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1.
Clin Immunol ; 245: 109142, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36182049

RESUMO

Autoimmune thyroid disease has been described as a complication of HSCT for different indications and as a manifestation of inborn errors of immunity, like SCID. A 1-month female was diagnosed with RAG1-mutated SCID and received allogenic HSCT. She developed autoimmune hypothyroidism 5 months after transplantation and was treated with levo-thyroxine with a good response. Autoimmune thyroid disease can develop after HSCT during the immune reconstitution phase, leading to potentially severe neurological and growth impairment, particularly in SCID patients, often transplanted during the first year of life. Recommendations regarding early and frequent vigilance for thyroid function are needed in these patients.


Assuntos
Doença de Hashimoto , Transplante de Células-Tronco Hematopoéticas , Imunodeficiência Combinada Severa , Feminino , Humanos , Encéfalo , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Imunodeficiência Combinada Severa/diagnóstico , Imunodeficiência Combinada Severa/terapia , Tireotropina , Recém-Nascido
2.
Bone Marrow Transplant ; 52(1): 7-14, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27348539

RESUMO

Advances in biological techniques have potentiated great progresses in understanding the interaction between human beings and the ∼10 to 100 trillion microbes living in their gastrointestinal tract: gut microbiota (GM). In this review, we describe recent emerging data on the role of GM in hematopoietic stem cell transplantation, with a focus on immunomodulatory properties in the immune system recovery and the impact in the development of the main complications, as GvHD and infections.


Assuntos
Microbioma Gastrointestinal/imunologia , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Imunomodulação , Infecções , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/microbiologia , Humanos , Infecções/imunologia , Infecções/microbiologia
5.
Leukemia ; 31(1): 18-25, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27416911

RESUMO

Recurrent molecular markers have been routinely used in acute myeloid leukemia (AML) for risk assessment at diagnosis, whereas their post-induction monitoring still represents a debated issue. We evaluated the prognostic value and biological impact of minimal residual disease (MRD) and of the allelic ratio (AR) of FLT3-internal-tandem duplication (ITD) in childhood AML. We retrospectively screened 494 children with de novo AML for FLT3-ITD mutation, identifying 54 harboring the mutation; 51% of them presented high ITD-AR at diagnosis and had worse event-free survival (EFS, 19.2 versus 63.5% for low ITD-AR, <0.05). Forty-one percent of children with high levels of MRD after the 1st induction course, measured by a patient-specific real-time-PCR, had worse EFS (22.2 versus 59.4% in low-MRD patients, P<0.05). Next, we correlated these parameters with gene expression, showing that patients with high ITD-AR or persistent MRD had characteristic expression profiles with deregulated genes involved in methylation and acetylation. Moreover, patients with high CyclinA1 expression presented an unfavorable EFS (20.3 versus 51.2% in low CyclinA1 group, P<0.01). Our results suggest that ITD-AR levels and molecular MRD should be considered in planning clinical management of FLT3-ITD patients. Different transcriptional activation of epigenetic and oncogenic profiles may explain variability in outcome among these patients, for whom novel therapeutic approaches are desirable.


Assuntos
Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Tirosina Quinase 3 Semelhante a fms/genética , Criança , Pré-Escolar , Intervalo Livre de Doença , Epigênese Genética/genética , Regulação Leucêmica da Expressão Gênica , Humanos , Neoplasia Residual/genética , Prognóstico , Estudos Retrospectivos
6.
Transpl Infect Dis ; 18(1): 44-54, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26574232

RESUMO

BACKGROUND: In 28 pediatric allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients, we aimed to evaluate: (i) the impact of routine Epstein-Barr virus (EBV) DNA monitoring on the development of EBV-related post-transplant lymphoproliferative disorder (EBV-PTLD); (ii) the incidence of EBV infection and the potential risk factors; and (iii) the suitability of whole blood (WB) as clinical specimen to monitor the risk of patients to develop EBV-PTLD. METHODS: Quantitative real-time polymerase chain reaction assay was performed on WB samples for all patients. EBV DNA quantification also in peripheral blood mononuclear cells (PBMCs) samples was adopted for the patients at higher risk of developing EBV-PTLD (≥ 10,000 copies/mL WB). RESULTS: High EBV DNAemia levels were observed in 37.5% of the actively infected recipients (57.1%). Severe aplastic anemia, matched-unrelated donor transplant, the reduced-intensity conditioning regimen and, to a lesser extent, the in vivo T-cell depletion with anti-thymocyte immunoglobulin were associated with high viral load. A significant correlation between EBV DNA levels in WB and PBMC samples was obtained (r = 0.755, P < 0.001). A similar kinetics of EBV DNA in the 2 blood compartments was observed. Clinically, both specimen types appeared to be equally informative to assess the risk of patients to develop PTLD. On the basis of EBV DNAemia levels, in 3 patients (10.7%) immunosuppressive therapy was reduced and 1 patient (3.5%) received early treatment for probable EBV disease. No patients developed EBV-PTLD. CONCLUSION: WB proved to be a suitable clinical specimen to monitor EBV DNA load after allo-HSCT for the management of EBV infection and PTLD prevention.


Assuntos
Infecções por Vírus Epstein-Barr/prevenção & controle , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Herpesvirus Humano 4/isolamento & purificação , Transtornos Linfoproliferativos/prevenção & controle , Adolescente , Criança , Pré-Escolar , DNA Viral/sangue , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/tratamento farmacológico , Infecções por Vírus Epstein-Barr/virologia , Feminino , Herpesvirus Humano 4/genética , Humanos , Terapia de Imunossupressão , Lactente , Itália , Leucócitos Mononucleares/virologia , Transtornos Linfoproliferativos/etiologia , Transtornos Linfoproliferativos/terapia , Masculino , Pediatria , Complicações Pós-Operatórias , Estudos Prospectivos , Carga Viral
7.
Bone Marrow Transplant ; 50(7): 992-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25893458

RESUMO

Acute GvHD (aGvHD) is the main complication of hematopoietic SCT (HSCT) during the treatment of hematological disorders. We carried out the first longitudinal study to follow the gut microbiota trajectory, from both the phylogenetic and functional points of view, in pediatric patients undergoing HSCT. Gut microbiota trajectories and short-chain fatty acid production profiles were followed starting from before HSCT and through the 3-4 months after transplant in children developing and not developing aGvHD. According to our findings, HSCT procedures temporarily cause a structural and functional disruption of the gut microbial ecosystem, describing a trajectory of recovery during the following 100 days. The onset of aGvHD is associated with specific gut microbiota signatures both along the course of gut microbiota reconstruction immediately after transplant and, most interestingly, prior to HSCT. Indeed, in pre-HSCT samples, non-aGvHD patients showed higher abundances of propionate-producing Bacteroidetes, highly adaptable microbiome mutualists that showed to persist during the HSCT-induced ecosystem disruption. Our data indicate that structure and temporal dynamics of the gut microbial ecosystem can be a relevant factor for the success of HSCT and opens the perspective to the manipulation of the pre-HSCT gut microbiota configuration to favor mutualistic persisters with immunomodulatory properties in the gut.


Assuntos
Microbioma Gastrointestinal/fisiologia , Doença Enxerto-Hospedeiro/complicações , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante Homólogo/efeitos adversos , Doença Aguda , Criança , Feminino , Humanos , Estudos Longitudinais
8.
Bone Marrow Transplant ; 50(2): 181-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25387094

RESUMO

We analyzed the outcome of 243 children with high-risk (HR) AML in first CR1 enrolled in the AIEOP-2002/01 protocol, who were given either allogeneic (ALLO; n=141) or autologous (AUTO; n=102) hematopoietic SCT (HSCT), depending on the availability of a HLA-compatible sibling. Infants, patients with AML-M7, or complex karyotype or those with FLT3-ITD, were eligible to be transplanted also from alternative donors. All patients received a myeloablative regimen combining busulfan, cyclophosphamide and melphalan; [corrected] AUTO-HSCT patients received BM cells in most cases, while in children given ALLO-HSCT stem cell source was BM in 96, peripheral blood in 19 and cord blood in 26. With a median follow-up of 57 months (range 12-130), the probability of disease-free survival (DFS) was 73% and 63% in patients given either ALLO- or AUTO-HSCT, respectively (P=NS). Although the cumulative incidence (CI) of relapse was lower in ALLO- than in AUTO-HSCT recipients (17% vs 28%, respectively; P=0.043), the CI of TRM was 7% in both groups. Patients transplanted with unrelated donor cord blood had a remarkable 92.3% 8-year DFS probability. Altogether, these data confirm that HSCT is a suitable option for preventing leukemia recurrence in HR children with CR1 AML.


Assuntos
Transplante de Células-Tronco de Sangue do Cordão Umbilical , Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/terapia , Agonistas Mieloablativos/administração & dosagem , Condicionamento Pré-Transplante/métodos , Cariótipo Anormal , Adolescente , Aloenxertos , Autoenxertos , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Lactente , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Masculino , Taxa de Sobrevida , Tirosina Quinase 3 Semelhante a fms/genética
9.
Br J Nutr ; 112(11): 1751-68, 2014 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-25325563

RESUMO

Hepatitis B virus (HBV) infection represents a serious global health problem and persistent HBV infection is associated with an increased risk of cirrhosis, hepatocellular carcinoma and liver failure. Recently, the study of the role of microRNA (miRNA) in the pathogenesis of HBV has gained considerable interest as well as new treatments against this pathogen have been approved. A few studies have investigated the antiviral activity of vitamin E (VE) in chronic HBV carriers. Herein, we review the possible role of tocopherols in the modulation of host miRNA with potential anti-HBV activity. A systematic research of the scientific literature was performed by searching the MEDLINE, Cochrane Library and EMBASE databases. The keywords used were 'HBV therapy', 'HBV treatment', 'VE antiviral effects', 'tocopherol antiviral activity', 'miRNA antiviral activity' and 'VE microRNA'. Reports describing the role of miRNA in the regulation of HBV life cycle, in vitro and in vivo available studies reporting the effects of VE on miRNA expression profiles and epigenetic networks, and clinical trials reporting the use of VE in patients with HBV-related chronic hepatitis were identified and examined. Based on the clinical results obtained in VE-treated chronic HBV carriers, we provide a reliable hypothesis for the possible role of this vitamin in the modulation of host miRNA profiles perturbed by this viral pathogen and in the regulation of some cellular miRNA with a suggested potential anti-HBV activity. This approach may contribute to the improvement of our understanding of pathogenetic mechanisms involved in HBV infection and increase the possibility of its management and treatment.


Assuntos
Antivirais/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , MicroRNAs/metabolismo , Tocoferóis/uso terapêutico , Genoma Viral , Vírus da Hepatite B/efeitos dos fármacos , Vírus da Hepatite B/genética , Vírus da Hepatite B/fisiologia , Hepatite B Crônica/genética , Hepatite B Crônica/virologia , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Interações Hospedeiro-Patógeno/genética , Humanos , MicroRNAs/genética , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Replicação Viral/efeitos dos fármacos
12.
Eur J Paediatr Dent ; 15(1): 45-50, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24745592

RESUMO

AIM: To investigate with a reliable method the oral features in Italian patients in remission from cancer, highlighting the relationship with age at cancer therapy and to compare the data with healthy controls. MATERIALS AND METHODS: Twenty five childhood cancer survivors treated under the age of 10 years with chemotherapy w/wo Haemopoietic Stem Cell Transplantation and/or head-neck Radiotherapy, in remission from cancer for at least 3 years, were examined for dental caries and enamel defects. To assess dental age and dental abnormalities a panoramic radiograph was taken. Patients were grouped according to age at cancer therapy (<3 years: subgroup Y; 3.1-5 years: subgroup M; >5 years: subgroup O). A control group of 26 healthy children was included. RESULTS: There was not a statistically significant difference in caries prevalence between the two groups. A statistically significant difference between the two groups was found for enamel defects, dental abnormalities and dental age. The chi-squared test revealed a relationship between age at therapy and specific dental abnormalities. CONCLUSION: This study shows that cancer therapy may increase the risk of development of enamel defects and dental abnormalities, especially in children treated under the age of 3 years.


Assuntos
Neoplasias de Cabeça e Pescoço/terapia , Terapia Neoadjuvante , Sobreviventes , Doenças Dentárias/etiologia , Adolescente , Determinação da Idade pelos Dentes , Fatores Etários , Anodontia/etiologia , Antineoplásicos/uso terapêutico , Estudos de Casos e Controles , Criança , Índice CPO , Cárie Dentária/etiologia , Esmalte Dentário/anormalidades , Feminino , Seguimentos , Neoplasias de Cabeça e Pescoço/radioterapia , Transplante de Células-Tronco Hematopoéticas , Humanos , Itália , Masculino , Odontogênese/fisiologia , Saúde Bucal , Projetos Piloto , Radiografia Panorâmica , Anormalidades Dentárias/etiologia , Raiz Dentária/anormalidades , Adulto Jovem
13.
Leukemia ; 28(3): 543-53, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24253024

RESUMO

Constitutively active casein kinase 2 (CK2) signaling is a common feature of T-cell acute lymphoblastic leukemia (T-ALL). CK2 phosphorylates PTEN (phosphatase and tensin homolog) tumor suppressor, resulting in PTEN stabilization and functional inactivation. Downregulation of PTEN activity has an impact on PI3K/Akt/mTOR signaling, which is of fundamental importance for T-ALL cell survival. These observations lend compelling weight to the application of CK2 inhibitors in the therapy of T-ALL. Here, we have analyzed the therapeutic potential of CX-4945-a novel, highly specific, orally available, ATP-competitive inhibitor of CK2α. We show that CX-4945 treatment induced apoptosis in T-ALL cell lines and patient T lymphoblasts. CX-4945 downregulated PI3K/Akt/mTOR signaling in leukemic cells. Notably, CX-4945 affected the unfolded protein response (UPR), as demonstrated by a significant decrease in the levels of the main UPR regulator GRP78/BIP, and led to apoptosis via upregulation of the ER stress/UPR cell death mediators IRE1α and CHOP. In vivo administration of CX-4945 to a subcutaneous xenotransplant model of human T-ALL significantly delayed tumor growth. Our findings indicate that modulation of the ER stress/UPR signaling through CK2 inhibition could be exploited for inducing apoptosis in T-ALL cells and that CX-4945 may be an efficient treatment for those T-ALLs displaying upregulation of CK2α/PI3K/Akt/mTOR signaling.


Assuntos
Antineoplásicos/uso terapêutico , Caseína Quinase II/antagonistas & inibidores , Naftiridinas/uso terapêutico , Proteínas de Neoplasias/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Transdução de Sinais , Resposta a Proteínas não Dobradas , Animais , Divisão Celular , Chaperona BiP do Retículo Endoplasmático , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Proteínas de Neoplasias/química , Fenazinas , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia
14.
Leukemia ; 28(6): 1196-206, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24310736

RESUMO

Constitutively active phosphoinositide 3-kinase (PI3K) signaling is a common feature of T-cell acute lymphoblastic leukemia (T-ALL), where it upregulates cell proliferation, survival and drug resistance. These observations lend compelling weight to the application of PI3K inhibitors in the therapy of T-ALL. Here, we have analyzed the therapeutic potential of the pan-PI3K inhibitor NVP-BKM120 (BKM120), an orally bioavailable 2,6-dimorpholino pyrimidine derivative, which has entered clinical trials for solid tumors, on both T-ALL cell lines and patient samples. BKM120 treatment resulted in G2/M phase cell cycle arrest and apoptosis, being cytotoxic to a panel of T-ALL cell lines and patient T lymphoblasts, and promoting a dose- and time-dependent dephosphorylation of Akt and S6RP. BKM120 maintained its pro-apoptotic activity against Jurkat cells even when cocultured with MS-5 stromal cells, which mimic the bone marrow microenvironment. Remarkably, BKM120 synergized with chemotherapeutic agents currently used for treating T-ALL patients. Moreover, in vivo administration of BKM120 to a subcutaneous xenotransplant model of human T-ALL significantly delayed tumor growth, thus prolonging survival time. Taken together, our findings indicate that BKM120, either alone or in combination with chemotherapeutic drugs, may be an efficient treatment for T-ALLs that have aberrant upregulation of the PI3K signaling pathway.


Assuntos
Aminopiridinas/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Morfolinas/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase , Leucemia-Linfoma Linfoblástico de Células T Precursoras/tratamento farmacológico , Animais , Western Blotting , Citometria de Fluxo , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
16.
J Pediatr Gastroenterol Nutr ; 56(2): 151-5, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22922376

RESUMO

BACKGROUND: Benign nodular hepatic regenerating lesions such as focal nodular hyperplasia (FNH) have been reported as rare complications of the antineoplastic therapy received during infancy. Little is known about the risk factors associated with the onset of these lesions and their diagnostic management. METHODS: We have analyzed a series of benign hepatic nodular lesions occurring in children previously treated for malignant tumors in our institution in a period of 11 years. An extensive description of the imaging presentation of the lesions has been provided to facilitate the differential diagnosis, and a risk factor analysis has been conducted. RESULTS: A total of 14 diagnoses (10 FNH and 4 hemangiomas) of benign nodular hepatic lesions have been found. Hematopoietic stem cell transplantation is the most important statistically independent risk factor associated with the development of these lesions, especially for FNH. No malignant transformation of nodules has been recorded during a median follow-up time of 4 years. CONCLUSIONS: In our experience, FNH is the most frequent benign nodular hepatic lesions occurring after treatment for childhood cancer. Hematopoietic stem cell transplantation is the most important risk factor to be taken in account. After a secure diagnosis of these benign lesions, only a close imaging follow-up is recommended.


Assuntos
Hiperplasia Nodular Focal do Fígado/etiologia , Hemangioma/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Fígado/patologia , Neoplasias , Adolescente , Adulto , Criança , Diagnóstico Diferencial , Feminino , Hiperplasia Nodular Focal do Fígado/epidemiologia , Hiperplasia Nodular Focal do Fígado/patologia , Hemangioma/epidemiologia , Hemangioma/patologia , Humanos , Incidência , Masculino , Neoplasias/complicações , Neoplasias/terapia , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
17.
J Biol Regul Homeost Agents ; 27(4): 935-46, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24382174

RESUMO

Primary immunodeficiencies (PIDs) are rare diseases characterized by an increased susceptibility to infections. Early diagnosis and appropriate treatment are critical for reducing morbidity and mortality. Based on available data, the efficacy of antibiotic administration for the prophylaxis of infections remains uncertain, and recommendations supporting this practice are poor. The use of antimicrobial prophylaxis is mainly based on single institution-specific experience without controlled measurements of patient safety and quality health outcomes. To address this issue an Italian Network on Primary Immunodeficiencies (IPINet) has been set up in 1999 within the Italian Association of Pediatric Hematology and Oncology (AIEOP) to increase the awareness of these disorders among physicians. Further, diagnostic and treatment guideline recommendations have been established to standardize the best clinical assistance to all patients, including antibiotic prophylaxis, and for a national epidemiologic monitoring of PIDs. The aim of this review is not only to give a scientific update on the use of antimicrobial prophylaxis in selected congenital immunological disorders but also to draw a picture of this practice in the context of the Italian Primary Immunodeficiency Network (IPINet). Controlled multicenter studies are necessary to establish if, when and how you should start an efficacious antimicrobial prophylaxis.


Assuntos
Antibioticoprofilaxia , Síndromes de Imunodeficiência/complicações , Imunodeficiência de Variável Comum/complicações , Síndrome de DiGeorge/complicações , Doença Granulomatosa Crônica/complicações , Humanos , Deficiência de IgA/complicações , Doenças por Imunodeficiência Combinada Ligada ao Cromossomo X/complicações
18.
Leukemia ; 26(11): 2336-42, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22614243

RESUMO

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive neoplastic disorder arising from T-cell progenitors. T-ALL accounts for 15% of newly diagnosed ALL cases in children and 25% in adults. Although the prognosis of T-ALL has improved, due to the use of polychemotherapy schemes, the outcome of relapsed/chemoresistant T-ALL cases is still poor. A signaling pathway that is frequently upregulated in T-ALL, is the phosphatidylinositol 3-kinase/Akt/mTOR network. To explore whether Akt could represent a target for therapeutic intervention in T-ALL, we evaluated the effects of the novel allosteric Akt inhibitor, MK-2206, on a panel of human T-ALL cell lines and primary cells from T-ALL patients. MK-2206 decreased T-ALL cell line viability by blocking leukemic cells in the G(0)/G(1) phase of the cell cycle and inducing apoptosis. MK-2206 also induced autophagy, as demonstrated by an increase in the 14-kDa form of LC3A/B. Western blotting analysis documented a concentration-dependent dephosphorylation of Akt and its downstream targets, GSK-3α/ß and FOXO3A, in response to MK-2206. MK-2206 was cytotoxic to primary T-ALL cells and induced apoptosis in a T-ALL patient cell subset (CD34(+)/CD4(-)/CD7(-)), which is enriched in leukemia-initiating cells. Taken together, our findings indicate that Akt inhibition may represent a potential therapeutic strategy in T-ALL.


Assuntos
Compostos Heterocíclicos com 3 Anéis/farmacologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Western Blotting , Ciclo Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Sinergismo Farmacológico , Humanos , Fosforilação , Leucemia-Linfoma Linfoblástico de Células T Precursoras/enzimologia , Transdução de Sinais
19.
Leukemia ; 26(1): 91-100, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21968881

RESUMO

The mammalian target of rapamycin (mTOR) serine/threonine kinase is the catalytic subunit of two multi-protein complexes, referred to as mTORC1 and mTORC2. Signaling downstream of mTORC1 has a critical role in leukemic cell biology by controlling mRNA translation of genes involved in both cell survival and proliferation. mTORC1 activity can be downmodulated by upregulating the liver kinase B1/AMP-activated protein kinase (LKB1/AMPK) pathway. Here, we have explored the therapeutic potential of the anti-diabetic drug, metformin (an LKB1/AMPK activator), against both T-cell acute lymphoblastic leukemia (T-ALL) cell lines and primary samples from T-ALL patients displaying mTORC1 activation. Metformin affected T-ALL cell viability by inducing autophagy and apoptosis. However, it was much less toxic against proliferating CD4(+) T-lymphocytes from healthy donors. Western blot analysis demonstrated dephosphorylation of mTORC1 downstream targets. Unlike rapamycin, we found a marked inhibition of mRNA translation in T-ALL cells treated with metformin. Remarkably, metformin targeted the side population of T-ALL cell lines as well as a putative leukemia-initiating cell subpopulation (CD34(+)/CD7(-)/CD4(-)) in patient samples. In conclusion, metformin displayed a remarkable anti-leukemic activity, which emphasizes future development of LKB1/AMPK activators as clinical candidates for therapy in T-ALL.


Assuntos
Adenilato Quinase/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Proteínas/metabolismo , Transdução de Sinais , Apoptose , Sequência de Bases , Linhagem Celular Tumoral , Primers do DNA , Citometria de Fluxo , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina , Metformina/farmacologia , Complexos Multiproteicos , Fosforilação , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Biossíntese de Proteínas/efeitos dos fármacos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Serina-Treonina Quinases TOR
20.
Dev Dyn ; 240(11): 2482-94, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22012593

RESUMO

The establishment of rat embryonic stem cells constitutes a precious tool since rat has been extensively used in biomedical research, in particular for the generation of human neurodisease animal models. Up to now only a few studies have described the isolation of rat embryonic stem-like cells. One out of 9 isolated rat embryonic stem-like cell lines (B1-RESC) obtained from a 4.5-day post-coitum blastocyst were extensively characterized and kept in culture for up to 80 passages on feeders with LIF. The stable growth of these cells and the expression of pluripotent markers were confirmed up to a high number of passages in culture, also in the absence of feeders and LIF. B1-RESC expresses the three germ layers markers both in vitro, within differentiating embryoid bodies, and in vivo through teratoma formation. Collectively, the B1-RESC line with a stable near-diploid karyotype can be used as a highly sensitive tool for testing anti-proliferative molecules.


Assuntos
Descoberta de Drogas/métodos , Células-Tronco Embrionárias/citologia , Pesquisa com Células-Tronco , Animais , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Separação Celular/métodos , Células Cultivadas , Células-Tronco Embrionárias/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Camundongos , Modelos Biológicos , Gravidez , Ratos , Ratos Sprague-Dawley
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