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2.
Sci Rep ; 11(1): 13958, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34230565

RESUMO

Although the physiological function of the omentum remains elusive, it has been proposed that it plays an important role in fat storage, immune regulation, and regeneration of injured tissues and organs. Although the omentum undergoes expansion upon activation, reports on the accurate assessment of increased cell types and the origin of the increased cells remain limited. To investigate this aspect, the omenta of parabiotic mice were subjected to activation using distinct fluorescent markers and single-cell RNA sequencing (scRNA-seq) was performed to identify circulation-derived omental cells. We found that a considerable number of circulating cells contributed to the activation of the omentum. The omental cells derived from circulating cells exhibited morphological features similar to those of fibroblasts. scRNA-seq revealed the existence of a novel cell population that co-expressed macrophage and fibroblast markers in the activated omentum, suggesting that it corresponded to circulating macrophage-derived fibroblast-like cells. Lineage tracing experiments revealed that most fibroblasts in the activated omentum were not derived from WT1-positive mesenchymal progenitors. The cell cluster also expressed various chemokine genes, indicating its role in the activation and recruitment of immune cells. These results provide important information regarding the activation of the omentum.


Assuntos
Modelos Biológicos , Omento/patologia , Parabiose , Análise de Sequência de RNA , Análise de Célula Única , Adipócitos/patologia , Animais , Fibroblastos/patologia , Camundongos Endogâmicos C57BL , Microscopia Confocal , RNA não Traduzido/genética , RNA não Traduzido/metabolismo , Células-Tronco/patologia
3.
Brain Commun ; 2(1): fcz048, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32954314

RESUMO

Accumulated experience supports the efficacy of allogenic haematopoietic stem cell transplantation in arresting the progression of childhood-onset cerebral form of adrenoleukodystrophy in early stages. For adulthood-onset cerebral form of adrenoleukodystrophy, however, there have been only a few reports on haematopoietic stem cell transplantation and the clinical efficacy and safety of that for adulthood-onset cerebral form of adrenoleukodystrophy remain to be established. To evaluate the clinical efficacy and safety of haematopoietic stem cell transplantation, we conducted haematopoietic stem cell transplantation on 12 patients with adolescent-/adult-onset cerebral form/cerebello-brainstem form of adrenoleukodystrophy in a single-institution-based prospective study. Through careful prospective follow-up of 45 male adrenoleukodystrophy patients, we aimed to enrol patients with adolescent-/adult-onset cerebral form/cerebello-brainstem form of adrenoleukodystrophy at early stages. Indications for haematopoietic stem cell transplantation included cerebral form of adrenoleukodystrophy or cerebello-brainstem form of adrenoleukodystrophy with Loes scores up to 13, the presence of progressively enlarging white matter lesions and/or lesions with gadolinium enhancement on brain MRI. Clinical outcomes of haematopoietic stem cell transplantation were evaluated by the survival rate as well as by serial evaluation of clinical rating scale scores and neurological and MRI findings. Clinical courses of eight patients who did not undergo haematopoietic stem cell transplantation were also evaluated for comparison of the survival rate. All the patients who underwent haematopoietic stem cell transplantation survived to date with a median follow-up period of 28.6 months (4.2-125.3 months) without fatality. Neurological findings attributable to cerebral/cerebellar/brainstem lesions became stable or partially improved in all the patients. Gadolinium-enhanced brain lesions disappeared or became obscure within 3.5 months and the white matter lesions of MRI became stable or small. The median Loes scores before haematopoietic stem cell transplantation and at the last follow-up visit were 6.0 and 5.25, respectively. Of the eight patients who did not undergo haematopoietic stem cell transplantation, six patients died 69.1 months (median period; range 16.0-104.1 months) after the onset of the cerebral/cerebellar/brainstem lesions, confirming that the survival probability was significantly higher in patients with haematopoietic stem cell transplantation compared with that in patients without haematopoietic stem cell transplantation (P = 0.0089). The present study showed that haematopoietic stem cell transplantation was conducted safely and arrested the inflammatory demyelination in all the patients with adolescent-/adult-onset cerebral form/cerebello-brainstem form of adrenoleukodystrophy when haematopoietic stem cell transplantation was conducted in the early stages. Further studies are warranted to optimize the procedures of haematopoietic stem cell transplantation for adolescent-/adult-onset cerebral form/cerebello-brainstem form of adrenoleukodystrophy.

4.
Sci Rep ; 8(1): 15855, 2018 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-30367142

RESUMO

Chronic myelomonocytic leukemia (CMML) is an entity of myelodysplastic syndrome/myeloproliferative neoplasm. Although CMML can be cured with allogeneic stem cell transplantation, its prognosis is generally very poor due to the limited efficacy of chemotherapy and to the patient's age, which is usually not eligible for transplantation. Comprehensive analysis of CMML pathophysiology and the development of therapeutic agents have been limited partly due to the lack of cell lines in CMML and the limited developments of mouse models. After successfully establishing patient's derived disease-specific induced pluripotent stem cells (iPSCs) derived from a patient with CMML, we utilized these CMML-iPSCs to achieve hematopoietic re-differentiation in vitro, created a humanized CMML mouse model via teratomas, and developed a drug-testing system. The clinical characteristics of CMML were recapitulated following hematopoietic re-differentiation in vitro and a humanized CMML mouse model in vivo. The drug-testing system using CMML-iPSCs identified a MEK inhibitor, a Ras inhibitor, and liposomal clodronate as potential drugs for treating CMML. Clodronate is a drug commonly used as a bisphosphonate for osteoporosis. In this study, the liposomalization of clodronate enhanced its effectiveness in these assays, suggesting that this variation of clodronate may be adopted as a repositioned drug for CMML therapy.


Assuntos
Ácido Clodrônico/uso terapêutico , Leucemia Mielomonocítica Crônica/tratamento farmacológico , Lipossomos/química , Inibidores de Proteínas Quinases/uso terapêutico , Idoso , Animais , Diferenciação Celular , Modelos Animais de Doenças , Reposicionamento de Medicamentos , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/transplante , Leucemia Mielomonocítica Crônica/patologia , Leucemia Mielomonocítica Crônica/terapia , Masculino , Camundongos , Neurofibromina 1/metabolismo , Fosforilação , Fator de Transcrição STAT5/metabolismo , Teratoma/metabolismo , Teratoma/patologia , Transplante Heterólogo
5.
Stem Cell Reports ; 10(3): 1115-1130, 2018 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-29429960

RESUMO

Properties of cancer stem cells involved in drug resistance and relapse have significant effects on clinical outcome. Although tyrosine kinase inhibitors (TKIs) have dramatically improved survival of patients with chronic myeloid leukemia (CML), TKIs have not fully cured CML due to TKI-resistant CML stem cells. Moreover, relapse after discontinuation of TKIs has not been predicted in CML patients with the best TKI response. In our study, a model of CML stem cells derived from CML induced pluripotent stem cells identified ADAM8 as an antigen of TKI-resistant CML cells. The inhibition of expression or metalloproteinase activity of ADAM8 restored TKI sensitivity in primary samples. In addition, residual CML cells in patients with optimal TKI response were concentrated in the ADAM8+ population. Our study demonstrates that ADAM8 is a marker of residual CML cells even in patients with optimal TKI response and would be a predictor of relapse and a therapeutic target of TKI-resistant CML cells.


Assuntos
Proteínas ADAM/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Proteínas de Membrana/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células K562 , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo
6.
Sci Rep ; 7(1): 9891, 2017 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-28860595

RESUMO

The murine intestine, like that of other mammalians, continues to develop after birth until weaning; however, whether this occurs in response to an intrinsic developmental program or food intake remains unclear. Here, we report a novel system for the allotransplantation of small intestine and colon harvested from Lgr5 EGFP-IRES-CreERT2/+; Rosa26 rbw/+ mice immediately after birth into the subrenal capsule of wild-type mice. By histological and immunohistochemical analysis, the developmental process of transplanted small intestine and colon was shown to be comparable with that of the native tissues: mature intestines equipped with all cell types were formed, indicating that these organs do not require food intake for development. The intestinal stem cells in transplanted tissues were shown to self-renew and produce progeny, resulting in the descendants of the stem cells occupying the crypt-villus unit of the small intestine or the whole crypt of the colon. Collectively, these findings indicate that neonatal intestine development follows an intrinsic program even in the absence of food stimuli.


Assuntos
Diferenciação Celular , Colo/citologia , Colo/fisiologia , Intestino Delgado/citologia , Intestino Delgado/fisiologia , Células-Tronco/citologia , Células-Tronco/metabolismo , Aloenxertos , Animais , Animais Recém-Nascidos , Biomarcadores , Proliferação de Células , Digestão , Imunofluorescência , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Camundongos
7.
Sci Rep ; 7: 41838, 2017 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-28176811

RESUMO

Although the existence of cancer stem cells in intestine tumors has been suggested, direct evidence has not been yet provided. Here, we showed, using the multicolor lineage-tracing method and mouse models of intestinal adenocarcinoma and adenoma that Bmi1- or Lgr5- positive tumorigenic cells clonally expanded in proliferating tumors. At tumor initiation and during tumor propagation in the colon, the descendants of Lgr5-positive cells clonally proliferated to form clusters. Clonal analysis using ubiquitous multicolor lineage tracing revealed that colon tumors derived from Lgr5-positive cells were monoclonal in origin but eventually merged with neighboring tumors, producing polyclonal tumors at the later stage. In contrast, the origin of small intestine tumors was likely polyclonal, and during cancer progression some clones were eliminated, resulting in the formation of monoclonal tumors, which could merge similar to colon tumors. These results suggest that in proliferating intestinal neoplasms, Bmi1- or Lgr5-positive cells represent a population of cancer stem cells, whereas Lgr5-positive cells also function as cells-of-origin for intestinal tumors.


Assuntos
Biomarcadores Tumorais/genética , Evolução Clonal , Neoplasias Intestinais/genética , Células-Tronco Neoplásicas/metabolismo , Complexo Repressor Polycomb 1/genética , Proteínas Proto-Oncogênicas/genética , Receptores Acoplados a Proteínas G/genética , Animais , Biomarcadores Tumorais/metabolismo , Proliferação de Células , Células Cultivadas , Neoplasias Intestinais/metabolismo , Neoplasias Intestinais/patologia , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neoplásicas/citologia , Complexo Repressor Polycomb 1/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo
8.
Sci Rep ; 6: 39386, 2016 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-28004815

RESUMO

We recently reported that the polycomb complex protein Bmi1 is a marker for lingual epithelial stem cells (LESCs), which are involved in the long-term maintenance of lingual epithelial tissue in the physiological state. However, the precise role of LESCs in generating tongue tumors and Bmi1-positive cell lineage dynamics in tongue cancers are unclear. Here, using a mouse model of chemically (4-nitroquinoline-1-oxide: 4-NQO) induced tongue cancer and the multicolor lineage tracing method, we found that each unit of the tumor was generated by a single cell and that the assembly of such cells formed a polyclonal tumor. Although many Bmi1-positive cells within the tongue cancer specimens failed to proliferate, some proliferated continuously and supplied tumor cells to the surrounding area. This process eventually led to the formation of areas derived from single cells after 1-3 months, as determined using the multicolor lineage tracing method, indicating that such cells could serve as cancer stem cells. These results indicate that LESCs could serve as the origin for tongue cancer and that cancer stem cells are present in tongue tumors.


Assuntos
Linhagem da Célula/fisiologia , Epitélio/metabolismo , Células-Tronco Neoplásicas/metabolismo , Complexo Repressor Polycomb 1/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Neoplasias da Língua/metabolismo , 4-Nitroquinolina-1-Óxido/farmacologia , Animais , Proliferação de Células/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Língua/metabolismo , Neoplasias da Língua/induzido quimicamente
9.
Biochem Biophys Res Commun ; 466(3): 333-8, 2015 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-26362184

RESUMO

The skin is responsible for a variety of physiological functions and is critical for wound healing and repair. Therefore, the regenerative capacity of the skin is important. However, stem cells responsible for maintaining the acral epithelium had not previously been identified. In this study, we identified the specific stem cells in the acral epithelium that participate in the long-term maintenance of sweat glands, ducts, and interadnexal epidermis and that facilitate the regeneration of these structures following injury. Lgr6-positive cells and Bmi1-positive cells were found to function as long-term multipotent stem cells that maintained the entire eccrine unit and the interadnexal epidermis. However, while Lgr6-positive cells were rapidly cycled and constantly supplied differentiated cells, Bmi1-positive cells were slow to cycle and occasionally entered the cell cycle under physiological conditions. Upon irradiation-induced injury, Bmi1-positive cells rapidly proliferated and regenerated injured epithelial tissue. Therefore, Bmi1-positive stem cells served as reservoir stem cells. Lgr5-positive cells were rapidly cycled and maintained only sweat glands; therefore, we concluded that these cells functioned as lineage-restricted progenitors. Taken together, our data demonstrated the identification of stem cells that maintained the entire acral epithelium and supported the different roles of three cellular classes.


Assuntos
Epitélio/metabolismo , Complexo Repressor Polycomb 1/fisiologia , Proteínas Proto-Oncogênicas/fisiologia , Receptores Acoplados a Proteínas G/fisiologia , Células-Tronco/citologia , Glândulas Sudoríparas/fisiologia , Animais , Peso Corporal , Linhagem da Célula , Proliferação de Células , Epiderme/metabolismo , Feminino , Regulação da Expressão Gênica , Imageamento Tridimensional , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Células-Tronco Multipotentes/citologia , Complexo Repressor Polycomb 1/genética , Proteínas Proto-Oncogênicas/genética , Receptores Acoplados a Proteínas G/genética , Pele/metabolismo
10.
Exp Hematol ; 43(10): 849-57, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26021490

RESUMO

Familial platelet disorder with propensity to acute myeloid leukemia (FPD/AML) is an autosomal dominant disease associated with a germline mutation in the RUNX1 gene and is characterized by thrombocytopenia and an increased risk of developing myeloid malignancies. We generated induced pluripotent stem cells (iPSCs) from dermal fibroblasts of a patient with FPD/AML possessing a nonsense mutation R174X in the RUNX1 gene. Consistent with the clinical characteristics of the disease, FPD iPSC-derived hematopoietic progenitor cells were significantly impaired in undergoing megakaryocytic differentiation and subsequent maturation, as determined by colony-forming cell assay and surface marker analysis. Notably, when we corrected the RUNX1 mutation using transcription activator-like effector nucleases in conjunction with a donor plasmid containing normal RUNX1 cDNA sequences, megakaryopoiesis and subsequent maturation were restored in FPD iPSC-derived hematopoietic cells. These findings clearly indicate that the RUNX1 mutation is robustly associated with thrombocytopenia in patients with FPD/AML, and transcription activator-like effector nuclease-mediated gene correction in iPSCs generated from patient-derived cells could provide a promising clinical application for treatment of the disease.


Assuntos
Transtornos Herdados da Coagulação Sanguínea , Transtornos Plaquetários , Códon sem Sentido , Subunidade alfa 2 de Fator de Ligação ao Core , Terapia Genética/métodos , Células-Tronco Pluripotentes Induzidas/metabolismo , Leucemia Mieloide Aguda , Trombopoese/genética , Adulto , Transtornos Herdados da Coagulação Sanguínea/genética , Transtornos Herdados da Coagulação Sanguínea/metabolismo , Transtornos Herdados da Coagulação Sanguínea/patologia , Transtornos Herdados da Coagulação Sanguínea/terapia , Transtornos Plaquetários/genética , Transtornos Plaquetários/metabolismo , Transtornos Plaquetários/patologia , Transtornos Plaquetários/terapia , Subunidade alfa 2 de Fator de Ligação ao Core/biossíntese , Subunidade alfa 2 de Fator de Ligação ao Core/genética , DNA Complementar/genética , Feminino , Humanos , Células-Tronco Pluripotentes Induzidas/patologia , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/terapia
11.
Cancer Sci ; 106(5): 489-96, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25707772

RESUMO

In recent years, several molecularly targeted therapies have been developed as part of lung cancer treatment; they have produced dramatically good results. However, among the many oncogenes that have been identified to be involved in the development of lung cancers, a number of oncogenes are not covered by these advanced therapies. For the treatment of lung cancers, which is a group of heterogeneous diseases, persistent effort in developing individual therapies based on the respective causal genes is important. In addition, for the development of a novel therapy, identification of the lung epithelial stem cells and the origin cells of lung cancer, and understanding about candidate cancer stem cells in lung cancer tissues, their intracellular signaling pathways, and the mechanism of dysregulation of the pathways in cancer cells are extremely important. However, the development of drug resistance by cancer cells, despite the use of molecularly targeted drugs for the causal genes, thus obstructing treatment, is a well-known phenomenon. In this article, we discuss major causal genes of lung cancers and intracellular signaling pathways involving those genes, and review studies on origin and stem cells of lung cancers, as well as the possibility of developing molecularly targeted therapies based on these studies.


Assuntos
Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Animais , Caderinas/genética , Caderinas/metabolismo , Resistencia a Medicamentos Antineoplásicos , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/patologia , Camundongos , MicroRNAs/metabolismo , Terapia de Alvo Molecular/métodos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Proteínas Tirosina Quinases/metabolismo , Receptores Notch/genética , Receptores Notch/metabolismo , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais , Via de Sinalização Wnt
12.
Sci Rep ; 4: 6175, 2014 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-25146451

RESUMO

Asingle cells in undifferentiated spermatogonia are considered to be the most primitive forms of germ stem cells (GSCs). Although GFRα1 is thought to be a marker of Asingle cells, we found that Bmi1(High) is more specific than GFRα1 for Asingle cells. Bmi1(High) expression in Asingle cells is correlated with seminiferous stages, and its expression was followed by the proliferative stage of Asingle GSCs. In contrast, GFRα1 expression was seminiferous stage-independent. Fate analyses of EdU-positive Bmi1(High)-positive cell-derived Asingle cells revealed that these cells self-renewed or generated transient amplifying Apaired cells. Bmi1(High)-positive cells were resistant to irradiation-induced injury, after which they regenerated. Elimination of Bmi1(High)-positive cells from seminiferous tubules resulted in the appearance of tubules with seminiferous stage mismatches. Thus, in this study, we found that Bmi1(High) is a seminiferous stage-dependent marker for long-term GSCs and that Bmi1(High)-positive cells play important roles in maintaining GSCs and in regenerating spermatogenic progenitors after injury.


Assuntos
Expressão Gênica , Células Germinativas/metabolismo , Complexo Repressor Polycomb 1/genética , Proteínas Proto-Oncogênicas/genética , Células-Tronco/metabolismo , Animais , Diferenciação Celular , Linhagem da Célula , Proliferação de Células , Deleção de Genes , Células Germinativas/citologia , Células Germinativas/efeitos da radiação , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Imunofenotipagem , Masculino , Camundongos , Camundongos Transgênicos , Complexo Repressor Polycomb 1/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Regeneração , Túbulos Seminíferos/citologia , Espermatogônias/citologia , Espermatogônias/metabolismo , Espermatogônias/efeitos da radiação , Células-Tronco/citologia , Células-Tronco/efeitos da radiação
13.
Exp Hematol ; 42(9): 816-25, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24859480

RESUMO

Induced pluripotent stem cells (iPS) derived from disease cells are expected to provide a new experimental material, especially for diseases from which samples are difficult to obtain. In this study, we generated iPS from samples from patients with primary and secondary myelofibrosis. The primary myelofibrosis cells had chromosome 13q deletions, and the secondary myelofibrosis (SMF) cells had JAK2V617F mutations. The myelofibrosis patient cell-derived iPS (MF-iPS) were confirmed as possessing these parental disease-specific genomic markers. The capacity to form three germ layers was confirmed by teratoma assay. By co-culture with specific feeder cells and cytokines, MF-iPS can re-differentiate into blood progenitor cells and finally into megakaryocytes. We found that mRNA levels of interleukin-8, one of the candidate cytokines related to the pathogenesis of myelofibrosis, was elevated predominantly in megakaryocytes derived from MF-iPS. Because megakaryocytes from myelofibrosis clones are considered to produce critical mediators to proliferate fibroblasts in the bone marrow and iPS can provide differentiated cells abundantly, the disease-specific iPS we established should be a good research tool for this intractable disease.


Assuntos
Deleção Cromossômica , Transtornos Cromossômicos , Células-Tronco Pluripotentes Induzidas , Janus Quinase 2 , Mutação de Sentido Incorreto , Mielofibrose Primária , Adulto , Substituição de Aminoácidos , Células Cultivadas , Transtornos Cromossômicos/genética , Transtornos Cromossômicos/metabolismo , Transtornos Cromossômicos/patologia , Cromossomos Humanos Par 13/genética , Cromossomos Humanos Par 13/metabolismo , Técnicas de Cocultura , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/patologia , Interleucina-8/genética , Interleucina-8/metabolismo , Janus Quinase 2/genética , Masculino , Megacariócitos/metabolismo , Megacariócitos/patologia , Pessoa de Meia-Idade , Mielofibrose Primária/genética , Mielofibrose Primária/metabolismo , Mielofibrose Primária/patologia , Teratoma
14.
Blood ; 123(16): 2540-9, 2014 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-24574458

RESUMO

Just as normal stem cells require niche cells for survival, leukemia-initiating cells (LICs) may also require niche cells for their maintenance. Chronic myeloid leukemia (CML) is caused by the activity of BCR-ABL, a constitutively active tyrosine kinase. CML therapy with tyrosine kinase inhibitors is highly effective; however, due to the persistence of residual LICs, it is not curative. Several factors are known to support CML LICs, but purification of LICs and a thorough understanding of their niche signals have not yet been achieved. Using a CML-like mouse model of myeloproliferative disease, we demonstrate that CML LICs can be divided into CD25(+)FcεRIα(-) Lineage marker (Lin)(-) Sca-1(+)c-Kit(+) (F(-)LSK) cells and CD25(-)F(-)LSK cells. The CD25(+)F(-)LSK cells had multilineage differentiation capacity, with a preference toward cytokine-producing mast cell commitment. Although cells interconverted between CD25(-)F(-)LSK and CD25(+)F(-)LSK status, the CD25(+)F(-)LSK cells exhibited higher LIC capacity. Our findings suggest that interleukin-2 derived from the microenvironment and CD25 expressed on CML LICs constitute a novel signaling axis. The high levels of CD25 expression in the CD34(+)CD38(-) fraction of human CML cells indicate that CD25(+) LICs constitute an "LIC-derived niche" that could be preferentially targeted in therapy for CML.


Assuntos
Subunidade alfa de Receptor de Interleucina-2/fisiologia , Interleucina-2/fisiologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Células-Tronco Neoplásicas/patologia , Células-Tronco Neoplásicas/fisiologia , Animais , Proliferação de Células , Células Cultivadas , Regulação Leucêmica da Expressão Gênica , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células-Tronco Neoplásicas/metabolismo , Transdução de Sinais/fisiologia , Células Th2/metabolismo , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia
15.
J Clin Invest ; 124(2): 528-42, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24382349

RESUMO

Acute myeloid leukemia (AML) is a heterogeneous hematologic malignancy that originates from leukemia-initiating cells (LICs). The identification of common mechanisms underlying LIC development will be important in establishing broadly effective therapeutics for AML. Constitutive NF-κB pathway activation has been reported in different types of AML; however, the mechanism of NF-κB activation and its importance in leukemia progression are poorly understood. Here, we analyzed myeloid leukemia mouse models to assess NF-κB activity in AML LICs. We found that LICs, but not normal hematopoietic stem cells or non-LIC fractions within leukemia cells, exhibited constitutive NF-κB activity. This activity was maintained through autocrine TNF-α secretion, which formed an NF-κB/TNF-α positive feedback loop. LICs had increased levels of active proteasome machinery, which promoted the degradation of IκBα and further supported NF-κB activity. Pharmacological inhibition of the proteasome complex markedly suppressed leukemia progression in vivo. Conversely, enhanced activation of NF-κB signaling expanded LIC frequency within leukemia cell populations. We also demonstrated a strong correlation between NF-κB activity and TNF-α secretion in human AML samples. Our findings indicate that NF-κB/TNF-α signaling in LICs contributes to leukemia progression and provide a widely applicable approach for targeting LICs.


Assuntos
Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide Aguda/metabolismo , NF-kappa B/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Transporte Ativo do Núcleo Celular , Adulto , Idoso , Animais , Células da Medula Óssea/metabolismo , Ácidos Borônicos/uso terapêutico , Bortezomib , Progressão da Doença , Feminino , Células-Tronco Hematopoéticas/citologia , Humanos , Leucemia/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia de Fluorescência , Pessoa de Meia-Idade , Fenótipo , Complexo de Endopeptidases do Proteassoma/química , Pirazinas/uso terapêutico , Transdução de Sinais , Fatores de Tempo
18.
Int J Hematol ; 98(2): 145-52, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23807288

RESUMO

Induced pluripotent stem cells (iPSCs) can be generated from various types of cells with transduction of defined transcription factors. In addition to regenerative medicine, iPSCs have been used for the study of pathogenesis of inherited genetic diseases. Here, we presented the examples of the establishment of iPSCs from hematopoietic cells or fibroblasts from hematological disease patients. Hematopoietic cells would be a good donor source for establishing iPSCs owing to the high reprogramming efficiency. iPSCs can be generated not only from normal cells, but also from several types of tumor cells. However it is not so easy, because iPSCs from hematological malignancies have been established only from myeloproliferative neoplasms including chronic myelogenous leukemia (CML) and JAK2-V617F mutation-positive polycythemia vera (PV). iPSC technology has great potential to promote oncology research based on patient samples.


Assuntos
Células-Tronco Hematopoéticas , Células-Tronco Pluripotentes Induzidas , Janus Quinase 2 , Leucemia Mielogênica Crônica BCR-ABL Positiva , Células-Tronco Neoplásicas , Substituição de Aminoácidos , Animais , Células-Tronco Hematopoéticas/enzimologia , Células-Tronco Hematopoéticas/patologia , Humanos , Células-Tronco Pluripotentes Induzidas/enzimologia , Células-Tronco Pluripotentes Induzidas/patologia , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/enzimologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Mutação de Sentido Incorreto , Células-Tronco Neoplásicas/enzimologia , Células-Tronco Neoplásicas/patologia
19.
Blood ; 121(20): 4142-55, 2013 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-23547050

RESUMO

Ecotropic viral integration site 1 (Evi1) is one of the master regulators in the development of acute myeloid leukemia (AML) and myelodysplastic syndrome. High expression of Evi1 is found in 10% of patients with AML and indicates a poor outcome. Several recent studies have indicated that Evi1 requires collaborative factors to induce AML. Therefore, the search for candidate factors that collaborate with Evi1 in leukemogenesis is one of the key issues in uncovering the mechanism of Evi1-related leukemia. Previously, we succeeded in making a mouse model of Evi1-related leukemia using a bone marrow transplantation (BMT) system. In the Evi1-induced leukemic cells, we identified frequent retroviral integrations near the CCAAT/enhancer-binding protein ß (C/EBPß) gene and overexpression of its protein. These findings imply that C/EBPß is a candidate gene that collaborates with Evi1 in leukemogenesis. Cotransduction of Evi1 and the shortest isoform of C/EBPß, liver inhibitory protein (LIP), induced AML with short latencies in a mouse BMT model. Overexpression of LIP alone also induced AML with longer latencies. However, excision of all 3 isoforms of C/EBPß (LAP*/LAP/LIP) did not inhibit the development of Evi1-induced leukemia. Therefore, isoform-specific intervention that targets LIP is required when we consider C/EBPß as a therapeutic target.


Assuntos
Transplante de Medula Óssea , Proteína beta Intensificadora de Ligação a CCAAT/fisiologia , Transformação Celular Neoplásica/genética , Proteínas de Ligação a DNA/fisiologia , Leucemia Mieloide Aguda/genética , Proto-Oncogenes/fisiologia , Fatores de Transcrição/fisiologia , Animais , Transplante de Medula Óssea/efeitos adversos , Transplante de Medula Óssea/patologia , Proteína beta Intensificadora de Ligação a CCAAT/genética , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Células Cultivadas , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Regulação Leucêmica da Expressão Gênica , Humanos , Leucemia Mieloide Aguda/etiologia , Leucemia Mieloide Aguda/patologia , Proteína do Locus do Complexo MDS1 e EVI1 , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Biológicos , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Isoformas de Proteínas/fisiologia , Proto-Oncogenes/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
20.
Blood ; 119(26): 6234-42, 2012 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-22592606

RESUMO

Induced pluripotent stem cells (iPSCs) can be generated by the expression of defined transcription factors not only from normal tissue, but also from malignant cells. Cancer-derived iPSCs are expected to provide a novel experimental opportunity to establish the disease model. We generated iPSCs from imatinib-sensitive chronic myelogenous leukemia (CML) patient samples. Remarkably, the CML-iPSCs were resistant to imatinib although they consistently expressed BCR-ABL oncoprotein. In CML-iPSCs, the phosphorylation of ERK1/2, AKT, and JNK, which are essential for the maintenance of both BCR-ABL (+) leukemia cells and iPSCs, were unchanged after imatinib treatment, whereas the phosphorylation of signal transducer and activator of transcription (STAT)5 and CRKL was significantly decreased. These results suggest that the signaling for iPSCs maintenance compensates for the inhibition of BCR-ABL. CML-iPSC-derived hematopoietic cells recovered the sensitivity to imatinib although CD34(+)38(-)90(+)45(+) immature cells were resistant to imatinib, which recapitulated the pathophysiologic feature of the initial CML. CML-iPSCs provide us with a novel platform to investigate CML pathogenesis on the basis of patient-derived samples.


Assuntos
Células-Tronco Pluripotentes Induzidas/patologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Cultura Primária de Células/métodos , Animais , Butadienos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Cromonas/farmacologia , Análise por Conglomerados , Técnicas de Cocultura , Inibidores Enzimáticos/farmacologia , Perfilação da Expressão Gênica , Hematopoese/efeitos dos fármacos , Hematopoese/fisiologia , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/fisiologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Camundongos , Análise em Microsséries , Modelos Teóricos , Morfolinas/farmacologia , Nitrilas/farmacologia
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