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1.
Am J Hosp Palliat Care ; 40(7): 761-764, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36205034

RESUMO

Although hematologic neoplasms have been on the vanguard of cancer therapies that led to notable advances in therapeutic efficacy, many patients face significant symptom burden, which make them eligible for early palliative care (PC) integration. However, previous reports demonstrated that hematological malignancies receive more aggressive care at the end-of-life and are less likely to receive care from specialist palliative services compared to solid tumors. Our aim was to characterize symptom burden, performance status and clinical characteristics of a cohort of hematologic malignancies patients referred to PC outpatient consultation, according to their diagnosis. Fifty-nine hematological malignancies patients referred to PC consultation between January 2018 and September 2021 were included. Clinical and laboratory data were evaluated retrospectively by medical charts analysis. Patients exhibited high ESAS and reduced PPS scores at the time of PC referral. Acute leukemia and multiple myeloma patients had the highest symptom burden scores; in spite of this, median time from the first PC consultation until death was only 3 and 4 months, respectively. In conclusion, we identified that hematologic neoplasms patients are highly symptomatic and are frequently referred to PC in end stages of their disease.


Assuntos
Neoplasias Hematológicas , Mieloma Múltiplo , Neoplasias , Humanos , Estudos Retrospectivos , Neoplasias Hematológicas/terapia , Neoplasias/terapia , Cuidados Paliativos , Encaminhamento e Consulta , Mieloma Múltiplo/terapia
3.
Molecules ; 26(19)2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34641325

RESUMO

Flavonoids are ubiquitous groups of polyphenolic compounds present in most natural products and plants. These substances have been shown to have promising chemopreventive and chemotherapeutic properties with multiple target interactions and multiple pathway regulations against various human cancers. Polyphenolic flavonoid compounds can block the initiation or reverse the promotion stage of multistep carcinogenesis. Quercetin is one of the most abundant flavonoids found in fruits and vegetables and has been shown to have multiple properties capable of reducing cell growth in cancer cells. Acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) therapy remains a challenge for hematologists worldwide, and the outcomes for patients with both disorders continue to be poor. This scenario indicates the increasing demand for innovative drugs and rational combinative therapies. Herein, we discuss the multitarget effects of the flavonoid quercetin, a naturally occurring flavonol, on AML and MDS.


Assuntos
Leucemia Mieloide Aguda/tratamento farmacológico , Síndromes Mielodisplásicas/tratamento farmacológico , Quercetina/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Leucemia Mieloide Aguda/metabolismo , Síndromes Mielodisplásicas/metabolismo , Quercetina/química , Quercetina/farmacologia , Espécies Reativas de Oxigênio
4.
Integr Cancer Ther ; 20: 15347354211002647, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33754891

RESUMO

Green tea (GT) treatment was evaluated for its effect on the immune and antineoplastic response of elderly acute myeloid leukemia patients with myelodysplasia-related changes (AML-MRC) who are ineligible for aggressive chemotherapy and bone marrow transplants. The eligible patients enrolled in the study (n = 10) received oral doses of GT extract (1000 mg/day) alone or combined with low-dose cytarabine chemotherapy for at least 6 months and/or until progression. Bone marrow (BM) and peripheral blood (PB) were evaluated monthly. Median survival was increased as compared to the control cohort, though not statistically different. Interestingly, improvements in the immunological profile of patients were found. After 30 days, an activated and cytotoxic phenotype was detected: GT increased total and naïve/effector CD8+ T cells, perforin+/granzyme B+ natural killer cells, monocytes, and classical monocytes with increased reactive oxygen species (ROS) production. A reduction in the immunosuppressive profile was also observed: GT reduced TGF-ß and IL-4 expression, and decreased regulatory T cell and CXCR4+ regulatory T cell frequencies. ROS levels and CXCR4 expression were reduced in bone marrow CD34+ cells, as well as nuclear factor erythroid 2-related factor 2 (NRF2) and hypoxia-inducible factor 1α (HIF-1α) expression in biopsies. Immune modulation induced by GT appears to occur, regardless of tumor burden, as soon as 30 days after intake and is maintained for up to 180 days, even in the presence of low-dose chemotherapy. This pilot study highlights that GT extracts are safe and could improve the immune system of elderly AML-MRC patients.


Assuntos
Leucemia Mieloide Aguda , Chá , Idoso , Linfócitos T CD8-Positivos , Citarabina , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Projetos Piloto
5.
Invest New Drugs ; 39(3): 736-746, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33403501

RESUMO

Chronic myeloid leukemia (CML) is successfully treated with BCR-ABL1 tyrosine kinase inhibitors, but a significant percentage of patients develop resistance. Insulin receptor substrate 1 (IRS1) has been shown to constitutively associate with BCR-ABL1, and IRS1-specific silencing leads to antineoplastic effects in CML cell lines. Here, we characterized the efficacy of NT157, a pharmacological inhibitor of IGF1R-IRS1/2, in CML cells and observed significantly reduced cell viability and proliferation, accompanied by induction of apoptosis. In human K562 cells and in murine Ba/F3 cells, engineered to express either wild-type BCR-ABL1 or the imatinib-resistant BCR-ABL1T315I mutant, NT157 inhibited BCR-ABL1, IGF1R, IRS1/2, PI3K/AKT/mTOR, and STAT3/5 signaling, increased CDKN1A, FOS and JUN tumor suppressor gene expression, and reduced MYC and BCL2 oncogenes. NT157 significantly reduced colony formation of human primary CML cells with minimal effect on normal hematopoietic cells. Exposure of primary CML cells harboring BCR-ABL1T315I to NT157 resulted in increased apoptosis, reduced cell proliferation and decreased phospho-CRKL levels. In conclusion, NT157 has antineoplastic effects on BCR-ABL1 leukemogenesis, independent of T315I mutational status.


Assuntos
Antineoplásicos/uso terapêutico , Proteínas Substratos do Receptor de Insulina/antagonistas & inibidores , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Pirogalol/análogos & derivados , Receptor IGF Tipo 1/antagonistas & inibidores , Sulfonamidas/uso terapêutico , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Regulação Neoplásica da Expressão Gênica , Humanos , Mesilato de Imatinib/farmacologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Camundongos , Inibidores de Proteínas Quinases/farmacologia , Pirogalol/farmacologia , Pirogalol/uso terapêutico , Sulfonamidas/farmacologia
6.
Blood Cells Mol Dis ; 84: 102460, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32562952

RESUMO

ANKHD1 is highly expressed in various cancers such as leukemia and multiple myeloma. Silencing of ANKHD1 expression leads to decreased cell proliferation and accumulation of cells at the S phase. In this study we found ANKHD1 expression to be higher at the S phase, suggesting it to be an S phase protein. We observed that ANKHD1 interacts with histone promoter regions and its inhibition downregulates expression of all core histones, implying a role in histone synthesis. Since histone synthesis occurs in parallel with DNA replication at S phase, we evaluated PCNA (Proliferating Cell Nuclear Antigen) expression, a protein involved in DNA replication and repair. PCNA expression was found to be significantly decreased in ANKHD1 silenced cells. We further observed accumulation γH2AX, a marker for DNA double stranded breaks and an early sign of DNA damage induced by replication stress, upon ANKHD1 silencing. The expressions of several genes implicated in DNA repair were also modulated in ANKHD1 silenced cells, confirming the role of ANKHD1 in DNA repair. Based on this study we speculate that ANKHD1 is an S phase protein required for histone synthesis and DNA repair. These results however, are preliminary and require thorough investigation.


Assuntos
Reparo do DNA , Histonas/metabolismo , Mieloma Múltiplo/metabolismo , Proteínas de Ligação a RNA/metabolismo , Linhagem Celular Tumoral , Replicação do DNA , Regulação Neoplásica da Expressão Gênica , Humanos , Mieloma Múltiplo/genética , Proteínas de Ligação a RNA/genética , Fase S
7.
J Cell Mol Med ; 23(4): 3021-3025, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30770626

RESUMO

LEF1 antisense RNA 1 (LEF1-AS1) is an antisense long non-coding RNA encoded in the lymphoid enhancer-binding factor 1 (LEF1) locus. LEF1-AS1 is a conserved transcript dysregulated in hematopoiesis. This study aimed to functionally characterize the role of this transcript in myeloid malignancy and explore a possible regulatory effect of LEF1-AS1 upon LEF1. We show that LEF1-AS1 is highly expressed in normal hematopoietic stem cells but barely detectable in myeloid malignant cell lines. Additionally, bone marrow cells from myelodysplastic syndrome (n=12) and acute myeloid malignancy patients (n=28) expressed significantly reduced levels of LEF1-AS1 compared to healthy controls (n=15). Artificial LEF1-AS1 over-expression inhibited proliferation in HL60 and led to an upregulation of tumor suppressors p21 and p27, and reduced ERK1/2 activation. Unexpectedly, no underlying modulation of LEF1 was detected. Ectopic expression of LEF1-AS1 also inhibited proliferation in HELA, a cell line lacking endogenous expression of LEF1, supporting a LEF1-independent mechanism. Additionally, transient over-expression of LEF1-AS1 in AML patient cells also led to reduced proliferation and colony formation capacity. We used a mass spectrometry-based proteomics approach. Proteomic quantification identified the modulation of an important metabolic regulator, Fumarase, and concomitant accumulation of the metabolite fumarate.


Assuntos
Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Leucemia Mieloide Aguda/patologia , Fator 1 de Ligação ao Facilitador Linfoide/metabolismo , Síndromes Mielodisplásicas/patologia , RNA Longo não Codificante/genética , Estudos de Casos e Controles , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Fator 1 de Ligação ao Facilitador Linfoide/genética , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/metabolismo , Prognóstico , Taxa de Sobrevida , Células Tumorais Cultivadas
8.
Vox Sang ; 114(2): 178-181, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30695814

RESUMO

Disturbances in the physiological regulation of erythropoietin (EPO) in patients with sickle cell disease (SCD) may contribute to worsening anaemia and increased transfusion requirements, but the use of recombinant EPO in this group of patients is controversial. The objective of this study was to evaluate the use of this drug in adult patients with SCD and its effects on haemoglobin levels and transfusion requirements. We conducted a retrospective analysis at the University of Campinas, with nineteen adults with a diagnosis of SCD (HbSS and HbS/ß+ thalassaemia), who had received at least 1 year of EPO therapy between 2007 and 2014. Haemoglobin concentrations and trends of variation in transfused RBC volumes were compared before and after EPO administration. We observed that seven patients had a good response to treatment (Hb increment higher than 1·5 g/dl) and nine had a partial response (0·5-1·5 g/dl increment) and there was a significant decrease in the need for transfusion amongst those who usually required regular transfusions. There were no increases in the rates of vaso-occlusive crisis or venous thromboembolism in comparison to the year before the onset of the therapy. Erythropoietin therapy led to a marked increase in haemoglobin concentration with a concomitant decrease in the demand for transfusion. Considering all complications related to allogeneic transfusion, we believe that EPO therapy represents an important therapeutic tool in sickle cell anaemia.


Assuntos
Anemia Falciforme/tratamento farmacológico , Eritropoetina/uso terapêutico , Adulto , Anemia Falciforme/terapia , Transfusão de Eritrócitos/efeitos adversos , Eritropoetina/administração & dosagem , Feminino , Hemoglobinas/análise , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/uso terapêutico
9.
Oncogenesis ; 7(10): 82, 2018 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-30310057

RESUMO

DNA methyltransferase inhibitor (DNMTi) treatments have been used for patients with myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML), and have shown promising beneficial effects in some other types of cancers. Here, we demonstrate that the transcriptional repressor ZBTB38 is a critical regulator of the cellular response to DNMTi. Treatments with 5-azacytidine, or its derivatives decitabine and zebularine, lead to down-regulation of ZBTB38 protein expression in cancer cells, in parallel with cellular damage. The depletion of ZBTB38 by RNA interference enhances the toxicity of DNMTi in cell lines from leukemia and from various solid tumor types. Further we observed that inactivation of ZBTB38 causes the up-regulation of CDKN1C mRNA, a previously described indirect target of DNMTi. We show that CDKN1C is a key actor of DNMTi toxicity in cells lacking ZBTB38. Finally, in patients with MDS a high level of CDKN1C mRNA expression before treatment correlates with a better clinical response to a drug regimen combining 5-azacytidine and histone deacetylase inhibitors. Collectively, our results suggest that the ZBTB38 protein is a target of DNMTi and that its depletion potentiates the toxicity of DNMT inhibitors in cancer cells, providing new opportunities to enhance the response to DNMT inhibitor therapies in patients with MDS and other cancers.

10.
Hemoglobin ; 40(3): 150-5, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27117565

RESUMO

In this study, we describe four new patients with sickle cell disease who had limb amputations. Two of the patients had sickle cell anemia [Hb S (HBB: c.20A > T) (ß(S)/ß(S))] with refractory leg ulcers that required amputations. The third patient had sickle cell trait with an extensive leg ulcer that was associated with epidermoid carcinoma. The fourth patient had amputations of both forearms and feet due to a misdiagnosis of dactylitis. Review of the literature showed that the indications for amputations in sickle cell disease included three distinct categories: mythical beliefs, therapeutic and malpractice. All therapeutic amputations were for severely painful, large, recalcitrant leg ulcers that failed non-interventional therapies. Amputation resulted in pain relief and better quality of life. Phantom neuropathic pain was not a major issue post-operatively. It was absent, transient or well controlled with antidepressants. Limb function was restored post-amputation with prosthetic artificial limbs, wheelchairs or crutches. Malpractice amputations were due to misdiagnosis or to cryotherapy by exposing the painful limb to ice water resulting in thrombosis, gangrene and amputation. We strongly suggest that leg amputations should be considered in the management of certain patients with severe extensive refractory leg ulcers, and topical cryotherapy should never be used to manage sickle cell pain.


Assuntos
Amputação Cirúrgica , Anemia Falciforme/cirurgia , Úlcera da Perna/cirurgia , Qualidade de Vida , Anemia Falciforme/complicações , Anemia Falciforme/terapia , Tomada de Decisões , Erros de Diagnóstico , Humanos , Úlcera da Perna/etiologia , Imperícia , Manejo da Dor
11.
Oncotarget ; 7(6): 6948-59, 2016 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-26755644

RESUMO

The recurrent V617F mutation in JAK2 (JAK2V617F) has emerged as the primary contributor to the pathogenesis of myeloproliferative neoplasms (MPN). However, the lack of complete response in most patients treated with the JAK1/2 inhibitor, ruxolitinib, indicates the need for identifying pathways that cooperate with JAK2. Activated JAK2 was found to be associated with the insulin receptor substrate 2 (IRS2) in non-hematological cells. We identified JAK2/IRS2 binding in JAK2V617F HEL cells, but not in the JAK2WT U937 cell line. In HEL cells, IRS2 silencing decreased STAT5 phosphorylation, reduced cell viability and increased apoptosis; these effects were enhanced when IRS2 silencing was combined with ruxolitinib. In U937 cells, IRS2 silencing neither reduced cell viability nor induced apoptosis. IRS1/2 pharmacological inhibition in primary MPN samples reduced cell viability in JAK2V617F-positive but not JAK2WT specimens; combination with ruxolitinib had additive effects. IRS2 expression was significantly higher in CD34+ cells from essential thrombocythemia patients compared to healthy donors, and in JAK2V617F MPN patients when compared to JAK2WT. Our data indicate that IRS2 is a binding partner of JAK2V617F in MPN. IRS2 contributes to increased cell viability and reduced apoptosis in JAK2-mutated cells. Combined pharmacological inhibition of IRS2 and JAK2 may have a potential clinical application in MPN.


Assuntos
Apoptose/efeitos dos fármacos , Proteínas Substratos do Receptor de Insulina/antagonistas & inibidores , Janus Quinase 2/genética , Mutação/genética , Transtornos Mieloproliferativos/patologia , Pirazóis/farmacologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Estudos de Casos e Controles , Proliferação de Células/efeitos dos fármacos , Feminino , Imunofluorescência , Seguimentos , Inativação Gênica , Humanos , Técnicas Imunoenzimáticas , Imunoprecipitação , Proteínas Substratos do Receptor de Insulina/genética , Proteínas Substratos do Receptor de Insulina/metabolismo , Janus Quinase 2/metabolismo , Masculino , Pessoa de Meia-Idade , Transtornos Mieloproliferativos/tratamento farmacológico , Transtornos Mieloproliferativos/genética , Estadiamento de Neoplasias , Nitrilas , Prognóstico , Pirimidinas , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto , Adulto Jovem
13.
Haematologica ; 100(6): 730-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25769545

RESUMO

As hypoxia-induced inflammatory angiogenesis may contribute to the manifestations of sickle cell disease, we compared the angiogenic molecular profiles of plasma from sickle cell disease individuals and correlated these with in vitro endothelial cell-mediated angiogenesis-stimulating activity and in vivo neovascularization. Bioplex demonstrated that plasma from patients with steady-state sickle cell anemia contained elevated concentrations of pro-angiogenic factors (angiopoietin-1, basic fibroblast growth factor, vascular endothelial growth factor, vascular endothelial growth factor-D and placental growth factor) and displayed potent pro-angiogenic activity, significantly increasing endothelial cell proliferation, migration and capillary-like structure formation. In vivo neovascularization of Matrigel plugs was significantly greater in sickle cell disease mice than in non-sickle cell disease mice, consistent with an up-regulation of angiogenesis in the disease. In plasma from patients with hemoglobin SC disease without proliferative retinopathy, anti-angiogenic endostatin and thrombospondin-2 were significantly elevated. In contrast, plasma from hemoglobin SC individuals with proliferative retinopathy had a pro-angiogenic profile and more significant effects on endothelial cell proliferation and capillary formation than plasma from patients without retinopathy. Hydroxyurea therapy was associated with significant reductions in plasma angiogenic factors and inhibition of endothelial cell-mediated angiogenic mechanisms and neovascularization. Thus, individuals with sickle cell anemia or hemoglobin SC disease with retinopathy present a highly angiogenic circulating milieu, capable of stimulating key endothelial cell-mediated angiogenic mechanisms. Combination anti-angiogenic therapy to prevent the progression of unregulated neovascularization and associated manifestations in sickle cell disease, such as pulmonary hypertension, may be indicated; furthermore, the benefits and drawbacks of the potent anti-angiogenic effects of hydroxyurea should be clarified.


Assuntos
Anemia Falciforme/sangue , Anemia Falciforme/tratamento farmacológico , Antidrepanocíticos/farmacologia , Células Endoteliais/metabolismo , Hidroxiureia/farmacologia , Neovascularização Patológica/sangue , Adolescente , Adulto , Animais , Antidrepanocíticos/uso terapêutico , Células Endoteliais/efeitos dos fármacos , Feminino , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Hidroxiureia/uso terapêutico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Pessoa de Meia-Idade , Neovascularização Patológica/tratamento farmacológico , Adulto Jovem
14.
Haematologica ; 100(4): 466-71, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25596272

RESUMO

Hemoglobin SC disease is a very prevalent hemoglobinopathy; however, very little is known about this condition specifically. There appears to be an increased risk of thromboembolic events in hemoglobin SC disease, but studies evaluating the hemostatic alterations are lacking. We describe the findings of a cross-sectional observational study evaluating coagulation activation markers in adult patients with hemoglobin SC, comparing them with those in sickle cell anemia patients and healthy controls. A total of 56 hemoglobin SC and 39 sickle cell anemia patients were included in the study, all in steady state, and 27 healthy controls. None of the patients was taking hydroxyurea. Hemoglobin SC patients had a significantly up-regulated relative expression of tissue factor, as well as elevations in thrombin-antithrombin complex and D-dimer, in comparison to controls (P<0.01). Hemoglobin SC patients had lower tissue factor expression, and thrombin-antithrombin complex and D-dimer levels when compared to sickle cell anemia patients (P<0.05). Markers of endothelial activation (soluble thrombomodulin and soluble vascular cell adhesion molecule-1) and inflammation (tumor necrosis factor-alpha) were both significantly elevated in hemoglobin SC patients when compared to controls, being as high as the levels seen in patients with sickle cell anemia. Overall, in hemoglobin SC patients, higher hemolytic activity and inflammation were associated with a more intense activation of coagulation, and hemostatic activation was associated with two very prevalent chronic complications seen in hemoglobin SC disease: retinopathy and osteonecrosis. In summary, our results demonstrate that hemoglobin SC patients have a hypercoagulable state, although this manifestation was not as intense as that seen in sickle cell anemia.


Assuntos
Coagulação Sanguínea , Doença da Hemoglobina SC/sangue , Trombofilia/sangue , Adulto , Biomarcadores/sangue , Estudos Transversais , Células Endoteliais/metabolismo , Feminino , Expressão Gênica , Doença da Hemoglobina SC/complicações , Doença da Hemoglobina SC/diagnóstico , Doença da Hemoglobina SC/genética , Hemólise , Humanos , Mediadores da Inflamação , Leucócitos/metabolismo , Masculino , Pessoa de Meia-Idade , Tromboplastina/genética
15.
Biochim Biophys Acta ; 1853(2): 388-95, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25450971

RESUMO

Vasodilator-stimulated phosphoprotein (VASP) and Zyxin are interacting proteins involved in cellular adhesion and motility. PKA phosphorylates VASP at serine 157, regulating VASP cellular functions. VASP interacts with ABL and is a substrate of the BCR-ABL oncoprotein. The presence of BCR-ABL protein drives oncogenesis in patients with chronic myeloid leukemia (CML) due to a constitutive activation of tyrosine kinase activity. However, the function of VASP and Zyxin in BCR-ABL pathway and the role of VASP in CML cells remain unknown. In vitro experiments using K562 cells showed the involvement of VASP in BCR-ABL signaling. VASP and Zyxin inhibition decreased the expression of anti-apoptotic proteins, BCL2 and BCL-XL. Imatinib induced an increase in phosphorylation at Ser157 of VASP and decreased VASP and BCR-ABL interaction. VASP did not interact with Zyxin in K562 cells; however, after Imatinib treatment, this interaction was restored. Corroborating our data, we demonstrated the absence of phosphorylation at Ser157 in VASP in the bone marrow of CML patients, in contrast to healthy donors. Phosphorylation of VASP on Ser157 was restored in Imatinib responsive patients though not in the resistant patients. Therefore, we herein identified a possible role of VASP in CML pathogenesis, through the regulation of BCR-ABL effector proteins or the absence of phosphorylation at Ser157 in VASP.


Assuntos
Benzamidas/farmacologia , Moléculas de Adesão Celular/metabolismo , Proteínas de Fusão bcr-abl/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Proteínas dos Microfilamentos/metabolismo , Fosfoproteínas/metabolismo , Piperazinas/farmacologia , Pirimidinas/farmacologia , Zixina/metabolismo , Apoptose/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Células da Medula Óssea/patologia , Proliferação de Células/efeitos dos fármacos , Células Clonais , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Técnicas de Silenciamento de Genes , Inativação Gênica/efeitos dos fármacos , Humanos , Mesilato de Imatinib , Células K562 , Fosforilação/efeitos dos fármacos , Fosfosserina/metabolismo , Ligação Proteica/efeitos dos fármacos , Proteína bcl-X/metabolismo
16.
Leuk Res ; 38(10): 1245-51, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25139846

RESUMO

Mastocytosis are myeloproliferative neoplasms commonly related to gain-of-function mutations involving the tyrosine kinase domain of KIT. We herein report a case of familial systemic mastocytosis with the rare KIT K509I germ line mutation affecting two family members: mother and daughter. In vitro treatment with imatinib, dasatinib and PKC412 reduced cell viability of primary mast cells harboring KIT K509I mutation. However, imatinib was more effective in inducing apoptosis of neoplastic mast cells. Both patients with familial systemic mastocytosis had remarkable hematological and skin improvement after three months of imatinib treatment, suggesting that it may be an effective front line therapy for patients harboring KIT K509I mutation.


Assuntos
Mutação em Linhagem Germinativa , Mastocitose Sistêmica/tratamento farmacológico , Mastocitose Sistêmica/genética , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-kit/genética , Adulto , Apoptose/efeitos dos fármacos , Sequência de Bases , Benzamidas/farmacologia , Western Blotting , Dasatinibe , Feminino , Humanos , Mesilato de Imatinib , Piperazinas/farmacologia , Pirimidinas/farmacologia , Estaurosporina/análogos & derivados , Estaurosporina/farmacologia , Tiazóis/farmacologia , Adulto Jovem
17.
PLoS One ; 9(2): e89012, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24551209

RESUMO

Sickle cell anemia (SCA) is associated with a hypercoagulable state. Increased platelet activation is reported in SCA and SCA platelets may present augmented adhesion to the vascular endothelium, potentially contributing to the vaso-occlusive process. We sought to observe the effects of platelets (PLTs) from healthy control (CON) individuals and SCA individuals on endothelial activation, in vitro. Human umbilical vein endothelial cells (HUVEC) were cultured, in the presence, or not, of washed PLTs from CON or steady-state SCA individuals. Supernatants were reserved for cytokine quantification, and endothelial adhesion molecules (EAM) were analyzed by flow cytometry; gene expressions of ICAM1 and genes of the NF-κB pathway were analyzed by qPCR. SCA PLTs were found to be more inflammatory, displaying increased adhesive properties, an increased production of IL-1ß and a tendency towards elevated expressions of P-selectin and activated αIIbß3. Following culture in the presence of SCA PLTs, HUVEC presented significant augmentations in the expressions of the EAM, ICAM-1 and E-selectin, as well as increased IL-8 production and increased ICAM1 and NFKB1 (encodes p50 subunit of NF-κB) gene expressions. Interestingly, transwell inserts abolished the effects of SCA PLTs on EAM expression. Furthermore, an inhibitor of the NF-κB pathway, BAY 11-7082, also prevented the induction of EAM expression on the HUVEC surface by SCA PLTs. In conclusion, we find further evidence to indicate that platelets circulate in an activated state in sickle cell disease and are capable of stimulating endothelial cell activation. This effect appears to be mediated by direct contact, or even adhesion, between the platelets and endothelial cells and via NFκB-dependent signaling. As such, activated platelets in SCD may contribute to endothelial activation and, therefore, to the vaso-occlusive process. Results provide further evidence to support the use of anti-platelet approaches in association with other therapies for SCD.


Assuntos
Anemia Falciforme/genética , Plaquetas/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Transdução de Sinais/genética , Adolescente , Adulto , Anemia Falciforme/metabolismo , Anemia Falciforme/patologia , Plaquetas/patologia , Adesão Celular , Técnicas de Cocultura , Selectina E/genética , Selectina E/metabolismo , Feminino , Regulação da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-1beta/biossíntese , Interleucina-1beta/metabolismo , Interleucina-8/biossíntese , Interleucina-8/metabolismo , Masculino , Pessoa de Meia-Idade , NF-kappa B/antagonistas & inibidores , NF-kappa B/genética , NF-kappa B/metabolismo , Nitrilas/farmacologia , Selectina-P/genética , Selectina-P/metabolismo , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/genética , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Cultura Primária de Células , Sulfonas/farmacologia
18.
FEBS Lett ; 586(24): 4311-8, 2012 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-23142581

RESUMO

ANKHD1 is a multiple ankyrin repeat containing protein, highly expressed in cancers, such as acute leukemia. The present study was undertaken to determine the expression and functional significance of ANKHD1 in human Multiple Myeloma (MM). We found that ANKHD1 is highly expressed in MM patient cells and cell lines. In vitro, lentiviral mediated ANKHD1-shRNA inhibited proliferation and delayed S to G2M cell cycle progression in glucocorticoid resistant (U266) and sensitive (MM1S) MM cells. Further ANKHD1 silencing resulted in upregulation of cyclin dependent kinase inhibitor p21 irrespective of the p53 status of the MM cell lines. These data suggest that ANKHD1 might have a role in MM cell proliferation and cell cycle progression by regulating expression of p21.


Assuntos
Ciclo Celular , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Mieloma Múltiplo/metabolismo , Proteínas de Ligação a RNA/biossíntese , Linhagem Celular Tumoral , Inativação Gênica , Glucocorticoides/uso terapêutico , Humanos , Mieloma Múltiplo/genética , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Proteínas de Ligação a RNA/genética , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima
19.
PLoS One ; 7(8): e43090, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22905207

RESUMO

We hypothesized that analysis of single nucleotide polymorphism arrays (SNP-A) and new molecular defects may provide new insight in the pathogenesis of systemic mastocytosis (SM). SNP-A karyotyping was applied to identify recurrent areas of loss of heterozygosity and bidirectional sequencing was performed to evaluate the mutational status of TET2, DNMT3A, ASXL1, EZH2, IDH1/IDH2 and the CBL gene family. Overall survival (OS) was analyzed using the Kaplan-Meier method. We studied a total of 26 patients with SM. In 67% of SM patients, SNP-A karyotyping showed new chromosomal abnormalities including uniparental disomy of 4q and 2p spanning TET2/KIT and DNMT3A. Mutations in TET2, DNMT3A, ASXL1 and CBL were found in 23%, 12%, 12%, and 4% of SM patients, respectively. No mutations were observed in EZH2 and IDH1/IDH2. Significant differences in OS were observed for SM mutated patients grouped based on the presence of combined TET2/DNMT3A/ASXL1 mutations independent of KIT (P = 0.04) and sole TET2 mutations (P<0.001). In conclusion, TET2, DNMT3A and ASXL1 mutations are also present in mastocytosis and these mutations may affect prognosis, as demonstrated by worse OS in mutated patients.


Assuntos
DNA (Citosina-5-)-Metiltransferases/genética , Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica , Mastocitose Sistêmica/genética , Polimorfismo de Nucleotídeo Único , Proteínas Proto-Oncogênicas c-cbl/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Repressoras/genética , Adolescente , Adulto , Idoso , DNA Metiltransferase 3A , Análise Mutacional de DNA , Primers do DNA/genética , Dioxigenases , Feminino , Predisposição Genética para Doença , Humanos , Cariotipagem , Pessoa de Meia-Idade , Mutação , Prognóstico
20.
Biochim Biophys Acta ; 1813(8): 1404-11, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21569802

RESUMO

BCR-ABL kinase activates downstream signaling pathways, including the PI3K-Akt/mTOR and the MAPK pathway. IRS1 has been previously described as constitutively phosphorylated and associated with BCR-ABL in K562 cells, suggesting that IRS1 has role in the BCR-ABL signaling pathways. In this study, we analyzed the effect of IRS1 silencing, by shRNA-lentiviral delivery, in K562 cells, a CML cell line that presents the BCR-ABL. IRS1 silencing decreased cell proliferation and colony formation in K562 cells, which correlates with the delay of these cells at the G0/G1 phase and a decrease in the S phase of the cell cycle. Furthermore, IRS1 silencing in K562 cells resulted in a decrease of Akt, P70S6K and ERK1/2 phosphorylation. Nevertheless, apoptosis was unaffected by IRS1 knockdown and no alterations were found in the phosphorylation of BAD and in the expression of BCL2 and BAX. BCR-ABL and CRKL phosphorylation levels remained unaffected upon IRS1 silencing, and no synergistic effect was observed with imatinib treatment and IRS1 knockdown, indicating that IRS1 is downstream from BCR-ABL. In conclusion, we demonstrated that inhibition of IRS1 is capable of inducing the downregulation of Akt/mTOR and MAPK pathways and further decreasing proliferation, and clonogenicity and induces to cell cycle delay at G0/G1 phase in BCR-ABL cells.


Assuntos
Proteínas Substratos do Receptor de Insulina/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Apoptose , Sequência de Bases , Caspase 3/metabolismo , Ciclo Celular , Proliferação de Células , Ensaio de Unidades Formadoras de Colônias , Primers do DNA/genética , Regulação para Baixo , Proteínas de Fusão bcr-abl/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Proteínas Substratos do Receptor de Insulina/genética , Proteínas Substratos do Receptor de Insulina/metabolismo , Células K562 , Sistema de Sinalização das MAP Quinases , Proteínas Nucleares/metabolismo , Fosforilação , RNA Interferente Pequeno/genética , Transdução de Sinais
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