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1.
Gut ; 69(2): 231-242, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31068366

RESUMO

OBJECTIVE: Gastric cancer (GC) is a leading cause of cancer mortality. Previous studies have shown that hepatocyte nuclear factor-4α (HNF4α) is specifically overexpressed in GC and functionally required for GC development. In this study, we investigated, on a genome-wide scale, target genes of HNF4α and oncogenic pathways driven by HNF4α and HNF4α target genes. DESIGN: We performed HNF4α chromatin immunoprecipitation followed by sequencing across multiple GC cell lines, integrating HNF4α occupancy data with (epi)genomic and transcriptome data of primary GCs to define HNF4α target genes of in vitro and in vivo relevance. To investigate mechanistic roles of HNF4α and HNF4α targets, we performed cancer metabolic measurements, drug treatments and functional assays including murine xenograft experiments. RESULTS: Gene expression analysis across 19 tumour types revealed HNF4α to be specifically upregulated in GCs. Unbiased pathway analysis revealed organic acid metabolism as the top HNF4α-regulated pathway, orthogonally supported by metabolomic analysis. Isocitrate dehydrogenase 1 (IDH1) emerged as a convergent HNF4α direct target gene regulating GC metabolism. We show that wild-type IDH1 is essential for GC cell survival, and that certain GC cells can be targeted by IDH1 inhibitors. CONCLUSIONS: Our results highlight a role for HNF4α in sustaining GC oncogenic metabolism, through the regulation of IDH1. Drugs targeting wild-type IDH1 may thus have clinical utility in GCs exhibiting HNF4α overexpression, expanding the role of IDH1 in cancer beyond IDH1/2 mutated malignancies.


Assuntos
Fator 4 Nuclear de Hepatócito/genética , Isocitrato Desidrogenase/metabolismo , Neoplasias Gástricas/genética , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Feminino , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Marcação de Genes/métodos , Fator 4 Nuclear de Hepatócito/metabolismo , Humanos , Isocitrato Desidrogenase/antagonistas & inibidores , Camundongos Endogâmicos NOD , Terapia de Alvo Molecular/métodos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Regiões Promotoras Genéticas/genética , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Regulação para Cima/genética , Ensaios Antitumorais Modelo de Xenoenxerto
2.
Medicine (Baltimore) ; 98(50): e18194, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31852075

RESUMO

OBJECTIVE: To date, there are several published studies on the value of IDH-1 (isocitrate dehydrogenase-1) mutation and MGMT (O6-Methylguanine-DNA methyltransferas) promoter methylated status on the diagnosis of pseudoprogression (PSP) and true tumor progression after or within chemo-radiotherapy of high grade glioma (HGG). We performed a meta-analysis about the significant value of these 2 molecular markers on the diagnosis of PsP in high- grade glioma. METHODS: We searched the eligible studies from PubMed, Medline, Embase, Chinese Biomedical Literature Database (CBM), China National Knowledge Infrastructure (CNKI) and Wan Fang Database. The relevant studies published before October 2018 were identified. ORs (odds ratios) with 95%CIs (confidence intervals) were used to evaluate the value using fixed- or random-effect model. RESULTS: Thirteen studies about MGMT promoter methylated status and 4 studies about IDH-1 mutations were found eligible for this present meta-analysis. Significant value of MGMT promoter methylation status (OR = 4.02, 95%CI = 2.76-5.87, P < .001) and IDH-1 mutations (OR = 12.78, 95%CI = 3.86-42.35, P < .001) were observed. CONCLUSIONS: This meta-analysis provided evidences that MGMT promoter methylation status and IDH-1 mutations could distinguish PSP from true tumor progression.


Assuntos
Neoplasias Encefálicas/genética , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , DNA de Neoplasias/genética , Glioma/genética , Isocitrato Desidrogenase/genética , Mutação , Estadiamento de Neoplasias , Proteínas Supressoras de Tumor/genética , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/metabolismo , Metilação de DNA , Metilases de Modificação do DNA/metabolismo , Enzimas Reparadoras do DNA/metabolismo , DNA de Neoplasias/metabolismo , Progressão da Doença , Glioma/diagnóstico , Glioma/metabolismo , Humanos , Isocitrato Desidrogenase/metabolismo , Regiões Promotoras Genéticas , Proteínas Supressoras de Tumor/metabolismo
3.
Eur J Med Chem ; 183: 111694, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31561044

RESUMO

Isocitrate dehydrogenase 1 (IDH1), which catalyzes the conversion of isocitrate to α-ketoglutarate, is one of key enzymes in the tricarboxylic acid cycle (TCA). Hotspot mutation at Arg132 in IDH1 that alters the function of IDH1 by further converting the α-ketoglutarate(α-KG) to 2-hydroxyglutarate (2-HG) have been identified in a variety of cancers. Because the IDH1 mutations occur in a significant portion of gliomas and glioblastomas, it is important that IDH1 inhibitors have to be brain penetrant to treat IDH1-mutant brain tumors. Here we report the efforts to design and synthesize a novel serial of mutant IDH1 inhibitors with improved activity and the blood-brain barrier (BBB) penetration. We show that compound 5 exhibits good brain exposure and potent 2-HG inhibition in a HT1080-derived mouse xenograft model, which makes it a potential preclinical candidate to treat IDH1-mutant brain tumors.


Assuntos
Antineoplásicos/farmacologia , Barreira Hematoencefálica/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Descoberta de Drogas , Glioma/tratamento farmacológico , Isocitrato Desidrogenase/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Glioma/metabolismo , Glioma/patologia , Humanos , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas
4.
Expert Opin Pharmacother ; 20(16): 1935-1942, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31454277

RESUMO

Introduction: Despite recent progress, the prognosis of acute myeloid leukemia remains poor, mainly in older and in relapsed/refractory patients. Recently, a large number of novel agents have been developed thanks to a better understanding of its pathogenesis. Among these, the potent inhibitor of the isocitrate dehydrogenase-2 (IDH2) mutant protein, enasidenib (formerly AG-221), has demonstrated promising antileukemic activity by targeting IDH2 mutations. Area covered: This review describes the mechanisms of action, the pharmacodynamic and pharmacokinetic properties, the safety, and efficacy of enasidenib. Phase I/II/III clinical trials are also reported and discussed. Expert opinion: Enasidenib is a novel agent able to differentiate leukemic blasts in functional, maturating cells. This drug is characterized by oral bioavailability and good tolerability. As a monotherapy, it demonstrates clinical and laboratorial improvement, in 19.6% and 38.8% of cases respectively. Differentiation syndrome is the most relevant, potentially life-threatening side effect, which physicians must be aware of. The authors believe that the way forwards now is to explore the role of enasidenib as a chemoresistance revertant when associated with chemotherapy, as a 'bridge to transplant' or when associated other novel agents if we wish to maximize its use.


Assuntos
Aminopiridinas/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Triazinas/uso terapêutico , Aminopiridinas/efeitos adversos , Aminopiridinas/farmacocinética , Ensaios Clínicos como Assunto , Aprovação de Drogas , Inibidores Enzimáticos/efeitos adversos , Inibidores Enzimáticos/farmacocinética , Inibidores Enzimáticos/uso terapêutico , Meia-Vida , Humanos , Isocitrato Desidrogenase/antagonistas & inibidores , Isocitrato Desidrogenase/metabolismo , Prognóstico , Resultado do Tratamento , Triazinas/efeitos adversos , Triazinas/farmacocinética
5.
Clin Nucl Med ; 44(10): e548-e558, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31306196

RESUMO

AIM: To study the association of metabolic features of F-fluorocholine in gliomas with histopathological and molecular parameters, progression-free survival (PFS) and overall survival (OS). METHODS: Prospective multicenter and nonrandomized study (Functional and Metabolic Glioma Analysis). Patients underwent a basal F-fluorocholine PET/CT and were included after histological confirmation of glioma. Histological and molecular profile was assessed: grade, Ki-67, isocitrate dehydrogenase status and 1p/19q codeletion. Patients underwent standard treatment after surgery or biopsy, depending on their clinical situation. Overall survival and PFS were obtained after follow-up. After tumor segmentation of PET images, SUV and volume-based variables, sphericity, surface, coefficient of variation, and multilesionality were obtained. Relations of metabolic variables with histological, molecular profile and prognosis were evaluated using Pearson χ and t test. Receiver operator caracteristic curves were used to obtain the cutoff of PET variables. Survival analysis was performed using Kaplan-Meier and Cox regression analysis. RESULTS: Forty-five patients were assessed; 38 were diagnosed as having high-grade gliomas. Significant differences of SUV-based variables with isocitrate dehydrogenase status, tumor grade, and Ki-67 were found. Tumor grade, Ki-67, SUVmax, and SUVmean were related to progression. Kaplan-Meier analysis revealed significant associations of SUVmax, SUVmean, and multilesionaly with OS and PFS. SUVmean, sphericity, and multilesionality were independent predictors of OS and PFS in Cox regression analysis. CONCLUSIONS: Metabolic information obtained from F-fluorocholine PET of patients with glioma may be useful in the prediction of tumor biology and patient prognosis.


Assuntos
Colina/análogos & derivados , Glioma/diagnóstico por imagem , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons , Deleção Cromossômica , Progressão da Doença , Feminino , Glioma/genética , Glioma/metabolismo , Glioma/patologia , Humanos , Isocitrato Desidrogenase/metabolismo , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Intervalo Livre de Progressão , Estudos Prospectivos
6.
Clin Nucl Med ; 44(10): e581-e582, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31348085

RESUMO

A variety of neoplastic and nonneoplastic conditions involve the corpus callosum, which may result in a "butterfly" appearance on conventional MRI. Typically, that pattern shows a bilateral and heterogeneous contrast enhancement of the lesion, occasionally with central nonenhancing areas indicating intralesional necrosis. In contrast, anaplastic gliomas may show only minimal or even a lack of contrast enhancement on MRI. We here report neuroimaging findings in a 69-year-old man with a "butterfly" pattern on dynamic FET [O-(2-[F]-fluoroethyl)-L-tyrosine] PET and the diagnosis of an anaplastic astrocytoma (WHO grade III; IDH-1/-2 wildtype, no 1p/19q co-deletion) but without typical MRI contrast enhancement.


Assuntos
Astrocitoma/diagnóstico por imagem , Astrocitoma/enzimologia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/enzimologia , Isocitrato Desidrogenase/metabolismo , Tomografia por Emissão de Pósitrons , Tirosina/análogos & derivados , Idoso , Astrocitoma/genética , Astrocitoma/patologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Humanos , Isocitrato Desidrogenase/genética , Imagem por Ressonância Magnética , Masculino
7.
Cancer Sci ; 110(10): 3306-3314, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31361380

RESUMO

Isocitrate dehydrogenase 2 (IDH2), an important mitochondrial metabolic enzyme involved in the tricarboxylic acid cycle, is mutated in a variety of cancers. AG-221, an inhibitor primarily targeting the IDH2-R140Q mutant, has shown remarkable clinical benefits in the treatment of relapsed or refractory acute myeloid leukemia patients. However, AG-221 has weak inhibitory activity toward IDH2-R172K, a mutant form of IDH2 with more severe clinical manifestations. Herein, we report TQ05310 as the first mutant IDH2 inhibitor that potently targets both IDH2-R140Q and IDH2-R172K mutants. TQ05310 inhibited mutant IDH2 enzymatic activity, suppressed (R)-2-hydroxyglutarate (2-HG) production and induced differentiation in cells expressing IDH2-R140Q and IDH2-R172K, but not in cells expressing wild-type IDH1/2 or mutant IDH1. TQ05310 bound to both IDH2-R140Q and IDH2-R172K, with Q316 being the critical residue mediating the binding of TQ05310 with IDH2-R140Q, but not with IDH2-R172K. TQ05310 also had favorable pharmacokinetic characteristics and profoundly inhibited 2-HG production in a tumor xenografts model. The results of the current study establish a solid foundation for further clinical investigation of TQ05310, and provide new insight into the development of novel mutant IDH2 inhibitors.


Assuntos
Substituição de Aminoácidos , Inibidores Enzimáticos/administração & dosagem , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Neoplasias/tratamento farmacológico , Animais , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacocinética , Inibidores Enzimáticos/farmacologia , Feminino , Células HEK293 , Humanos , Isocitrato Desidrogenase/antagonistas & inibidores , Isocitrato Desidrogenase/química , Camundongos , Modelos Moleculares , Simulação de Acoplamento Molecular , Neoplasias/genética , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Virchows Arch ; 475(5): 625-636, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31240473

RESUMO

Mosaic somatic mutations in the isocitrate dehydrogenase 1/2 (IDH1/2) genes have been identified in most enchondromas by targeted mutation analysis. Next-generation sequencing (NGS), that may detect even low-level mosaic mutation rates, has not previously been applied to enchondromas. Immunohistochemistry using the H09 clone is routinely used as a surrogate for the common R132H IDH1 mutation in gliomas. We compared immunohistochemistry and NGS results in a series of 13 enchondromas from 8 pediatric patients. NGS identified a heterozygous IDH mutation in all enchondromas, showing identical mutation status in patients with multiple tumors assessed, thereby confirming somatic mosaicism. A majority of the tumors harbored an IDH1 mutation (p.R132H in 3 tumors; p.R132C in 4 tumors from 2 patients; p.R132L and p.R132G in one tumor each). A p.R172S IDH2 mutation was identified in 4 enchondromas, but not in the ependymoma from one patient with Ollier disease, who further displayed a heterozygous STK11 missense mutation. IDH mutation rates varied between 14% (indicative of mutations in 28% of the cells and of intratumoral mosaicism) and 45% (tumor content was close to 100%). Cytoplasmic H09 reactivity was observed as expected in tumors with an IDH1 p.R132H mutation; cross-reactivity was seen with the p.R132L variant. This first NGS study of pediatric enchondromas confirms that IDH mutations may occur in a mosaic fashion. STK11 gene mutations may provide insights in the development of multiple cartilaginous tumors in enchondromatosis, this tumor suppressor gene having been shown in animal models to regulate both chondrocyte maturation and growth plate organization during development.


Assuntos
Condroma/genética , Encondromatose/genética , Isocitrato Desidrogenase/genética , Proteínas Serina-Treonina Quinases/genética , Adolescente , Criança , Pré-Escolar , Condroma/metabolismo , Condroma/patologia , Encondromatose/metabolismo , Encondromatose/patologia , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imuno-Histoquímica , Isocitrato Desidrogenase/metabolismo , Masculino , Mutação , Análise de Sequência de DNA
9.
Drugs ; 79(11): 1177-1186, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31222627

RESUMO

Acute myeloid leukemia (AML) is a heterogeneous disease characterized by clonal expansion of myeloid progenitor cells, resulting in disturbed hematopoiesis and bone marrow failure. For decades, AML therapy was relatively straightforward: clinicians assessed whether the patient was fit or unfit for standard chemotherapy and selected the treatment from among limited choices. With the advent of high-throughput sequencing technologies, significant progress has been made in unraveling the AML genome and understanding leukemogenesis driven by recurrent mutations in signaling and kinase pathways, DNA methylation, and spliceosome complex genes. We are now poised to see our research-based advances translate clinically into the treatment of patients with AML. As recently as within the last 2 years, the United States Food and Drug Administration (FDA) approved eight novel therapies for patients with AML. In this review, we discuss recently approved agents targeting fms-like tyrosine kinase 3 (FLT3), isocitrate dehydrogenase (IDH), B-cell lymphoma-2 (BCL-2), and other promising novel AML agents that are in late stages of clinical development.


Assuntos
Antineoplásicos/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Ensaios Clínicos como Assunto , Metilação de DNA , Humanos , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Terapia de Alvo Molecular/métodos , Mutação , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Análise de Sequência de DNA , Estados Unidos , United States Food and Drug Administration , Tirosina Quinase 3 Semelhante a fms/genética , Tirosina Quinase 3 Semelhante a fms/metabolismo
10.
Semin Thromb Hemost ; 45(4): 334-341, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31041803

RESUMO

Venous thromboembolism (VTE) is a common complication in patients with primary brain tumors, with up to 20% of patients per year having a VTE event. Clinical risk factors for VTE include glioblastoma subtype, paresis, or surgery. Furthermore, specific factors playing a role in tumor biology were recently identified to predispose to prothrombotic risk. For instance, mutations in the isocitrate dehydrogenase 1 (IDH1) gene, which occurs in a subgroup of glioma, correlate with risk of VTE, with low incidence in patients with presence of an IDH1 mutation compared with those with IDH1 wild-type status. In addition, expression of the glycoprotein podoplanin on brain tumors was associated with both intratumoral thrombi and high risk of VTE. As podoplanin has the ability to activate platelets, a mechanistic role of podoplanin-mediated platelet activation in VTE development has been suggested. From a clinical point of view, the management of patients with primary brain tumors and VTE is challenging. Anticoagulation is required to treat patients; however, it is associated with increased risk of intracranial hemorrhage. This review focuses on describing the epidemiology, risk factors, and mechanisms of brain tumor-associated thrombosis and discusses clinical challenges in the prevention and treatment of VTE in patients with brain tumors.


Assuntos
Anticoagulantes/uso terapêutico , Neoplasias Encefálicas/complicações , Glioblastoma/complicações , Trombose/tratamento farmacológico , Tromboembolia Venosa/tratamento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Mutação , Ativação Plaquetária , Trombose/diagnóstico , Trombose/etiologia , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/etiologia
11.
Technol Cancer Res Treat ; 18: 1533033819828396, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30943868

RESUMO

To date, diagnosis of IDH1 mutation is based on DNA sequencing and immunohistochemistry, methods limited in terms of sensitivity and ease of use. Recently, the diagnosis of IDH1 mutation by real-time polymerase chain reaction was introduced as an alternative method. In this study, real-time polymerase chain reaction was validated as a tool for detection of IDH1 mutation, and expression levels were analyzed for correlation with course of the disease. A total of 113 tumor samples were obtained intraoperatively from 84 patients with glioma having a diagnosis of diffuse glioma (World Health Organization II), anaplastic glioma (World Health Organization III), secondary glioblastoma ± chemotherapy, primary glioblastoma ± chemotherapy (World Health Organization IV). Tumor samples were snap frozen and processed for sectioning and RNA and protein isolation. Presence of IDH1 mutation was determined by DNA sequencing. Hereafter, quantitative expression of IDH1 messenger RNA was assessed using real-time polymerase chain reaction with specific primers for IDH1 mutation and -wt; protein expression was verified by Western Blot analysis and immunohistochemistry. Additionally, 19 samples of low-grade glioma and their consecutive high-grade glioma were analyzed at different time points of the disease. IDH1 mutation was identified in 63% of samples by DNA sequencing. In correlation with the real-time polymerase chain reaction results, a cutoff value was determined. Above this threshold, sensitivity and specificity of real-time polymerase chain reaction in detecting IDH1 mutation were 98% and 94%, respectively. Quantitative analysis revealed that IDH1 mutation expression is upregulated in secondary glioblastoma (mean ± standard error of mean: 3.52 ± 0.55) compared to lower grade glioma (II = 1.54 ± 0.22; III = 1.67 ± 0.23). In contrast, IDH1 wt expression is upregulated in all glioma grades (concentration >0.1) compared to control brain tissue (0.007 ± 0.0016). Western Blot analysis showed a high concordance to both sequencing and real-time polymerase chain reaction results in qualitative analysis of IDH1 mutation status (specificity 100% and sensitivity 100%). Moreover, semiquantitative protein expression analysis also showed higher expression levels of mutated IDH1 in secondary glioblastoma. In our study, real-time polymerase chain reaction and Western Blot analysis were found to be highly efficient methods in detecting IDH1 mutation in glioma samples. As cost-effective and time-saving methods, real-time polymerase chain reaction and Western Blot analysis may therefore play an important role in IDH1 mutation analysis in the future. IDH1 mutation expression level was found to correlate with the course of disease to a certain extent. Yet, clinical factors as recurrent disease or prior radiochemotherapy did not alter IDH1 mutation expression level.


Assuntos
Western Blotting/métodos , Neoplasias Encefálicas/genética , Glioma/genética , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Mutação , Reação em Cadeia da Polimerase em Tempo Real/métodos , Adulto , Alelos , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Feminino , Glioma/metabolismo , Glioma/patologia , Humanos , Masculino , Pessoa de Meia-Idade
12.
Microb Cell Fact ; 18(1): 65, 2019 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-30943966

RESUMO

BACKGROUND: NAD(H/+) and NADP(H/+) are the most important redox cofactors in bacteria. However, the intracellular redox balance is in advantage of the cell growth and production of NAD(P)H-dependent products. RESULTS: In this paper, we rationally engineered glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and isocitrate dehydrogenase (IDH) to switch the nucleotide-cofactor specificity resulting in an increase in final titer [from 85.6 to 121.4 g L-1] and carbon yield [from 0.33 to 0.46 g (g glucose)-1] of L-lysine in strain RGI in fed-batch fermentation. To do this, we firstly analyzed the production performance of original strain JL-6, indicating that the imbalance of intracellular redox was the limiting factor for L-lysine production. Subsequently, we modified the native GAPDH and indicated that recombinant strain RG with nonnative NADP-GAPDH dramatically changed the intracellular levels of NADH and NADPH. However, L-lysine production did not significantly increase because cell growth was harmed at low NADH level. Lastly, the nonnative NAD-IDH was introduced in strain RG to increase the NADH availability and to equilibrate the intracellular redox. The resulted strain RGI showed the stable ratio of NADPH/NADH at about 1.00, which in turn improved cell growth (µmax. = 0.31 h-1) and L-lysine productivity (qLys, max. = 0.53 g g-1 h-1) as compared with strain RG (µmax. = 0.14 h-1 and qLys, max. = 0.42 g g-1 h-1). CONCLUSIONS: This is the first report of balancing the intracellular redox state by switching the nucleotide-cofactor specificity of GAPDH and IDH, thereby improving cell growth and L-lysine production.


Assuntos
Coenzimas/metabolismo , Corynebacterium glutamicum/crescimento & desenvolvimento , Corynebacterium glutamicum/metabolismo , Lisina/biossíntese , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Corynebacterium glutamicum/química , Corynebacterium glutamicum/genética , Fermentação , Glucose/metabolismo , Gliceraldeído-3-Fosfato Desidrogenases/genética , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Cinética , Engenharia Metabólica , NAD/metabolismo , NADP/metabolismo , Oxirredução
13.
World Neurosurg ; 128: e195-e208, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31003026

RESUMO

OBJECTIVE: We aimed to evaluate the usefulness of dynamic contrast-enhanced T1-weighted perfusion magnetic resonance imaging (DCE-pMRI) to predict certain immunohistochemical (IHC) biomarkers of glioblastoma (GB) in this pilot study. METHODS: We retrospectively reviewed 36 patients (male/female, 25:11; mean age, 53 years; age range, 29-85 years) who had pretreatment DCE-pMRI with IHC analysis of their excised GBs. Regions of interest of the enhancing tumor (ER) and nonenhancing peritumoral region (NER) were used to calculate DCE-pMRI parameters of volume transfer constant, back flux constant, volume of the extravascular extracellular space, initial area under enhancement curve, and maximum slope. IHC biomarkers including Ki-67 labeling index, epidermal growth factor receptor (EGFR), oligodendrocyte transcription factor 2 (OLIG2), isocitrate dehydrogenase 1 (IDH1), and p53 mutation status were determined. The imaging metrics of GB with IHC markers were compared using the Kruskal-Wallis test and Spearman correlation analysis. RESULTS: Among 30 patients with available IDH1 status, 14 patients (46.6%) had IDH1 mutation. EGFR amplification was present in 24/36 (66.6%) patients. Mean Ki-67 labeling index was 29% (range, 1.5%-80%). p53 mutation was present in 20/36 GBs (55%), whereas OLIG2 expression was positive in 29/36 GBs (80.5%). Various DCE-pMRI parameters gathered from the ER and NER were significantly correlated with IDH1 mutation, EGFR amplification, and OLIG2 expression (P < 0.05). Ki-67 labeling index showed a strong positive correlation with initial area under enhancement curve (r = 0.619; P < 0.001). CONCLUSIONS: DCE-pMRI could determine surrogate IHC biomarkers in GB via tumoral and peritumoral approach, potential targets for individualized treatment protocols.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Glioblastoma/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/cirurgia , Meios de Contraste , Receptores ErbB/metabolismo , Feminino , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/cirurgia , Humanos , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Antígeno Ki-67/metabolismo , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Fator de Transcrição 2 de Oligodendrócitos/metabolismo , Projetos Piloto , Estudos Retrospectivos , Proteína Supressora de Tumor p53/genética
14.
Pathologe ; 40(Suppl 1): 9-17, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31025086

RESUMO

BACKGROUND: Diffuse astrocytic and oligodendroglial gliomas are the most common neuroepithelial tumors. Their classification is based on the integration of histological and molecular findings according to the classification of tumors of the central nervous system published by the World Health Organization (WHO) in 2016. OBJECTIVES: This review describes the different entities and variants of diffuse gliomas and summarizes the current diagnostic criteria for these tumors. MATERIALS AND METHODS: Based on the 2016 WHO classification and selected other publications, the histomolecular diagnostics of diffuse gliomas is presented and illustrated. RESULTS: Diffuse gliomas are divided into isocitrate dehydrogenase (IDH)-mutant or IDH-wildtype gliomas by detection of mutations in the IDH1 or IDH2 genes. Among the IDH-mutant gliomas, oligodendroglial tumors are characterized by combined losses of chromosome arms 1p and 19q. Loss of nuclear expression of the ATRX protein is a marker of IDH- mutant astrocytic gliomas. Glioblastoma, IDH-wildtype, is the most common diffuse glioma. Diffuse and anaplastic astrocytic gliomas without IDH mutation should be further evaluated for molecular features of glioblastoma, IDH-wildtype. Diffuse gliomas in the thalamus, brainstem, or spinal cord carrying a histone 3 (H3)-K27M mutation are classified as diffuse midline gliomas, H3-K27M-mutant. By determining the IDH and 1p/19q status, oligoastrocytomas can be stratified into either astrocytic or oligodendroglial gliomas. Gliomatosis cerebri is no longer regarded as a distinct glioma entity. CONCLUSIONS: Diffuse gliomas can today be classified accurately and reproducibly by means of histological, immunohistochemical, and molecular analyses.


Assuntos
Astrócitos/patologia , Neoplasias Encefálicas/diagnóstico , Glioma/diagnóstico , Oligodendroglioma/patologia , Neoplasias Encefálicas/enzimologia , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Glioma/enzimologia , Glioma/genética , Glioma/patologia , Humanos , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Mutação , Proteína Nuclear Ligada ao X/metabolismo
15.
Int J Mol Sci ; 20(8)2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-31018543

RESUMO

The therapeutic approach for acute myeloid leukemia (AML) remains challenging, since over the last four decades a stagnation in standard cytotoxic treatment has been observed. But within recent years, remarkable advances in the understanding of the molecular heterogeneity and complexity of this disease have led to the identification of novel therapeutic targets. In the last two years, seven new targeted agents (midostaurin, gilteritinib, enasidenib, ivosidenib, glasdegib, venetoclax and gemtuzumab ozogamicin) have received US Food and Drug Administration (FDA) approval for the treatment of AML. These drugs did not just prove to have a clinical benefit as single agents but have especially improved AML patient outcomes if they are combined with conventional therapy. In this review, we will focus on currently approved and promising upcoming agents and we will discuss controversial aspects and limitations of targeted treatment strategies.


Assuntos
Antineoplásicos/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Imunoconjugados/uso terapêutico , Leucemia Mieloide Aguda/tratamento farmacológico , Terapia de Alvo Molecular/métodos , Animais , Aprovação de Drogas , Desenvolvimento de Medicamentos , Proteínas Hedgehog/antagonistas & inibidores , Proteínas Hedgehog/metabolismo , Humanos , Isocitrato Desidrogenase/antagonistas & inibidores , Isocitrato Desidrogenase/metabolismo , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Modelos Moleculares , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores , Tirosina Quinase 3 Semelhante a fms/metabolismo
16.
J Biol Regul Homeost Agents ; 33(2): 345-353, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30972998

RESUMO

5-methyl cytosine (5mC) can be oxidized to 5-hydroxymethyl cytosine (5hmC) under the action of TET protein family, and 5hmC plays important roles in the pathogenesis of various tumors including acute myeloid leukemia (AML). In this study, we evaluated the role of 5mC and 5hmC levels in HL60 AML cells and bone marrow samples from AML patients for KIT gene expression to analyze 5hmC level in AML pathogenesis. Results showed that the expression and 5hmC level increased significantly of the KIT gene but the change of its 5mC level was not obvious after being treated by decitabine (DAC) in HL60 cells. IDH1 and IDH2 expression increased followed by increased KIT 5hmC level. In AML patients with IDH1 or IDH2 mutation, KIT expression and 5hmC were much lower than in those without mutation. The study indicated that the expression of KIT gene was regulated by 5hmC level in HL60 cells, and the 5hmC level was regulated by IDH1 and IDH2.


Assuntos
5-Metilcitosina/análogos & derivados , Metilação de DNA , Leucemia Mieloide Aguda/genética , Proteínas Proto-Oncogênicas c-kit/genética , 5-Metilcitosina/química , Regulação Leucêmica da Expressão Gênica , Células HL-60 , Humanos , Isocitrato Desidrogenase/metabolismo , Mutação
17.
Neuropathology ; 39(2): 78-84, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30937985

RESUMO

Adult thalamic glioblastomas (GBM) are uncommon tumors with limited available molecular data. One of the reported molecular alterations in these tumors is the H3K27M mutation. It has been documented that H3K27M mutation is found in a high proportion of pediatric thalamic gliomas. In this study, we have analyzed the molecular alterations exclusive to adult thalamic GBM. This is a 6 years retrospective study of adult thalamic GBM patients who underwent surgical decompression of the tumor. Clinical data were obtained from the case records. Immunohistochemistry (IHC) was performed on the tumors using antibodies directed against the gene products of R132H mutant isocitrate dehydrogenase 1 (IDH1), alpha-thalassemia/mental retardation X-linked (ATRX), p53, H3K27M, H3K27me3, and V600E mutant BRAF. Molecular analyses were carried out to detect other IDH1 and IDH2 mutations, O6 -methylguanine-DNA-methyltransferase gene (MGMT) promoter methylation, and epidermal growth factor gene (EGFR) and telomerase reverse transcriptase gene (TERT) promoter mutations. A total of 42 cases of adult thalamic GBM were studied. The mean age of presentation was 42 years with age range of 19-58 years. Male predominance was noted. All the tumors were IDH wild-type, BRAF (V600E)-immunonegative and unmethylated for MGMT promoter. H3K27M immunopositivity was noted in 60% of tumors. Of these 33.3% were from older adults above the age of 50 years. Of the H3K27M-immunopositive cases, ATRX loss of expression was seen in 32%, p53 immunopositivity in 24% and EGFR amplification in 12%. Higher frequency of TERT promoter mutations was noted in H3K27M-immunonegative cases (58.8%) compared to immunopositive cases (20%). Ours is one of the few studies elucidating the molecular alterations exclusive to adult thalamic GBM. We show a high frequency of H3K27M immunopositivity, suggestive of its mutational status in these tumors, including in older adults.


Assuntos
Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Histonas/metabolismo , Tálamo/metabolismo , Adulto , Metilases de Modificação do DNA/metabolismo , Enzimas Reparadoras do DNA/metabolismo , Receptores ErbB/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Isocitrato Desidrogenase/metabolismo , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Telomerase/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Proteína Nuclear Ligada ao X/metabolismo , Adulto Jovem
18.
Free Radic Res ; 53(4): 418-429, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31020875

RESUMO

Melanoma is the most aggressive skin cancer due to a high propensity for metastasis, with a 10-year survival rate of less than 10%. The devastating clinical outcome and lack of effective preventative therapeutics for metastatic melanoma necessitate the development of new therapeutic strategies targeted to inhibit the regulatory circuits underlying the progression and metastasis of melanoma. Melanoma metastasis requires migration and invasion of the malignant tumour cells driven by proteolytic remodelling of the extracellular matrix (ECM) executed by matrix metalloproteinases (MMPs), particularly MMP-2 and MMP-9. Inhibiting components of these circuits defines new therapeutic opportunities for melanoma with metastatic malignancy. Oxalomalate (OMA) is a competitive inhibitor of NADP+-dependent isocitrate dehydrogenase (IDH), which plays an important role in cellular signalling pathways regulated by reactive oxygen species (ROS). In this study, we investigated the therapeutic role of OMA in metastatic melanoma and the associated underlying mechanism of action. We report that OMA-mediated inhibition of IDH enzymes suppresses metastatic melanoma through inhibition of invasive cell migration based on MMP-9-mediated proteolytic remodelling of the ECM. In particular, our study provides the mechanistic foundation that OMA reduces the expression and secretion of MMP-9 through LKB1-mediated PEA3 degradation via the ROS-dependent ATM-Chk2-p53 signalling axis, resulting from inhibition of IDH enzymes. These results provide evidence that OMA targeting of the stress response to ROS by IDH inhibition is a promising therapy for the treatment of metastatic melanoma.


Assuntos
Isocitrato Desidrogenase/metabolismo , Neoplasias Pulmonares/prevenção & controle , Melanoma Experimental/prevenção & controle , Oxalatos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Animais , Movimento Celular , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundário , Masculino , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos BALB C , Transdução de Sinais
19.
World Neurosurg ; 128: e21-e30, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30880199

RESUMO

OBJECTIVE: To explore related factors that influence time to recurrence and prognosis of gliomas. METHODS: A retrospective analysis of pathologic and clinical data of patients with glioma who underwent surgery for the first time and had a recurrence between 2009 and 2018 in West China Hospital was performed. Clinical characteristics of patients were reviewed, and survival analysis was performed to identify prognostic factors for the recurrent time. Molecules with differential changes in the paired samples were included in the survival analysis. RESULTS: A total of 84 patients met our inclusion requirements and were included in the study; other related factors were also considered in detail in the integrated analysis. Significant differences among O6-methylguanine-DNA methyltransferase (positive/negative), isocitrate dehydrogenase 1 (positive/negative), and Ki-67 were determined by statistical analysis of paired samples (P = 0.013, P = 0.014, P = 0.017). Univariate analysis demonstrated that Ki-67 (low expression, medium expression, high expression), initial World Health Organization grade (low or high), tumor side (left, right, middle), age (≥50 years, <50 years), and extent of resection were significantly correlated with time to recurrence (log-rank P = 0.008, P < 0.001, P = 0.015, P < 0.001, P = 0.001). Multivariate analysis results showed that Ki-67 lower expression (hazard ratio [HR] = 0.585, 95% confidence interval [CI] = 0.146-2.336, P = 0.448), medium expression (HR = 0.256, 95% CI = 0.084-0.784, P = 0.017), and high expression (HR = 1 as a reference) together with the initial World Health Organization grade (HR = 0.148, 95% CI = 0.029-0.749, P = 0.021) were independent predictive factors for glioma recurrence. CONCLUSIONS: This comprehensive analysis revealed that initial World Health Organization grade and Ki-67 proliferative index were independent prognostic factors that predict the time to recurrence of glioma in patients after first surgery.


Assuntos
Neoplasias Encefálicas/cirurgia , Glioma/cirurgia , Recidiva Local de Neoplasia/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , China/epidemiologia , Metilases de Modificação do DNA/metabolismo , Enzimas Reparadoras do DNA/metabolismo , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Glioma/metabolismo , Glioma/patologia , Humanos , Isocitrato Desidrogenase/metabolismo , Antígeno Ki-67/metabolismo , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Análise de Sobrevida , Fatores de Tempo , Carga Tumoral , Proteína Supressora de Tumor p53/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Proteína Nuclear Ligada ao X/metabolismo , Adulto Jovem
20.
Biochimie ; 160: 148-155, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30876971

RESUMO

Monomeric isocitrate dehydrogenases (IDHs) have once been proposed to be exclusively NADP+-specific. Intriguingly, we recently have reported an NAD+-specific monomeric IDH from Campylobacter sp. FOBRC14 (CaIDH). Moreover, bioinformatic analysis revealed at least three different coenzyme-binding motifs among Campylobacter IDHs. Besides the NAD+-binding motif in CaIDH (Leu584/Asp595/Ser644), a typical NADP+-binding motif was also identified in Campylobacter corcagiensis IDH (CcoIDH, His582/Arg593/Arg638). Meanwhile, a third putative NAD+-binding motif was found in Campylobacter concisus IDH (CcIDH, Leu580/Leu591/Ala640). In this study, CcIDH was overexpressed in Escherichia coli and purified to homogeneity. Gel filtration chromatography demonstrated that the recombinant CcIDH exists as a monomer in solution. Kinetic analysis showed that the Km value of CcIDH for NADP+ was over 49-fold higher than that for NAD+ and the catalytic efficiency (kcat/Km) of CcIDH is 115-fold greater for NAD+ than NADP+. Thus, CcIDH is indeed an NAD+-specific enzyme. However, the catalytic efficiency (kcat/Km = 0.886 µM-1 s-1) of CcIDH for NAD+ is much lower (<5%) when compared to that of the typical monomeric NADP-IDHs for NADP+. Then, the three core NAD+-binding sites were evaluated by site-directed mutagenesis. The mutant CcIDH (H580R591R640) showed a 51-fold higher Km value for NAD+ and 21-fold lower Km value for NADP+ as compared to that of the wild type enzyme, respectively. The overall specificity of the mutant CcIDH was 12-fold greater for NADP+ than that for NAD+. Thus, the coenzyme specificity of CcIDH was converted from NAD+ to NADP+. Isocitrate dependence of enzyme kinetics showed that although the mutant H580R591R640 preferred NADP+ as its coenzyme, its catalytic efficiency for isocitrate reduced to half of that for the wild-type CcIDH as using NAD+. The finding of both NAD+ and NADP+-binding sites in monomeric IDHs from Campylobacter species will provide us a chance to explore the evolution of the coenzyme specificity in monomeric IDH subfamily.


Assuntos
Campylobacter/enzimologia , Isocitrato Desidrogenase/metabolismo , NADP/metabolismo , NAD/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Isocitrato Desidrogenase/genética , Cinética , Mutagênese Sítio-Dirigida , Mutação , Ligação Proteica , Homologia de Sequência de Aminoácidos , Especificidade por Substrato
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