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1.
Nat Commun ; 11(1): 4227, 2020 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-32839441

RESUMO

In hematopoietic cell transplants, alloreactive T cells mediate the graft-versus-leukemia (GVL) effect. However, leukemia relapse accounts for nearly half of deaths. Understanding GVL failure requires a system in which GVL-inducing T cells can be tracked. We used such a model wherein GVL is exclusively mediated by T cells that recognize the minor histocompatibility antigen H60. Here we report that GVL fails due to insufficient H60 presentation and T cell exhaustion. Leukemia-derived H60 is inefficiently cross-presented whereas direct T cell recognition of leukemia cells intensifies exhaustion. The anti-H60 response is augmented by H60-vaccination, an agonist αCD40 antibody (FGK45), and leukemia apoptosis. T cell exhaustion is marked by inhibitory molecule upregulation and the development of TOX+ and CD39-TCF-1+ cells. PD-1 blockade diminishes exhaustion and improves GVL, while blockade of Tim-3, TIGIT or LAG3 is ineffective. Of all interventions, FGK45 administration at the time of transplant is the most effective at improving memory and naïve T cell anti-H60 responses and GVL. Our studies define important causes of GVL failure and suggest strategies to overcome them.


Assuntos
Apresentação do Antígeno/imunologia , Efeito Enxerto vs Leucemia/imunologia , Transplante de Células-Tronco Hematopoéticas/métodos , Leucemia/terapia , Linfócitos T/imunologia , Animais , Células Cultivadas , Humanos , Leucemia/imunologia , Leucemia/patologia , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Antígenos de Histocompatibilidade Menor/genética , Antígenos de Histocompatibilidade Menor/imunologia , Antígenos de Histocompatibilidade Menor/metabolismo , Recidiva , Transplante Homólogo
3.
Adv Exp Med Biol ; 1207: 601-613, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32671778

RESUMO

Leukemia is a malignant clonal disease that originates from hematopoietic stem cells. As in-depth research examines the molecular biology and immunology of the hematopoietic system, leukemia treatment has evolved from a single cytotoxic drug to treatments that inducing differentiation and apoptosis. Meanwhile, autophagy has become a growing concern as a new form of cell death. The immune response, hematopoietic stem cell differentiation, and drug resistance of tumor cells are all potentially affected by autophagy. Regulating autophagy may become one of the promising directions in the field of targeted therapy.


Assuntos
Autofagia , Leucemia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Autofagia/efeitos dos fármacos , Células-Tronco Hematopoéticas/patologia , Humanos , Leucemia/tratamento farmacológico , Leucemia/patologia
4.
Anticancer Res ; 40(6): 3055-3063, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32487599

RESUMO

The idea of utilizing poly-ADP-ribose polymerase inhibitors (PARPi) as therapeutics for cancer has grown in popularity since its original approval for clinical usage in treatment of BRCA DNA repair-associated-mutated ovarian cancer. In this study, we evaluated experimental data regarding in vitro studies utilizing PARPi as a treatment for tyrosine kinase (TK)-dependent leukemia. Studies from 2015 to 2019 were compiled and the ones with most relevant TK pathways and PARP inhibition were analyzed. PARPi showed activity against many leukemia cell lines and samples from patients with primary leukemia, especially when combined with other signaling pathway inhibitor drugs, improving upon the hypothesis that the utilization of PARPi has potential as a new therapeutic approach in treatment of primary leukemia and TK-dependent leukemia.


Assuntos
Leucemia/tratamento farmacológico , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Humanos , Leucemia/patologia
5.
Cancer Treat Rev ; 88: 102026, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32592909

RESUMO

Progress in cancer therapy changed the outcome of many patients and moved therapy from chemotherapy agents to targeted drugs. Targeted drugs already changed the clinical practice in treatment of leukemias, such as imatinib (BCR/ABL inhibitor) in chronic myeloid leukemia (CML) and acute lymphoblastic leukemia (ALL), ibrutinib (Bruton's tyrosine kinase inhibitor) in chronic lymphocytic leukemia (CLL), venetoclax (BCL2 inhibitor) in CLL and acute myeloid leukemia (AML) or midostaurin (FLT3 inhibitor) in AML. In this review, we focused on DNA damage response (DDR) inhibition, specifically on inhibition of ATR-CHK1 pathway. Cancer cells harbor often defects in different DDR pathways, which render them vulnerable to DDR inhibition. Some DDR inhibitors showed interesting single-agent activity even in the absence of cytotoxic drug especially in cancers with underlying defects in DDR or DNA replication. Almost no mutations were found in ATR and CHEK1 genes in leukemia patients. Together with the fact that ATR-CHK1 pathway is essential for cell development and survival of leukemia cells, it represents a promising therapeutic target for treatment of leukemia. ATR-CHK1 inhibition showed excellent results in preclinical testing in acute and chronic leukemias. However, results in clinical trials are so far insufficient. Therefore, the ongoing and future clinical trials will decide on the success of ATR/CHK1 inhibitors in clinical practice of leukemia treatment.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Quinase 1 do Ponto de Checagem/metabolismo , Leucemia/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Doença Aguda , Animais , Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Quinase 1 do Ponto de Checagem/antagonistas & inibidores , Doença Crônica , Dano ao DNA , Humanos , Leucemia/genética , Leucemia/metabolismo , Leucemia/patologia , Terapia de Alvo Molecular , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Leuk Res ; 94: 106383, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32460059

RESUMO

Metformin is an anti-diabetic drug known to have anticancer activity by inhibiting mechanistic target of rapamycin (mTOR); however, other molecular mechanisms may also be involved. In this study, we examined the effects of metformin on the activity of receptor tyrosine kinases of the TAM (TYRO3, AXL, and MERTK) family, which have important roles in leukemia cell growth. The results indicated that metformin suppressed the in vitro growth of four leukemia cell lines, OCI/AML2, OCI/AML3, THP-1, and K562, in a dose-dependent manner, which corresponded to the downregulation of the expression and phosphorylation of AXL and inhibition of its downstream targets such as phosphorylation of STAT3. Furthermore, metformin augmented the suppressive effects of a small-molecule AXL inhibitor TP-0903 on the growth of OCI/AML3 and K562 cells and prevented doxorubicin-induced AXL activation in K562 cells, which induces chemoresistance in leukemia cells, thus potentiating doxorubicin anti-proliferative effects. Given that metformin also downregulated expression of TYRO3 and phosphorylation of MERTK, these findings indicate that anti-leukemic effects exerted by metformin could be partly due to the inhibition of TAM kinases. Thus, metformin has a clinical potential for patients with leukemia cells positive for AXL and the other TAM proteins as well as activated mTOR.


Assuntos
Regulação para Baixo/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Leucemia , Metformina/farmacologia , Proteínas Proto-Oncogênicas/biossíntese , Receptores Proteína Tirosina Quinases/biossíntese , Humanos , Células K562 , Leucemia/tratamento farmacológico , Leucemia/enzimologia , Leucemia/patologia , Células THP-1
7.
Ann Hematol ; 99(7): 1561-1564, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32451710

RESUMO

NUT midline carcinoma (NMC) is an aggressive neoplasm and mainly involved in the head and neck area. The defining genetic hallmark on these tumors is that testis-specific nuclear gene (NUTM1) fuses to bromodomain protein family member 4 gene (BRD4), resulting in the formation of BRD4-NUTM1 transcript. Here, we report a case with myeloid neoplasm complicating with eosinophilia (MLN-Eo) and rearrangement of PDGFRA, which co-exists with a new nucleosome assemble protein 1-like 4 gene (NAP1L4) NAP1L4-NUTM1 fusion. The patient have unusually clinical features and therapeutic reaction to imatinib mesylate. The cloned NAP1L4-NUTM1 gene structure is also determined.


Assuntos
Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 15/genética , Eosinofilia/genética , Transtornos Mieloproliferativos/tratamento farmacológico , Transtornos Mieloproliferativos/genética , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Adulto , Eosinofilia/complicações , Eosinofilia/tratamento farmacológico , Humanos , Síndrome Hipereosinofílica/genética , Síndrome Hipereosinofílica/patologia , Síndrome Hipereosinofílica/terapia , Mesilato de Imatinib/uso terapêutico , Leucemia/genética , Leucemia/patologia , Leucemia/terapia , Masculino , Mutação , Transtornos Mieloproliferativos/complicações , Transtornos Mieloproliferativos/patologia , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/isolamento & purificação , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/genética , Indução de Remissão , Translocação Genética/fisiologia
8.
Nat Commun ; 11(1): 2369, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32398749

RESUMO

Despite growing awareness of the biologic features underlying MLL-rearranged leukemia, targeted therapies for this leukemia have remained elusive and clinical outcomes remain dismal. MBNL1, a protein involved in alternative splicing, is consistently overexpressed in MLL-rearranged leukemias. We found that MBNL1 loss significantly impairs propagation of murine and human MLL-rearranged leukemia in vitro and in vivo. Through transcriptomic profiling of our experimental systems, we show that in leukemic cells, MBNL1 regulates alternative splicing (predominantly intron exclusion) of several genes including those essential for MLL-rearranged leukemogenesis, such as DOT1L and SETD1A. We finally show that selective leukemic cell death is achievable with a small molecule inhibitor of MBNL1. These findings provide the basis for a new therapeutic target in MLL-rearranged leukemia and act as further validation of a burgeoning paradigm in targeted therapy, namely the disruption of cancer-specific splicing programs through the targeting of selectively essential RNA binding proteins.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Regulação Neoplásica da Expressão Gênica , Leucemia/genética , Proteína de Leucina Linfoide-Mieloide/genética , Proteínas de Fusão Oncogênica/genética , Proteínas de Ligação a RNA/metabolismo , Processamento Alternativo , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Apoptose/genética , Transplante de Medula Óssea , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Conjuntos de Dados como Assunto , Técnicas de Silenciamento de Genes , Rearranjo Gênico , Histona-Lisina N-Metiltransferase/genética , Humanos , Íntrons/genética , Leucemia/tratamento farmacológico , Leucemia/patologia , Camundongos , Camundongos Knockout , Cultura Primária de Células , RNA Interferente Pequeno/metabolismo , Proteínas de Ligação a RNA/antagonistas & inibidores , Proteínas de Ligação a RNA/genética , RNA-Seq , Quimeras de Transplante , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Nat Commun ; 11(1): 2026, 2020 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-32332729

RESUMO

The cell-context dependency for RNA binding proteins (RBPs) mediated control of stem cell fate remains to be defined. Here we adapt the HyperTRIBE method using an RBP fused to a Drosophila RNA editing enzyme (ADAR) to globally map the mRNA targets of the RBP MSI2 in mammalian adult normal and malignant stem cells. We reveal a unique MUSASHI-2 (MSI2) mRNA binding network in hematopoietic stem cells that changes during transition to multipotent progenitors. Additionally, we discover a significant increase in RNA binding activity of MSI2 in leukemic stem cells compared with normal hematopoietic stem and progenitor cells, resulting in selective regulation of MSI2's oncogenic targets. This provides a basis for MSI2 increased dependency in leukemia cells compared to normal cells. Moreover, our study provides a way to measure RBP function in rare cells and suggests that RBPs can achieve differential binding activity during cell state transition independent of gene expression.


Assuntos
Diferenciação Celular/genética , Células-Tronco Hematopoéticas/patologia , Leucemia/genética , Células-Tronco Neoplásicas/patologia , Proteínas de Ligação a RNA/metabolismo , Adenosina Desaminase/genética , Animais , Sítios de Ligação/genética , Modelos Animais de Doenças , Proteínas de Drosophila/genética , Regulação Leucêmica da Expressão Gênica , Redes Reguladoras de Genes , Células HEK293 , Humanos , Leucemia/sangue , Leucemia/patologia , Camundongos , Camundongos Knockout , Cultura Primária de Células , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , RNA-Seq , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo
11.
Biol Blood Marrow Transplant ; 26(7): 1312-1317, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32283185

RESUMO

The COVID-19 pandemic has created significant barriers to timely donor evaluation, cell collection, and graft transport for allogeneic hematopoietic stem cell transplantation (allo-HCT). To ensure availability of donor cells on the scheduled date of infusion, many sites now collect cryopreserved grafts before the start of pretransplantation conditioning. Post-transplantation cyclophosphamide (ptCY) is an increasingly used approach for graft-versus-host disease (GVHD) prophylaxis, but the impact of graft cryopreservation on the outcomes of allo-HCT using ptCY is not known. Using the Center for International Blood and Marrow Transplant Research (CIBMTR) database, we compared the outcomes of HCT using cryopreserved versus fresh grafts in patients undergoing HCT for hematologic malignancy with ptCY. We analyzed 274 patients with hematologic malignancy undergoing allo-HCT between 2013 and 2018 with cryopreserved grafts and ptCY. Eighteen patients received bone marrow grafts and 256 received peripheral blood stem cell grafts. These patients were matched for age, graft type, disease risk index (DRI), and propensity score with 1080 patients who underwent allo-HCT with fresh grafts. The propensity score, which is an assessment of the likelihood of receiving a fresh graft versus a cryopreserved graft, was calculated using logistic regression to account for the following: disease histology, Karnofsky Performance Score (KPS), HCT Comorbidity Index, conditioning regimen intensity, donor type, and recipient race. The primary endpoint was overall survival (OS). Secondary endpoints included acute and chronic graft-versus-host disease (GVHD), non-relapse mortality (NRM), relapse/progression and disease-free survival (DFS). Because of multiple comparisons, only P values <.01 were considered statistically significant. The 2 cohorts (cryopreserved and fresh) were similar in terms of patient age, KPS, diagnosis, DRI, HCT-CI, donor/graft source, and conditioning intensity. One-year probabilities of OS were 71.1% (95% confidence interval [CI], 68.3% to 73.8%) with fresh grafts and 70.3% (95% CI, 64.6% to 75.7%) with cryopreserved grafts (P = .81). Corresponding probabilities of OS at 2 years were 60.6% (95% CI, 57.3% to 63.8%) and 58.7% (95% CI, 51.9% to 65.4%) (P = .62). In matched-pair regression analysis, graft cryopreservation was not associated with a significantly higher risk of mortality (hazard ratio [HR] for cryopreserved versus fresh, 1.05; 95% CI, .86 to 1.29; P = .60). Similarly, rates of neutrophil recovery (HR, .91; 95% CI, .80 to 1.02; P = .12), platelet recovery (HR, .88; 95% CI, .78 to 1.00; P = .05), grade III-IV acute GVHD (HR, .78; 95% CI, .50 to 1.22; P = .27), NRM (HR, 1.16; 95% CI, .86 to 1.55; P = .32) and relapse/progression (HR, 1.21; 95% CI, .97 to 1.50; P = .09) were similar with cryopreserved grafts versus fresh grafts. There were somewhat lower rates of chronic GVHD (HR, 78; 95% CI, .61 to .99; P = .04) and DFS (HR for treatment failure, 1.19; 95% CI, 1.01 to 1.29; P = .04) with graft cryopreservation that were of marginal statistical significance after adjusting for multiple comparisons. Overall, our data indicate that graft cryopreservation does not significantly delay hematopoietic recovery, increase the risk of acute GVHD or NRM, or decrease OS after allo-HCT using ptCY.


Assuntos
Transplante de Medula Óssea/métodos , Infecções por Coronavirus/epidemiologia , Criopreservação/métodos , Doença Enxerto-Hospedeiro/prevenção & controle , Transplante de Células-Tronco Hematopoéticas/métodos , Leucemia/terapia , Linfoma/terapia , Síndromes Mielodisplásicas/terapia , Pneumonia Viral/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Ciclofosfamida/uso terapêutico , Feminino , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/mortalidade , Doença Enxerto-Hospedeiro/patologia , Teste de Histocompatibilidade , Humanos , Leucemia/imunologia , Leucemia/mortalidade , Leucemia/patologia , Linfoma/imunologia , Linfoma/mortalidade , Linfoma/patologia , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/imunologia , Síndromes Mielodisplásicas/mortalidade , Síndromes Mielodisplásicas/patologia , Pandemias , Irmãos , Análise de Sobrevida , Condicionamento Pré-Transplante/métodos , Transplante Homólogo , Estados Unidos/epidemiologia , Doadores não Relacionados/provisão & distribução
12.
Cancer Sci ; 111(7): 2223-2233, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32324315

RESUMO

Invariant natural killer T (iNKT) cells are innate-like CD1d-restricted T cells that express the invariant T cell receptor (TCR) composed of Vα24 and Vß11 in humans. iNKT cells specifically recognize glycolipid antigens such as α-galactosylceramide (αGalCer) presented by CD1d. iNKT cells show direct cytotoxicity toward CD1d-positive tumor cells, especially when CD1d presents glycolipid antigens. However, iNKT cell recognition of CD1d-negative tumor cells is unknown, and direct cytotoxicity of iNKT cells toward CD1d-negative tumor cells remains controversial. Here, we demonstrate that activated iNKT cells recognize leukemia cells in a CD1d-independent manner, however still in a TCR-mediated way. iNKT cells degranulated and released Th1 cytokines toward CD1d-negative leukemia cells (K562, HL-60, REH) as well as αGalCer-loaded CD1d-positive Jurkat cells. The CD1d-independent cytotoxicity was enhanced by natural killer cell-activating receptors such as NKG2D, 2B4, DNAM-1, LFA-1 and CD2, but iNKT cells did not depend on these receptors for the recognition of CD1d-negative leukemia cells. In contrast, TCR was essential for CD1d-independent recognition and cytotoxicity. iNKT cells degranulated toward patient-derived leukemia cells independently of CD1d expression. iNKT cells targeted myeloid malignancies more than acute lymphoblastic leukemia. These findings reveal a novel anti-tumor mechanism of iNKT cells in targeting CD1d-negative tumor cells and indicate the potential of iNKT cells for clinical application to treat leukemia independently of CD1d.


Assuntos
Antígenos CD1d/metabolismo , Leucemia/imunologia , Leucemia/metabolismo , Ativação Linfocitária/imunologia , Células T Matadoras Naturais/imunologia , Células T Matadoras Naturais/metabolismo , Animais , Antígenos CD1d/genética , Biomarcadores , Degranulação Celular , Linhagem Celular Tumoral , Receptores Coestimuladores e Inibidores de Linfócitos T/metabolismo , Citocinas/metabolismo , Citotoxicidade Imunológica , Modelos Animais de Doenças , Feminino , Edição de Genes , Xenoenxertos , Humanos , Imunofenotipagem , Leucemia/genética , Leucemia/patologia , Ativação Linfocitária/genética , Camundongos , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores Desencadeadores da Citotoxicidade Natural/metabolismo
13.
PLoS One ; 15(4): e0232036, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32343715

RESUMO

The NUP98 and NUP214 nucleoporins (NUPs) are recurrently fused to heterologous proteins in leukemia. The resulting chimeric oncoproteins retain the phenylalanine-glycine (FG) repeat motifs of the NUP moiety that mediate interaction with the nuclear export receptor Crm1. NUP fusion leukemias are characterized by HOXA gene upregulation; however, their molecular pathogenesis remains poorly understood. To investigate the role of Crm1 in mediating the leukemogenic properties of NUP chimeric proteins, we took advantage of the Sequestosome-1 (SQSTM1)-NUP214 fusion. SQSTM1-NUP214 retains only a short C-terminal portion of NUP214 which contains FG motifs that mediate interaction with Crm1. We introduced point mutations targeting these FG motifs and found that the ability of the resulting SQSTM1-NUP214FGmut protein to interact with Crm1 was reduced by more than 50% compared with SQSTM1-NUP214. Mutation of FG motifs affected transforming potential: while SQSTM1-NUP214 impaired myeloid maturation and conferred robust colony formation to transduced hematopoietic progenitors in a serial replating assay, the effect of SQSTM1-NUP214FGmut was considerably diminished. Moreover, SQSTM1-NUP214 caused myeloid leukemia in all transplanted mice, whereas none of the SQSTM1-NUP214FGmut reconstituted mice developed leukemia. These oncogenic effects coincided with the ability of SQSTM1-NUP214 and SQSTM1-NUP214FGmut to upregulate the expression of Hoxa and Meis1 genes in hematopoietic progenitors. Indeed, chromatin immunoprecipitation assays demonstrated that impaired SQSTM1-NUP214 interaction with Crm1 correlated with impaired binding of the fusion protein to Hoxa and Meis1 genes. These findings highlight the importance of Crm1 in mediating the leukemogenic properties of SQSTM1-NUP214, and suggest a conserved role of Crm1 in recruiting oncoproteins to their effector genes.


Assuntos
Proteínas de Homeodomínio/genética , Carioferinas/metabolismo , Leucemia/metabolismo , Proteína Meis1/genética , Complexo de Proteínas Formadoras de Poros Nucleares/genética , Proteínas de Fusão Oncogênica/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Proteína Sequestossoma-1/genética , Motivos de Aminoácidos , Animais , Linhagem Celular , Regulação Neoplásica da Expressão Gênica , Leucemia/genética , Leucemia/patologia , Camundongos , Mutagênese Sítio-Dirigida , Transplante de Neoplasias , Complexo de Proteínas Formadoras de Poros Nucleares/química , Proteínas de Fusão Oncogênica/química , Proteínas de Fusão Oncogênica/genética , Mutação Puntual , Regulação para Cima
14.
Trop Doct ; 50(3): 248-249, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32281521

RESUMO

Musculoskeletal complaints may be the initial manifestation of childhood leukaemias. When these symptoms predominate at the onset, a diagnosis of one of several rheumatic diseases may be entertained. Where blood tests are normal, no bone marrow examination would normally be indicated. The use of immune-suppressing medication, such as steroids, may lead to diagnostic delay or misdiagnosis.


Assuntos
Artrite Juvenil/diagnóstico , Artrite Juvenil/patologia , Artrite Juvenil/fisiopatologia , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Leucemia/diagnóstico , Leucemia/patologia , Leucemia/fisiopatologia , Doenças Musculoesqueléticas/diagnóstico , Doenças Musculoesqueléticas/patologia , Doenças Musculoesqueléticas/fisiopatologia , Recidiva
15.
Environ Toxicol ; 35(9): 911-921, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32270916

RESUMO

Leukemia is one of the major diseases causing cancer-related deaths in the young population, and its cure rate is unsatisfying with side effects on patients. Fluorouracil (5-FU) is currently used as an anticancer drug for leukemia patients. Casticin, a natural polymethoxyflavone, exerts anticancer activity against many human cancer cell lines in vitro, but no other reports show 5-FU combined with casticin increased the mouse leukemia cell apoptosis in vitro. Herein, the antileukemia activity of 5-FU combined with casticin in WEHI-3 mouse leukemia cells was investigated in vitro. Treatment of two-drug combination had a higher decrease in cell viability and a higher increase in apoptotic cell death, the level of DNA condensation, and the length of comet tail than that of 5-FU or casticin treatment alone in WEHI-3 cells. In addition, the two-drug combination has a greater production rate of reactive oxygen species but a lower level of Ca2+ release and mitochondrial membrane potential (ΔΨm ) than that of 5-FU alone. Combined drugs also induced higher caspase-3 and caspase-8 activities than that of casticin alone and higher caspase-9 activity than that of 5-FU or casticin alone at 48 hours treatment. Furthermore, 5-FU combined with casticin has a higher expression of Cu/Zn superoxide dismutase (SOD [Cu/Zn]) and lower catalase than that of 5-FU or casticin treatment alone. The combined treatment has higher levels of Bax, Endo G, and cytochrome C of proapoptotic proteins than that of casticin alone and induced lower levels of B-cell lymphoma 2 (BCL-2) and BCL-X of antiapoptotic proteins than that of 5-FU or casticin only. Furthermore, the combined treatment had a higher expression of cleaved poly (ADP-ribose) polymerase (PARP) than that of casticin only. Based on these findings, we may suggest that 5-FU combined with casticin treatment increased apoptotic cell death in WEHI-3 mouse leukemia cells that may undergo mitochondria and caspases signaling pathways in vitro.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Flavonoides/farmacologia , Fluoruracila/farmacologia , Animais , Antineoplásicos/administração & dosagem , Caspases/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citocromos c/metabolismo , Sinergismo Farmacológico , Flavonoides/administração & dosagem , Fluoruracila/administração & dosagem , Humanos , Leucemia/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
16.
Mol Carcinog ; 59(7): 839-851, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32329934

RESUMO

A majority of infant and pediatric leukemias are caused by the mixed-lineage leukemia gene (MLL) fused with a variety of candidates. Several underlying mechanisms have been proposed. One currently popular view is that truncated MLL1 fusion and its associated complex constitutively hijacks super elongation complex, including positive transcription elongation factor b, CDK9, and cyclin T1 complex and DOT1L, to enhance the expression of transcription factors that maintain or restore stemness of leukocytes, as well as prevent the differentiation of hematopoietic progenitor cells. An alternative emerging view proposes that MLL1-fusion promotes the recruitment of TATA binding protein and RNA polymerase II (Pol II) initiation complex, so as to increase the expression levels of target genes. The fundamental mechanism of both theories are gain of function for truncated MLL1 fusions, either through Pol II elongation or initiation. Our recent progress in transcription regulation of paused Pol II through JMJD5, JMJD6, and JMJD7, combined with the repressive role of H3K4me3 revealed by others, prompted us to introduce a contrarian hypothesis: the failure to shut down transcribing units by MLL-fusions triggers the transformation: loss of function of truncated MLL1 fusions coupled with the loss of conversion of H3K4me1 to H3K4me3, leading to the constitutive expression of transcription factors that are in charge of maintenance of hematopoietic progenitor cells, may trigger the transformation of normal cells into cancer cells. Following this track, a potential treatment to eliminate these fusion proteins, which may ultimately cure the disease, is proposed.


Assuntos
Transformação Celular Neoplásica/genética , Leucemia/genética , Proteína de Leucina Linfoide-Mieloide/genética , Proteínas de Fusão Oncogênica/genética , Animais , Histonas/genética , Humanos , Leucemia/patologia
17.
Med Sci Monit ; 26: e921288, 2020 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-32146479

RESUMO

BACKGROUND Leukemia is common in aging adults and has very high mortality worldwide. The present study was designed to investigate the therapeutic efficacy of miR-18a inhibitor against WEHI-3 and THP-1 leukemia cells. MATERIAL AND METHODS The changes in miR-18a inhibitor-transfected WEHI-3 and THP-1 cell proliferative potential was measured by use of the Cell Counting Kit-8 assay. Apoptotic changes were analyzed by electron microscopy, and evaluation of PI3K, AKT, mTOR, and PTEN expression was assessed by RT-qPCR assay. RESULTS Transfection of miR-18a inhibitor significantly (P<0.05) suppressed the proliferative potential of WEHI-3 and THP-1 cells. The WEHI-3 cells showed the presence of characteristic apoptotic bodies on transfection with miR-18a inhibitor at 48 h. Flow cytometry showed that miR-18a inhibitor transfection significantly (P<0.05) increased the WEHI-3 cell percentage in G1 phase. The transfection of miR-18a inhibitor significantly (P<0.05) promoted apoptosis in WEHI-3 cells. In WEHI-3 cells, miR-18a inhibitor transfection markedly suppressed the expression of PI3K, AKT, and mTOR mRNA. The expression of PTEN mRNA was significantly (P<0.05) upregulated by miR-18a inhibitor transfection in WEHI-3 cells. CONCLUSIONS The present study investigated the therapeutic efficacy of miR-18a inhibitor against WEHI-3 and THP1 leukemia cells. The study demonstrated that miR-18a inhibitor suppressed the proliferative potential of WEHI-3 and THP1 cells and activated apoptotic process through upregulation of PTEN mRNA expression. Therefore, miR-18a inhibitor can be of therapeutic importance for the treatment of leukemia.


Assuntos
Proliferação de Células/efeitos dos fármacos , Leucemia/patologia , MicroRNAs/antagonistas & inibidores , PTEN Fosfo-Hidrolase/metabolismo , Apoptose , Regulação Leucêmica da Expressão Gênica , Humanos , Leucemia/tratamento farmacológico , Células THP-1 , Transfecção , Regulação para Cima
18.
Adv Exp Med Biol ; 1219: 259-293, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32130704

RESUMO

The human body requires a constant delivery of fresh blood cells that are needed to maintain body homeostasis. Hematopoiesis is the process that drives the formation of new blood cells from a single stem cell. This is a complex, orchestrated and tightly regulated process that occurs within the bone marrow. When such process is faulty or deregulated, leukemia arises, develops and thrives by subverting normal hematopoiesis and availing the supplies of this rich milieu.In this book chapter we will describe and characterize the bone marrow microenvironment and its key importance for leukemia expansion. The several components of the bone marrow niche, their interaction with the leukemic cells and the cellular pathways activated within the malignant cells will be emphasized. Finally, novel therapeutic strategies to target this sibling interaction will also be discussed.


Assuntos
Medula Óssea/metabolismo , Progressão da Doença , Leucemia/patologia , Microambiente Tumoral , Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Hematopoese/efeitos dos fármacos , Humanos , Leucemia/tratamento farmacológico , Nicho de Células-Tronco/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos
19.
Nat Med ; 26(3): 408-417, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32161403

RESUMO

The diagnosis of lymphomas and leukemias requires hematopathologists to integrate microscopically visible cellular morphology with antibody-identified cell surface molecule expression. To merge these into one high-throughput, highly multiplexed, single-cell assay, we quantify cell morphological features by their underlying, antibody-measurable molecular components, which empowers mass cytometers to 'see' like pathologists. When applied to 71 diverse clinical samples, single-cell morphometric profiling reveals robust and distinct patterns of 'morphometric' markers for each major cell type. Individually, lamin B1 highlights acute leukemias, lamin A/C helps distinguish normal from neoplastic mature T cells, and VAMP-7 recapitulates light-cytometric side scatter. Combined with machine learning, morphometric markers form intuitive visualizations of normal and neoplastic cellular distribution and differentiation. When recalibrated for myelomonocytic blast enumeration, this approach is superior to flow cytometry and comparable to expert microscopy, bypassing years of specialized training. The contextualization of traditional surface markers on independent morphometric frameworks permits more sensitive and automated diagnosis of complex hematopoietic diseases.


Assuntos
Leucemia/diagnóstico , Leucemia/patologia , Linfoma/diagnóstico , Linfoma/patologia , Análise de Célula Única/métodos , Células-Tronco Hematopoéticas/patologia , Humanos , Laminas/metabolismo , Antígenos Comuns de Leucócito/metabolismo , Células Mieloides/patologia , Proteínas R-SNARE/metabolismo
20.
Yakugaku Zasshi ; 140(2): 229-271, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32009046

RESUMO

Outcomes of treatment for malignant pediatric tumors including leukemia are improving by conventional multimodal treatment with strong chemotherapy, surgical resection, radiotherapy, and bone marrow transplantation. However, patients with advanced neuroblastoma, metastatic Ewing's sarcoma family of tumor (ESFT), and metastatic osteosarcoma continue to have an extremely poor prognosis. Therefore novel therapeutic strategies are urgently needed to improve their survival. Apoptotic cell death is a key mechanism for normal cellular homeostasis. Intact apoptotic mechanisms are pivotal for embryonic development, tissue remodeling, immune regulation, and tumor regression. Genetic aberrations disrupting programmed cell death often underpin tumorigenesis and drug resistance. Moreover, it has been suggested that apoptosis or cell differentiation proceeds to spontaneous regression in early stage neuroblastoma. Therefore apoptosis or cell differentiation is a critical event in this cancer. We extracted many compounds from natural plants (Angelica keiskei, Alpinia officiarum, Lycaria puchury-major, Brassica rapa) or synthesized cyclophane pyridine, indirubin derivatives, vitamin K3 derivatives, burchellin derivatives, and GANT61, and examined their effects on apoptosis, cell differentiation, and cell cycle in neuroblastoma and ESFT cell lines compared with normal cells. Some compounds were very effective against these tumor cells. These results suggest that they may be applicable as an efficacious and safe drug for the treatment of malignant pediatric tumors.


Assuntos
Desenvolvimento de Medicamentos , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Apoptose , Diferenciação Celular , Criança , Pré-Escolar , Genes Supressores de Tumor , Humanos , Lactente , Leucemia/tratamento farmacológico , Leucemia/patologia , Neoplasias/patologia , Extratos Vegetais , Prognóstico
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