolic diseases (obesity, metabolic syndrome, type 2 diabetes, hypertension), where it participates in adiposity, inflammation, endothelial dysfunction, vascular insulin resistance and atherosclerosis. Epigenetic modifications, defined as heritable changes in gene expression that do not entail mutation in the DNA sequence, are mainly induced by environmental stimuli (stress, pollution, cigarette smoking) and are gaining considerable interest due to their causal role in cardiovascular disease, and their amenability to pharmacological intervention. Importantly, epigenetic modifications acquired during life can be transmitted to the offspring and exert their biological effects across multiple generations. Indeed, such transgenerational transmission of epigenetic signals may contribute to anticipating cardiovascular and metabolic disease phenotypes already in children and young adults. A deeper understanding of environmental factors and their effects on the epigenetic machinery and transcriptional programs is warranted to develop effective mechanism-based therapeutic strategies. The clinical application of epigenetic drugs-also known as "epi-drugs"-is currently exploding in the field of cardiovascular disease. The present review describes the main epigenetic networks underlying cardiometabolic alterations and sheds light on specific points of intervention for pharmacological reprogramming in this setting.


Assuntos
Doenças Cardiovasculares/genética , Endotélio Vascular/metabolismo , Epigênese Genética , Síndrome Metabólica/genética , Animais , Fármacos Cardiovasculares/uso terapêutico , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/metabolismo , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiopatologia , Epigênese Genética/efeitos dos fármacos , Interação Gene-Ambiente , Humanos , Síndrome Metabólica/tratamento farmacológico , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/metabolismo , Fatores de Risco , Transdução de Sinais
5.
Ecotoxicol Environ Saf ; 205: 111165, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32836160

RESUMO

BACKGROUND: Bisphenol A (BPA) is a well-known xenobiotic endocrine disrupting chemical, with estrogenic activity and many other potential biological effects. Although multiple toxicities have been reported for BPA, molecular mechanisms underlying the transgenerational toxic effects of BPA are still underestimated. METHODS: Parental F0 fish were exposed to 1.0 µM BPA or control (0.1% DMSO, v/v) for 7 days. Eggs (F1) were collected and kept in control medium until 4.5 or 120 h post fertilization (hpf). RNA sequencing (RNA-seq) was conducted on embryos and larvae, to discover differentially expressed genes (DEGs), and then KEGG pathway, GO enrichment and GSEA were performed to interpret functional ontology. Histopathology was performed to explore the morphological and structural alterations in liver tissues of zebrafish larvae (120 hpf) after parental BPA exposure. RESULTS: Parental BPA exposure induced global transcriptomic changes in zebrafish embryos and larvae. For embryos, epigenetic regulation genes were decidedly affected, highlighted epigenotoxicity might involve in the transgenerational effects during embryogenesis and early development. By further investigation on its delayed effects, our RNA-Seq data of larvae suggested ROS metabolic process, apoptosis, p53 and MAPK signaling pathway were concentrated, indicating defensive cellular processes still involved in protecting against BPA toxicity. Furthermore, parental BPA-treated larvae manifested hepatic injury by histopathological analysis. CONCLUSIONS: Parental BPA exposure led to global transcriptomic changes involved in epigenetic regulation, oxidative stress, apoptosis and DNA damage of offspring. These findings advanced the field of the parental-mediated subsequent generational toxic effects of BPA.


Assuntos
Compostos Benzidrílicos/toxicidade , Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Larva/efeitos dos fármacos , Fenóis/toxicidade , Transcriptoma/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/genética , Animais , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário/genética , Epigênese Genética/efeitos dos fármacos , Perfilação da Expressão Gênica , Larva/genética , Análise de Sequência de RNA , Peixe-Zebra/metabolismo
6.
Cancer Sci ; 111(9): 3111-3121, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32639661

RESUMO

Cancer cells are often characterized by abnormalities in DNA damage response including defects in cell cycle checkpoints and/or DNA repair. Synthetic lethality between DNA damage repair (DDR) pathways has provided a paradigm for cancer therapy by targeting DDR. The successful example is that cancer cells with BRCA1/2 mutations are sensitized to poly(adenosine diphosphate [ADP]-ribose)polymerase (PARP) inhibitors. Beyond the narrow scope of defects in the BRCA pathway, "BRCAness" provides more opportunities for synthetic lethality strategy. In human pancreatic cancer, frequent mutations were found in cell cycle and DDR genes, including P16, P73, APC, MLH1, ATM, PALB2, and MGMT. Combined DDR inhibitors and chemotherapeutic agents are under preclinical or clinical trials. Promoter region methylation was found frequently in cell cycle and DDR genes. Epigenetics joins the Knudson's "hit" theory and "BRCAness." Aberrant epigenetic changes in cell cycle or DDR regulators may serve as a new avenue for synthetic lethality strategy in pancreatic cancer.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias Pancreáticas/etiologia , Mutações Sintéticas Letais , Animais , Ciclo Celular/genética , Quimiorradioterapia , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Suscetibilidade a Doenças , Epigênese Genética/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/terapia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Poli(ADP-Ribose) Polimerases/metabolismo , Transdução de Sinais
7.
Bratisl Lek Listy ; 121(8): 558-564, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32726118

RESUMO

BACKGROUND: Goeckerman therapy (GT) of psoriasis involves dermal application of crude coal tar containing polycyclic aromatic hydrocarbons (PAHs) and exposure to ultraviolet radiation (UVR). Little is known about GT influence on DNA epigenetics. OBJECTIVE: The study aim was to discover epigenetic mechanisms altered by the exposure related to the GT of psoriasis. METHODS: Observed group of patients with plaque psoriasis (n = 23) was treated by GT with 3 % CCT. Before and after GT, we analyzed the levels of benzo[a]pyrene-7,8-diol-9,10-epoxide-DNA adducts (BPDE-DNA), p53 protein in serum, 5-methylcytosine (5-mC, global DNA methylation), and methylation in selected CpG sites of p53 gene. RESULTS: We found a significant increase in the levels of BPDE-DNA (p < 0.01) and serum levels of p53 protein (p < 0.01) after GT, and an insignificant decrease in the percentage of 5-mC in peripheral blood DNA. Methylation of p53 CpG sites was affected neither by psoriasis nor by GT. The study confirmed good effectiveness of GT (significantly reduced psoriasis area and severity index; p < 0.001). CONCLUSION: Our findings indicate that there is a significantly increased genotoxic hazard related to the exposure of PAHs and UV radiation after GT of psoriasis. However, global DNA methylation and p53 gene methylation evade the effect of GT, as they remained unchanged (Tab. 4, Fig. 3, Ref. 50).


Assuntos
Epigênese Genética , Hidrocarbonetos Policíclicos Aromáticos , Psoríase , Terapia Ultravioleta , Dano ao DNA , Epigênese Genética/efeitos dos fármacos , Humanos , Hidrocarbonetos Policíclicos Aromáticos/efeitos adversos , Hidrocarbonetos Policíclicos Aromáticos/uso terapêutico , Psoríase/terapia , Raios Ultravioleta , Terapia Ultravioleta/efeitos adversos
8.
Nat Commun ; 11(1): 3326, 2020 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-32620791

RESUMO

Tumour cells adapt to nutrient deprivation in vivo, yet strategies targeting the nutrient poor microenvironment remain unexplored. In melanoma, tumour cells often experience low glutamine levels, which promote cell dedifferentiation. Here, we show that dietary glutamine supplementation significantly inhibits melanoma tumour growth, prolongs survival in a transgenic melanoma mouse model, and increases sensitivity to a BRAF inhibitor. Metabolomic analysis reveals that dietary uptake of glutamine effectively increases the concentration of glutamine in tumours and its downstream metabolite, αKG, without increasing biosynthetic intermediates necessary for cell proliferation. Mechanistically, we find that glutamine supplementation uniformly alters the transcriptome in tumours. Our data further demonstrate that increase in intra-tumoural αKG concentration drives hypomethylation of H3K4me3, thereby suppressing epigenetically-activated oncogenic pathways in melanoma. Therefore, our findings provide evidence that glutamine supplementation can serve as a potential dietary intervention to block melanoma tumour growth and sensitize tumours to targeted therapy via epigenetic reprogramming.


Assuntos
Proliferação de Células/efeitos dos fármacos , Suplementos Nutricionais , Epigênese Genética/efeitos dos fármacos , Glutamina/farmacologia , Melanoma/prevenção & controle , Transdução de Sinais/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Proliferação de Células/genética , Epigênese Genética/genética , Glutamina/administração & dosagem , Histonas/metabolismo , Humanos , Lisina/metabolismo , Masculino , Melanoma/genética , Melanoma/patologia , Metilação/efeitos dos fármacos , Camundongos Nus , Transdução de Sinais/genética , Transcriptoma/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
9.
PLoS One ; 15(7): e0236403, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32716961

RESUMO

Autophagy, a self-degradative physiological process, is critical for homeostasis maintenance and energy source balancing in response to various stresses, including nutrient deprivation. It is a highly conserved catabolic process in eukaryotes and is indispensable for cell survival as it involves degradation of unessential or excessive components and their subsequent recycling as building blocks for the synthesis of necessary molecules. Although the dysregulation of autophagy has been reported to broadly contribute to various diseases, including cancers and neurodegenerative diseases, the molecular mechanisms underlying the epigenetic regulation of autophagy are poorly elucidated. Here, we report that the level of lysine demethylase 3B (KDM3B) increases in nutrient-deprived HCT116 cells, a colorectal carcinoma cell line, resulting in transcriptional activation of the autophagy-inducing genes. KDM3B was found to enhance the transcription by demethylating H3K9me2 on the promoter of these genes. Furthermore, we observed that the depletion of KDM3B inhibited the autophagic flux in HCT116 cells. Collectively, these data suggested the critical role of KDM3B in the regulation of autophagy-related genes via H3K9me2 demethylation and induction of autophagy in nutrient-starved HCT116 cells.


Assuntos
Autofagia/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo , Ativação Transcricional/genética , Aminoácidos/deficiência , Autofagia/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Células HCT116 , Células HEK293 , Histonas/metabolismo , Humanos , Regiões Promotoras Genéticas , Complexo de Endopeptidases do Proteassoma/metabolismo , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Sirolimo/farmacologia , Ativação Transcricional/efeitos dos fármacos , Proteína com Valosina/metabolismo
10.
Adv Pharmacol ; 89: 195-235, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32616207

RESUMO

As a field, psychiatry is undergoing an exciting paradigm shift toward early identification and intervention that will likely minimize both the burden associated with severe mental illnesses as well as their duration. In this context, the rapid-acting antidepressant ketamine has revolutionized our understanding of antidepressant response and greatly expanded the pharmacologic armamentarium for treatment-resistant depression. Efforts to characterize biomarkers of ketamine response support a growing emphasis on early identification, which would allow clinicians to identify biologically enriched subgroups with treatment-resistant depression who are more likely to benefit from ketamine therapy. This chapter presents a broad overview of a range of translational biomarkers, including those drawn from imaging and electrophysiological studies, sleep and circadian rhythms, and HPA axis/endocrine function as well as metabolic, immune, (epi)genetic, and neurotrophic biomarkers related to ketamine response. Ketamine's unique, rapid-acting properties may serve as a model to explore a whole new class of novel rapid-acting treatments with the potential to revolutionize drug development and discovery. However, it should be noted that although several of the biomarkers reviewed here provide promising insights into ketamine's mechanism of action, most studies have focused on acute rather than longer-term antidepressant effects and, at present, none of the biomarkers are ready for clinical use.


Assuntos
Biomarcadores/metabolismo , Encéfalo/metabolismo , Ketamina/uso terapêutico , Encéfalo/efeitos dos fármacos , Encéfalo/imunologia , Ritmo Circadiano/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Humanos , Ketamina/farmacologia
11.
PLoS One ; 15(7): e0235556, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32614916

RESUMO

To gain a better insight into the selenium nanoparticle (nSe) benefits/toxicity, this experiment was carried out to address the behavior of bitter melon seedlings to nSe (0, 1, 4, 10, 30, and 50 mgL-1) or bulk form (selenate). Low doses of nSe increased biomass accumulation, while concentrations of 10 mgL-1 and above were associated with stem bending, impaired root meristem, and severe toxicity. Responses to nSe were distinct from that of bulk in that the nano-type exhibited a higher efficiency to stimulate growth and organogenesis than the bulk. The bulk form displayed higher phytotoxicity than the nano-type counterpart. According to the MSAP-based analysis, nSe mediated substantial variation in DNA cytosine methylation, reflecting the epigenetic modification. By increasing the concentration of nSe, the expression of the WRKY1 transcription factor linearly up-regulated (mean = 7.9-fold). Transcriptions of phenylalanine ammonia-lyase (PAL) and 4-Coumarate: CoA-ligase (4CL) genes were also induced. The nSe treatments at low concentrations enhanced the activity of leaf nitrate reductase (mean = 52%) in contrast with the treatment at toxic concentrations. The toxic concentration of nSe increased leaf proline concentration by 80%. The nSe supplement also stimulated the activities of peroxidase (mean = 35%) and catalase (mean = 10%) enzymes. The nSe-treated seedlings exhibited higher PAL activity (mean = 39%) and soluble phenols (mean = 50%). The nSe toxicity was associated with a disrupted differentiation of xylem conducting tissue. The callus formation and performance of the explants originated from the nSe-treated seedlings had a different trend than that of the control. This experiment provides new insights into the nSe-associated advantage/ cytotoxicity and further highlights the necessity of designing convincing studies to introduce novel methods for plant cell/tissue cultures and agriculture.


Assuntos
Metilação de DNA/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Momordica charantia/metabolismo , Nanopartículas/toxicidade , Selênio/química , Citosina/metabolismo , Momordica charantia/efeitos dos fármacos , Momordica charantia/crescimento & desenvolvimento , Nanopartículas/química , Nitrato Redutase/genética , Nitrato Redutase/metabolismo , Fenóis/metabolismo , Fenilalanina Amônia-Liase/genética , Fenilalanina Amônia-Liase/metabolismo , Folhas de Planta/enzimologia , Folhas de Planta/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Prolina/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação para Cima/efeitos dos fármacos
12.
Cancer Immunol Immunother ; 69(11): 2169-2178, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32648166

RESUMO

T-cell receptor (TCR)- and chimeric antigen receptor (CAR)-based adoptive cell transfer (ACT) has shown promising results in hematological malignancies, but remains immature in solid cancers. The challenges associated with identification of tumor-specific targets, the heterogenic antigen expression, limited T-cell trafficking to tumor sites and the hostile tumor microenvironment (TME), are all factors contributing to the limited efficacy of ACT therapies against solid tumors. Epigenetic priming of tumor cells and the microenvironment may be a way of overcoming these obstacles and improving the clinical efficacy of adoptive T-cell therapies in the future. Here, we review the current literature and suggest combining epigenetic modulators and ACT strategies as a way of augmenting the efficacy of TCR- and CAR-engineered T cells against solid tumors.


Assuntos
Terapia Combinada/métodos , Epigênese Genética , Imunoterapia Adotiva/métodos , Neoplasias , Linfócitos T/transplante , Animais , Antígenos de Neoplasias/imunologia , Metilases de Modificação do DNA/antagonistas & inibidores , Epigênese Genética/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Humanos , Neoplasias/imunologia , Neoplasias/terapia , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/imunologia , Evasão Tumoral/imunologia , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia
13.
Cancer Sci ; 111(9): 3142-3154, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32536012

RESUMO

Colorectal cancer (CRC) is a public health problem. It is the third most common cancer in the world, with nearly 1.8 million new cases diagnosed in 2018. The only curative treatment is surgery, especially for early tumor stages. When there is locoregional or distant invasion, chemotherapy can be introduced, in particular 5-fluorouracil (5-FU). However, the disease can become tolerant to these pharmaceutical treatments: resistance emerges, leading to early tumor recurrence. Different mechanisms can explain this 5-FU resistance. Some are disease-specific, whereas others, such as drug efflux, are evolutionarily conserved. These mechanisms are numerous and complex and can occur simultaneously in cells exposed to 5-FU. In this review, we construct a global outline of different mechanisms from disruption of 5-FU-metabolic enzymes and classic cellular processes (apoptosis, autophagy, glucose metabolism, oxidative stress, respiration, and cell cycle perturbation) to drug transporters and epithelial-mesenchymal transition induction. Particular interest is directed to tumor microenvironment function as well as epigenetic alterations and miRNA dysregulation, which are the more promising processes that will be the subject of much research in the future.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Neoplasias Colorretais/metabolismo , Resistencia a Medicamentos Antineoplásicos , Fluoruracila/farmacologia , Transdução de Sinais/efeitos dos fármacos , Antimetabólitos Antineoplásicos/metabolismo , Biomarcadores , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Metabolismo Energético/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Fluoruracila/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Redes e Vias Metabólicas , Estresse Oxidativo/efeitos dos fármacos , Timidilato Sintase/metabolismo , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/genética
14.
Life Sci ; 256: 117974, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32553924

RESUMO

The brain tumor is the abnormal growth of heterogeneous cells around the central nervous system and spinal cord. Most clinically prominent brain tumors affecting both adult and pediatric are glioblastoma, medulloblastoma, and ependymoma and they are classified according to their origin of tissue. Chemotherapy, radiotherapy, and surgery are important treatments available to date. However, these treatments fail due to multiple reasons, including chemoresistance and radiation resistance of cancer cells. Thus, there is a need of new therapeutic designs to target cell signaling and molecular events which are responsible for this resistance. Recently epigenetic changes received increased attention because it helps in understanding chromatin-mediated disease mechanism. The epigenetic modification alters chromatin structure that affects the docking site of many drugs which cause chemo-resistance of cancer therapy. This review centers the mechanism of how epigenetic changes affect the transcription repression and activation of various genes including Polycomb gene, V-Myc avian myelocytomatosis viral oncogene (MYCN). This review also put forth the pathway of radiation-induced reactive oxygen species generation and its role in epigenetic changes in the cellular level and its impact on tissue physiology. Additionally, there is a strong relationship between the behavior of an individual and environment-induced epigenetic regulation of gene expression. The review also discusses Transcriptome heterogeneity and role of tumor microenvironment in glioblastoma. Overall, this review emphasis important and novel epigenetic targets that could be of therapeutic benefit, which helps in overcoming the unsolved chromatin alteration in brain cancer.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/radioterapia , Epigênese Genética/genética , Animais , Neoplasias Encefálicas/metabolismo , Epigênese Genética/efeitos dos fármacos , Epigênese Genética/efeitos da radiação , Humanos , Radiossensibilizantes/farmacologia , Radiossensibilizantes/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Transcriptoma/efeitos dos fármacos , Transcriptoma/genética , Transcriptoma/efeitos da radiação , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/genética , Microambiente Tumoral/efeitos da radiação
15.
Ecotoxicol Environ Saf ; 201: 110802, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32531573

RESUMO

Extended exposure to inorganic arsenic through contaminated drinking water has been linked with increased incidence of diabetes mellitus. The most common exposure occurs through the consumption of contaminated drinking water mainly through geogenic sources of inorganic arsenic. Epigenetic modifications are important mechanisms through which environmental pollutants could exert their toxic effects. Bisulfite sequencing polymerase chain reaction method followed by Sanger sequencing was performed for DNA methylation analysis. Our results showed that sodium arsenite treatment significantly reduced insulin secretion in pancreatic islets. It was revealed that the methylation of glucose transporter 2 (Glut2) gene was changed at two cytosine-phosphate-guanine (CpG) sites (-1743, -1734) in the promoter region of the sodium arsenite-treated group comparing to the control. No changes were observed in the methylation status of peroxisome proliferator-activated receptor-gamma (PPARγ), pancreatic and duodenal homeobox 1 (Pdx1) and insulin 2 (Ins2) CpG sites in the targeted regions. Measuring the gene expression level showed increase in Glut2 expression, while the expression of insulin (INS) and Pdx1 were significantly affected by sodium arsenite treatment. This study revealed that exposure to sodium arsenite changed the DNA methylation pattern of Glut2, a key transporter of glucose entry into the pancreatic beta cells (ß-cells). Our data suggested possible epigenetic-mediated toxicity mechanism for arsenite-induced ß-cells dysfunction. Further studies are needed to dissect the precise epigenetic modulatory activity of sodium arsenite that affect the biogenesis of insulin.


Assuntos
Arsenitos/toxicidade , Metilação de DNA/efeitos dos fármacos , Transportador de Glucose Tipo 2/genética , Insulina/metabolismo , Ilhotas Pancreáticas/efeitos dos fármacos , Compostos de Sódio/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Epigênese Genética/efeitos dos fármacos , Proteínas de Homeodomínio/genética , Técnicas In Vitro , Insulina/genética , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Masculino , Regiões Promotoras Genéticas , Ratos , Ratos Wistar , Transativadores/genética
16.
Chemosphere ; 258: 127360, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32554016

RESUMO

Environmental pollutants are thought to be a risk factor for the prevalence of hepatic steatosis. Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous, and human exposure is inevitable. In the present study, phenanthrene (Phe) was used as a representative PAH to investigate the effects of in utero exposure to PAH on hepatic lipid metabolism and the toxicological mechanism involved. Pregnant mice (C57BL/6J) were orally administered Phe (0, 60, 600 and 6000 µg kg-1 body weight) once every 3 days with 6 doses in total. F1 female mice aged 125 days showed significantly elevated hepatic lipid levels in the liver. The protein expression of hepatic peroxisome proliferator-activated receptors (PPARß and PPARγ) and retinoid X receptors (RXRs) was upregulated; the transcription of genes related to lipogenesis, such as srebp1 (encoding sterol regulatory element binding proteins), acca (acetyl-CoA carboxylase), fasn (fatty acid synthase) and pcsk9 (proprotein convertase subtilisin/kexin type 9), showed an upregulation, while the mRNA levels of the lipolysis gene lcat (encoding lecithin cholesterol acyl transferase) were downregulated. These results could be responsible for lipid accumulation. The promoter methylation levels of pparγ were reduced and were the lowest in the 600 µg kg-1 group, and the promoter methylation levels of lcat were significantly increased in all the Phe treatments. These changes were matched with the alterations in their mRNA levels, suggesting that prenatal Phe exposure could induce abnormal lipid metabolism in later life via epigenetic modification.


Assuntos
Poluentes Ambientais/toxicidade , Epigênese Genética/efeitos dos fármacos , Fígado Gorduroso/virologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Fenantrenos/toxicidade , Efeitos Tardios da Exposição Pré-Natal/virologia , Idoso de 80 Anos ou mais , Animais , Fígado Gorduroso/embriologia , Fígado Gorduroso/metabolismo , Feminino , Humanos , Metabolismo dos Lipídeos/genética , Lipogênese/efeitos dos fármacos , Lipogênese/genética , Lipólise/efeitos dos fármacos , Lipólise/genética , Fígado/efeitos dos fármacos , Fígado/crescimento & desenvolvimento , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Transcrição Genética/genética
17.
Anticancer Res ; 40(5): 2559-2565, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32366400

RESUMO

BACKGROUND/AIM: Androgens are essential for the growth of most prostate cancers (PCa). As a result, androgen ablation is the mainstay of the treatment of PCa. Proteins of the polycomb and trithorax family are master epigenetic regulators of cell type specific gene expression including androgen receptor. MATERIALS AND METHODS: We interrogated epigenetic changes of a 24-gene panel corresponding to polycomb and trithorax genes by PCR array and differential gene expression by quantitative real time-PCR on prostate cancer cell line (LNCaP) treated with the synthetic ligand R1881. RESULTS: We observed the highest methylation for CBX2, PCGF6, PHC2, EZH2 and TRIM27 genes and the lowest methylation for CBX8 and PCGF2 (p<0.05), and a modest decrease in the expression of EZH2. CONCLUSION: Differential methylation profiles of polycomb and trithorax genes may contribute to the dynamics of prostate carcinogenesis.


Assuntos
Androgênios/farmacologia , Epigênese Genética/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Histona-Lisina N-Metiltransferase/genética , Proteína de Leucina Linfoide-Mieloide/genética , Proteínas do Grupo Polycomb/genética , Neoplasias da Próstata/genética , Androgênios/metabolismo , Linhagem Celular Tumoral , Metilação de DNA , Humanos , Masculino , Receptores Androgênicos/metabolismo
18.
Nat Commun ; 11(1): 2316, 2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32385268

RESUMO

Our early-life environment has a profound influence on developing organs that impacts metabolic function and determines disease susceptibility across the life-course. Using a rat model for exposure to an endocrine disrupting chemical (EDC), we show that early-life chemical exposure causes metabolic dysfunction in adulthood and reprograms histone marks in the developing liver to accelerate acquisition of an adult epigenomic signature. This epigenomic reprogramming persists long after the initial exposure, but many reprogrammed genes remain transcriptionally silent with their impact on metabolism not revealed until a later life exposure to a Western-style diet. Diet-dependent metabolic disruption was largely driven by reprogramming of the Early Growth Response 1 (EGR1) transcriptome and production of metabolites in pathways linked to cholesterol, lipid and one-carbon metabolism. These findings demonstrate the importance of epigenome:environment interactions, which early in life accelerate epigenomic aging, and later in adulthood unlock metabolically restricted epigenetic reprogramming to drive metabolic dysfunction.


Assuntos
Epigenoma/genética , Animais , Metilação de DNA/efeitos dos fármacos , Metilação de DNA/genética , Proteína 1 de Resposta de Crescimento Precoce/genética , Disruptores Endócrinos/toxicidade , Epigênese Genética/efeitos dos fármacos , Epigênese Genética/genética , Epigenômica/métodos , Feminino , Interação Gene-Ambiente , Estudo de Associação Genômica Ampla , Masculino , Ratos
19.
Nat Commun ; 11(1): 2086, 2020 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-32350249

RESUMO

Gain of function (GOF) DNA binding domain (DBD) mutations of TP53 upregulate chromatin regulatory genes that promote genome-wide histone methylation and acetylation. Here, we therapeutically exploit the oncogenic GOF mechanisms of p53 codon 158 (Arg158) mutation, a DBD mutant found to be prevalent in lung carcinomas. Using high throughput compound screening and combination analyses, we uncover that acetylating mutp53R158G could render cancers susceptible to cisplatin-induced DNA stress. Acetylation of mutp53R158G alters DNA binding motifs and upregulates TRAIP, a RING domain-containing E3 ubiquitin ligase which dephosphorylates IĸB and impedes nuclear translocation of RelA (p65), thus repressing oncogenic nuclear factor kappa-B (NF-ĸB) signaling and inducing apoptosis. Given that this mechanism of cytotoxic vulnerability appears inapt in p53 wild-type (WT) or other hotspot GOF mutp53 cells, our work provides a therapeutic opportunity specific to Arg158-mutp53 tumors utilizing a regimen consisting of DNA-damaging agents and mutp53 acetylators, which is currently being pursued clinically.


Assuntos
Códon/genética , Mutação/genética , Neoplasias/genética , Proteína Supressora de Tumor p53/genética , Acetilação/efeitos dos fármacos , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Apoptose/genética , Caspase 3/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cisplatino/farmacologia , Epigênese Genética/efeitos dos fármacos , Mutação com Ganho de Função/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Ácidos Hidroxâmicos/farmacologia , Camundongos SCID , Modelos Biológicos , Proteínas Mutantes/metabolismo , NF-kappa B/metabolismo , Neoplasias/tratamento farmacológico , Motivos de Nucleotídeos/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Ligação Proteica/efeitos dos fármacos , Isoformas de Proteínas/genética , Sulfonamidas/farmacologia , Topotecan/farmacologia , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
20.
PLoS One ; 15(5): e0233468, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32469975

RESUMO

Transcription disequilibria are characteristic of many neurodegenerative diseases. The activity-evoked transcription of immediate early genes (IEGs), important for neuronal plasticity, memory and behavior, is altered in CNS diseases and governed by epigenetic modulation. KDM1A, a histone 3 lysine 4 demethylase that forms part of transcription regulation complexes, has been implicated in the control of IEG transcription. Here we report the development of vafidemstat (ORY-2001), a brain penetrant inhibitor of KDM1A and MAOB. ORY-2001 efficiently inhibits brain KDM1A at doses suitable for long term treatment, and corrects memory deficit as assessed in the novel object recognition testing in the Senescence Accelerated Mouse Prone 8 (SAMP8) model for accelerated aging and Alzheimer's disease. Comparison with a selective KDM1A or MAOB inhibitor reveals that KDM1A inhibition is key for efficacy. ORY-2001 further corrects behavior alterations including aggression and social interaction deficits in SAMP8 mice and social avoidance in the rat rearing isolation model. ORY-2001 increases the responsiveness of IEGs, induces genes required for cognitive function and reduces a neuroinflammatory signature in SAMP8 mice. Multiple genes modulated by ORY-2001 are differentially expressed in Late Onset Alzheimer's Disease. Most strikingly, the amplifier of inflammation S100A9 is highly expressed in LOAD and in the hippocampus of SAMP8 mice, and down-regulated by ORY-2001. ORY-2001 is currently in multiple Phase IIa studies.


Assuntos
Inibidores Enzimáticos/farmacologia , Histona Desmetilases/antagonistas & inibidores , Transtornos da Memória/tratamento farmacológico , Inibidores da Monoaminoxidase/farmacologia , Envelhecimento/efeitos dos fármacos , Envelhecimento/psicologia , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/psicologia , Animais , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/fisiopatologia , Modelos Animais de Doenças , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacocinética , Epigênese Genética/efeitos dos fármacos , Feminino , Expressão Gênica/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Inibidores da Monoaminoxidase/química , Inibidores da Monoaminoxidase/farmacocinética , Ratos , Ratos Sprague-Dawley
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