Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 49.049
Filtrar
1.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(2): 450-455, 2021 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-33812414

RESUMO

OBJECTIVE: To investigate the relationship between acute myeloid leukemia (AML) patients ASXL2, ZBTB7A gene mutations and the prognosis. METHODS: 42 AML Patients treated in our hospital from January 2014 to January 2016 were selected and ASXL2 and ZBTB7A genes of their bone marrow samples were sequenced, the genetic characteristics and prognosis of core-binding factor-AML(CBF-AML) patients with ASXL2 and ZBTB7A mutations were analyzed. RESULTS: ASXL2 (33.3%) and ZBTB7A (9.5%) mutations were found in t (8; 21) AML patients. Compared with wild-type, patients with ASXL2 mutations showed significantly higher white blood cell count at diagnosis ï¼»(9.49±1.85)×109/L vs (8.3±1.14)×109/L,P=0.03ï¼½ and lower frequency of sex chromosome deletions (21.43% vs 71.43%, P=0.02), respectively. ASXL2 mutation showed mutually exclusive with ASXL1 mutation (P=0.035). The proportion of chromatin modifier gene ATRX and BCOR mutations was higher in patients with ASXL2 mutation (P=0.032, P=0.005).ASXL2 and ZBTB7A mutations showed no significant effect to overall survival or event-free survival rate in patients with AML. CONCLUSION: ASXL2 and ZBTB7A mutations are frequently found in t (8; 21) AML patients. The mutation of ASXL2 and ZBTB7A genes shows no significant effect on the prognosis of AML patients.


Assuntos
Proteínas de Ligação a DNA , Leucemia Mieloide Aguda , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Humanos , Leucemia Mieloide Aguda/genética , Mutação , Proteínas de Fusão Oncogênica/genética , Prognóstico , Proteínas Repressoras/genética , Fatores de Transcrição/genética
2.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 29(2): 643-647, 2021 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-33812445

RESUMO

Sickle cell disease (SCD) is a single gene genetic disease, which seriously threatens the life span and quality of patients. On the basis of the pathogenesis of SCD and the alternative therapy based on fetal hemoglobin F (HbF), the research progress of transcription factors involved in the regulation of HbF gene expression, such as BCL11A, ZBTB7A, KLF-1, c-MYB and SOX6, as well as the application of CRISPR / Cas9, TALEN, zinc finger nuclease and other gene editing technologies in this field has been made, providing a solid theoretical basis for the exploration of new treatment schemes for ß- like hemoglobin diseases, such as sickle cell disease and ß- thalassemia.


Assuntos
Anemia Falciforme , Hemoglobina Fetal , Anemia Falciforme/genética , Anemia Falciforme/terapia , Linhagem Celular Tumoral , Proteínas de Ligação a DNA , Hemoglobina Fetal/genética , Terapia Genética , Humanos , Proteínas Repressoras/genética , Fatores de Transcrição
3.
Life Sci ; 274: 119327, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33711390

RESUMO

This study aimed to explore the potential target of the cardio-protective effect induced by sevoflurane anesthesia based on evidence from clinical samples and in vitro model. Forty patients undergoing mitral valve replacement were randomly allocated to receive sevoflurane or propofol-based anesthesia. Atrial muscle specimens were collected from all patients, of which 5 were used to perform transcriptomics analysis. The cTn-I concentration was tested before, at the end of, and 24 h after surgery. In in vitro study, the expression level of the identified target gene, i.e., THAP11, was studied in H9C2 cells treated with sevoflurane or propofol. Then, we studied cell viability using CCK-8 staining, apoptosis by using flow cytometry, and cell death by lactic acid dehydrogenase (LDH) detection in H9C2 cells exposed to oxygen glucose deprivation/reoxygenation (OGD/R) injury. THAP11 was the most significantly down-regulated gene in the transcriptomics analysis (P < 0.001), as confirmed in validation samples (P = 0.006). THAP11 mRNA levels in atrial muscle specimens were positively associated with cTn-I levels at 24-h postoperatively (determination coefficient = 0.564; P < 0.001). Sevoflurane treatment down-regulated THAP11 in H9C2 cell models, which promoted cell viability, inhibited cell apoptosis, and death in the OGD/R injury cell model. Up-regulation of THAP11 reduced the protective effect of sevoflurane treatment against OGD/R injury. Sevoflurane anesthesia down-regulates the expression of THAP11, which contributes to a cardio-protective effect. THAP11 down-regulation promotes cell viability, and inhibits cell apoptosis and death, thereby protecting again myocardial injury; it may therefore be a novel target for perioperative cardio-protection.


Assuntos
Cardiotônicos/farmacologia , Insuficiência da Valva Mitral/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Miócitos Cardíacos/efeitos dos fármacos , Proteínas Repressoras/antagonistas & inibidores , Sevoflurano/farmacologia , Anestésicos Inalatórios/farmacologia , Animais , Apoptose , Sobrevivência Celular , Regulação para Baixo , Feminino , Glucose/deficiência , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/etiologia , Insuficiência da Valva Mitral/metabolismo , Insuficiência da Valva Mitral/patologia , Traumatismo por Reperfusão Miocárdica/etiologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Oxigênio/metabolismo , Ratos , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
4.
Nat Commun ; 12(1): 1394, 2021 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-33654093

RESUMO

N6-methyladenosine (m6A) is a reversible mRNA modification that has been shown to play important roles in various biological processes. However, the roles of m6A modification in macrophages are still unknown. Here, we discover that ablation of Mettl3 in myeloid cells promotes tumour growth and metastasis in vivo. In contrast to wild-type mice, Mettl3-deficient mice show increased M1/M2-like tumour-associated macrophage and regulatory T cell infiltration into tumours. m6A sequencing reveals that loss of METTL3 impairs the YTHDF1-mediated translation of SPRED2, which enhances the activation of NF-kB and STAT3 through the ERK pathway, leading to increased tumour growth and metastasis. Furthermore, the therapeutic efficacy of PD-1 checkpoint blockade is attenuated in Mettl3-deficient mice, identifying METTL3 as a potential therapeutic target for tumour immunotherapy.


Assuntos
Adenosina/análogos & derivados , Reprogramação Celular , Macrófagos/metabolismo , Macrófagos/patologia , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , RNA Neoplásico/metabolismo , Adenosina/metabolismo , Animais , Sequência de Bases , Linhagem Celular Tumoral , Polaridade Celular , Proliferação de Células , Citocinas/metabolismo , Deleção de Genes , Regulação da Expressão Gênica , Neoplasias Pulmonares/secundário , Metilação , Metiltransferases/metabolismo , Camundongos Knockout , Células Mieloides/metabolismo , NF-kappa B/metabolismo , Metástase Neoplásica , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas Repressoras , Fator de Transcrição STAT3/metabolismo , Linfócitos T Reguladores/imunologia , Microambiente Tumoral
5.
Nat Genet ; 53(3): 279-287, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33558757

RESUMO

Chromatin accessibility is a hallmark of regulatory regions, entails transcription factor (TF) binding and requires nucleosomal reorganization. However, it remains unclear how dynamic this process is. In the present study, we use small-molecule inhibition of the catalytic subunit of the mouse SWI/SNF remodeler complex to show that accessibility and reduced nucleosome presence at TF-binding sites rely on persistent activity of nucleosome remodelers. Within minutes of remodeler inhibition, accessibility and TF binding decrease. Although this is irrespective of TF function, we show that the activating TF OCT4 (POU5F1) exhibits a faster response than the repressive TF REST. Accessibility, nucleosome depletion and gene expression are rapidly restored on inhibitor removal, suggesting that accessible chromatin is regenerated continuously and in a largely cell-autonomous fashion. We postulate that TF binding to chromatin and remodeler-mediated nucleosomal removal do not represent a stable situation, but instead accessible chromatin reflects an average of a dynamic process under continued renewal.


Assuntos
Cromatina/metabolismo , Complexos Multiproteicos/metabolismo , Fatores de Transcrição/metabolismo , ATPases Associadas a Diversas Atividades Celulares/genética , ATPases Associadas a Diversas Atividades Celulares/metabolismo , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo , Animais , Sítios de Ligação , Linhagem Celular/efeitos dos fármacos , Cromatina/genética , Montagem e Desmontagem da Cromatina/efeitos dos fármacos , Montagem e Desmontagem da Cromatina/fisiologia , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , DNA Helicases/antagonistas & inibidores , DNA Helicases/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Histonas/genética , Histonas/metabolismo , Camundongos , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/efeitos dos fármacos , Complexos Multiproteicos/efeitos dos fármacos , Complexos Multiproteicos/genética , Proteínas Nucleares/antagonistas & inibidores , Proteínas Nucleares/metabolismo , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Receptores Estrogênicos/genética , Receptores Estrogênicos/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologia , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética
6.
Int J Mol Sci ; 22(3)2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33540627

RESUMO

In this study, we found that the loss of OmpR, the response regulator of the two-component EnvZ/OmpR system, increases the cellular level of Fur, the master regulator of iron homeostasis in Y. enterocolitica. Furthermore, we demonstrated that transcription of the fur gene from the YePfur promoter is subject to negative OmpR-dependent regulation. Four putative OmpR-binding sites (OBSs) were indicated by in silico analysis of the fur promoter region, and their removal affected OmpR-dependent fur expression. Moreover, OmpR binds specifically to the predicted OBSs which exhibit a distinct hierarchy of binding affinity. Finally, the data demonstrate that OmpR, by direct binding to the promoters of the fecA, fepA and feoA genes, involved in the iron transport and being under Fur repressor activity, modulates their expression. It seems that the negative effect of OmpR on fecA and fepA transcription is sufficient to counteract the indirect, positive effect of OmpR resulting from decreasing the Fur repressor level. The expression of feoA was positively regulated by OmpR and this mode of action seems to be direct and indirect. Together, the expression of fecA, fepA and feoA in Y. enterocolitica has been proposed to be under a complex mode of regulation involving OmpR and Fur regulators.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Ferro/metabolismo , Proteínas Repressoras/genética , Transativadores/metabolismo , Yersinia enterocolitica/metabolismo , Proteínas da Membrana Bacteriana Externa/genética , Proteínas de Transporte/genética , Simulação por Computador , Homeostase , Proteínas de Ligação ao Ferro/genética , Regiões Promotoras Genéticas , Receptores de Superfície Celular/genética , Yersinia enterocolitica/genética
7.
Int J Mol Sci ; 22(4)2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33557396

RESUMO

HIV-1 infects T cells, but the most frequent AIDS-related lymphomas are of B-cell origin. Molecular mechanisms of HIV-1-induced oncogenic transformation of B cells remain largely unknown. HIV-1 Tat protein may participate in this process by penetrating and regulating gene expression in B cells. Both immune and cancer cells can reprogram communications between extracellular signals and intracellular signaling pathways via the Akt/mTORC1 pathway, which plays a key role in the cellular response to various stimuli including viral infection. Here, we investigated the role of HIV-1 Tat on the modulation of the Akt/mTORC1 pathway in B cells. We found that HIV-1 Tat activated the Akt/mTORC1 signaling pathway; this leads to aberrant activation of activation-induced cytidine deaminase (AICDA) due to inhibition of the AICDA transcriptional repressors c-Myb and E2F8. These perturbations may ultimately lead to an increased genomic instability and proliferation that might cause B cell malignancies.


Assuntos
Linfócitos B/patologia , Citidina Desaminase/metabolismo , Dano ao DNA , Regulação da Expressão Gênica , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Produtos do Gene tat do Vírus da Imunodeficiência Humana/metabolismo , Linfócitos B/imunologia , Linfócitos B/metabolismo , Células Cultivadas , Citidina Desaminase/genética , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-myb/genética , Proteínas Proto-Oncogênicas c-myb/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Ativação Transcricional , Produtos do Gene tat do Vírus da Imunodeficiência Humana/genética
8.
Int J Mol Med ; 47(4): 1, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33537835

RESUMO

Metastasis is the primary cause of the high mortality rates in head and neck squamous cell carcinoma (HNSCC). MicroRNA (miR)­411­5p has been discovered to serve an important role in cancer metastases. However, to the best of our knowledge, the association between miR­411­5p expression levels and HNSCC metastasis has not been thoroughly investigated. The present study aimed to research the function of miR­411­5p in HNSCC metastasis. The results of the present study revealed that miR­411­5p expression levels were upregulated in patients with HNSCC with lymph node metastasis and the upregulated expression levels of miR­411­5p were positively associated with the metastatic potential of HNSCC. Moreover, miR­411­5p promoted HNSCC cell migration, invasion and epithelial­mesenchymal transition (EMT). The results of the dual­luciferase reporter assays identified RING1 and YY1 binding protein (RYBP) as a functional downstream target gene for miR­411­5p. Therefore, whether miR­411­5p downregulated the expression levels of RYBP in HNSCC cells was subsequently investigated. Notably, the silencing of RYBP expression restored the stimulatory effects of miR­411­5p on HNSCC cell migration, invasion and EMT. In addition, the mRNA expression levels of miR­411­5p and RYBP were found to be inversely correlated in HNSCC samples. In conclusion, the results of the present study indicated that the miR­411­5p­mediated downregulation of RYBP expression levels may exert an important role in HNSCC metastasis and may provide a novel target for the treatment of HNSCC.


Assuntos
Metástase Linfática/genética , MicroRNAs/genética , Proteínas Repressoras/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Regulação para Cima/genética , Sequência de Bases , Linhagem Celular Tumoral , Movimento Celular/genética , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Metástase Linfática/patologia , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Invasividade Neoplásica , Metástase Neoplásica , Prognóstico , Proteínas Repressoras/genética
9.
Nat Commun ; 12(1): 1316, 2021 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-33637755

RESUMO

Repeated retroviral infections of vertebrate germlines have made endogenous retroviruses ubiquitous features of mammalian genomes. However, millions of years of evolution obscure many of the immediate repercussions of retroviral endogenisation on host health. Here we examine retroviral endogenisation during its earliest stages in the koala (Phascolarctos cinereus), a species undergoing germline invasion by koala retrovirus (KoRV) and affected by high cancer prevalence. We characterise KoRV integration sites (IS) in tumour and healthy tissues from 10 koalas, detecting 1002 unique IS, with hotspots of integration occurring in the vicinity of known cancer genes. We find that tumours accumulate novel IS, with proximate genes over-represented for cancer associations. We detect dysregulation of genes containing IS and identify a highly-expressed transduced oncogene. Our data provide insights into the tremendous mutational load suffered by the host during active retroviral germline invasion, a process repeatedly experienced and overcome during the evolution of vertebrate lineages.


Assuntos
Células Germinativas , Neoplasias/genética , Infecções por Retroviridae/genética , Retroviridae/genética , Animais , Retrovirus Endógenos , Evolução Molecular , Gammaretrovirus/genética , Regulação Neoplásica da Expressão Gênica , Genoma Humano , Humanos , Neoplasias/virologia , Phascolarctidae/genética , Phascolarctidae/virologia , Proteínas Repressoras/genética , Infecções por Retroviridae/virologia , Proteína bcl-X/genética
10.
Nat Commun ; 12(1): 1022, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33589584

RESUMO

Development of chemoresistance is the main reason for failure of clinical management of multiple myeloma (MM), but the genetic and epigenetic aberrations that interact to confer such chemoresistance remains unknown. In the present study, we find that high steroid receptor coactivator-3 (SRC-3) expression is correlated with relapse/refractory and poor outcomes in MM patients treated with bortezomib (BTZ)-based regimens. Furthermore, in immortalized cell lines, high SRC-3 enhances resistance to proteasome inhibitor (PI)-induced apoptosis. Overexpressed histone methyltransferase NSD2 in patients bearing a t(4;14) translocation or in BTZ-resistant MM cells coordinates elevated SRC-3 by enhancing its liquid-liquid phase separation to supranormally modify histone H3 lysine 36 dimethylation (H3K36me2) modifications on promoters of anti-apoptotic genes. Targeting SRC-3 or interference of its interactions with NSD2 using a newly developed inhibitor, SI-2, sensitizes BTZ treatment and overcomes drug resistance both in vitro and in vivo. Taken together, our findings elucidate a previously unrecognized orchestration of SRC-3 and NSD2 in acquired drug resistance of MM and suggest that SI-2 may be efficacious for overcoming drug resistance in MM patients.


Assuntos
Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Regulação Neoplásica da Expressão Gênica , Histona-Lisina N-Metiltransferase/genética , Mieloma Múltiplo/tratamento farmacológico , Coativador 3 de Receptor Nuclear/genética , Proteínas Repressoras/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Osso e Ossos/patologia , Bortezomib/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cromossomos Humanos Par 14 , Cromossomos Humanos Par 4 , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/genética , Histonas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/genética , Mieloma Múltiplo/mortalidade , Mieloma Múltiplo/patologia , Coativador 3 de Receptor Nuclear/antagonistas & inibidores , Coativador 3 de Receptor Nuclear/metabolismo , Inibidores de Proteassoma/farmacologia , Recidiva , Proteínas Repressoras/metabolismo , Transdução de Sinais , Análise de Sobrevida , Translocação Genética , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Nat Commun ; 12(1): 734, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33531470

RESUMO

Driver genes with a mutually exclusive mutation pattern across tumor genomes are thought to have overlapping roles in tumorigenesis. In contrast, we show here that mutually exclusive prostate cancer driver alterations involving the ERG transcription factor and the ubiquitin ligase adaptor SPOP are synthetic sick. At the molecular level, the incompatible cancer pathways are driven by opposing functions in SPOP. ERG upregulates wild type SPOP to dampen androgen receptor (AR) signaling and sustain ERG activity through degradation of the bromodomain histone reader ZMYND11. Conversely, SPOP-mutant tumors stabilize ZMYND11 to repress ERG-function and enable oncogenic androgen receptor signaling. This dichotomy regulates the response to therapeutic interventions in the AR pathway. While mutant SPOP renders tumor cells susceptible to androgen deprivation therapies, ERG promotes sensitivity to high-dose androgen therapy and pharmacological inhibition of wild type SPOP. More generally, these results define a distinct class of antagonistic cancer drivers and a blueprint toward their therapeutic exploitation.


Assuntos
Proteínas Nucleares/metabolismo , Proteínas Oncogênicas/metabolismo , Neoplasias da Próstata/metabolismo , Proteínas Repressoras/metabolismo , Regulador Transcricional ERG/metabolismo , Complexos Ubiquitina-Proteína Ligase/metabolismo , Animais , Biomarcadores Tumorais/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proteínas Correpressoras/genética , Proteínas Correpressoras/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Células HEK293 , Humanos , Imuno-Histoquímica , Imunoprecipitação , Masculino , Camundongos , Camundongos Nus , Mutação/genética , Proteínas Nucleares/genética , Proteínas Oncogênicas/genética , Neoplasias da Próstata/genética , Ligação Proteica , Proteômica , Receptores Androgênicos/metabolismo , Proteínas Repressoras/genética , Transdução de Sinais/fisiologia , Regulador Transcricional ERG/genética , Complexos Ubiquitina-Proteína Ligase/genética
12.
Nature ; 590(7846): 463-467, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33536618

RESUMO

Actinobacteria produce numerous antibiotics and other specialized metabolites that have important applications in medicine and agriculture1. Diffusible hormones frequently control the production of such metabolites by binding TetR family transcriptional repressors (TFTRs), but the molecular basis for this remains unclear2. The production of methylenomycin antibiotics in Streptomyces coelicolor A3(2) is initiated by the binding of 2-alkyl-4-hydroxymethylfuran-3-carboxylic acid (AHFCA) hormones to the TFTR MmfR3. Here we report the X-ray crystal structure of an MmfR-AHFCA complex, establishing the structural basis for hormone recognition. We also elucidate the mechanism for DNA release upon hormone binding through the single-particle cryo-electron microscopy structure of an MmfR-operator complex. DNA binding and release assays with MmfR mutants and synthetic AHFCA analogues define the role of individual amino acid residues and hormone functional groups in ligand recognition and DNA release. These findings will facilitate the exploitation of actinobacterial hormones and their associated TFTRs in synthetic biology and in the discovery of new antibiotics.


Assuntos
Antibacterianos/biossíntese , Furanos/metabolismo , Streptomyces coelicolor/metabolismo , Apoproteínas/química , Apoproteínas/metabolismo , Apoproteínas/ultraestrutura , Proteínas de Bactérias/química , Proteínas de Bactérias/classificação , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/ultraestrutura , Microscopia Crioeletrônica , Cristalografia por Raios X , DNA/química , DNA/genética , DNA/metabolismo , DNA/ultraestrutura , Furanos/química , Hormônios/química , Hormônios/classificação , Hormônios/metabolismo , Ligantes , Modelos Moleculares , Peptídeos/metabolismo , Proteínas Repressoras/química , Proteínas Repressoras/classificação , Proteínas Repressoras/metabolismo , Proteínas Repressoras/ultraestrutura , Transdução de Sinais , Streptomyces coelicolor/química , Streptomyces coelicolor/genética , Relação Estrutura-Atividade
13.
J Med Chem ; 64(3): 1584-1592, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-33522809

RESUMO

Increased activity of the lysine methyltransferase NSD2 driven by translocation and activating mutations is associated with multiple myeloma and acute lymphoblastic leukemia, but no NSD2-targeting chemical probe has been reported to date. Here, we present the first antagonists that block the protein-protein interaction between the N-terminal PWWP domain of NSD2 and H3K36me2. Using virtual screening and experimental validation, we identified the small-molecule antagonist 3f, which binds to the NSD2-PWWP1 domain with a Kd of 3.4 µM and abrogates histone H3K36me2 binding to the PWWP1 domain in cells. This study establishes an alternative approach to targeting NSD2 and provides a small-molecule antagonist that can be further optimized into a chemical probe to better understand the cellular function of this protein.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Histona-Lisina N-Metiltransferase/antagonistas & inibidores , Proteínas Repressoras/antagonistas & inibidores , Simulação por Computador , Cristalografia por Raios X , Descoberta de Drogas/métodos , Avaliação Pré-Clínica de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Histona-Lisina N-Metiltransferase/efeitos dos fármacos , Humanos , Ligantes , Modelos Moleculares , Simulação de Acoplamento Molecular , Domínios Proteicos , Proteínas Repressoras/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas , Relação Estrutura-Atividade
14.
Ann Hematol ; 100(2): 465-479, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33386934

RESUMO

Additional sex combs like 1 (ASXL1) mutations are one of the most common molecular biological abnormalities in patients with primary myelofibrosis (PMF), and the effect of these mutations on prognosis remains controversial. Hence, we conducted a meta-analysis to assess the prognostic value and clinical characteristics of ASXL1 mutations in PMF patients. Eligible studies were systematically searched from PubMed, Embase, and the Cochrane Library. We extracted the hazard ratios (HRs) and their 95% confidence intervals (CIs) of overall survival (OS) and leukemia-free survival (LFS), the number of patients transformed to acute leukemia, and clinical characteristics to carry out a meta-analysis by fixed effect model or random effect model according to the heterogeneity between studies. A total of 4501 PMF patients from 16 cohorts of 14 studies were included in this meta-analysis. The results revealed that ASXL1 mutations might predict a shorter OS (HR = 2.30, 95% CI: 1.79-2.94, P < 0.00001) and a higher probability of transformation to acute leukemia (LFS: HR = 1.77, 95% CI: 1.30-2.42, P = 0.0003; the rate of acute leukemia transformation: OR = 2.06, 95% CI: 1.50-2.83, P < 0.00001). Furthermore, ASXL1 mutations were correlated with patients older than 65 years old, male, a lower level of platelet counts, and a higher risk of the international prognostic score system. These findings indicate that ASXL1 mutations have a significant adverse impact on the prognosis of PMF patients and may contribute to risk stratification and prognostic assessment for PMF patients.


Assuntos
Carcinogênese/genética , Leucemia , Mutação , Proteínas de Neoplasias/genética , Mielofibrose Primária , Proteínas Repressoras/genética , Doença Aguda , Fatores Etários , Idoso , Intervalo Livre de Doença , Feminino , Humanos , Leucemia/genética , Leucemia/mortalidade , Masculino , Mielofibrose Primária/genética , Mielofibrose Primária/mortalidade , Fatores Sexuais , Taxa de Sobrevida
15.
Int J Mol Sci ; 22(2)2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-33435128

RESUMO

CXC-chemokine receptor type 4 (CXCR4), a 7-transmembrane receptor family member, displays multifaceted roles, participating in immune cell migration, angiogenesis, and even adipocyte metabolism. However, the activity of such a ubiquitously expressed receptor in epithelial gland organogenesis has not yet been fully explored. To investigate the relationship between CXCL12/CXCR4 signaling and embryonic glandular organogenesis, we used an ex vivo culture system with live imaging and RNA sequencing to elucidate the transcriptome and protein-level signatures of AMD3100, a potent abrogating reagent of the CXCR4-CXCL12 axis, imprinted on the developing organs. Immunostaining results showed that CXCR4 was highly expressed in embryonic submandibular gland, lung, and pancreas, especially at the periphery of end buds containing numerous embryonic stem/progenitor cells. Despite no significant increase in apoptosis, AMD3100-treated epithelial organs showed a retarded growth with significantly slower branching and expansion. Further analyses with submandibular glands revealed that such responses resulted from the AMD3100-induced precocious differentiation of embryonic epithelial cells, losing mitotic activity. RNA sequencing analysis revealed that inhibition of CXCR4 significantly down-regulated polycomb repressive complex (PRC) components, known as regulators of DNA methylation. Treatment with PRC inhibitor recapitulated the AMD3100-induced precocious differentiation. Our results indicate that the epigenetic modulation by the PRC-CXCR12/CXCR4 signaling axis is crucial for the spatiotemporal regulation of proliferation and differentiation of embryonic epithelial cells during embryonic glandular organogenesis.


Assuntos
Benzilaminas/farmacologia , Diferenciação Celular , Ciclamos/farmacologia , Receptores CXCR4/metabolismo , Transdução de Sinais , Glândula Submandibular/metabolismo , Animais , Quimiocina CXCL12/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Epigênese Genética , Camundongos , Organogênese , Complexo Repressor Polycomb 1/metabolismo , Complexo Repressor Polycomb 2/metabolismo , Proteínas Repressoras/metabolismo , Glândula Submandibular/efeitos dos fármacos , Glândula Submandibular/embriologia , Glândula Submandibular/fisiologia
16.
Methods Mol Biol ; 2261: 357-379, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33421001

RESUMO

Biotinylation identification (BioID) is a method designed to provide new cellular location and functional knowledge of the protein of interest through the identification of those proteins surrounding and in direct contact. A biotin ligase is fused onto the protein of interest and expressed in cells where it can biotinylate even short-lived transient protein complexes. In addition, due to the proximity labeling nature of the experiment, cellular localization and functional enrichment information can also be obtained. Since labeling occurs only after the addition of biotin, temporal relationships and localization changes (e.g., cytoplasmic to nuclear) can also be identified. Labeled proteins are easily purified, and contaminants minimized, using the strong interaction between biotin and streptavidin. Mass spectrometry analysis of the purified proteins allows for the identification of potential interactors for further validation and characterization.


Assuntos
Carbono-Nitrogênio Ligases/metabolismo , Proteínas de Escherichia coli/metabolismo , Espectrometria de Massas , Mapas de Interação de Proteínas , Proteômica , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Repressoras/metabolismo , Métodos Analíticos de Preparação de Amostras , Animais , Biotinilação , Carbono-Nitrogênio Ligases/genética , Proteínas de Escherichia coli/genética , Células HEK293 , Humanos , Ligação Proteica , Transporte Proteico , Proteínas Recombinantes de Fusão/genética , Proteínas Repressoras/genética , Fatores de Tempo
17.
APMIS ; 129(4): 186-194, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33417719

RESUMO

Syntaxin-1 (STX1) is a recently described highly sensitive and specific neuroendocrine marker. We evaluated the applicability of STX1 as an immunohistochemical marker in pulmonary neuroendocrine neoplasms (NENs). We compared STX1 with established neuroendocrine markers, including insulinoma-associated protein 1 (INSM1). Typical carcinoids (n = 33), atypical carcinoids (n = 7), small cell lung carcinomas ([SCLCs] n = 30), and large cell neuroendocrine lung carcinomas (n = 17) were immunostained using tissue microarray for STX1, chromogranin A, synaptophysin, CD56, and INSM1. Eighty-four of eighty-seven (96.5%) NENs showed STX1 positivity. Carcinoids and LCNECs typically presented a combined strong membranous and weak cytoplasmic staining pattern; cytoplasmic expression was predominately observed in SCLCs. The sensitivity of STX1 was 90% in SCLCs and 100% in typical carcinoids, atypical carcinoids, and large cell neuroendocrine lung carcinomas. The overall sensitivity of STX1 in pulmonary NENs was 96.6%, and the sensitivity of the other markers was as follows: chromogranin A (85.2%), synaptophysin (85.2%), CD56 (92.9%), and INSM1 (97.7%). STX1 was found to be an excellent neuroendocrine marker of pulmonary NENs, with sensitivity and specificity surpassing that of classic markers. We propose a panel of STX1 and INSM1 for the routine immunohistochemical workup of pulmonary NENs.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias Pulmonares/diagnóstico , Tumores Neuroendócrinos/diagnóstico , Proteínas Repressoras/biossíntese , Sintaxina 1/biossíntese , Feminino , Humanos , Masculino , Proteínas Repressoras/análise , Sensibilidade e Especificidade , Sintaxina 1/análise
18.
Nat Immunol ; 22(2): 166-178, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33432227

RESUMO

Type 2 innate lymphoid cells (ILC2) contribute to immune homeostasis, protective immunity and tissue repair. Here we demonstrate that functional ILC2 cells can arise in the embryonic thymus from shared T cell precursors, preceding the emergence of CD4+CD8+ (double-positive) T cells. Thymic ILC2 cells migrated to mucosal tissues, with colonization of the intestinal lamina propria. Expression of the transcription factor RORα repressed T cell development while promoting ILC2 development in the thymus. From RNA-seq, assay for transposase-accessible chromatin sequencing (ATAC-seq) and chromatin immunoprecipitation followed by sequencing (ChIP-seq) data, we propose a revised transcriptional circuit to explain the co-development of T cells and ILC2 cells from common progenitors in the thymus. When Notch signaling is present, BCL11B dampens Nfil3 and Id2 expression, permitting E protein-directed T cell commitment. However, concomitant expression of RORα overrides the repression of Nfil3 and Id2 repression, allowing ID2 to repress E proteins and promote ILC2 differentiation. Thus, we demonstrate that RORα expression represents a critical checkpoint at the bifurcation of the T cell and ILC2 lineages in the embryonic thymus.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Diferenciação Celular , Linhagem da Célula , Imunidade Inata , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Timócitos/metabolismo , Timo/metabolismo , Animais , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Movimento Celular , Células Cultivadas , Técnicas de Cocultura , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Proteína 2 Inibidora de Diferenciação/genética , Proteína 2 Inibidora de Diferenciação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Técnicas de Cultura de Órgãos , Fenótipo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Transdução de Sinais , Timócitos/imunologia , Timo/embriologia , Timo/imunologia , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
19.
Science ; 371(6527)2021 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-33479123

RESUMO

Polycomb repressive complexes 1 and 2 (PRC1 and PRC2) cooperate to determine cell identity by epigenetic gene expression regulation. However, the mechanism of PRC2 recruitment by means of recognition of PRC1-mediated H2AK119ub1 remains poorly understood. Our PRC2 cryo-electron microscopy structure with cofactors JARID2 and AEBP2 bound to a H2AK119ub1-containing nucleosome reveals a bridge helix in EZH2 that connects the SET domain, H3 tail, and nucleosomal DNA. JARID2 and AEBP2 each interact with one ubiquitin and the H2A-H2B surface. JARID2 stimulates PRC2 through interactions with both the polycomb protein EED and the H2AK119-ubiquitin, whereas AEBP2 has an additional scaffolding role. The presence of these cofactors partially overcomes the inhibitory effect that H3K4me3 and H3K36me3 exert on core PRC2 (in the absence of cofactors). Our results support a key role for JARID2 and AEBP2 in the cross-talk between histone modifications and PRC2 activity.


Assuntos
Código das Histonas , Complexo Repressor Polycomb 2/metabolismo , Proteínas Repressoras/metabolismo , Animais , Microscopia Crioeletrônica , Regulação da Expressão Gênica , Histonas/metabolismo , Humanos , Nucleossomos/metabolismo , Domínios PR-SET , Complexo Repressor Polycomb 2/química , Ubiquitina/metabolismo , Xenopus
20.
Am J Hum Genet ; 108(2): 284-294, 2021 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-33421400

RESUMO

Mastocytosis is a rare myeloid neoplasm characterized by uncontrolled expansion of mast cells, driven in >80% of affected individuals by acquisition of the KIT D816V mutation. To explore the hypothesis that inherited variation predisposes to mastocytosis, we performed a two-stage genome-wide association study, analyzing 1,035 individuals with KIT D816V positive disease and 17,960 healthy control individuals from five European populations. After quality control, we tested 592,007 SNPs at stage 1 and 75 SNPs at stage 2 for association by using logistic regression and performed a fixed effects meta-analysis to combine evidence across the two stages. From the meta-analysis, we identified three intergenic SNPs associated with mastocytosis that achieved genome-wide significance without heterogeneity between cohorts: rs4616402 (pmeta = 1.37 × 10-15, OR = 1.52), rs4662380 (pmeta = 2.11 × 10-12, OR = 1.46), and rs13077541 (pmeta = 2.10 × 10-9, OR = 1.33). Expression quantitative trait analyses demonstrated that rs4616402 is associated with the expression of CEBPA (peQTL = 2.3 × 10-14), a gene encoding a transcription factor known to play a critical role in myelopoiesis. The role of the other two SNPs is less clear: rs4662380 is associated with expression of the long non-coding RNA gene TEX41 (peQTL = 2.55 × 10-11), whereas rs13077541 is associated with the expression of TBL1XR1, which encodes transducin (ß)-like 1 X-linked receptor 1 (peQTL = 5.70 × 10-8). In individuals with available data and non-advanced disease, rs4616402 was associated with age at presentation (p = 0.009; beta = 4.41; n = 422). Additional focused analysis identified suggestive associations between mastocytosis and genetic variation at TERT, TPSAB1/TPSB2, and IL13. These findings demonstrate that multiple germline variants predispose to KIT D816V positive mastocytosis and provide novel avenues for functional investigation.


Assuntos
Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Mastocitose/genética , Polimorfismo de Nucleotídeo Único , Proteínas Proto-Oncogênicas c-kit/genética , Sistema y+ de Transporte de Aminoácidos/genética , Proteínas Estimuladoras de Ligação a CCAAT/genética , DNA Intergênico , Feminino , Humanos , Interleucina-13/genética , Íntrons , Masculino , RNA Longo não Codificante/genética , Receptores Citoplasmáticos e Nucleares/genética , Proteínas Repressoras/genética , Telomerase/genética , Triptases/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...