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1.
J Clin Invest ; 134(8)2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38618957

RESUMO

T cell acute lymphoblastic leukemia (T-ALL) is an aggressive immature T cell cancer. Mutations in IL7R have been analyzed genetically, but downstream effector functions such as STAT5A and STAT5B hyperactivation are poorly understood. Here, we studied the most frequent and clinically challenging STAT5BN642H driver in T cell development and immature T cell cancer onset and compared it with STAT5A hyperactive variants in transgenic mice. Enhanced STAT5 activity caused disrupted T cell development and promoted an early T cell progenitor-ALL phenotype, with upregulation of genes involved in T cell receptor (TCR) signaling, even in absence of surface TCR. Importantly, TCR pathway genes were overexpressed in human T-ALL and mature T cell cancers and activation of TCR pathway kinases was STAT5 dependent. We confirmed STAT5 binding to these genes using ChIP-Seq analysis in human T-ALL cells, which were sensitive to pharmacologic inhibition by dual STAT3/5 degraders or ZAP70 tyrosine kinase blockers in vitro and in vivo. We provide genetic and biochemical proof that STAT5A and STAT5B hyperactivation can initiate T-ALL through TCR pathway hijacking and suggest similar mechanisms for other T cell cancers. Thus, STAT5 or TCR component blockade are targeted therapy options, particularly in patients with chemoresistant clones carrying STAT5BN642H.


Assuntos
Leucemia-Linfoma Linfoblástico de Células T Precursoras , Animais , Humanos , Camundongos , Camundongos Transgênicos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Proteínas Tirosina Quinases , Receptores de Antígenos de Linfócitos T/genética , Transdução de Sinais , Fator de Transcrição STAT5/genética
2.
J Therm Spray Technol ; 31(1-2): 269-281, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-38624803

RESUMO

A typical structure of thermal spray coatings consisted of molten particles, semi-molten particles, oxides, pores, and cracks. These factors caused the porosity of sprayed coatings, leading to a significant influence on the coating properties, especially their wear-corrosion resistance. In this study, a post-spray sealing treatment of Cr3C2-NiCr/Al2O3-TiO2 plasma-sprayed coatings was carried out, and then, their corrosion properties were evaluated, before and after the treatment. For the sealing process, aluminum phosphate (APP) containing Al2O3 nanoparticles (~10 nm) was used. The permeability of APP into the sprayed coating was analyzed by SEM-EDS. The treatment efficiency for porosity and corrosion resistance of sprayed coatings was evaluated by electrochemical measurements, such as the potentiodynamic polarization and electrochemical impedance spectroscopy. The wear-corrosion resistance of the coating was examined in 3.5 wt.% NaCl circulation solution containing 0.25% SiO2 particles. The sealing efficiency was evaluated by the percentage of the treated open pores in the coating. The obtained results showed that APP penetrated deeply through the coating and the incorporation of Al2O3 nanoparticles into APP sealant improved the sealing efficiency by 20% of open pores in comparison with the sealant without nano-Al2O3. The effect of the post-treatment on corrosion protection of the sprayed coating has been discussed.

3.
Blood ; 136(4): 387-400, 2020 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-32344427

RESUMO

Fusion proteins involving Nucleoporin 98 (NUP98) are recurrently found in acute myeloid leukemia (AML) and are associated with poor prognosis. Lack of mechanistic insight into NUP98-fusion-dependent oncogenic transformation has so far precluded the development of rational targeted therapies. We reasoned that different NUP98-fusion proteins deregulate a common set of transcriptional targets that might be exploitable for therapy. To decipher transcriptional programs controlled by diverse NUP98-fusion proteins, we developed mouse models for regulatable expression of NUP98/NSD1, NUP98/JARID1A, and NUP98/DDX10. By integrating chromatin occupancy profiles of NUP98-fusion proteins with transcriptome profiling upon acute fusion protein inactivation in vivo, we defined the core set of direct transcriptional targets of NUP98-fusion proteins. Among those, CDK6 was highly expressed in murine and human AML samples. Loss of CDK6 severely attenuated NUP98-fusion-driven leukemogenesis, and NUP98-fusion AML was sensitive to pharmacologic CDK6 inhibition in vitro and in vivo. These findings identify CDK6 as a conserved, critical direct target of NUP98-fusion proteins, proposing CDK4/CDK6 inhibitors as a new rational treatment option for AML patients with NUP98-fusions.


Assuntos
Quinase 6 Dependente de Ciclina/metabolismo , Sistemas de Liberação de Medicamentos , Leucemia Mieloide Aguda/metabolismo , Complexo de Proteínas Formadoras de Poros Nucleares/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , Animais , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/genética , Perfilação da Expressão Gênica , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Camundongos , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Proteínas de Fusão Oncogênica/genética
4.
Haematologica ; 105(2): 435-447, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31123029

RESUMO

Recurrent gain-of-function mutations in the transcription factors STAT5A and much more in STAT5B were found in hematopoietic malignancies with the highest proportion in mature T- and natural killer-cell neoplasms (peripheral T-cell lymphoma, PTCL). No targeted therapy exists for these heterogeneous and often aggressive diseases. Given the shortage of models for PTCL, we mimicked graded STAT5A or STAT5B activity by expressing hyperactive Stat5a or STAT5B variants at low or high levels in the hematopoietic system of transgenic mice. Only mice with high activity levels developed a lethal disease resembling human PTCL. Neoplasia displayed massive expansion of CD8+ T cells and destructive organ infiltration. T cells were cytokine-hypersensitive with activated memory CD8+ T-lymphocyte characteristics. Histopathology and mRNA expression profiles revealed close correlation with distinct subtypes of PTCL. Pronounced STAT5 expression and activity in samples from patients with different subsets underline the relevance of JAK/STAT as a therapeutic target. JAK inhibitors or a selective STAT5 SH2 domain inhibitor induced cell death and ruxolitinib blocked T-cell neoplasia in vivo We conclude that enhanced STAT5A or STAT5B action both drive PTCL development, defining both STAT5 molecules as targets for therapeutic intervention.


Assuntos
Leucemia , Linfoma de Células T Periférico , Animais , Linfócitos T CD8-Positivos/metabolismo , Citocinas , Humanos , Linfoma de Células T Periférico/genética , Camundongos , Fator de Transcrição STAT5/genética , Fator de Transcrição STAT5/metabolismo , Proteínas Supressoras de Tumor
5.
Mol Cell Oncol ; 5(3): e1435181, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29876519

RESUMO

The somatic hot spot mutation STAT5BN642H was found in many T cell leukemia/lymphoma patients. We generated and analyzed a transgenic mouse model with hematopoietic STAT5BN642H expression that caused aggressive T-cell leukemia/lymphomas. Herein, we discuss the scientific merit of our model and its relevance for pre-clinical studies.

6.
J Clin Invest ; 128(1): 387-401, 2018 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-29200404

RESUMO

STAT5B is often mutated in hematopoietic malignancies. The most frequent STAT5B mutation, Asp642His (N642H), has been found in over 90 leukemia and lymphoma patients. Here, we used the Vav1 promoter to generate transgenic mouse models that expressed either human STAT5B or STAT5BN642H in the hematopoietic compartment. While STAT5B-expressing mice lacked a hematopoietic phenotype, the STAT5BN642H-expressing mice rapidly developed T cell neoplasms. Neoplasia manifested as transplantable CD8+ lymphoma or leukemia, indicating that the STAT5BN642H mutation drives cancer development. Persistent and enhanced levels of STAT5BN642H tyrosine phosphorylation in transformed CD8+ T cells led to profound changes in gene expression that were accompanied by alterations in DNA methylation at potential histone methyltransferase EZH2-binding sites. Aurora kinase genes were enriched in STAT5BN642H-expressing CD8+ T cells, which were exquisitely sensitive to JAK and Aurora kinase inhibitors. Together, our data suggest that JAK and Aurora kinase inhibitors should be further explored as potential therapeutics for lymphoma and leukemia patients with the STAT5BN642H mutation who respond poorly to conventional chemotherapy.


Assuntos
Linfócitos T CD8-Positivos/metabolismo , Neoplasias Hematológicas/metabolismo , Leucemia de Células T/metabolismo , Linfoma de Células T/metabolismo , Proteínas de Neoplasias/metabolismo , Fator de Transcrição STAT5/metabolismo , Substituição de Aminoácidos , Animais , Linfócitos T CD8-Positivos/patologia , Metilação de DNA/genética , DNA de Neoplasias/genética , DNA de Neoplasias/metabolismo , Neoplasias Hematológicas/genética , Humanos , Leucemia de Células T/genética , Leucemia de Células T/patologia , Linfoma de Células T/genética , Linfoma de Células T/patologia , Camundongos , Camundongos Transgênicos , Mutação de Sentido Incorreto , Proteínas de Neoplasias/genética , Fator de Transcrição STAT5/genética
7.
Nat Commun ; 8(1): 595, 2017 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-28928383

RESUMO

Controlled invasion is essential during many physiological processes, whereas its deregulation is a hallmark of cancer. Here we demonstrate that embryonic, induced pluripotent and amniotic fluid stem cells share the property to induce the invasion of primary somatic cells of various origins through insulin-like growth factor I (IGF-I)- or II (IGF-II)-mediated paracrine activation of mechanistic target of rapamycin complex 1 (mTORC1). We propose a model in which downstream of mTORC1 this stem cell-induced invasion is mediated by hypoxia-inducible factor 1-alpha (HIF-1α)-regulated matrix metalloproteinases. Manipulating the IGF signalling pathway in the context of teratoma formation experiments demonstrates that human stem cells use this mechanism to induce invasion and thereby attract cells from the microenvironment in vivo. In this study we have identified a so far unknown feature of human stem cells, which might play a role for the development of stem cell-derived tumours.Cell invasion is required for several physiological processes but it is unknown if stem cells induce invasiveness in other cells. Here, the authors show that human stem cells secrete insulin-like growth factor, which in turn activates the mTORC1 pathway, initiating invasive behaviour and attracting other cells.


Assuntos
Carcinoma Embrionário/metabolismo , Células-Tronco Embrionárias Humanas/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Fator de Crescimento Insulin-Like II/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Metaloproteinases da Matriz/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Comunicação Parácrina , Teratoma/metabolismo , Carcinoma Embrionário/patologia , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Células-Tronco Embrionárias Humanas/patologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Células-Tronco Pluripotentes Induzidas/patologia , Fator de Crescimento Insulin-Like I/farmacologia , Fator de Crescimento Insulin-Like II/farmacologia , Metaloproteinases da Matriz/efeitos dos fármacos , Alvo Mecanístico do Complexo 1 de Rapamicina/efeitos dos fármacos , Invasividade Neoplásica , Comunicação Parácrina/efeitos dos fármacos , Transdução de Sinais , Teratoma/patologia
8.
Sci Total Environ ; 605-606: 507-513, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28672239

RESUMO

Arxula adeninivorans-based yeast cell assays for the detection of steroid hormones demonstrated their efficiency for the determination of total hormone activity in a variety of samples using a microtiter plate format. In this study, a preliminary chromatographic separation using thin-layer chromatography plates is introduced in order to allow a rapid identification of the compounds responsible for this hormonal activity. The yeast whole cell assay can then be performed on the plate, producing a detectable signal where a steroid hormone is present. Simultaneous detection of estrogens, progestogens and androgens on the same plate in the picogram range was achieved, while keeping the assay as simple and affordable as possible. The assay requires a single incubation of the thin-layer chromatography plate and the detection of reporter protein production can be performed by fluorescence scanning of the plate at different wavelengths. The chromatographic separation allows the separation of several estrogens, androgens and progestogens, thus making its application for 'real world' samples very useful. In this work, different water-based samples from environmental origins were used to demonstrate the capacity of this new bioassay. Trials showed that most samples, with the exception of complex samples such as wastewater influent, can be assayed.


Assuntos
Androgênios/análise , Bioensaio , Cromatografia em Camada Fina , Estrogênios/análise , Poluentes Químicos da Água/análise , Saccharomycetales , Águas Residuárias/análise
9.
Nat Immunol ; 18(3): 293-302, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28092373

RESUMO

The aggregation of hypertrophic macrophages constitutes the basis of all granulomatous diseases, such as tuberculosis or sarcoidosis, and is decisive for disease pathogenesis. However, macrophage-intrinsic pathways driving granuloma initiation and maintenance remain elusive. We found that activation of the metabolic checkpoint kinase mTORC1 in macrophages by deletion of the gene encoding tuberous sclerosis 2 (Tsc2) was sufficient to induce hypertrophy and proliferation, resulting in excessive granuloma formation in vivo. TSC2-deficient macrophages formed mTORC1-dependent granulomatous structures in vitro and showed constitutive proliferation that was mediated by the neo-expression of cyclin-dependent kinase 4 (CDK4). Moreover, mTORC1 promoted metabolic reprogramming via CDK4 toward increased glycolysis while simultaneously inhibiting NF-κB signaling and apoptosis. Inhibition of mTORC1 induced apoptosis and completely resolved granulomas in myeloid TSC2-deficient mice. In human sarcoidosis patients, mTORC1 activation, macrophage proliferation and glycolysis were identified as hallmarks that correlated with clinical disease progression. Collectively, TSC2 maintains macrophage quiescence and prevents mTORC1-dependent granulomatous disease with clinical implications for sarcoidosis.


Assuntos
Granuloma/imunologia , Macrófagos/imunologia , Complexos Multiproteicos/metabolismo , Sarcoidose/imunologia , Serina-Treonina Quinases TOR/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Linhagem Celular , Quinase 4 Dependente de Ciclina/metabolismo , Progressão da Doença , Granuloma/tratamento farmacológico , Humanos , Macrófagos/efeitos dos fármacos , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , RNA Interferente Pequeno/genética , Sarcoidose/tratamento farmacológico , Transdução de Sinais , Proteína 2 do Complexo Esclerose Tuberosa , Proteínas Supressoras de Tumor/genética
10.
Biotechnol Bioeng ; 114(7): 1539-1549, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28092110

RESUMO

A biosensor detecting estrogens, progestogens, and androgens in complex samples and in a single step is described. Three Arxula adeninivorans yeast strains were created, each strain producing a different recombinant human hormone receptor and a different fluorescent reporter protein. These strains were then mixed to create G1212/YRC102-hHR-fluo, the biological component of the biosensor. During incubation with G1212/YRC102-hHR-fluo, hormones present in a sample bind to their target receptor, which leads to the production of a specific fluorescent protein. Three fluorescence scans of the yeast suspension determine which fluorescence protein has been produced, thus revealing which hormone receptor (estrogen, progesterone, and androgen) has been activated by the hormones or hormone mimics present in the sample. The biosensor has similar sensitivities to the existing A. adeninivorans cell-based assays. The detection of the three hormone classes in one single experiment reduces the labor and time required to assay for the three hormone classes. The biosensor was also trialed with animal serum samples for the detection of progestogens, androgens, and estrogens and gave results that correlated well with ELISA analysis in case of progestogens. These results highlight the potential usefulness of the biosensor for comprehensive determination of hormone status in samples from veterinary origin. Biotechnol. Bioeng. 2017;114: 1539-1549. © 2017 Wiley Periodicals, Inc.


Assuntos
Ascomicetos/classificação , Ascomicetos/efeitos dos fármacos , Bioensaio/instrumentação , Técnicas Biossensoriais/instrumentação , Hormônios Esteroides Gonadais/sangue , Hormônios Esteroides Gonadais/farmacologia , Animais , Callithrix , Desenho de Equipamento , Análise de Falha de Equipamento , Hormônios Esteroides Gonadais/análise , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Especificidade da Espécie , Espectrometria de Fluorescência/instrumentação
11.
Cytokine ; 87: 26-36, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27349799

RESUMO

In the past decades, studies of the Janus kinases (JAKs) and signal transducers and activators of transcription (STATs) signaling have uncovered highly conserved programs linking cytokine signaling to the regulation of essential cellular mechanisms such as proliferation, invasion, survival, inflammation and immunity. Inhibitors of the JAK/STAT pathway are used for treatment of autoimmune diseases, such as rheumatoid arthritis or psoriasis. Aberrant JAK/STAT signaling has been identified to contribute to cancer progression and metastatic development. Targeting of JAK/STAT pathway is currently one of the most promising therapeutic strategies in prostate cancer (PCa), hematopoietic malignancies and sarcomas. Notably, newly identified regulators of JAK/STAT signaling, the non-coding RNAs transcripts and their role as important targets and potential clinical biomarkers are highlighted in this review. In addition to the established role of the JAK/STAT signaling pathway in traditional cytokine signaling the non-coding RNAs add yet another layer of hidden regulation and function. Understanding the crosstalk of non-coding RNA with JAK/STAT signaling in cancer is of critical importance and may result in better patient stratification not only in terms of prognosis but also in the context of therapy.


Assuntos
Citocinas/metabolismo , Janus Quinases/metabolismo , Neoplasias/metabolismo , RNA não Traduzido/metabolismo , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais , Animais , Genoma , Humanos , Masculino , Camundongos , Neoplasias/terapia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/terapia , Sarcoma/metabolismo , Sarcoma/terapia
12.
Anal Bioanal Chem ; 407(26): 8109-20, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26307113

RESUMO

This study describes the development of a bioassay to detect the presence of progesterone and progesterone-like molecules in wastewater samples. The basis of the bioassay is the integration of the human progesterone receptor gene into the yeast Arxula adeninivorans for the constitutive synthesis of the receptor. After incubation, binding of the analyte to the receptor induces the production of a reporter protein. Two reporter proteins were compared for detection parameters such as half-maximal activity (EC50), limit of detection (LoD) and limit of quantification (LoQ). When the extracellular phytase K was used, an EC50 value of 155 ng L(-1) and a LoD of 27 ng L(-1) progesterone were obtained after 4 h incubation, while use of the fluorescent dsRED as the reporter protein, resulted in an EC50 of 320 ng L(-1) and a LoD of 65 ng L(-1) after 20 h incubation. Use of phytase K as the reporter protein offers decreased incubation time and increased sensitivity; however the dsRED reporter system is less labor-intensive. Additionally, the affinity of known agonists and antagonists of the human progesterone receptor was determined. The utility of this bioassay was confirmed by measuring total progesterone equivalent concentration of samples from a wastewater treatment plant. The A. adeninivorans-based transactivation assay was able to measure concentrations of about 311 ng L(-1) in the influent stream but could not detect progesterone activity in effluent. One key feature of the assay is the robustness of A. adeninivorans, which allows sample measurement without any sample preparation.


Assuntos
Progesterona/análise , Receptores de Progesterona/genética , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Leveduras/genética , Clonagem Molecular , Corantes Fluorescentes/análise , Corantes Fluorescentes/metabolismo , Expressão Gênica , Genes Reporter , Humanos , Limite de Detecção , Proteínas Luminescentes/análise , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Progesterona/metabolismo , Receptores de Progesterona/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saccharomycetales/genética , Espectrometria de Fluorescência , Transformação Genética , Poluentes Químicos da Água/metabolismo
13.
J Nutr Sci Vitaminol (Tokyo) ; 54(2): 169-75, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18490848

RESUMO

Over-concern about thinness, especially among young girls including adolescents, is common in Japan. Behind the problem, there is a complicated social phenomenon and an effective strategy is not known yet. In this study, we tried to find a clue by comparing body image between two countries which have different social backgrounds. Subjects were Japanese and Vietnamese junior high school students from 12 to 15 y old. Three schools each and 1-2 classes from each grade were randomly selected to involve 374 (boys 196, girls 178) and 714 (boys 352, girls 362), respectively, in Japan and Vietnam. Height and weight of subjects were measured and their satisfaction about their body shape and experience with dieting were asked by a questionnaire. Questions about their body image concerning their desire, liking of the opposite sex, own liking and health were answered by marking silhouettes. About 60% of Japanese thought that obese (silhouette 9) is unhealthy, while about 85% of Vietnamese thought that thinness (silhouette 1) is unhealthy. Most of the Japanese girls overestimated their body weight and were dissatisfied with their body shape and 78.3% wanted to lose weight. About 30% of them experienced weight loss including 2.8% of the low BMI students. Vietnamese girls also had similar tendencies in their desire about their body image as the Japanese but they were less serious. The girls in both countries preferred the thinner body image to the healthy body image and thought that boys liked the thinner body image. Japanese boys were mostly satisfied with their body shape; however, about half (46%) of the Vietnamese boys wanted a bigger and more muscular body image. In conclusion, the biggest problem with body image was the over-concern about thinness of the Japanese girls, which was based on their own misconception. Therefore, as the strategy to correct their body image, education about good health and also information about the boys' favorite body image are recommended.


Assuntos
Imagem Corporal , Comparação Transcultural , Adolescente , Comportamento do Adolescente/psicologia , Atitude Frente a Saúde , Índice de Massa Corporal , Peso Corporal , Criança , Estudos Transversais , Feminino , Inquéritos Epidemiológicos , Humanos , Japão , Masculino , Satisfação Pessoal , Distribuição por Sexo , Inquéritos e Questionários , Vietnã
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