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1.
Microrna ; 7(2): 115-119, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29564990

RESUMO

BACKGROUND: Circulating cell-free miRNAs hold great promise as a new class of biomarkers due to their high stability in body fluids and association with disease stages. However, even using sensitive and specific methods, technical challenges are associated with miRNA analysis in body fluids. A major source of variation in plasma and serum is the potential cell-derived miRNA contamination from hemolysis. OBJECTIVES: The study aimed to evaluate the effect of the delayed whole blood processing time on the concentrations of miR-1 and -423-5p. METHODS: Ten blood samples were incubated for 0, 3 and 24 hours at room temperature prior to processing into plasma. For each time point, hemolysis was assessed in plasma by UV spectrophotometry at 414nm wavelength (λ414). Circulating levels of miR-1 and -423-5p were measured by RT-qPCR; miR-23a and -451 were also analyzed as controls. RESULTS: A significant hemolysis was observed only after 24h (λ414 0.3 ± 0.02, p < 0.001). However, only small changes in miR-1 and -423-5p levels were observed up to 24h of storage at room temperature (Ct 31.5 ± 0.5 to 31.8 ± 0.6for miR-1, p = 0.989; and 29.01 ± 0.3 to 29.04 ± 0.3, p = 0.614 for - 423-5p). No correlation was observed between hemolysis and the levels of miR-1 and -423-5p. CONCLUSION: Our data indicate that the storage of whole blood samples at room temperature for up to 24h prior to their processing into plasma does not appear to have a significant impact on miR-1 and - 423-5p concentrations.


Assuntos
Análise Química do Sangue , Cardiotoxicidade/sangue , MicroRNAs/sangue , Manejo de Espécimes/métodos , Neoplasias da Mama/sangue , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Feminino , Hemólise , Humanos , MicroRNAs/genética , Pessoa de Meia-Idade , Estabilidade de RNA , Fatores de Tempo
2.
J Am Coll Cardiol ; 71(20): 2281-2290, 2018 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-29540327

RESUMO

BACKGROUND: Anthracycline (ANT) chemotherapy is associated with cardiotoxicity. Prevention with ß-blockers remains controversial. OBJECTIVES: This prospective, randomized, double-blind, placebo-controlled study sought to evaluate the role of carvedilol in preventing ANT cardiotoxicity. METHODS: The authors randomized 200 patients with HER2-negative breast cancer tumor status and normal left ventricular ejection fraction (LVEF) referred for ANT (240 mg/m2) to receive carvedilol or placebo until chemotherapy completion. The primary endpoint was prevention of a ≥10% reduction in LVEF at 6 months. Secondary outcomes were effects of carvedilol on troponin I, B-type natriuretic peptide, and diastolic dysfunction. RESULTS: Primary endpoint occurred in 14 patients (14.5%) in the carvedilol group and 13 patients (13.5%) in the placebo group (p = 1.0). No differences in changes of LVEF or B-type natriuretic peptide were noted between groups. A significant difference existed between groups in troponin I levels over time, with lower levels in the carvedilol group (p = 0.003). Additionally, a lower incidence of diastolic dysfunction was noted in the carvedilol group (p = 0.039). A nonsignificant trend toward a less-pronounced increase in LV end-diastolic diameter during the follow-up was noted in the carvedilol group (44.1 ± 3.64 mm to 45.2 ± 3.2 mm vs. 44.9 ± 3.6 mm to 46.4 ± 4.0 mm; p = 0.057). CONCLUSIONS: In this largest clinical trial of ß-blockers for prevention of cardiotoxicity under contemporary ANT dosage, the authors noted a 13.5% to 14.5% incidence of cardiotoxicity. In this scenario, carvedilol had no impact on the incidence of early onset of LVEF reduction. However, the use of carvedilol resulted in a significant reduction in troponin levels and diastolic dysfunction. (Carvedilol Effect in Preventing Chemotherapy-Induced Cardiotoxicity [CECCY]; NCT01724450).

4.
Clin Infect Dis ; 65(7): 1103-1111, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28575239

RESUMO

Background: Chagas disease, caused by the protozoan Trypanosoma cruzi, is endemic in Latin America and affects 10 million people worldwide. Approximately 12000 deaths attributable to Chagas disease occur annually due to chronic Chagas disease cardiomyopathy (CCC), an inflammatory cardiomyopathy presenting with heart failure and arrythmia; 30% of infected subjects develop CCC years after infection. Genetic mechanisms play a role in differential progression to CCC, but little is known about the role of epigenetic modifications in pathological gene expression patterns in CCC patients' myocardium. DNA methylation is the most common modification in the mammalian genome. Methods: We investigated the impact of genome-wide cardiac DNA methylation on global gene expression in myocardial samples from end-stage CCC patients, compared to control samples from organ donors. Results: In total, 4720 genes were differentially methylated between CCC patients and controls, of which 399 were also differentially expressed. Several of them were related to heart function or to the immune response and had methylation sites in their promoter region. Reporter gene and in silico transcription factor binding analyses indicated promoter methylation modified expression of key genes. Among those, we found potassium channel genes KCNA4 and KCNIP4, involved in electrical conduction and arrythmia, SMOC2, involved in matrix remodeling, as well as enkephalin and RUNX3, potentially involved in the increased T-helper 1 cytokine-mediated inflammatory damage in heart. Conclusions: Results support that DNA methylation plays a role in the regulation of expression of pathogenically relevant genes in CCC myocardium, and identify novel potential disease pathways and therapeutic targets in CCC.

5.
Oncotarget ; 8(4): 6994-7002, 2017 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-28052002

RESUMO

Cardiotoxicity is associated with the chronic use of doxorubicin leading to cardiomyopathy and heart failure. Identification of cardiotoxicity-specific miRNA biomarkers could provide clinicians with a valuable prognostic tool. The aim of the study was to evaluate circulating levels of miRNAs in breast cancer patients receiving doxorubicin treatment and to correlate with cardiac function. This is an ancillary study from "Carvedilol Effect on Chemotherapy-induced Cardiotoxicity" (CECCY trial), which included 56 female patients (49.9±3.3 years of age) from the placebo arm. Enrolled patients were treated with doxorubicin followed by taxanes. cTnI, LVEF, and miRNAs were measured periodically. Circulating levels of miR-1, -133b, -146a, and -423-5p increased during the treatment whereas miR-208a and -208b were undetectable. cTnI increased from 6.6±0.3 to 46.7±5.5 pg/mL (p<0.001), while overall LVEF tended to decrease from 65.3±0.5 to 63.8±0.9 (p=0.053) over 12 months. Ten patients (17.9%) developed cardiotoxicity showing a decrease in LVEF from 67.2±1.0 to 58.8±2.7 (p=0.005). miR-1 was associated with changes in LVEF (r=-0.531, p<0.001). In a ROC curve analysis miR-1 showed an AUC greater than cTnI to discriminate between patients who did and did not develop cardiotoxicity (AUC = 0.851 and 0.544, p= 0.0016). Our data suggest that circulating miR-1 might be a potential new biomarker of doxorubicin-induced cardiotoxicity in breast cancer patients.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Cardiotoxicidade/genética , Doxorrubicina/efeitos adversos , MicroRNAs/sangue , Biomarcadores , Neoplasias da Mama/sangue , Neoplasias da Mama/genética , Carbazóis , Cardiotoxicidade/sangue , Cardiotoxicidade/fisiopatologia , Carvedilol , Feminino , Humanos , Pessoa de Meia-Idade , Prognóstico , Propanolaminas , Curva ROC , Volume Sistólico/efeitos dos fármacos , Troponina C/metabolismo , Função Ventricular Esquerda/efeitos dos fármacos
6.
J Infect Dis ; 215(3): 387-395, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28003350

RESUMO

Chagas disease, caused by the protozoan parasite Trypanosoma cruzi, affects 7 million people in Latin American areas of endemicity. About 30% of infected patients will develop chronic Chagas cardiomyopathy (CCC), an inflammatory cardiomyopathy characterized by hypertrophy, fibrosis, and myocarditis. Further studies are necessary to understand the molecular mechanisms of disease progression. Transcriptome analysis has been increasingly used to identify molecular changes associated with disease outcomes. We thus assessed the whole-blood transcriptome of patients with Chagas disease. Microarray analysis was performed on blood samples from 150 subjects, of whom 30 were uninfected control patients and 120 had Chagas disease (1 group had asymptomatic disease, and 2 groups had CCC with either a preserved or reduced left ventricular ejection fraction [LVEF]). Each Chagas disease group displayed distinct gene expression and functional pathway profiles. The most different expression patterns were between CCC groups with a preserved or reduced LVEF. A more stringent analysis indicated that 27 differentially expressed genes, particularly those related to natural killer (NK)/CD8+ T-cell cytotoxicity, separated the 2 groups. NK/CD8+ T-cell cytotoxicity could play a role in determining Chagas disease progression. Understanding genes associated with disease may lead to improved insight into CCC pathogenesis and the identification of prognostic factors for CCC progression.


Assuntos
Cardiomiopatia Chagásica/genética , Disfunção Ventricular/genética , Linfócitos T CD8-Positivos/imunologia , Cardiomiopatia Chagásica/sangue , Cardiomiopatia Chagásica/fisiopatologia , Citotoxicidade Imunológica/genética , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Células Matadoras Naturais/imunologia , Análise em Microsséries , Pessoa de Meia-Idade , Miocárdio/patologia , Reação em Cadeia da Polimerase em Tempo Real , Disfunção Ventricular/sangue , Disfunção Ventricular/parasitologia
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