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1.
Blood ; 132(14): 1507-1518, 2018 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-30104217

RESUMO

Adult T-cell leukemia lymphoma (ATLL) is a rare T cell neoplasm that is endemic in Japanese, Caribbean, and Latin American populations. Most North American ATLL patients are of Caribbean descent and are characterized by high rates of chemo-refractory disease and worse prognosis compared with Japanese ATLL. To determine genomic differences between these 2 cohorts, we performed targeted exon sequencing on 30 North American ATLL patients and compared the results with the Japanese ATLL cases. Although the frequency of TP53 mutations was comparable, the mutation frequency in epigenetic and histone modifying genes (57%) was significantly higher, whereas the mutation frequency in JAK/STAT and T-cell receptor/NF-κB pathway genes was significantly lower. The most common type of epigenetic mutation is that affecting EP300 (20%). As a category, epigenetic mutations were associated with adverse prognosis. Dissimilarities with the Japanese cases were also revealed by RNA sequencing analysis of 9 primary patient samples. ATLL samples with a mutated EP300 gene have decreased total and acetyl p53 protein and a transcriptional signature reminiscent of p53-mutated cancers. Most importantly, decitabine has highly selective single-agent activity in the EP300-mutated ATLL samples, suggesting that decitabine treatment induces a synthetic lethal phenotype in EP300-mutated ATLL cells. In conclusion, we demonstrate that North American ATLL has a distinct genomic landscape that is characterized by frequent epigenetic mutations that are targetable preclinically with DNA methyltransferase inhibitors.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Decitabina/uso terapêutico , Leucemia-Linfoma de Células T do Adulto/tratamento farmacológico , Leucemia-Linfoma de Células T do Adulto/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose/efeitos dos fármacos , Proteína p300 Associada a E1A/genética , Epigênese Genética , Feminino , Humanos , Japão/epidemiologia , Leucemia-Linfoma de Células T do Adulto/diagnóstico , Leucemia-Linfoma de Células T do Adulto/epidemiologia , Masculino , Pessoa de Meia-Idade , Taxa de Mutação , Prognóstico , Transcriptoma , Proteína Supressora de Tumor p53/genética , Estados Unidos/epidemiologia
2.
J Pharmacol Exp Ther ; 366(3): 458-469, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29945930

RESUMO

Previous evidence has suggested that puerarin may attenuate cardiac hypertrophy; however, the potential mechanisms have not been determined. Moreover, the use of puerarin is limited by severe adverse events, including intravascular hemolysis. This study used a rat model of abdominal aortic constriction (AAC)-induced cardiac hypertrophy to evaluate the potential mechanisms underlying the attenuating efficacy of puerarin on cardiac hypertrophy, as well as the metabolic mechanisms of puerarin involved. We confirmed that puerarin (50 mg/kg per day) significantly attenuated cardiac hypertrophy, upregulated Nrf2, and decreased Keap1 in the myocardium. Moreover, puerarin significantly promoted Nrf2 nuclear accumulation in parallel with the upregulated downstream proteins, including heme oxygenase 1, glutathione transferase P1, and NAD(P)H:quinone oxidoreductase 1. Similar results were obtained in neonatal rat cardiomyocytes (NRCMs) treated with angiotensin II (Ang II; 1 µM) and puerarin (100 µM), whereas the silencing of Nrf2 abolished the antihypertrophic effects of puerarin. The mRNA and protein levels of UGT1A1 and UGT1A9, enzymes for puerarin metabolism, were significantly increased in the liver and heart tissues of AAC rats and Ang II-treated NRCMs. Interestingly, the silencing of Nrf2 attenuated the puerarin-induced upregulation of UGT1A1 and UGT1A9. The results of chromatin immunoprecipitation-quantitative polymerase chain reaction indicated that the binding of Nrf2 to the promoter region of Ugt1a1 or Ugt1a9 was significantly enhanced in puerarin-treated cardiomyocytes. These results suggest that Nrf2 is the key regulator of antihypertrophic effects and upregulation of the metabolic enzymes UGT1A1 and UGT1A9 of puerarin. The autoregulatory circuits between puerarin and Nrf2-induced UGT1A1/1A9 are beneficial to attenuate adverse effects and maintain the pharmacologic effects of puerarin.


Assuntos
Cardiomegalia/metabolismo , Cardiomegalia/prevenção & controle , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Isoflavonas/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Animais , Cardiomegalia/genética , Cardiomegalia/patologia , Feminino , Glucuronosiltransferase/genética , Glucuronosiltransferase/metabolismo , Masculino , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Estresse Oxidativo/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Ratos , Ratos Sprague-Dawley , Regulação para Cima/efeitos dos fármacos
3.
Blood ; 128(24): 2797-2807, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27737889

RESUMO

Diffuse large B-cell lymphomas (DLBCLs) contain 2 major molecular subtypes; namely, the germinal center B-cell-like (GCB) and the activated B-cell-like (ABC) DLBCLs. It is well documented that ABC-DLBCL cases have a significantly poorer survival response than GCB-DLBCLs in both the CHOP (cyclophosphamide, vincristine, doxorubicin, and prednisone) and the rituximab (R)-CHOP eras. However, the underlying cause of this subtype disparity is poorly understood. Nevertheless, these clinical observations raise the possibility for an ABC-DLBCL-specific resistance mechanism that is directed toward 1 of the CHOP components and is inadequately addressed by rituximab. Here, we report that the main cytotoxic ingredient in CHOP, doxorubicin (Dox), has subtype-specific mechanisms of cytotoxicity in DLBCLs resulting from differences in the subcellular distribution pattern. Specifically, in cell line models of ABC-DLBCL, Dox is often enriched in the cytoplasm away from the nuclear DNA. As a result, Dox-induced cytotoxicity in ABC-DLBCLs is often dependent on oxidative stress, rather than DNA damage response. These findings are corroborated by gene signature analysis, which demonstrates that basal oxidative stress status predicts treatment outcome among patients with ABC-DLBCL, but not patients with GCB-DLBCL. In terms of redox-related resistance mechanism, our results suggest that STAT3 confers Dox resistance in ABC-DLBCLs by reinforcing an antioxidant program featuring upregulation of the SOD2 gene. Furthermore, a small-molecule STAT3 inhibitor synergizes with CHOP to trigger oxidative stress and kill ABC-DLBCL cells in preclinical models. These results provide a mechanistic basis for development of novel therapies that target either STAT3 or redox homeostasis to improve treatment outcomes for ABC-DLBCLs.


Assuntos
Linfócitos B/patologia , Doxorrubicina/uso terapêutico , Ativação Linfocitária/efeitos dos fármacos , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/patologia , Estresse Oxidativo/efeitos dos fármacos , Antioxidantes/metabolismo , Linfócitos B/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Compostos Clorados/farmacologia , Dano ao DNA , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Sinergismo Farmacológico , Centro Germinativo/efeitos dos fármacos , Centro Germinativo/patologia , Humanos , Compostos de Platina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição STAT3/metabolismo , Bibliotecas de Moléculas Pequenas/farmacologia , Resultado do Tratamento
4.
Metabolism ; 146: 155660, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37451670

RESUMO

BACKGROUND AND OBJECTIVES: MicroRNA-dependent regulation of hepatic lipid metabolism has been recognized recently as a key pathological mechanism contributing to the development of NAFLD. However, whether miR-32-5p (miR-32) plays a role in lipid metabolism or contributes to NAFLD remains unclear. METHODS AND RESULTS: A marked increase in miR-32 expression was observed in liver samples from patients and mice with NAFLD, as well as in palmitate-induced hepatocytes. Hepatocyte-specific miR-32 knockout (miR-32-HKO) dramatically ameliorated hepatic steatosis and metabolic disorders in high-fat diet-fed mice. Conversely, hepatic miR-32 overexpression markedly exacerbated the progression of these abnormalities. Further, combinational analysis of transcriptomics and lipidomics suggested that miR-32 was a key trigger for de novo lipogenesis in the liver. Mechanistically, RNA sequencing, luciferase assay and adenovirus-mediated downstream gene rescue assay demonstrated that miR-32 directly bound to insulin-induced gene 1 (INSIG1) and subsequently activated sterol regulatory element binding protein-mediated lipogenic gene programs, thereby promoting hepatic lipid accumulation and metabolic disorders. Notably, pharmacological administration of miR-32 antagonist significantly inhibited palmitate-induced triglyceride deposition in hepatocytes and markedly mitigated hepatic steatosis and metabolic abnormalities in obesity-associated NAFLD mice. CONCLUSION: miR-32 is an important checkpoint for lipogenesis in the liver, and targeting miR-32 could be a promising therapeutic approach for NAFLD treatment.


Assuntos
Hiperlipidemias , MicroRNAs , Hepatopatia Gordurosa não Alcoólica , Animais , Camundongos , Humanos , Lipogênese/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hiperlipidemias/metabolismo , Células Hep G2 , Fígado/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Dieta Hiperlipídica/efeitos adversos , Palmitatos , Camundongos Endogâmicos C57BL
5.
JMIR AI ; 2: e44537, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38875565

RESUMO

BACKGROUND: Ground-glass opacities (GGOs) appearing in computed tomography (CT) scans may indicate potential lung malignancy. Proper management of GGOs based on their features can prevent the development of lung cancer. Electronic health records are rich sources of information on GGO nodules and their granular features, but most of the valuable information is embedded in unstructured clinical notes. OBJECTIVE: We aimed to develop, test, and validate a deep learning-based natural language processing (NLP) tool that automatically extracts GGO features to inform the longitudinal trajectory of GGO status from large-scale radiology notes. METHODS: We developed a bidirectional long short-term memory with a conditional random field-based deep-learning NLP pipeline to extract GGO and granular features of GGO retrospectively from radiology notes of 13,216 lung cancer patients. We evaluated the pipeline with quality assessments and analyzed cohort characterization of the distribution of nodule features longitudinally to assess changes in size and solidity over time. RESULTS: Our NLP pipeline built on the GGO ontology we developed achieved between 95% and 100% precision, 89% and 100% recall, and 92% and 100% F1-scores on different GGO features. We deployed this GGO NLP model to extract and structure comprehensive characteristics of GGOs from 29,496 radiology notes of 4521 lung cancer patients. Longitudinal analysis revealed that size increased in 16.8% (240/1424) of patients, decreased in 14.6% (208/1424), and remained unchanged in 68.5% (976/1424) in their last note compared to the first note. Among 1127 patients who had longitudinal radiology notes of GGO status, 815 (72.3%) were reported to have stable status, and 259 (23%) had increased/progressed status in the subsequent notes. CONCLUSIONS: Our deep learning-based NLP pipeline can automatically extract granular GGO features at scale from electronic health records when this information is documented in radiology notes and help inform the natural history of GGO. This will open the way for a new paradigm in lung cancer prevention and early detection.

6.
Front Endocrinol (Lausanne) ; 13: 839849, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35273574

RESUMO

The prevalence of obesity is escalating and has become a worldwide health challenge coinciding with the development of metabolic diseases. Emerging evidence has shown that obesity is accompanied by the infiltration of macrophages into adipose tissue, contributing to a state of low-grade chronic inflammation and dysregulated metabolism. Moreover, in the state of obesity, the phenotype of adipose tissue macrophages switches from the M2 polarized state to the M1 state, thereby contributing to chronic inflammation. Notably, multiple metabolic organs (adipose tissue, gut, skeletal muscle, and the liver) communicate with adipose tissue macrophages via secreting organokines or exosomes. In this review, we systematically summarize how the organokines (adipokines, gut microbiota and its metabolites, gut cytokines, myokines, and hepatokines) and exosomes (adipocyte-, skeletal muscle-, and hepatocyte-derived exosomes) act as important triggers for macrophage recruitment in adipose tissue and adipose tissue macrophage polarization, thus providing further insight into obesity treatment. In addition, we also highlight the complex interaction of organokines with organokines and organokines with exosomes, revealing new paths in understanding adipose tissue macrophage recruitment and polarization.


Assuntos
Exossomos , Tecido Adiposo/metabolismo , Exossomos/metabolismo , Humanos , Inflamação/metabolismo , Macrófagos/metabolismo , Obesidade/metabolismo
7.
Biomed Pharmacother ; 125: 109825, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32036208

RESUMO

Vascular complications induced by diabetes constitute the principal cause of morbidity and mortality in diabetic patients. It has been reported that carvacrol (CAR) possesses a wide range of biological activities. The effects of CAR on diabetes-induced vasculopathy remain unknown. In this study, diabetic mice were created by the intraperitoneal injection of streptozotocin (STZ) in male C57BL/6 J mice to investigate whether CAR provided a protective effect against diabetes-induced vasculopathy and to investigate the underlying mechanisms. We found that CAR decreased blood glucose levels in diabetic mice. Moreover, CAR ameliorated diabetes-induced aortic morphological alterations, as evidenced by an increased thickness in the intima-media width and an increased number of vascular smooth muscle cells (VSMCs) layers. Further studies revealed that CAR inhibited hypercontractility in the aortas of diabetic mice and VSMCs in response to hyperglycemia, as evidenced by the relaxation of phenylephrine(PE)-induced vasoconstriction, the decreased expression of smooth muscle (SM)-α-actin, and the increased expression of Ki67 and proliferating cell nuclear antigen (PCNA). Furthermore, the PI3K/Akt signaling pathway was inhibited in the aortas of diabetic mice and VSMCs in response to hyperglycemia, while CAR treatment activated the PI3K/Akt signaling pathway. In conclusion, our results strongly suggest that CAR plays a protective role in diabetes-induced aortic hypercontractility, possibly by activating the PI3K/Akt signaling pathway. CAR is a potential drug for the treatment of diabetic vasculopathy.


Assuntos
Aorta/efeitos dos fármacos , Cimenos/farmacologia , Diabetes Mellitus Experimental/complicações , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Glicemia/efeitos dos fármacos , Proteínas Contráteis/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , Músculo Liso Vascular/efeitos dos fármacos , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
8.
Clin Cancer Res ; 25(12): 3589-3601, 2019 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-30862694

RESUMO

PURPOSE: To evaluate therapeutic activity of PAK inhibition in ATLL and to characterize the role of PAK isoforms in cell proliferation, survival, and adhesion of ATLL cells in preclinical models. EXPERIMENTAL DESIGN: Frequency and prognostic impact of PAK2 amplification were evaluated in an ATLL cohort of 370 cases. Novel long-term cultures and in vivo xenograft models were developed using primary ATLL cells from North American patients. Two PAK inhibitors were used to block PAK kinase activity pharmacologically. siRNA-based gene silencing approach was used to genetically knockdown (KD) PAK1 and PAK2 in ATLL cell lines. RESULTS: PAK1/2/4 are the three most abundantly expressed PAK family members in ATLL. PAK2 amplifications are seen in 24% of ATLLs and are associated with worse prognosis in a large patient cohort. The pan-PAK inhibitor PF-3758309 (PF) has strong in vitro and in vivo activity in a variety of ATLL preclinical models. These activities of PF are likely attributed to its ability to target several PAK isoforms simultaneously because genetic silencing of either PAK1 or PAK2 produced more modest effects. PAK2 plays a major role in CADM1-mediated stromal interaction, which is an important step in systemic dissemination of the disease. This finding is consistent with the observation that PAK2 amplification is more frequent in aggressive ATLLs and correlates with inferior outcome. CONCLUSIONS: PAK2, a gene frequently amplified in ATLL, facilitates CADM1-mediated stromal interaction and promotes survival of ATLL cells. Taken together, PAK inhibition may hold significant promise as a targeted therapy for aggressive ATLLs.


Assuntos
Leucemia-Linfoma de Células T do Adulto/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/farmacologia , Pirróis/farmacologia , Quinases Ativadas por p21/antagonistas & inibidores , Adulto , Animais , Adesão Celular/efeitos dos fármacos , Molécula 1 de Adesão Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Amplificação de Genes , Humanos , Leucemia-Linfoma de Células T do Adulto/genética , Leucemia-Linfoma de Células T do Adulto/metabolismo , Leucemia-Linfoma de Células T do Adulto/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Cultura Primária de Células , RNA Interferente Pequeno/genética , Taxa de Sobrevida , Ensaios Antitumorais Modelo de Xenoenxerto , Quinases Ativadas por p21/genética
9.
Acupunct Med ; 32(6): 495-502, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25341497

RESUMO

BACKGROUND: Spontaneous intracerebral haemorrhage (ICH) is the most devastating subtype of stroke, but there is currently no evidence-based treatment strategy. Acupuncture is a well-known traditional Chinese therapy for stroke-induced disability, and GV20 is the commonly used acupuncture point. OBJECTIVE: To evaluate the efficacy of GV20-based acupuncture in animal models of acute ICH. METHODS: Studies of GV20-based acupuncture in animal models of acute ICH were identified from six databases up to July 2013. Study quality for each included article was evaluated according to the CAMARADES 10-item checklist. Outcome measures were neurological deficit scores and brain water content. All the data were analysed using RevMan V.5.1 software. RESULTS: Nineteen studies were identified describing procedures involving 1628 animals. The quality score of the studies ranged from 3 to 6, with a mean of 4.6. The global estimate of the effect of GV20-based acupuncture was 0.19 (95% CI 0.13 to 0.25, p<0.001) SDs improvement in outcome compared with controls. In subgroup analyses, size of effect was higher where the outcome was measured as the neurological deficit score than the brain water content or both (p<0.001). CONCLUSIONS: These findings show the possible efficacy of GV20-based acupuncture in animal models of acute ICH, suggesting it as a candidate therapy for acute ICH.


Assuntos
Pontos de Acupuntura , Terapia por Acupuntura , Encéfalo/patologia , Hemorragia Cerebral/terapia , Couro Cabeludo , Acidente Vascular Cerebral/terapia , Animais , Hemorragia/terapia , Modelos Animais , Acidente Vascular Cerebral/metabolismo
10.
Cancer Cell ; 24(3): 282-4, 2013 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-24029225

RESUMO

Bach2 is a transcription factor required for affinity maturation of B cells. A recent study reveals, quite unexpectedly, that Bach2 also plays a key role in the pre-B cell receptor checkpoint and functions as a tumor suppressor in pre-B cell acute lymphocytic leukemia.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Receptores de Células Precursoras de Linfócitos B/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais
11.
ACS Chem Biol ; 7(6): 1015-22, 2012 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-22424086

RESUMO

Expressed protein ligation bridges the gap between synthetic peptides and recombinant proteins and thereby significantly increases the size and complexity of chemically synthesized proteins. Although the intein-based expressed protein ligation method has been extensively used in this regard, the development of new expressed protein ligation methods may improve the flexibility and power of protein semisynthesis. In this study a new alternative version of expressed protein ligation is developed by combining the recently developed technologies of hydrazide-based peptide ligation and genetic code expansion. Compared to the previous intein-based expressed protein ligation method, the new method does not require the use of protein splicing technology and generates recombinant protein α-hydrazides as ligation intermediates that are more chemically stable than protein α-thioesters. Furthermore, the use of an evolved mutant pyrrolysyl-tRNA synthetase(PylRS), ACPK-RS, from M. barkeri shows an improved performance for the expression of recombinant protein backbone oxoesters. By using HdeA as a model protein we demonstrate that the hydrazide-based method can be used to synthesize proteins with correctly folded structures and full biological activity. Because the PylRS-tRNACUAPyl system is compatible with both prokaryotic and eukaryotic cells,the strategy presented here may be readily expanded to manipulate proteins produced in mammalian cells. The new hydrazide-based method may also supplement the intein-based expressed protein ligation method by allowing for a more flexible selection of ligation site.


Assuntos
Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Hidrazinas/química , Hidroxiácidos/química , Engenharia de Proteínas/métodos , Escherichia coli/química , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Expressão Gênica , Hidrazinas/metabolismo , Hidroxiácidos/metabolismo , Modelos Moleculares , Dobramento de Proteína , Estabilidade Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
12.
PLoS One ; 5(12): e15881, 2010 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-21209918

RESUMO

Murine leukemia virus (MLV)-based retroviral vector is widely used for gene transfer. Efficient packaging of the genomic RNA is critical for production of high-titer virus. Here, we report that expression of the insulin-like growth factor II mRNA binding protein 1 (IMP1) enhanced the production of infectious MLV vector. Overexpression of IMP1 increased the stability of viral genomic RNA in virus producer cells and packaging of the RNA into progeny virus in a dose-dependent manner. Downregulation of IMP1 in virus producer cells resulted in reduced production of the retroviral vector. These results indicate that IMP1 plays a role in regulating the packaging of MLV genomic RNA and can be used for improving production of retroviral vectors.


Assuntos
Regulação Viral da Expressão Gênica , Vírus da Leucemia Murina/metabolismo , Proteínas de Ligação a RNA/metabolismo , Animais , Produtos Biológicos/genética , Linhagem Celular , Vetores Genéticos , Genoma Viral , Humanos , Camundongos , Células NIH 3T3 , RNA Viral/genética , Ratos , Retroviridae/genética , Montagem de Vírus/genética
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