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1.
PLoS Genet ; 16(6): e1008865, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32603360

RESUMO

Fpr1 (FK506-sensitive proline rotamase 1), a protein of the FKBP12 (FK506-binding protein 12 kDa) family in Saccharomyces cerevisiae, is a primary target for the immunosuppressive agents FK506 and rapamycin. Fpr1 inhibits calcineurin and TORC1 (target of rapamycin complex 1) when bound to FK506 and rapamycin, respectively. Although Fpr1 is recognised to play a crucial role in the efficacy of these drugs, its physiological functions remain unclear. In a hmo1Δ (high mobility group family 1-deleted) yeast strain, deletion of FPR1 induced severe growth defects, which could be alleviated by increasing the copy number of RPL25 (ribosome protein of the large subunit 25), suggesting that RPL25 expression was affected in hmo1Δfpr1Δ cells. In the current study, extensive chromatin immunoprecipitation (ChIP) and ChIP-sequencing analyses revealed that Fpr1 associates specifically with the upstream activating sequences of nearly all RPG (ribosomal protein gene) promoters, presumably in a manner dependent on Rap1 (repressor/activator site binding protein 1). Intriguingly, Fpr1 promotes the binding of Fhl1/Ifh1 (forkhead-like 1/interacts with forkhead 1), two key regulators of RPG transcription, to certain RPG promoters independently of and/or cooperatively with Hmo1. Furthermore, mutation analyses of Fpr1 indicated that for transcriptional function on RPG promoters, Fpr1 requires its N-terminal domain and the binding surface for rapamycin, but not peptidyl-prolyl isomerase activity. Notably, Fpr1 orthologues from other species also inhibit TORC1 when bound to rapamycin, but do not regulate transcription in yeast, which suggests that these two functions of Fpr1 are independent of each other.


Assuntos
Proteínas de Grupo de Alta Mobilidade/metabolismo , Peptidilprolil Isomerase/metabolismo , Proteínas Ribossômicas/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Fatores de Transcrição/metabolismo , Calcineurina/metabolismo , Sequenciamento de Cromatina por Imunoprecipitação , Fatores de Transcrição Forkhead/metabolismo , Regulação Fúngica da Expressão Gênica , Genes Fúngicos , Proteínas de Grupo de Alta Mobilidade/genética , Peptidilprolil Isomerase/genética , Regiões Promotoras Genéticas/genética , Ligação Proteica/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/antagonistas & inibidores , Proteínas de Saccharomyces cerevisiae/genética , Sirolimo/farmacologia , Tacrolimo/farmacologia , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética , Transcrição Genética
3.
PLoS One ; 15(7): e0235705, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32649682

RESUMO

Mutations of the SWI/SNF chromatin remodeling complex occur in 20% of all human cancers, including ovarian cancer. Approximately half of ovarian clear cell carcinomas (OCCC) carry mutations in the SWI/SNF subunit ARID1A, while small cell carcinoma of the ovary hypercalcemic type (SCCOHT) presents with inactivating mutations of the SWI/SNF ATPase SMARCA4 alongside epigenetic silencing of the ATPase SMARCA2. Loss of these ATPases disrupts SWI/SNF chromatin remodeling activity and may also interfere with the function of other histone-modifying enzymes that associate with or are dependent on SWI/SNF activity. One such enzyme is lysine-specific histone demethylase 1 (LSD1/KDM1A), which regulates the chromatin landscape and gene expression by demethylating proteins such as histone H3. Cross-cancer analysis of the TCGA database shows that LSD1 is highly expressed in SWI/SNF-mutated tumors. SCCOHT and OCCC cell lines have shown sensitivity to the reversible LSD1 inhibitor SP-2577 (Seclidemstat), suggesting that SWI/SNF-deficient ovarian cancers are dependent on LSD1 activity. Moreover, it has been shown that inhibition of LSD1 stimulates interferon (IFN)-dependent anti-tumor immunity through induction of endogenous retroviral elements and may thereby overcome resistance to checkpoint blockade. In this study, we investigated the ability of SP-2577 to promote anti-tumor immunity and T-cell infiltration in SCCOHT and OCCC cell lines. We found that SP-2577 stimulated IFN-dependent anti-tumor immunity in SCCOHT and promoted the expression of PD-L1 in both SCCOHT and OCCC. Together, these findings suggest that the combination therapy of SP-2577 with checkpoint inhibitors may induce or augment immunogenic responses of SWI/SNF-mutated ovarian cancers and warrants further investigation.


Assuntos
Antineoplásicos/farmacologia , Proteínas Cromossômicas não Histona/genética , Proteínas de Ligação a DNA/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Linfócitos T/efeitos dos fármacos , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Carcinoma de Células Pequenas/genética , Carcinoma de Células Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Meios de Cultivo Condicionados/química , Meios de Cultivo Condicionados/farmacologia , DNA Helicases/genética , DNA Helicases/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Histonas/genética , Histonas/metabolismo , Humanos , Interferons/farmacologia , Mutação , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/patologia , Linfócitos T/citologia , Linfócitos T/imunologia , Fatores de Transcrição/metabolismo
4.
SAR QSAR Environ Res ; 31(7): 547-570, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32657160

RESUMO

It is well known that bromodomain-containing protein 4 (BRD4) has been thought as a promising target utilized for treating various human diseases, such as inflammatory disorders, malignant tumours, acute myelogenous leukaemia (AML), bone diseases, etc. For this study, molecular dynamics (MD) simulations, binding free energy calculations, and principal component analysis (PCA) were integrated together to uncover binding modes of inhibitors 8P9, 8PU, and 8PX to BRD4(1). The results obtained from binding free energy calculations show that van der Waals interactions act as the main regulator in bindings of inhibitors to BRD4(1). The information stemming from PCA reveals that inhibitor associations extremely affect conformational changes, internal dynamics, and movement patterns of BRD4(1). Residue-based free energy decomposition method was wielded to unveil contributions of independent residues to inhibitor bindings and the data signify that hydrogen bonding interactions and hydrophobic interactions are decisive factors affecting bindings of inhibitors to BRD4(1). Meanwhile, eight residues Trp81, Pro82, Val87, Leu92, Leu94, Cys136, Asn140, and Ile146 are recognized as the common hot interaction spots of three inhibitors with BRD4(1). The results from this work are expected to provide a meaningfully theoretical guidance for design and development of effective inhibitors inhibiting of the activity of BRD4.


Assuntos
Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/química , Simulação de Dinâmica Molecular , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/química , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Análise de Componente Principal , Ligação Proteica
5.
SAR QSAR Environ Res ; 31(5): 373-398, 2020 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-32496901

RESUMO

Emerging evidences indicate bromodomain-containing proteins 2 and 4 (BRD2 and BRD4) play critical roles in cancers, inflammations, cardiovascular diseases and other pathologies. Multiple short molecular dynamics (MSMD) simulations combined with molecular mechanics generalized Born surface area (MM-GBSA) method were applied to investigate the binding selectivity of three inhibitors 87D, 88M and 89G towards BRD2 over BRD4. The root-mean-square fluctuation (RMSF) analysis indicates that the structural flexibility of BRD4 is stronger than that of BRD2. Moreover the calculated distances between the Cα atoms in the centres of the ZA_loop and BC_loop of BRD4 are also bigger than that of BRD2. The rank of binding free energies calculated using MM-GBSA method agrees well with that determined by experimental data. The results show that 87D can bind more favourably to BRD2 than BRD4, while 88M has better selectivity on BRD4 over BRD2. Residue-based free-energy decomposition method was utilized to estimate the inhibitor-residue interaction spectrum and the results not only identify the hot interaction spots of inhibitors with BRD2 and BRD4, but also demonstrate that several common residues, including (W370, W374), (P371, P375), (V376, V380) and (L381, L385) belonging to (BRD2, BRD4), generate significant binding difference of inhibitors to BRD2 and BRD4.


Assuntos
Proteínas de Ciclo Celular/antagonistas & inibidores , Simulação de Dinâmica Molecular , Fatores de Transcrição/antagonistas & inibidores , Proteínas de Ciclo Celular/química , Ligação Proteica , Fatores de Transcrição/química
6.
Nat Commun ; 11(1): 2639, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32457312

RESUMO

Homologous recombination (HR) is important for error-free DNA double strand break repair and maintenance of genomic stability. However, upregulated HR is also used by cancer cells to promote therapeutic resistance. Therefore, inducing HR deficiency (HRD) is a viable strategy to sensitize HR proficient cancers to DNA targeted therapies in order to overcome therapeutic resistance. A bromodomain containing protein, BRD9, was previously reported to regulate chromatin remodeling and transcription. Here, we discover that following DNA damage, the bromodomain of BRD9 binds acetylated K515 on RAD54 and facilitates RAD54's interaction with RAD51, which is essential for HR. BRD9 is overexpressed in ovarian cancer and depleting BRD9 sensitizes cancer cells to olaparib and cisplatin. In addition, inhibitor of BRD9, I-BRD9, acts synergistically with olaparib in HR-proficient cancer cells. Overall, our results elucidate a role for BRD9 in HR and identify BRD9 as a potential therapeutic target to promote synthetic lethality and overcome chemoresistance.


Assuntos
DNA Helicases/metabolismo , Proteínas de Ligação a DNA/metabolismo , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Rad51 Recombinase/metabolismo , Reparo de DNA por Recombinação , Fatores de Transcrição/metabolismo , Animais , Linhagem Celular Tumoral , Cisplatino/administração & dosagem , DNA Helicases/química , DNA Helicases/genética , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Técnicas de Silenciamento de Genes , Instabilidade Genômica , Xenoenxertos , Humanos , Camundongos , Camundongos Nus , Complexos Multiproteicos/química , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Ftalazinas/administração & dosagem , Piperazinas/administração & dosagem , Domínios e Motivos de Interação entre Proteínas , Rad51 Recombinase/química , Rad51 Recombinase/genética , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética
7.
Gene ; 753: 144807, 2020 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-32461017

RESUMO

Mitochondrial transcription factor A (TFAM), which is required for mitochondrial DNA (mtDNA) transcription, has been linked to metabolic changes that contribute to tumorigenesis and chemoresistance. In this work, we investigated the expression pattern and role of TFAM in hepatocellular carcinoma (HCC). TFAM expression level is similar in 18 out of 20 paired normal liver and HCC tissues with only 2 HCC tissues showing 1.8-fold increase in TFAM. Similar phenomenon was observed in HCC cell lines compared to normal liver lines. Interestingly, TFAM expression is upregulated in resistant HCC cells regardless of the differential TFAM expression level in their parental lines and mechanism of resistance. TFAM depletion led to inhibition of growth and survival but not migration, and sensitization to doxorubicin and sorafenib treatment, through AMPK activation, reduction of nucleoside triphosphates and mitochondrial respiration in HCC cells. In addition, we demonstrated that resistant HCC cell lines were more sensitive to TFAM inhibition than parental lines, and this might be due to the increased mitochondrial biogenesis in resistant HCC cell lines. Our work reveals the preferential role of TFAM in HCC cell response to standard of care drugs, which suggests a potential sensitizing therapeutic target for HCC treatment.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Carcinoma Hepatocelular/tratamento farmacológico , Proteínas de Ligação a DNA/deficiência , Doxorrubicina/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Mitocôndrias/metabolismo , Proteínas Mitocondriais/deficiência , Sorafenibe/farmacologia , Fatores de Transcrição/deficiência , Proteínas Quinases Ativadas por AMP/genética , Adulto , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Transformação Celular Neoplásica , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Mitocôndrias/genética , Proteínas Mitocondriais/antagonistas & inibidores , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Regulação para Cima
8.
PLoS Genet ; 16(4): e1008583, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32236127

RESUMO

The precise control of eye size is essential for normal vision. TMEM98 is a highly conserved and widely expressed gene which appears to be involved in eye size regulation. Mutations in human TMEM98 are found in patients with nanophthalmos (very small eyes) and variants near the gene are associated in population studies with myopia and increased eye size. As complete loss of function mutations in mouse Tmem98 result in perinatal lethality, we produced mice deficient for Tmem98 in the retinal pigment epithelium (RPE), where Tmem98 is highly expressed. These mice have greatly enlarged eyes that are very fragile with very thin retinas, compressed choroid and thin sclera. To gain insight into the mechanism of action we used a proximity labelling approach to discover interacting proteins and identified MYRF as an interacting partner. Mutations of MYRF are also associated with nanophthalmos. The protein is an endoplasmic reticulum-tethered transcription factor which undergoes autoproteolytic cleavage to liberate the N-terminal part which then translocates to the nucleus where it acts as a transcription factor. We find that TMEM98 inhibits the self-cleavage of MYRF, in a novel regulatory mechanism. In RPE lacking TMEM98, MYRF is ectopically activated and abnormally localised to the nuclei. Our findings highlight the importance of the interplay between TMEM98 and MYRF in determining the size of the eye.


Assuntos
Olho/anatomia & histologia , Olho/metabolismo , Proteínas de Membrana/metabolismo , Fatores de Transcrição/antagonistas & inibidores , Animais , Eletrorretinografia , Anormalidades do Olho/genética , Feminino , Deleção de Genes , Mutação com Perda de Função , Masculino , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Tamanho do Órgão/genética , Ligação Proteica , Transporte Proteico , Epitélio Pigmentado da Retina/anormalidades , Epitélio Pigmentado da Retina/metabolismo , Retinaldeído/metabolismo , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
9.
Nat Commun ; 11(1): 1833, 2020 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-32286255

RESUMO

Small molecule inhibitor of the bromodomain and extraterminal domain (BET) family proteins is a promising option for cancer treatment. However, current BET inhibitors are limited by their potency or oral bioavailability. Here we report the discovery and characterization of NHWD-870, a BET inhibitor that is more potent than three major clinical stage BET inhibitors BMS-986158, OTX-015, and GSK-525762. NHWD-870 causes tumor shrinkage or significantly suppresses tumor growth in nine xenograft or syngeneic models. In addition to its ability to downregulate c-MYC and directly inhibit tumor cell proliferation, NHWD-870 blocks the proliferation of tumor associated macrophages (TAMs) through multiple mechanisms, partly by reducing the expression and secretion of macrophage colony-stimulating factor CSF1 by tumor cells. NHWD-870 inhibits CSF1 expression through suppressing BRD4 and its target HIF1α. Taken together, these results reveal a mechanism by which BRD4 inhibition suppresses tumor growth, and support further development of NHWD-870 to treat solid tumors.


Assuntos
Comunicação Celular , Proteínas de Ciclo Celular/antagonistas & inibidores , Macrófagos/patologia , Neoplasias/patologia , Fatores de Transcrição/antagonistas & inibidores , Administração Oral , Animais , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Modelos Animais de Doenças , Regulação para Baixo , Desenho de Fármacos , Feminino , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Fator Estimulador de Colônias de Macrófagos/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus , Fosforilação , Proteínas Proto-Oncogênicas c-myc/metabolismo , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo , Resultado do Tratamento
10.
PLoS One ; 15(3): e0230670, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32231397

RESUMO

The human positive coactivator 4 (PC4) was originally identified as a multi-functional cofactor capable of mediating transcription activation by diverse gene- and tissue-specific activators. Recent studies suggest that PC4 might also function as a novel cancer biomarker and therapeutic target for different types of cancers. siRNA knockdown studies indicated that down-regulation of PC4 expression could inhibit tumorigeneicity of A549 non-small cell lung cancer tumor model in nude mice. Here we show that AG-1031, a small molecule identified by high throughput screening, can inhibit the double-stranded DNA binding activity of PC4, more effectively than its single-stranded DNA binding activity. AG-1031 also specifically inhibited PC4-dependent transcriptional activation in vitro using purified transcription factors. AG-1031 inhibited proliferation of several cultured cell lines derived from non-small cell lung cancers (NSCLC) and growth of tumors that formed from A549 cell xenografts in immuno-compromised mice. Moreover, pre-injection of AG-1031 in these mice not only reduced tumor size, but also prevented tumor formation in 20% of the animals. AG-1031 treated A549 cells and tumors from AG-1031 treated animals showed a significant decrease in the levels of both PC4 and VEGFC, a key mediator of angiogenesis in cancer. On the other hand, all tested mice remained constant weight during animal trials. These results demonstrated that AG-1031 could be a potential therapy for PC4-positive NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Proteínas de Ligação a DNA/antagonistas & inibidores , Neoplasias Pulmonares/tratamento farmacológico , Compostos Orgânicos/uso terapêutico , Fatores de Transcrição/antagonistas & inibidores , Células A549 , Animais , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/efeitos dos fármacos , DNA/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Humanos , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Nus , Compostos Orgânicos/farmacologia , Ligação Proteica , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcrição Genética/efeitos dos fármacos , Transplante Heterólogo , Fator C de Crescimento do Endotélio Vascular/metabolismo
11.
Nat Commun ; 11(1): 1935, 2020 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-32321921

RESUMO

Although cellular senescence acts primarily as a tumour suppression mechanism, the accumulation of senescent cells in vivo eventually exerts deleterious side effects through inflammatory/tumour-promoting factor secretion. Thus, the development of new drugs that cause the specific elimination of senescent cells, termed senolysis, is anticipated. Here, by an unbiased high-throughput screening of chemical compounds and a bio-functional analysis, we identify BET family protein degrader (BETd) as a promising senolytic drug. BETd provokes senolysis through two independent but integrated pathways; the attenuation of non-homologous end joining (NHEJ), and the up-regulation of autophagic gene expression. BETd treatment eliminates senescent hepatic stellate cells in obese mouse livers, accompanied by the reduction of liver cancer development. Furthermore, the elimination of chemotherapy-induced senescent cells by BETd increases the efficacy of chemotherapy against xenograft tumours in immunocompromised mice. These results reveal the vulnerability of senescent cells and open up possibilities for its control.


Assuntos
Antineoplásicos/administração & dosagem , Autofagia/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Reparo do DNA por Junção de Extremidades/efeitos dos fármacos , Neoplasias/fisiopatologia , Animais , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/metabolismo , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
12.
Science ; 368(6489): 387-394, 2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-32193360

RESUMO

The two tandem bromodomains of the BET (bromodomain and extraterminal domain) proteins enable chromatin binding to facilitate transcription. Drugs that inhibit both bromodomains equally have shown efficacy in certain malignant and inflammatory conditions. To explore the individual functional contributions of the first (BD1) and second (BD2) bromodomains in biology and therapy, we developed selective BD1 and BD2 inhibitors. We found that steady-state gene expression primarily requires BD1, whereas the rapid increase of gene expression induced by inflammatory stimuli requires both BD1 and BD2 of all BET proteins. BD1 inhibitors phenocopied the effects of pan-BET inhibitors in cancer models, whereas BD2 inhibitors were predominantly effective in models of inflammatory and autoimmune disease. These insights into the differential requirement of BD1 and BD2 for the maintenance and induction of gene expression may guide future BET-targeted therapies.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos/farmacologia , Proteínas de Ciclo Celular/antagonistas & inibidores , Histona Acetiltransferases/antagonistas & inibidores , Fatores Imunológicos/farmacologia , Terapia de Alvo Molecular , Fatores de Transcrição/antagonistas & inibidores , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/uso terapêutico , Antineoplásicos/uso terapêutico , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/genética , Descoberta de Drogas , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Histona Acetiltransferases/química , Histona Acetiltransferases/genética , Humanos , Doenças do Sistema Imunitário/tratamento farmacológico , Fatores Imunológicos/química , Fatores Imunológicos/uso terapêutico , Inflamação/tratamento farmacológico , Neoplasias/tratamento farmacológico , Domínios Proteicos/efeitos dos fármacos , Fatores de Transcrição/química , Fatores de Transcrição/genética
13.
Phytomedicine ; 69: 153210, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32217447

RESUMO

BACKGROUND: More than 80% of advanced prostate cancer (PCa) cases have bone metastasis, with a 5-year survival rate of 25%. Previously, we reported that GRT, a standardized, pharmaceutical-grade aspalathin-rich extract (12.78 g aspalathin/100 g extract), prepared from green rooibos produced from the leaves and fine stems of Aspalathus linearis, inhibits the proliferation of PCa cells, meriting this investigation to determine if GRT can suppress the migration and invasion of castration-resistant prostate cancer (CRPC) cells. PURPOSE: In the present study, we investigated whether GRT extract can interfere with the migration and invasion of human CRPC cells. METHODS: Transwell assays were used to explore the effects of GRT on the migration and invasion of CRPC cells. Micro-Western Array (MWA) and Western blot analysis were carried out to unravel the underlying molecular mechanism(s). RESULTS: Treatment with 25-100 µg/ml GRT suppressed the migration and invasion of LNCaP C4-2B and 22Rv1 CRPC cells. MWA and Western blot analysis indicated that GRT treatment suppressed the protein level of yes-associated protein (YAP), macrophage stimulating 1 protein (MST1), phospho-MST1/phospho-MST2 T183/T180, and paxillin, but increased the abundance of E-cadherin. Over-expression of YAP rescued the suppressive effects of GRT on migration and invasion of CRPC cells. Treatment with the major flavonoid of GRT - the C-glucosyl dihydrochalcone, aspalathin - at a concentration of 75-100 µg/ml also reduced the migration and invasion of CRPC cells, and the inhibition was partially rescued by YAP over-expression. CONCLUSIONS: GRT treatment suppresses the migration and invasion of CRPC cells via inhibition of YAP signaling and paxillin.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Aspalathus/química , Chalconas/farmacologia , Extratos Vegetais/farmacologia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Antineoplásicos Fitogênicos/química , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Humanos , Masculino , Paxilina/metabolismo , Extratos Vegetais/química , Neoplasias de Próstata Resistentes à Castração/patologia , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo
14.
J Med Chem ; 63(7): 3678-3700, 2020 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-32153186

RESUMO

Bromodomain-containing protein 4 (BRD4) and histone deacetylases (HDAC) are both attractive epigenetic targets in cancer and other chronic diseases. Based on the integrated fragment-based drug design, synthesis, and in vitro and in vivo evaluations, a series of novel thieno[2,3-d]pyrimidine-based hydroxamic acid derivatives are discovered as selective BRD4-HDAC dual inhibitors. Compound 17c is the most potent inhibitor for BRD4 and HDAC with IC50 values at nanomolar levels, as well as the expression level of c-Myc, and increases the acetylation of histone H3. Moreover, 17c presents inhibitory effects on the proliferation of colorectal carcinoma (CRC) cells via inducing autophagic cell death. It also has a good pharmacokinetic profile in rats and oral bioavailability of 40.5%. In the HCT-116 xenograft in vivo models, 17c displays potent inhibitory efficiency on tumor growth by inducing autophagic cell death and suppressing IL6-JAK-STAT signaling pathways. Our results suggest that the BRD4-HDAC dual inhibition might be an attractive therapeutic strategy for CRC.


Assuntos
Antineoplásicos/uso terapêutico , Autofagia/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Inibidores de Histona Desacetilases/uso terapêutico , Ácidos Hidroxâmicos/uso terapêutico , Animais , Antineoplásicos/síntese química , Antineoplásicos/metabolismo , Apoptose/efeitos dos fármacos , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Inibidores de Histona Desacetilases/síntese química , Inibidores de Histona Desacetilases/metabolismo , Histona Desacetilases/metabolismo , Humanos , Ácidos Hidroxâmicos/síntese química , Ácidos Hidroxâmicos/metabolismo , Masculino , Simulação de Acoplamento Molecular , Estrutura Molecular , Pirimidinas/síntese química , Pirimidinas/metabolismo , Pirimidinas/uso terapêutico , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade , Tiofenos/síntese química , Tiofenos/metabolismo , Tiofenos/uso terapêutico , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Peixe-Zebra
15.
J Med Chem ; 63(8): 3956-3975, 2020 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-32208600

RESUMO

The bromodomain and extra-terminal (BET) family proteins have recently emerged as promising drug targets for cancer therapy. In this study, identification of an 8-methyl-pyrrolo[1,2-a]pyrazin-1(2H)-one fragment (47) as a new binder to the BET bromodomains and the subsequent incorporation of fragment 47 to the scaffold of ABBV-075, which recently entered Phase I clinical trials, enabled the generation of a series of highly potent BET bromodomain inhibitors. Further druggability optimization led to the discovery of compound 38 as a potential preclinical candidate. Significantly, compared with ABBV-075, which exhibits a 63-fold selectivity for BRD4(1) over EP300, compound 38 demonstrates an excellent selectivity for the BET bromodomain family over other bromodomains, with an ∼1500-fold selectivity for BRD4(1) over EP300. Orally administered 38 achieves a complete inhibition of tumor growth with a tumor growth inhibition (TGI) of 99.7% accompanied by good tolerability.


Assuntos
Acetanilidas/química , Acetanilidas/farmacologia , Proteínas de Ciclo Celular/antagonistas & inibidores , Descoberta de Drogas/métodos , Compostos Heterocíclicos com 3 Anéis/química , Compostos Heterocíclicos com 3 Anéis/farmacologia , Piridonas/química , Piridonas/farmacologia , Sulfonamidas/química , Sulfonamidas/farmacologia , Fatores de Transcrição/antagonistas & inibidores , Animais , Proteínas de Ciclo Celular/metabolismo , Cães , Relação Dose-Resposta a Droga , Proteína p300 Associada a E1A/antagonistas & inibidores , Proteína p300 Associada a E1A/metabolismo , Haplorrinos , Humanos , Camundongos , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Domínios Proteicos/efeitos dos fármacos , Domínios Proteicos/fisiologia , Estrutura Secundária de Proteína , Ratos , Relação Estrutura-Atividade , Fatores de Transcrição/metabolismo
16.
J Med Chem ; 63(6): 3227-3237, 2020 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-32091206

RESUMO

Inhibition of the bromodomain containing protein 9 (BRD9) by small molecules is an attractive strategy to target mutated SWI/SNF chromatin-remodeling complexes in cancer. However, reported BRD9 inhibitors also inhibit the closely related bromodomain-containing protein 7 (BRD7), which has different biological functions. The structural basis for differential potency and selectivity of BRD9 inhibitors is largely unknown because of the lack of structural information on BRD7. Here, we biochemically and structurally characterized diverse inhibitors with varying degrees of potency and selectivity for BRD9 over BRD7. Novel cocrystal structures of BRD7 liganded with new and previously reported inhibitors of five different chemical scaffolds were determined alongside BRD9 and BRD4. We also report the discovery of first-in-class dual bromodomain-kinase inhibitors outside the bromodomain and extraterminal family targeting BRD7 and BRD9. Combined, the data provide a new framework for the development of BRD7/9 inhibitors with improved selectivity or additional polypharmacologic properties.


Assuntos
Proteínas Cromossômicas não Histona/antagonistas & inibidores , Compostos Heterocíclicos com 2 Anéis/química , Domínios Proteicos/efeitos dos fármacos , Fatores de Transcrição/antagonistas & inibidores , Sítios de Ligação , Calorimetria/métodos , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/metabolismo , Proteínas Cromossômicas não Histona/metabolismo , Cristalografia por Raios X , Fluorometria/métodos , Compostos Heterocíclicos com 2 Anéis/metabolismo , Humanos , Ligantes , Estrutura Molecular , Ligação Proteica , Relação Estrutura-Atividade , Fatores de Transcrição/metabolismo
17.
Proc Natl Acad Sci U S A ; 117(9): 4770-4780, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32071245

RESUMO

Recurrence and metastasis remain the major obstacles to successful treatment of hepatocellular carcinoma (HCC). Chromatin remodeling factor ARID2 is commonly mutated in HCC, indicating its important role in cancer development. However, its role in HCC metastasis is largely elusive. In this study, we find that ARID2 expression is significantly decreased in metastatic HCC tissues, showing negative correlation with pathological grade, organ metastasis and positive association with survival of HCC patients. ARID2 inhibits migration and invasion of HCC cells in vitro and metastasis in vivo. Moreover, ARID2 knockout promotes pulmonary metastasis in different HCC mouse models. Mechanistic study reveals that ARID2 represses epithelial-mesenchymal transition (EMT) of HCC cells by recruiting DNMT1 to Snail promoter, which increases promoter methylation and inhibits Snail transcription. In addition, we discover that ARID2 mutants with disrupted C2H2 domain lose the metastasis suppressor function, exhibiting a positive association with HCC metastasis and poor prognosis. In conclusion, our study reveals the metastasis suppressor role as well as the underlying mechanism of ARID2 in HCC and provides a potential therapeutic target for ARID2-deficient HCC.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Montagem e Desmontagem da Cromatina/fisiologia , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Metástase Neoplásica/tratamento farmacológico , Fatores de Transcrição/metabolismo , Animais , Dedos de Zinco CYS2-HIS2 , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Modelos Animais de Doenças , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Knockout , Mutação , Metástase Neoplásica/patologia , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/genética
18.
Cancer Sci ; 111(4): 1058-1064, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32073717

RESUMO

Dysregulation or mutation of DNA binding proteins such as transcription factors (TFs) is associated with the onset and progression of various types of disease, including cancer. Alteration of TF activity occurs in numerous cancer tissues due to gene amplification, deletion, and point mutations, and epigenetic modification. Although cancer-associated TFs are promising targets for cancer therapy, development of drugs targeting these TFs has historically been difficult due to the lack of high-throughput screening methods. Recent advances in technology for identification and selective inhibition of DNA binding proteins enable cancer researchers to develop novel therapeutics targeting cancer-associated TFs. In the present review, we summarize known cancer-associated TFs according to cancer type and introduce recently developed high-throughput approaches to identify selective inhibitors of cancer-associated TFs.


Assuntos
Proteínas de Ligação a DNA/genética , Terapia de Alvo Molecular , Neoplasias/genética , Fatores de Transcrição/genética , Sítios de Ligação/genética , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/uso terapêutico , Epigênese Genética/genética , Humanos , Neoplasias/terapia , Ligação Proteica/efeitos dos fármacos , Fatores de Transcrição/antagonistas & inibidores , Fatores de Transcrição/uso terapêutico
19.
Nat Commun ; 11(1): 740, 2020 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-32029739

RESUMO

Primary and acquired drug resistance imposes a major threat to achieving optimized clinical outcomes during cancer treatment. Aberrant changes in epigenetic modifications are closely involved in drug resistance of tumor cells. Using BET inhibitor (BETi) resistant leukemia cells as a model system, we demonstrated herein that genome-wide enhancer remodeling played a pivotal role in driving therapeutic resistance via compensational re-expression of pro-survival genes. Capitalizing on the CRISPR interference technology, we identified the second intron of IncRNA, PVT1, as a unique bona fide gained enhancer that restored MYC transcription independent of BRD4 recruitment in leukemia. A combined BETi and CDK7 inhibitor treatment abolished MYC transcription by impeding RNAPII loading without affecting PVT1-mediated chromatin looping at the MYC locus in BETi-resistant leukemia cells. Together, our findings have established the feasibility of targeting enhancer plasticity to overcome drug resistance associated with epigenetic therapies.


Assuntos
Leucemia Experimental/tratamento farmacológico , Leucemia Experimental/genética , Proteínas Nucleares/antagonistas & inibidores , Fatores de Transcrição/antagonistas & inibidores , Animais , Proteínas de Ciclo Celular/antagonistas & inibidores , Linhagem Celular Tumoral , Quinases Ciclina-Dependentes/antagonistas & inibidores , Resistencia a Medicamentos Antineoplásicos/genética , Sinergismo Farmacológico , Elementos Facilitadores Genéticos , Feminino , Genes myc/efeitos dos fármacos , Compostos Heterocíclicos de 4 ou mais Anéis/administração & dosagem , Humanos , Células Jurkat , Células K562 , Leucemia Experimental/metabolismo , Camundongos , Modelos Genéticos , Fenilenodiaminas/administração & dosagem , Pirimidinas/administração & dosagem , RNA Polimerase II/metabolismo , RNA Longo não Codificante/genética
20.
Nucleic Acids Res ; 48(3): 1583-1598, 2020 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-31956908

RESUMO

Cyclic dimeric 3'-5' guanosine monophosphate, c-di-GMP, is a ubiquitous second messenger controlling diverse cellular processes in bacteria. In streptomycetes, c-di-GMP plays a crucial role in a complex morphological differentiation by modulating an activity of the pleiotropic regulator BldD. Here we report that c-di-GMP plays a key role in regulating secondary metabolite production in streptomycetes by altering the expression levels of bldD. Deletion of cdgB encoding a diguanylate cyclase in Streptomycesghanaensis reduced c-di-GMP levels and the production of the peptidoglycan glycosyltransferase inhibitor moenomycin A. In contrast to the cdgB mutant, inactivation of rmdB, encoding a phosphodiesterase for the c-di-GMP hydrolysis, positively correlated with the c-di-GMP and moenomycin A accumulation. Deletion of bldD adversely affected the synthesis of secondary metabolites in S. ghanaensis, including the production of moenomycin A. The bldD-deficient phenotype is partly mediated by an increase in expression of the pleiotropic regulatory gene wblA. Genetic and biochemical analyses demonstrate that a complex of c-di-GMP and BldD effectively represses transcription of wblA, thus preventing sporogenesis and sustaining antibiotic synthesis. These results show that manipulation of the expression of genes controlling c-di-GMP pool has the potential to improve antibiotic production as well as activate the expression of silent gene clusters.


Assuntos
Proteínas de Bactérias/genética , Bambermicinas/biossíntese , Produtos Biológicos/metabolismo , GMP Cíclico/análogos & derivados , Proteínas de Ligação a DNA/genética , Fatores de Transcrição/genética , Proteínas de Bactérias/antagonistas & inibidores , GMP Cíclico/genética , GMP Cíclico/metabolismo , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Escherichia coli/genética , Deleção de Genes , Regulação Bacteriana da Expressão Gênica/genética , Nucleotídeos/genética , Peptidoglicano Glicosiltransferase/antagonistas & inibidores , Fósforo-Oxigênio Liases/genética , Sistemas do Segundo Mensageiro/genética , Streptomycetaceae/genética , Streptomycetaceae/metabolismo , Fatores de Transcrição/antagonistas & inibidores
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