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1.
Nat Commun ; 12(1): 1536, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33750776

RESUMO

Hyperactivation of the MAPK signaling pathway motivates the clinical use of MAPK inhibitors for BRAF-mutant melanomas. Heterogeneity in differentiation state due to epigenetic plasticity, however, results in cell-to-cell variability in the state of MAPK dependency, diminishing the efficacy of MAPK inhibitors. To identify key regulators of such variability, we screen 276 epigenetic-modifying compounds, individually or combined with MAPK inhibitors, across genetically diverse and isogenic populations of melanoma cells. Following single-cell analysis and multivariate modeling, we identify three classes of epigenetic inhibitors that target distinct epigenetic states associated with either one of the lysine-specific histone demethylases Kdm1a or Kdm4b, or BET bromodomain proteins. While melanocytes remain insensitive, the anti-tumor efficacy of each inhibitor is predicted based on melanoma cells' differentiation state and MAPK activity. Our systems pharmacology approach highlights a path toward identifying actionable epigenetic factors that extend the BRAF oncogene addiction paradigm on the basis of tumor cell differentiation state.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Epigenômica/métodos , Melanoma/metabolismo , Vício Oncogênico , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Feminino , Histona Desmetilases/metabolismo , Humanos , Histona Desmetilases com o Domínio Jumonji/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Melanócitos/metabolismo , Melanoma/genética , Camundongos , Camundongos Nus , Mutação , Vício Oncogênico/genética , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/genética , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Anticancer Res ; 41(1): 113-122, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33419804

RESUMO

BACKGROUND/AIM: The aim of the study was to investigate the effects of hypoxia on proliferation and the expression of HIF-1α (hypoxia-inducible factor 1 alpha) and JMJD1A (jumonji domain 1A) in head and neck squamous cell carcinoma (HNSCC). MATERIALS AND METHODS: FaDu and HLaC78 cells were incubated for 1-24 h in hypoxia and normoxia. Cell proliferation, mRNA and protein levels of HIF-1α and JMJD1A were quantified by counting, PCR and western blot. RESULTS: Hypoxia led to a constant decrease in cell proliferation. Short hypoxia resulted in an increase in HIF-1α mRNA levels. This effect was reversed after longer incubation. The western blot for HIF-1α showed a maximum accumulation after 3-6 h of hypoxia. In FaDu cells, the concentration of JMJD1A reached a peak after 6 h and decreased thereafter, whereas in HLaC78 cells, it presented a second peak after 48 h. CONCLUSION: The transcription factors HIF-1α and JMJDA1 were confirmed as relevant hypoxia-dependent regulators of carcinogenesis in HNSCC.


Assuntos
Regulação Neoplásica da Expressão Gênica , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Hipóxia/genética , Hipóxia/metabolismo , Histona Desmetilases com o Domínio Jumonji/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Hipóxia Celular/genética , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular/genética , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Histona Desmetilases com o Domínio Jumonji/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia
3.
Cell Death Dis ; 11(12): 1068, 2020 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-33318475

RESUMO

Esophageal squamous cell carcinoma (ESCC), the most frequent esophageal cancer (EC) subtype, entails dismal prognosis. Hypoxia, a common feature of advanced ESCC, is involved in resistance to radiotherapy (RT). RT response in hypoxia might be modulated through epigenetic mechanisms, constituting novel targets to improve patient outcome. Post-translational methylation in histone can be partially modulated by histone lysine demethylases (KDMs), which specifically removes methyl groups in certain lysine residues. KDMs deregulation was associated with tumor aggressiveness and therapy failure. Thus, we sought to unveil the role of Jumonji C domain histone lysine demethylases (JmjC-KDMs) in ESCC radioresistance acquisition. The effectiveness of RT upon ESCC cells under hypoxic conditions was assessed by colony formation assay. KDM3A/KDM6B expression, and respective H3K9me2 and H3K27me3 target marks, were evaluated by RT-qPCR, Western blot, and immunofluorescence. Effect of JmjC-KDM inhibitor IOX1, as well as KDM3A knockdown, in in vitro functional cell behavior and RT response was assessed in ESCC under hypoxic conditions. In vivo effect of combined IOX1 and ionizing radiation treatment was evaluated in ESCC cells using CAM assay. KDM3A, KDM6B, HIF-1α, and CAIX immunoexpression was assessed in primary ESCC and normal esophagus. Herein, we found that hypoxia promoted ESCC radioresistance through increased KDM3A/KDM6B expression, enhancing cell survival and migration and decreasing DNA damage and apoptosis, in vitro. Exposure to IOX1 reverted these features, increasing ESCC radiosensitivity and decreasing ESCC microtumors size, in vivo. KDM3A was upregulated in ESCC tissues compared to the normal esophagus, associating and colocalizing with hypoxic markers (HIF-1α and CAIX). Therefore, KDM3A upregulation in ESCC cell lines and primary tumors associated with hypoxia, playing a critical role in EC aggressiveness and radioresistance. KDM3A targeting, concomitant with conventional RT, constitutes a promising strategy to improve ESCC patients' survival.


Assuntos
Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/metabolismo , Carcinoma de Células Escamosas do Esôfago/patologia , Histona Desmetilases com o Domínio Jumonji/metabolismo , Tolerância a Radiação , Hipóxia Tumoral , Apoptose/efeitos dos fármacos , Apoptose/genética , Apoptose/efeitos da radiação , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Movimento Celular/efeitos da radiação , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Dano ao DNA , Reparo do DNA/efeitos dos fármacos , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Humanos , Hidroxiquinolinas/farmacologia , Histona Desmetilases com o Domínio Jumonji/genética , Tolerância a Radiação/efeitos dos fármacos , Radiação Ionizante , Hipóxia Tumoral/efeitos dos fármacos , Hipóxia Tumoral/genética , Hipóxia Tumoral/efeitos da radiação
4.
Nat Commun ; 11(1): 5061, 2020 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-33033262

RESUMO

The interplay between the Yamanaka factors (OCT4, SOX2, KLF4 and c-MYC) and transcriptional/epigenetic co-regulators in somatic cell reprogramming is incompletely understood. Here, we demonstrate that the histone H3 lysine 27 trimethylation (H3K27me3) demethylase JMJD3 plays conflicting roles in mouse reprogramming. On one side, JMJD3 induces the pro-senescence factor Ink4a and degrades the pluripotency regulator PHF20 in a reprogramming factor-independent manner. On the other side, JMJD3 is specifically recruited by KLF4 to reduce H3K27me3 at both enhancers and promoters of epithelial and pluripotency genes. JMJD3 also promotes enhancer-promoter looping through the cohesin loading factor NIPBL and ultimately transcriptional elongation. This competition of forces can be shifted towards improved reprogramming by using early passage fibroblasts or boosting JMJD3's catalytic activity with vitamin C. Our work, thus, establishes a multifaceted role for JMJD3, placing it as a key partner of KLF4 and a scaffold that assists chromatin interactions and activates gene transcription.


Assuntos
Reprogramação Celular , Histona Desmetilases com o Domínio Jumonji/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Animais , Catálise , Proliferação de Células , Senescência Celular , Desmetilação , Elementos Facilitadores Genéticos/genética , Células Epiteliais/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Genoma , Histonas/metabolismo , Lisina/metabolismo , Camundongos , Modelos Biológicos , Regiões Promotoras Genéticas , Ativação Transcricional/genética
5.
Cell Prolif ; 53(11): e12920, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33029857

RESUMO

OBJECTIVES: The level of histone H3 lysine 79 methylation is regulated by the cell cycle and involved in cell proliferation. KDM2B is an H3K79 demethylase. Proliferating cell nuclear antigen (PCNA) is a component of the DNA replication machinery. This study aimed at elucidating a molecular link between H3K79me recognition of PCNA and cell cycle control. MATERIALS AND METHODS: We generated KDM2B-depleted 293T cells and histone H3-K79R mutant-expressing 293T cells. Western blots were primarily utilized to examine the H3K79me level and its effect on subsequent PCNA dissociation from chromatin. We applied IP, peptide pull-down, isothermal titration calorimetry (ITC) and ChIP experiments to show the PCNA binding towards methylated H3K79 and DNA replication origins. Flow cytometry, MTT, iPOND and DNA fibre assays were used to assess the necessity of KDM2B for DNA replication and cell proliferation. RESULTS: We revealed that KDM2B-mediated H3K79 demethylation regulated cell cycle progression. We found that PCNA bound chromatin in an H3K79me-dependent manner during S phase. KDM2B was responsible for the timely dissociation of PCNA from chromatin, allowing to efficient DNA replication. Depletion of KDM2B aberrantly enriched chromatin with PCNA and caused slow dissociation of residual PCNA, leading to a negative effect on cell proliferation. CONCLUSIONS: We suggested a novel interaction between PCNA and H3K79me. Thus, our findings provide a new mechanism of KDM2B in regulation of DNA replication and cell proliferation.


Assuntos
Replicação do DNA , Proteínas F-Box/metabolismo , Histonas/metabolismo , Histona Desmetilases com o Domínio Jumonji/metabolismo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ciclo Celular , Proliferação de Células , Cromatina , Desmetilação , Células HEK293 , Humanos , Fase S
6.
PLoS One ; 15(10): e0236612, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33104714

RESUMO

A precisely balanced activity of canonical Wnt signaling is essential for a number of biological processes and its perturbation leads to developmental defects or diseases. Here, we demonstrate that alternative isoforms of the KDM2A and KDM2B lysine demethylases have the ability to negatively regulate canonical Wnt signaling. These KDM2A and KDM2B isoforms (KDM2A-SF and KDM2B-SF) lack the N-terminal demethylase domain, but they still have the ability to bind to CpG islands in promoters and to interact with their protein partners via their other functional domains. We have observed that KDM2A-SF and KDM2B-SF bind to the promoters of axin 2 and cyclin D1, two canonical Wnt signaling target genes, and repress their activity. Moreover, KDM2A-SF and KDM2B-SF are both able to strongly repress a Wnt-responsive luciferase reporter. The transcriptional repression mediated by KDM2A-SF and KDM2B-SF, but also by KDM2A-LF, is dependent on their DNA binding domain, while the N-terminal demethylase domain is dispensable for this process. Surprisingly, KDM2B-LF is unable to repress both the endogenous promoters and the luciferase reporter. Finally, we show that both KDM2A-SF and KDM2B-SF are able to interact with TCF7L1, one of the transcriptional mediators of canonical Wnt signaling. KDM2A-SF and KDM2B-SF are thus likely to negatively affect the transcription of canonical Wnt signaling target genes by binding to their promoters and by interacting with TCF7L1 and other co-repressors.


Assuntos
Ciclina D1/metabolismo , Proteínas F-Box/metabolismo , Regulação da Expressão Gênica , Histona Desmetilases com o Domínio Jumonji/metabolismo , Regiões Promotoras Genéticas , Proteína 1 Semelhante ao Fator 7 de Transcrição/metabolismo , Via de Sinalização Wnt , Ilhas de CpG , Ciclina D1/genética , Proteínas F-Box/genética , Células HEK293 , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Lisina/genética , Lisina/metabolismo , Isoformas de Proteínas , Proteína 1 Semelhante ao Fator 7 de Transcrição/genética
7.
PLoS Genet ; 16(9): e1008993, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32925902

RESUMO

Plant NLR-type receptors serve as sensitive triggers of host immunity. Their expression has to be well-balanced, due to their interference with various cellular processes and dose-dependency of their defense-inducing activity. A genetic "arms race" with fast-evolving pathogenic microbes requires plants to constantly innovate their NLR repertoires. We previously showed that insertion of the COPIA-R7 retrotransposon into RPP7 co-opted the epigenetic transposon silencing signal H3K9me2 to a new function promoting expression of this Arabidopsis thaliana NLR gene. Recruitment of the histone binding protein EDM2 to COPIA-R7-associated H3K9me2 is required for optimal expression of RPP7. By profiling of genome-wide effects of EDM2, we now uncovered additional examples illustrating effects of transposons on NLR gene expression, strongly suggesting that these mobile elements can play critical roles in the rapid evolution of plant NLR genes by providing the "raw material" for gene expression mechanisms. We further found EDM2 to have a global role in NLR expression control. Besides serving as a positive regulator of RPP7 and a small number of other NLR genes, EDM2 acts as a suppressor of a multitude of additional NLR genes. We speculate that the dual functionality of EDM2 in NLR expression control arose from the need to compensate for fitness penalties caused by high expression of some NLR genes by suppression of others. Moreover, we are providing new insights into functional relationships of EDM2 with its interaction partner, the RNA binding protein EDM3/AIPP1, and its target gene IBM1, encoding an H3K9-demethylase.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas NLR/genética , Receptores Imunológicos/genética , Fatores de Transcrição/genética , Arabidopsis , Proteínas de Arabidopsis/metabolismo , Epigênese Genética , Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Histona Desmetilases com o Domínio Jumonji/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo , Proteínas NLR/biossíntese , Proteínas NLR/metabolismo , Dedos de Zinco PHD , Plantas Geneticamente Modificadas , Domínios Proteicos , Proteínas de Ligação a RNA/genética , Fatores de Transcrição/metabolismo
8.
Mol Cell Biol ; 40(20)2020 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-32817139

RESUMO

Lysine demethylase 6A (KDM6A), also known as UTX, belongs to the KDM6 family of histone H3 lysine 27 (H3K27) demethylases, which also includes UTY and KDM6B (JMJD3). The KDM6A protein contains six tetratricopeptide repeat (TPR) domains and an enzymatic Jumonji C (JmjC) domain that catalyzes the removal of di- and trimethylation on H3K27. KDM6A physically associates with histone H3 lysine 4 monomethyltransferases MLL3 (KMT2C) and MLL4 (KMT2D). Since its identification as an H3K27 demethylase in 2007, studies have reported KDM6A's critical roles in cell differentiation, development, and cancer. KDM6A is important for differentiation of embryonic stem cells and development of various tissues. Mutations of KDM6A cause Kabuki syndrome. KDM6A is frequently mutated in cancers and functions as a tumor suppressor. KDM6A is redundant with UTY and functions largely independently of its demethylase activity. It regulates gene expression, likely through the associated transcription factors and MLL3/4 on enhancers. However, KDM6A enzymatic activity is required in certain cellular contexts. Functional redundancy between H3K27 demethylase activities of KDM6A and KDM6B in vivo has yet to be determined. Further understanding of KDM6A functions and working mechanisms will provide more insights into enhancer regulation and may help generate novel therapeutic approaches to treat KDM6A-related diseases.


Assuntos
Diferenciação Celular/genética , Regulação da Expressão Gênica/genética , Histona Desmetilases/genética , Neoplasias/genética , Domínio Catalítico/genética , Montagem e Desmontagem da Cromatina/genética , Células-Tronco Embrionárias/citologia , Genes Supressores de Tumor , Histona Desmetilases/metabolismo , Humanos , Histona Desmetilases com o Domínio Jumonji/metabolismo , Proteínas Nucleares/metabolismo
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.
Int Heart J ; 61(4): 815-821, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32684588

RESUMO

MiR-134-5p was found to have potential diagnostic value for myocardial infarction (MI), but its biological role in MI has not been reported. In this study, MI mouse model was established. Quantitative real-time PCR (qRT-PCR) and western blot were used to measure the expression of miR-134-5p, lysine demethylase 2A (KDM2A), and vascular endothelial growth factor (VEGF). Dual-Luciferase reporter (DLR) assay was used to explore the relationship between miR-134-5p and KDM2A. The influence of miR-134-5p on cardiomyocytes apoptosis was detected using methyl thiazolyl tetrazolium (MTT) assay. The results revealed that miR-134-5p was highly expressed in infarction tissues of MI mice. Knockdown of miR-134-5p inhibited hypoxia/reoxygenation (H/R) -induced cardiomyocyte apoptosis. In addition, KDM2A was the target gene of miR-134-5p and negatively regulated by miR-134-5p. The promotion effect on the protein level of KDM2A and VEGF induced by miR-134-5p inhibitor can be reversed by shKDM2A in cardiomyocytes. Further, silencing of miR-134-5p promoted myocardial angiogenesis and inhibited myocardial apoptosis via upregulating KDM2A in MI mice. Taken together, our research revealed that knockdown of miR-134-5p increased KDM2A expression, thereby suppressing myocardial apoptosis and promoting myocardial angiogenesis.


Assuntos
Histona Desmetilases com o Domínio Jumonji/metabolismo , MicroRNAs/metabolismo , Infarto do Miocárdio/metabolismo , Animais , Apoptose , Histona Desmetilases com o Domínio Jumonji/genética , Masculino , Camundongos Endogâmicos C57BL , Neovascularização Fisiológica
11.
Mol Cell Endocrinol ; 515: 110917, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32593740

RESUMO

Obesity patients are more susceptible to develop COVID-19 severe outcome due to the role of angiotensin-converting enzyme 2 (ACE2) in the viral infection. ACE2 is regulated in the human cells by different genes associated with increased (TLR3, HAT1, HDAC2, KDM5B, SIRT1, RAB1A, FURIN and ADAM10) or decreased (TRIB3) virus replication. RNA-seq data revealed 14857 genes expressed in human subcutaneous adipocytes, including genes mentioned above. Irisin treatment increased by 3-fold the levels of TRIB3 transcript and decreased the levels of other genes. The decrease in FURIN and ADAM10 expression enriched diverse biological processes, including extracellular structure organization. Our results, in human subcutaneous adipocytes cell culture, indicate a positive effect of irisin on the expression of multiple genes related to viral infection by SARS-CoV-2; furthermore, translatable for other tissues and organs targeted by the novel coronavirus and present, thus, promising approaches for the treatment of COVID-19 infection as therapeutic strategy to decrease ACE2 regulatory genes.


Assuntos
Adipócitos/efeitos dos fármacos , Fibronectinas/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Proteína ADAM10/genética , Proteína ADAM10/metabolismo , Adipócitos/citologia , Adipócitos/metabolismo , Secretases da Proteína Precursora do Amiloide/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Betacoronavirus/genética , Betacoronavirus/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Células Cultivadas , Infecções por Coronavirus/virologia , Fibronectinas/genética , Fibronectinas/metabolismo , Furina/genética , Furina/metabolismo , Ontologia Genética , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo , Histona Desacetilase 2/genética , Histona Desacetilase 2/metabolismo , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Modelos Biológicos , Anotação de Sequência Molecular , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Obesidade/virologia , Pandemias , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/virologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Transdução de Sinais , Sirtuína 1/genética , Sirtuína 1/metabolismo , Receptor 3 Toll-Like/genética , Receptor 3 Toll-Like/metabolismo , Proteínas rab1 de Ligação ao GTP/genética , Proteínas rab1 de Ligação ao GTP/metabolismo
12.
PLoS Genet ; 16(6): e1008511, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32598339

RESUMO

Ribosomal DNA (rDNA) is the most transcribed genomic region and contains hundreds of tandem repeats. Maintaining these rDNA repeats as well as the level of rDNA transcription is essential for cellular homeostasis. DNA damages generated in rDNA need to be efficiently and accurately repaired and rDNA repeats instability has been reported in cancer, aging and neurological diseases. Here, we describe that the histone demethylase JMJD6 is rapidly recruited to nucleolar DNA damage and is crucial for the relocalisation of rDNA in nucleolar caps. Yet, JMJD6 is dispensable for rDNA transcription inhibition. Mass spectrometry analysis revealed that JMJD6 interacts with the nucleolar protein Treacle and modulates its interaction with NBS1. Moreover, cells deficient for JMJD6 show increased sensitivity to nucleolar DNA damage as well as loss and rearrangements of rDNA repeats upon irradiation. Altogether our data reveal that rDNA transcription inhibition is uncoupled from rDNA relocalisation into nucleolar caps and that JMJD6 is required for rDNA stability through its role in nucleolar caps formation.


Assuntos
Dano ao DNA , Histona Desmetilases com o Domínio Jumonji/genética , RNA Ribossômico/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Células HEK293 , Humanos , Histona Desmetilases com o Domínio Jumonji/metabolismo , Proteínas Nucleares/metabolismo , Fosfoproteínas/metabolismo , Ligação Proteica , RNA Ribossômico/metabolismo
13.
J Neuropathol Exp Neurol ; 79(7): 754-762, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32447376

RESUMO

The diagnosis of anaplastic meningioma (AM) (WHO grade III) is based on the presence of a high mitotic index (MI) and/or overt anaplasia. Only few data exist about the reproducibility and prognostic value of overt anaplasia. Additionally, the prognostic value of H3K27me3 loss in AM has not yet been demonstrated. Our objectives were to evaluate the reproducibility and prognostic value of WHO criteria and H3K27me3 loss in a multicenter series of 66 AM. Interobserver reproducibility was good for the determination of WHO grade (Kappa = 0.671) and MI (intraclass correlation coefficient [ICC] = 0.649), and fair for assessment of overt anaplasia (Kappa = 0.366). Patients with meningiomas showing high MI had significantly shorter overall survival (OS) than patients with meningiomas showing overt anaplasia without high MI (p = 0.009). OS was significantly lower in case of overt anaplasia with low MI (<20/1.6 mm2) than in atypical meningiomas (p = 0.008). H3K27me3 loss was present in 10/47 (21%) of AM and independently associated with shorter OS (p = 0.036; Cox multivariate analysis), with a good reproducibility (Kappa = 0.643). In conclusion, the presence of overt anaplasia could give additional prognostic information in tumors lacking high MI. Finally, loss of H3K27me3 is an easy-to-use and reproducible marker of poorer prognosis.


Assuntos
Biomarcadores Tumorais/metabolismo , Histona Desmetilases com o Domínio Jumonji/metabolismo , Neoplasias Meníngeas/metabolismo , Neoplasias Meníngeas/patologia , Meningioma/metabolismo , Meningioma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Feminino , Seguimentos , Humanos , Histona Desmetilases com o Domínio Jumonji/análise , Masculino , Neoplasias Meníngeas/diagnóstico , Meningioma/diagnóstico , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Adulto Jovem
14.
Proc Natl Acad Sci U S A ; 117(11): 6056-6066, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32123118

RESUMO

T helper (Th) cells are CD4+ effector T cells that play a critical role in immunity by shaping the inflammatory cytokine environment in a variety of physiological and pathological situations. Using a combined chemico-genetic approach, we identify histone H3K27 demethylases KDM6A and KDM6B as central regulators of human Th subsets. The prototypic KDM6 inhibitor GSK-J4 increases genome-wide levels of the repressive H3K27me3 chromatin mark and leads to suppression of the key transcription factor RORγt during Th17 differentiation. In mature Th17 cells, GSK-J4 induces an altered transcriptional program with a profound metabolic reprogramming and concomitant suppression of IL-17 cytokine levels and reduced proliferation. Single-cell analysis reveals a specific shift from highly inflammatory cell subsets toward a resting state upon demethylase inhibition. The root cause of the observed antiinflammatory phenotype in stimulated Th17 cells is reduced expression of key metabolic transcription factors, such as PPRC1. Overall, this leads to reduced mitochondrial biogenesis, resulting in a metabolic switch with concomitant antiinflammatory effects. These data are consistent with an effect of GSK-J4 on Th17 T cell differentiation pathways directly related to proliferation and include regulation of effector cytokine profiles. This suggests that inhibiting KDM6 demethylases may be an effective, even in the short term, therapeutic target for autoimmune diseases, including ankylosing spondylitis.


Assuntos
Benzazepinas/farmacologia , Histona Desmetilases/metabolismo , Histonas/metabolismo , Histona Desmetilases com o Domínio Jumonji/metabolismo , Pirimidinas/farmacologia , Células Th17/metabolismo , Doenças Autoimunes/tratamento farmacológico , Doenças Autoimunes/imunologia , Benzazepinas/uso terapêutico , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/imunologia , Código das Histonas/efeitos dos fármacos , Histona Desmetilases/antagonistas & inibidores , Humanos , Interleucina-17/metabolismo , Histona Desmetilases com o Domínio Jumonji/antagonistas & inibidores , Cultura Primária de Células , Pirimidinas/uso terapêutico , RNA-Seq , Espondilite Anquilosante/tratamento farmacológico , Espondilite Anquilosante/imunologia , Células Th17/efeitos dos fármacos , Células Th17/imunologia , Fatores de Transcrição/metabolismo
15.
Life Sci ; 250: 117519, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32147429

RESUMO

OBJECTIVE: Papillary thyroid cancer (PTC) is the most ordinary type of thyroid cancer. Studies pivoting on the mechanisms of microRNAs (miRNAs) are adequately explored but not much on miR-448 in PTC. Thus, this study is proposed to bring forward the uncovered mechanisms of miR-448 in PTC. METHODS: Lysine specific demethylase 5B (KDM5B), miR-448 and transforming growth factor ß-induced factor 1 (TGIF1) expression in PTC tissues and cell lines were detected. The connection between miR-448 expression and clinicopathological characteristics of PTC patients was determined. PTC cell lines TPC-1 and K-1 were transfected with sh-KDM5B, si-TGIF1 or miR-448 mimic to explore their roles in PTC cell progression. Tumor xenografts in nude mice was performed to detect tumor volume and weight. RESULTS: KDM5B and TGIF1 were increased and miR-448 was declined in PTC tissues and cell lines. MiR-448 expression was connected with N stage, lymph node metastasis and advanced tumor node metastasis stage of PTC patients. KDM5B knockdown or TGIF1 reduction or miR-448 elevation undermined PTC cell progression and inhibited tumor growth of nude mice. Down-regulation of miR-448 followed by KDM5B knockdown reversed the effect of decreased KDM5B on the proliferation inhibition and apoptosis promotion of PTC cells. CONCLUSION: Our study elaborates that KDM5B-mediated miR-448 up-regulation restrains PTC cell progression and slows down tumor growth via TGIF1 repression, which provides a novel reference for treatment of PTC.


Assuntos
Carcinoma Papilar/metabolismo , Proteínas de Homeodomínio/metabolismo , Histona Desmetilases com o Domínio Jumonji/metabolismo , MicroRNAs/genética , Proteínas Nucleares/metabolismo , Proteínas Repressoras/metabolismo , Câncer Papilífero da Tireoide/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Idoso , Animais , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Metástase Linfática , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Metástase Neoplásica , Transplante de Neoplasias , Proteínas Nucleares/genética , Proteínas Repressoras/genética , Fator de Crescimento Transformador beta1/metabolismo , Regulação para Cima
16.
Cancer Sci ; 111(5): 1567-1581, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32133742

RESUMO

The histone demethylase lysine-specific demethylase 4A (KDM4A) is reported to be overexpressed and plays a vital in multiple cancers through controlling gene expression by epigenetic regulation of H3K9 or H3K36 methylation marks. However, the biological role and mechanism of KDM4A in prostate cancer (PC) remain unclear. Herein, we reported KDM4A expression was upregulation in phosphatase and tensin homolog knockout mouse prostate tissue. Depletion of KDM4A in PC cells inhibited their proliferation and survival in vivo and vitro. Further studies reveal that USP1 is a deubiquitinase that regulates KDM4A K48-linked deubiquitin and stability. Interestingly, we found c-Myc was a key downstream effector of the USP1-KDM4A/androgen receptor axis in driving PC cell proliferation. Notably, upregulation of KDM4A expression with high USP1 expression was observed in most prostate tumors and inhibition of USP1 promotes PC cells response to therapeutic agent enzalutamide. Our studies propose USP1 could be an anticancer therapeutic target in PC.


Assuntos
Antineoplásicos/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Histona Desmetilases com o Domínio Jumonji/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Proteases Específicas de Ubiquitina/antagonistas & inibidores , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Inibidores Enzimáticos/farmacologia , Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Masculino , Camundongos , Camundongos Mutantes , PTEN Fosfo-Hidrolase/deficiência , Feniltioidantoína/análogos & derivados , Feniltioidantoína/farmacologia , Feniltioidantoína/uso terapêutico , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Ligação Proteica/efeitos dos fármacos , Estabilidade Proteica/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-myc/genética , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteases Específicas de Ubiquitina/genética , Proteases Específicas de Ubiquitina/metabolismo , Ubiquitinação/efeitos dos fármacos
17.
Genes Cells ; 25(6): 402-412, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32215989

RESUMO

Di- and trimethylation of lysine 27 on histone 3 (H3K27me2/3) is a critical gene repression mechanism. We previously showed that down-regulation of the H3K27 demethylase, Jumonji domain-containing protein 3 (JMJD3), resulted in a reduced number of protein kinase C (PKC)α-positive rod ON-bipolar cells. In this work, we focused on the role of another H3K27 demethylase, ubiquitously transcribed tetratricopeptide repeat X chromosome (UTX), in retinal development. UTX was expressed in the retinal progenitor cells of the embryonic mouse retina and was observed in the inner nuclear layer during late retinal development and in the mature retina. The short hairpin RNA-mediated knockdown of Utx in a mouse retinal explant led to a reduced number of PKCα-positive rod ON-bipolar cells. However, other retinal subtypes were unaffected by this knockdown. Using a retina-specific knockout of Utx in mice, the in vivo effects of UTX down-regulation were examined. Again, the number of PKCα-positive rod ON-bipolar cells was reduced, and no other apparent phenotypes, including retinal progenitor proliferation, apoptosis or differentiation, were observed. Finally, we examined retina-specific Utx and Jmjd3 double-knockout mice and found that although the number of rod ON-bipolar cells was reduced, no additional effects from the loss of Utx and Jmjd3 were observed. Taken together, our data show that UTX contributes to retinal differentiation in a lineage-specific manner.


Assuntos
Diferenciação Celular/genética , Histona Desmetilases/metabolismo , Retina/metabolismo , Células Bipolares da Retina/metabolismo , Animais , Apoptose/genética , Linhagem da Célula , Proliferação de Células/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Técnicas de Silenciamento de Genes , Histona Desmetilases/genética , Histona Desmetilases com o Domínio Jumonji/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo , Metilação , Camundongos , Camundongos Knockout , Proteína Quinase C-alfa/metabolismo , Interferência de RNA , Retina/embriologia , Retina/enzimologia , Células Bipolares da Retina/citologia , Células Bipolares da Retina/enzimologia , Células Fotorreceptoras Retinianas Bastonetes/citologia , Células Fotorreceptoras Retinianas Bastonetes/metabolismo
18.
Biochem Biophys Res Commun ; 526(1): 176-183, 2020 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-32201075

RESUMO

Autophagy is an essential process to maintain cell survival and homeostasis under various stress conditions. Here, we report that lysine-specific demethylase 3A (KDM3A) plays an important role in starvation-induced autophagy. Using Kdm3a knockout mice, we demonstrate that KDM3A is crucial for proper hepatic autophagy in vivo. Hepatic mRNA expression analysis and ChIP assay in WT and Kdm3a knockout mouse livers reveal that KDM3A activates autophagy genes by reducing histone H3K9me2 levels upon fasting. Together, our finding represents previously unidentified function of KDM3A as a key regulator of autophagy, implicating potential therapeutic approaches for autophagy-related diseases.


Assuntos
Autofagia , Histona Desmetilases com o Domínio Jumonji/metabolismo , Animais , Autofagossomos/metabolismo , Jejum , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Células Hep G2 , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Fígado/citologia , Fígado/metabolismo , Lisossomos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
19.
Arch Biochem Biophys ; 684: 108334, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32173334

RESUMO

Emerging evidence shows that histone modification and its related regulators are involved in the progression and chemoresistance of ovarian cancer (OC) cells. Our present study found that the expression of Jumonji C domain-containing 2A (JMJD2A), while not JMJD2B or JMJD2C, is increased in OC cells and tissues as compared with that in their corresponding controls. Knockdown of JMJD2A can decrease proliferation while increase cisplatin (CDDP) sensitivity of OC cells. By screening the expression of cytokines involved in the progression of ovarian cancer, we found that knockdown of JMJD2A can inhibit the expression of interleukin-6 (IL-6) and IL-8 in ovarian cancer cells. Recombinant IL-6 (rIL-6) and rIL-8 can attenuate si-JMJD2A-suppressed malignancy of OC cells. Mechanistically, JMJD2A can directly bind with the promoter of IL-6 to trigger its transcription. For IL-8, JMJD2A can increase it mRNA stability in OC cells. Collectively, we revealed that JMJD2A can trigger the malignancy of OC cells via upregulation of IL-6 and IL-8. It suggested that JMJD2A might be a potential target for OC treatment and therapy.


Assuntos
Interleucina-6/metabolismo , Interleucina-8/metabolismo , Histona Desmetilases com o Domínio Jumonji/metabolismo , Neoplasias Ovarianas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Feminino , Regulação Neoplásica da Expressão Gênica/fisiologia , Técnicas de Silenciamento de Genes , Humanos , Interleucina-6/genética , Interleucina-8/genética , Histona Desmetilases com o Domínio Jumonji/genética , Estabilidade de RNA/genética , RNA Mensageiro/metabolismo , Transcrição Genética/fisiologia , Regulação para Cima
20.
Blood ; 135(15): 1255-1269, 2020 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-32068780

RESUMO

The promising activity of BET protein inhibitors (BETi's) is compromised by adaptive or innate resistance in acute myeloid leukemia (AML). Here, modeling of BETi-persister/resistance (BETi-P/R) in human postmyeloproliferative neoplasm (post-MPN) secondary AML (sAML) cells demonstrated accessible and active chromatin in specific superenhancers/enhancers, which was associated with increased levels of nuclear ß-catenin, TCF7L2, JMJD6, and c-Myc in BETi-P/R sAML cells. Following BETi treatment, c-Myc levels were rapidly restored in BETi-P/R sAML cells. CRISPR/Cas9-mediated knockout of TCF7L2 or JMJD6 reversed BETi-P/R, whereas ectopic overexpression conferred BETi-P/R in sAML cells, confirming the mechanistic role of the ß-catenin-TCF7L2-JMJD6-c-Myc axis in BETi resistance. Patient-derived, post-MPN, CD34+ sAML blasts exhibiting relative resistance to BETi, as compared with sensitive sAML blasts, displayed higher messenger RNA and protein expression of TCF7L2, JMJD6, and c-Myc and following BETi washout exhibited rapid restoration of c-Myc and JMJD6. CRISPR/Cas9 knockout of TCF7L2 and JMJD6 depleted their levels, inducing loss of viability of the sAML blasts. Disruption of colocalization of nuclear ß-catenin with TBL1 and TCF7L2 by the small-molecule inhibitor BC2059 combined with depletion of BRD4 by BET proteolysis-targeting chimera reduced c-Myc levels and exerted synergistic lethality in BETi-P/R sAML cells. This combination also reduced leukemia burden and improved survival of mice engrafted with BETi-P/R sAML cells or patient-derived AML blasts innately resistant to BETi. Therefore, multitargeted disruption of the ß-catenin-TCF7L2-JMJD6-c-Myc axis overcomes adaptive and innate BETi resistance, exhibiting preclinical efficacy against human post-MPN sAML cells.


Assuntos
Antineoplásicos/farmacologia , Proteínas de Ciclo Celular/antagonistas & inibidores , Leucemia Mieloide Aguda/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/antagonistas & inibidores , Antineoplásicos/química , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Humanos , Histona Desmetilases com o Domínio Jumonji/metabolismo , Leucemia Mieloide Aguda/metabolismo , Proteólise/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteína 2 Semelhante ao Fator 7 de Transcrição/metabolismo , Fatores de Transcrição/metabolismo , beta Catenina/metabolismo
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