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1.
J Cell Mol Med ; 2021 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-34132464

RESUMEN

Patients with relapsed/refractory acute myeloid leukaemia (AML), ineligible for intensive chemotherapy and allogeneic stem cell transplantation, have a dismal prognosis. For such cases, hypomethylating agents are a viable alternative, but with limited success. Combination chemotherapy using a hypomethylating agent plus another drug would potentially bring forward new alternatives. In the present manuscript, we present the cell and molecular background for a clinical scenario of a 44-year-old patient, diagnosed with high-grade serous ovarian carcinoma, diagnosed, and treated with a synchronous AML. Once the ovarian carcinoma relapsed, maintenance treatment with olaparib was initiated. Concomitantly, the bone marrow aspirate showed 30% myeloid blasts, consistent with a relapse of the underlying haematological disease. Azacytidine 75 mg/m2 treatment was started for seven days. The patient was administered two regimens of azacytidine monotherapy, additional to the olaparib-based maintenance therapy. After the second treatment, the patient presented with leucocytosis and 94% myeloid blasts on the bone marrow smear. Later, the patient unfortunately died. Following this clinical scenario, we reproduced in vitro the combination chemotherapy of azacytidine plus olaparib, to accurately assess the basic mechanisms of leukaemia progression, and resistance to treatment. Combination chemotherapy with drugs that theoretically target both malignancies might potentially be of use. Still, further research, both pre-clinical and clinical, is needed to accurately assess such cases.

2.
J Cell Mol Med ; 24(19): 11100-11110, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32889753

RESUMEN

Primary myelofibrosis (PMF) is a Ph-negative myeloproliferative neoplasm (MPN), characterized by advanced bone marrow fibrosis and extramedullary haematopoiesis. The bone marrow fibrosis results from excessive proliferation of fibroblasts that are influenced by several cytokines in the microenvironment, of which transforming growth factor-ß (TGF-ß) is the most important. Micromechanics related to the niche has not yet been elucidated. In this study, we hypothesized that mechanical stress modulates TGF-ß signalling leading to further activation and subsequent proliferation and invasion of bone marrow fibroblasts, thus showing the important role of micromechanics in the development and progression of PMF, both in the bone marrow and in extramedullary sites. Using three PMF-derived fibroblast cell lines and transforming growth factor-ß receptor (TGFBR) 1 and 2 knock-down PMF-derived fibroblasts, we showed that mechanical stress does stimulate the collagen synthesis by the fibroblasts in patients with myelofibrosis, through the TGFBR1, which however seems to be activated through alternative pathways, other than TGFBR2.


Asunto(s)
Progresión de la Enfermedad , Mielofibrosis Primaria/metabolismo , Mielofibrosis Primaria/fisiopatología , Factor de Crecimiento Transformador beta/metabolismo , Animales , Fenómenos Biomecánicos , Fibroblastos/metabolismo , Fibroblastos/patología , Humanos , Hipertensión Pulmonar/complicaciones , Hipertensión Pulmonar/diagnóstico por imagen , Ratones Desnudos , Modelos Biológicos , Mielofibrosis Primaria/complicaciones , Mielofibrosis Primaria/patología , Receptor Tipo I de Factor de Crecimiento Transformador beta/metabolismo , Receptor Tipo II de Factor de Crecimiento Transformador beta/metabolismo , Estrés Mecánico
3.
J Cell Physiol ; 233(1): 422-433, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28294327

RESUMEN

Although the cause for bone marrow fibrosis in patients with myelofibrosis remains controversial, it has been hypothesized that it is caused by extensive fibroblast proliferation under the influence of cytokines generated by the malignant megakaryocytes. Moreover, there is no known drug therapy which could reverse the process. We studied the fibroblasts in a novel system using the hanging drop method, evaluated whether the fibroblasts obtain from patients are part of the malignant clone of not and, using this system, we screen a large library of FDA-approved drugs to identify potential drugs candidates that might be useful in the treatment of this disease, specifically which would inhibit fibroblast proliferation and the development of bone marrow fibrosis. We have found that the BM fibroblasts are not part of the malignant clone, as previously suspected and two immunosuppressive medications-cyclosporine and mycophenolate mophetil, as most potent suppressors of the fibroblast collagen production thus potentially inhibitors of bone marrow fibrosis production in myelofibrosis.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Colágeno/metabolismo , Ciclosporina/farmacología , Descubrimiento de Drogas/instrumentación , Fibroblastos/efectos de los fármacos , Ensayos Analíticos de Alto Rendimiento , Ácido Micofenólico/farmacología , Mielofibrosis Primaria/tratamiento farmacológico , Línea Celular , Relación Dosis-Respuesta a Droga , Fibroblastos/metabolismo , Fibroblastos/patología , Fibrosis , Regulación de la Expresión Génica , Janus Quinasa 2/genética , Janus Quinasa 2/metabolismo , Cinética , Mutación , Mielofibrosis Primaria/genética , Mielofibrosis Primaria/metabolismo , Mielofibrosis Primaria/patología , Factor de Crecimiento Transformador beta/farmacología
4.
Crit Rev Clin Lab Sci ; 55(7): 501-515, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30238808

RESUMEN

Even if considered a cumulative and not a proliferative CD5+ B-cell neoplasm, chronic lymphocytic leukemia (CLL) has a proliferation rate higher than that recognized earlier, especially in the lymphoid tissues. Some patients with CLL develop a clinical syndrome entitled Richter syndrome (RS). Understanding CLL genetics and epigenetics may help to elucidate the molecular basics of the clinical heterogeneity of this type of malignancy. In the present project we aimed to identify a microRNA species that can predict the evolution of therapy-resistant CLL towards RS. In the first phase of our study, microRNA-19b was identified as a possible target, and in the second phase, we transfected three different CLL cell lines with microRNA-19b mimic and inhibitor and assessed the potential role on leukemia cells in vitro. The mechanism by which miR-19b acts were identified as the upregulation of Ki67 and downregulation of p53. This was further supported through RT-PCR and western blotting on CLL cell lines, as well as by next generation sequencing on two patients diagnosed with CLL that evolved into RS.


Asunto(s)
Transformación Celular Neoplásica , Exosomas , Leucemia Linfocítica Crónica de Células B , MicroARNs , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Exosomas/química , Exosomas/metabolismo , Femenino , Humanos , Leucemia Linfocítica Crónica de Células B/sangre , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/metabolismo , Leucemia Linfocítica Crónica de Células B/patología , Masculino , MicroARNs/sangre , MicroARNs/genética , MicroARNs/metabolismo , Persona de Mediana Edad , Pronóstico , Síndrome , Células Tumorales Cultivadas
5.
J BUON ; 20(2): 361-75, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26011324

RESUMEN

Liver malignancies represent one of the major public health problems worldwide because of late diagnosis and failure of current treatments to offer a curative option for many of the patients. MicroRNAs (miRs) are small non-coding RNA molecules that are known to regulate the gene expression at a post-transcriptional level through complementary base pairing with thousands of messenger (m)RNAs. Recent data has shown the involvement of miRs in the pathogenesis of many human cancers, including those of the liver, with huge possible impact in the clinic, mainly due to the identification of non-coding RNAs as biomarkers that can often be detected in the systemic circulation. In the current review, we present the importance of miRs in liver cancers by discussing their role in the pathobiology of these diseases, apart from their role as diagnostic and prognostic markers for liver malignancies.


Asunto(s)
Neoplasias Hepáticas/genética , MicroARNs/fisiología , Biomarcadores de Tumor/sangre , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/terapia , MicroARNs/sangre , Transcriptoma
6.
Cell Stem Cell ; 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38917807

RESUMEN

Clonal hematopoiesis (CH) arises when hematopoietic stem cells (HSCs) acquire mutations, most frequently in the DNMT3A and TET2 genes, conferring a competitive advantage through mechanisms that remain unclear. To gain insight into how CH mutations enable gradual clonal expansion, we used single-cell multi-omics with high-fidelity genotyping on human CH bone marrow (BM) samples. Most of the selective advantage of mutant cells occurs within HSCs. DNMT3A- and TET2-mutant clones expand further in early progenitors, while TET2 mutations accelerate myeloid maturation in a dose-dependent manner. Unexpectedly, both mutant and non-mutant HSCs from CH samples are enriched for inflammatory and aging transcriptomic signatures, compared with HSCs from non-CH samples, revealing a non-cell-autonomous effect. However, DNMT3A- and TET2-mutant HSCs have an attenuated inflammatory response relative to wild-type HSCs within the same sample. Our data support a model whereby CH clones are gradually selected because they are resistant to the deleterious impact of inflammation and aging.

7.
J Clin Med ; 10(20)2021 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-34682889

RESUMEN

INTRODUCTION: The examination of vital signs and their changes during illness can alert physicians to possible impending deterioration and organ dysfunction. The Modified Early Warning Score (MEWS) is used worldwide as a track and trigger system that can help to identify patients at risk of critical illness. Thus, the current study aimed to assess the ability of MEWS to predict the mortality of hematologic patients at the point of transfer from the ward to the intensive care unit (ICU). MATERIALS AND METHODS: The present study was retrospective, longitudinal, and observational, conducted at an oncology hospital in the city of Cluj-Napoca, Romania. We included 174 patients with hematological disorders transferred from the ward to the ICU between the 1st of January 2018 and the 1st of May 2020. We assessed the MEWS at the moment of admission in these patients in the ICU. The accuracy of MEWS in predicting mortality was assessed via the area under the receiver operating characteristic curves (AUC), and sensitivity, specificity, and hazard ratio (HR) were calculated for different MEWS cutoffs. MEWS values considering the status at discharge and frequency of death by MEWS were also analyzed. RESULTS: We calculated MEWS values considering the status at discharge (p < 0.0001), and we assessed the frequency of death by MEWS. We also calculated the hazard ratio (HR) of death depending on the selected MEWS cutoff. The best cutoff point was found to be ≥6, with an accuracy of 0.667, sensitivity of 0.675, specificity of 0.646, and AUC of 0.731. Patients with higher MEWS had a higher probability of mortality. CONCLUSION: The MEWS and cutoff points were determined on a sample of hematologic patients at the moment of admission to the ICU. The final aim is to encourage physicians to use these scores to improve awareness of organ failure to admit patients to the ICU sooner and limit overall morbidity and mortality. The presence of an ICU physician on ward rounds might help in reducing the timeframe of access to a high-dependency unit (HDU) or ICU. An extension of these scores outside hematologic patients or considering hematologic patients outside ICU must be further studied.

8.
J Cancer Res Ther ; 13(3): 406-411, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28862200

RESUMEN

Prostate cancer, one of the most common male malignancies with an increasing incidence in the recent years, requires the development of new methods of treatment. One of the most debated subjects is the tumor-associated macrophages (TAM). Although, the pathophysiological mechanisms are still a subject of intense research, TAM acts as procarcinogenic factors. It was also demonstrated that hypoxia-inducible factor 1 (HIF1) induces the expression of TAM genes involved in prostate carcinogenesis. Furthermore, it should be noted that the stromal extracellular lactate, the result of tumoral glycolysis process is one of the HIF1 activators. In addition, lactate inhibits the differentiation of monocytes and dendritic cells and also induces the inactivation of the cytotoxic T-lymphocytes. Through an analysis of recent studies, we conclude that lactate is a vital component of several ways of modulating the immune response at the stromal prostatic adenocarcinoma including TAM activation and cytotoxic T lymphocytes immunosuppression. Our review focuses on the impact of lactate on prostatic adenocarcinoma progression in terms of its immunology, and how this influences the therapy of this condition and the clinical outcome.


Asunto(s)
Adenocarcinoma/metabolismo , Carcinogénesis/inmunología , Ácido Láctico/metabolismo , Neoplasias de la Próstata/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/inmunología , Adenocarcinoma/patología , Diferenciación Celular/genética , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Ácido Láctico/inmunología , Macrófagos/inmunología , Macrófagos/metabolismo , Macrófagos/patología , Masculino , Neoplasias de la Próstata/inmunología , Neoplasias de la Próstata/patología , Linfocitos T Citotóxicos/inmunología , Linfocitos T Citotóxicos/metabolismo , Linfocitos T Citotóxicos/patología
9.
Med Hypotheses ; 104: 30-34, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28673584

RESUMEN

Acute myeloid leukaemia (AML) is a malignancy in need of new therapeutic options. The current standard of care chemotherapy, leads to complete remission (CR) in the vast majority of adult patients under the age of 60. In contrast, CR rates in patients over the age of 60 reaches only 40-60%. While achievement of a CR is an important stepping stone in the treatment of AML, the majority of these patients experience relapse and die of their disease without adequate consolidation chemotherapy. Blood and marrow transplantation (BMT) can improve outcome in a select patient with AML but unfortunately, it is not a valid treatment option for the majority of older patients. Thus, the development of novel chemotherapy regimens that capitalizes on AML biology to eliminate the malignant clone with little to no side effects on the normal haematopoiesis is paramount in the treatment of elderly patients. In the current paper, we propose to take advantage of the dysfunctional DNA repair mechanisms present in AML cells and induce synthetic lethality using a combination of PARP inhibitors with low dose anthracycline and DNMT inhibitors. Such a combination, while effectively eliminating leukaemia should be well tolerated and thus, suitable for the treatment of frail patients.


Asunto(s)
Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Mutaciones Letales Sintéticas , Adulto , Anciano , Antraciclinas/farmacología , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Daño del ADN , Reparación del ADN , Supervivencia sin Enfermedad , Humanos , Persona de Mediana Edad , Modelos Teóricos , Recurrencia Local de Neoplasia , Inducción de Remisión
10.
Med Hypotheses ; 109: 42-45, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29150291

RESUMEN

Alopecia is a dermatological condition for which Janus kinase (JAK) inhibitors have recently emerged as potential therapy options, but with limited practical use because of the systemic side effects. The topical use of Ruxolitinib in alopecia universalis has been demonstrated, but little is known about the pharmacodynamics and pharmacokinetics of this way of administration. Nanomedicine provides improved therapeutics. In the current paper we present preliminary data regarding the potential use of Ruxolitinib-conjugated gold nanoparticles (GNPs) in dermatological conditions, as GNPs have been proven to have a reduced absorption rate into the systemic blood flow for cutaneous administration. Internalization of the newly formed bioconjugate was assessed by electron microscopy and the functional effects of the drug were investigated by cell counting, flow cytometry and western blotting. Our data show that gold nanoparticles conjugated with Ruxolitinib inhibit the proliferation of fibroblasts by inhibiting JAK2 protein. Ruxolitinib carried by gold nanoparticles alters the proliferation of human fibroblasts, which is of great clinical importance as it can be readily administered on the skin with minimal risk of systemic side effects.


Asunto(s)
Alopecia/tratamiento farmacológico , Oro/química , Nanopartículas del Metal/química , Pirazoles/farmacocinética , Administración Tópica , Animales , Dermatología , Humanos , Comunicación Interdisciplinaria , Lípidos/química , Microscopía Electrónica de Transmisión , Modelos Teóricos , Nitrilos , Porosidad , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/farmacocinética , Pirazoles/administración & dosificación , Pirimidinas , Piel/efectos de los fármacos , Absorción Cutánea
11.
Int J Nanomedicine ; 11: 641-60, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26929621

RESUMEN

BACKGROUND AND AIMS: Every year, in Europe, acute myeloid leukemia (AML) is diagnosed in thousands of adults. For most subtypes of AML, the backbone of treatment was introduced nearly 40 years ago as a combination of cytosine arabinoside with an anthracycline. This therapy is still the worldwide standard of care. Two-thirds of patients achieve complete remission, although most of them ultimately relapse. Since the FLT3 mutation is the most frequent, it serves as a key molecular target for tyrosine kinase inhibitors (TKIs) that inhibit FLT3 kinase. In this study, we report the conjugation of TKIs onto spherical gold nanoparticles. MATERIALS AND METHODS: The internalization of TKI-nanocarriers was proved by the strongly scattered light from gold nanoparticles and was correlated with the results obtained by transmission electron microscopy and dark-field microscopy. The therapeutic effect of the newly designed drugs was investigated by several methods including cell counting assay as well as the MTT assay. RESULTS: We report the newly described bioconjugates to be superior when compared with the drug alone, with data confirmed by state-of-the-art analyses of internalization, cell biology, gene analysis for FLT3-IDT gene, and Western blotting to assess degradation of the FLT3 protein. CONCLUSION: The effective transmembrane delivery and increased efficacy validate its use as a potential therapeutic.


Asunto(s)
Portadores de Fármacos , Sistemas de Liberación de Medicamentos , Oro/química , Leucemia Mieloide Aguda/tratamiento farmacológico , Nanopartículas del Metal/química , Inhibidores de Proteínas Quinasas/farmacología , Apoptosis/efectos de los fármacos , Western Blotting , Proliferación Celular/efectos de los fármacos , Oro/administración & dosificación , Humanos , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patología , Nanopartículas del Metal/administración & dosificación , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/química , ARN Mensajero/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas , Tirosina Quinasa 3 Similar a fms/antagonistas & inhibidores , Tirosina Quinasa 3 Similar a fms/genética , Tirosina Quinasa 3 Similar a fms/metabolismo
12.
J Gastrointestin Liver Dis ; 24(4): 435-43, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26697569

RESUMEN

BACKGROUND AND AIMS: Worldwide, colorectal cancer (CRC) is the third most common cancer in men and second in women. The aim of the current study was to identify whether the miR-375 is indeed down-regulated in metastatic CRC and if it could be considered as a potential minimally invasive prognostic biomarker for CRC. METHODS: Exosomes were isolated and characterized from patients with liver metastasis from CCR. The characterization of exosome was performed using TEM/SEM. HCT116 cells were treated with miR-375 mimic, NSM and miR-375 inhibitor. Functional assays included cell counting assay for 14 days, Matrigel invasion assay, apoptosis assay by flow cytometry using Annexin V-FITC, RT-PCR and Western blotting. RESULTS: Increased proliferation potential was proven for the cells transfected with miR-375 inhibitor, while the miR-375 mimic decreased the cell number. The cells transfected with the miR-375 inhibitor are aggressive and cross the membrane; 3.84% of the cells transfected with the miR-375 inhibitor entered apoptosis, while 6.45% of those transfected with the non-specific mimic were in programmed cell death, less than those transfected with the microRNA. RT-PCR for Bcl-2 expression showed that Bcl-2 is down-regulated for miR-375 inhibitor and up-regulated for the miR-375 mimic, a result confirmed by Western blotting. CONCLUSION: The present study brings to the forefront new data that suggest miR-375 as a new player in controlling the pathways responsible for inhibiting the natural history of CRC tumor cells, via the Bcl-2 pathway.


Asunto(s)
Neoplasias Colorrectales/metabolismo , Exosomas/metabolismo , Neoplasias Hepáticas/metabolismo , MicroARNs/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Apoptosis , Movimiento Celular , Proliferación Celular , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Exosomas/ultraestructura , Regulación Neoplásica de la Expresión Génica , Células HCT116 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/secundario , MicroARNs/genética , Proteínas Proto-Oncogénicas c-bcl-2/genética , Transducción de Señal , Factores de Tiempo , Transfección
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