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1.
Methods Mol Biol ; 2825: 213-237, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38913312

RESUMO

Three-dimensional structured illumination microscopy (3D-SIM) and fluorescence in situ hybridization on three-dimensional preserved cells (3D-FISH) have proven to be robust and efficient methodologies for analyzing nuclear architecture and profiling the genome's topological features. These methods have allowed the simultaneous visualization and evaluation of several target structures at super-resolution. In this chapter, we focus on the application of 3D-SIM for the visualization of 3D-FISH preparations of chromosomes in interphase, known as Chromosome Territories (CTs). We provide a workflow and detailed guidelines for sample preparation, image acquisition, and image analysis to obtain quantitative measurements for profiling chromosome topological features. In parallel, we address a practical example of these protocols in the profiling of CTs 9 and 22 involved in the translocation t(9;22) in Chronic Myeloid Leukemia (CML). The profiling of chromosome topological features described in this chapter allowed us to characterize a large-scale topological disruption of CTs 9 and 22 that correlates directly with patients' response to treatment and as a possible potential change in the inheritance systems. These findings open new insights into how the genome structure is associated with the response to cancer treatments, highlighting the importance of microscopy in analyzing the topological features of the genome.


Assuntos
Imageamento Tridimensional , Hibridização in Situ Fluorescente , Humanos , Hibridização in Situ Fluorescente/métodos , Imageamento Tridimensional/métodos , Translocação Genética , Cromossomos/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Interfase/genética , Cromossomos Humanos/genética , Processamento de Imagem Assistida por Computador/métodos
2.
Arch Pharm (Weinheim) ; 357(8): e2400029, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38627294

RESUMO

Imatinib mesylate was the first representative BCR-ABL1 tyrosine kinase inhibitor (TKI) class for the treatment of chronic myeloid leukemia. Despite the revolution promoted by TKIs in the treatment of this pathology, a resistance mechanism occurs against all BCR-ABL1 inhibitors, necessitating a constant search for new therapeutic options. To develop new antimyeloproliferative substances, we applied a medicinal chemistry tool known as molecular hybridization to design 25 new substances. These compounds were synthesized and biologically evaluated against K562 cells, which express BCR-ABL1, a constitutively active tyrosine kinase enzyme, as well as in WSS-1 cells (healthy cells). The new compounds are conjugated hybrids that contain phenylamino-pyrimidine-pyridine (PAPP) and an isatin backbone, which are the main pharmacophoric fragments of imatinib and sunitinib, respectively. A spiro-oxindole nucleus was used as a linker because it occurs in many compounds with antimyeloproliferative activity. Compounds 2a, 2b, 3c, 4c, and 4e showed promise, as they inhibited cell viability by between 45% and 61% at a concentration of 10 µM. The CC50 of the most active substances was determined to be within 0.8-9.8 µM.


Assuntos
Antineoplásicos , Sobrevivência Celular , Mesilato de Imatinib , Oxindóis , Humanos , Células K562 , Mesilato de Imatinib/farmacologia , Oxindóis/farmacologia , Oxindóis/síntese química , Oxindóis/química , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Sobrevivência Celular/efeitos dos fármacos , Relação Estrutura-Atividade , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Proliferação de Células/efeitos dos fármacos , Estrutura Molecular , Relação Dose-Resposta a Droga , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Proteínas de Fusão bcr-abl/metabolismo , Compostos de Espiro/farmacologia , Compostos de Espiro/química , Compostos de Espiro/síntese química , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Ensaios de Seleção de Medicamentos Antitumorais
3.
Int J Mol Sci ; 25(6)2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38542337

RESUMO

Chronic myeloid leukemia (CML) is a type of leukemia whose main genetic marker is the reciprocal translocation that leads to the production of the BCR::ABL1 oncoprotein. The expression of some genes may interfere with the progression and development of leukemias. MicroRNAs are small non-coding RNAs that have the potential to alter the expression of some genes and may be correlated with some types of leukemia and could be used as biomarkers in the diagnosis and prognosis of patients. Therefore, this project carried out an analysis of microRNA-type plasma biomarkers in patients with chronic myeloid leukemia at unique points, including follow-up analysis of patients from the Erasto Gaertner Hospital. 35 microRNAs were analyzed in different cohorts. Inside those groups, 70 samples were analyzed at unique points and 11 patients in a follow-up analysis. Statistically different results were found for microRNA-7-5p, which was found to be upregulated in patients with high expression of the BCR::ABL1 transcript when compared to healthy controls. This microRNA also had evidence of behavior related to BCR::ABL1 when analyzed in follow-up, but strong evidence was not found. In this way, this work obtained results that may lead to manifestations of a relationship between miR-7-5p and chronic myeloid leukemia, and evaluations of possible microRNAs that are not related to this pathology.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva , MicroRNAs , Humanos , MicroRNAs/genética , Proteínas de Fusão bcr-abl/genética , Proteínas de Fusão bcr-abl/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Translocação Genética , Biomarcadores
4.
Math Biosci Eng ; 20(11): 19504-19526, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-38052612

RESUMO

The aim of this work is to estimate the effect of Imatinib, exosomes, and Imatinib-exosomes mixture in chronic myeloid leukemia (CML). For this purpose, mathematical models based on Gompertzian and logistic growth differential equations were proposed. The models contained parameters representing the effects of the three components on CML proliferation. Parameters estimation was performed under the Bayesian statistical approach. Experimental data reported in the literature were used, corresponding to four trials of a human leukemia xenograft in BALB/c female rats over a period of forty days. The models were fitted to the following growth dynamics: normal tumor growth, growth with exosomes, growth with Imatinib, and growth with exosomes-Imatinib mixture. For the proposed logistic growth model, it was determined that when using Imatinib treatment the growth rate is 0.93 (95% CrI: 84.33-99.64) slower and reduces the tumor volume to approximately 10% (95% CrI : 8.67-10.81). In the presence of exosome treatment, the growth rate is 0.83 (95% CrI: 1.52-16.59) faster and the tumor volume is expanded by 40% (95% CrI: 25.36-57.28). Finally, in the presence of Imatinib-exosomes mixture treatment, the growth rate is 0.82 (95% CrI: 76.87-88.51) slower and the tumor volume is reduced by 95% (95% CrI: 86.76-99.85). It is concluded that the presence of exosomes partially inactivates the effect of the Imatinib drug on tumor growth in a mouse xenograft model.


Assuntos
Antineoplásicos , Exossomos , Leucemia Mielogênica Crônica BCR-ABL Positiva , Humanos , Feminino , Camundongos , Ratos , Animais , Mesilato de Imatinib/farmacologia , Mesilato de Imatinib/uso terapêutico , Teorema de Bayes , Xenoenxertos , Exossomos/patologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico
5.
Med Oncol ; 38(9): 100, 2021 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-34302533

RESUMO

The Estudo de Descontinuação de Imatinibe após Pioglitazona (EDI-PIO) is a single-center, longitudinal, prospective, phase 2, non-randomized, open, clinical trial (NCT02852486, August 2, 2016 retrospectively registered) for the discontinuation of imatinib after concomitant use of pioglitazone, being the first of its kind in a Brazilian population with chronic myeloid leukemia. Due to remaining of leukemic quiescent cells that are not affected by tyrosine kinase inhibitors, it has been suggested the use of pioglitazone, a PPARγ agonist, together with imatinib as a strategy for the maintenance of deep molecular response. The clinical benefit to this association is still controversial, and the metabolic alteration along this process remains unclear. Therefore, we applied a metabolomic protocol using high-resolution mass spectrometry to profile plasmatic metabolic response of a prospective cohort of ten individuals under discontinuation of imatinib and pioglitazone protocol. By comparing patients under pioglitazone and imatinib treatment with imatinib monotherapy and discontinuation phase, we were able to annotate 41 and 36 metabolites, respectively. The metabolic alterations observed during imatinib-pioglitazone combined therapy are associated with an extensive lipid remodeling, with activation of ß-oxidation pathway, in addition to the presence of markers that suggest mitochondrial dysfunction.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Biomarcadores Tumorais/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Doenças Metabólicas/patologia , Metaboloma , Suspensão de Tratamento , Adulto , Idoso , Feminino , Seguimentos , Humanos , Mesilato de Imatinib/administração & dosagem , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Estudos Longitudinais , Masculino , Doenças Metabólicas/induzido quimicamente , Doenças Metabólicas/metabolismo , Pessoa de Meia-Idade , Ensaios Clínicos Controlados não Aleatórios como Assunto , Pioglitazona/administração & dosagem , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , Adulto Jovem
6.
Molecules ; 26(4)2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33578817

RESUMO

Multidrug resistance (MDR) is the main challenge in the treatment of chronic myeloid leukemia (CML), and P-glycoprotein (P-gp) overexpression is an important mechanism involved in this resistance process. However, some compounds can selectively affect MDR cells, inducing collateral sensitivity (CS), which may be dependent on P-gp. The aim of this study was to investigate the effect of piperine, a phytochemical from black pepper, on CS induction in CML MDR cells, and the mechanisms involved. The results indicate that piperine induced CS, being more cytotoxic to K562-derived MDR cells (Lucena-1 and FEPS) than to K562, the parental CML cell. CS was confirmed by analysis of cell metabolic activity and viability, cell morphology and apoptosis. P-gp was partially required for CS induction. To investigate a P-gp independent mechanism, we analyzed the possibility that poly (ADP-ribose) polymerase-1 (PARP-1) could be involved in piperine cytotoxic effects. It was previously shown that only MDR FEPS cells present a high level of 24 kDa fragment of PARP-1, which could protect these cells against cell death. In the present study, piperine was able to decrease the 24 kDa fragment of PARP-1 in MDR FEPS cells. We conclude that piperine targets selectively MDR cells, inducing CS, through a mechanism that might be dependent or not on P-gp.


Assuntos
Alcaloides/farmacologia , Apoptose , Benzodioxóis/farmacologia , Inibidores das Enzimas do Citocromo P-450/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Piperidinas/farmacologia , Alcamidas Poli-Insaturadas/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Sobrevivência Celular , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo
7.
Autops. Case Rep ; 11: e2021339, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1345358

RESUMO

Myeloid sarcoma (MS) is a rare extramedullary neoplasm of myeloid cells, which can arise before, concurrently with, or following hematolymphoid malignancies. We report 04 such cases of MS, diagnosed in this institute over a period of 6 years, during various phases of their respective myeloid neoplasms/leukemias. These cases include MS occurring as a relapse of AML (Case 1), MS occurring as an initial presentation of CML (Case 2), MS occurring during ongoing chemotherapy in APML (Case 3), and MS presenting as a progression of MDS to AML (Case 4). In the absence of relevant clinical history and unemployment of appropriate immunohistochemical (IHC) studies, these cases have a high risk of being frequently misdiagnosed either as Non-Hodgkin's Lymphoma (NHL) or small round cell tumors or undifferentiated carcinomas, which may further delay their management, making an already bad prognosis worse. This case series has been designed to throw light on the varied presentation of MS and the lineage differentiation of its neoplastic cells through the application of relevant IHC markers along with their clinical correlation.


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Adolescente , Pessoa de Meia-Idade , Idoso , Sarcoma Mieloide/patologia , Síndromes Mielodisplásicas/patologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Leucemia Mieloide Aguda/patologia , Leucemia Promielocítica Aguda/patologia , Erros de Diagnóstico/prevenção & controle
9.
J Biol Chem ; 295(19): 6457-6471, 2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32229586

RESUMO

Multidrug resistance (MDR) in cancer arises from cross-resistance to structurally- and functionally-divergent chemotherapeutic drugs. In particular, MDR is characterized by increased expression and activity of ATP-binding cassette (ABC) superfamily transporters. Sphingolipids are substrates of ABC proteins in cell signaling, membrane biosynthesis, and inflammation, for example, and their products can favor cancer progression. Glucosylceramide (GlcCer) is a ubiquitous glycosphingolipid (GSL) generated by glucosylceramide synthase, a key regulatory enzyme encoded by the UDP-glucose ceramide glucosyltransferase (UGCG) gene. Stressed cells increase de novo biosynthesis of ceramides, which return to sub-toxic levels after UGCG mediates incorporation into GlcCer. Given that cancer cells seem to mobilize UGCG and have increased GSL content for ceramide clearance, which ultimately contributes to chemotherapy failure, here we investigated how inhibition of GSL biosynthesis affects the MDR phenotype of chronic myeloid leukemias. We found that MDR is associated with higher UGCG expression and with a complex GSL profile. UGCG inhibition with the ceramide analog d-threo-1-(3,4,-ethylenedioxy)phenyl-2-palmitoylamino-3-pyrrolidino-1-propanol (EtDO-P4) greatly reduced GSL and monosialotetrahexosylganglioside levels, and co-treatment with standard chemotherapeutics sensitized cells to mitochondrial membrane potential loss and apoptosis. ABC subfamily B member 1 (ABCB1) expression was reduced, and ABCC-mediated efflux activity was modulated by competition with nonglycosylated ceramides. Consistently, inhibition of ABCC-mediated transport reduced the efflux of exogenous C6-ceramide. Overall, UGCG inhibition impaired the malignant glycophenotype of MDR leukemias, which typically overcomes drug resistance through distinct mechanisms. This work sheds light on the involvement of GSL in chemotherapy failure, and its findings suggest that targeted GSL modulation could help manage MDR leukemias.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Glicoesfingolipídeos/sangue , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Proteínas de Neoplasias/metabolismo , Transportadores de Cassetes de Ligação de ATP/genética , Glucosiltransferases/antagonistas & inibidores , Glucosiltransferases/genética , Glucosiltransferases/metabolismo , Glicoesfingolipídeos/genética , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Proteínas de Neoplasias/genética , Propanolaminas/farmacologia , Pirrolidinas/farmacologia
10.
Blood Rev ; 43: 100671, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32107072

RESUMO

Chronic myeloid leukemia (CML) is a myeloproliferative disorder characterized by the BCR-ABL oncoprotein, known to drive leukemogenesis by orchestrating multiple signaling pathways ultimately involved in cell survival. Despite successful response rates of CML patients to tyrosine kinase inhibitors (TKIs), resistance eventually arises due to BCR-ABL-dependent and independent mechanisms. Survivin is an inhibitor of apoptosis protein acting in the interface between apoptosis deregulation and cell cycle progression. In CML, high levels of survivin have been associated with late stages of disease and therapy resistance. In this review, we provide an overview of important aspects concerning survivin subcellular localization and expression pattern in CML patients and cell lines. Moreover, we highlight the relevance of molecular networks involving survivin for disease progression and treatment resistance. Finally, we discuss the mechanisms accounting for survivin overexpression, as well as novel therapeutic interventions that have been designed to counteract survivin-associated malignancy in CML.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Survivina/genética , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Terapia de Alvo Molecular , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Survivina/análise , Regulação para Cima/efeitos dos fármacos
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