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1.
Br J Haematol ; 204(1): 206-220, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37726227

RESUMO

Progression to aggressive secondary acute myeloid leukaemia (sAML) poses a significant challenge in the management of myeloproliferative neoplasms (MPNs). Since the physiopathology of MPN is closely linked to the activation of interferon (IFN) signalling and that AML initiation and aggressiveness is driven by leukaemia stem cells (LSCs), we investigated these pathways in MPN to sAML progression. We found that high IFN signalling correlated with low LSC signalling in MPN and AML samples, while MPN progression and AML transformation were characterized by decreased IFN signalling and increased LSC signature. A high LSC to IFN expression ratio in MPN patients was associated with adverse clinical prognosis and higher colony forming potential. Moreover, treatment with hypomethylating agents (HMAs) activates the IFN signalling pathway in MPN cells by inducing a viral mimicry response. This response is characterized by double-stranded RNA (dsRNA) formation and MDA5/RIG-I activation. The HMA-induced IFN response leads to a reduction in LSC signature, resulting in decreased stemness. These findings reveal the frequent evasion of viral mimicry during MPN-to-sAML progression, establish the LSC-to-IFN expression ratio as a progression biomarker, and suggests that HMAs treatment can lead to haematological response in murine models by re-activating dsRNA-associated IFN signalling.


Assuntos
Leucemia Mieloide Aguda , Transtornos Mieloproliferativos , Humanos , Animais , Camundongos , Transtornos Mieloproliferativos/tratamento farmacológico , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/complicações , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Prognóstico , Biomarcadores , Interferons/uso terapêutico
2.
Invest New Drugs ; 40(3): 576-585, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35015172

RESUMO

BACKGROUND: Myeloproliferative neoplasms (MPN) are disorders characterized by an alteration at the hematopoietic stem cell (HSC) level, where the JAK2 mutation is the most common genetic alteration found in classic MPN (polycythemia vera, essential thrombocythemia, and primary myelofibrosis). We and others previously demonstrated that metformin reduced splenomegaly and platelets counts in peripheral blood in JAK2V617F pre-clinical MPN models, which highlighted the antineoplastic potential of biguanides for MPN treatment. Phenformin is a biguanide that has been used to treat diabetes, but was withdrawn due to its potential to cause lactic acidosis in patients. AIMS: We herein aimed to investigate the effects of phenformin in MPN disease burden and stem cell function in Jak2V617F-knockin MPN mice. RESULTS: In vitro phenformin treatment reduced cell viability and increased apoptosis in SET2 JAK2V67F cells. Long-term treatment with 40 mg/kg phenformin in Jak2V617F knockin mice increased the frequency of LSK, myeloid progenitors (MP), and multipotent progenitors (MPP) in the bone marrow. Phenformin treatment did not affect peripheral blood counts, spleen weight, megakaryocyte count, erythroid precursors frequency, or ex vivo clonogenic capacity. Ex vivo treatment of bone marrow cells from Jak2V617F knockin mice with phenformin did not affect hematologic parameters or engraftment in recipient mice. CONCLUSIONS: Phenformin increased the percentages of LSK, MP, and MPP populations, but did not reduce disease burden in Jak2V617F-knockin mice. Additional studies are necessary to further understand the effects of phenformin on early hematopoietic progenitors.


Assuntos
Transtornos Mieloproliferativos , Policitemia Vera , Animais , Medula Óssea , Modelos Animais de Doenças , Humanos , Janus Quinase 2 , Camundongos , Mutação , Transtornos Mieloproliferativos/tratamento farmacológico , Fenformin/farmacologia , Fenformin/uso terapêutico , Policitemia Vera/genética
3.
Nutrients ; 12(5)2020 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-32466231

RESUMO

Based on the fact that taurine can increase lipid metabolism, the objective of the present study was to evaluate the effects of different doses of acute taurine supplementation on lipid oxidation levels in healthy young men after a single bout of fasting aerobic exercise. A double-blind, acute, and crossover study design was conducted. Seventeen men (age 24.8 ± 4.07y; BMI: 23.9 ± 2.57 kg/m²) participated in the present study. Different doses of taurine (TAU) (3 g or 6 g) or placebo were supplemented 90 minutes before a single bout of fasting aerobic exercise (on a treadmill at 60% of VO2 max). The subjects performed three trials, and each one was separated by seven days. Blood samples were collected at baseline and after the exercise protocol of each test to analyze plasma levels of glycerol and taurine. Lipid and carbohydrate oxidation were determined immediately after exercise for 15 minutes by indirect calorimetry. We observed that TAU supplementation (6 g) increased lipid oxidation (38%) and reduced the respiratory coefficient (4%) when compared to the placebo (p < 0.05). However, no differences in lipid oxidation were observed between the different doses of taurine (3 g and 6 g). For glycerol concentrations, there were no differences between trials. Six grams of TAU supplementation 90 minutes before a single bout of aerobic exercise in a fasted state was sufficient to increase the lipid oxidation post-exercise in healthy young men.


Assuntos
Suplementos Nutricionais , Exercício Físico , Jejum , Metabolismo dos Lipídeos/efeitos dos fármacos , Taurina/administração & dosagem , Adulto , Índice de Massa Corporal , Peso Corporal , Calorimetria Indireta , Estudos Cross-Over , Método Duplo-Cego , Teste de Esforço , Humanos , Masculino , Oxirredução/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Taurina/sangue , Adulto Jovem
4.
Asian Pac J Cancer Prev ; 18(5): 1371-1376, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28612588

RESUMO

Introduction: Human papillomavirus (HPV), belonging to the Papovavirida family, is the most prevalent sexually transmitted disease (STD) agent worldwide. In Brazil, it is estimated that there are 3-6 million people infected with HPV. Aim: The aim of this study was to evaluate the knowledge of young male students about penis cancer related to HPV infection. Methods: This exploratory and quantitative study was conducted to analyze answers of 242 male students attending a private college located in Uberaba city, Minas Gerais state, Brazil, during 2015. Results: Most of the 242 participants (88.8%) affirmed having started sexual life very early, the majority (79.3%) were currently married and 69.8% had a single sexual partner. Regardless of their knowledge about HPV virus and its relationship with penis cancer, our data showed a general lack of awareness of the participants. Conclusion: Our results suggest that despite efforts to propagate information about HPV infection and its relation to penis cancer, the level of knowledge of students is low. Because of that, it is important to improve the information spread by media, emphasizing prevention and treatment of HPV infection in men.

5.
Rev Bras Ginecol Obstet ; 37(11): 516-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26561241

RESUMO

PURPOSE: To investigate the frequencies of polymorphic allele and genotypes for the LT-α gene, position +252 (rs909253), in Brazilian women with preeclampsia. METHODS: This is a case-control study, in which 30 women with preeclampsia, classified according to the criteria of the National High Blood Pressure Education Program, and 115 women in the control group, with at least two healthy pregnancies, were selected. Peripheral blood was collected, and DNA was extracted, followed by genotyping, using specific primers and restriction analysis. The genotypes obtained were AA, AG and GG. Statistical analysis was performed using the χ2 association test. The Hardy-Weinberg Equilibrium was tested using the Haploview Program. RESULTS: The results showed no association between genotypes and preeclampsia development (χ2=2.0; p=0.4). When the AG and GG genotypes were grouped according to allele G presence or absence (genotype AA), the data showed that the presence of allele G was not significantly different between cases (women with preeclampsia) and controls (χ2=0.0; p=1.0). The LT-α gene polymorphism, position +252 (rs909253), seems not to be an important candidate for the development of preeclampsia. Other inflammatory genes should be researched, and studies involving gene-environment interactions should be performed, in order to reach a better understanding of the etiology of the preeclampsia.


Assuntos
Linfotoxina-alfa/genética , Polimorfismo Genético , Pré-Eclâmpsia/genética , Adulto , Brasil , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Humanos , Gravidez
6.
Rev. bras. ginecol. obstet ; 37(11): 516-519, tab
Artigo em Inglês | LILACS | ID: lil-764633

RESUMO

PURPOSE: To investigate the frequencies of polymorphic allele and genotypes for the LT-α gene, position +252 (rs909253), in Brazilian women with preeclampsia.METHODS: This is a case-control study, in which 30 women with preeclampsia, classified according to the criteria of the National High Blood Pressure Education Program, and 115 women in the control group, with at least two healthy pregnancies, were selected. Peripheral blood was collected, and DNA was extracted, followed by genotyping, using specific primers and restriction analysis. The genotypes obtained were AA, AG and GG. Statistical analysis was performed using the χ2association test. The Hardy-Weinberg Equilibrium was tested using the Haploview Program.RESULTS: The results showed no association between genotypes and preeclampsia development (χ2=2.0; p=0.4). When the AG and GG genotypes were grouped according to allele G presence or absence (genotype AA), the data showed that the presence of allele G was not significantly different between cases (women with preeclampsia) and controls (χ2=0.0; p=1.0). The LT-α gene polymorphism, position +252 (rs909253), seems not to be an important candidate for the development of preeclampsia. Other inflammatory genes should be researched, and studies involving gene-environment interactions should be performed, in order to reach a better understanding of the etiology of the preeclampsia.


OBJETIVO: Investigar as frequências do alelo polimórfico e genótipos para o gene da LT-α, posição +252 (rs909253), em mulheres brasileiras com pré-eclâmpsia.MÉTODOS: Trata-se de um estudo caso-controle, em que 30 mulheres com pré-eclâmpsia, classificadas de acordo com os critérios do National High Blood Pressure Education Program, e 115 mulheres do grupo controle, com pelo menos duas gestações saudáveis, foram selecionadas. Amostra de sangue periférico foi colhida, e o DNA foi extraído, seguido pela genotipagem, usando iniciadores específicos e análise de restrição. Os genótipos obtidos foram AA, AG e GG. A análise estatística foi realizada utilizando-se o teste de associação χ2. O Equilíbrio de Hardy-Weinberg foi testado com o auxílio do programa Haploview.RESULTADOS: Os resultados não mostraram associação entre os genótipos e o desenvolvimento de pré-eclâmpsia (χ2=2,0; p=0,4). Quando os genótipos AG e GG foram agrupados de acordo com a presença do alelo G ou ausência (genótipo AA), os dados mostraram que a presença do alelo G não foi significativamente diferente entre casos (mulheres com pré-eclâmpsia) e controles (χ2=0,0; p=1,0). O polimorfismo no gene LT-α, posição +252 (rs909253), parece não ser um importante candidato para o desenvolvimento de pré-eclâmpsia. Outros genes inflamatórios devem ser pesquisados, e estudos envolvendo interações gene-ambiente devem ser realizados para que se possa alcançar um melhor entendimento da etiologia da pré-eclâmpsia.


Assuntos
Humanos , Feminino , Gravidez , Adulto , Linfotoxina-alfa/genética , Polimorfismo Genético , Pré-Eclâmpsia/genética , Brasil , Estudos de Casos e Controles , Predisposição Genética para Doença
7.
Rev Bras Ginecol Obstet ; 36(10): 456-60, 2014 Oct.
Artigo em Português | MEDLINE | ID: mdl-25317824

RESUMO

PURPOSE: To identify the frequency of polymorphism in the IL-10 gene, rs1800896 (-1082 A/G), in women with preeclampsia (PE) and in women in a control group and to associate the presence of this polymorphism with protection against the development of PE. METHODS: This was a case-control study conducted on 54 women with PE, classified according to the criteria of the National High Blood Pressure Education Program, and on 172 control women with at least two healthy pregnancies. The proposed polymorphism was studied by the technique of real time polymerase chain reaction (qPCR), with hydrolysis probes. Statistical analysis was performed using the χ2 test. Odds ratio and confidence interval of 95% were used to measure the strength of association between the studied polymorphism and the development of PE. RESULTS: Statistically increased frequency of the AG genotype was observed among control women (85 versus 15% in women with PE). The G allele was significantly more frequent among control women than PE women (χ2 test, p = 0.01). The odds ratio for carriers of the G allele was 2.13, indicating a lower risk of developing PE compared to non-carriers. CONCLUSIONS: Thus, an association is suggested to occur between the presence of the G allele of the polymorphism in the IL-10 rs1800896 (-1082 A/G) gene and protection against the development of PE. More studies investigating the contribution of these variations and the mechanisms by which they affect the risk of developing PE still need to be undertaken.


Assuntos
Interleucina-10/genética , Polimorfismo Genético , Pré-Eclâmpsia/genética , Adulto , Alelos , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez , Adulto Jovem
8.
Rev. bras. ginecol. obstet ; 36(10): 456-460, 10/2014. tab
Artigo em Português | LILACS | ID: lil-725666

RESUMO

OBJETIVOS: Identificar a frequência do polimorfismo no gene IL-10, rs1800896 (-1082 A/G), em mulheres com pré-eclâmpsia (PE) e em mulheres do grupo controle e associar a presença deste polimorfismo com a proteção contra o desenvolvimento da PE. MÉTODOS: Estudo do tipo caso-controle, no qual foram selecionadas 54 mulheres com PE, classificadas de acordo com os critérios da National High Blood Pressure Education Program e 172 mulheres do grupo controle, com pelo menos duas gestações saudáveis. O polimorfismo proposto foi estudado utilizando-se a técnica de reação em cadeia da polimerase em tempo real (qPCR), com sondas de hidrólise. A análise estatística foi realizada utilizando-se o teste de associação do χ2. Odds ratio e seu intervalo de confiança de 95% foram usados para medir a força de associação entre o polimorfismo estudado e o desenvolvimento da PE. RESULTADOS: Foi observado aumento significativo da frequência do genótipo AG entre mulheres do grupo controle (85 versus 15% nas mulheres com PE). O alelo G é significativamente mais frequente entre as mulheres do grupo controle do que nas com PE (Teste χ2; p=0,01). O odds ratio para as portadoras do alelo G foi de 2, 13, indicando que apresentam menor risco de desenvolver PE do que as não portadoras. CONCLUSÕES: Sugere-se associação entre a presença do alelo G do polimorfismo no gene IL-10, rs1800896 (-1082 A/G), e a proteção contra o desenvolvimento da PE. Mais estudos sobre a contribuição dessas variações e os mecanismos pelos quais afetam o risco de desenvolver PE ainda necessitam de ser realizadas. .


PURPOSE: To identify the frequency of polymorphism in the IL-10 gene, rs1800896 (-1082 A/G), in women with preeclampsia (PE) and in women in a control group and to associate the presence of this polymorphism with protection against the development of PE. METHODS: This was a case-control study conducted on 54 women with PE, classified according to the criteria of the National High Blood Pressure Education Program, and on 172 control women with at least two healthy pregnancies. The proposed polymorphism was studied by the technique of real time polymerase chain reaction (qPCR), with hydrolysis probes. Statistical analysis was performed using the χ2 test. Odds ratio and confidence interval of 95% were used to measure the strength of association between the studied polymorphism and the development of PE. RESULTS: Statistically increased frequency of the AG genotype was observed among control women (85 versus 15% in women with PE). The G allele was significantly more frequent among control women than PE women (χ2 test, p = 0.01). The odds ratio for carriers of the G allele was 2.13, indicating a lower risk of developing PE compared to non-carriers. CONCLUSIONS: Thus, an association is suggested to occur between the presence of the G allele of the polymorphism in the IL-10 rs1800896 (-1082 A/G) gene and protection against the development of PE. More studies investigating the contribution of these variations and the mechanisms by which they affect the risk of developing PE still need to be undertaken. .


Assuntos
Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez , Adulto Jovem , /genética , Polimorfismo Genético , Pré-Eclâmpsia/genética , Alelos , Estudos de Casos e Controles
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