Soluble triggering receptor expressed on myeloid cells (s-TREM-1 ...

African Journals Online (AJOL)

2010-10-08

Oct 8, 2010 ... antimicrobial therapy. Soluble .... organophosphate poisoning, extradural haemorrhage ... with a CPIS ≥6 should be treated empirically with .... for ventilator-associated pneumonia: accuracy and inter-observer variability.

UV light B-mediated inhibition of skin catalase activity promotes Gr-1+ CD11b+ myeloid cell expansion.

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Sullivan, Nicholas J; Tober, Kathleen L; Burns, Erin M; Schick, Jonathan S; Riggenbach, Judith A; Mace, Thomas A; Bill, Matthew A; Young, Gregory S; Oberyszyn, Tatiana M; Lesinski, Gregory B

2012-03-01

Skin cancer incidence and mortality are higher in men compared with women, but the causes of this sex discrepancy remain largely unknown. UV light exposure induces cutaneous inflammation and neutralizes cutaneous antioxidants. Gr-1(+)CD11b(+) myeloid cells are heterogeneous bone marrow-derived cells that promote inflammation-associated carcinogenesis. Reduced activity of catalase, an antioxidant present in the skin, has been associated with skin carcinogenesis. We used the outbred, immune-competent Skh-1 hairless mouse model of UVB-induced inflammation and non-melanoma skin cancer to further define sex discrepancies in UVB-induced inflammation. Our results demonstrated that male skin had relatively lower baseline catalase activity, which was inhibited following acute UVB exposure in both sexes. Further analysis revealed that skin catalase activity inversely correlated with splenic Gr-1(+)CD11b(+) myeloid cell percentage. Acute UVB exposure induced Gr-1(+)CD11b(+) myeloid cell skin infiltration, which was inhibited to a greater extent in male mice by topical catalase treatment. In chronic UVB studies, we demonstrated that the percentage of splenic Gr-1(+)CD11b(+) myeloid cells was 55% higher in male tumor-bearing mice compared with their female counterparts. Together, our findings indicate that lower skin catalase activity in male mice may at least in part contribute to increased UVB-induced generation of Gr-1(+)CD11b(+) myeloid cells and subsequent skin carcinogenesis.

Regulatory Myeloid Cells in Transplantation

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Rosborough, Brian R.; Raïch-Regué, Dàlia; Turnquist, Heth R.; Thomson, Angus W.

2013-01-01

Regulatory myeloid cells (RMC) are emerging as novel targets for immunosuppressive (IS) agents and hold considerable promise as cellular therapeutic agents. Herein, we discuss the ability of regulatory macrophages (Mreg), regulatory dendritic cells (DCreg) and myeloid-derived suppressor cells (MDSC) to regulate alloimmunity, their potential as cellular therapeutic agents and the IS agents that target their function. We consider protocols for the generation of RMC and the selection of donor- or recipient-derived cells for adoptive cell therapy. Additionally, the issues of cell trafficking and antigen (Ag) specificity following RMC transfer are discussed. Improved understanding of the immunobiology of these cells has increased the possibility of moving RMC into the clinic to reduce the burden of current IS agents and promote Ag-specific tolerance. In the second half of this review, we discuss the influence of established and experimental IS agents on myeloid cell populations. IS agents believed historically to act primarily on T cell activation and proliferation are emerging as important regulators of RMC function. Better insights into the influence of IS agents on RMC will enhance our ability to develop cell therapy protocols to promote the function of these cells. Moreover, novel IS agents may be designed to target RMC in situ to promote Ag-specific immune regulation in transplantation and usher in a new era of immune modulation exploiting cells of myeloid origin. PMID:24092382

Colony stimulating factor 1 receptor inhibition delays recurrence of glioblastoma after radiation by altering myeloid cell recruitment and polarization

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Stafford, Jason H.; Hirai, Takahisa; Deng, Lei; Chernikova, Sophia B.; Urata, Kimiko; West, Brian L.; Brown, J. Martin

2016-01-01

Background Glioblastoma (GBM) may initially respond to treatment with ionizing radiation (IR), but the prognosis remains extremely poor because the tumors invariably recur. Using animal models, we previously showed that inhibiting stromal cell–derived factor 1 signaling can prevent or delay GBM recurrence by blocking IR-induced recruitment of myeloid cells, specifically monocytes that give rise to tumor-associated macrophages. The present study was aimed at determining if inhibiting colony stimulating factor 1 (CSF-1) signaling could be used as an alternative strategy to target pro-tumorigenic myeloid cells recruited to irradiated GBM. Methods To inhibit CSF-1 signaling in myeloid cells, we used PLX3397, a small molecule that potently inhibits the tyrosine kinase activity of the CSF-1 receptor (CSF-1R). Combined IR and PLX3397 therapy was compared with IR alone using 2 different human GBM intracranial xenograft models. Results GBM xenografts treated with IR upregulated CSF-1R ligand expression and increased the number of CD11b+ myeloid-derived cells in the tumors. Treatment with PLX3397 both depleted CD11b+ cells and potentiated the response of the intracranial tumors to IR. Median survival was significantly longer for mice receiving combined therapy versus IR alone. Analysis of myeloid cell differentiation markers indicated that CSF-1R inhibition prevented IR-recruited monocyte cells from differentiating into immunosuppressive, pro-angiogenic tumor-associated macrophages. Conclusion CSF-1R inhibition may be a promising strategy to improve GBM response to radiotherapy. PMID:26538619

CAR-T cells targeting CLL-1 as an approach to treat acute myeloid leukemia

OpenAIRE

Wang, Jinghua; Chen, Siyu; Xiao, Wei; Li, Wende; Wang, Liang; Yang, Shuo; Wang, Weida; Xu, Liping; Liao, Shuangye; Liu, Wenjian; Wang, Yang; Liu, Nawei; Zhang, Jianeng; Xia, Xiaojun; Kang, Tiebang

2018-01-01

Background Acute myeloid leukemia (AML) is one of the most common types of adult acute leukemia. Standard chemotherapies can induce complete remission in selected patients; however, a majority of patients eventually relapse and succumb to the disease. Thus, the development of novel therapeutics for AML is urgently needed. Human C-type lectin-like molecule-1 (CLL-1) is a type II transmembrane glycoprotein, and its expression is restricted to myeloid cells and the majority of AML blasts. Moreov...

Leishmania Hijacks Myeloid Cells for Immune Escape

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María Martínez-López

2018-05-01

Full Text Available Protozoan parasites of the Leishmania genus are the causative agents of leishmaniasis, a group of neglected tropical diseases whose clinical manifestations vary depending on the infectious Leishmania species but also on host factors. Recognition of the parasite by host myeloid immune cells is a key to trigger an effective Leishmania-specific immunity. However, the parasite is able to persist in host myeloid cells by evading, delaying and manipulating host immunity in order to escape host resistance and ensure its transmission. Neutrophils are first in infiltrating infection sites and could act either favoring or protecting against infection, depending on factors such as the genetic background of the host or the parasite species. Macrophages are the main host cells where the parasites grow and divide. However, macrophages are also the main effector population involved in parasite clearance. Parasite elimination by macrophages requires the priming and development of an effector Th1 adaptive immunity driven by specific subtypes of dendritic cells. Herein, we will provide a comprehensive outline of how myeloid cells regulate innate and adaptive immunity against Leishmania, and the mechanisms used by the parasites to promote their evasion and sabotage. Understanding the interactions between Leishmania and the host myeloid cells may lead to the development of new therapeutic approaches and improved vaccination to leishmaniases, an important worldwide health problem in which current therapeutic or preventive approaches are limited.

Urine TREM-1 as a marker of urinary tract infection in children.

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Sierra-Diaz, Erick; Bravo Cuéllar, Alejandro; Ortiz Lazareno, Pablo Cesar; García Gutiérrez, Mariana; Georgina, Hernandez Flores; Anaya Prado, Roberto

2017-04-01

Objective Triggering receptor expressed on myeloid cells (TREM)-1 is a receptor that is thought to improve recognition of patients with true infection. In this study, we investigated whether Triggering receptor expressed on myeloid cells (TREM-1) is present in urine samples from children with urinary tract infection (UTI) and in samples from healthy children. Methods A total of 128 samples met the inclusion criteria for the study. Urine samples were processed for culture and urinalysis as a regular protocol for patients with UTI. Samples were classified according to culture and urinalysis results. TREM-1 protein expression was detected with flow cytometry and sTREM-1 was assessed by ELISA. Results Flow cytometry showed detectable expression of TREM-1 in 100% of samples, UTI and non-UTI groups ( p UTI, but not in non-UTI patients. Conclusions All of our patients (healthy and diseased) showed TREM-1 expression. However, TREM-1 levels in patients with UTI tend to be higher and are associated with increased neutrophils and cytokine activity induced by bacteria.

An AML1-ETO/miR-29b-1 regulatory circuit modulates phenotypic properties of acute myeloid leukemia cells.

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Zaidi, Sayyed K; Perez, Andrew W; White, Elizabeth S; Lian, Jane B; Stein, Janet L; Stein, Gary S

2017-06-20

Acute myeloid leukemia (AML) is characterized by an aggressive clinical course and frequent cytogenetic abnormalities that include specific chromosomal translocations. The 8;21 chromosomal rearrangement disrupts the key hematopoietic RUNX1 transcription factor, and contributes to leukemia through recruitment of co-repressor complexes to RUNX1 target genes, altered subnuclear localization, and deregulation of the myeloid gene regulatory program. However, a role of non-coding microRNAs (miRs) in t(8;21)-mediated leukemogenesis is minimally understood. We present evidence of an interplay between the tumor suppressor miR-29b-1 and the AML1-ETO (also designated RUNX1-RUNX1T1) oncogene that is encoded by the t(8;21). We find that AML1-ETO and corepressor NCoR co-occupy the miR-29a/b-1 locus and downregulate its expression in leukemia cells. Conversely, re-introduction of miR-29b-1 in leukemia cells expressing AML1-ETO causes significant downregulation at the protein level through direct targeting of the 3' untranslated region of the chimeric transcript. Restoration of miR-29b-1 expression in leukemia cells results in decreased cell growth and increased apoptosis. The AML1-ETO-dependent differentiation block and transcriptional program are partially reversed by miR-29b-1. Our findings establish a novel regulatory circuit between the tumor-suppressive miR-29b-1 and the oncogenic AML1-ETO that controls the leukemic phenotype in t(8;21)-carrying acute myeloid leukemia.

Lumbar Myeloid Cell Trafficking into Locomotor Networks after Thoracic Spinal Cord Injury

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Hansen, Christopher N.; Norden, Diana M.; Faw, Timothy D.; Deibert, Rochelle; S.Wohleb, Eric; Sheridan, John F.; P.Godbout, Jonathan; Basso, D. Michele

2016-01-01

Spinal cord injury (SCI) promotes inflammation along the neuroaxis that jeopardizes plasticity, intrinsic repair and recovery. While inflammation at the injury site is well-established, less is known within remote spinal networks. The presence of bone marrow-derived immune (myeloid) cells in these areas may further impede functional recovery. Previously, high levels of the gelatinase, matrix metalloproteinase-9 (MMP-9) occurred within the lumbar enlargement after thoracic SCI and impeded activity-dependent recovery. Since SCI-induced MMP-9 potentially increases vascular permeability, myeloid cell infiltration may drive inflammatory toxicity in locomotor networks. Therefore, we examined neurovascular reactivity and myeloid cell infiltration in the lumbar cord after thoracic SCI. We show evidence of region-specific recruitment of myeloid cells into the lumbar but not cervical region. Myeloid infiltration occurred with concomitant increases in chemoattractants (CCL2) and cell adhesion molecules (ICAM-1) around lumbar vasculature 24 hours and 7 days post injury. Bone marrow GFP chimeric mice established robust infiltration of bone marrow-derived myeloid cells into the lumbar gray matter 24 hours after SCI. This cell infiltration occurred when the blood-spinal cord barrier was intact, suggesting active recruitment across the endothelium. Myeloid cells persisted as ramified macrophages at 7 days post injury in parallel with increased inhibitory GAD67 labeling. Importantly, macrophage infiltration required MMP-9. PMID:27191729

Cytokine Networks between Innate Lymphoid Cells and Myeloid Cells.

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Mortha, Arthur; Burrows, Kyle

2018-01-01

Innate lymphoid cells (ILCs) are an essential component of the innate immune system in vertebrates. They are developmentally rooted in the lymphoid lineage and can diverge into at least three transcriptionally distinct lineages. ILCs seed both lymphoid and non-lymphoid tissues and are locally self-maintained in tissue-resident pools. Tissue-resident ILCs execute important effector functions making them key regulator in tissue homeostasis, repair, remodeling, microbial defense, and anti-tumor immunity. Similar to T lymphocytes, ILCs possess only few sensory elements for the recognition of non-self and thus depend on extrinsic cellular sensory elements residing within the tissue. Myeloid cells, including mononuclear phagocytes (MNPs), are key sentinels of the tissue and are able to translate environmental cues into an effector profile that instructs lymphocyte responses. The adaptation of myeloid cells to the tissue state thus influences the effector program of ILCs and serves as an example of how environmental signals are integrated into the function of ILCs via a tissue-resident immune cell cross talks. This review summarizes our current knowledge on the role of myeloid cells in regulating ILC functions and discusses how feedback communication between ILCs and myeloid cells contribute to stabilize immune homeostasis in order to maintain the healthy state of an organ.

HLA-DRB1*16-restricted recognition of myeloid cells, including CD34+ CML progenitor cells

NARCIS (Netherlands)

Ebeling, Saskia B.; Ivanov, Roman; Hol, Samantha; Aarts, Tineke I.; Hagenbeek, Anton; Verdonck, Leo F.; Petersen, Eefke J.

2003-01-01

The therapeutic effect of a human leucocyte antigen (HLA)-identical allogeneic stem cell transplantation (allo-SCT) for the treatment of haematological malignancies is mediated partly by the allogeneic T cells that are administered together with the stem cell graft. Chronic myeloid leukaemia (CML)

Isocitrate dehydrogenase 1 mutations prime the all-trans retinoic acid myeloid differentiation pathway in acute myeloid leukemia

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Boutzen, Héléna; Saland, Estelle; Larrue, Clément; de Toni, Fabienne; Gales, Lara; Castelli, Florence A.; Cathebas, Mathilde; Zaghdoudi, Sonia; Stuani, Lucille; Kaoma, Tony; Riscal, Romain; Yang, Guangli; Hirsch, Pierre; David, Marion; De Mas-Mansat, Véronique; Delabesse, Eric; Vallar, Laurent; Delhommeau, François; Jouanin, Isabelle; Ouerfelli, Ouathek; Le Cam, Laurent; Linares, Laetitia K.; Junot, Christophe; Portais, Jean-Charles; Vergez, François; Récher, Christian

2016-01-01

Acute myeloid leukemia (AML) is characterized by the accumulation of malignant blasts with impaired differentiation programs caused by recurrent mutations, such as the isocitrate dehydrogenase (IDH) mutations found in 15% of AML patients. These mutations result in the production of the oncometabolite (R)-2-hydroxyglutarate (2-HG), leading to a hypermethylation phenotype that dysregulates hematopoietic differentiation. In this study, we identified mutant R132H IDH1-specific gene signatures regulated by key transcription factors, particularly CEBPα, involved in myeloid differentiation and retinoid responsiveness. We show that treatment with all-trans retinoic acid (ATRA) at clinically achievable doses markedly enhanced terminal granulocytic differentiation in AML cell lines, primary patient samples, and a xenograft mouse model carrying mutant IDH1. Moreover, treatment with a cell-permeable form of 2-HG sensitized wild-type IDH1 AML cells to ATRA-induced myeloid differentiation, whereas inhibition of 2-HG production significantly reduced ATRA effects in mutant IDH1 cells. ATRA treatment specifically decreased cell viability and induced apoptosis of mutant IDH1 blasts in vitro. ATRA also reduced tumor burden of mutant IDH1 AML cells xenografted in NOD–Scid–IL2rγnull mice and markedly increased overall survival, revealing a potent antileukemic effect of ATRA in the presence of IDH1 mutation. This therapeutic strategy holds promise for this AML patient subgroup in future clinical studies. PMID:26951332

Enhancing Natural Killer Cell Mediated Targeting and Responses to Myeloid Leukemias

Science.gov (United States)

2017-10-01

AWARD NUMBER: W81XWH-16-1-0380 TITLE: Enhancing Natural Killer Cell Mediated Targeting and Responses to Myeloid Leukemias PRINCIPAL...2017 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Enhancing Natural Killer Cell Mediated Targeting and Responses to Myeloid Leukemias 5b. GRANT NUMBER...leukemias still have poor prognosis, particularly in the elderly, and require hematopoietic cell transplants to fully kill the tumor, which is both

History of myeloid-derived suppressor cells.

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Talmadge, James E; Gabrilovich, Dmitry I

2013-10-01

Tumour-induced granulocytic hyperplasia is associated with tumour vasculogenesis and escape from immunity via T cell suppression. Initially, these myeloid cells were identified as granulocytes or monocytes; however, recent studies have revealed that this hyperplasia is associated with populations of multipotent progenitor cells that have been identified as myeloid-derived suppressor cells (MDSCs). The study of MDSCs has provided a wealth of information regarding tumour pathobiology, has extended our understanding of neoplastic progression and has modified our approaches to immune adjuvant therapy. In this Timeline article, we discuss the history of MDSCs, their influence on tumour progression and metastasis, and the crosstalk between tumour cells, MDSCs and the host macroenvironment.

Mesenchymal Stem Cells (MSC Regulate Activation of Granulocyte-Like Myeloid Derived Suppressor Cells (G-MDSC in Chronic Myeloid Leukemia Patients.

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Cesarina Giallongo

Full Text Available It is well known that mesenchymal stem cells (MSC have a role in promotion of tumor growth, survival and drug-resistance in chronic myeloid leukemia (CML. Recent reports indicated that a subpopulation of myeloid cells, defined as granulocyte-like myeloid-derived suppressor cells (G-MDSC is increased in these patients. So far, the role of MSC in MDSC expansion and activation into the BM microenvironment remains unexplored. To address this question, here we use a specific experimental model in vitro, co-culturing MSC with peripheral blood mononucleated cells (PBMC from normal individuals, in order to generate MSC-educated G-MDSC. Although MSC of healthy donors (HD and CML patients were able to generate the same amount of MDSC, only CML-MSC-educated G-MDSC exhibited suppressive ability on autologous T lymphocytes. In addition, compared with HD-MSC, CML-MSC over-expressed some immunomodulatory factors including TGFβ, IL6 and IL10, that could be involved in MDSC activation. CML-MSC-educated G-MDSC expressed higher levels of ARG1, TNFα, IL1β, COX2 and IL6 than G-MDSC isolated from co-culture with HD-MSC. Our data provide evidence that CML-MSC may play a critical role in tumor microenvironment by orchestrating G-MDSC activation and regulating T lymphocytes-mediated leukemia surveillance, thus contributing to CML immune escape.

Mesenchymal Stem Cells (MSC) Regulate Activation of Granulocyte-Like Myeloid Derived Suppressor Cells (G-MDSC) in Chronic Myeloid Leukemia Patients.

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Giallongo, Cesarina; Romano, Alessandra; Parrinello, Nunziatina Laura; La Cava, Piera; Brundo, Maria Violetta; Bramanti, Vincenzo; Stagno, Fabio; Vigneri, Paolo; Chiarenza, Annalisa; Palumbo, Giuseppe Alberto; Tibullo, Daniele; Di Raimondo, Francesco

2016-01-01

It is well known that mesenchymal stem cells (MSC) have a role in promotion of tumor growth, survival and drug-resistance in chronic myeloid leukemia (CML). Recent reports indicated that a subpopulation of myeloid cells, defined as granulocyte-like myeloid-derived suppressor cells (G-MDSC) is increased in these patients. So far, the role of MSC in MDSC expansion and activation into the BM microenvironment remains unexplored. To address this question, here we use a specific experimental model in vitro, co-culturing MSC with peripheral blood mononucleated cells (PBMC) from normal individuals, in order to generate MSC-educated G-MDSC. Although MSC of healthy donors (HD) and CML patients were able to generate the same amount of MDSC, only CML-MSC-educated G-MDSC exhibited suppressive ability on autologous T lymphocytes. In addition, compared with HD-MSC, CML-MSC over-expressed some immunomodulatory factors including TGFβ, IL6 and IL10, that could be involved in MDSC activation. CML-MSC-educated G-MDSC expressed higher levels of ARG1, TNFα, IL1β, COX2 and IL6 than G-MDSC isolated from co-culture with HD-MSC. Our data provide evidence that CML-MSC may play a critical role in tumor microenvironment by orchestrating G-MDSC activation and regulating T lymphocytes-mediated leukemia surveillance, thus contributing to CML immune escape.

Evolution of our understanding of myeloid regulatory cells: from MDSCs to Mregs

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Masoud H Manjili

2014-07-01

Full Text Available The term Myeloid-Derived Suppressor Cells (MDSCs was first suggested in 2007 in order to reflect on the origin and function of myeloid cells during immunosuppression in cancer and other pathologic conditions. Emerging evidence suggest that MDSCs suppress CTL and Th1 responses in malignant diseases while they regulate effective immune responses in parasitic and helminth infections as well as Th17 inflammatory response during autoimmune diseases. Based on these data the term myeloid regulatory cells (Mregs more accurately reflects their function and interactions with different cells of the immune system during diseased conditions. Here, we provide evidence on the multifaceted function of Mregs during diseased states.

Identification of Reprogrammed Myeloid Cell Transcriptomes in NSCLC.

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Anna Durrans

Full Text Available Lung cancer is the leading cause of cancer related mortality worldwide, with non-small cell lung cancer (NSCLC as the most prevalent form. Despite advances in treatment options including minimally invasive surgery, CT-guided radiation, novel chemotherapeutic regimens, and targeted therapeutics, prognosis remains dismal. Therefore, further molecular analysis of NSCLC is necessary to identify novel molecular targets that impact prognosis and the design of new-targeted therapies. In recent years, tumor "activated/reprogrammed" stromal cells that promote carcinogenesis have emerged as potential therapeutic targets. However, the contribution of stromal cells to NSCLC is poorly understood. Here, we show increased numbers of bone marrow (BM-derived hematopoietic cells in the tumor parenchyma of NSCLC patients compared with matched adjacent non-neoplastic lung tissue. By sorting specific cellular fractions from lung cancer patients, we compared the transcriptomes of intratumoral myeloid compartments within the tumor bed with their counterparts within adjacent non-neoplastic tissue from NSCLC patients. The RNA sequencing of specific myeloid compartments (immature monocytic myeloid cells and polymorphonuclear neutrophils identified differentially regulated genes and mRNA isoforms, which were inconspicuous in whole tumor analysis. Genes encoding secreted factors, including osteopontin (OPN, chemokine (C-C motif ligand 7 (CCL7 and thrombospondin 1 (TSP1 were identified, which enhanced tumorigenic properties of lung cancer cells indicative of their potential as targets for therapy. This study demonstrates that analysis of homogeneous stromal populations isolated directly from fresh clinical specimens can detect important stromal genes of therapeutic value.

Canthin-6-one induces cell death, cell cycle arrest and differentiation in human myeloid leukemia cells.

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Vieira Torquato, Heron F; Ribeiro-Filho, Antonio C; Buri, Marcus V; Araújo Júnior, Roberto T; Pimenta, Renata; de Oliveira, José Salvador R; Filho, Valdir C; Macho, Antonio; Paredes-Gamero, Edgar J; de Oliveira Martins, Domingos T

2017-04-01

Canthin-6-one is a natural product isolated from various plant genera and from fungi with potential antitumor activity. In the present study, we evaluate the antitumor effects of canthin-6-one in human myeloid leukemia lineages. Kasumi-1 lineage was used as a model for acute myeloid leukemia. Cells were treated with canthin-6-one and cell death, cell cycle and differentiation were evaluated in both total cells (Lin + ) and leukemia stem cell population (CD34 + CD38 - Lin -/low ). Among the human lineages tested, Kasumi-1 was the most sensitive to canthin-6-one. Canthin-6-one induced cell death with apoptotic (caspase activation, decrease of mitochondrial potential) and necrotic (lysosomal permeabilization, double labeling of annexin V/propidium iodide) characteristics. Moreover, canthin-6-one induced cell cycle arrest at G 0 /G 1 (7μM) and G 2 (45μM) evidenced by DNA content, BrdU incorporation and cyclin B1/histone 3 quantification. Canthin-6-one also promoted differentiation of Kasumi-1, evidenced by an increase in the expression of myeloid markers (CD11b and CD15) and the transcription factor PU.1. Furthermore, a reduction of the leukemic stem cell population and clonogenic capability of stem cells were observed. These results show that canthin-6-one can affect Kasumi-1 cells by promoting cell death, cell cycle arrest and cell differentiation depending on concentration used. Canthin-6-one presents an interesting cytotoxic activity against leukemic cells and represents a promising scaffold for the development of molecules for anti-leukemic applications, especially by its anti-leukemic stem cell activity. Copyright © 2017 Elsevier B.V. All rights reserved.

Dynamics of myeloid cell populations during relapse-preventive immunotherapy in acute myeloid leukemia.

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Rydström, Anna; Hallner, Alexander; Aurelius, Johan; Sander, Frida Ewald; Bernson, Elin; Kiffin, Roberta; Thoren, Fredrik Bergh; Hellstrand, Kristoffer; Martner, Anna

2017-08-01

Relapse of leukemia in the postchemotherapy phase contributes to the poor prognosis and survival in patients with acute myeloid leukemia (AML). In an international phase IV trial (ClinicalTrials.gov; NCT01347996), 84 patients with AML in first complete remission who had not undergone transplantation received immunotherapy with histamine dihydrochloride (HDC) and low-dose IL-2 with the aim of preventing relapse. The dynamics of myeloid cell counts and expression of activation markers was assessed before and after cycles of immunotherapy and correlated with clinical outcome in terms of relapse risk and survival. During cycles, a pronounced increase in blood eosinophil counts was observed along with a reduction in monocyte and neutrophil counts. A strong reduction of blood monocyte counts during the first HDC/IL-2 treatment cycle predicted leukemia-free survival. The HDC component of the immunotherapy exerts agonist activity at histamine type 2 receptors (H2Rs) that are expressed by myeloid cells. It was observed that the density of H 2 R expression in blood monocytes increased during cycles of immunotherapy and that high monocyte H 2 R expression implied reduced relapse risk and improved overall survival. Several other activation markers, including HLA-DR, CD86, and CD40, were induced in monocytes and dendritic cells during immunotherapy but did not predict clinical outcome. In addition, expression of HLA-ABC increased in all myeloid populations during therapy. A low expression of HLA-ABC was associated with reduced relapse risk. These results suggest that aspects of myeloid cell biology may impact clinical benefit of relapse-preventive immunotherapy in AML. © Society for Leukocyte Biology.

Global Identification of EVI1 Target Genes in Acute Myeloid Leukemia.

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Carolyn Glass

Full Text Available The ecotropic virus integration site 1 (EVI1 transcription factor is associated with human myeloid malignancy of poor prognosis and is overexpressed in 8-10% of adult AML and strikingly up to 27% of pediatric MLL-rearranged leukemias. For the first time, we report comprehensive genomewide EVI1 binding and whole transcriptome gene deregulation in leukemic cells using a combination of ChIP-Seq and RNA-Seq expression profiling. We found disruption of terminal myeloid differentiation and cell cycle regulation to be prominent in EVI-induced leukemogenesis. Specifically, we identified EVI1 directly binds to and downregulates the master myeloid differentiation gene Cebpe and several of its downstream gene targets critical for terminal myeloid differentiation. We also found EVI1 binds to and downregulates Serpinb2 as well as numerous genes involved in the Jak-Stat signaling pathway. Finally, we identified decreased expression of several ATP-dependent P2X purinoreceptors genes involved in apoptosis mechanisms. These findings provide a foundation for future study of potential therapeutic gene targets for EVI1-induced leukemia.

Tissue type plasminogen activator regulates myeloid-cell dependent neoangiogenesis during tissue regeneration

DEFF Research Database (Denmark)

Ohki, Makiko; Ohki, Yuichi; Ishihara, Makoto

2010-01-01

tissue regeneration is not well understood. Bone marrow (BM)-derived myeloid cells facilitate angiogenesis during tissue regeneration. Here, we report that a serpin-resistant form of tPA by activating the extracellular proteases matrix metalloproteinase-9 and plasmin expands the myeloid cell pool......-A. Remarkably, transplantation of BM-derived tPA-mobilized CD11b(+) cells and VEGFR-1(+) cells, but not carrier-mobilized cells or CD11b(-) cells, accelerates neovascularization and ischemic tissue regeneration. Inhibition of VEGF signaling suppresses tPA-induced neovascularization in a model of hind limb...... and mobilizes CD45(+)CD11b(+) proangiogenic, myeloid cells, a process dependent on vascular endothelial growth factor-A (VEGF-A) and Kit ligand signaling. tPA improves the incorporation of CD11b(+) cells into ischemic tissues and increases expression of neoangiogenesis-related genes, including VEGF...

Tunneling Nanotubes: Intimate Communication between Myeloid Cells.

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Dupont, Maeva; Souriant, Shanti; Lugo-Villarino, Geanncarlo; Maridonneau-Parini, Isabelle; Vérollet, Christel

2018-01-01

Tunneling nanotubes (TNT) are dynamic connections between cells, which represent a novel route for cell-to-cell communication. A growing body of evidence points TNT towards a role for intercellular exchanges of signals, molecules, organelles, and pathogens, involving them in a diverse array of functions. TNT form among several cell types, including neuronal cells, epithelial cells, and almost all immune cells. In myeloid cells (e.g., macrophages, dendritic cells, and osteoclasts), intercellular communication via TNT contributes to their differentiation and immune functions. Importantly, TNT enable myeloid cells to communicate with a targeted neighboring or distant cell, as well as with other cell types, therefore creating a complex variety of cellular exchanges. TNT also contribute to pathogen spread as they serve as "corridors" from a cell to another. Herein, we addressed the complexity of the definition and in vitro characterization of TNT in innate immune cells, the different processes involved in their formation, and their relevance in vivo . We also assess our current understanding of how TNT participate in immune surveillance and the spread of pathogens, with a particular interest for HIV-1. Overall, despite recent progress in this growing research field, we highlight that further investigation is needed to better unveil the role of TNT in both physiological and pathological conditions.

Tunneling Nanotubes: Intimate Communication between Myeloid Cells

Directory of Open Access Journals (Sweden)

Maeva Dupont

2018-01-01

Full Text Available Tunneling nanotubes (TNT are dynamic connections between cells, which represent a novel route for cell-to-cell communication. A growing body of evidence points TNT towards a role for intercellular exchanges of signals, molecules, organelles, and pathogens, involving them in a diverse array of functions. TNT form among several cell types, including neuronal cells, epithelial cells, and almost all immune cells. In myeloid cells (e.g., macrophages, dendritic cells, and osteoclasts, intercellular communication via TNT contributes to their differentiation and immune functions. Importantly, TNT enable myeloid cells to communicate with a targeted neighboring or distant cell, as well as with other cell types, therefore creating a complex variety of cellular exchanges. TNT also contribute to pathogen spread as they serve as “corridors” from a cell to another. Herein, we addressed the complexity of the definition and in vitro characterization of TNT in innate immune cells, the different processes involved in their formation, and their relevance in vivo. We also assess our current understanding of how TNT participate in immune surveillance and the spread of pathogens, with a particular interest for HIV-1. Overall, despite recent progress in this growing research field, we highlight that further investigation is needed to better unveil the role of TNT in both physiological and pathological conditions.

Radiation response of mouse lymphoid and myeloid cell lines. Pt. 1

International Nuclear Information System (INIS)

Radford, I.R.

1994-01-01

The sensitivity of 10 mouse lymphoid or myeloid cell lines to γ-ray- and DNA-associated 125 I-decay-induced clonogenic cell killing have been compared with their rate of loss of viability (membrane integrity) and with their putative cell type of origin. The increased sensitivity of haematopoietic cell lines to killing by DNA dsb may be related to their mode of death (apoptosis versus necrosis). Mode of cell death may thus be an important factor in determining the 'inherent radiosensitivity' of normal cells/tissues. Haematopoietic cell lines that undergo rapid interphase apoptotic death showed extreme sensitivity to DNA dsb. (author)

Macrophage colony-stimulating factor receptor marks and regulates a fetal myeloid-primed B-cell progenitor in mice.

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Zriwil, Alya; Böiers, Charlotta; Wittmann, Lilian; Green, Joanna C A; Woll, Petter S; Jacobsen, Sten Eirik W; Sitnicka, Ewa

2016-07-14

Although it is well established that unique B-cell lineages develop through distinct regulatory mechanisms during embryonic development, much less is understood about the differences between embryonic and adult B-cell progenitor cells, likely to underpin the genetics and biology of infant and childhood PreB acute lymphoblastic leukemia (PreB-ALL), initiated by distinct leukemia-initiating translocations during embryonic development. Herein, we establish that a distinct subset of the earliest CD19(+) B-cell progenitors emerging in the E13.5 mouse fetal liver express the colony-stimulating factor-1 receptor (CSF1R), previously thought to be expressed, and play a lineage-restricted role in development of myeloid lineages, and macrophages in particular. These early embryonic CSF1R(+)CD19(+) ProB cells also express multiple other myeloid genes and, in line with this, possess residual myeloid as well as B-cell, but not T-cell lineage potential. Notably, these CSF1R(+) myeloid-primed ProB cells are uniquely present in a narrow window of embryonic fetal liver hematopoiesis and do not persist in adult bone marrow. Moreover, analysis of CSF1R-deficient mice establishes a distinct role of CSF1R in fetal B-lymphopoiesis. CSF1R(+) myeloid-primed embryonic ProB cells are relevant for infant and childhood PreB-ALLs, which frequently have a bi-phenotypic B-myeloid phenotype, and in which CSF1R-rearrangements have recently been reported. © 2016 by The American Society of Hematology.

Tissue factor expression by myeloid cells contributes to protective immune response against Mycobacterium tuberculosis infection.

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Venkatasubramanian, Sambasivan; Tripathi, Deepak; Tucker, Torry; Paidipally, Padmaja; Cheekatla, Satyanarayana; Welch, Elwyn; Raghunath, Anjana; Jeffers, Ann; Tvinnereim, Amy R; Schechter, Melissa E; Andrade, Bruno B; Mackman, Nizel; Idell, Steven; Vankayalapati, Ramakrishna

2016-02-01

Tissue factor (TF) is a transmembrane glycoprotein that plays an essential role in hemostasis by activating coagulation. TF is also expressed by monocytes/macrophages as part of the innate immune response to infections. In the current study, we determined the role of TF expressed by myeloid cells during Mycobacterium tuberculosis (M. tb) infection by using mice lacking the TF gene in myeloid cells (TF(Δ) ) and human monocyte derived macrophages (MDMs). We found that during M. tb infection, a deficiency of TF in myeloid cells was associated with reduced inducible nitric oxide synthase (iNOS) expression, enhanced arginase 1 (Arg1) expression, enhanced IL-10 production and reduced apoptosis in infected macrophages, which augmented M. tb growth. Our results demonstrate that a deficiency of TF in myeloid cells promotes M2-like phenotype in M .tb infected macrophages. A deficiency in TF expression by myeloid cells was also associated with reduced fibrin deposition and increased matrix metalloproteases (MMP)-2 and MMP-9 mediated inflammation in M. tb infected lungs. Our studies demonstrate that TF expressed by myeloid cells has newly recognized abilities to polarize macrophages and to regulate M. tb growth. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Mesenchymal Stem Cells Modulate Differentiation of Myeloid Progenitor Cells During Inflammation.

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Amouzegar, Afsaneh; Mittal, Sharad K; Sahu, Anuradha; Sahu, Srikant K; Chauhan, Sunil K

2017-06-01

Mesenchymal stem cells (MSCs) possess distinct immunomodulatory properties and have tremendous potential for use in therapeutic applications in various inflammatory diseases. MSCs have been shown to regulate pathogenic functions of mature myeloid inflammatory cells, such as macrophages and neutrophils. Intriguingly, the capacity of MSCs to modulate differentiation of myeloid progenitors (MPs) to mature inflammatory cells remains unknown to date. Here, we report the novel finding that MSCs inhibit the expression of differentiation markers on MPs under inflammatory conditions. We demonstrate that the inhibitory effect of MSCs is dependent on direct cell-cell contact and that this intercellular contact is mediated through interaction of CD200 expressed by MSCs and CD200R1 expressed by MPs. Furthermore, using an injury model of sterile inflammation, we show that MSCs promote MP frequencies and suppress infiltration of inflammatory cells in the inflamed tissue. We also find that downregulation of CD200 in MSCs correlates with abrogation of their immunoregulatory function. Collectively, our study provides unequivocal evidence that MSCs inhibit differentiation of MPs in the inflammatory environment via CD200-CD200R1 interaction. Stem Cells 2017;35:1532-1541. © 2017 AlphaMed Press.

Control of Both Myeloid Cell Infiltration and Angiogenesis by CCR1 Promotes Liver Cancer Metastasis Development in Mice

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Mathieu Paul Rodero

2013-06-01

Full Text Available Expression of the CC chemokine receptor 1 (CCR1 by tumor cells has been associated with protumoral activity; however, its role in nontumoral cells during tumor development remains elusive. Here, we investigated the role of CCR1 deletion on stromal and hematopoietic cells in a liver metastasis tumor model. Metastasis development was strongly impaired in CCR1-deficient mice compared to control mice and was associated with reduced liver monocyte infiltration. To decipher the role of myeloid cells, sublethally irradiated mice were reconstituted with CCR1-deficient bone marrow (BM and showed better survival rates than the control reconstituted mice. These results point toward the involvement of CCR1 myeloid cell infiltration in the promotion of tumor burden. In addition, survival rates were extended in CCR1-deficient mice receiving either control or CCR1-deficient BM, indicating that host CCR1 expression on nonhematopoietic cells also supports tumor growth. Finally, we found defective tumor-induced neoangiogenesis (in vitro and in vivo in CCR1-deficient mice. Overall, our results indicate that CCR1 expression by both hematopoietic and nonhematopoietic cells favors tumor aggressiveness. We propose CCR1 as a potential therapeutical target for liver metastasis therapy.

Targeting Human C-Type Lectin-Like Molecule-1 (CLL1) with a Bispecific Antibody for Acute Myeloid Leukemia Immunotherapy**

OpenAIRE

Lu, Hua; Zhou, Quan; Deshmukh, Vishal; Phull, Hardeep; Ma, Jennifer; Tardif, Virginie; Naik, Rahul R.; Bouvard, Claire; Zhang, Yong; Choi, Seihyun; Lawson, Brian R.; Zhu, Shoutian; Kim, Chan Hyuk; Schultz, Peter G.

2014-01-01

Acute myeloid leukemia (AML), the most common acute adult leukemia and the second most common pediatric leukemia, still has a poor prognosis. Human C-type lectin-like molecule-1 (CLL1) is a recently identified myeloid lineage restricted cell surface marker, which is overexpressed in over 90% of AML patient myeloid blasts and in leukemic stem cells. Here, we describe the synthesis of a novel bispecific antibody, αCLL1-αCD3, using the genetically encoded unnatural amino acid, p-acetylphenylalan...

Myeloid-derived suppressor cells in breast cancer.

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Markowitz, Joseph; Wesolowski, Robert; Papenfuss, Tracey; Brooks, Taylor R; Carson, William E

2013-07-01

Myeloid-derived suppressor cells (MDSCs) are a population of immature myeloid cells defined by their suppressive actions on immune cells such as T cells, dendritic cells, and natural killer cells. MDSCs typically are positive for the markers CD33 and CD11b but express low levels of HLADR in humans. In mice, MDSCs are typically positive for both CD11b and Gr1. These cells exert their suppressive activity on the immune system via the production of reactive oxygen species, arginase, and cytokines. These factors subsequently inhibit the activity of multiple protein targets such as the T cell receptor, STAT1, and indoleamine-pyrrole 2,3-dioxygenase. The numbers of MDSCs tend to increase with cancer burden while inhibiting MDSCs improves disease outcome in murine models. MDSCs also inhibit immune cancer therapeutics. In light of the poor prognosis of metastatic breast cancer in women and the correlation of increasing levels of MDSCs with increasing disease burden, the purposes of this review are to (1) discuss why MDSCs may be important in breast cancer, (2) describe model systems used to study MDSCs in vitro and in vivo, (3) discuss mechanisms involved in MDSC induction/function in breast cancer, and (4) present pre-clinical and clinical studies that explore modulation of the MDSC-immune system interaction in breast cancer. MDSCs inhibit the host immune response in breast cancer patients and diminishing MDSC actions may improve therapeutic outcomes.

Direct conversion of injury-site myeloid cells to fibroblast-like cells of granulation tissue.

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Sinha, Mithun; Sen, Chandan K; Singh, Kanhaiya; Das, Amitava; Ghatak, Subhadip; Rhea, Brian; Blackstone, Britani; Powell, Heather M; Khanna, Savita; Roy, Sashwati

2018-03-05

Inflammation, following injury, induces cellular plasticity as an inherent component of physiological tissue repair. The dominant fate of wound macrophages is unclear and debated. Here we show that two-thirds of all granulation tissue fibroblasts, otherwise known to be of mesenchymal origin, are derived from myeloid cells which are likely to be wound macrophages. Conversion of myeloid to fibroblast-like cells is impaired in diabetic wounds. In cross-talk between keratinocytes and myeloid cells, miR-21 packaged in extracellular vesicles (EV) is required for cell conversion. EV from wound fluid of healing chronic wound patients is rich in miR-21 and causes cell conversion more effectively compared to that by fluid from non-healing patients. Impaired conversion in diabetic wound tissue is rescued by targeted nanoparticle-based delivery of miR-21 to macrophages. This work introduces a paradigm wherein myeloid cells are recognized as a major source of fibroblast-like cells in the granulation tissue.

Myeloid-Derived Suppressor Cells and Therapeutic Strategies in Cancer

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Hiroshi Katoh

2015-01-01

Full Text Available Development of solid cancer depends on escape from host immunosurveillance. Various types of immune cells contribute to tumor-induced immune suppression, including tumor associated macrophages, regulatory T cells, type 2 NKT cells, and myeloid-derived suppressor cells (MDSCs. Growing body of evidences shows that MDSCs play pivotal roles among these immunosuppressive cells in multiple steps of cancer progression. MDSCs are immature myeloid cells that arise from myeloid progenitor cells and comprise a heterogeneous immune cell population. MDSCs are characterized by the ability to suppress both adaptive and innate immunities mainly through direct inhibition of the cytotoxic functions of T cells and NK cells. In clinical settings, the number of circulating MDSCs is associated with clinical stages and response to treatment in several cancers. Moreover, MDSCs are reported to contribute to chemoresistant phenotype. Collectively, targeting MDSCs could potentially provide a rationale for novel treatment strategies in cancer. This review summarizes recent understandings of MDSCs in cancer and discusses promissing clinical approaches in cancer patients.

Rethinking the role of myeloid-derived suppressor cells in adoptive T-cell therapy for cancer

Science.gov (United States)

Arina, Ainhoa

2014-01-01

The expansion of cancer-induced myeloid cells is thought to be one of the main obstacles to successful immunotherapy. Nevertheless, in murine tumors undergoing immune-mediated destruction by adoptively transferred T cells, we have recently shown that such cells maintain their immunosuppressive properties. Therefore, adoptive T-cell therapy can, under certain conditions, overcome myeloid cell immunosuppression. PMID:25050213

The zebrafish spi1 promoter drives myeloid-specific expression in stable transgenic fish

NARCIS (Netherlands)

Ward, AC; McPhee, DO; Condron, MM; Varma, S; Cody, SH; Onnebo, SMN; Paw, BH; Zon, LI; Lieschke, GJ

2003-01-01

The spi1 (pu.1) gene has recently been identified as a useful marker of early myeloid cells in zebrafish. To enhance the versatility of this organism as a model for studying myeloid development, the promoter of this gene has been isolated and characterized. Transient transgenesis revealed that a 5.3

Generation of Human Immunosuppressive Myeloid Cell Populations in Human Interleukin-6 Transgenic NOG Mice

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Asami Hanazawa

2018-02-01

Full Text Available The tumor microenvironment contains unique immune cells, termed myeloid-derived suppressor cells (MDSCs, and tumor-associated macrophages (TAMs that suppress host anti-tumor immunity and promote tumor angiogenesis and metastasis. Although these cells are considered a key target of cancer immune therapy, in vivo animal models allowing differentiation of human immunosuppressive myeloid cells have yet to be established, hampering the development of novel cancer therapies. In this study, we established a novel humanized transgenic (Tg mouse strain, human interleukin (hIL-6-expressing NOG mice (NOG-hIL-6 transgenic mice. After transplantation of human hematopoietic stem cells (HSCs, the HSC-transplanted NOG-hIL-6 Tg mice (HSC-NOG-hIL-6 Tg mice showed enhanced human monocyte/macrophage differentiation. A significant number of human monocytes were negative for HLA-DR expression and resembled immature myeloid cells in the spleen and peripheral blood from HSC-NOG-hIL-6 Tg mice, but not from HSC-NOG non-Tg mice. Engraftment of HSC4 cells, a human head and neck squamous cell carcinoma-derived cell line producing various factors including IL-6, IL-1β, macrophage colony-stimulating factor (M-CSF, and vascular endothelial growth factor (VEGF, into HSC-NOG-hIL-6 Tg mice induced a significant number of TAM-like cells, but few were induced in HSC-NOG non-Tg mice. The tumor-infiltrating macrophages in HSC-NOG-hIL-6 Tg mice expressed a high level of CD163, a marker of immunoregulatory myeloid cells, and produced immunosuppressive molecules such as arginase-1 (Arg-1, IL-10, and VEGF. Such cells from HSC-NOG-hIL-6 Tg mice, but not HSC-NOG non-Tg mice, suppressed human T cell proliferation in response to antigen stimulation in in vitro cultures. These results suggest that functional human TAMs can be developed in NOG-hIL-6 Tg mice. This mouse model will contribute to the development of novel cancer immune therapies targeting immunoregulatory

Porphyromonas gingivalis regulates TREM-1 in human polymorphonuclear neutrophils via its gingipains.

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Nagihan Bostanci

Full Text Available The Triggering Receptor Expressed on Myeloid cells 1 (TREM-1 is a cell surface receptor of the immunoglobulin superfamily, with the capacity to amplify pro-inflammatory cytokine production and regulate apoptosis. Polymorphonuclear neutrophils (PMNs are the first line of defence against infection, and a major source of TREM-1. Porphyromonas gingivalis is a Gram-negative anaerobe highly implicated in the inflammatory processes governing periodontal disease, which is characterized by the destruction of the tooth-supporting tissues. It expresses a number of virulence factors, including the cysteine proteinases (or gingipains. The aim of this in vitro study was to investigate the effect of P. gingivalis on TREM-1 expression and production by primary human PMNs, and to evaluate the role of its gingipains in this process. After 4 h of challenge, P. gingivalis enhanced TREM-1 expression as identified by quantitative real-time PCR. This was followed by an increase in soluble (sTREM-1 secretion over a period of 18 h, as determined by ELISA. At this time-point, the P. gingivalis-challenged PMNs exhibited diminished TREM-1 cell-membrane staining, as identified by flow cytometry and confocal laser scanning microscopy. Furthermore engagement of TREM-1, by means of anti-TREM-1 antibodies, enhanced the capacity of P. gingivalis to stimulate interleukin (IL-8 production. Conversely, antagonism of TREM-1 using a synthetic peptide resulted in reduction of IL-8 secretion. Using isogenic P. gingivalis mutant strains, we identified the Arg-gingipain to be responsible for shedding of sTREM-1 from the PMN surface, whereas the Lys-gingipain had the capacity to degrade TREM-1. In conclusion, the differential regulation of TREM-1 by the P. gingivalis gingipains may present a novel mechanism by which P. gingivalis manipulates the host innate immune response helping to establish chronic periodontal inflammation.

Monocytic myeloid-derived suppressor cells as prognostic factor in chronic myeloid leukaemia patients treated with dasatinib.

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Giallongo, Cesarina; Parrinello, Nunziatina L; La Cava, Piera; Camiolo, Giuseppina; Romano, Alessandra; Scalia, Marina; Stagno, Fabio; Palumbo, Giuseppe A; Avola, Roberto; Li Volti, Giovanni; Tibullo, Daniele; Di Raimondo, Francesco

2018-02-01

Myeloid suppressor cells are a heterogeneous group of myeloid cells that are increased in patients with chronic myeloid leukaemia (CML) inducing T cell tolerance. In this study, we found that therapy with tyrosine kinase inhibitors (TKI) decreased the percentage of granulocytic MDSC, but only patients treated with dasatinib showed a significant reduction in the monocytic subset (M-MDSC). Moreover, a positive correlation was observed between number of persistent M-MDSC and the value of major molecular response in dasatinib-treated patients. Serum and exosomes from patients with CML induced conversion of monocytes from healthy volunteers into immunosuppressive M-MDSC, suggesting a bidirectional crosstalk between CML cells and MDSC. Overall, we identified M-MDSC as prognostic factors in patients treated with dasatinib. It might be of interest to understand whether MDSC may be a candidate predictive markers of relapse risk following TKI discontinuation, suggesting their potential significance as practice of precision medicine. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

Leukomogenic factors downregulate heparanase expression in acute myeloid leukemia cells

International Nuclear Information System (INIS)

Eshel, Rinat; Ben-Zaken, Olga; Vainas, Oded; Nadir, Yona; Minucci, Saverio; Polliack, Aaron; Naparstek, Ella; Vlodavsky, Israel; Katz, Ben-Zion

2005-01-01

Heparanase is a heparan sulfate-degrading endoglycosidase expressed by mature monocytes and myeloid cells, but not by immature hematopoietic progenitors. Heparanase gene expression is upregulated during differentiation of immature myeloid cells. PML-RARα and PLZF-RARα fusion gene products associated with acute promyelocytic leukemia abrogate myeloid differentiation and heparanase expression. AML-Eto, a translocation product associated with AML FAB M2, also downregulates heparanase gene expression. The common mechanism that underlines the activity of these three fusion gene products involves the recruitment of histone deacetylase complexes to specific locations within the DNA. We found that retinoic acid that dissociates PML-RARα from the DNA, and which is used to treat acute promyelocytic leukemia patients, restores heparanase expression to normal levels in an acute promyelocytic leukemia cell line. The retinoic acid effects were also observed in primary acute promyelocytic leukemia cells and in a retinoic acid-treated acute promyelocytic leukemia patient. Histone deacetylase inhibitor reverses the downregulation of heparanase expression induced by the AML-Eto fusion gene product in M2 type AML. In summary, we have characterized a link between leukomogenic factors and the downregulation of heparanase in myeloid leukemic cells

Differential contribution of complement receptor C5aR in myeloid and non-myeloid cells in chronic ethanol-induced liver injury in mice.

Science.gov (United States)

McCullough, Rebecca L; McMullen, Megan R; Das, Dola; Roychowdhury, Sanjoy; Strainic, Michael G; Medof, M Edward; Nagy, Laura E

2016-07-01

Complement is implicated in the development of alcoholic liver disease. C3 and C5 contribute to ethanol-induced liver injury; however, the role of C5a receptor (C5aR) on myeloid and non-myeloid cells to progression of injury is not known. C57BL/6 (WT), global C5aR-/-, myeloid-specific C5aR-/-, and non-myeloid-specific C5aR-/- mice were fed a Lieber-DeCarli diet (32%kcal EtOH) for 25 days. Cultured hepatocytes were challenged with ethanol, TNFα, and C5a. Chronic ethanol feeding increased expression of pro-inflammatory mediators in livers of WT mice; this response was completely blunted in C5aR-/- mice. However, C5aR-/- mice were not protected from other measures of hepatocellular damage, including ethanol-induced increases in hepatic triglycerides, plasma alanine aminotransferase and hepatocyte apoptosis. CYP2E1 and 4-hydroxynonenal protein adducts were induced in WT and C5aR-/- mice. Myeloid-specific C5aR-/- mice were protected from ethanol-induced increases in hepatic TNFα, whereas non-myeloid-specific C5aR-/- displayed increased hepatocyte apoptosis and inflammation after chronic ethanol feeding. In cultured hepatocytes, cytotoxicity induced by challenge with ethanol and TNFα was completely eliminated by treatment with C5a in cells from WT, but not C5aR-/- mice. Further, treatment with C5a enhanced activation of pro-survival signal AKT in hepatocytes challenged with ethanol and TNFα. Taken together, these data reveal a differential role for C5aR during ethanol-induced liver inflammation and injury, with C5aR on myeloid cells contributing to ethanol-induced inflammatory cytokine expression, while non-myeloid C5aR protects hepatocytes from death after chronic ethanol feeding. Copyright © 2016 Elsevier Ltd. All rights reserved.

A drug development perspective on targeting tumor-associated myeloid cells.

Science.gov (United States)

Majety, Meher; Runza, Valeria; Lehmann, Christian; Hoves, Sabine; Ries, Carola H

2018-02-01

Despite decades of research, cancer remains a devastating disease and new treatment options are needed. Today cancer is acknowledged as a multifactorial disease not only comprising of aberrant tumor cells but also the associated stroma including tumor vasculature, fibrotic plaques, and immune cells that interact in a complex heterotypic interplay. Myeloid cells represent one of the most abundant immune cell population within the tumor stroma and are equipped with a broad functional repertoire that promotes tumor growth by suppressing cytotoxic T cell activity, stimulating neoangiogenesis and tissue remodeling. Therefore, myeloid cells have become an attractive target for pharmacological intervention. In this review, we summarize the pharmacological approaches to therapeutically target tumor-associated myeloid cells with a focus on advanced programs that are clinically evaluated. In addition, for each therapeutic strategy, the preclinical rationale as well as advantages and challenges from a drug development perspective are discussed. © 2017 Federation of European Biochemical Societies.

Myeloid cells in circulation and tumor microenvironment of breast cancer patients.

Science.gov (United States)

Toor, Salman M; Syed Khaja, Azharuddin Sajid; El Salhat, Haytham; Faour, Issam; Kanbar, Jihad; Quadri, Asif A; Albashir, Mohamed; Elkord, Eyad

2017-06-01

Pathological conditions including cancers lead to accumulation of a morphological mixture of highly immunosuppressive cells termed as myeloid-derived suppressor cells (MDSC). The lack of conclusive markers to identify human MDSC, due to their heterogeneous nature and close phenotypical and functional proximity with other cell subsets, made it challenging to identify these cells. Nevertheless, expansion of MDSC has been reported in periphery and tumor microenvironment of various cancers. The majority of studies on breast cancers were performed on murine models and hence limited literature is available on the relation of MDSC accumulation with clinical settings in breast cancer patients. The aim of this study was to investigate levels and phenotypes of myeloid cells in peripheral blood (n = 23) and tumor microenvironment of primary breast cancer patients (n = 7), compared with blood from healthy donors (n = 21) and paired non-tumor normal breast tissues from the same patients (n = 7). Using multicolor flow cytometric assays, we found that breast cancer patients had significantly higher levels of tumor-infiltrating myeloid cells, which comprised of granulocytes (P = 0.022) and immature cells that lack the expression of markers for fully differentiated monocytes or granulocytes (P = 0.016). Importantly, this expansion was not reflected in the peripheral blood. The immunosuppressive potential of these cells was confirmed by expression of Arginase 1 (ARG1), which is pivotal for T-cell suppression. These findings are important for developing therapeutic modalities to target mechanisms employed by immunosuppressive cells that generate an immune-permissive environment for the progression of cancer.

Myeloid derived suppressor cells (MDSCs are increased and exert immunosuppressive activity together with polymorphonuclear leukocytes (PMNs in chronic myeloid leukemia patients.

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Cesarina Giallongo

Full Text Available Tumor immune tolerance can derive from the recruitment of suppressor cell population, including myeloid derived suppressor cells (MDSCs, able to inhibit T cells activity. We identified a significantly expanded MDSCs population in chronic myeloid leukemia (CML patients at diagnosis that decreased to normal levels after imatinib therapy. In addition, expression of arginase 1 (Arg1 that depletes microenvironment of arginine, an essential aminoacid for T cell function, resulted in an increase in patients at diagnosis. Purified CML CD11b+CD33+CD14-HLADR- cells markedly suppressed normal donor T cell proliferation in vitro. Comparing CML Gr-MDSCs to autologous polymorphonuclear leukocytes (PMNs we observed a higher Arg1 expression and activity in PMNs, together with an inhibitory effect on T cells in vitro. Our data indicate that CML cells create an immuno-tolerant environment associated to MDSCs expansion with immunosuppressive capacity mediated by Arg1. In addition, we demonstrated for the first time also an immunosuppressive activity of CML PMNs, suggesting a strong potential immune escape mechanism created by CML cells, which control the anti-tumor reactive T cells. MDSCs should be monitored in imatinib discontinuation trials to understand their importance in relapsing patients.

IKKα Promotes Intestinal Tumorigenesis by Limiting Recruitment of M1-like Polarized Myeloid Cells

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Serkan I. Göktuna

2014-06-01

Full Text Available The recruitment of immune cells into solid tumors is an essential prerequisite of tumor development. Depending on the prevailing polarization profile of these infiltrating leucocytes, tumorigenesis is either promoted or blocked. Here, we identify IκB kinase α (IKKα as a central regulator of a tumoricidal microenvironment during intestinal carcinogenesis. Mice deficient in IKKα kinase activity are largely protected from intestinal tumor development that is dependent on the enhanced recruitment of interferon γ (IFNγ-expressing M1-like myeloid cells. In IKKα mutant mice, M1-like polarization is not controlled in a cell-autonomous manner but, rather, depends on the interplay of both IKKα mutant tumor epithelia and immune cells. Because therapies aiming at the tumor microenvironment rather than directly at the mutated cancer cell may circumvent resistance development, we suggest IKKα as a promising target for colorectal cancer (CRC therapy.

Caspase-1 from Human Myeloid-Derived Suppressor Cells Can Promote T Cell-Independent Tumor Proliferation.

Science.gov (United States)

Zeng, Qi; Fu, Juan; Korrer, Michael; Gorbounov, Mikhail; Murray, Peter J; Pardoll, Drew; Masica, David L; Kim, Young J

2018-05-01

Immunosuppressive myeloid-derived suppressive cells (MDSCs) are characterized by their phenotypic and functional heterogeneity. To better define their T cell-independent functions within the tumor, sorted monocytic CD14 + CD11b + HLA-DR low/- MDSCs (mMDSC) from squamous cell carcinoma patients showed upregulated caspase-1 activity, which was associated with increased IL1β and IL18 expression. In vitro studies demonstrated that mMDSCs promoted caspase-1-dependent proliferation of multiple squamous carcinoma cell lines in both human and murine systems. In vivo , growth rates of B16, MOC1, and Panc02 were significantly blunted in chimeric mice adoptively transferred with caspase-1 null bone marrow cells under T cell-depleted conditions. Adoptive transfer of wild-type Gr-1 + CD11b + MDSCs from tumor-bearing mice reversed this antitumor response, whereas caspase-1 inhibiting thalidomide-treated MDSCs phenocopied the antitumor response found in caspase-1 null mice. We further hypothesized that MDSC caspase-1 activity could promote tumor-intrinsic MyD88-dependent carcinogenesis. In mice with wild-type caspase-1, MyD88-silenced tumors displayed reduced growth rate, but in chimeric mice with caspase-1 null bone marrow cells, MyD88-silenced tumors did not display differential tumor growth rate. When we queried the TCGA database, we found that caspase-1 expression is correlated with overall survival in squamous cell carcinoma patients. Taken together, our findings demonstrated that caspase-1 in MDSCs is a direct T cell-independent mediator of tumor proliferation. Cancer Immunol Res; 6(5); 566-77. ©2018 AACR . ©2018 American Association for Cancer Research.

Development and validation of a multiplex add-on assay for sepsis biomarkers using xMAP technology

DEFF Research Database (Denmark)

Kofoed, Kristian; Schneider, Uffe Vest; Scheel, Troels

2006-01-01

BACKGROUND: Sepsis is a common and often fatal disease. Because sepsis can be caused by many different organisms, biomarkers that can aid in diagnosing sepsis and monitoring treatment efficacy are highly warranted. New sepsis markers may provide additional information to complement the currently...... triggering receptor expressed on myeloid cells-1 (sTREM-1), and macrophage migration inhibiting factor (MIF) was developed and validated in-house. This 3-plex assay was added to a commercially available interleukin-1beta (IL-1beta), IL-6, IL-8, granulocyte/macrophage colony-stimulating factor, and tumor...

Development and validation of a multiplex add-on assay of biomarkers related to sepsis using xMAP technology

DEFF Research Database (Denmark)

Kofoed, Kristian; Vest Schneider, Uffe; Scheel, Troels

2006-01-01

BACKGROUND: Sepsis is a common and often fatal disease. Because sepsis can be caused by many different organisms, biomarkers that can aid in diagnosing sepsis and monitoring treatment efficacy are highly warranted. New sepsis markers may provide additional information to complement the currently...... triggering receptor expressed on myeloid cells-1 (sTREM-1), and macrophage migration inhibiting factor (MIF) was developed and validated in-house. This 3-plex assay was added to a commercially available interleukin-1beta (IL-1beta), IL-6, IL-8, granulocyte/macrophage colony-stimulating factor, and tumor...

Resistance of human and mouse myeloid leukemia cells to UV radiation

International Nuclear Information System (INIS)

Poljak-Blazi, M.; Osmak, M.; Hadzija, M.

1989-01-01

Sensitivity of mouse bone marrow and myeloid leukemia cells and sensitivity of human myeloid leukemia cells to UV light was tested. Criteria were the in vivo colony-forming ability of UV exposed cells and the inhibition of DNA synthesis during post-irradiation incubation for 24 h in vitro. Mouse bone marrow cells irradiated with a small dose of UV light (5 J/m 2 ) and injected into x-irradiated animals did not form hemopoietic colonies on recipient's spleens, and recipients died. However, mouse leukemia cells, after irradiation with higher doses of UV light, retained the ability to form colonies on the spleens, and all recipient mice died with typical symptoms of leukemia. In vitro, mouse bone marrow cells exhibited high sensitivity to UV light compared to mouse myeloid leukemia cells. Human leukemia cells were also resistant to UV light, but more sensitive than mouse leukemia cells. (author)

Modeling of C/EBPalpha mutant acute myeloid leukemia reveals a common expression signature of committed myeloid leukemia-initiating cells

DEFF Research Database (Denmark)

Kirstetter, Peggy; Schuster, Mikkel B; Bereshchenko, Oksana

2008-01-01

Mutations in the CEBPA gene are present in 7%-10% of human patients with acute myeloid leukemia (AML). However, no genetic models exist that demonstrate their etiological relevance. To mimic the most common mutations affecting CEBPA-that is, those leading to loss of the 42 kDa C/EBPalpha isoform (p...... penetrance. p42-deficient leukemia could be transferred by a Mac1+c-Kit+ population that gave rise only to myeloid cells in recipient mice. Expression profiling of this population against normal Mac1+c-Kit+ progenitors revealed a signature shared with MLL-AF9-transformed AML.......42) while retaining the 30kDa isoform (p30)-we modified the mouse Cebpa locus to express only p30. p30 supported the formation of granulocyte-macrophage progenitors. However, p42 was required for control of myeloid progenitor proliferation, and p42-deficient mice developed AML with complete...

Dual effect of LPS on murine myeloid leukemia cells: Pro-proliferation and anti-proliferation

International Nuclear Information System (INIS)

Yu, Lingling; Zhao, Yingmin; Gu, Xin; Wang, Jijun; Pang, Lei; Zhang, Yanqing; Li, Yaoyao; Jia, Xiaoqin; Wang, Xin; Gu, Jian; Yu, Duonan

2016-01-01

Modification of the bone marrow microenvironment is considered as a promising strategy to control leukemic cell proliferation, diseases progression and relapse after treatment. However, due to the diversity and complexity of the cellular and molecular compartments in the leukemic microenvironment, it is extremely difficult to dissect the role of each individual molecule or cell type in vivo. Here we established an in vitro system to dissect the role of lipopolysaccharide (LPS), stromal cells and endothelial cells in the growth of mouse myeloid tumor cells and B-lymphoma cells. We found that either LPS or bone marrow stromal cells as a feeder layer in culture is required for the proliferation of myeloid tumor cells. Surprisingly, the growth of myeloid leukemic cells on stromal cells is strongly inhibited when coupled with LPS in culture. This opposing effect of LPS, a complete switch from pro-proliferation to antitumor growth is due, at least in part, to the rapidly increased production of interleukin 12, Fas ligand and tissue inhibitor of metalloproteinases-2 from stromal cells stimulated by LPS. These results demonstrate that LPS can either facilitate or attenuate tumor cell proliferation, thus changing the disease course of myeloid leukemias through its direct effect or modulation of the tumor microenvironment. - Highlights: • LPS alone in culture is required for the proliferation of murine myeloid tumor cells. • Bone marrow stromal cells as a feeder layer is also required for the proliferation of myeloid tumor cells. • However, the growth of myeloid tumor cells is inhibited when LPS and stromal cells are both available in culture. • Thus LPS can either facilitate or attenuate tumor growth through its direct effect or modulation of tumor microenvironment.

Dual effect of LPS on murine myeloid leukemia cells: Pro-proliferation and anti-proliferation

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Yu, Lingling [Department of Pediatrics, Jingjiang People' s Hospital, Yangzhou University, Jingjiang 214500 (China); Noncoding RNA Center, Yangzhou University, Yangzhou 225001 (China); Zhao, Yingmin [Department of Pediatrics, Jingjiang People' s Hospital, Yangzhou University, Jingjiang 214500 (China); Gu, Xin; Wang, Jijun; Pang, Lei; Zhang, Yanqing; Li, Yaoyao; Jia, Xiaoqin; Wang, Xin [Noncoding RNA Center, Yangzhou University, Yangzhou 225001 (China); Gu, Jian [Department of Hematology, Yangzhou University School of Clinical Medicine, Yangzhou 225001 (China); Yu, Duonan, E-mail: duonan@yahoo.com [Department of Pediatrics, Jingjiang People' s Hospital, Yangzhou University, Jingjiang 214500 (China); Noncoding RNA Center, Yangzhou University, Yangzhou 225001 (China); Jiangsu Key Laboratory of Integrated Traditional Chinese and Western Medicine for Prevention and Treatment of Senile Disease, Yangzhou 225001 (China); Institute of Comparative Medicine, Yangzhou University, Yangzhou 225001 (China); Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Disease and Zoonosis, Yangzhou 225001 (China)

2016-06-10

Modification of the bone marrow microenvironment is considered as a promising strategy to control leukemic cell proliferation, diseases progression and relapse after treatment. However, due to the diversity and complexity of the cellular and molecular compartments in the leukemic microenvironment, it is extremely difficult to dissect the role of each individual molecule or cell type in vivo. Here we established an in vitro system to dissect the role of lipopolysaccharide (LPS), stromal cells and endothelial cells in the growth of mouse myeloid tumor cells and B-lymphoma cells. We found that either LPS or bone marrow stromal cells as a feeder layer in culture is required for the proliferation of myeloid tumor cells. Surprisingly, the growth of myeloid leukemic cells on stromal cells is strongly inhibited when coupled with LPS in culture. This opposing effect of LPS, a complete switch from pro-proliferation to antitumor growth is due, at least in part, to the rapidly increased production of interleukin 12, Fas ligand and tissue inhibitor of metalloproteinases-2 from stromal cells stimulated by LPS. These results demonstrate that LPS can either facilitate or attenuate tumor cell proliferation, thus changing the disease course of myeloid leukemias through its direct effect or modulation of the tumor microenvironment. - Highlights: • LPS alone in culture is required for the proliferation of murine myeloid tumor cells. • Bone marrow stromal cells as a feeder layer is also required for the proliferation of myeloid tumor cells. • However, the growth of myeloid tumor cells is inhibited when LPS and stromal cells are both available in culture. • Thus LPS can either facilitate or attenuate tumor growth through its direct effect or modulation of tumor microenvironment.

Checkpoints to the Brain: Directing Myeloid Cell Migration to the Central Nervous System

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Meredith Harrison-Brown

2016-12-01

Full Text Available Myeloid cells are a unique subset of leukocytes with a diverse array of functions within the central nervous system during health and disease. Advances in understanding of the unique properties of these cells have inspired interest in their use as delivery vehicles for therapeutic genes, proteins, and drugs, or as “assistants” in the clean-up of aggregated proteins and other molecules when existing drainage systems are no longer adequate. The trafficking of myeloid cells from the periphery to the central nervous system is subject to complex cellular and molecular controls with several ‘checkpoints’ from the blood to their destination in the brain parenchyma. As important components of the neurovascular unit, the functional state changes associated with lineage heterogeneity of myeloid cells are increasingly recognized as important for disease progression. In this review, we discuss some of the cellular elements associated with formation and function of the neurovascular unit, and present an update on the impact of myeloid cells on central nervous system (CNS diseases in the laboratory and the clinic. We then discuss emerging strategies for harnessing the potential of site-directed myeloid cell homing to the CNS, and identify promising avenues for future research, with particular emphasis on the importance of untangling the functional heterogeneity within existing myeloid subsets.

Myeloid cells expressing VEGF and arginase-1 following uptake of damaged retinal pigment epithelium suggests potential mechanism that drives the onset of choroidal angiogenesis in mice.

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Jian Liu

Full Text Available Whilst data recognise both myeloid cell accumulation during choroidal neovascularisation (CNV as well as complement activation, none of the data has presented a clear explanation for the angiogenic drive that promotes pathological angiogenesis. One possibility that is a pre-eminent drive is a specific and early conditioning and activation of the myeloid cell infiltrate. Using a laser-induced CNV murine model, we have identified that disruption of retinal pigment epithelium (RPE and Bruch's membrane resulted in an early recruitment of macrophages derived from monocytes and microglia, prior to angiogenesis and contemporaneous with lesional complement activation. Early recruited CD11b(+ cells expressed a definitive gene signature of selective inflammatory mediators particularly a pronounced Arg-1 expression. Accumulating macrophages from retina and peripheral blood were activated at the site of injury, displaying enhanced VEGF expression, and notably prior to exaggerated VEGF expression from RPE, or earliest stages of angiogenesis. All of these initial events, including distinct VEGF (+ Arg-1(+ myeloid cells, subsided when CNV was established and at the time RPE-VEGF expression was maximal. Depletion of inflammatory CCR2-positive monocytes confirmed origin of infiltrating monocyte Arg-1 expression, as following depletion Arg-1 signal was lost and CNV suppressed. Furthermore, our in vitro data supported a myeloid cell uptake of damaged RPE or its derivatives as a mechanism generating VEGF (+ Arg-1(+ phenotype in vivo. Our results reveal a potential early driver initiating angiogenesis via myeloid-derived VEGF drive following uptake of damaged RPE and deliver an explanation of why CNV develops during any of the stages of macular degeneration and can be explored further for therapeutic gain.

Soluble membrane receptors, interleukin 6, procalcitonin and C reactive protein as prognostic markers in patients with severe sepsis and septic shock.

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Juan-Jesús Ríos-Toro

Full Text Available The objective of this study was to explore the diagnostic and prognostic value of soluble triggering receptor expressed on myeloid cell 1 (sTREM-1, soluble cluster of differentiation 14 (sCD14, soluble cluster of differentiation 163 (sCD163, interleukin-6 (IL-6, procalcitonin (PCT, and C-reactive protein (CRP serum levels for patients with severe sepsis and septic shock in an intensive care unit (ICU.Fifty patients admitted at the ICU with the diagnosis of severe sepsis or septic shock were studied. SOFA and APACHE II scores as well as serum biomarkers were measured at days 0, 2 and 5. The influence of these variables on 28-day mortality was analyzed. Twenty healthy individuals served as controls.Baseline serum concentrations of sTREM-1, sCD163, IL-6 and PCT correlated with SOFA score. Only sTREM-1 levels correlated with APACHE II score. The 28-day mortality rate for all patients was 42%. The absence of risk factors for infection, presence of septic shock, baseline values of sCD14 and decrease of PCT and IL-6 from baseline to day 5 were variables associated to mortality in the univariate analysis. The unique independent factor associated to mortality in the multivariate analysis was a decrease of PCT higher than 50% from days 0 to 5.Serum levels of sTREM-1 are correlated with the severity of sepsis. A 50% decrease of PCT was the unique variable associated with survival in the multivariate analysis.

SAMHD1 restricts HIV-1 replication and regulates interferon production in mouse myeloid cells.

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Ruonan Zhang

Full Text Available SAMHD1 restricts the replication of HIV-1 and other retroviruses in human myeloid and resting CD4(+ T cells and that is counteracted in SIV and HIV-2 by the Vpx accessory protein. The protein is a phosphohydrolase that lowers the concentration of deoxynucleoside triphosphates (dNTP, blocking reverse transcription of the viral RNA genome. Polymorphisms in the gene encoding SAMHD1 are associated with Aicardi-Goutières Syndrome, a neurological disorder characterized by increased type-I interferon production. SAMHD1 is conserved in mammals but its role in restricting virus replication and controlling interferon production in non-primate species is not well understood. We show that SAMHD1 is catalytically active and expressed at high levels in mouse spleen, lymph nodes, thymus and lung. siRNA knock-down of SAMHD1 in bone marrow-derived macrophages increased their susceptibility to HIV-1 infection. shRNA knock-down of SAMHD1 in the murine monocytic cell-line RAW264.7 increased its susceptibility to HIV-1 and murine leukemia virus and increased the levels of the dNTP pool. In addition, SAMHD1 knock-down in RAW264.7 cells induced the production of type-I interferon and several interferon-stimulated genes, modeling the situation in Aicardi-Goutières Syndrome. Our findings suggest that the role of SAMHD1 in restricting viruses is conserved in the mouse. The RAW264.7 cell-line serves as a useful tool to study the antiviral and innate immune response functions of SAMHD1.

Radotinib Induces Apoptosis of CD11b+ Cells Differentiated from Acute Myeloid Leukemia Cells.

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Sook-Kyoung Heo

Full Text Available Radotinib, developed as a BCR/ABL tyrosine kinase inhibitor (TKI, is approved for the second-line treatment of chronic myeloid leukemia (CML in South Korea. However, therapeutic effects of radotinib in acute myeloid leukemia (AML are unknown. In the present study, we demonstrate that radotinib significantly decreases the viability of AML cells in a dose-dependent manner. Kasumi-1 cells were more sensitive to radotinib than NB4, HL60, or THP-1 cell lines. Furthermore, radotinib induced CD11b expression in NB4, THP-1, and Kasumi-1 cells either in presence or absence of all trans-retinoic acid (ATRA. We found that radotinib promoted differentiation and induced CD11b expression in AML cells by downregulating LYN. However, CD11b expression induced by ATRA in HL60 cells was decreased by radotinib through upregulation of LYN. Furthermore, radotinib mainly induced apoptosis of CD11b+ cells in the total population of AML cells. Radotinib also increased apoptosis of CD11b+ HL60 cells when they were differentiated by ATRA/dasatinib treatment. We show that radotinib induced apoptosis via caspase-3 activation and the loss of mitochondrial membrane potential (ΔΨm in CD11b+ cells differentiated from AML cells. Our results suggest that radotinib may be used as a candidate drug in AML or a chemosensitizer for treatment of AML by other therapeutics.

Modeling chronic myeloid leukemia in immunodeficient mice reveals expansion of aberrant mast cells and accumulation of pre-B cells

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Askmyr, M; Ågerstam, H; Lilljebjörn, H; Hansen, N; Karlsson, C; Palffy, S von; Landberg, N; Högberg, C; Lassen, C; Rissler, M; Richter, J; Ehinger, M; Järås, M; Fioretos, T

2014-01-01

Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm that, if not treated, will progress into blast crisis (BC) of either myeloid or B lymphoid phenotype. The BCR-ABL1 fusion gene, encoding a constitutively active tyrosine kinase, is thought to be sufficient to cause chronic phase (CP) CML, whereas additional genetic lesions are needed for progression into CML BC. To generate a humanized CML model, we retrovirally expressed BCR-ABL1 in the cord blood CD34 + cells and transplanted these into NOD-SCID (non-obese diabetic/severe-combined immunodeficient) interleukin-2-receptor γ-deficient mice. In primary mice, BCR-ABL1 expression induced an inflammatory-like state in the bone marrow and spleen, and mast cells were the only myeloid lineage specifically expanded by BCR-ABL1. Upon secondary transplantation, the pronounced inflammatory phenotype was lost and mainly human mast cells and macrophages were found in the bone marrow. Moreover, a striking block at the pre-B-cell stage was observed in primary mice, resulting in an accumulation of pre-B cells. A similar block in B-cell differentiation could be confirmed in primary cells from CML patients. Hence, this humanized mouse model of CML reveals previously unexplored features of CP CML and should be useful for further studies to understand the disease pathogenesis of CML

Allogeneic stem cell transplantation in acute myeloid leukemia

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Natasha Ali

2012-11-01

Full Text Available We report a case series of 12 patients with acute myeloid leukemia who underwent allogeneic stem cell transplant with a matched related donor. Male to female ratio was 1:1. The main complication post-transplant was graft-versus-host disease (n=7 patients. Transplant-related mortality involved one patient; cause of death was multi-organ failure. After a median follow up of 36.0±11.3 months, overall survival was 16%.

Monoclonal Antibody Therapy in Treating Patients With Ovarian Epithelial Cancer, Melanoma, Acute Myeloid Leukemia, Myelodysplastic Syndrome, or Non-Small Cell Lung Cancer

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2013-01-09

Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Atypical Chronic Myeloid Leukemia, BCR-ABL1 Negative; Myelodysplastic/Myeloproliferative Neoplasm, Unclassifiable; Previously Treated Myelodysplastic Syndromes; Recurrent Adult Acute Myeloid Leukemia; Recurrent Melanoma; Recurrent Non-small Cell Lung Cancer; Recurrent Ovarian Epithelial Cancer; Stage IV Melanoma; Stage IV Non-small Cell Lung Cancer

Alloreactive natural killer cells for the treatment of acute myeloid leukemia: from stem cell transplantation to adoptive immunotherapy

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Loredana eRuggeri

2015-10-01

Full Text Available Natural killer cells express activating and inhibitory receptors which recognize MHC class I alleles, termed Killer cell Immunoglobulin-like Receptors (KIRs. Preclinical and clinical data from haploidentical T-cell depleted stem cell transplantation have demonstrated that alloreactive KIR-L mismatched natural killer cells play a major role as effectors against acute myeloid leukemia. Outside the transplantation setting, several reports have proven the safety and feasibility of natural killer cell infusion in acute myeloid leukemia patients and, in some cases, provided evidence that transferred NK cells are functionally alloreactive and may have a role in disease control. Aim of the present work is to briefly summarize the most recent advances in the field by moving from the first preclinical and clinical demonstration of donor NK alloreactivity in the transplantation setting to the most recent attempts of exploiting the use of alloreactive NK cell infusion as a means of adoptive immunotherapy against acute myeloid leukemia. Altogether, these data highlight the pivotal role of NK cells for the development of novel immunological approaches in the clinical management of acute myeloid leukemia.

Isolation and killing of candidate chronic myeloid leukemia stem cells by antibody targeting of IL-1 receptor accessory protein

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Järås, Marcus; Johnels, Petra; Hansen, Nils Gunder

2010-01-01

Chronic myeloid leukemia (CML) is genetically characterized by the Philadelphia (Ph) chromosome, formed through a reciprocal translocation between chromosomes 9 and 22 and giving rise to the constitutively active tyrosine kinase P210 BCR/ABL1. Therapeutic strategies aiming for a cure of CML...... will require full eradication of Ph chromosome-positive (Ph(+)) CML stem cells. Here we used gene-expression profiling to identify IL-1 receptor accessory protein (IL1RAP) as up-regulated in CML CD34(+) cells and also in cord blood CD34(+) cells as a consequence of retroviral BCR/ABL1 expression. To test...

Cyclophosphamide-induced myeloid-derived suppressor cell population is immunosuppressive but not identical to myeloid-derived suppressor cells induced by growing TC-1 tumors

Czech Academy of Sciences Publication Activity Database

Mikyšková, Romana; Indrová, Marie; Polláková, Veronika; Bieblová, Jana; Šímová, Jana; Reiniš, Milan

2012-01-01

Roč. 35, č. 5 (2012), s. 374-384 ISSN 1524-9557 R&D Projects: GA ČR(CZ) GPP301/11/P220; GA ČR GA301/09/1024; GA ČR GA301/07/1410 EU Projects: European Commission(XE) 18933 - CLINIGENE Institutional research plan: CEZ:AV0Z50520514 Institutional support: RVO:68378050 Keywords : myeloid-derived suppressor cells * cyclophosphamide * all-trans-retinoic acid * IL-12 * HPV16 Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.463, year: 2012

Targeting myeloid cells to the brain using non-myeloablative conditioning.

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Chotima Böttcher

Full Text Available Bone marrow-derived cells (BMDCs are able to colonize the central nervous system (CNS at sites of damage. This ability makes BMDCs an ideal cellular vehicle for transferring therapeutic genes/molecules to the CNS. However, conditioning is required for bone marrow-derived myeloid cells to engraft in the brain, which so far has been achieved by total body irradiation (TBI and by chemotherapy (e.g. busulfan treatment. Unfortunately, both regimens massively disturb the host's hematopoietic compartment. Here, we established a conditioning protocol to target myeloid cells to sites of brain damage in mice using non-myeloablative focal head irradiation (HI. This treatment was associated with comparatively low inflammatory responses in the CNS despite cranial radiation doses which are identical to TBI, as revealed by gene expression analysis of cytokines/chemokines such as CCL2, CXCL10, TNF-α and CCL5. HI prior to bone marrow transplantation resulted in much lower levels of blood chimerism defined as the percentage of donor-derived cells in peripheral blood ( 95% or busulfan treatment (> 50%. Nevertheless, HI effectively recruited myeloid cells to the area of motoneuron degeneration in the brainstem within 7 days after facial nerve axotomy. In contrast, no donor-derived cells were detected in the lesioned facial nucleus of busulfan-treated animals up to 2 weeks after transplantation. Our findings suggest that myeloid cells can be targeted to sites of brain damage even in the presence of very low levels of peripheral blood chimerism. We established a novel non-myeloablative conditioning protocol with minimal disturbance of the host's hematopoietic system for targeting BMDCs specifically to areas of pathology in the brain.

Myeloid derived suppressor cells as therapeutic target in hematological malignancies

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Kim eDe Veirman

2014-12-01

Full Text Available Myeloid derived suppressor cells (MDSC are a heterogeneous population of immature myeloid cells that accumulate during pathological conditions such as cancer and are associated with a poor clinical outcome. MDSC expansion hampers the host anti-tumor immune response by inhibition of T cell proliferation, cytokine secretion and recruitment of regulatory T cells. In addition, MDSC exert non-immunological functions including the promotion of angiogenesis, tumor invasion and metastasis. Recent years, MDSC are considered as a potential target in solid tumors and hematological malignancies to enhance the effects of currently used immune modulating agents. This review focuses on the characteristics, distribution, functions, cell-cell interactions and targeting of MDSC in hematological malignancies including multiple myeloma, lymphoma and leukemia.

G-CSF/anti-G-CSF antibody complexes drive the potent recovery and expansion of CD11b+Gr-1+ myeloid cells without compromising CD8+ T cell immune responses

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2013-01-01

Background Administration of recombinant G-CSF following cytoreductive therapy enhances the recovery of myeloid cells, minimizing the risk of opportunistic infection. Free G-CSF, however, is expensive, exhibits a short half-life, and has poor biological activity in vivo. Methods We evaluated whether the biological activity of G-CSF could be improved by pre-association with anti-G-CSF mAb prior to injection into mice. Results We find that the efficacy of G-CSF therapy can be enhanced more than 100-fold by pre-association of G-CSF with an anti-G-CSF monoclonal antibody (mAb). Compared with G-CSF alone, administration of G-CSF/anti-G-CSF mAb complexes induced the potent expansion of CD11b+Gr-1+ myeloid cells in mice with or without concomitant cytoreductive treatment including radiation or chemotherapy. Despite driving the dramatic expansion of myeloid cells, in vivo antigen-specific CD8+ T cell immune responses were not compromised. Furthermore, injection of G-CSF/anti-G-CSF mAb complexes heightened protective immunity to bacterial infection. As a measure of clinical value, we also found that antibody complexes improved G-CSF biological activity much more significantly than pegylation. Conclusions Our findings provide the first evidence that antibody cytokine complexes can effectively expand myeloid cells, and furthermore, that G-CSF/anti-G-CSF mAb complexes may provide an improved method for the administration of recombinant G-CSF. PMID:24279871

β-Catenin–regulated myeloid cell adhesion and migration determine wound healing

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Amini-Nik, Saeid; Cambridge, Elizabeth; Yu, Winston; Guo, Anne; Whetstone, Heather; Nadesan, Puviindran; Poon, Raymond; Hinz, Boris; Alman, Benjamin A.

2014-01-01

A β-catenin/T cell factor–dependent transcriptional program is critical during cutaneous wound repair for the regulation of scar size; however, the relative contribution of β-catenin activity and function in specific cell types in the granulation tissue during the healing process is unknown. Here, cell lineage tracing revealed that cells in which β-catenin is transcriptionally active express a gene profile that is characteristic of the myeloid lineage. Mice harboring a macrophage-specific deletion of the gene encoding β-catenin exhibited insufficient skin wound healing due to macrophage-specific defects in migration, adhesion to fibroblasts, and ability to produce TGF-β1. In irradiated mice, only macrophages expressing β-catenin were able to rescue wound-healing deficiency. Evaluation of scar tissue collected from patients with hypertrophic and normal scars revealed a correlation between the number of macrophages within the wound, β-catenin levels, and cellularity. Our data indicate that β-catenin regulates myeloid cell motility and adhesion and that β-catenin–mediated macrophage motility contributes to the number of mesenchymal cells and ultimate scar size following cutaneous injury. PMID:24837430

Expression profile of CREB knockdown in myeloid leukemia cells

International Nuclear Information System (INIS)

Pellegrini, Matteo; Cheng, Jerry C; Voutila, Jon; Judelson, Dejah; Taylor, Julie; Nelson, Stanley F; Sakamoto, Kathleen M

2008-01-01

The cAMP Response Element Binding Protein, CREB, is a transcription factor that regulates cell proliferation, differentiation, and survival in several model systems, including neuronal and hematopoietic cells. We demonstrated that CREB is overexpressed in acute myeloid and leukemia cells compared to normal hematopoietic stem cells. CREB knockdown inhibits leukemic cell proliferation in vitro and in vivo, but does not affect long-term hematopoietic reconstitution. To understand downstream pathways regulating CREB, we performed expression profiling with RNA from the K562 myeloid leukemia cell line transduced with CREB shRNA. By combining our expression data from CREB knockdown cells with prior ChIP data on CREB binding we were able to identify a list of putative CREB regulated genes. We performed extensive analyses on the top genes in this list as high confidence CREB targets. We found that this list is enriched for genes involved in cancer, and unexpectedly, highly enriched for histone genes. Furthermore, histone genes regulated by CREB were more likely to be specifically expressed in hematopoietic lineages. Decreased expression of specific histone genes was validated in K562, TF-1, and primary AML cells transduced with CREB shRNA. We have identified a high confidence list of CREB targets in K562 cells. These genes allow us to begin to understand the mechanisms by which CREB contributes to acute leukemia. We speculate that regulation of histone genes may play an important role by possibly altering the regulation of DNA replication during the cell cycle

Omega 3 fatty acids reduce myeloid progenitor cell frequency in the bone marrow of mice and promote progenitor cell differentiation

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Sollars Vincent E

2009-03-01

Full Text Available Abstract Background Omega 3 fatty acids have been found to inhibit proliferation, induce apoptosis, and promote differentiation in various cell types. The processes of cell survival, expansion, and differentiation are of key importance in the regulation of hematopoiesis. We investigated the role of omega 3 fatty acids in controlling the frequency of various myeloid progenitor cells in the bone marrow of mice. Increased progenitor cell frequency and blocked differentiation are characteristics of hematopoietic disorders of the myeloid lineage, such as myeloproliferative diseases and myeloid leukemias. Results We found that increasing the proportion of omega 3 fatty acids relative to the proportion of omega 6 fatty acids in the diet caused increased differentiation and reduced the frequency of myeloid progenitor cells in the bone marrow of mice. Furthermore, this had no adverse effect on peripheral white blood cell counts. Conclusion Our results indicate that omega 3 fatty acids impact hematopoietic differentiation by reducing myeloid progenitor cell frequency in the bone marrow and promoting progenitor cell differentiation. Further exploration of this discovery could lead to the use of omega 3 fatty acids as a therapeutic option for patients that have various disorders of hematopoiesis.

Autonomous feedback loop of RUNX1-p53-CBFB in acute myeloid leukemia cells.

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Morita, Ken; Noura, Mina; Tokushige, Chieko; Maeda, Shintaro; Kiyose, Hiroki; Kashiwazaki, Gengo; Taniguchi, Junichi; Bando, Toshikazu; Yoshida, Kenichi; Ozaki, Toshifumi; Matsuo, Hidemasa; Ogawa, Seishi; Liu, Pu Paul; Nakahata, Tatsutoshi; Sugiyama, Hiroshi; Adachi, Souichi; Kamikubo, Yasuhiko

2017-11-30

Although runt-related transcription factor 1 (RUNX1) and its associating core binding factor-β (CBFB) play pivotal roles in leukemogenesis, and inhibition of RUNX1 has now been widely recognized as a novel strategy for anti-leukemic therapies, it has been elusive how leukemic cells could acquire the serious resistance against RUNX1-inhibition therapies and also whether CBFB could participate in this process. Here, we show evidence that p53 (TP53) and CBFB are sequentially up-regulated in response to RUNX1 depletion, and their mutual interaction causes the physiological resistance against chemotherapy for acute myeloid leukemia (AML) cells. Mechanistically, p53 induced by RUNX1 gene silencing directly binds to CBFB promoter and stimulates its transcription as well as its translation, which in turn acts as a platform for the stabilization of RUNX1, thereby creating a compensative RUNX1-p53-CBFB feedback loop. Indeed, AML cells derived from relapsed cases exhibited higher CBFB expression levels compared to those from primary AML cells at diagnosis, and these CBFB expressions were positively correlated to those of p53. Our present results underscore the importance of RUNX1-p53-CBFB regulatory loop in the development and/or maintenance of AML cells, which could be targeted at any sides of this triangle in strategizing anti-leukemia therapies.

Systemic RNAi-mediated Gene Silencing in Nonhuman Primate and Rodent Myeloid Cells

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Tatiana I Novobrantseva

2012-01-01

Full Text Available Leukocytes are central regulators of inflammation and the target cells of therapies for key diseases, including autoimmune, cardiovascular, and malignant disorders. Efficient in vivo delivery of small interfering RNA (siRNA to immune cells could thus enable novel treatment strategies with broad applicability. In this report, we develop systemic delivery methods of siRNA encapsulated in lipid nanoparticles (LNP for durable and potent in vivo RNA interference (RNAi-mediated silencing in myeloid cells. This work provides the first demonstration of siRNA-mediated silencing in myeloid cell types of nonhuman primates (NHPs and establishes the feasibility of targeting multiple gene targets in rodent myeloid cells. The therapeutic potential of these formulations was demonstrated using siRNA targeting tumor necrosis factor-α (TNFα which induced substantial attenuation of disease progression comparable to a potent antibody treatment in a mouse model of rheumatoid arthritis (RA. In summary, we demonstrate a broadly applicable and therapeutically relevant platform for silencing disease genes in immune cells.

Radiation responses of hematopoietic-cells and inducing acute myeloid leukemia

International Nuclear Information System (INIS)

Ojima, Mitsuaki; Hirouchi, Tokuhisa

2016-01-01

Leukemia has consistently held the interest of researchers from the beginning of radiation carcinogenesis. One of the major reasons for this interest is the availability of several strains of mice that develop leukemia following radiation exposure after a short latency period that resemble those found in A-Bomb survivors. Previous studies have shown that rAML (Radiation-induced Acute Myeloid Leukemia) in mice show inactivation of Sfpi1 gene and a hemizygous deletion in chromosome 2. Leukemic stem cells in murine rAML have been reported to share some characteristics with common myeloid progenitor cells. In this review, we will discuss the possible mechanisms in the development of rAML stem cells, focusing on the alterations found in the leukemic stem cells and as well as the environment in which these leukemic stem cells are developed, such cytokine expression, as Well as alterations that may be found in other cells residing in the bone marrow. Hematopoietic stem cells respond to radiation exposure both as a single cell and as a part of the differentiating hematopoietic tissue for several months prior to its transformation to a rAML stem cell. It is however unclear how these 2 responses contribute to the development of the rAML stem cell. This review covers previous reports and examines the development of the rAML stem cell in detail. (author)

Residency and Activation of Myeloid Cells During Remodeling of the Prepartum Murine Cervix1

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Payne, Kimberly J.; Clyde, Lindsey A.; Weldon, Abby J.; Milford, Terry-Ann; Yellon, Steven M.

2012-01-01

ABSTRACT Remodeling of the cervix is a critical early component of parturition and resembles an inflammatory process. Infiltration and activation of myeloid immune cells along with production of proinflammatory mediators and proteolytic enzymes are hypothesized to regulate cervical remodeling as pregnancy nears term. The present study standardized an approach to assess resident populations of immune cells and phenotypic markers of functional activities related to the mechanism of extracellular matrix degradation in the cervix in preparation for birth. Analysis of cells from the dispersed cervix of mice that were nonpregnant or pregnant (Days 15 and 18 postbreeding) by multicolor flow cytometry indicated increased total cell numbers with pregnancy as well as increased numbers of macrophages, the predominant myeloid cell, by Day 18, the day before birth. The number of activated macrophages involved in matrix metalloproteinase induction (CD147) and signaling for matrix adhesion (CD169) significantly increased by the day before birth. Expression of the adhesion markers CD54 and CD11b by macrophages decreased in the cervix by Day 18 versus that on Day 15 or in nonpregnant mice. The census of cells that expressed the migration marker CD62L was unaffected by pregnancy. The data suggest that remodeling of the cervix at term in mice is associated with recruitment and selective activation of macrophages that promote extracellular matrix degradation. Indices of immigration and activities by macrophages may thus serve as markers for local immune cell activity that is critical for ripening of the cervix in the final common mechanism for parturition at term. PMID:22914314

Honey bee venom combined with 1,25-dihydroxyvitamin D3as a highly efficient inducer of differentiation in human acute myeloid leukemia cells.

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Mohseni-Kouchesfahani, Homa; Nabioni, Mohammad; Khosravi, Zahra; Rahimi, Maryam

2017-01-01

Most cancer cells exhibit a defect in their capacity to mature into nonreplicating adult cells and existing in a highly proliferating state. Differentiation therapy by agents such as 1,25-dihydroxyvitamin D3(1,25-(OH)2 VD3) represents a useful approach for the treatment of cancer including acute myeloid leukemia. Human myeloid leukemia cell lines are induced to terminal differentiation into monocyte lineage by 1,25-(OH)2 VD3. However, usage of these findings in the clinical trials is limited by calcemic effects of 1,25-(OH)2 VD3. Attempts to overcome this problem have focused on a combination of low concentrations 1,25-(OH)2 VD3 with other compounds to induce differentiation of HL-60 cells. In this study, the effect of honey bee venom (BV) and 1,25-(OH)2 VD3, individually and in combination, on proliferation and differentiation of human myeloid leukemia HL-60 cells were assayed. In this in vitro study, toxic and nontoxic concentrations of BV and 1,25-(OH)2 VD3 were tested using Trypan blue stained cell counting and (3[4, 5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay. In addition, differentiation of cells was assayed using a Wright-Giemsa staining and nitroblue tetrazolium reduction test. Data were analyzed by a one-way analysis of the variance test using SPSS software. Our findings showed that both the BV and 1,25-(OH)2 VD3, in a dose and time-dependent manner, caused cell death at high concentrations and inhibited cell proliferation at lower concentrations. About 5 nM of 1,25-(OH)2 VD3 induced differentiation of HL-60 cells to monocytes after 72 h. 2.5 μg/ml of BV suppressed proliferation of HL-60 cells but had not any effects on their differentiation, whereas in combination with 5 nM of 1,25-(OH)2 VD3, it enhanced antiproliferative and differentiation potency of 1,25-(OH)2 VD3. These results indicate that BV potentiates the 1,25-(OH)2 VD3-induced HL-60 cell differentiation into monocytes.

Intensive chemotherapy for acute myeloid leukemia differentially affects circulating TC1, TH1, TH17 and TREG cells

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Gjertsen Bjørn

2010-07-01

Full Text Available Abstract Background Several observations suggest that immunological events early after chemotherapy, possibly during the period of severe treatment-induced cytopenia, are important for antileukemic immune reactivity in acute myeloid leukemia (AML. We therefore investigated the frequencies of various T cell subsets (TC1, TH1, TH17 and CD25+ FoxP3+ TREG cells in AML patients with untreated disease and following intensive chemotherapy. Results Relative levels of circulating TC1 and TH1 cells were decreased in patients with severe chemotherapy-induced cytopenia, whereas TH17 levels did not differ from healthy controls. Increased levels of regulatory CD25+ FoxP3+ T cells were detected in AML patients with untreated disease, during chemotherapy-induced cytopenia and during regeneration after treatment. TH17 and TH1 levels were significantly higher in healthy males than females, but this gender difference was not detected during chemotherapy-induced cytopenia. Finally, exogenous IL17-A usually had no or only minor effects on proliferation of primary human AML cells. Conclusions We conclude that the effect of intensive AML chemotherapy differ between circulating T cell subsets, relative frequencies of TH17 cells are not affected by chemotherapy and this subset may affect AML cells indirectly through their immunoregulatory effects but probably not through direct effects of IL17-A.

Immunodetection of myeloid and plasmacytoid dendritic cells in mammary carcinomas of female dogs

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Mayara C. Rosolem

2015-11-01

Full Text Available ABSTRACT: Dendritic cells have attracted great interest from researchers as they may be used as targets of tumor immune evasion mechanisms. The main objective of this study was to evaluate the relationship between the dendritic cells (DCs subpopulation in simple type mammary carcinomas in female dogs. Two groups of samples were used: the control group consisted of 18 samples of mammary tissue without changes and the tumor group with 26 simple type mammary carcinomas. In these groups, we evaluated the immunodetection of immature and mature myeloid DCs, plasmacytoid DCs and MHC-II. In mammary tumor, mature myeloid DCs predominated in the peritumoral region, while immature myeloid DCs and plasmacytoid DCs were evident in the intratumoral region. Immunostaining of MHC-II was visualized in mammary acini (control group, in tumor cells and inflammatory infiltration associated with tumors. The comparison between the control and tumor groups showed a statistically significant difference between immature myeloid DCs, mature myeloid DCs and plasmacytoid DCs. The immunodetection of MHC-II was not significant when comparing the groups. The predominance of immature DCs in the tumor group is possibly related to an inefficient immune response, promoting the development and survival of tumor cells. The presence of plasmacytoid DCs in the same group suggests a worse prognosis for female dogs with mammary tumors. Therefore, the ability of differentiation of canine dendritic cells could be influenced by neoplastic cells and by the tumor microenvironment.

Induced pluripotent stem cells-derived myeloid-derived suppressor cells regulate the CD8+ T cell response

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Daniel Joyce

2018-05-01

Full Text Available Myeloid-derived suppressor cells (MDSCs are markedly increased in cancer patients and tumor-bearing mice and promote tumor growth and survival by inhibiting host innate and adaptive immunity. In this study, we generated and characterized MDSCs from murine-induced pluripotent stem cells (iPSCs. The iPSCs were co-cultured with OP9 cells, stimulated with GM-CSF, and became morphologically heterologous under co-culturing with hepatic stellate cells. Allogeneic and OVA-specific antigen stimulation demonstrated that iPS-MDSCs have a T-cell regulatory function. Furthermore, a popliteal lymph node assay and autoimmune hepatitis model showed that iPS-MDSCs also regulate immune responsiveness in vivo and have a therapeutic effect against hepatitis. Taken together, our results demonstrated a method of generating functional MDSCs from iPSCs and highlighted the potential of iPS-MDSCs as a key cell therapy resource for transplantation and autoimmune diseases. Keywords: Myeloid-derived suppressor cells, Induced pluripotent stem cells, T cell response

LMP1-mediated glycolysis induces myeloid-derived suppressor cell expansion in nasopharyngeal carcinoma.

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Ting-Ting Cai

2017-07-01

Full Text Available Myeloid-derived suppressor cells (MDSCs are expanded in tumor microenvironments, including that of Epstein-Barr virus (EBV-associated nasopharyngeal carcinoma (NPC. The link between MDSC expansion and EBV infection in NPC is unclear. Here, we show that EBV latent membrane protein 1 (LMP1 promotes MDSC expansion in the tumor microenvironment by promoting extra-mitochondrial glycolysis in malignant cells, which is a scenario for immune escape initially suggested by the frequent, concomitant detection of abundant LMP1, glucose transporter 1 (GLUT1 and CD33+ MDSCs in tumor sections. The full process has been reconstituted in vitro. LMP1 promotes the expression of multiple glycolytic genes, including GLUT1. This metabolic reprogramming results in increased expression of the Nod-like receptor family protein 3 (NLRP3 inflammasome, COX-2 and P-p65 and, consequently, increased production of IL-1β, IL-6 and GM-CSF. Finally, these changes in the environment of malignant cells result in enhanced NPC-derived MDSC induction. One key step is the physical interaction of LMP1 with GLUT1 to stabilize the GLUT1 protein by blocking its K48-ubiquitination and p62-dependent autolysosomal degradation. This work indicates that LMP1-mediated glycolysis regulates IL-1β, IL-6 and GM-CSF production through the NLRP3 inflammasome, COX-2 and P-p65 signaling pathways to enhance tumor-associated MDSC expansion, which leads to tumor immunosuppression in NPC.

Testicular myeloid sarcoma: case report.

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Zago, Luzia Beatriz Ribeiro; Ladeia, Antônio Alexandre Lisbôa; Etchebehere, Renata Margarida; de Oliveira, Leonardo Rodrigues

2013-01-01

Myeloid sarcomas are extramedullary solid tumors composed of immature granulocytic precursor cells. In association with acute myeloid leukemia and other myeloproliferative disorders, they may arise concurrently with compromised bone marrow related to acute myeloid leukemia, as a relapsed presentation, or occur as the first manifestation. The testicles are considered to be an uncommon site for myeloid sarcomas. No therapeutic strategy has been defined as best but may include chemotherapy, radiotherapy and/or hematopoietic stem cell transplantation. This study reports the evolution of a patient with testicular myeloid sarcoma as the first manifestation of acute myeloid leukemia. The patient initially refused medical treatment and died five months after the clinical condition started.

Activation of liver X receptor decreases atherosclerosis in Ldlr⁻/⁻ mice in the absence of ATP-binding cassette transporters A1 and G1 in myeloid cells

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Kappus, Mojdeh S.; Murphy, Andrew J.; Abramowicz, Sandra; Ntonga, Vusisizwe; Welch, Carrie L.; Tall, Alan R.; Westerterp, Marit

2014-01-01

Liver X receptor (LXR) activators decrease atherosclerosis in mice. LXR activators (1) directly upregulate genes involved in reverse cholesterol transport and (2) exert anti-inflammatory effects mediated by transrepression of nuclear factor-κB target genes. We investigated whether myeloid cell

Distinct regulation of c-myb gene expression by HoxA9, Meis1 and Pbx proteins in normal hematopoietic progenitors and transformed myeloid cells

International Nuclear Information System (INIS)

Dassé, E; Volpe, G; Walton, D S; Wilson, N; Del Pozzo, W; O'Neill, L P; Slany, R K; Frampton, J; Dumon, S

2012-01-01

The proto-oncogenic protein c-Myb is an essential regulator of hematopoiesis and is frequently deregulated in hematological diseases such as lymphoma and leukemia. To gain insight into the mechanisms underlying the aberrant expression of c-Myb in myeloid leukemia, we analyzed and compared c-myb gene transcriptional regulation using two cell lines modeling normal hematopoietic progenitor cells (HPCs) and transformed myelomonocytic blasts. We report that the transcription factors HoxA9, Meis1, Pbx1 and Pbx2 bind in vivo to the c-myb locus and maintain its expression through different mechanisms in HPCs and leukemic cells. Our analysis also points to a critical role for Pbx2 in deregulating c-myb expression in murine myeloid cells cotransformed by the cooperative activity of HoxA9 and Meis1. This effect is associated with an intronic positioning of epigenetic marks and RNA polymerase II binding in the orthologous region of a previously described alternative promoter for c-myb. Taken together, our results could provide a first hint to explain the abnormal expression of c-myb in leukemic cells

GSK-3 Inhibition Sensitizes Acute Myeloid Leukemia Cells to 1,25D-Mediated Differentiation

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Gupta, Kalpana; Stefan, Tammy; Ignatz-Hoover, James; Moreton, Stephen; Parizher, Gary; Saunthararajah, Yogen; Wald, David N.

2017-01-01

1,25-dihydroxyvitamin D3 (1,25D), the biologically active form of vitamin D, is widely considered a promising therapy for acute myeloid leukemia (AML) based on its ability to drive differentiation of leukemic cells. However, clinical trials have been disappointing in part to dose-limiting hypercalcemia. Here we show how inhibiting glycogen synthase kinase 3 (GSK3) can improve the differentiation response of AML cells to 1,25D-mediated differentiation. GSK3 inhibition in AML cells enhanced the differentiating effects of low concentrations of 1,25D. In addition, GSK3 inhibition augmented the ability of 1,25D to induce irreversible growth inhibition and slow the progression of AML in mouse models. Mechanistic studies revealed that GSK3 inhibition led to the hyperphosphorylation of the vitamin D receptor (VDR), enabling an interaction between VDR and the coactivator, SRC-3 (NCOA3), thereby increasing transcriptional activity. We also found that activation of JNK-mediated pathways in response to GSK3 inhibition contributed to the potentiation of 1,25D-induced differentiation. Taken together, our findings offer a preclinical rationale to explore the repositioning of GSK3 inhibitors to enhance differentiation-based therapy for AML treatment. PMID:26964622

Differentiation Therapy of Acute Myeloid Leukemia

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Gocek, Elzbieta; Marcinkowska, Ewa

2011-01-01

Acute Myeloid Leukemia (AML) is a predominant acute leukemia among adults, characterized by accumulation of malignantly transformed immature myeloid precursors. A very attractive way to treat myeloid leukemia, which is now called ‘differentiation therapy’, was proposed as in vitro studies have shown that a variety of agents stimulate differentiation of the cell lines isolated from leukemic patients. One of the differentiation-inducing agents, all-trans retinoic acid (ATRA), which can induce granulocytic differentiation in myeloid leukemic cell lines, has been introduced into clinics to treat patients with acute promyelocytic leukemia (APL) in which a PML-RARA fusion protein is generated by a t(15;17)(q22;q12) chromosomal translocation. Because differentiation therapy using ATRA has significantly improved prognosis for patients with APL, many efforts have been made to find alternative differentiating agents. Since 1,25-dihydroxyvitamin D 3 (1,25D) is capable of inducing in vitro monocyte/macrophage differentiation of myeloid leukemic cells, clinical trials have been performed to estimate its potential to treat patients with AML or myelodysplastic syndrome (MDS). Unfortunately therapeutic concentrations of 1,25D can induce potentially fatal systemic hypercalcemia, thus limiting clinical utility of that compound. Attempts to overcome this problem have focused on the synthesis of 1,25D analogs (VDAs) which retain differentiation inducing potential, but lack its hypercalcemic effects. This review aims to discuss current problems and potential solutions in differentiation therapy of AML

Differentiation Therapy of Acute Myeloid Leukemia

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Gocek, Elzbieta; Marcinkowska, Ewa, E-mail: ema@cs.uni.wroc.pl [Department of Biotechnology, University of Wroclaw, ul Tamka 2, Wroclaw 50-137 (Poland)

2011-05-16

Acute Myeloid Leukemia (AML) is a predominant acute leukemia among adults, characterized by accumulation of malignantly transformed immature myeloid precursors. A very attractive way to treat myeloid leukemia, which is now called ‘differentiation therapy’, was proposed as in vitro studies have shown that a variety of agents stimulate differentiation of the cell lines isolated from leukemic patients. One of the differentiation-inducing agents, all-trans retinoic acid (ATRA), which can induce granulocytic differentiation in myeloid leukemic cell lines, has been introduced into clinics to treat patients with acute promyelocytic leukemia (APL) in which a PML-RARA fusion protein is generated by a t(15;17)(q22;q12) chromosomal translocation. Because differentiation therapy using ATRA has significantly improved prognosis for patients with APL, many efforts have been made to find alternative differentiating agents. Since 1,25-dihydroxyvitamin D{sub 3} (1,25D) is capable of inducing in vitro monocyte/macrophage differentiation of myeloid leukemic cells, clinical trials have been performed to estimate its potential to treat patients with AML or myelodysplastic syndrome (MDS). Unfortunately therapeutic concentrations of 1,25D can induce potentially fatal systemic hypercalcemia, thus limiting clinical utility of that compound. Attempts to overcome this problem have focused on the synthesis of 1,25D analogs (VDAs) which retain differentiation inducing potential, but lack its hypercalcemic effects. This review aims to discuss current problems and potential solutions in differentiation therapy of AML.

Mast cell-deficient Kit(W-sh) "Sash" mutant mice display aberrant myelopoiesis leading to the accumulation of splenocytes that act as myeloid-derived suppressor cells.

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Michel, Anastasija; Schüler, Andrea; Friedrich, Pamela; Döner, Fatma; Bopp, Tobias; Radsak, Markus; Hoffmann, Markus; Relle, Manfred; Distler, Ute; Kuharev, Jörg; Tenzer, Stefan; Feyerabend, Thorsten B; Rodewald, Hans-Reimer; Schild, Hansjörg; Schmitt, Edgar; Becker, Marc; Stassen, Michael

2013-06-01

Mast cell-deficient Kit(W-sh) "sash" mice are widely used to investigate mast cell functions. However, mutations of c-Kit also affect additional cells of hematopoietic and nonimmune origin. In this study, we demonstrate that Kit(W-sh) causes aberrant extramedullary myelopoiesis characterized by the expansion of immature lineage-negative cells, common myeloid progenitors, and granulocyte/macrophage progenitors in the spleen. A consistent feature shared by these cell types is the reduced expression of c-Kit. Populations expressing intermediate and high levels of Ly6G, a component of the myeloid differentiation Ag Gr-1, are also highly expanded in the spleen of sash mice. These cells are able to suppress T cell responses in vitro and phenotypically and functionally resemble myeloid-derived suppressor cells (MDSC). MDSC typically accumulate in tumor-bearing hosts and are able to dampen immune responses. Consequently, transfer of MDSC from naive sash mice into line 1 alveolar cell carcinoma tumor-bearing wild-type littermates leads to enhanced tumor progression. However, although it can also be observed in sash mice, accelerated growth of transplanted line 1 alveolar cell carcinoma tumors is a mast cell-independent phenomenon. Thus, the Kit(W-sh) mutation broadly affects key steps in myelopoiesis that may have an impact on mast cell research.

Characterization of miRNomes in Acute and Chronic Myeloid

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Qian Xiong

2014-04-01

Full Text Available Myeloid leukemias are highly diverse diseases and have been shown to be associated with microRNA (miRNA expression aberrations. The present study involved an in-depth miRNome analysis of two human acute myeloid leukemia (AML cell lines, HL-60 and THP-1, and one human chronic myeloid leukemia (CML cell line, K562, via massively parallel signature sequencing. mRNA expression profiles of these cell lines that were established previously in our lab facilitated an integrative analysis of miRNA and mRNA expression patterns. miRNA expression profiling followed by differential expression analysis and target prediction suggested numerous miRNA signatures in AML and CML cell lines. Some miRNAs may act as either tumor suppressors or oncomiRs in AML and CML by targeting key genes in AML and CML pathways. Expression patterns of cell type-specific miRNAs could partially reflect the characteristics of K562, HL-60 and THP-1 cell lines, such as actin filament-based processes, responsiveness to stimulus and phagocytic activity. miRNAs may also regulate myeloid differentiation, since they usually suppress differentiation regulators. Our study provides a resource to further investigate the employment of miRNAs in human leukemia subtyping, leukemogenesis and myeloid development. In addition, the distinctive miRNA signatures may be potential candidates for the clinical diagnosis, prognosis and treatment of myeloid leukemias.

Targeting Myeloid-Derived Suppressor Cells to Bypass Tumor-Induced Immunosuppression

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Viktor Fleming

2018-03-01

Full Text Available The immune system has many sophisticated mechanisms to balance an extensive immune response. Distinct immunosuppressive cells could protect from excessive tissue damage and autoimmune disorders. Tumor cells take an advantage of those immunosuppressive mechanisms and establish a strongly immunosuppressive tumor microenvironment (TME, which inhibits antitumor immune responses, supporting the disease progression. Myeloid-derived suppressor cells (MDSC play a crucial role in this immunosuppressive TME. Those cells represent a heterogeneous population of immature myeloid cells with a strong immunosuppressive potential. They inhibit an antitumor reactivity of T cells and NK cells. Furthermore, they promote angiogenesis, establish pre-metastatic niches, and recruit other immunosuppressive cells such as regulatory T cells. Accumulating evidences demonstrated that the enrichment and activation of MDSC correlated with tumor progression, recurrence, and negative clinical outcome. In the last few years, various preclinical studies and clinical trials targeting MDSC showed promising results. In this review, we discuss different therapeutic approaches on MDSC targeting to overcome immunosuppressive TME and enhance the efficiency of current tumor immunotherapies.

Two-dimensional analysis of metabolically and cell surface radiolabeled proteins of some human lymphoid and myeloid leukemia cell lines. II. Glycosylated and phosphorylated proteins

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Chorvath, B; Duraj, J; Sedlak, J; Pleskova, I

1986-01-01

Cell surface glycoproteins, radiolabelled by the sodium metaperiodate/tritiated borohydride technique, and cell phosphoproteins, metabolically radiolabelled with /sup 32/P-orthophosphate were analyzed by two-dimensional electrophoretic analysis in some myeloid and lymphoid leukemia cell lines. Some markedly expressed major glycoproteins were predominant in some of the cell lines (such as 95k and 100k glycoproteins with marked charge heterogeneity in non-T, non-B acute lymphoblastic leukemia cell lines NALM 6 and NALM 16), but markedly quantitatively reduced in other examined cell lines, such as lymphoblastoid cell line UHKT 34/2. /sup 32/P-orthophosphate radiolabelled phosphoprotein two-dimensional patterns of the examined lymphoid leukemia cell lines were essentially similar, with some minor differences, in examined lymphoid and myeloid leukemia cell lines, such as marked expression of a series of large phosphoproteins in the molecular weight range 80-100k in lymphoid cell lines and almost complete absence of these phosphoproteins on the examined myeloid leukemia cell lines. Another configuration of acidic phosphoproteins (30-35k) exhibited individual cell line variability and differences between both individual myeloid leukemia cell lines and between the lymphoid and myeloid cell lines examined. (author) 2 figs., 15 refs.

An Immature Myeloid/Myeloid-Suppressor Cell Response Associated with Necrotizing Inflammation Mediates Lethal Pulmonary Tularemia.

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Sivakumar Periasamy

2016-03-01

Full Text Available Inhalation of Francisella tularensis (Ft causes acute and fatal pneumonia. The lung cytokine milieu favors exponential Ft replication, but the mechanisms underlying acute pathogenesis and death remain unknown. Evaluation of the sequential and systemic host immune response in pulmonary tularemia reveals that in contrast to overwhelming bacterial burden or cytokine production, an overt innate cellular response to Ft drives tissue pathology and host mortality. Lethal infection with Ft elicits medullary and extra-medullary myelopoiesis supporting recruitment of large numbers of immature myeloid cells and MDSC to the lungs. These cells fail to mature and die, leading to subsequent necrotic lung damage, loss of pulmonary function, and host death that is partially dependent upon immature Ly6G+ cells. Acceleration of this process may account for the rapid lethality seen with Ft SchuS4. In contrast, during sub-lethal infection with Ft LVS the pulmonary cellular response is characterized by a predominance of mature neutrophils and monocytes required for protection, suggesting a required threshold for lethal bacterial infection. Further, eliciting a mature phagocyte response provides transient, but dramatic, innate protection against Ft SchuS4. This study reveals that the nature of the myeloid cell response may be the primary determinant of host mortality versus survival following Francisella infection.

An Immature Myeloid/Myeloid-Suppressor Cell Response Associated with Necrotizing Inflammation Mediates Lethal Pulmonary Tularemia

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Periasamy, Sivakumar; Avram, Dorina; McCabe, Amanda; MacNamara, Katherine C.; Sellati, Timothy J.; Harton, Jonathan A.

2016-01-01

Inhalation of Francisella tularensis (Ft) causes acute and fatal pneumonia. The lung cytokine milieu favors exponential Ft replication, but the mechanisms underlying acute pathogenesis and death remain unknown. Evaluation of the sequential and systemic host immune response in pulmonary tularemia reveals that in contrast to overwhelming bacterial burden or cytokine production, an overt innate cellular response to Ft drives tissue pathology and host mortality. Lethal infection with Ft elicits medullary and extra-medullary myelopoiesis supporting recruitment of large numbers of immature myeloid cells and MDSC to the lungs. These cells fail to mature and die, leading to subsequent necrotic lung damage, loss of pulmonary function, and host death that is partially dependent upon immature Ly6G+ cells. Acceleration of this process may account for the rapid lethality seen with Ft SchuS4. In contrast, during sub-lethal infection with Ft LVS the pulmonary cellular response is characterized by a predominance of mature neutrophils and monocytes required for protection, suggesting a required threshold for lethal bacterial infection. Further, eliciting a mature phagocyte response provides transient, but dramatic, innate protection against Ft SchuS4. This study reveals that the nature of the myeloid cell response may be the primary determinant of host mortality versus survival following Francisella infection. PMID:27015566

Myeloid Sarcoma after Allogenic Stem Cell Transplantation for Acute Myeloid Leukemia: Successful Consolidation Treatment Approaches in Two Patients

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Silje Johansen

2018-01-01

Full Text Available Myeloid sarcoma is an extramedullary (EM manifestation (i.e., manifestation outside the bone marrow of acute myeloid leukemia (AML; it is assumed to be relatively uncommon and can be the only manifestation of leukemia relapse after allogenic stem cell transplantation (allo-SCT. An EM sarcoma can manifest in any part of the body, although preferentially manifesting in immunological sanctuary sites as a single or multiple tumors. The development of myeloid sarcoma after allo-SCT is associated with certain cytogenetic abnormalities, developing of graft versus host disease (GVHD, and treatment with donor lymphocytes infusion (DLI. It is believed that posttransplant myeloid sarcomas develop because the EM sites evade immune surveillance. We present two patients with EM myeloid sarcoma in the breast and epipharynx, respectively, as the only manifestation of leukemia relapse. Both patients were treated with a combination of local and systemic therapy, with successfully longtime disease-free survival. Based on these two case reports, we give an updated review of the literature and discuss the pathogenesis, diagnosis, and treatment of EM sarcoma as the only manifestation of AML relapse after allo-SCT. There are no standard guidelines for the treatment of myeloid sarcomas in allotransplant recipients. In our opinion, the treatment of these patients needs to be individualized and should include local treatment (i.e., radiotherapy combined with systemic therapy (i.e., chemotherapy, immunotherapy, DLI, or retransplantation. The treatment has to consider both the need for sufficient antileukemic efficiency versus the risk of severe complications due to cumulative toxicity.

Proliferation and Differentiation of Murine Myeloid Precursor 32D/G-CSF-R Cells

Czech Academy of Sciences Publication Activity Database

Zjablovskaja, Polina; Daněk, Petr; Kardošová, Miroslava; Alberich-Jorda, Meritxell

č. 132 (2018), č. článku e57033. ISSN 1940-087X R&D Projects: GA ČR GA15-03796S Institutional support: RVO:68378050 Keywords : 32D/G-CSF-R cells * murine myeloid precursor cells * liquid culture * differentiation * neutrophils * proliferation * cytokines * IL-3 * G-CSF Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.232, year: 2016

The Role and Potential Therapeutic Application of Myeloid-Derived Suppressor Cells in Allo- and Autoimmunity

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Qi Zhang

2015-01-01

Full Text Available Myeloid-derived suppressor cells (MDSCs are a heterogeneous population of cells that consists of myeloid progenitor cells and immature myeloid cells. They have been identified as a cell population that may affect the activation of CD4+ and CD8+ T-cells to regulate the immune response negatively, which makes them attractive targets for the treatment of transplantation and autoimmune diseases. Several studies have suggested the potential suppressive effect of MDSCs on allo- and autoimmune responses. Conversely, MDSCs have also been found at various stages of differentiation, accumulating during pathological situations, not only during tumor development but also in a variety of inflammatory immune responses, bone marrow transplantation, and some autoimmune diseases. These findings appear to be contradictory. In this review, we summarize the roles of MDSCs in different transplantation and autoimmune diseases models as well as the potential to target these cells for therapeutic benefit.

Blimp-1 impairs T cell function via upregulation of TIGIT and PD-1 in patients with acute myeloid leukemia.

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Zhu, Liuluan; Kong, Yaxian; Zhang, Jianhong; Claxton, David F; Ehmann, W Christopher; Rybka, Witold B; Palmisiano, Neil D; Wang, Ming; Jia, Bei; Bayerl, Michael; Schell, Todd D; Hohl, Raymond J; Zeng, Hui; Zheng, Hong

2017-06-19

T cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif (ITIM) domain (TIGIT) and programmed cell death protein 1 (PD-1) are important inhibitory receptors that associate with T cell exhaustion in acute myeloid leukemia (AML). In this study, we aimed to determine the underlying transcriptional mechanisms regulating these inhibitory pathways. Specifically, we investigated the role of transcription factor B lymphocyte-induced maturation protein 1 (Blimp-1) in T cell response and transcriptional regulation of TIGIT and PD-1 in AML. Peripheral blood samples collected from patients with AML were used in this study. Blimp-1 expression was examined by flow cytometry. The correlation of Blimp-1 expression to clinical characteristics of AML patients was analyzed. Phenotypic and functional studies of Blimp-1-expressing T cells were performed using flow cytometry-based assays. Luciferase reporter assays and ChIP assays were applied to assess direct binding and transcription activity of Blimp-1. Using siRNA to silence Blimp-1, we further elucidated the regulatory role of Blimp-1 in the TIGIT and PD-1 expression and T cell immune response. Blimp-1 expression is elevated in T cells from AML patients. Consistent with exhaustion, Blimp-1 + T cells upregulate multiple inhibitory receptors including PD-1 and TIGIT. In addition, they are functionally impaired manifested by low cytokine production and decreased cytotoxicity capacity. Importantly, the functional defect is reversed by inhibition of Blimp-1 via siRNA knockdown. Furthermore, Blimp-1 binds to the promoters of PD-1 and TIGIT and positively regulates their expression. Our study demonstrates an important inhibitory effect of Blimp-1 on T cell response in AML; thus, targeting Blimp-1 and its regulated molecules to improve the immune response may provide effective leukemia therapeutics.

Blimp-1 impairs T cell function via upregulation of TIGIT and PD-1 in patients with acute myeloid leukemia

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Liuluan Zhu

2017-06-01

Full Text Available Abstract Background T cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif (ITIM domain (TIGIT and programmed cell death protein 1 (PD-1 are important inhibitory receptors that associate with T cell exhaustion in acute myeloid leukemia (AML. In this study, we aimed to determine the underlying transcriptional mechanisms regulating these inhibitory pathways. Specifically, we investigated the role of transcription factor B lymphocyte-induced maturation protein 1 (Blimp-1 in T cell response and transcriptional regulation of TIGIT and PD-1 in AML. Methods Peripheral blood samples collected from patients with AML were used in this study. Blimp-1 expression was examined by flow cytometry. The correlation of Blimp-1 expression to clinical characteristics of AML patients was analyzed. Phenotypic and functional studies of Blimp-1-expressing T cells were performed using flow cytometry-based assays. Luciferase reporter assays and ChIP assays were applied to assess direct binding and transcription activity of Blimp-1. Using siRNA to silence Blimp-1, we further elucidated the regulatory role of Blimp-1 in the TIGIT and PD-1 expression and T cell immune response. Results Blimp-1 expression is elevated in T cells from AML patients. Consistent with exhaustion, Blimp-1+ T cells upregulate multiple inhibitory receptors including PD-1 and TIGIT. In addition, they are functionally impaired manifested by low cytokine production and decreased cytotoxicity capacity. Importantly, the functional defect is reversed by inhibition of Blimp-1 via siRNA knockdown. Furthermore, Blimp-1 binds to the promoters of PD-1 and TIGIT and positively regulates their expression. Conclusions Our study demonstrates an important inhibitory effect of Blimp-1 on T cell response in AML; thus, targeting Blimp-1 and its regulated molecules to improve the immune response may provide effective leukemia therapeutics.

Monocytes from cystic fibrosis patients are locked in an LPS tolerance state: down-regulation of TREM-1 as putative underlying mechanism.

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Carlos del Fresno

Full Text Available Cystic Fibrosis (CF is an inherited pleiotropic disease that results from abnormalities in the gene that codes for the chloride channel, Cystic Fibrosis Transmembrane Conductance Regulator (CFTR. CF patients are frequently colonized by several pathogens, but the mechanisms that allow colonization in spite of apparently functional immune systems are incompletely understood. In this paper we show that blood peripheral monocytes isolated from CF patients are found in an endotoxin tolerance state, yet this is not due to a deficient TLR activation. On the other hand, levels of the amplifier of inflammatory responses, TREM-1 (Triggering Receptor Expressed on Myeloid cells, are notably down-regulated in monocytes from patients, in comparison to those extracted from healthy volunteers. Furthermore, the soluble form of TREM-1 (sTREM-1 was not detected in the sera of patients. Additionally, and in strict contrast to patients who suffer from Chronic Obstructive Pulmonary Disease (COPD, CF monocytes challenged ex vivo with LPS neither up-regulated membrane-anchored TREM-1 nor sTREM-1. Finally, similar levels of PGE(2 expression and p65 translocation into the nucleus were found in both patients and healthy volunteers, thus suggesting that TREM-1 regulation is neither controlled by PGE(2 levels nor by p65 activation in this case. However, PU.1 translocation into the nucleus was significantly higher in CF monocytes than in controls, suggesting a role for this transcription factor in the control of TREM-1 expression. We conclude that down-regulation of TREM-1 expression in cystic fibrosis patients is at least partly responsible for the endotoxin tolerance state in which their monocytes are locked.

Reactive oxygen species activate differentiation gene transcription of acute myeloid leukemia cells via the JNK/c-JUN signaling pathway.

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Lam, Chung Fan; Yeung, Hoi Ting; Lam, Yuk Man; Ng, Ray Kit

2018-05-01

Reactive oxygen species (ROS) and altered cellular redox status are associated with many malignancies. Acute myeloid leukemia (AML) cells are maintained at immature state by differentiation blockade, which involves deregulation of transcription factors in myeloid differentiation. AML cells can be induced to differentiate by phorbol-12-myristate-13-acetate (PMA), which possesses pro-oxidative activity. However, the signaling events mediated by ROS in the activation of transcriptional program during AML differentiation has not been fully elucidated. Here, we investigated AML cell differentiation by treatment with PMA and ROS scavenger N-acetyl-l-cysteine (NAC). We observed elevation of intracellular ROS level in the PMA-treated AML cells, which correlated with differentiated cell morphology and increased CD11b + mature cell population. The effect of PMA can be abolished by NAC co-treatment, supporting the involvement of ROS in the process. Moreover, we demonstrated that short ROS elevation mediated cell cycle arrest, but failed to activate myeloid gene transcription; whereas prolonged ROS elevation activated JNK/c-JUN signaling pathway. Inhibition of JNK suppressed the expression of key myeloid transcriptional regulators c-JUN, SPI-1 and MAFB, and prevented AML cells from undergoing terminal differentiation. These findings provide new insights into the crucial role of JNK/c-Jun signaling pathway in the activation of transcriptional program during ROS-mediated AML differentiation. Copyright © 2018 Elsevier Ltd. All rights reserved.

Responses of the Murine Myeloid Colony-Forming Cell to Ansamycin Antibiotics

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Horoszewicz, Julius S.; Carter, William A.

1974-01-01

The in vitro susceptibility of murine myeloid colony-forming cells to the antiproliferative activities of three ansamycin antibiotics was determined. These cells were found to be 10- to 40-fold more susceptible than the corresponding human ones. PMID:4151701

CD40 dependent exacerbation of immune mediated hepatitis by hepatic CD11b+ Gr-1+ myeloid derived suppressor cells in tumor bearing mice

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Kapanadze, Tamar; Medina-Echeverz, José; Gamrekelashvili, Jaba; Weiss, Jonathan M.; Wiltrout, Robert H.; Kapoor, Veena; Hawk, Nga; Terabe, Masaki; Berzofsky, Jay A.; Manns, Michael P.; Wang, Ena; Marincola, Francesco M.; Korangy, Firouzeh; Greten, Tim F.

2015-01-01

Immunosuppressive CD11b+Gr-1+ myeloid-derived suppressor cells (MDSC) accumulate in the livers of tumor-bearing mice. We studied hepatic MDSC in two murine models of immune mediated hepatitis. Unexpectedly, treatment of tumor bearing mice with Concanavalin A or α-Galactosylceramide resulted in increased ALT and AST serum levels in comparison to tumor free mice. Adoptive transfer of hepatic MDSC into naïve mice exacerbated Concanavalin A induced liver damage. Hepatic CD11b+Gr-1+ cells revealed a polarized pro-inflammatory gene signature after Concanavalin A treatment. An interferon gamma- dependent up-regulation of CD40 on hepatic CD11b+Gr-1+ cells along with an up-regulation of CD80, CD86, and CD1d after Concanavalin A treatment was observed. Concanavalin A treatment resulted in a loss of suppressor function by tumor-induced CD11b+Gr-1+ MDSC as well as enhanced reactive oxygen species-mediated hepatotoxicity. CD40 knockdown in hepatic MDSC led to increased arginase activity upon Concanavalin A treatment and lower ALT/AST serum levels. Finally, blockade of arginase activity in Cd40−/− tumor-induced myeloid cells resulted in exacerbation of hepatitis and increased reactive oxygen species production in vivo. Our findings indicate that in a setting of acute hepatitis, tumor-induced hepatic MDSC act as pro-inflammatory immune effector cells capable of killing hepatocytes in a CD40-dependent manner. PMID:25616156

New biomarkers for sepsis

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Li-xin XIE

2013-01-01

Full Text Available There is a higher sepsis rate in the intensive care unit (ICU patients, which is one of the most important causes for patient death, but the sepsis lacks specific clinical manifestations. Exploring sensitive and specific molecular markers for infection that accurately reflect infection severity and prognosis is very clinically important. In this article, based on our previous study, we introduce some new biomarkers with high sensitivity and specificity for the diagnosis and predicting the prognosis and severity of sepsis. Increase of serum soluble(s triggering receptor expressed on myeloid cells-1 (sTREM-1 suggests a poor prognosis of septic patients, and changes of locus rs2234237 of sTREM-1 may be the one of important mechanisms. Additionally, urine sTREM-1 can provide an early warning of possible secondary acute kidney injury (AKI in sepsis patients. Serum sCD163 level was found to be a more important factor than procalcitonin (PCT and C-reactive protein (CRP in prognosis of sepsis, especially severe sepsis. Moreover, urine sCD163 also shows excellent performance in the diagnosis of sepsis and sepsis-associated AKI. Circulating microRNAs, such as miR-150, miR-297, miR-574-5p, miR -146a , miR-223, miR -15a and miR-16, also play important roles in the evaluation of status of septic patients. In the foreseeable future, newly-emerging technologies, including proteomics, metabonomics and trans-omics, may exert profound effects on the discovery of valuable biomarkers for sepsis.

Concurrent targeting Akt and sphingosine kinase 1 by A-674563 in acute myeloid leukemia cells

International Nuclear Information System (INIS)

Xu, Lin; Zhang, Yanan; Gao, Meng; Wang, Guangping; Fu, Yunfeng

2016-01-01

Akt signaling plays a pivotal role in acute myeloid leukemia (AML) development and progression. In the present study, we evaluated the potential anti-AML activity by a novel Akt kinase inhibitor A-674563. Our results showed that A-674563 dose-dependently inhibited survival and proliferation of U937 AML cells and six lines of human AML progenitor cells, yet sparing human peripheral blood mononuclear leukocytes (PBMCs). A-674563 activated caspase-3/9 and apoptosis in the AML cells. Reversely, the pan-caspase inhibitor z-VAD-CHO dramatically alleviated A-674563-induced AML cell apoptosis and cytotoxicity. For the molecular study, we showed that A-674563 blocked Akt activation in U937 cells and human AML progenitor cells. Further, A-674563 decreased sphingosine kinase 1 (SphK1) activity in above AML cells to deplete pro-survival sphingosine-1-phosphate (S1P) and boost pro-apoptotic ceramide production. Such an effect on SphK1 signaling by A-674563 appeared independent of Akt blockage. Significantly, K6PC-5, a novel SphK1 activator, or supplement with S1P attenuated A-674563-induced ceramide production, and subsequent U937 cell death and apoptosis. Importantly, intraperitoneal injection of A-674563 at well-tolerated doses suppressed U937 leukemic xenograft tumor growth in nude mice, whiling significantly improving the animal survival. The results of the current study demonstrate that A-674563 exerts potent anti-leukemic activity in vitro and in vivo, possibly via concurrent targeting Akt and SphK1 signalings. - Highlights: • A-674563 is cytotoxic and anti-proliferative in U937 and AML progenitor cells. • A-674563 activates caspase-3/9 and apoptosis in U937 and AML progenitor cells. • Whiling blocking Akt, A-674563 manipulates other signalings in AML cells. • A-674563 inhibits SphK1 activity in AML cells, independent of Akt blockage. • A-674563 injection inhibits U937 xenograft in vivo growth, and improves mice survival.

Concurrent targeting Akt and sphingosine kinase 1 by A-674563 in acute myeloid leukemia cells

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Xu, Lin [Xiangya Hospital, Central South University, Changsha (China); Shaoyang Central Hospital, Hunan Province (China); Zhang, Yanan; Gao, Meng [The Third Xiangya Hospital, Central South University, Changsha, 410013 (China); Wang, Guangping, E-mail: wangguangping45@sina.com [Xiangya Hospital, Central South University, Changsha (China); Fu, Yunfeng, E-mail: fuyunfeng33163@163.com [The Third Xiangya Hospital, Central South University, Changsha, 410013 (China)

2016-04-15

Akt signaling plays a pivotal role in acute myeloid leukemia (AML) development and progression. In the present study, we evaluated the potential anti-AML activity by a novel Akt kinase inhibitor A-674563. Our results showed that A-674563 dose-dependently inhibited survival and proliferation of U937 AML cells and six lines of human AML progenitor cells, yet sparing human peripheral blood mononuclear leukocytes (PBMCs). A-674563 activated caspase-3/9 and apoptosis in the AML cells. Reversely, the pan-caspase inhibitor z-VAD-CHO dramatically alleviated A-674563-induced AML cell apoptosis and cytotoxicity. For the molecular study, we showed that A-674563 blocked Akt activation in U937 cells and human AML progenitor cells. Further, A-674563 decreased sphingosine kinase 1 (SphK1) activity in above AML cells to deplete pro-survival sphingosine-1-phosphate (S1P) and boost pro-apoptotic ceramide production. Such an effect on SphK1 signaling by A-674563 appeared independent of Akt blockage. Significantly, K6PC-5, a novel SphK1 activator, or supplement with S1P attenuated A-674563-induced ceramide production, and subsequent U937 cell death and apoptosis. Importantly, intraperitoneal injection of A-674563 at well-tolerated doses suppressed U937 leukemic xenograft tumor growth in nude mice, whiling significantly improving the animal survival. The results of the current study demonstrate that A-674563 exerts potent anti-leukemic activity in vitro and in vivo, possibly via concurrent targeting Akt and SphK1 signalings. - Highlights: • A-674563 is cytotoxic and anti-proliferative in U937 and AML progenitor cells. • A-674563 activates caspase-3/9 and apoptosis in U937 and AML progenitor cells. • Whiling blocking Akt, A-674563 manipulates other signalings in AML cells. • A-674563 inhibits SphK1 activity in AML cells, independent of Akt blockage. • A-674563 injection inhibits U937 xenograft in vivo growth, and improves mice survival.

Activated T cells sustain myeloid-derived suppressor cell-mediated immune suppression

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Damuzzo, Vera; Francescato, Samuela; Pozzuoli, Assunta; Berizzi, Antonio; Mocellin, Simone; Rossi, Carlo Riccardo; Bronte, Vincenzo; Mandruzzato, Susanna

2016-01-01

The expansion of myeloid derived suppressor cells (MDSCs), a suppressive population able to hamper the immune response against cancer, correlates with tumor progression and overall survival in several cancer types. We have previously shown that MDSCs can be induced in vitro from precursors present in the bone marrow and observed that these cells are able to actively proliferate in the presence of activated T cells, whose activation level is critical to drive the suppressive activity of MDSCs. Here we investigated at molecular level the mechanisms involved in the interplay between MDSCs and activated T cells. We found that activated T cells secrete IL-10 following interaction with MDSCs which, in turn, activates STAT3 phosphorylation on MDSCs then leading to B7-H1 expression. We also demonstrated that B7-H1+ MDSCs are responsible for immune suppression through a mechanism involving ARG-1 and IDO expression. Finally, we show that the expression of ligands B7-H1 and MHC class II both on in vitro-induced MDSCs and on MDSCs in the tumor microenvironment of cancer patients is paralleled by an increased expression of their respective receptors PD-1 and LAG-3 on T cells, two inhibitory molecules associated with T cell dysfunction. These findings highlight key molecules and interactions responsible for the extensive cross-talk between MDSCs and activated T cells that are at the basis of immune suppression. PMID:26700461

Peripherally administered nanoparticles target monocytic myeloid cells, secondary lymphoid organs and tumors in mice.

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Kourtis, Iraklis C; Hirosue, Sachiko; de Titta, Alexandre; Kontos, Stephan; Stegmann, Toon; Hubbell, Jeffrey A; Swartz, Melody A

2013-01-01

Nanoparticles have been extensively developed for therapeutic and diagnostic applications. While the focus of nanoparticle trafficking in vivo has traditionally been on drug delivery and organ-level biodistribution and clearance, recent work in cancer biology and infectious disease suggests that targeting different cells within a given organ can substantially affect the quality of the immunological response. Here, we examine the cell-level biodistribution kinetics after administering ultrasmall Pluronic-stabilized poly(propylene sulfide) nanoparticles in the mouse. These nanoparticles depend on lymphatic drainage to reach the lymph nodes and blood, and then enter the spleen rather than the liver, where they interact with monocytes, macrophages and myeloid dendritic cells. They were more readily taken up into lymphatics after intradermal (i.d.) compared to intramuscular administration, leading to ∼50% increased bioavailability in blood. When administered i.d., their distribution favored antigen-presenting cells, with especially strong targeting to myeloid cells. In tumor-bearing mice, the monocytic and the polymorphonuclear myeloid-derived suppressor cell compartments were efficiently and preferentially targeted, rendering this nanoparticulate formulation potentially useful for reversing the highly suppressive activity of these cells in the tumor stroma.

Peripherally administered nanoparticles target monocytic myeloid cells, secondary lymphoid organs and tumors in mice.

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Iraklis C Kourtis

Full Text Available Nanoparticles have been extensively developed for therapeutic and diagnostic applications. While the focus of nanoparticle trafficking in vivo has traditionally been on drug delivery and organ-level biodistribution and clearance, recent work in cancer biology and infectious disease suggests that targeting different cells within a given organ can substantially affect the quality of the immunological response. Here, we examine the cell-level biodistribution kinetics after administering ultrasmall Pluronic-stabilized poly(propylene sulfide nanoparticles in the mouse. These nanoparticles depend on lymphatic drainage to reach the lymph nodes and blood, and then enter the spleen rather than the liver, where they interact with monocytes, macrophages and myeloid dendritic cells. They were more readily taken up into lymphatics after intradermal (i.d. compared to intramuscular administration, leading to ∼50% increased bioavailability in blood. When administered i.d., their distribution favored antigen-presenting cells, with especially strong targeting to myeloid cells. In tumor-bearing mice, the monocytic and the polymorphonuclear myeloid-derived suppressor cell compartments were efficiently and preferentially targeted, rendering this nanoparticulate formulation potentially useful for reversing the highly suppressive activity of these cells in the tumor stroma.

Myeloid cell leukemia-1 (Mc1-1 is a candidate target gene of hypoxia-inducible factor-1 (HIF-1 in the testis

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Palladino Michael A

2012-12-01

Full Text Available Abstract Background Spermatic cord torsion can lead to testis ischemia (I and subsequent ischemia-reperfusion (I/R causing germ cell-specific apoptosis. Previously, we demonstrated that the hypoxia-inducible factor-1 (HIF-1 transcription factor, a key regulator of physiological responses to hypoxia, is abundant in Leydig cells in normoxic and ischemic testes. We hypothesize that testicular HIF-1 activates the expression of antiapoptotic target genes to protect Leydig cells from apoptosis. In silico analysis of testis genes containing a consensus hypoxia response element (HRE, 5’-RCGTG-3’ identified myeloid cell leukemia-1 (Mcl-1 as a potential HIF-1 target gene. The purpose of this study was to determine whether HIF-1 shows DNA-binding activity in normoxic and ischemic testes and whether Mcl-1 is a target gene of testicular HIF-1. Methods The testicular HIF-1 DNA-binding capacity was analyzed in vitro using a quantitative enzyme-linked immunosorbent assay (ELISA and electrophoretic mobility shift assays (EMSA. MCL-1 protein expression was evaluated by immunoblot analysis and immunohistochemistry. The binding of testicular HIF-1 to the Mcl-1 gene was examined via chromatin immunoprecipitation (ChIP analysis. Results The ELISA and EMSA assays demonstrated that testicular HIF-1 from normoxic and ischemic testes binds DNA equally strongly, suggesting physiological roles for HIF-1 in the normoxic testis, unlike most tissues in which HIF-1 is degraded under normoxic conditions and is only activated by hypoxia. MCL-1 protein was determined to be abundant in both normoxic and ischemic testes and expressed in Leydig cells. In a pattern identical to that of HIF-1 expression, the steady-state levels of MCL-1 were not significantly affected by I or I/R and MCL-1 co-localized with HIF-1α in Leydig cells. Chromatin immunoprecipitation (ChIP analysis using a HIF-1 antibody revealed sequences enriched for the Mcl-1 promoter. Conclusions The results

Refinement of 1p36 alterations not involving PRDM16 in myeloid and lymphoid malignancies.

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Francois P Duhoux

Full Text Available Fluorescence in situ hybridization was performed to characterize 81 cases of myeloid and lymphoid malignancies with cytogenetic 1p36 alterations not affecting the PRDM16 locus. In total, three subgroups were identified: balanced translocations (N = 27 and telomeric rearrangements (N = 15, both mainly observed in myeloid disorders; and unbalanced non-telomeric rearrangements (N = 39, mainly observed in lymphoid proliferations and frequently associated with a highly complex karyotype. The 1p36 rearrangement was isolated in 12 cases, mainly myeloid disorders. The breakpoints on 1p36 were more widely distributed than previously reported, but with identifiable rare breakpoint cluster regions, such as the TP73 locus. We also found novel partner loci on 1p36 for the known multi-partner genes HMGA2 and RUNX1. We precised the common terminal 1p36 deletion, which has been suggested to have an adverse prognosis, in B-cell lymphomas [follicular lymphomas and diffuse large B-cell lymphomas with t(14;18(q32;q21 as well as follicular lymphomas without t(14;18]. Intrachromosomal telomeric repetitive sequences were detected in at least half the cases of telomeric rearrangements. It is unclear how the latter rearrangements occurred and whether they represent oncogenic events or result from chromosomal instability during oncogenesis.

Biological Therapy in Treating Patients With Advanced Myelodysplastic Syndrome, Acute or Chronic Myeloid Leukemia, or Acute Lymphoblastic Leukemia Who Are Undergoing Stem Cell Transplantation

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2017-03-27

Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); B-cell Adult Acute Lymphoblastic Leukemia; B-cell Childhood Acute Lymphoblastic Leukemia; Childhood Chronic Myelogenous Leukemia; Childhood Myelodysplastic Syndromes; Chronic Myelomonocytic Leukemia; Essential Thrombocythemia; Polycythemia Vera; Previously Treated Myelodysplastic Syndromes; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Acute Myeloid Leukemia; Recurrent Childhood Acute Lymphoblastic Leukemia; Recurrent Childhood Acute Myeloid Leukemia; Refractory Anemia With Excess Blasts; Refractory Anemia With Excess Blasts in Transformation; Relapsing Chronic Myelogenous Leukemia; Secondary Acute Myeloid Leukemia; T-cell Adult Acute Lymphoblastic Leukemia; T-cell Childhood Acute Lymphoblastic Leukemia

Systemic agonistic anti-CD40 treatment of tumor bearing mice modulates hepatic myeloid suppressive cells and causes immune-mediated liver damage

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Medina-Echeverz, José; Ma, Chi; Duffy, Austin; Eggert, Tobias; Hawk, Nga; Kleiner, David E.; Korangy, Firouzeh; Greten, Tim F.

2015-01-01

Immune stimulatory monoclonal antibodies are currently evaluated as anti tumor agents. Although overall toxicity appears to be moderate, liver toxicities have been reported and are not completely understood. We studied the effect of systemic CD40 antibody treatment on myeloid cells in spleen and liver. Naïve and tumor-bearing mice were treated systemically with agonistic anti-CD40 antibody. Immune cell subsets in liver and spleen, serum transaminases and liver histologies were analyzed after antibody administration. Nox2−/−, Cd40−/− as well as bone marrow chimeric mice were used to study the mechanism by which agonistic anti-CD40 mediates its effects in vivo. Suppressor function of murine and human tumor-induced myeloid derived suppressive cells was studied upon CD40 ligation. Agonistic CD40 antibody caused liver damage within 24 hours after injection in two unrelated tumor models and mice strains. Using bone marrow chimeras we demonstrated that CD40 antibody-induced hepatitis in tumor-bearing mice was dependent on the presence of CD40-expressing hematopoietic cells. Agonistic CD40 ligation-dependent liver damage was induced by the generation of reactive oxygen species. Furthermore, agonistic CD40 antibody resulted in increased CD80 and CD40 positive liver CD11b+Gr-1+ immature myeloid cells. CD40 ligation on tumor-induced murine and human CD14+HLA-DRlow PBMC from cancer patients reduced their immune suppressor function. Collectively, agonistic CD40 antibody treatment activated tumor-induced, myeloid cells, caused myeloid dependent hepatotoxicity and ameliorated the suppressor function of murine and human MDSC. Collectively, our data suggests that CD40 may mature immunosuppressive myeloid cells and thereby cause liver damage in mice with an accumulation of tumor-induced hepatic MDSC. PMID:25637366

spib is required for primitive myeloid development in Xenopus.

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Costa, Ricardo M B; Soto, Ximena; Chen, Yaoyao; Zorn, Aaron M; Amaya, Enrique

2008-09-15

Vertebrate blood formation occurs in 2 spatially and temporally distinct waves, so-called primitive and definitive hematopoiesis. Although definitive hematopoiesis has been extensively studied, the development of primitive myeloid blood has received far less attention. In Xenopus, primitive myeloid cells originate in the anterior ventral blood islands, the equivalent of the mammalian yolk sac, and migrate out to colonize the embryo. Using fluorescence time-lapse video microscopy, we recorded the migratory behavior of primitive myeloid cells from their birth. We show that these cells are the first blood cells to differentiate in the embryo and that they are efficiently recruited to embryonic wounds, well before the establishment of a functional vasculature. Furthermore, we isolated spib, an ETS transcription factor, specifically expressed in primitive myeloid precursors. Using spib antisense morpholino knockdown experiments, we show that spib is required for myeloid specification, and, in its absence, primitive myeloid cells retain hemangioblast-like characteristics and fail to migrate. Thus, we conclude that spib sits at the top of the known genetic hierarchy that leads to the specification of primitive myeloid cells in amphibians.

Clinical impact of the immunome in lymphoid malignancies: the role of Myeloid-Derived Suppressor Cells

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Calogero eVetro

2015-05-01

Full Text Available The better definition of the mutual sustainment between neoplastic cells and immune system has been translated from the bench to the bedside acquiring value as prognostic factor. Additionally, it represents a promising tool for improving therapeutic strategies. In this context, myeloid-derived suppressor cells have gained a central role in tumor developing with consequent therapeutic implications. In this review, we will focus on the biological and clinical impact of the study of myeloid-derived suppressor cells in the settings of lymphoid malignancies.

Clinical activity of azacitidine in patients who relapse after allogeneic stem cell transplantation for acute myeloid leukemia

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Craddock, Charles; Labopin, Myriam; Robin, Marie

2016-01-01

Disease relapse is the most common cause of treatment failure after allogeneic stem cell transplantation for acute myeloid leukemia and myelodysplastic syndromes, yet treatment options for such patients remain extremely limited. Azacitidine is an important new therapy in high-risk myelodysplastic...... syndromes and acute myeloid leukemia but its role in patients who relapse post allograft has not been defined. We studied the tolerability and activity of azacitidine in 181 patients who relapsed after an allograft for acute myeloid leukemia (n=116) or myelodysplastic syndromes (n=65). Sixty-nine patients...... conclude that azacitidine represents an important new therapy in selected patients with acute myeloid leukemia/myelodysplastic syndromes who relapse after allogeneic stem cell transplantation. Prospective studies to confirm optimal treatment options in this challenging patient population are required....

Biologico-clinical significance of DNMT3A variants expression in acute myeloid leukemia.

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Lin, Na; Fu, Wei; Zhao, Chen; Li, Bixin; Yan, Xiaojing; Li, Yan

2017-12-09

DNA methyltransferase 3A (DNMT3A) catalyzes de novo DNA methylation and plays important roles in the pathogenesis of acute myeloid leukemia. However, the expression status of DNMT3A variants in acute myeloid leukemia remains obscure. This study aimed to assess the expression levels of alternative splicing of DNMT3A variants and explore their roles in acute myeloid leukemia (AML). DNMT3A variants gene expression were assessed, measuring their effects on cell proliferation. In addition, the expression of DNMT3A variants were evaluated in acute myeloid leukemia patients. Four DNMT3A variants were identified, with DNMT3A1 and DNMT3A2V found to be dominant in acute myeloid leukemia cell lines. Moreover, DNMT3A2V overexpression delayed cell proliferation; while, DNMT3A2V R882H mutation promoted cell proliferation. Further, DNMT3A1 and DNMT3A2V were detected in newly diagnosed acute myeloid leukemia (AML) patients and controls with non-malignant hematological disease, with DNMT3A2V significantly up-regulated in AML patients. The main transcript switched from DNMT3A1 to DNMT3A2V in some patients, especially the low risk group based on the NCCN 2016 guidelines. These findings suggest that DNMT3A1 and DNMT3A2V are the main variants in acute myeloid leukemia with different clinical association, and might play important roles in the pathophysiology of acute myeloid leukemia. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

SUMOylation of sPRDM16 promotes the progression of acute myeloid leukemia

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Dong, Song; Chen, Jieping

2015-01-01

In addition to genetic and epigenetic alteration, post-translational modification of proteins plays a critical role in the initiation, progression and maturation of acute myeloid leukemia (AML). The SUMOylation site of sPRDM16 at K568 was mutated to arginine by site-directed mutagenesis. THP-1 acute myeloid leukemia cells were transduced with a lentivirus containing wild type or K568 mutant sPRDM16. Proliferation, self-renewal and differentiation of transduced THP-1 cells were analyzed both in vitro cell culture and in mouse xenografts. Gene expression profiles were analyzed by RNA-seq. Overexpression of sPRDM16 promoted proliferation, enhanced self-renewal capacity, but inhibited differentiation of THP-1 acute myeloid leukemia cells. We further confirmed that K568 is a bona fide SUMOylation site on sPRDM16. Mutation of the sPRDM16 SUMOylation site at K568 partially abolished the capacity of sPRDM16 to promote proliferation and inhibit differentiation of acute myeloid leukemia cells both in vitro and in mouse xenografts. Furthermore, THP-1 cells overexpressing sPRDM16-K568R mutant exhibited a distinct gene expression profile from wild type sPRDM16 following incubation with PMA. Our results suggest that K568 SUMOylation of sPRDM16 plays an important role in the progression of acute myeloid leukemia

Myeloid malignancies: mutations, models and management

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Murati, Anne; Brecqueville, Mandy; Devillier, Raynier; Mozziconacci, Marie-Joelle; Gelsi-Boyer, Véronique; Birnbaum, Daniel

2012-01-01

Myeloid malignant diseases comprise chronic (including myelodysplastic syndromes, myeloproliferative neoplasms and chronic myelomonocytic leukemia) and acute (acute myeloid leukemia) stages. They are clonal diseases arising in hematopoietic stem or progenitor cells. Mutations responsible for these diseases occur in several genes whose encoded proteins belong principally to five classes: signaling pathways proteins (e.g. CBL, FLT3, JAK2, RAS), transcription factors (e.g. CEBPA, ETV6, RUNX1), epigenetic regulators (e.g. ASXL1, DNMT3A, EZH2, IDH1, IDH2, SUZ12, TET2, UTX), tumor suppressors (e.g. TP53), and components of the spliceosome (e.g. SF3B1, SRSF2). Large-scale sequencing efforts will soon lead to the establishment of a comprehensive repertoire of these mutations, allowing for a better definition and classification of myeloid malignancies, the identification of new prognostic markers and therapeutic targets, and the development of novel therapies. Given the importance of epigenetic deregulation in myeloid diseases, the use of drugs targeting epigenetic regulators appears as a most promising therapeutic approach

Growth Factor-Activated Stem Cell Circuits and Stromal Signals Cooperatively Accelerate Non-Integrated iPSC Reprogramming of Human Myeloid Progenitors

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Park, Tea Soon; Huo, Jeffrey S.; Peters, Ann; Talbot, C. Conover; Verma, Karan; Zimmerlin, Ludovic; Kaplan, Ian M.; Zambidis, Elias T.

2012-01-01

Nonviral conversion of skin or blood cells into clinically useful human induced pluripotent stem cells (hiPSC) occurs in only rare fractions (∼0.001%–0.5%) of donor cells transfected with non-integrating reprogramming factors. Pluripotency induction of developmentally immature stem-progenitors is generally more efficient than differentiated somatic cell targets. However, the nature of augmented progenitor reprogramming remains obscure, and its potential has not been fully explored for improving the extremely slow pace of non-integrated reprogramming. Here, we report highly optimized four-factor reprogramming of lineage-committed cord blood (CB) myeloid progenitors with bulk efficiencies of ∼50% in purified episome-expressing cells. Lineage-committed CD33+CD45+CD34− myeloid cells and not primitive hematopoietic stem-progenitors were the main targets of a rapid and nearly complete non-integrated reprogramming. The efficient conversion of mature myeloid populations into NANOG+TRA-1-81+ hiPSC was mediated by synergies between hematopoietic growth factor (GF), stromal activation signals, and episomal Yamanaka factor expression. Using a modular bioinformatics approach, we demonstrated that efficient myeloid reprogramming correlated not to increased proliferation or endogenous Core factor expressions, but to poised expression of GF-activated transcriptional circuits that commonly regulate plasticity in both hematopoietic progenitors and embryonic stem cells (ESC). Factor-driven conversion of myeloid progenitors to a high-fidelity pluripotent state was further accelerated by soluble and contact-dependent stromal signals that included an implied and unexpected role for Toll receptor-NFκB signaling. These data provide a paradigm for understanding the augmented reprogramming capacity of somatic progenitors, and reveal that efficient induced pluripotency in other cell types may also require extrinsic activation of a molecular framework that commonly regulates self

Hepatic ischemia and reperfusion injury in the absence of myeloid cell-derived COX-2 in mice.

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Sergio Duarte

Full Text Available Cyclooxygenase-2 (COX-2 is a mediator of hepatic ischemia and reperfusion injury (IRI. While both global COX-2 deletion and pharmacologic COX-2 inhibition ameliorate liver IRI, the clinical use of COX-2 inhibitors has been linked to increased risks of heart attack and stroke. Therefore, a better understanding of the role of COX-2 in different cell types may lead to improved therapeutic strategies for hepatic IRI. Macrophages of myeloid origin are currently considered to be important sources of the COX-2 in damaged livers. Here, we used a Cox-2flox conditional knockout mouse (COX-2-M/-M to examine the function of COX-2 expression in myeloid cells during liver IRI. COX-2-M/-M mice and their WT control littermates were subjected to partial liver ischemia followed by reperfusion. COX-2-M/-M macrophages did not express COX-2 upon lipopolysaccharide stimulation and COX-2-M/-M livers showed reduced levels of COX-2 protein post-IRI. Nevertheless, selective deletion of myeloid cell-derived COX-2 failed to ameliorate liver IRI; serum transaminases and histology were comparable in both COX-2-M/-M and WT mice. COX-2-M/-M livers, like WT livers, developed extensive necrosis, vascular congestion, leukocyte infiltration and matrix metalloproteinase-9 (MMP-9 expression post-reperfusion. In addition, myeloid COX-2 deletion led to a transient increase in IL-6 levels after hepatic reperfusion, when compared to controls. Administration of celecoxib, a selective COX-2 inhibitor, resulted in significantly improved liver function and histology in both COX-2-M/-M and WT mice post-reperfusion, providing evidence that COX-2-mediated liver IRI is caused by COX-2 derived from a source(s other than myeloid cells. In conclusion, these results support the view that myeloid COX-2, including myeloid-macrophage COX-2, is not responsible for the hepatic IRI phenotype.

Auger electron-emitting "1"1"1In-DTPA-NLS-CSL360 radioimmunoconjugates are cytotoxic to human acute myeloid leukemia (AML) cells displaying the CD123"+/CD131"− phenotype of leukemia stem cells

International Nuclear Information System (INIS)

Gao, Catherine; Leyton, Jeffrey V.; Schimmer, Aaron D.; Minden, Mark; Reilly, Raymond M.

2016-01-01

Chimeric IgG_1 monoclonal antibody CSL360 recognizes the CD123"+/CD131"− phenotype expressed by leukemic stem cells (LSC). Auger electron-emitting "1"1"1In-DTPA-NLS-CSL360 radioimmunoconjugates incorporating nuclear translocation sequence (NLS) peptides bound specifically to Raji cells transfected with CD123 and exhibited a K_D of 11 nmols/L in a competition receptor-binding assay using CD123-transfected CHO cells. "1"1"1In-DTPA-NLS-CSL360 was bound, internalized and transported to the nucleus of human AML-5 myeloid leukemia cells. The clonogenic survival of AML-5 cells was reduced by "1"1"1In-DTPA-NLS-CSL360 up to 3.7-fold. Isotype control "1"1"1In-DTPA-chIgG_1 was 2-fold less cytotoxic, and unlabeled CSL360, DTPA-NLS-CSL360 or free "1"1"1In acetate did not decrease cell survival. These results are promising for further evaluation of "1"1"1In-DTPA-NLS-CSL360 for Auger electron radioimmunotherapy of AML targeting the critical LSC subpopulation. - Highlights: • "1"1"1In-DTPA-NLS-CSL360 the CD123"+/CD131"− phenotype of leukemic stem cells (LSC). • "1"1"1In-DTPA-NLS-CSL360 was bound, internalized and imported into the nucleus of AML-5 leukemia cells. • "1"1"1In-DTPA-NLS-CSL360 reduced the clonogenic survival of AML-5 leukemia cells by 4-fold.

Myeloid HIF-1 is protective in Helicobacter pylori-mediated gastritis.

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Matak, Pavle; Heinis, Mylène; Mathieu, Jacques R R; Corriden, Ross; Cuvellier, Sylvain; Delga, Stéphanie; Mounier, Rémi; Rouquette, Alexandre; Raymond, Josette; Lamarque, Dominique; Emile, Jean-François; Nizet, Victor; Touati, Eliette; Peyssonnaux, Carole

2015-04-01

Helicobacter pylori infection triggers chronic inflammation of the gastric mucosa that may progress to gastric cancer. The hypoxia-inducible factors (HIFs) are the central mediators of cellular adaptation to low oxygen levels (hypoxia), but they have emerged recently as major transcriptional regulators of immunity and inflammation. No studies have investigated whether H. pylori affects HIF signaling in immune cells and a potential role for HIF in H. pylori-mediated gastritis. HIF-1 and HIF-2 expression was examined in human H. pylori-positive gastritis biopsies. Subsequent experiments were performed in naive and polarized bone marrow-derived macrophages from wild-type (WT) and myeloid HIF-1α-null mice (HIF-1(Δmyel)). WT and HIF-1(Δmyel) mice were inoculated with H. pylori by oral gavage and sacrificed 6 mo postinfection. HIF-1 was specifically expressed in macrophages of human H. pylori-positive gastritis biopsies. Macrophage HIF-1 strongly contributed to the induction of proinflammatory genes (IL-6, IL-1β) and inducible NO synthase in response to H. pylori. HIF-2 expression and markers of M2 macrophage differentiation were decreased in response to H. pylori. HIF-1(Δmyel) mice inoculated with H. pylori for 6 mo presented with a similar bacterial colonization than WT mice but, surprisingly, a global increase of inflammation, leading to a worsening of the gastritis, measured by an increased epithelial cell proliferation. In conclusion, myeloid HIF-1 is protective in H. pylori-mediated gastritis, pointing to the complex counterbalancing roles of innate immune and inflammatory phenotypes in driving this pathology. Copyright © 2015 by The American Association of Immunologists, Inc.

Natural Product Vibsanin A Induces Differentiation of Myeloid Leukemia Cells through PKC Activation.

Science.gov (United States)

Yu, Zu-Yin; Xiao, He; Wang, Li-Mei; Shen, Xing; Jing, Yu; Wang, Lin; Sun, Wen-Feng; Zhang, Yan-Feng; Cui, Yu; Shan, Ya-Jun; Zhou, Wen-Bing; Xing, Shuang; Xiong, Guo-Lin; Liu, Xiao-Lan; Dong, Bo; Feng, Jian-Nan; Wang, Li-Sheng; Luo, Qing-Liang; Zhao, Qin-Shi; Cong, Yu-Wen

2016-05-01

All-trans retinoic acid (ATRA)-based cell differentiation therapy has been successful in treating acute promyelocytic leukemia, a unique subtype of acute myeloid leukemia (AML). However, other subtypes of AML display resistance to ATRA-based treatment. In this study, we screened natural, plant-derived vibsane-type diterpenoids for their ability to induce differentiation of myeloid leukemia cells, discovering that vibsanin A potently induced differentiation of AML cell lines and primary blasts. The differentiation-inducing activity of vibsanin A was mediated through direct interaction with and activation of protein kinase C (PKC). Consistent with these findings, pharmacological blockade of PKC activity suppressed vibsanin A-induced differentiation. Mechanistically, vibsanin A-mediated activation of PKC led to induction of the ERK pathway and decreased c-Myc expression. In mouse xenograft models of AML, vibsanin A administration prolonged host survival and inhibited PKC-mediated inflammatory responses correlated with promotion of skin tumors in mice. Collectively, our results offer a preclinical proof of concept for vibsanin A as a myeloid differentiation-inducing compound, with potential application as an antileukemic agent. Cancer Res; 76(9); 2698-709. ©2016 AACR. ©2016 American Association for Cancer Research.

Cyanobacteria from Terrestrial and Marine Sources Contain Apoptogens Able to Overcome Chemoresistance in Acute Myeloid Leukemia Cells

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Liu, Liwei; Herfindal, Lars; Jokela, Jouni; Shishido, Tania Keiko; Wahlsten, Matti; Døskeland, Stein Ove; Sivonen, Kaarina

2014-01-01

In this study, we investigated forty cyanobacterial isolates from biofilms, gastropods, brackish water and symbiotic lichen habitats. Their aqueous and organic extracts were used to screen for apoptosis-inducing activity against acute myeloid leukemia cells. A total of 28 extracts showed cytotoxicity against rat acute myeloid leukemia (IPC-81) cells. The design of the screen made it possible to eliminate known toxins, such as microcystins and nodularin, or known metabolites with anti-leukemic activity, such as adenosine and its analogs. A cytotoxicity test on human embryonic kidney (HEK293T) fibroblasts indicated that 21 of the 28 extracts containing anti-acute myeloid leukemia (AML) activity showed selectivity in favor of leukemia cells. Extracts L26-O and L30-O were able to partly overcome the chemotherapy resistance induced by the oncogenic protein Bcl-2, whereas extract L1-O overcame protection from the deletion of the tumor suppressor protein p53. In conclusion, cyanobacteria are a prolific resource for anti-leukemia compounds that have potential for pharmaceutical applications. Based on the variety of cellular responses, we also conclude that the different anti-leukemic compounds in the cyanobacterial extracts target different elements of the death machinery of mammalian cells. PMID:24705501

Cyanobacteria from Terrestrial and Marine Sources Contain Apoptogens Able to Overcome Chemoresistance in Acute Myeloid Leukemia Cells

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Liwei Liu

2014-04-01

Full Text Available In this study, we investigated forty cyanobacterial isolates from biofilms, gastropods, brackish water and symbiotic lichen habitats. Their aqueous and organic extracts were used to screen for apoptosis-inducing activity against acute myeloid leukemia cells. A total of 28 extracts showed cytotoxicity against rat acute myeloid leukemia (IPC-81 cells. The design of the screen made it possible to eliminate known toxins, such as microcystins and nodularin, or known metabolites with anti-leukemic activity, such as adenosine and its analogs. A cytotoxicity test on human embryonic kidney (HEK293T fibroblasts indicated that 21 of the 28 extracts containing anti-acute myeloid leukemia (AML activity showed selectivity in favor of leukemia cells. Extracts L26-O and L30-O were able to partly overcome the chemotherapy resistance induced by the oncogenic protein Bcl-2, whereas extract L1-O overcame protection from the deletion of the tumor suppressor protein p53. In conclusion, cyanobacteria are a prolific resource for anti-leukemia compounds that have potential for pharmaceutical applications. Based on the variety of cellular responses, we also conclude that the different anti-leukemic compounds in the cyanobacterial extracts target different elements of the death machinery of mammalian cells.

Stromal cells expressing hedgehog-interacting protein regulate the proliferation of myeloid neoplasms

International Nuclear Information System (INIS)

Kobune, M; Iyama, S; Kikuchi, S; Horiguchi, H; Sato, T; Murase, K; Kawano, Y; Takada, K; Ono, K; Kamihara, Y; Hayashi, T; Miyanishi, K; Sato, Y; Takimoto, R; Kato, J

2012-01-01

Aberrant reactivation of hedgehog (Hh) signaling has been described in a wide variety of human cancers including cancer stem cells. However, involvement of the Hh-signaling system in the bone marrow (BM) microenvironment during the development of myeloid neoplasms is unknown. In this study, we assessed the expression of Hh-related genes in primary human CD34 + cells, CD34 + blastic cells and BM stromal cells. Both Indian Hh (Ihh) and its signal transducer, smoothened (SMO), were expressed in CD34 + acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS)-derived cells. However, Ihh expression was relatively low in BM stromal cells. Remarkably, expression of the intrinsic Hh-signaling inhibitor, human Hh-interacting protein (HHIP) in AML/MDS-derived stromal cells was markedly lower than in healthy donor-derived stromal cells. Moreover, HHIP expression levels in BM stromal cells highly correlated with their supporting activity for SMO + leukemic cells. Knockdown of HHIP gene in stromal cells increased their supporting activity although control cells marginally supported SMO + leukemic cell proliferation. The demethylating agent, 5-aza-2′-deoxycytidine rescued HHIP expression via demethylation of HHIP gene and reduced the leukemic cell-supporting activity of AML/MDS-derived stromal cells. This indicates that suppression of stromal HHIP could be associated with the proliferation of AML/MDS cells

CD117 expression on blast cells in acute myeloid leukemia

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Goryainova N.V.

2015-09-01

Full Text Available The aim of the present work was to analyze the frequency of CD117 (c-KIT antigen expression on the blast cells in acute myeloid leukemia (AML, evaluation of the presence of the relationship between the expression of the c-KIT and leukemia according to the FAB classification and definition of co-expression of the antigen CD117, antigens CD33 and CD34. The data of 47 patients with AML were diagnosed. M0 AML variant was established in 3 (6% patients, M1 – in 2 (4%, M2 – in 9 (20%, M4 – in 22 (47% and M5 – in 11 (23%. For immunophenotypic stu¬dies monoclonal antibodies (mAb that detect antigens of anti-CD34, anti-CD33 and anti-CD117 (Becton Dickinson, USA were used. The presence of the antigen CD117 was detected in 39 people, accounting for 83% of all surveyed. Antigen c-KIT was present in 48.117.0% cells on average: in all 3 cases – AML M0, in2 cases of AML M1, in 6 cases – AML M2, 20 of 22 cases – AML M4 and in 8 of 11 AML M5 cases. Average levels of CD117 in investigated leukemia cases statistically differed significantly (p=0.0067. Among 39 CD117- positive patients in 25 (53% co-expression of CD117+/CD34+ was revealed. Expression of CD117+/CD34- was observed in 14 cases (30%, CD117-/CD34+ – in 4 cases (8,5%, CD117-/CD34- – in 4 cases (8.5%. CD34 had of 64% of cells of myeloid origin. A high positive cor¬relation between expression of CD117 and CD34 (r=+0,5169 was determined, being statistically significant (p0,0067.

Establishing long-term cultures with self-renewing acute myeloid leukemia stem/progenitor cells

NARCIS (Netherlands)

van Gosliga, Djoke; Schepers, Hein; Rizo, Aleksandra; van der Kolk, Dorina; Vellenga, Edo; Schuringa, Jan Jacob

2007-01-01

Objective. With the emergence of the concept of the leukemia stem cell, assays to study them remain pivotal in understanding (leukemic) stem cell biology. Methods. We have cultured acute myeloid leukemia CD34(+) cells on bone marrow stroma. Long-term expansion was monitored and self-renewal was

Rare myeloid sarcoma/acute myeloid leukemia with adrenal mass after allogeneic mobilization peripheral blood stem cell transplantation

International Nuclear Information System (INIS)

Wang, Ya-Fei; Li, Qian; Xu, Wen-Gui; Xiao, Jian-Yu; Pang, Qing-Song; Yang, Qing; Zhang, Yi-Zuo

2013-01-01

Myeloid sarcoma (MS) is a rare hematological neoplasm that develops either de novo or concurrently with acute myeloid leukemia (AML). This neoplasm can also be an initial manifestation of relapse in a previously treated AML that is in remission. A 44-year-old male patient was diagnosed with testis MS in a local hospital in August 2010. After one month, bone marrow biopsy and aspiration confirmed the diagnosis of AML. Allogeneic mobilization peripheral blood stem cell transplantation was performed, with the sister of the patient as donor, after complete remission (CR) was achieved by chemotherapy. Five months after treatment, an adrenal mass was detected by positron emission tomography-computed tomography (PET-CT). Radiotherapy was performed for the localized mass after a multidisciplinary team (MDT) discussion. The patient is still alive as of May 2013, with no evidence of recurrent MS or leukemia

Radiation Induced Apoptosis of Murine Bone Marrow Cells Is Independent of Early Growth Response 1 (EGR1.

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Karine Z Oben

Full Text Available An understanding of how each individual 5q chromosome critical deleted region (CDR gene contributes to malignant transformation would foster the development of much needed targeted therapies for the treatment of therapy related myeloid neoplasms (t-MNs. Early Growth Response 1 (EGR1 is a key transcriptional regulator of myeloid differentiation located within the 5q chromosome CDR that has been shown to regulate HSC (hematopoietic stem cell quiescence as well as the master regulator of apoptosis-p53. Since resistance to apoptosis is a hallmark of malignant transformation, we investigated the role of EGR1 in apoptosis of bone marrow cells; a cell population from which myeloid malignancies arise. We evaluated radiation induced apoptosis of Egr1+/+ and Egr1-/- bone marrow cells in vitro and in vivo. EGR1 is not required for radiation induced apoptosis of murine bone marrow cells. Neither p53 mRNA (messenger RNA nor protein expression is regulated by EGR1 in these cells. Radiation induced apoptosis of bone marrow cells by double strand DNA breaks induced p53 activation. These results suggest EGR1 dependent signaling mechanisms do not contribute to aberrant apoptosis of malignant cells in myeloid malignancies.

FcγRIIb on myeloid cells rather than on B cells protects from collagen-induced arthritis.

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Yilmaz-Elis, A Seda; Ramirez, Javier Martin; Asmawidjaja, Patrick; van der Kaa, Jos; Mus, Anne-Marie; Brem, Maarten D; Claassens, Jill W C; Breukel, Cor; Brouwers, Conny; Mangsbo, Sara M; Boross, Peter; Lubberts, Erik; Verbeek, J Sjef

2014-06-15

Extensive analysis of a variety of arthritis models in germline KO mice has revealed that all four receptors for the Fc part of IgG (FcγR) play a role in the disease process. However, their precise cell type-specific contribution is still unclear. In this study, we analyzed the specific role of the inhibiting FcγRIIb on B lymphocytes (using CD19Cre mice) and in the myeloid cell compartment (using C/EBPαCre mice) in the development of arthritis induced by immunization with either bovine or chicken collagen type II. Despite their comparable anti-mouse collagen autoantibody titers, full FcγRIIb knockout (KO), but not B cell-specific FcγRIIb KO, mice showed a significantly increased incidence and severity of disease compared with wild-type control mice when immunized with bovine collagen. When immunized with chicken collagen, disease incidence was significantly increased in pan-myeloid and full FcγRIIb KO mice, but not in B cell-specific KO mice, whereas disease severity was only significantly increased in full FcγRIIb KO mice compared with incidence and severity in wild-type control mice. We conclude that, although anti-mouse collagen autoantibodies are a prerequisite for the development of collagen-induced arthritis, their presence is insufficient for disease development. FcγRIIb on myeloid effector cells, as a modulator of the threshold for downstream Ab effector pathways, plays a dominant role in the susceptibility to collagen-induced arthritis, whereas FcγRIIb on B cells, as a regulator of Ab production, has a minor effect on disease susceptibility. Copyright © 2014 by The American Association of Immunologists, Inc.

CD13-positive bone marrow-derived myeloid cells promote angiogenesis, tumor growth, and metastasis.

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Dondossola, Eleonora; Rangel, Roberto; Guzman-Rojas, Liliana; Barbu, Elena M; Hosoya, Hitomi; St John, Lisa S; Molldrem, Jeffrey J; Corti, Angelo; Sidman, Richard L; Arap, Wadih; Pasqualini, Renata

2013-12-17

Angiogenesis is fundamental to tumorigenesis and an attractive target for therapeutic intervention against cancer. We have recently demonstrated that CD13 (aminopeptidase N) expressed by nonmalignant host cells of unspecified types regulate tumor blood vessel development. Here, we compare CD13 wild-type and null bone marrow-transplanted tumor-bearing mice to show that host CD13(+) bone marrow-derived cells promote cancer progression via their effect on angiogenesis. Furthermore, we have identified CD11b(+)CD13(+) myeloid cells as the immune subpopulation directly regulating tumor blood vessel development. Finally, we show that these cells are specifically localized within the tumor microenvironment and produce proangiogenic soluble factors. Thus, CD11b(+)CD13(+) myeloid cells constitute a population of bone marrow-derived cells that promote tumor progression and metastasis and are potential candidates for the development of targeted antiangiogenic drugs.

Low expression of miR-196b enhances the expression of BCR-ABL1 and HOXA9 oncogenes in chronic myeloid leukemogenesis.

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Yue Liu

Full Text Available MicroRNAs (miRNAs can function as tumor suppressors or oncogene promoters during tumor development. In this study, low levels of expression of miR-196b were detected in patients with chronic myeloid leukemia. Bisulfite genomic sequencing PCR and methylation-specific PCR were used to examine the methylation status of the CpG islands in the miR-196b promoter in K562 cells, patients with leukemia and healthy individuals. The CpG islands showed more methylation in patients with chronic myeloid leukemia compared with healthy individuals (P<0.05, which indicated that low expression of miR-196b may be associated with an increase in the methylation of CpG islands. The dual-luciferase reporter assay system demonstrated that BCR-ABL1 and HOXA9 are the target genes of miR-196b, which was consistent with predictions from bioinformatics software analyses. Further examination of cell function indicated that miR-196b acts to reduce BCR-ABL1 and HOXA9 protein levels, decrease cell proliferation rate and retard the cell cycle. A low level of expression of miR-196b can cause up-regulation of BCR-ABL1 and HOXA9 expression, which leads to the development of chronic myeloid leukemia. MiR-196b may represent an effective target for chronic myeloid leukemia therapy.

Social defeat promotes a reactive endothelium in a brain region-dependent manner with increased expression of key adhesion molecules, selectins and chemokines associated with the recruitment of myeloid cells to the brain.

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Sawicki, C M; McKim, D B; Wohleb, E S; Jarrett, B L; Reader, B F; Norden, D M; Godbout, J P; Sheridan, J F

2015-08-27

Repeated social defeat (RSD) in mice causes myeloid cell trafficking to the brain that contributes to the development of prolonged anxiety-like behavior. Myeloid cell recruitment following RSD occurs in regions where neuronal and microglia activation is observed. Thus, we hypothesized that crosstalk between neurons, microglia, and endothelial cells contributes to brain myeloid cell trafficking via chemokine signaling and vascular adhesion molecules. Here we show that social defeat caused an exposure- and brain region-dependent increase in several key adhesion molecules and chemokines involved in the recruitment of myeloid cells. For example, RSD induced distinct patterns of adhesion molecule expression that may explain brain region-dependent myeloid cell trafficking. VCAM-1 and ICAM-1 mRNA expression were increased in an exposure-dependent manner. Furthermore, RSD-induced VCAM-1 and ICAM-1 protein expression were localized to the vasculature of brain regions implicated in fear and anxiety responses, which spatially corresponded to previously reported patterns of myeloid cell trafficking. Next, mRNA expression of additional adhesion molecules (E- and P-selectin, PECAM-1) and chemokines (CXCL1, CXCL2, CXCL12, CCL2) were determined in the brain. Social defeat induced an exposure-dependent increase in mRNA levels of E-selectin, CXCL1, and CXCL2 that increased with additional days of social defeat. While CXCL12 was unaffected by RSD, CCL2 expression was increased by six days of social defeat. Last, comparison between enriched CD11b(+) cells (microglia/macrophages) and enriched GLAST-1(+)/CD11b(-) cells (astrocytes) revealed RSD increased mRNA expression of IL-1β, CCL2, and CXCL2 in microglia/macrophages but not in astrocytes. Collectively, these data indicate that key mediators of leukocyte recruitment were increased in the brain vasculature following RSD in an exposure- and brain region-dependent manner. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights

Myeloid cells in Alzheimer's disease: culprits, victims or innocent bystanders?

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Meyer-Luehmann, Melanie; Prinz, Marco

2015-10-01

Several recent genome-wide association studies (GWAS) in patients with neurodegenerative disorders have shed new light on the brain immune system, suggesting that it plays a pivotal role in disease pathogenesis. Mononuclear phagocytes are blatantly involved in Alzheimer's disease (AD) of the central nervous system (CNS), but the specific functions of resident microglia, perivascular or meningeal macrophages, and circulating myeloid cells have not yet been fully resolved. Next-generation sequencing, high-throughput immune profiling technologies, and novel genetic tools have recently revolutionized the characterization of innate immune responses during AD. These studies advocate selective and non-redundant roles for myeloid subsets, which could be a target for novel disease-modifying therapies in AD. Copyright © 2015 Elsevier Ltd. All rights reserved.

Development of A Chimeric Antigen Receptor Targeting C-Type Lectin-Like Molecule-1 for Human Acute Myeloid Leukemia

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Eduardo Laborda

2017-10-01

Full Text Available The treatment of patients with acute myeloid leukemia (AML with targeted immunotherapy is challenged by the heterogeneity of the disease and a lack of tumor-exclusive antigens. Conventional immunotherapy targets for AML such as CD33 and CD123 have been proposed as targets for chimeric antigen receptor (CAR-engineered T-cells (CAR-T-cells, a therapy that has been highly successful in the treatment of B-cell leukemia and lymphoma. However, CD33 and CD123 are present on hematopoietic stem cells, and targeting with CAR-T-cells has the potential to elicit long-term myelosuppression. C-type lectin-like molecule-1 (CLL1 or CLEC12A is a myeloid lineage antigen that is expressed by malignant cells in more than 90% of AML patients. CLL1 is not expressed by healthy Hematopoietic Stem Cells (HSCs, and is therefore a promising target for CAR-T-cell therapy. Here, we describe the development and optimization of an anti-CLL1 CAR-T-cell with potent activity on both AML cell lines and primary patient-derived AML blasts in vitro while sparing healthy HSCs. Furthermore, in a disseminated mouse xenograft model using the CLL1-positive HL60 cell line, these CAR-T-cells completely eradicated tumor, thus supporting CLL1 as a promising target for CAR-T-cells to treat AML while limiting myelosuppressive toxicity.

The Natural Antiangiogenic Compound AD0157 Induces Caspase-Dependent Apoptosis in Human Myeloid Leukemia Cells

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Melissa García-Caballero

2017-11-01

Full Text Available Evasion of apoptosis is a hallmark of cancer especially relevant in the development and the appearance of leukemia drug resistance mechanisms. The development of new drugs that could trigger apoptosis in aggressive hematological malignancies, such as AML and CML, may be considered a promising antileukemic strategy. AD0157, a natural marine pyrrolidinedione, has already been described as a compound that inhibits angiogenesis by induction of apoptosis in endothelial cells. The crucial role played by defects in the apoptosis pathways in the pathogenesis, progression and response to conventional therapies of several forms of leukemia, moved us to analyze the effect of this compound on the growth and death of leukemia cells. In this work, human myeloid leukemia cells (HL60, U937 and KU812F were treated with AD0157 ranging from 1 to 10 μM and an experimental battery was applied to evaluate its apoptogenic potential. We report here that AD0157 was highly effective to inhibit cell growth by promotion of apoptosis in human myeloid leukemia cells, and provide evidence of its mechanisms of action. The apoptogenic activity of AD0157 on leukemia cells was verified by an increased chromatin condensation and DNA fragmentation, and confirmed by an augmentation in the apoptotic subG1 population, translocation of the membrane phosphatidylserine from the inner face of the plasma membrane to the cell surface and by cleavage of the apoptosis substrates PARP and lamin-A. In addition, AD0157 in the low micromolar range significantly enhanced the activities of the initiator caspases-8 and -9, and the effector caspases-3/-7 in a dose-dependent manner. Results presented here throw light on the apoptogenic mechanism of action of AD0157, mediated through caspase-dependent cascades, with an especially relevant role played by mitochondria. Altogether, these results suggest the therapeutic potential of this compound for the treatment of human myeloid leukemia.

The Thoc1 encoded ribonucleoprotein is required for myeloid progenitor cell homeostasis in the adult mouse.

Science.gov (United States)

Pitzonka, Laura; Ullas, Sumana; Chinnam, Meenalakshmi; Povinelli, Benjamin J; Fisher, Daniel T; Golding, Michelle; Appenheimer, Michelle M; Nemeth, Michael J; Evans, Sharon; Goodrich, David W

2014-01-01

Co-transcriptionally assembled ribonucleoprotein (RNP) complexes are critical for RNA processing and nuclear export. RNPs have been hypothesized to contribute to the regulation of coordinated gene expression, and defects in RNP biogenesis contribute to genome instability and disease. Despite the large number of RNPs and the importance of the molecular processes they mediate, the requirements for individual RNP complexes in mammalian development and tissue homeostasis are not well characterized. THO is an evolutionarily conserved, nuclear RNP complex that physically links nascent transcripts with the nuclear export apparatus. THO is essential for early mouse embryonic development, limiting characterization of the requirements for THO in adult tissues. To address this shortcoming, a mouse strain has been generated allowing inducible deletion of the Thoc1 gene which encodes an essential protein subunit of THO. Bone marrow reconstitution was used to generate mice in which Thoc1 deletion could be induced specifically in the hematopoietic system. We find that granulocyte macrophage progenitors have a cell autonomous requirement for Thoc1 to maintain cell growth and viability. Lymphoid lineages are not detectably affected by Thoc1 loss under the homeostatic conditions tested. Myeloid lineages may be more sensitive to Thoc1 loss due to their relatively high rate of proliferation and turnover.

The Thoc1 encoded ribonucleoprotein is required for myeloid progenitor cell homeostasis in the adult mouse.

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Laura Pitzonka

Full Text Available Co-transcriptionally assembled ribonucleoprotein (RNP complexes are critical for RNA processing and nuclear export. RNPs have been hypothesized to contribute to the regulation of coordinated gene expression, and defects in RNP biogenesis contribute to genome instability and disease. Despite the large number of RNPs and the importance of the molecular processes they mediate, the requirements for individual RNP complexes in mammalian development and tissue homeostasis are not well characterized. THO is an evolutionarily conserved, nuclear RNP complex that physically links nascent transcripts with the nuclear export apparatus. THO is essential for early mouse embryonic development, limiting characterization of the requirements for THO in adult tissues. To address this shortcoming, a mouse strain has been generated allowing inducible deletion of the Thoc1 gene which encodes an essential protein subunit of THO. Bone marrow reconstitution was used to generate mice in which Thoc1 deletion could be induced specifically in the hematopoietic system. We find that granulocyte macrophage progenitors have a cell autonomous requirement for Thoc1 to maintain cell growth and viability. Lymphoid lineages are not detectably affected by Thoc1 loss under the homeostatic conditions tested. Myeloid lineages may be more sensitive to Thoc1 loss due to their relatively high rate of proliferation and turnover.

HLA-DR-, CD33+, CD56+, CD16- myeloid/natural killer cell acute leukemia: a previously unrecognized form of acute leukemia potentially misdiagnosed as French-American-British acute myeloid leukemia-M3.

Science.gov (United States)

Scott, A A; Head, D R; Kopecky, K J; Appelbaum, F R; Theil, K S; Grever, M R; Chen, I M; Whittaker, M H; Griffith, B B; Licht, J D

1994-07-01

We have identified and characterized a previously unrecognized form of acute leukemia that shares features of both myeloid and natural killer (NK) cells. From a consecutive series of 350 cases of adult de novo acute myeloid leukemia (AML), we identified 20 cases (6%) with a unique immunophenotype: CD33+, CD56+, CD11a+, CD13lo, CD15lo, CD34+/-, HLA-DR-, CD16-. Multicolor flow cytometric assays confirmed the coexpression of myeloid (CD33, CD13, CD15) and NK cell-associated (CD56) antigens in each case, whereas reverse transcription polymerase chain reaction (RT-PCR) assays confirmed the identity of CD56 (neural cell adhesion molecule) in leukemic blasts. Although two cases expressed CD4, no case expressed CD2, CD3, or CD8 and no case showed clonal rearrangement of genes encoding the T-cell receptor (TCR beta, gamma, delta). Leukemic blasts in the majority of cases shared unique morphologic features (deeply invaginated nuclear membranes, scant cytoplasm with fine azurophilic granularity, and finely granular Sudan black B and myeloperoxidase cytochemical reactivity) that were remarkably similar to those of acute promyelocytic leukemia (APL); particularly the microgranular variant (FAB AML-M3v). However, all 20 cases lacked the t(15;17) and 17 cases tested lacked the promyelocytic/retinoic acid receptor alpha (RAR alpha) fusion transcript in RT-PCR assays; 12 cases had 46,XX or 46,XY karyotypes, whereas 2 cases had abnormalities of chromosome 17q: 1 with del(17)(q25) and the other with t(11;17)(q23;q21) and the promyelocytic leukemia zinc finger/RAR alpha fusion transcript. All cases tested (6/20), including the case with t(11;17), failed to differentiate in vitro in response to all-trans retinoic acid (ATRA), suggesting that these cases may account for some APLs that have not shown a clinical response to ATRA. Four of 6 cases tested showed functional NK cell-mediated cytotoxicity, suggesting a relationship between these unique CD33+, CD56+, CD16- acute leukemias and

Activity of Bruton's tyrosine-kinase inhibitor ibrutinib in patients with CD117-positive acute myeloid leukaemia: a mechanistic study using patient-derived blast cells.

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Rushworth, Stuart A; Pillinger, Genevra; Abdul-Aziz, Amina; Piddock, Rachel; Shafat, Manar S; Murray, Megan Y; Zaitseva, Lyubov; Lawes, Matthew J; MacEwan, David J; Bowles, Kristian M

2015-05-01

Roughly 80% of patients with acute myeloid leukaemia have high activity of Bruton's tyrosine-kinase (BTK) in their blast cells compared with normal haemopoietic cells, rendering the cells sensitive to the oral BTK inhibitor ibrutinib in vitro. We aimed to develop the biological understanding of the BTK pathway in acute myeloid leukaemia to identify clinically relevant diagnostic information that might define a subset of patients that should respond to ibrutinib treatment. We obtained acute myeloid leukaemia blast cells from unselected patients attending our UK hospital between Feb 19, 2010, and Jan 20, 2014. We isolated primary acute myeloid leukaemia blast cells from heparinised blood and human peripheral blood mononuclear cells to establish the activity of BTK in response to CD117 activation. Furthermore, we investigated the effects of ibrutinib on CD117-induced BTK activation, downstream signalling, adhesion to primary bone-marrow mesenchymal stromal cells, and proliferation of primary acute myeloid leukaemia blast cells. We used the Mann-Whitney U test to compare results between groups. We obtained acute myeloid leukaemia blast cells from 29 patients. Ibrutinib significantly inhibited CD117-mediated proliferation of primary acute myeloid leukaemia blast cells (p=0·028). CD117 activation increased BTK activity by inducing phosphorylated BTK in patients with CD117-positive acute myeloid leukaemia. Furthermore, ibrutinib inhibited CD117-induced activity of BTK and downstream kinases at a concentration of 100 nM or more. CD117-mediated adhesion of CD117-expressing blast cells to bone-marrow stromal cells was significantly inhibited by Ibrutinib at 500 nM (p=0·028) INTERPRETATION: As first-in-man clinical trials of ibrutinib in patients with acute myeloid leukaemia commence, the data suggest not all patients will respond. Our findings show that BTK has specific pro-tumoural biological actions downstream of surface CD117 activation, which are inhibited by ibrutinib

The rate of spontaneous mutations in human myeloid cells

International Nuclear Information System (INIS)

Araten, David J.; Krejci, Ondrej; DiTata, Kimberly; Wunderlich, Mark; Sanders, Katie J.; Zamechek, Leah; Mulloy, James C.

2013-01-01

Highlights: • We provide the first measurement of the mutation rate (μ) in human myeloid cells. • μ is measured to be 3.6–23 × 10 −7 per cell division. • The AML-ETO and MLL-AF9 fusions do not seem to increase μ. • Cooperating mutations in NRAS, FLT3 and p53 not seem to increase μ. • Hypermutability may be required to explain leukemogenesis. - Abstract: The mutation rate (μ) is likely to be a key parameter in leukemogenesis, but historically, it has been difficult to measure in humans. The PIG-A gene has some advantages for the detection of spontaneous mutations because it is X-linked, and therefore only one mutation is required to disrupt its function. Furthermore, the PIG-A-null phenotype is readily detected by flow cytometry. Using PIG-A, we have now provided the first in vitro measurement of μ in myeloid cells, using cultures of CD34+ cells that are transduced with either the AML-ETO or the MLL-AF9 fusion genes and expanded with cytokines. For the AML-ETO cultures, the median μ value was ∼9.4 × 10 −7 (range ∼3.6–23 × 10 −7 ) per cell division. In contrast, few spontaneous mutations were observed in the MLL-AF9 cultures. Knockdown of p53 or introduction of mutant NRAS or FLT3 alleles did not have much of an effect on μ. Based on these data, we provide a model to predict whether hypermutability must occur in the process of leukemogenesis

Dasatinib accelerates valproic acid-induced acute myeloid leukemia cell death by regulation of differentiation capacity.

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Sook-Kyoung Heo

Full Text Available Dasatinib is a compound developed for chronic myeloid leukemia as a multi-targeted kinase inhibitor against wild-type BCR-ABL and SRC family kinases. Valproic acid (VPA is an anti-epileptic drug that also acts as a class I histone deacetylase inhibitor. The aim of this research was to determine the anti-leukemic effects of dasatinib and VPA in combination and to identify their mechanism of action in acute myeloid leukemia (AML cells. Dasatinib was found to exert potent synergistic inhibitory effects on VPA-treated AML cells in association with G1 phase cell cycle arrest and apoptosis induction involving the cleavage of poly (ADP-ribose polymerase and caspase-3, -7 and -9. Dasatinib/VPA-induced cell death thus occurred via caspase-dependent apoptosis. Moreover, MEK/ERK and p38 MAPK inhibitors efficiently inhibited dasatinib/VPA-induced apoptosis. The combined effect of dasatinib and VPA on the differentiation capacity of AML cells was more powerful than the effect of each drug alone, being sufficiently strong to promote AML cell death through G1 cell cycle arrest and caspase-dependent apoptosis. MEK/ERK and p38 MAPK were found to control dasatinib/VPA-induced apoptosis as upstream regulators, and co-treatment with dasatinib and VPA to contribute to AML cell death through the regulation of differentiation capacity. Taken together, these results indicate that combined dasatinib and VPA treatment has a potential role in anti-leukemic therapy.

Osteoclasts in multiple myeloma are derived from Gr-1+CD11b+myeloid-derived suppressor cells.

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Junling Zhuang

Full Text Available Osteoclasts play a key role in the development of cancer-associated osteolytic lesions. The number and activity of osteoclasts are often enhanced by tumors. However, the origin of osteoclasts is unknown. Myeloid-derived suppressor cells (MDSCs are one of the pre-metastatic niche components that are induced to expand by tumor cells. Here we show that the MDSCs can differentiate into mature and functional osteoclasts in vitro and in vivo. Inoculation of 5TGM1-GFP myeloma cells into C57BL6/KaLwRij mice led to a significant expansion of MDSCs in blood, spleen, and bone marrow over time. When grown in osteoclastogenic media in vitro, MDSCs from tumor-challenged mice displayed 14 times greater potential to differentiate into mature and functional osteoclasts than those from non-tumor controls. Importantly, MDSCs from tumor-challenged LacZ transgenic mice differentiated into LacZ+osteoclasts in vivo. Furthermore, a significant increase in tumor burden and bone loss accompanied by increased number of osteoclasts was observed in mice co-inoculated with tumor-challenged MDSCs and 5TGM1 cells compared to the control animals received 5TGM1 cells alone. Finally, treatment of MDSCs from myeloma-challenged mice with Zoledronic acid (ZA, a potent inhibitor of bone resorption, inhibited the number of osteoclasts formed in MDSC cultures and the expansion of MDSCs and bone lesions in mice. Collectively, these data provide in vitro and in vivo evidence that tumor-induced MDSCs exacerbate cancer-associated bone destruction by directly serving as osteoclast precursors.

Acute myeloid leukemia stem cell markers in prognosis and targeted therapy: potential impact of BMI-1, TIM-3 and CLL-1.

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Darwish, Noureldien H E; Sudha, Thangirala; Godugu, Kavitha; Elbaz, Osama; Abdelghaffar, Hasan A; Hassan, Emad E A; Mousa, Shaker A

2016-09-06

Acute myeloid leukemia (AML) patients show high relapse rates and some develop conventional chemotherapy resistance. Leukemia Stem Cells (LSCs) are the main player for AML relapses and drug resistance. LSCs might rely on the B-cell-specific Moloney murine leukemia virus integration site-1 (BMI-1) in promoting cellular proliferation and survival. Growth of LSCs in microenvironments that are deprived of nutrients leads to up-regulation of the signaling pathways during the progression of the disease, which may illustrate the sensitivity of LSCs to inhibitors of those signaling pathways as compared to normal cells. We analyzed the expression of LSC markers (CD34, CLL-1, TIM-3 and BMI-1) using quantitative RT-PCR in bone marrow samples of 40 AML patients of different FAB types (M1, M2, M3, M4, M5, and M7). We also studied the expression of these markers in 2 AML cell lines (Kasumi-1 and KG-1a) using flow cytometry and quantitative RT-PCR. The overexpression of TIM-3, CLL-1, and BMI-1 was markedly correlated with poor prognosis in these patients. Our in vitro findings demonstrate that targeting BMI-1, which markedly increased in the leukemic cells, was associated with marked decrease in leukemic burden. This study also presents results for blocking LSCs' surface markers CD44, CLL-1, and TIM-3. These markers may play an important role in elimination of AML. Our study indicates a correlation between the expression of markers TIM-3, CLL-1, and especially of BMI-1 and the aggressiveness of AML and thus the potential impact of prognosis and therapies that target LSCs on improving the cure rates.

Recurrent SETBP1 mutations in atypical chronic myeloid leukemia

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Piazza, Rocco; Valletta, Simona; Winkelmann, Nils; Redaelli, Sara; Spinelli, Roberta; Pirola, Alessandra; Antolini, Laura; Mologni, Luca; Donadoni, Carla; Papaemmanuil, Elli; Schnittger, Susanne; Kim, Dong-Wook; Boultwood, Jacqueline; Rossi, Fabio; Gaipa, Giuseppe; De Martini, Greta P; di Celle, Paola Francia; Jang, Hyun Gyung; Fantin, Valeria; Bignell, Graham R; Magistroni, Vera; Haferlach, Torsten; Pogliani, Enrico Maria; Campbell, Peter J; Chase, Andrew J; Tapper, William J; Cross, Nicholas C P; Gambacorti-Passerini, Carlo

2013-01-01

Atypical chronic myeloid leukemia (aCML) shares clinical and laboratory features with CML, but it lacks the BCR-ABL1 fusion. We performed exome sequencing of eight aCMLs and identified somatic alterations of SETBP1 (encoding a p.Gly870Ser alteration) in two cases. Targeted resequencing of 70 aCMLs, 574 diverse hematological malignancies and 344 cancer cell lines identified SETBP1 mutations in 24 cases, including 17 of 70 aCMLs (24.3%; 95% confidence interval (CI) = 16–35%). Most mutations (92%) were located between codons 858 and 871 and were identical to changes seen in individuals with Schinzel-Giedion syndrome. Individuals with mutations had higher white blood cell counts (P = 0.008) and worse prognosis (P = 0.01). The p.Gly870Ser alteration abrogated a site for ubiquitination, and cells exogenously expressing this mutant exhibited higher amounts of SETBP1 and SET protein, lower PP2A activity and higher proliferation rates relative to those expressing the wild-type protein. In summary, mutated SETBP1 represents a newly discovered oncogene present in aCML and closely related diseases. PMID:23222956

A PU.1 suppressive target gene, metallothionein 1G, inhibits retinoic acid-induced NB4 cell differentiation.

Directory of Open Access Journals (Sweden)

Naomi Hirako

Full Text Available We recently revealed that myeloid master regulator SPI1/PU.1 directly represses metallothionein (MT 1G through its epigenetic activity of PU.1, but the functions of MT1G in myeloid differentiation remain unknown. To clarify this, we established MT1G-overexpressing acute promyelocytic leukemia NB4 (NB4MTOE cells, and investigated whether MT1G functionally contributes to all-trans retinoic acid (ATRA-induced NB4 cell differentiation. Real-time PCR analyses demonstrated that the inductions of CD11b and CD11c and reductions in myeloperoxidase and c-myc by ATRA were significantly attenuated in NB4MTOE cells. Morphological examination revealed that the percentages of differentiated cells induced by ATRA were reduced in NB4MTOE cells. Since G1 arrest is a hallmark of ATRA-induced NB4 cell differentiation, we observed a decrease in G1 accumulation, as well as decreases in p21WAF1/CIP1 and cyclin D1 inductions, by ATRA in NB4MTOE cells. Nitroblue tetrazolium (NBT reduction assays revealed that the proportions of NBT-positive cells were decreased in NB4MTOE cells in the presence of ATRA. Microarray analyses showed that the changes in expression of several myeloid differentiation-related genes (GATA2, azurocidin 1, pyrroline-5-carboxylate reductase 1, matrix metallopeptidase -8, S100 calcium-binding protein A12, neutrophil cytosolic factor 2 and oncostatin M induced by ATRA were disturbed in NB4MTOE cells. Collectively, overexpression of MT1G inhibits the proper differentiation of myeloid cells.

Inflammation- and tumor-induced anorexia and weight loss require MyD88 in hematopoietic/myeloid cells but not in brain endothelial or neural cells.

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Ruud, Johan; Wilhelms, Daniel Björk; Nilsson, Anna; Eskilsson, Anna; Tang, Yan-Juan; Ströhle, Peter; Caesar, Robert; Schwaninger, Markus; Wunderlich, Thomas; Bäckhed, Fredrik; Engblom, David; Blomqvist, Anders

2013-05-01

Loss of appetite is a hallmark of inflammatory diseases. The underlying mechanisms remain undefined, but it is known that myeloid differentiation primary response gene 88 (MyD88), an adaptor protein critical for Toll-like and IL-1 receptor family signaling, is involved. Here we addressed the question of determining in which cells the MyD88 signaling that results in anorexia development occurs by using chimeric mice and animals with cell-specific deletions. We found that MyD88-knockout mice, which are resistant to bacterial lipopolysaccharide (LPS)-induced anorexia, displayed anorexia when transplanted with wild-type bone marrow cells. Furthermore, mice with a targeted deletion of MyD88 in hematopoietic or myeloid cells were largely protected against LPS-induced anorexia and displayed attenuated weight loss, whereas mice with MyD88 deletion in hepatocytes or in neural cells or the cerebrovascular endothelium developed anorexia and weight loss of similar magnitude as wild-type mice. Furthermore, in a model for cancer-induced anorexia-cachexia, deletion of MyD88 in hematopoietic cells attenuated the anorexia and protected against body weight loss. These findings demonstrate that MyD88-dependent signaling within the brain is not required for eliciting inflammation-induced anorexia. Instead, we identify MyD88 signaling in hematopoietic/myeloid cells as a critical component for acute inflammatory-driven anorexia, as well as for chronic anorexia and weight loss associated with malignant disease.

An evidence for adhesion-mediated acquisition of acute myeloid leukemic stem cell-like immaturities

International Nuclear Information System (INIS)

Funayama, Keiji; Shimane, Miyuki; Nomura, Hitoshi; Asano, Shigetaka

2010-01-01

For long-term survival in vitro and in vivo of acute myeloid leukemia cells, their adhesion to bone marrow stromal cells is indispensable. However, it is still unknown if these events are uniquely induced by the leukemic stem cells. Here we show that TF-1 human leukemia cells, once they have formed a cobblestone area by adhering to mouse bone marrow-derived MS-5 cells, can acquire some leukemic stem cell like properties in association with a change in the CD44 isoform-expression pattern and with an increase in a set of related microRNAs. These findings strongly suggest that at least some leukemia cells can acquire leukemic stem cell like properties in an adhesion-mediated stochastic fashion.

An evidence for adhesion-mediated acquisition of acute myeloid leukemic stem cell-like immaturities

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Funayama, Keiji; Shimane, Miyuki; Nomura, Hitoshi [Department of Integrative Bioscience and Biomedical Engineering, Waseda University, 4-3-1 Ohkubo, Shinjuku-ku, Tokyo 169-8555 (Japan); Asano, Shigetaka, E-mail: asgtkmd@waseda.jp [Department of Integrative Bioscience and Biomedical Engineering, Waseda University, 4-3-1 Ohkubo, Shinjuku-ku, Tokyo 169-8555 (Japan)

2010-02-12

For long-term survival in vitro and in vivo of acute myeloid leukemia cells, their adhesion to bone marrow stromal cells is indispensable. However, it is still unknown if these events are uniquely induced by the leukemic stem cells. Here we show that TF-1 human leukemia cells, once they have formed a cobblestone area by adhering to mouse bone marrow-derived MS-5 cells, can acquire some leukemic stem cell like properties in association with a change in the CD44 isoform-expression pattern and with an increase in a set of related microRNAs. These findings strongly suggest that at least some leukemia cells can acquire leukemic stem cell like properties in an adhesion-mediated stochastic fashion.

In vitro evaluation of triazenes: DNA cleavage, antibacterial activity and cytotoxicity against acute myeloid leukemia cells

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Domingues, Vanessa O.; Hoerner, Rosmari; Reetz, Luiz G.B.; Kuhn, Fabio, E-mail: rosmari.ufsm@gmail.co [Universidade Federal de Santa Maria (UFSM), RS (Brazil). Dept. de Analises Clinicas e Toxicologicas; Coser, Virginia M.; Rodrigues, Jacqueline N.; Bauchspiess, Rita; Pereira, Waldir V. [Hospital Universitario de Santa Maria, RS (Brazil). Dept. de Hematologia-Oncologia; Paraginski, Gustavo L.; Locatelli, Aline; Fank, Juliana de O.; Giglio, Vinicius F.; Hoerner, Manfredo, E-mail: hoerner.manfredo@gmail.co [Universidade Federal de Santa Maria (UFSM), RS (Brazil). Dept. de Quimica

2010-07-01

The asymmetric diazoamines 1-(2-chlorophenyl)-3-(4-carboxyphenyl)triazene (1), 1-(2-fluorophenyl)-3-(4-carboxyphenyl)triazene (2) and 1-(2-fluorophenyl)-3-(4-amidophenyl) triazene (3) were evaluated for their ability to cleave pUC18 and pBSKII plasmid DNA, antibacterial activity and in vitro cytotoxicity against acute myeloid leukemia cells and normal leukocytes using the bioassay of reduction of 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide (MTT). The triazenes showed ability to cleave the two types of plasmid DNA: triazene 1 at pH 8.0 and 50 deg C; triazene 2 at pH 6.5 and 37 and 50 deg C; triazene 3 at pH 6.5 and 37 deg C. The compounds presented cytotoxic activity against myeloid leukemia cells. Compound 1 showed high activity against B. cereus (MIC = 32 {mu}g mL{sup -1}). The observation of intermolecular hydrogen bonding in the solid state of compound 3, based on the structural analysis by X-ray crystallography, as well as the results of IR and UV-Vis spectroscopic analyses of compounds 1, 2 and 3 are discussed in the present work. (author)

Pam2 lipopeptides systemically increase myeloid-derived suppressor cells through TLR2 signaling

Energy Technology Data Exchange (ETDEWEB)

Maruyama, Akira; Shime, Hiroaki, E-mail: shime@med.hokudai.ac.jp; Takeda, Yohei; Azuma, Masahiro; Matsumoto, Misako; Seya, Tsukasa, E-mail: seya-tu@pop.med.hokudai.ac.jp

2015-02-13

Myeloid-derived suppressor cells (MDSCs) are immature myeloid cells that exhibit potent immunosuppressive activity. They are increased in tumor-bearing hosts and contribute to tumor development. Toll-like receptors (TLRs) on MDSCs may modulate the tumor-supporting properties of MDSCs through pattern-recognition. Pam2 lipopeptides represented by Pam2CSK4 serve as a TLR2 agonist to exert anti-tumor function by dendritic cell (DC)-priming that leads to NK cell activation and cytotoxic T cell proliferation. On the other hand, TLR2 enhances tumor cell progression/invasion by activating tumor-infiltrating macrophages. How MDSCs respond to TLR2 agonists has not yet been determined. In this study, we found intravenous administration of Pam2CSK4 systemically up-regulated the frequency of MDSCs in EG7 tumor-bearing mice. The frequency of tumor-infiltrating MDSCs was accordingly increased in response to Pam2CSK4. MDSCs were not increased by Pam2CSK4 stimuli in TLR2 knockout (KO) mice. Adoptive transfer experiments using CFSE-labeled MDSCs revealed that the TLR2-positive MDSCs survived long in tumor-bearing mice in response to Pam2CSK4 treatment. Since the increased MDSC population sustained immune-suppressive properties, our study suggests that Pam2CSK4-triggered TLR2 activation enhances the MDSC potential and suppress antitumor immune response in tumor microenvironment. - Highlights: • Pam2CSK4 administration induces systemic accumulation of CD11b{sup +}Gr1{sup +} MDSCs. • TLR2 is essential for Pam2CSK4-induced accumulation of CD11b{sup +}Gr1{sup +} MDSCs. • Pam2CSK4 supports survival of CD11b{sup +}Gr1{sup +} MDSCs in vivo.

Myeloid clusters are associated with a pro-metastatic environment and poor prognosis in smoking-related early stage non-small cell lung cancer.

Directory of Open Access Journals (Sweden)

Wang Zhang

Full Text Available This study aimed to understand the role of myeloid cell clusters in uninvolved regional lymph nodes from early stage non-small cell lung cancer patients.Uninvolved regional lymph node sections from 67 patients with stage I-III resected non-small cell lung cancer were immunostained to detect myeloid clusters, STAT3 activity and occult metastasis. Anthracosis intensity, myeloid cluster infiltration associated with anthracosis and pSTAT3 level were scored and correlated with patient survival. Multivariate Cox regression analysis was performed with prognostic variables. Human macrophages were used for in vitro nicotine treatment.CD68+ myeloid clusters associated with anthracosis and with an immunosuppressive and metastasis-promoting phenotype and elevated overall STAT3 activity were observed in uninvolved lymph nodes. In patients with a smoking history, myeloid cluster score significantly correlated with anthracosis intensity and pSTAT3 level (P<0.01. Nicotine activated STAT3 in macrophages in long-term culture. CD68+ myeloid clusters correlated and colocalized with occult metastasis. Myeloid cluster score was an independent prognostic factor (P = 0.049 and was associated with survival by Kaplan-Maier estimate in patients with a history of smoking (P = 0.055. The combination of myeloid cluster score with either lymph node stage or pSTAT3 level defined two populations with a significant difference in survival (P = 0.024 and P = 0.004, respectively.Myeloid clusters facilitate a pro-metastatic microenvironment in uninvolved regional lymph nodes and associate with occult metastasis in early stage non-small cell lung cancer. Myeloid cluster score is an independent prognostic factor for survival in patients with a history of smoking, and may present a novel method to inform therapy choices in the adjuvant setting. Further validation studies are warranted.

ATM facilitates mouse gammaherpesvirus reactivation from myeloid cells during chronic infection.

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Kulinski, Joseph M; Darrah, Eric J; Broniowska, Katarzyna A; Mboko, Wadzanai P; Mounce, Bryan C; Malherbe, Laurent P; Corbett, John A; Gauld, Stephen B; Tarakanova, Vera L

2015-09-01

Gammaherpesviruses are cancer-associated pathogens that establish life-long infection in most adults. Insufficiency of Ataxia-Telangiectasia mutated (ATM) kinase leads to a poor control of chronic gammaherpesvirus infection via an unknown mechanism that likely involves a suboptimal antiviral response. In contrast to the phenotype in the intact host, ATM facilitates gammaherpesvirus reactivation and replication in vitro. We hypothesized that ATM mediates both pro- and antiviral activities to regulate chronic gammaherpesvirus infection in an immunocompetent host. To test the proposed proviral activity of ATM in vivo, we generated mice with ATM deficiency limited to myeloid cells. Myeloid-specific ATM deficiency attenuated gammaherpesvirus infection during the establishment of viral latency. The results of our study uncover a proviral role of ATM in the context of gammaherpesvirus infection in vivo and support a model where ATM combines pro- and antiviral functions to facilitate both gammaherpesvirus-specific T cell immune response and viral reactivation in vivo. Copyright © 2015 Elsevier Inc. All rights reserved.

History of myeloid derived suppressor cells (MDSCs) in the macro- and micro-environment of tumour-bearing hosts

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Talmadge, James E.; Gabrilovich, Dmitry I.

2015-01-01

Tumour-induced granulocytic hyperplasia is associated with tumour vasculogenesis and escape from immunity via T-cell suppression. Initially, these myeloid cells were identified as granulocytes or monocytes; however, recent studies revealed that this hyperplasia was associated with populations of multi-potent progenitor cells identified as myeloid-derived suppressor cells (MDSCs). The discovery and study of MDSCs have provided a wealth of information regarding tumour pathobiology, extended our understanding of neoplastic progression, and modified our approaches to immune adjuvant therapy. In this perspective, we discuss the history of MDSCs, their influence on tumour progression and metastasis, and the crosstalk between tumour cells, MDSCs, and the host macroenvironment. PMID:24060865

Myeloid Heme Oxygenase-1 Regulates the Acute Inflammatory Response to Zymosan in the Mouse Air Pouch

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Rita Brines

2018-01-01

Full Text Available Heme oxygenase-1 (HO-1 is induced by many stimuli to modulate the activation and function of different cell types during innate immune responses. Although HO-1 has shown anti-inflammatory effects in different systems, there are few data on the contribution of myeloid HO-1 and its role in inflammatory processes is not well understood. To address this point, we have used HO-1M-KO mice with myeloid-restricted deletion of HO-1 to specifically investigate its influence on the acute inflammatory response to zymosan in vivo. In the mouse air pouch model, we have shown an exacerbated inflammation in HO-1M-KO mice with increased neutrophil infiltration accompanied by high levels of inflammatory mediators such as interleukin-1β, tumor necrosis factor-α, and prostaglandin E2. The expression of the degradative enzyme matrix metalloproteinase-3 (MMP-3 was also enhanced. In addition, we observed higher levels of serum MMP-3 in HO-1M-KO mice compared with control mice, suggesting the presence of systemic inflammation. Altogether, these findings demonstrate that myeloid HO-1 plays an anti-inflammatory role in the acute response to zymosan in vivo and suggest the interest of this target to regulate inflammatory processes.

Multiplex CRISPR/Cas9-Based Genome Editing in Human Hematopoietic Stem Cells Models Clonal Hematopoiesis and Myeloid Neoplasia.

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Tothova, Zuzana; Krill-Burger, John M; Popova, Katerina D; Landers, Catherine C; Sievers, Quinlan L; Yudovich, David; Belizaire, Roger; Aster, Jon C; Morgan, Elizabeth A; Tsherniak, Aviad; Ebert, Benjamin L

2017-10-05

Hematologic malignancies are driven by combinations of genetic lesions that have been difficult to model in human cells. We used CRISPR/Cas9 genome engineering of primary adult and umbilical cord blood CD34 + human hematopoietic stem and progenitor cells (HSPCs), the cells of origin for myeloid pre-malignant and malignant diseases, followed by transplantation into immunodeficient mice to generate genetic models of clonal hematopoiesis and neoplasia. Human hematopoietic cells bearing mutations in combinations of genes, including cohesin complex genes, observed in myeloid malignancies generated immunophenotypically defined neoplastic clones capable of long-term, multi-lineage reconstitution and serial transplantation. Employing these models to investigate therapeutic efficacy, we found that TET2 and cohesin-mutated hematopoietic cells were sensitive to azacitidine treatment. These findings demonstrate the potential for generating genetically defined models of human myeloid diseases, and they are suitable for examining the biological consequences of somatic mutations and the testing of therapeutic agents. Copyright © 2017 Elsevier Inc. All rights reserved.

Coexistence of chronic myeloid leukemia and diffuse large B-cell lymphoma with antecedent chronic lymphocytic leukemia: a case report and review of the literature.

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Abuelgasim, Khadega A; Rehan, Hinna; Alsubaie, Maha; Al Atwi, Nasser; Al Balwi, Mohammed; Alshieban, Saeed; Almughairi, Areej

2018-03-11

Chronic lymphocytic leukemia and chronic myeloid leukemia are the most common types of adult leukemia. However, it is rare for the same patient to suffer from both. Richter's transformation to diffuse large B-cell lymphoma is frequently observed in chronic lymphocytic leukemia. Purine analog therapy and the presence of trisomy 12, and CCND1 gene rearrangement have been linked to increased risk of Richter's transformation. The coexistence of chronic myeloid leukemia and diffuse large B-cell lymphoma in the same patient is extremely rare, with only nine reported cases. Here, we describe the first reported case of concurrent chronic myeloid leukemia and diffuse large B-cell lymphoma in a background of chronic lymphocytic leukemia. A 60-year-old Saudi man known to have diabetes, hypertension, and chronic active hepatitis B was diagnosed as having Rai stage II chronic lymphocytic leukemia, with trisomy 12 and rearrangement of the CCND1 gene in December 2012. He required no therapy until January 2016 when he developed significant anemia, thrombocytopenia, and constitutional symptoms. He received six cycles of fludarabine, cyclophosphamide, and rituximab, after which he achieved complete remission. One month later, he presented with progressive leukocytosis (mostly neutrophilia) and splenomegaly. Fluorescence in situ hybridization from bone marrow aspirate was positive for translocation (9;22) and reverse transcription polymerase chain reaction detected BCR-ABL fusion gene consistent with chronic myeloid leukemia. He had no morphologic or immunophenotypic evidence of chronic lymphocytic leukemia at the time. Imatinib, a first-line tyrosine kinase inhibitor, was started. Eight months later, a screening imaging revealed new liver lesions, which were confirmed to be diffuse large B-cell lymphoma. In chronic lymphocytic leukemia, progressive leukocytosis and splenomegaly caused by emerging chronic myeloid leukemia can be easily overlooked. It is unlikely that chronic myeloid

Activated factor X signaling via protease-activated receptor 2 suppresses pro-inflammatory cytokine production from LPS-stimulated myeloid cells.

LENUS (Irish Health Repository)

Gleeson, Eimear M

2013-07-19

Vitamin K-dependent proteases generated in response to vascular injury and infection enable fibrin clot formation, but also trigger distinct immuno-regulatory signaling pathways on myeloid cells. Factor Xa, a protease crucial for blood coagulation, also induces protease-activated receptor-dependent cell signaling. Factor Xa can bind both monocytes and macrophages, but whether factor Xa-dependent signaling stimulates or suppresses myeloid cell cytokine production in response to Toll-like receptor activation is not known. In this study, exposure to factor Xa significantly impaired pro-inflammatory cytokine production from lipopolysaccharide-treated peripheral blood mononuclear cells, THP-1 monocytic cells and murine macrophages. Furthermore, factor Xa inhibited nuclear factor-kappa B activation in THP-1 reporter cells, requiring phosphatidylinositide 3-kinase activity for its anti-inflammatory effect. Active-site blockade, γ-carboxyglutamic acid domain truncation and a peptide mimic of the factor Xa inter-epidermal growth factor-like region prevented factor Xa inhibition of lipopolysaccharide-induced tumour necrosis factor-α release. In addition, factor Xa anti-inflammatory activity was markedly attenuated by the presence of an antagonist of protease-activated receptor 2, but not protease-activated receptor 1. The key role of protease-activated receptor 2 in eliciting factor Xa-dependent anti-inflammatory signaling on macrophages was further underscored by the inability of factor Xa to mediate inhibition of tumour necrosis factor-α and interleukin-6 release from murine bone marrow-derived protease-activated receptor 2-deficient macrophages. We also show for the first time that, in addition to protease-activated receptor 2, factor Xa requires a receptor-associated protein-sensitive low-density lipoprotein receptor to inhibit lipopolysaccharide-induced cytokine production. Collectively, this study supports a novel function for factor Xa as an endogenous, receptor

Adiponectin deficiency suppresses lymphoma growth in mice by modulating NK cells, CD8 T cells, and myeloid-derived suppressor cells.

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Han, Sora; Jeong, Ae Lee; Lee, Sunyi; Park, Jeong Su; Kim, Kwang Dong; Choi, Inpyo; Yoon, Suk Ran; Lee, Myung Sok; Lim, Jong-Seok; Han, Seung Hyun; Yoon, Do Young; Yang, Young

2013-05-01

Previously, we found that adiponectin (APN) suppresses IL-2-induced NK cell activation by downregulating the expression of the IFN-γ-inducible TNF-related apoptosis-inducing ligand and Fas ligand. Although the antitumor function of APN has been reported in several types of solid tumors, with few controversial results, no lymphoma studies have been conducted. In this study, we assessed the role of APN in immune cell function, including NK cells, CTLs, and myeloid-derived suppressor cells, in EL4 and B16F10 tumor-bearing APN knockout (KO) mice. We observed attenuated EL4 growth in the APNKO mice. Increased numbers of splenic NK cells and splenic CTLs were identified under naive conditions and EL4-challenged conditions, respectively. In APNKO mice, splenic NK cells showed enhanced cytotoxicity with and without IL-2 stimulation. Additionally, there were decreased levels of myeloid-derived suppressor cell accumulation in the EL4-bearing APNKO mice. Enforced MHC class I expression on B16F10 cells led to attenuated growth of these tumors in APNKO mice. Thus, our results suggest that EL4 regression in APNKO mice is not only due to an enhanced antitumor immune response but also to a high level of MHC class I expression.

Diagnostic confusion resulting from CD56 expression by cutaneous myeloid sarcoma

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Sheeja T. Pullarkat

2009-12-01

Full Text Available Myeloid sarcomas are tumor masses composed of aggregates of malignant myeloid precursors in extramedullary sites including the skin. We report a case of myeloid sarcoma in a patient who presented with an ear lobe mass and facial nerve paralysis. Expression of CD56 by the malignant cells led to an initial misdiagnosis as Merkel cell tumor. Comprehensive pathological evaluation confirmed the diagnosis of myeloid sarcoma with aberrant expression of CD56 and carrying the translocation t(8;21 (q22;q22. Aberrant antigen expression by cutaneous myeloid sarcomas can cause diagnostic confusion with other cutaneous neoplasms. This is especially relevant when myeloid sarcoma is the sole manifestation of acute myeloid leukemia.

PI3-kinase γ promotes Rap1a-mediated activation of myeloid cell integrin α4β1, leading to tumor inflammation and growth.

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Michael C Schmid

Full Text Available Tumor inflammation, the recruitment of myeloid lineage cells into the tumor microenvironment, promotes angiogenesis, immunosuppression and metastasis. CD11b+Gr1lo monocytic lineage cells and CD11b+Gr1hi granulocytic lineage cells are recruited from the circulation by tumor-derived chemoattractants, which stimulate PI3-kinase γ (PI3Kγ-mediated integrin α4 activation and extravasation. We show here that PI3Kγ activates PLCγ, leading to RasGrp/CalDAG-GEF-I&II mediated, Rap1a-dependent activation of integrin α4β1, extravasation of monocytes and granulocytes, and inflammation-associated tumor progression. Genetic depletion of PLCγ, CalDAG-GEFI or II, Rap1a, or the Rap1 effector RIAM was sufficient to prevent integrin α4 activation by chemoattractants or activated PI3Kγ (p110γCAAX, while activated Rap (RapV12 promoted constitutive integrin activation and cell adhesion that could only be blocked by inhibition of RIAM or integrin α4β1. Similar to blockade of PI3Kγ or integrin α4β1, blockade of Rap1a suppressed both the recruitment of monocytes and granulocytes to tumors and tumor progression. These results demonstrate critical roles for a PI3Kγ-Rap1a-dependent pathway in integrin activation during tumor inflammation and suggest novel avenues for cancer therapy.

In Vitro Pre-Clinical Validation of Suicide Gene Modified Anti-CD33 Redirected Chimeric Antigen Receptor T-Cells for Acute Myeloid Leukemia.

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Kentaro Minagawa

Full Text Available Approximately fifty percent of patients with acute myeloid leukemia can be cured with current therapeutic strategies which include, standard dose chemotherapy for patients at standard risk of relapse as assessed by cytogenetic and molecular analysis, or high-dose chemotherapy with allogeneic hematopoietic stem cell transplant for high-risk patients. Despite allogeneic hematopoietic stem cell transplant about 25% of patients still succumb to disease relapse, therefore, novel strategies are needed to improve the outcome of patients with acute myeloid leukemia.We developed an immunotherapeutic strategy targeting the CD33 myeloid antigen, expressed in ~ 85-90% of patients with acute myeloid leukemia, using chimeric antigen receptor redirected T-cells. Considering that administration of CAR T-cells has been associated with cytokine release syndrome and other potential off-tumor effects in patients, safety measures were here investigated and reported. We genetically modified human activated T-cells from healthy donors or patients with acute myeloid leukemia with retroviral supernatant encoding the inducible Caspase9 suicide gene, a ΔCD19 selectable marker, and a humanized third generation chimeric antigen receptor recognizing human CD33. ΔCD19 selected inducible Caspase9-CAR.CD33 T-cells had a 75±3.8% (average ± standard error of the mean chimeric antigen receptor expression, were able to specifically lyse CD33+ targets in vitro, including freshly isolated leukemic blasts from patients, produce significant amount of tumor-necrosis-factor-alpha and interferon-gamma, express the CD107a degranulation marker, and proliferate upon antigen specific stimulation. Challenging ΔCD19 selected inducible Caspase9-CAR.CD33 T-cells with programmed-death-ligand-1 enriched leukemia blasts resulted in significant killing like observed for the programmed-death-ligand-1 negative leukemic blasts fraction. Since the administration of 10 nanomolar of a non

IDH1/2 Mutations Sensitize Acute Myeloid Leukemia to PARP Inhibition and This Is Reversed by IDH1/2-Mutant Inhibitors.

Science.gov (United States)

Molenaar, Remco J; Radivoyevitch, Tomas; Nagata, Yasunobu; Khurshed, Mohammed; Przychodzen, Bartolomiej; Makishima, Hideki; Xu, Mingjiang; Bleeker, Fonnet E; Wilmink, Johanna W; Carraway, Hetty E; Mukherjee, Sudipto; Sekeres, Mikkael A; van Noorden, Cornelis J F; Maciejewski, Jaroslaw P

2018-04-01

Purpose: Somatic mutations in IDH1/2 occur in approximately 20% of patients with myeloid neoplasms, including acute myeloid leukemia (AML). IDH1/2 MUT enzymes produce D -2-hydroxyglutarate ( D 2HG), which associates with increased DNA damage and improved responses to chemo/radiotherapy and PARP inhibitors in solid tumor cells. Whether this also holds true for IDH1/2 MUT AML is not known. Experimental Design: Well-characterized primary IDH1 MUT , IDH2 MUT , and IDH1/2 WT AML cells were analyzed for DNA damage and responses to daunorubicin, ionizing radiation, and PARP inhibitors. Results: IDH1/2 MUT caused increased DNA damage and sensitization to daunorubicin, irradiation, and the PARP inhibitors olaparib and talazoparib in AML cells. IDH1/2 MUT inhibitors protected against these treatments. Combined treatment with a PARP inhibitor and daunorubicin had an additive effect on the killing of IDH1/2 MUT AML cells. We provide evidence that the therapy sensitivity of IDH1/2 MUT cells was caused by D 2HG-mediated downregulation of expression of the DNA damage response gene ATM and not by altered redox responses due to metabolic alterations in IDH1/2 MUT cells. Conclusions: IDH1/2 MUT AML cells are sensitive to PARP inhibitors as monotherapy but especially when combined with a DNA-damaging agent, such as daunorubicin, whereas concomitant administration of IDH1/2 MUT inhibitors during cytotoxic therapy decrease the efficacy of both agents in IDH1/2 MUT AML. These results advocate in favor of clinical trials of PARP inhibitors either or not in combination with daunorubicin in IDH1/2 MUT AML. Clin Cancer Res; 24(7); 1705-15. ©2018 AACR . ©2018 American Association for Cancer Research.

CSF-1 Receptor Signaling in Myeloid Cells

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Stanley, E. Richard; Chitu, Violeta

2014-01-01

The CSF-1 receptor (CSF-1R) is activated by the homodimeric growth factors colony-stimulating factor-1 (CSF-1) and interleukin-34 (IL-34). It plays important roles in development and in innate immunity by regulating the development of most tissue macrophages and osteoclasts, of Langerhans cells of the skin, of Paneth cells of the small intestine, and of brain microglia. It also regulates the differentiation of neural progenitor cells and controls functions of oocytes and trophoblastic cells in the female reproductive tract. Owing to this broad tissue expression pattern, it plays a central role in neoplastic, inflammatory, and neurological diseases. In this review we summarize the evolution, structure, and regulation of expression of the CSF-1R gene. We review, the structures of CSF-1, IL-34, and the CSF-1R and the mechanism of ligand binding to and activation of the receptor. We further describe the pathways regulating macrophage survival, proliferation, differentiation, and chemotaxis downstream from the CSF-1R. PMID:24890514

Alantolactone selectively ablates acute myeloid leukemia stem and progenitor cells

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Yahui Ding

2016-09-01

Full Text Available Abstract Background The poor outcomes for patients diagnosed with acute myeloid leukemia (AML are largely attributed to leukemia stem cells (LSCs which are difficult to eliminate with conventional therapy and responsible for relapse. Thus, new therapeutic strategies which could selectively target LSCs in clinical leukemia treatment and avoid drug resistance are urgently needed. However, only a few small molecules have been reported to show anti-LSCs activity. Methods The aim of the present study was to identify alantolactone as novel agent that can ablate acute myeloid leukemia stem and progenitor cells from AML patient specimens and evaluate the anticancer activity of alantolactone in vitro and in vivo. Results The present study is the first to demonstrate that alantolactone, a prominent eudesmane-type sesquiterpene lactone, could specifically ablate LSCs from AML patient specimens. Furthermore, in comparison to the conventional chemotherapy drug, cytosine arabinoside (Ara-C, alantolactone showed superior effects of leukemia cytotoxicity while sparing normal hematopoietic cells. Alantolactone induced apoptosis with a dose-dependent manner by suppression of NF-kB and its downstream target proteins. DMA-alantolactone, a water-soluble prodrug of alantolactone, could suppress tumor growth in vivo. Conclusions Based on these results, we propose that alantolactone may represent a novel LSCs-targeted therapy and eudesmane-type sesquiterpene lactones offer a new scaffold for drug discovery towards anti-LSCs agents.

Caracterización de la expresión de nCD64 en neutrófilos y de los niveles de s-TREM-1 y HMGB-1 en pacientes con sospecha de infección admitidos en el departamento de emergencias

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Sergio Velásquez

2013-12-01

Full Text Available Introducción. El receptor CD64, receptor soluble ‘desencadenador’ expresado en células mieloides (sTREM-1 y la proteína del grupo Box-1 de alta movilidad (HMGB-1, se han propuesto como mediadores en la sepsis. Objetivo. Evaluar el valor pronóstico de estos marcadores en pacientes con sospecha de infección, recientemente admitidos en un departamento de emergencias. Materiales y métodos. Se incluyeron en el estudio pacientes que consultaron al hospital con sospecha de infección. Se analizó la base de datos clínica, el puntaje SOFA, el puntaje APACHE II, los niveles de HMGB-1, los niveles de sTREM-1 y los niveles de nCD64. Se determinaron las concentraciones en suero de HMGB-1 y sTREM-1, usando kits de ELISA disponibles comercialmente, y la de CD64 se midió por citometría de flujo. Resultados. Se analizaron 579 pacientes con sospecha de infección al ingreso. La edad media fue de 50 años (rango intercuartílico=35-68, y 11,1 % (n=64 murieron durante el seguimiento de 28 días. El diagnóstico más frecuente en el momento del ingreso fue neumonía adquirida en la comunidad, en 23 % (n=133 de los pacientes, seguida de infección de tejidos blandos, en 16,6 % (n=96, e infección urinaria, en 15 % (n=87. Después de un análisis multivariado, no hubo asociación significativa entre ningún biomarcador y la mortalidad a los 28 días. Conclusión. Los resultados sugieren que en el contexto de un departamento de emergencias de tercer nivel de una ciudad latinoamericana típica, los tres marcadores evaluados no ofrecieron ninguna ventaja en el pronóstico de infección. La búsqueda de marcadores pronósticos más confiables en estadios tempranos de la infección aún continúa abierta.   doi: http://dx.doi.org/10.7705/biomedica.v33i4.805

Mac-1low early myeloid cells in the bone marrow-derived SP fraction migrate into injured skeletal muscle and participate in muscle regeneration

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Ojima, Koichi; Uezumi, Akiyoshi; Miyoshi, Hiroyuki; Masuda, Satoru; Morita, Yohei; Fukase, Akiko; Hattori, Akihito; Nakauchi, Hiromitsu; Miyagoe-Suzuki, Yuko; Takeda, Shin'ichi

2004-01-01

Recent studies have shown that bone marrow (BM) cells, including the BM side population (BM-SP) cells that enrich hematopoietic stem cells (HSCs), are incorporated into skeletal muscle during regeneration, but it is not clear how and what kinds of BM cells contribute to muscle fiber regeneration. We found that a large number of SP cells migrated from BM to muscles following injury in BM-transplanted mice. These BM-derived SP cells in regenerating muscles expressed different surface markers from those of HSCs and could not reconstitute the mouse blood system. BM-derived SP/Mac-1 low cells increased in number in regenerating muscles following injury. Importantly, our co-culture studies with activated satellite cells revealed that this fraction carried significant potential for myogenic differentiation. By contrast, mature inflammatory (Mac-1 high ) cells showed negligible myogenic activities. Further, these BM-derived SP/Mac-1 low cells gave rise to mononucleate myocytes, indicating that their myogenesis was not caused by stochastic fusion with host myogenic cells, although they required cell-to-cell contact with myogenic cells for muscle differentiation. Taken together, our data suggest that neither HSCs nor mature inflammatory cells, but Mac-1 low early myeloid cells in the BM-derived SP fraction, play an important role in regenerating skeletal muscles

Tumor-educated myeloid cells: impact the micro- and macroenvironment.

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Becker, Jürgen C

2014-03-01

Immune escape mechanisms of cancers include some of the mechanisms normally used for immune homeostasis, particular those preventing autoimmunity; one of these is the polarisation of myeloid cells. Thereby, tumors, i.e. the cancerous and stromal cells, also condition distant sites like spleen and bone marrow via soluble factors and membrane vesicles such as exosomes in order to create a tumor-educated macroenvironment. Albeit these mechanisms are currently in the focus of (tumor-)immunologic research, the first evidence had been published almost 40 years ago. One of these early reports will be discussed here. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

A Rapid Culture Technique Produces Functional Dendritic-Like Cells from Human Acute Myeloid Leukemia Cell Lines

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Jian Ning

2011-01-01

Full Text Available Most anti-cancer immunotherapeutic strategies involving dendritic cells (DC as vaccines rely upon the adoptive transfer of DC loaded with exogenous tumour-peptides. This study utilized human acute myeloid leukemia (AML cells as progenitors from which functional dendritic-like antigen presenting cells (DLC were generated, that constitutively express tumour antigens for recognition by CD8+ T cells. DLC were generated from AML cell lines KG-1 and MUTZ-3 using rapid culture techniques and appropriate cytokines. DLC were evaluated for their cell-surface phenotype, antigen uptake and ability to stimulate allogeneic responder cell proliferation, and production of IFN-γ; compared with DC derived from normal human PBMC donors. KG-1 and MUTZ-3 DLC increased expression of CD80, CD83, CD86, and HLA-DR, and MUTZ-3 DLC downregulated CD14 and expressed CD1a. Importantly, both KG-1 and MUTZ-3-derived DLC promoted proliferation of allogeneic responder cells more efficiently than unmodified cells; neither cells incorporated FITC-labeled dextran, but both stimulated IFN-γ production from responding allogeneic CD8+ T cells. Control DC produced from PBMC using the FastDC culture also expressed high levels of critical cell surface ligands and demonstrated good APC function. This paper indicates that functional DLC can be cultured from the AML cell lines KG-1 and MUTZ-3, and FastDC culture generates functional KG-1 DLC.

Chronic inflammation triggered by the NLRP3 inflammasome in myeloid cells promotes growth plate dysplasia by mesenchymal cells.

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Wang, Chun; Xu, Can-Xin; Alippe, Yael; Qu, Chao; Xiao, Jianqiu; Schipani, Ernestina; Civitelli, Roberto; Abu-Amer, Yousef; Mbalaviele, Gabriel

2017-07-07

Skeletal complications are common features of neonatal-onset multisystem inflammatory disease (NOMID), a disorder caused by NLRP3-activating mutations. NOMID mice in which NLRP3 is activated globally exhibit several characteristics of the human disease, including systemic inflammation and cartilage dysplasia, but the mechanisms of skeletal manifestations remain unknown. In this study, we find that activation of NLRP3 in myeloid cells, but not mesenchymal cells triggers chronic inflammation, which ultimately, causes growth plate and epiphyseal dysplasia in mice. These responses are IL-1 signaling-dependent, but independent of PARP1, which also functions downstream of NLRP3 and regulates skeletal homeostasis. Mechanistically, inflammation causes severe anemia and hypoxia in the bone environment, yet down-regulates the HIF-1α pathway in chondrocytes, thereby promoting the demise of these cells. Thus, activation of NLRP3 in hematopoietic cells initiates IL-1β-driven paracrine cascades, which promote abnormal growth plate development in NOMID mice.

A20 (Tnfaip3 deficiency in myeloid cells protects against influenza A virus infection.

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Jonathan Maelfait

Full Text Available The innate immune response provides the first line of defense against viruses and other pathogens by responding to specific microbial molecules. Influenza A virus (IAV produces double-stranded RNA as an intermediate during the replication life cycle, which activates the intracellular pathogen recognition receptor RIG-I and induces the production of proinflammatory cytokines and antiviral interferon. Understanding the mechanisms that regulate innate immune responses to IAV and other viruses is of key importance to develop novel therapeutic strategies. Here we used myeloid cell specific A20 knockout mice to examine the role of the ubiquitin-editing protein A20 in the response of myeloid cells to IAV infection. A20 deficient macrophages were hyperresponsive to double stranded RNA and IAV infection, as illustrated by enhanced NF-κB and IRF3 activation, concomitant with increased production of proinflammatory cytokines, chemokines and type I interferon. In vivo this was associated with an increased number of alveolar macrophages and neutrophils in the lungs of IAV infected mice. Surprisingly, myeloid cell specific A20 knockout mice are protected against lethal IAV infection. These results challenge the general belief that an excessive host proinflammatory response is associated with IAV-induced lethality, and suggest that under certain conditions inhibition of A20 might be of interest in the management of IAV infections.

CXCL17 expression by tumor cells recruits CD11b+Gr1 high F4/80- cells and promotes tumor progression.

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Aya Matsui

Full Text Available BACKGROUND: Chemokines are involved in multiple aspects of pathogenesis and cellular trafficking in tumorigenesis. In this study, we report that the latest member of the C-X-C-type chemokines, CXCL17 (DMC/VCC-1, recruits immature myeloid-derived cells and enhances early tumor progression. METHODOLOGY/PRINCIPAL FINDINGS: CXCL17 was preferentially expressed in some aggressive types of gastrointestinal, breast, and lung cancer cells. CXCL17 expression did not impart NIH3T3 cells with oncogenic potential in vitro, but CXCL17-expressing NIH3T3 cells could form vasculature-rich tumors in immunodeficient mice. Our data showed that CXCL17-expressing tumor cells increased immature CD11b(+Gr1(+ myeloid-derived cells at tumor sites in mice and promoted CD31(+ tumor angiogenesis. Extensive chemotactic assays proved that CXCL17-responding cells were CD11b(+Gr1(highF4/80(- cells (≈ 90% with a neutrophil-like morphology in vitro. Although CXCL17 expression could not increase the number of CD11b(+Gr1(+ cells in tumor-burdened SCID mice or promote metastases of low metastatic colon cancer cells, the existence of CXCL17-responding myeloid-derived cells caused a striking enhancement of xenograft tumor formation. CONCLUSIONS/SIGNIFICANCE: These results suggest that aberrant expression of CXCL17 in tumor cells recruits immature myeloid-derived cells and promotes tumor progression through angiogenesis.

NK-, NKT- and CD8-Derived IFNγ Drives Myeloid Cell Activation and Erythrophagocytosis, Resulting in Trypanosomosis-Associated Acute Anemia.

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Jennifer Cnops

2015-06-01

Full Text Available African trypanosomes are the causative agents of Human African Trypanosomosis (HAT/Sleeping Sickness and Animal African Trypanosomosis (AAT/Nagana. A common hallmark of African trypanosome infections is inflammation. In murine trypanosomosis, the onset of inflammation occurs rapidly after infection and is manifested by an influx of myeloid cells in both liver and spleen, accompanied by a burst of serum pro-inflammatory cytokines. Within 48 hours after reaching peak parasitemia, acute anemia develops and the percentage of red blood cells drops by 50%. Using a newly developed in vivo erythrophagocytosis assay, we recently demonstrated that activated cells of the myeloid phagocytic system display enhanced erythrophagocytosis causing acute anemia. Here, we aimed to elucidate the mechanism and immune pathway behind this phenomenon in a murine model for trypanosomosis. Results indicate that IFNγ plays a crucial role in the recruitment and activation of erythrophagocytic myeloid cells, as mice lacking the IFNγ receptor were partially protected against trypanosomosis-associated inflammation and acute anemia. NK and NKT cells were the earliest source of IFNγ during T. b. brucei infection. Later in infection, CD8+ and to a lesser extent CD4+ T cells become the main IFNγ producers. Cell depletion and transfer experiments indicated that during infection the absence of NK, NKT and CD8+ T cells, but not CD4+ T cells, resulted in a reduced anemic phenotype similar to trypanosome infected IFNγR-/- mice. Collectively, this study shows that NK, NKT and CD8+ T cell-derived IFNγ is a critical mediator in trypanosomosis-associated pathology, driving enhanced erythrophagocytosis by myeloid phagocytic cells and the induction of acute inflammation-associated anemia.

Drug screen in patient cells suggests quinacrine to be repositioned for treatment of acute myeloid leukemia

International Nuclear Information System (INIS)

Eriksson, A; Österroos, A; Hassan, S; Gullbo, J; Rickardson, L; Jarvius, M; Nygren, P; Fryknäs, M; Höglund, M; Larsson, R

2015-01-01

To find drugs suitable for repositioning for use against leukemia, samples from patients with chronic lymphocytic, acute myeloid and lymphocytic leukemias as well as peripheral blood mononuclear cells (PBMC) were tested in response to 1266 compounds from the LOPAC 1280 library (Sigma). Twenty-five compounds were defined as hits with activity in all leukemia subgroups (<50% cell survival compared with control) at 10 μM drug concentration. Only one of these compounds, quinacrine, showed low activity in normal PBMCs and was therefore selected for further preclinical evaluation. Mining the NCI-60 and the NextBio databases demonstrated leukemia sensitivity and the ability of quinacrine to reverse myeloid leukemia gene expression. Mechanistic exploration was performed using the NextBio bioinformatic software using gene expression analysis of drug exposed acute myeloid leukemia cultures (HL-60) in the database. Analysis of gene enrichment and drug correlations revealed strong connections to ribosomal biogenesis nucleoli and translation initiation. The highest drug–drug correlation was to ellipticine, a known RNA polymerase I inhibitor. These results were validated by additional gene expression analysis performed in-house. Quinacrine induced early inhibition of protein synthesis supporting these predictions. The results suggest that quinacrine have repositioning potential for treatment of acute myeloid leukemia by targeting of ribosomal biogenesis

The DNA Inflammasome in Human Myeloid Cells Is Initiated by a STING-Cell Death Program Upstream of NLRP3

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Gaidt, Moritz M.; Ebert, Thomas S.; Chauhan, Dhruv; Ramshorn, Katharina; Pinci, Francesca; Zuber, Sarah; O’Duill, Fionan; Schmid-Burgk, Jonathan L.; Hoss, Florian; Buhmann, Raymund; Wittmann, Georg; Latz, Eicke; Subklewe, Marion; Hornung, Veit

2018-01-01

Summary Detection of cytosolic DNA constitutes a central event in the context of numerous infectious and sterile inflammatory conditions. Recent studies have uncovered a bipartite mode of cytosolic DNA recognition, in which the cGAS-STING axis triggers antiviral immunity, whereas AIM2 triggers inflammasome activation. Here, we show that AIM2 is dispensable for DNA-mediated inflammasome activation in human myeloid cells. Instead, detection of cytosolic DNA by the cGAS-STING axis induces a cell death program initiating potassium efflux upstream of NLRP3. Forward genetics identified regulators of lysosomal trafficking to modulate this cell death program, and subsequent studies revealed that activated STING traffics to the lysosome, where it triggers membrane permeabilization and thus lysosomal cell death (LCD). Importantly, the cGAS-STING-NLRP3 pathway constitutes the default inflammasome response during viral and bacterial infections in human myeloid cells. We conclude that targeting the cGAS-STING-LCD-NLRP3 pathway will ameliorate pathology in inflammatory conditions that are associated with cytosolic DNA sensing. PMID:29033128

[An immunological approach to acute myeloid leukaemia].

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González, B; Bueno, D; Rubio, P M; San Román, S; Plaza, D; Sastre, A; García-Miguel, P; Fernández, L; Valentín, J; Martínez, I; Pérez-Martínez, A

2016-04-01

Acute myeloid leukaemia (AML) is the second haematological malignancy in the paediatric population, and one of the leading causes of childhood cancer mortality. Survival is currently around 60%, with no improvement in last decades, suggesting that new therapeutic approaches are needed. The anti-leukaemia effect mediated by the lymphocytes and natural killer (NK) cells of the immune system has been established in haematopoietic stem cell transplantation, and also as adoptive immunotherapy after consolidation chemotherapy schemes. A retrospective study was conducted on the clinical characteristics of patients diagnosed and treated for AML in our centre during 1996-2014. The mean fluorescence intensities of HLA-I, MICA/B and ULBP1-4, ligands for NK cell receptors, were also analysed in ten new diagnosed leukaemia cases, five myeloid and five lymphoid. A total of 67 patients were used in this analysis. With a median follow up of 25 months, the event-free survival was 62% (95% CI: 55-67). Secondary AML, non-M3 phenotype, and the absence of favourable cytogenetic markers had a lower survival. The probability of relapse was 38% (95% CI: 31-45). The expression of HLA-I and ULBP-4 was significantly lower in myeloid than in lymphoid blast cells. Our clinical results are similar to those described in the literature. Survival did not significantly change in recent decades, and the likelihood of relapse remains high. Myeloid blasts might be more susceptible to the cytotoxicity of NK cells through their lower expression of HLA-I. NK therapy strategies in minimal disease situation could be effective, as reported by other groups. Copyright © 2015 Asociación Española de Pediatría. Published by Elsevier España, S.L.U. All rights reserved.

Co-activation of AMPK and mTORC1 Induces Cytotoxicity in Acute Myeloid Leukemia

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Pierre Sujobert

2015-06-01

Full Text Available AMPK is a master regulator of cellular metabolism that exerts either oncogenic or tumor suppressor activity depending on context. Here, we report that the specific AMPK agonist GSK621 selectively kills acute myeloid leukemia (AML cells but spares normal hematopoietic progenitors. This differential sensitivity results from a unique synthetic lethal interaction involving concurrent activation of AMPK and mTORC1. Strikingly, the lethality of GSK621 in primary AML cells and AML cell lines is abrogated by chemical or genetic ablation of mTORC1 signaling. The same synthetic lethality between AMPK and mTORC1 activation is established in CD34-positive hematopoietic progenitors by constitutive activation of AKT or enhanced in AML cells by deletion of TSC2. Finally, cytotoxicity in AML cells from GSK621 involves the eIF2α/ATF4 signaling pathway that specifically results from mTORC1 activation. AMPK activation may represent a therapeutic opportunity in mTORC1-overactivated cancers.

Impact of Allogeneic Stem Cell Transplantation in First Complete Remission in Acute Myeloid Leukemia

DEFF Research Database (Denmark)

Østgård, Lene Sofie Granfeldt; Lund, Jennifer L; Nørgaard, Jan Maxwell

2018-01-01

To examine the outcome of allogeneic stem cell transplantation (HSCT) in first complete remission (CR1) compared to chemotherapy alone in a population-based setting, we identified a cohort of acute myeloid leukemia (AML) patients aged 15-70 years diagnosed between 2000-2014 in Denmark. Using...... the Danish National Acute Leukemia Registry, we compared relapse risk, relapse-free survival (RFS), and overall survival between patients with non-favorable cytogenetic features receiving post-remission therapy with conventional chemotherapy-only versus those undergoing HSCT in CR1. To minimize immortal time...

BCR-ABL1- positive chronic myeloid leukemia with erythrocytosis presenting as polycythemia vera: a case report.

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Cornea, Mihaela I Precup; Levrat, Emmanuel; Pugin, Paul; Betticher, Daniel C

2015-04-08

The World Health Organization classification of chronic myeloproliferative disease encompasses eight entities of bone marrow neoplasms, among them Breakpoint cluster region-Abelson murine leukemia viral oncogene homolog 1-positive chronic myeloid leukemia and polycythemia vera. Polycythemia vera requires, in the majority of cases (95%), the negativity of Breakpoint cluster region-Abelson murine leukemia viral oncogene homolog 1 rearrangement and the presence of the Janus kinase 2 mutation. We report a case of erythrocytosis as the primary manifestation of a chronic myeloid leukemia, with the presence of the Philadelphia chromosome and the Breakpoint cluster region-Abelson murine leukemia viral oncogene homolog 1 fusion gene, and in the absence of any Janus kinase 2 mutation. A 68-year-old Caucasian woman, with a history of cigarette consumption and obstructive sleep apnoea syndrome (undergoing continuous positive airway pressure treatment) had presented to our institution with fatigue and a hemoglobin level of 18.6g/L, with slight leukocytosis at 16G/L, and no other anomalies on her complete blood cell count. Examination of her arterial blood gases found only a slight hypoxemia; erythropoietin and ferritin levels were very low and could not explain a secondary erythrocytosis. Further analyses revealed the absence of any Janus kinase 2 mutation, thus excluding polycythemia vera. Taken together with a high vitamin B12 level, we conducted a Breakpoint cluster region-Abelson murine leukemia viral oncogene homolog 1 gene analysis and bone marrow cytogenetic analysis, both of which returned positive, leading to the diagnosis of chronic myeloid leukemia. To date, this case is the first description of a Breakpoint cluster region-Abelson murine leukemia viral oncogene homolog 1-positive chronic myeloid leukemia, presenting with erythrocytosis as the initial manifestation, and mimicking a Janus kinase 2 V617F-negative polycythemia vera. Her impressive response to imatinib

GATA Factor-Dependent Positive-Feedback Circuit in Acute Myeloid Leukemia Cells

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Koichi R. Katsumura

2016-08-01

Full Text Available The master regulatory transcription factor GATA-2 triggers hematopoietic stem and progenitor cell generation. GATA2 haploinsufficiency is implicated in myelodysplastic syndrome (MDS and acute myeloid leukemia (AML, and GATA2 overexpression portends a poor prognosis for AML. However, the constituents of the GATA-2-dependent genetic network mediating pathogenesis are unknown. We described a p38-dependent mechanism that phosphorylates GATA-2 and increases GATA-2 target gene activation. We demonstrate that this mechanism establishes a growth-promoting chemokine/cytokine circuit in AML cells. p38/ERK-dependent GATA-2 phosphorylation facilitated positive autoregulation of GATA2 transcription and expression of target genes, including IL1B and CXCL2. IL-1β and CXCL2 enhanced GATA-2 phosphorylation, which increased GATA-2-mediated transcriptional activation. p38/ERK-GATA-2 stimulated AML cell proliferation via CXCL2 induction. As GATA2 mRNA correlated with IL1B and CXCL2 mRNAs in AML-M5 and high expression of these genes predicted poor prognosis of cytogenetically normal AML, we propose that the circuit is functionally important in specific AML contexts.

An inhibitory switch derepressed by pbx, hox, and Meis/Prep1 partners regulates DNA-binding by pbx1 and E2a-pbx1 and is dispensable for myeloid immortalization by E2a-pbx1.

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Calvo, K R; Knoepfler, P; McGrath, S; Kamps, M P

1999-12-23

The Pbx/Exd family of homeodomain (HD) proteins contribute to the transcriptional and developmental roles of other Hox and Meis/Prep1/Hth HD proteins through heterodimer formation. E2a-Pbx1 is an oncogenic derrivative of Pbx1 produced by the t(1;19) translocation in pediatric pre-B cell acute lymphoblastic leukemia. E2a-Pbx1 heterodimerizes with Hox but not with Meis/Prep1 proteins, produces acute myeloid leukemia in mice, and blocks differentiation of cultured murine myeloid progenitors. Here, we characterize negative and positive regulatory sequences that flank the Pbx1 HD and determine their importance for myeloid immortalization by E2a-Pbx1. A 25 residue predicted alpha helix preceding the Pbx1 HD bound the HD and prevented both its binding to DNA and its ability to heterodimerize with Hox proteins. Addition of 39 residues N-terminal to this inhibitory helix exposed a Pbx dimerization interface that orchestrated cooperative DNA-binding of E2a-Pbx1 and all Pbx proteins as homodimers and heterdimers. Sequences inhibiting DNA-binding and mediating Pbx dimerization coincided with those reported to have nuclear export function. An additional 103 residues N-terminal to the Pbx dimerization interface restored heterodimerization with Hox and Meis1/Prep1 proteins. This negative switch domain - comprised of the inhibitory helix and N-terminal regions required for its partner-mediated derepression - was dispensable for myeloid immortalization by E2a-Pbx1. While stabilizing the heterodimer, the 310 helix C-terminal to the Pbx1 HD was also dispensable for the ability of E2a-Pbx1 to heterodimerize with Hox proteins and immortalize myeloblasts. Retention of myeloid immortalization by E2a-Pbx1 proteins lacking all Pbx1 sequences N- or C-terminal to the HD indicates that Hox proteins, or a yet undefined factor that binds the Pbx1 HD and derepresses DNA-binding by the HD, cooperate with E2a-Pbx1 in myeloid immortalization.

Genes of cell-cell interactions, chemotherapy detoxification and apoptosis are induced during chemotherapy of acute myeloid leukemia

International Nuclear Information System (INIS)

Øyan, Anne Margrete; Ånensen, Nina; Bø, Trond Hellem; Stordrange, Laila; Jonassen, Inge; Bruserud, Øystein; Kalland, Karl-Henning; Gjertsen, Bjørn Tore

2009-01-01

The molecular changes in vivo in acute myeloid leukemia cells early after start of conventional genotoxic chemotherapy are incompletely understood, and it is not known if early molecular modulations reflect clinical response. The gene expression was examined by whole genome 44 k oligo microarrays and 12 k cDNA microarrays in peripheral blood leukocytes collected from seven leukemia patients before treatment, 2–4 h and 18–24 h after start of chemotherapy and validated by real-time quantitative PCR. Statistically significantly upregulated genes were classified using gene ontology (GO) terms. Parallel samples were examined by flow cytometry for apoptosis by annexin V-binding and the expression of selected proteins were confirmed by immunoblotting. Significant differential modulation of 151 genes were found at 4 h after start of induction therapy with cytarabine and anthracycline, including significant overexpression of 31 genes associated with p53 regulation. Within 4 h of chemotherapy the BCL2/BAX and BCL2/PUMA ratio were attenuated in proapoptotic direction. FLT3 mutations indicated that non-responders (5/7 patients, 8 versus 49 months survival) are characterized by a unique gene response profile before and at 4 h. At 18–24 h after chemotherapy, the gene expression of p53 target genes was attenuated, while genes involved in chemoresistance, cytarabine detoxification, chemokine networks and T cell receptor were prominent. No signs of apoptosis were observed in the collected cells, suggesting the treated patients as a physiological source of pre-apoptotic cells. Pre-apoptotic gene expression can be monitored within hours after start of chemotherapy in patients with acute myeloid leukemia, and may be useful in future determination of therapy responders. The low number of patients and the heterogeneity of acute myeloid leukemia limited the identification of gene expression predictive of therapy response. Therapy-induced gene expression reflects the complex

Myeloid-derived suppressor cells as a potential therapy for experimental autoimmune myasthenia gravis.

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Li, Yan; Tu, Zhidan; Qian, Shiguang; Fung, John J; Markowitz, Sanford D; Kusner, Linda L; Kaminski, Henry J; Lu, Lina; Lin, Feng

2014-09-01

We recently demonstrated that hepatic stellate cells induce the differentiation of myeloid-derived suppressor cells (MDSCs) from myeloid progenitors. In this study, we found that adoptive transfer of these MDSCs effectively reversed disease progression in experimental autoimmune myasthenia gravis (EAMG), a T cell-dependent and B cell-mediated model for myasthenia gravis. In addition to ameliorated disease severity, MDSC-treated EAMG mice showed suppressed acetylcholine receptor (AChR)-specific T cell responses, decreased levels of serum anti-AChR IgGs, and reduced complement activation at the neuromuscular junctions. Incubating MDSCs with B cells activated by anti-IgM or anti-CD40 Abs inhibited the proliferation of these in vitro-activated B cells. Administering MDSCs into mice immunized with a T cell-independent Ag inhibited the Ag-specific Ab production in vivo. MDSCs directly inhibit B cells through multiple mechanisms, including PGE2, inducible NO synthase, and arginase. Interestingly, MDSC treatment in EAMG mice does not appear to significantly inhibit their immune response to a nonrelevant Ag, OVA. These results demonstrated that hepatic stellate cell-induced MDSCs concurrently suppress both T and B cell autoimmunity, leading to effective treatment of established EAMG, and that the MDSCs inhibit AChR-specific immune responses at least partially in an Ag-specific manner. These data suggest that MDSCs could be further developed as a novel approach to treating myasthenia gravis and, even more broadly, other diseases in which T and B cells are involved in pathogenesis. Copyright © 2014 by The American Association of Immunologists, Inc.

Outcomes following splenectomy in patients with myeloid neoplasms.

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Rialon, Kristy L; Speicher, Paul J; Ceppa, Eugene P; Rendell, Victoria R; Vaslef, Steven N; Beaven, Anne; Tyler, Douglas S; Blazer, Dan G

2015-03-15

Myeloid neoplasms are classified into five major categories. These patients may develop splenomegaly and require splenectomy to alleviate mechanical symptoms, to ameliorate transfusion-dependent cytopenias, or to enhance stem cell transplantation. The objective of this study was to determine which clinical variables significantly impacted morbidity, mortality, and survival in patients with myeloid neoplasms undergoing splenectomy, and to determine if operative outcomes have improved over time. The records of all patients with myeloid neoplasms undergoing splenectomy from 1993 to 2010 were retrospectively reviewed. Eighty-nine patients (n = 89) underwent splenectomy for myeloid neoplasms. Over half of patients who had symptoms preoperatively had resolution of their symptoms post-splenectomy. The morbidity rate was 38%, with the most common complications being bleeding (14%) or infection (20%). Thirty-day mortality rate was 18% and median survival after splenectomy was 278 days. Decreased survival was associated with a diagnosis of myelodysplastic syndrome/myeloproliferative neoplasm, anemia, abnormal white blood cell count, and hypoalbuminemia. Patients who underwent stem cell transplantation did not show an increased risk for morbidity or mortality. Patients with myeloid neoplasms have a poor prognosis after splenectomy and the decision to operate is a difficult one, associated with high morbidity and mortality. © 2014 Wiley Periodicals, Inc.

Impaired B cell immunity in acute myeloid leukemia patients after chemotherapy.

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Goswami, Meghali; Prince, Gabrielle; Biancotto, Angelique; Moir, Susan; Kardava, Lela; Santich, Brian H; Cheung, Foo; Kotliarov, Yuri; Chen, Jinguo; Shi, Rongye; Zhou, Huizhi; Golding, Hana; Manischewitz, Jody; King, Lisa; Kunz, Lauren M; Noonan, Kimberly; Borrello, Ivan M; Smith, B Douglas; Hourigan, Christopher S

2017-07-10

Changes in adaptive immune cells after chemotherapy in adult acute myeloid leukemia (AML) may have implications for the success of immunotherapy. This study was designed to determine the functional capacity of the immune system in adult patients with AML who have completed chemotherapy and are potential candidates for immunotherapy. We used the response to seasonal influenza vaccination as a surrogate for the robustness of the immune system in 10 AML patients in a complete remission post-chemotherapy and performed genetic, phenotypic, and functional characterization of adaptive immune cell subsets. Only 2 patients generated protective titers in response to vaccination, and a majority of patients had abnormal frequencies of transitional and memory B-cells. B-cell receptor sequencing showed a B-cell repertoire with little evidence of somatic hypermutation in most patients. Conversely, frequencies of T-cell populations were similar to those seen in healthy controls, and cytotoxic T-cells demonstrated antigen-specific activity after vaccination. Effector T-cells had increased PD-1 expression in AML patients least removed from chemotherapy. Our results suggest that while some aspects of cellular immunity recover quickly, humoral immunity is incompletely reconstituted in the year following intensive cytotoxic chemotherapy for AML. The observed B-cell abnormalities may explain the poor response to vaccination often seen in AML patients after chemotherapy. Furthermore, the uncoupled recovery of B-cell and T-cell immunity and increased PD-1 expression shortly after chemotherapy might have implications for the success of several modalities of immunotherapy.

Oral myeloid cells uptake allergoids coupled to mannan driving Th1/Treg responses upon sublingual delivery in mice.

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Soria, I; López-Relaño, J; Viñuela, M; Tudela, J-I; Angelina, A; Benito-Villalvilla, C; Díez-Rivero, C M; Cases, B; Manzano, A I; Fernández-Caldas, E; Casanovas, M; Palomares, O; Subiza, J L

2018-04-01

Polymerized allergoids coupled to nonoxidized mannan (PM-allergoids) may represent novel vaccines targeting dendritic cells (DCs). PM-allergoids are better captured by DCs than native allergens and favor Th1/Treg cell responses upon subcutaneous injection. Herein we have studied in mice the in vivo immunogenicity of PM-allergoids administered sublingually in comparison with native allergens. Three immunization protocols (4-8 weeks long) were used in Balb/c mice. Serum antibody levels were tested by ELISA. Cell responses (proliferation, cytokines, and Tregs) were assayed by flow cytometry in spleen and lymph nodes (LNs). Allergen uptake was measured by flow cytometry in myeloid sublingual cells. A quick antibody response and higher IgG2a/IgE ratio were observed with PM-allergoids. Moreover, stronger specific proliferative responses were seen in both submandibular LNs and spleen cells assayed in vitro. This was accompanied by a higher IFNγ/IL-4 ratio with a quick IL-10 production by submandibular LN cells. An increase in CD4 + CD25 high FOXP3 + Treg cells was detected in LNs and spleen of mice treated with PM-allergoids. These allergoids were better captured than native allergens by antigen-presenting (CD45 + MHC-II + ) cells obtained from the sublingual mucosa, including DCs (CD11b + ) and macrophages (CD64 + ). Importantly, all the differential effects induced by PM-allergoids were abolished when using oxidized instead of nonoxidized PM-allergoids. Our results demonstrate for the first time that PM-allergoids administered through the sublingual route promote the generation of Th1 and FOXP3 + Treg cells in a greater extent than native allergens by mechanisms that might well involve their better uptake by oral antigen-presenting cells. © 2018 The Authors. Allergy Published by John Wiley & Sons Ltd.

Interleukin-33-Activated Islet-Resident Innate Lymphoid Cells Promote Insulin Secretion through Myeloid Cell Retinoic Acid Production.

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Dalmas, Elise; Lehmann, Frank M; Dror, Erez; Wueest, Stephan; Thienel, Constanze; Borsigova, Marcela; Stawiski, Marc; Traunecker, Emmanuel; Lucchini, Fabrizio C; Dapito, Dianne H; Kallert, Sandra M; Guigas, Bruno; Pattou, Francois; Kerr-Conte, Julie; Maechler, Pierre; Girard, Jean-Philippe; Konrad, Daniel; Wolfrum, Christian; Böni-Schnetzler, Marianne; Finke, Daniela; Donath, Marc Y

2017-11-21

Pancreatic-islet inflammation contributes to the failure of β cell insulin secretion during obesity and type 2 diabetes. However, little is known about the nature and function of resident immune cells in this context or in homeostasis. Here we show that interleukin (IL)-33 was produced by islet mesenchymal cells and enhanced by a diabetes milieu (glucose, IL-1β, and palmitate). IL-33 promoted β cell function through islet-resident group 2 innate lymphoid cells (ILC2s) that elicited retinoic acid (RA)-producing capacities in macrophages and dendritic cells via the secretion of IL-13 and colony-stimulating factor 2. In turn, local RA signaled to the β cells to increase insulin secretion. This IL-33-ILC2 axis was activated after acute β cell stress but was defective during chronic obesity. Accordingly, IL-33 injections rescued islet function in obese mice. Our findings provide evidence that an immunometabolic crosstalk between islet-derived IL-33, ILC2s, and myeloid cells fosters insulin secretion. Copyright © 2017 Elsevier Inc. All rights reserved.

Radiation response of mouse lymphoid and myeloid cell lines. Pt. 3

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Radford, I.R.; Murphy, T.K.

1994-01-01

The authors have examined the timing of γ-irradiation-induced death in relation to cell cycle progression using a panel of mouse lymphoid or myeloid cell lines. Death was found to occur immediately after irradiation ('rapid interphase' death), or after arrest in G 2 phase ('delayed interphase' death), or following one or more mitoses ('mitotic/delayed mitotic' death). In part II of this series of papers the authors demonstrated the occurrence of radiation-induced apoptosis in all these cell lines. Several of the cell lines showed different timing of death dependent upon the radiation dose used. These differences in the timing of radiation-induced death are shown to be useful indicators of the relative radiosensitivity of haematopoietic cell lines. (author)

Tif1γ regulates the TGF-β1 receptor and promotes physiological aging of hematopoietic stem cells.

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Quéré, Ronan; Saint-Paul, Laetitia; Carmignac, Virginie; Martin, Romain Z; Chrétien, Marie-Lorraine; Largeot, Anne; Hammann, Arlette; Pais de Barros, Jean-Paul; Bastie, Jean-Noël; Delva, Laurent

2014-07-22

The hematopoietic system declines with age. Myeloid-biased differentiation and increased incidence of myeloid malignancies feature aging of hematopoietic stem cells (HSCs), but the mechanisms involved remain uncertain. Here, we report that 4-mo-old mice deleted for transcription intermediary factor 1γ (Tif1γ) in HSCs developed an accelerated aging phenotype. To reinforce this result, we also show that Tif1γ is down-regulated in HSCs during aging in 20-mo-old wild-type mice. We established that Tif1γ controls TGF-β1 receptor (Tgfbr1) turnover. Compared with young HSCs, Tif1γ(-/-) and old HSCs are more sensitive to TGF-β signaling. Importantly, we identified two populations of HSCs specifically discriminated by Tgfbr1 expression level and provided evidence of the capture of myeloid-biased (Tgfbr1(hi)) and myeloid-lymphoid-balanced (Tgfbr1(lo)) HSCs. In conclusion, our data provide a new paradigm for Tif1γ in regulating the balance between lymphoid- and myeloid-derived HSCs through TGF-β signaling, leading to HSC aging.

Reduction of myeloid suppressor cell derived nitric oxide provides a mechanistic basis of lead enhancement of alloreactive CD4+ T cell proliferation

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Farrer, David G.; Hueber, Sara; Laiosa, Michael D.; Eckles, Kevin G.; McCabe, Michael J.

2008-01-01

The persistent environmental toxicant and immunomodulator, lead (Pb), has been proposed to directly target CD4 + T cells. However, our studies suggest that CD4 + T cells are an important functional, yet indirect target. In order to identify the direct target of Pb in the immune system and the potential mechanism of Pb-induced immunotoxicity, myeloid suppressor cells (MSCs) were evaluated for their ability to modulate CD4 + T cell proliferation after Pb exposure. Myeloid suppressor cells regulate the adaptive immune response, in part, by inhibiting the proliferation of CD4 + T cells. It is thought that the mechanism of MSC-dependent regulation involves the release of the bioactive gas, nitric oxide (NO), blocking cell signaling cascades downstream of the IL-2 receptor and thus preventing T cells from entering cell-cycle. In mixed lymphocyte culture (MLC), increasing numbers of MSCs suppressed T cell proliferation in a dose-dependent manner, and this suppression is strikingly abrogated with 5 μM lead (Pb) treatment. The Pb-sensitive MSC population is CD11b + , GR1 + and CD11c - and thus phenotypically consistent with MSCs described in other literature. Inhibition of NO-synthase (NOS), the enzyme responsible for the production of NO, enhanced alloreactive T cell proliferation in MLC. Moreover, Pb attenuated NO production in MLC, and exogenous replacement of NO restored suppression in the presence of Pb. Significantly, MSC from iNOS-/- mice were unable to suppress T cell proliferation. An MSC-derived cell line (MSC-1) also suppressed T cell proliferation in MLC, and Pb disrupted this suppression by attenuating NO production. Additionally, Pb disrupted NO production in MSC-1 cells in response to treatment with interferon-γ (IFN-γ) and LPS or in response to concanavalin A-stimulated splenocytes. However, neither the abundance of protein nor levels of mRNA for the inducible isoform of NOS (iNOS) were altered with Pb treatment. Taken together these data suggest that Pb

Targeting BCL2 Family in Human Myeloid Dendritic Cells: A Challenge to Cure Diseases with Chronic Inflammations Associated with Bone Loss

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Selma Olsson Åkefeldt

2013-01-01

Full Text Available Rheumatoid arthritis (RA and Langerhans cell histiocytosis (LCH are common and rare diseases, respectively. They associate myeloid cell recruitment and survival in inflammatory conditions with tissue destruction and bone resorption. Manipulating dendritic cell (DC, and, especially, regulating their half-life and fusion, is a challenge. Indeed, these myeloid cells display pathogenic roles in both diseases and may be an important source of precursors for differentiation of osteoclasts, the bone-resorbing multinucleated giant cells. We have recently documented that the proinflammatory cytokine IL-17A regulates long-term survival of DC by inducing BCL2A1 expression, in addition to the constitutive MCL1 expression. We summarize bibliography of the BCL2 family members and their therapeutic targeting, with a special emphasis on MCL1 and BCL2A1, discussing their potential impact on RA and LCH. Our recent knowledge in the survival pathway, which is activated to perform DC fusion in the presence of IL-17A, suggests that targeting MCL1 and BCL2A1 in infiltrating DC may affect the clinical outcomes in RA and LCH. The development of new therapies, interfering with MCL1 and BCL2A1 expression, to target long-term surviving inflammatory DC should be translated into preclinical studies with the aim to increase the well-being of patients with RA and LCH.

Genomic rearrangement in radiation-induced murine myeloid leukemia

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Ishihara, Hiroshi

1994-01-01

After whole body irradiation of 3Gy X ray to C3H/He male mice, acute myeloid leukemia is induced at an incidence of 20 to 30% within 2 years. We have studied the mechanism of occurrence of this radiation-induced murine myeloid leukemia. Detection and isolation of genomic structural aberration which may be accumulated accompanied with leukemogenesis are helpful in analyzing the complicated molecular process from radiation damage to leukemogenesis. So, our research work was done in three phases. First, structures of previously characterized oncogenes and cytokine-related genes were analyzed, and abnormal structures of fms(protooncogene encoding M-CSF receptor gene)-related and myc-related genes were found in several leukemia cells. Additionally, genomic structural aberration of IL-3 gene was observed in some leukemia cells, so that construction of genomic libraries and cloning of the abnormal IL-3 genomic DNAs were performed to characterize the structure. Secondly, because the breakage of chromosome 2 that is frequently observed in myeloid leukemia locates in proximal position of IL-1 gene cluster in some cases, the copy number of IL-1 gene was determined and the gene was cloned. Lastly, the abnormal genome of leukemia cell was cloned by in-gel competence reassociation method. We discussed these findings and evaluated the analysis of the molecular process of leukemogenesis using these cloned genomic fragments. (author)

Excess circulating alternatively activated myeloid (M2 cells accelerate ALS progression while inhibiting experimental autoimmune encephalomyelitis.

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Ilan Vaknin

Full Text Available Circulating immune cells including autoreactive T cells and monocytes have been documented as key players in maintaining, protecting and repairing the central nervous system (CNS in health and disease. Here, we hypothesized that neurodegenerative diseases might be associated, similarly to tumors, with increased levels of circulating peripheral myeloid derived suppressor cells (MDSCs, representing a subset of suppressor cells that often expand under pathological conditions and inhibit possible recruitment of helper T cells needed for fighting off the disease.We tested this working hypothesis in amyotrophic lateral sclerosis (ALS and its mouse model, which are characterized by a rapid progression once clinical symptoms are evident. Adaptive transfer of alternatively activated myeloid (M2 cells, which homed to the spleen and exhibited immune suppressive activity in G93A mutant superoxide dismutase-1 (mSOD1 mice at a stage before emergence of disease symptoms, resulted in earlier appearance of disease symptoms and shorter life expectancy. The same protocol mitigated the inflammation-induced disease model of multiple sclerosis, experimental autoimmune encephalomyelitis (EAE, which requires circulating T cells for disease induction. Analysis of whole peripheral blood samples obtained from 28 patients suffering from sporadic ALS (sALS, revealed a two-fold increase in the percentage of circulating MDSCs (LIN(-/LowHLA-DR(-CD33(+ compared to controls.Taken together, these results emphasize the distinct requirements for fighting the inflammatory neurodegenerative disease, multiple sclerosis, and the neurodegenerative disease, ALS, though both share a local inflammatory component. Moreover, the increased levels of circulating MDSCs in ALS patients indicates the operation of systemic mechanisms that might lead to an impairment of T cell reactivity needed to overcome the disease conditions within the CNS. This high level of suppressive immune cells might

BAG1: the guardian of anti-apoptotic proteins in acute myeloid leukemia.

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Sanja Aveic

Full Text Available BCL2 associated Athano-Gene 1 (BAG1 is a multifunctional protein that has been described to be involved in different cell processes linked to cell survival. It has been reported as deregulated in diverse cancer types. Here, BAG1 protein was found highly expressed in children with acute myeloid leukemia at diagnosis, and in a cohort of leukemic cell lines. A silencing approach was used for determining BAG1's role in AML, finding that its down-regulation decreased expression of BCL2, BCL-XL, MCL1, and phospho-ERK1/2, all proteins able to sustain leukemia, without affecting the pro-apoptotic protein BAX. BAG1 down-regulation was also found to increase expression of BAG3, whose similar activity was able to compensate the loss of function of BAG1. BAG1/BAG3 co-silencing caused an enhanced cell predisposition to death in cell lines and also in primary AML cultures, affecting the same proteins. Cell death was CASPASE-3 dependent, was accompanied by PARP cleavage and documented by an increased release of pro-apoptotic molecules Smac/DIABLO and Cytochrome c. BAG1 was found to directly maintain BCL2 and to protect MCL1 from proteasomal degradation by controlling USP9X expression, which appeared to be its novel target. Finally, BAG1 was found able to affect leukemia cell fate by influencing the expression of anti-apoptotic proteins crucial for AML maintenance.

A novel application of furazolidone: anti-leukemic activity in acute myeloid leukemia.

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Xueqing Jiang

Full Text Available Acute myeloid leukemia (AML is the most common malignant myeloid disorder of progenitor cells in myeloid hematopoiesis and exemplifies a genetically heterogeneous disease. The patients with AML also show a heterogeneous response to therapy. Although all-trans retinoic acid (ATRA has been successfully introduced to treat acute promyelocytic leukemia (APL, it is rather ineffective in non-APL AML. In our present study, 1200 off-patent marketed drugs and natural compounds that have been approved by the Food and Drug Administration (FDA were screened for anti-leukemia activity using the retrovirus transduction/transformation assay (RTTA. Furazolidone (FZD was shown to inhibit bone marrow transformation mediated by several leukemia fusion proteins, including AML1-ETO. Furazolidone has been used in the treatment of certain bacterial and protozoan infections in human and animals for more than sixty years. We investigated the anti-leukemic activity of FZD in a series of AML cells. FZD displayed potent antiproliferative properties at submicromolar concentrations and induced apoptosis in AML cell lines. Importantly, FZD treatment of certain AML cells induced myeloid cell differentiation by morphology and flow cytometry for CD11b expression. Furthermore, FZD treatment resulted in increased stability of tumor suppressor p53 protein in AML cells. Our in vitro results suggest furazolidone as a novel therapeutic strategy in AML patients.

BCR-ABL1 tyrosine kinase inhibitors for the treatment of chronic myeloid leukemia.

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Cuellar, Sandra; Vozniak, Michael; Rhodes, Jill; Forcello, Nicholas; Olszta, Daniel

2017-01-01

The management of chronic myeloid leukemia with BCR-ABL1 tyrosine kinase inhibitors has evolved chronic myeloid leukemia into a chronic, manageable disease. A patient-centered approach is important for the appropriate management of chronic myeloid leukemia and optimization of long-term treatment outcomes. The pharmacist plays a key role in treatment selection, monitoring drug-drug interactions, identification and management of adverse events, and educating patients on adherence. The combination of tyrosine kinase inhibitors with unique safety profiles and individual patients with unique medical histories can make managing treatment difficult. This review will provide up-to-date information regarding tyrosine kinase inhibitor-based treatment of patients with chronic myeloid leukemia. Management strategies for adverse events and considerations for drug-drug interactions will not only vary among patients but also across tyrosine kinase inhibitors. Drug-drug interactions can be mild to severe. In instances where co-administration of concomitant medications cannot be avoided, it is critical to understand how drug levels are impacted and how subsequent dose modifications ensure therapeutic drug levels are maintained. An important component of patient-centered management of chronic myeloid leukemia also includes educating patients on the significance of early and regular monitoring of therapeutic milestones, emphasizing the importance of adhering to treatment in achieving these targets, and appropriately modifying treatment if these clinical goals are not being met. Overall, staying apprised of current research, utilizing the close pharmacist-patient relationship, and having regular interactions with patients, will help achieve successful long-term treatment of chronic myeloid leukemia in the age of BCR-ABL1 tyrosine kinase inhibitors.

Childhood Acute Myeloid Leukemia Treatment (PDQ®)—Patient Version

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Childhood acute myeloid leukemia and other myeloid malignancies treatment may include chemotherapy, radiation therapy, stem cell transplant, and targeted therapy. Learn more about AML and myelodysplastic/myeloproliferative diseases in this expert-reviewed summary.

Two Distinct Myeloid Subsets at the Term Human Fetal–Maternal Interface

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Maria Laura Costa

2017-10-01

Full Text Available During pregnancy, immune cells infiltrate the placenta at different stages of fetal development. NK cells and macrophages are the most predominant cell types. These immune cells play pleiotropic roles, as they control spiral artery remodeling to ensure appropriate blood supply and maintain long-term tolerance to a true allograft; yet, they must be able to mount appropriate immune defenses to pathogens that may threaten the fetus. Whether the same cell type accomplishes all these tasks or if there are dedicated subsets remains controversial. Here, we identify and characterize two distinct subsets of myeloid cells that differ in their pro-inflammatory/regulatory capacity. While one subset predominantly produces the immune-modulating cytokine IL-10, the second subset has superior capacity to secrete pro-inflammatory mediators, such as IL-1β and IL-6. The putative regulatory myeloid cells also express high levels of inhibitory receptors and their ligands, including programmed cell death 1 (PD1 ligands. Importantly, a large fraction of CD8 and CD4 cells in normal term human placenta are PD1 positive, suggesting that the PD1/PD1 ligands axis might be critical to maintain tolerance during pregnancy.

19-nor vitamin-D analogs: a new class of potent inhibitors of proliferation and inducers of differentiation of human myeloid leukemia cell lines.

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Asou, H; Koike, M; Elstner, E; Cambell, M; Le, J; Uskokovic, M R; Kamada, N; Koeffler, H P

1998-10-01

We have studied the in vitro biological activities and mechanisms of action of 1,25-dihydroxyvitamin D3 (1,25D3) and nine potent 1,25D3 analogs on proliferation and differentiation of myeloid leukemia cell lines (HL-60, retinoic acid-resistant HL-60 [RA-res HL-60], NB4 and Kasumi-1). The common novel structural motiff for almost all the analogs included removal of C-19 (19-nor); each also had unsaturation of the side chain. All the compounds were potent; for example, the concentration of analogs producing a 50% clonal inhibition (ED50) ranged between 1 x 10(-9) to 4 x 10(-11) mol/L when using the HL-60 cell line. The most active compound [1, 25(OH)2-16,23E-diene-26-trifluoro-19-nor-cholecalciferol (Ro 25-9716)] had an ED50 of 4 x 10(-11) mol/L; in contrast, the 1,25D3 produced an ED50 of 10(-9) mol/L with the HL-60 target cells. Ro 25-9716 (10(-9) mol/L, 3 days) was a strong inducer of myeloid differentiation because it caused 92% of the HL-60 cells to express CD11b and 75% of these cells to reduce nitroblue tetrazolium (NBT). This compound (10(-8) mol/L, 4 days) also caused HL-60 cells to arrest in the G1 phase of the cell cycle (88% cells in G1 v 48% of the untreated control cells). The p27(kip-1), a cyclin-dependent kinase inhibitor which is important in blocking the cell cycle, was induced more quickly and potently by Ro 25-9716 (10(-7) mol/L, 0 to 5 days) than by 1,25D3, suggesting a possible mechanism by which these analogs inhibit proliferation of leukemic growth. The NB4 promyelocytic leukemia cells cultured with the Ro 25-9716 were also inhibited in their clonal proliferation (ED50, 5 x 10(-11) mol/L) and their expression of CD11b was enhanced (80% positive [10(-9) mol/L, 4 days] v 27% untreated NB4 cells). Moreover, the combination of Ro 25-9716 (10(-9) mol/L) and all-trans retinoic acid (ATRA, 10(-7) mol/L) induced 92% of the NB4 cells to reduce NBT, whereas only 26% of the cells became NBT positive after a similar exposure to the combination of 1,25D3

Systemic T Cells Immunosuppression of Glioma Stem Cell-Derived Exosomes Is Mediated by Monocytic Myeloid-Derived Suppressor Cells.

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Rossana Domenis

Full Text Available A major contributing factor to glioma development and progression is its ability to evade the immune system. Nano-meter sized vesicles, exosomes, secreted by glioma-stem cells (GSC can act as mediators of intercellular communication to promote tumor immune escape. Here, we investigated the immunomodulatory properties of GCS-derived exosomes on different peripheral immune cell populations. Healthy donor peripheral blood mononuclear cells (PBMCs stimulated with anti-CD3, anti-CD28 and IL-2, were treated with GSC-derived exosomes. Phenotypic characterization, cell proliferation, Th1/Th2 cytokine secretion and intracellular cytokine production were analysed by distinguishing among effector T cells, regulatory T cells and monocytes. In unfractionated PBMCs, GSC-derived exosomes inhibited T cell activation (CD25 and CD69 expression, proliferation and Th1 cytokine production, and did not affect cell viability or regulatory T-cell suppression ability. Furthermore, exosomes were able to enhance proliferation of purified CD4+ T cells. In PBMCs culture, glioma-derived exosomes directly promoted IL-10 and arginase-1 production and downregulation of HLA-DR by unstimulated CD14+ monocytic cells, that displayed an immunophenotype resembling that of monocytic myeloid-derived suppressor cells (Mo-MDSCs. Importantly, the removal of CD14+ monocytic cell fraction from PBMCs restored T-cell proliferation. The same results were observed with exosomes purified from plasma of glioblastoma patients. Our results indicate that glioma-derived exosomes suppress T-cell immune response by acting on monocyte maturation rather than on direct interaction with T cells. Selective targeting of Mo-MDSC to treat glioma should be considered with regard to how immune cells allow the acquirement of effector functions and therefore counteracting tumor progression.

Signaling by myeloid C-type lectin receptors in immunity and homeostasis.

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Sancho, David; Reis e Sousa, Caetano

2012-01-01

Myeloid cells are key drivers of physiological responses to pathogen invasion or tissue damage. Members of the C-type lectin receptor (CLR) family stand out among the specialized receptors utilized by myeloid cells to orchestrate these responses. CLR ligands include carbohydrate, protein, and lipid components of both pathogens and self, which variably trigger endocytic, phagocytic, proinflammatory, or anti-inflammatory reactions. These varied outcomes rely on a versatile system for CLR signaling that includes tyrosine-based motifs that recruit kinases, phosphatases, or endocytic adaptors as well as nontyrosine-based signals that modulate the activation of other pathways or couple to the uptake machinery. Here, we review the signaling properties of myeloid CLRs and how they impact the role of myeloid cells in innate and adaptive immunity.

Peroxisome Proliferator-Activated Receptor Ligands and Their Role in Chronic Myeloid Leukemia: Therapeutic Strategies.

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Yousefi, Bahman; Samadi, Nasser; Baradaran, Behzad; Shafiei-Irannejad, Vahid; Zarghami, Nosratollah

2016-07-01

Imatinib therapy remains the gold standard for treatment of chronic myeloid leukemia; however, the acquired resistance to this therapeutic agent in patients has urged the scientists to devise modalities for overcoming this chemoresistance. For this purpose, initially therapeutic agents with higher tyrosine kinase activity were introduced, which had the potential for inhibiting even mutant forms of Bcr-Abl. Furthermore, coupling imatinib with peroxisome proliferator-activated receptor ligands also showed beneficial effects in chronic myeloid leukemia cell proliferation. These combination protocols inhibited cell growth and induced apoptosis as well as differentiation in chronic myeloid leukemia cell lines. In addition, peroxisome proliferator-activated receptors ligands increased imatinib uptake by upregulating the expression of human organic cation transporter 1. Taken together, peroxisome proliferator-activated receptors ligands are currently being considered as novel promising therapeutic candidates for chronic myeloid leukemia treatment, because they can synergistically enhance the efficacy of imatinib. In this article, we reviewed the potential of peroxisome proliferator-activated receptors ligands for use in chronic myeloid leukemia treatment. The mechanism of action of these therapeutics modalities are also presented in detail. © 2016 John Wiley & Sons A/S.

Program death-1 signaling and regulatory T cells collaborate to resist the function of adoptively transferred cytotoxic T lymphocytes in advanced acute myeloid leukemia.

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Zhou, Qing; Munger, Meghan E; Highfill, Steven L; Tolar, Jakub; Weigel, Brenda J; Riddle, Megan; Sharpe, Arlene H; Vallera, Daniel A; Azuma, Miyuki; Levine, Bruce L; June, Carl H; Murphy, William J; Munn, David H; Blazar, Bruce R

2010-10-07

Tumor-induced immune defects can weaken host immune response and permit tumor cell growth. In a systemic model of murine acute myeloid leukemia (AML), tumor progression resulted in increased regulatory T cells (Treg) and elevation of program death-1 (PD-1) expression on CD8(+) cytotoxic T cells (CTLs) at the tumor site. PD-1 knockout mice were more resistant to AML despite the presence of similar percentage of Tregs compared with wild type. In vitro, intact Treg suppression of CD8(+) T-cell responses was dependent on PD-1 expression by T cells and Tregs and PD-L1 expression by antigen-presenting cells. In vivo, the function of adoptively transferred AML-reactive CTLs was reduced by AML-associated Tregs. Anti-PD-L1 monoclonal antibody treatment increased the proliferation and function of CTLs at tumor sites, reduced AML tumor burden, and resulted in long-term survivors. Treg depletion followed by PD-1/PD-L1 blockade showed superior efficacy for eradication of established AML. These data demonstrated that interaction between PD-1 and PD-L1 can facilitate Treg-induced suppression of T-effector cells and dampen the antitumor immune response. PD-1/PD-L1 blockade coupled with Treg depletion represents an important new approach that can be readily translated into the clinic to improve the therapeutic efficacy of adoptive AML-reactive CTLs in advanced AML disease.

HA-1 T TCR T Cell Immunotherapy for the Treating of Patients With Relapsed or Refractory Acute Leukemia After Donor Stem Cell Transplant

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2018-04-30

HLA-A*0201 HA-1 Positive Cells Present; Minimal Residual Disease; Recurrent Acute Biphenotypic Leukemia; Recurrent Acute Undifferentiated Leukemia; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Acute Myeloid Leukemia; Recurrent Childhood Acute Lymphoblastic Leukemia; Recurrent Childhood Acute Myeloid Leukemia; Refractory Acute Myeloid Leukemia; Refractory Adult Acute Lymphoblastic Leukemia; Refractory Childhood Acute Lymphoblastic Leukemia

Chronic myeloid leukemia: reminiscences and dreams

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Mughal, Tariq I.; Radich, Jerald P.; Deininger, Michael W.; Apperley, Jane F.; Hughes, Timothy P.; Harrison, Christine J.; Gambacorti-Passerini, Carlo; Saglio, Giuseppe; Cortes, Jorge; Daley, George Q.

2016-01-01

With the deaths of Janet Rowley and John Goldman in December 2013, the world lost two pioneers in the field of chronic myeloid leukemia. In 1973, Janet Rowley, unraveled the cytogenetic anatomy of the Philadelphia chromosome, which subsequently led to the identification of the BCR-ABL1 fusion gene and its principal pathogenetic role in the development of chronic myeloid leukemia. This work was also of major importance to support the idea that cytogenetic changes were drivers of leukemogenesis. John Goldman originally made seminal contributions to the use of autologous and allogeneic stem cell transplantation from the late 1970s onwards. Then, in collaboration with Brian Druker, he led efforts to develop ABL1 tyrosine kinase inhibitors for the treatment of patients with chronic myeloid leukemia in the late 1990s. He also led the global efforts to develop and harmonize methodology for molecular monitoring, and was an indefatigable organizer of international conferences. These conferences brought together clinicians and scientists, and accelerated the adoption of new therapies. The abundance of praise, tributes and testimonies expressed by many serve to illustrate the indelible impressions these two passionate and affable scholars made on so many people’s lives. This tribute provides an outline of the remarkable story of chronic myeloid leukemia, and in writing it, it is clear that the historical triumph of biomedical science over this leukemia cannot be considered without appreciating the work of both Janet Rowley and John Goldman. PMID:27132280

Post-transplant outcome in chronic myeloid leukemia

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Raza, S.; Ullah, K.; Ahmed, P.; Kamal, M.K.

2008-01-01

To determine post-transplant survival in chronic myeloid leukaemia patients undergoing allogeneic stem cell transplant. All patients of chronic myeloid leukaemia in chronic phase having HLA identical donor and age under 55 years, normal hepatic, renal and cardiac functions with good performance status were selected. Patients in accelerated phase or blast crisis, poor performance status, impaired hepatic, renal, cardiac functions or pregnancy were excluded. Survival was calculated from the date of transplant to death or last follow-up according to Kaplan-Meier and Cox (proportional hazard) regression analysis methods. Thirty seven patients with chronic myeloid leukaemia underwent allogeneic stem cell transplant from HLA identical sibling donors. Thirty two patients were male and five were females. Median age of patients was 28 years. All patients and donors were CMV positive. Post-transplant complications encountered were acute GvHD (Grade II-IV) (n=13, 35.1%), chronic GvHD in 18.9% (n=7), Veno Occlusive Disease (VOD) in 5.4% (n=2), acute renal failure in 2.7% (n=1), haemorrhagic cystitis in 2.7% (n=1), bacterial infections in 40.5% (n=15), fungal infections in 16.2% (n=6), CMV infection in 5.4% (n=2), tuberculosis in 5.4% (n=2), Herpes Zoster infection 2.7% (n=1) and relapse in 2.7% (n=1). Mortality was observed in 27% (n=10). Major causes of mortality were GvHD, VOD, septicemia, CMV infection and disseminated Aspergillosis. Overall Disease Free Survival (DFS) was 73% with a median duration of follow-up of 47.4 + 12 months. DFS was 81% in standard risk and 54.5% in high-risk group. Results of allogeneic stem cell transplant in standard risk group CML patients were good and comparable with other international centres, however, results in high-risk CML patients need further improvement, although, number of patients in this group is small. (author)

In vivo expansion of co-transplanted T cells impacts on tumor re-initiating activity of human acute myeloid leukemia in NSG mice.

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Malte von Bonin

Full Text Available Human cells from acute myeloid leukemia (AML patients are frequently transplanted into immune-compromised mouse strains to provide an in vivo environment for studies on the biology of the disease. Since frequencies of leukemia re-initiating cells are low and a unique cell surface phenotype that includes all tumor re-initiating activity remains unknown, the underlying mechanisms leading to limitations in the xenotransplantation assay need to be understood and overcome to obtain robust engraftment of AML-containing samples. We report here that in the NSG xenotransplantation assay, the large majority of mononucleated cells from patients with AML fail to establish a reproducible myeloid engraftment despite high donor chimerism. Instead, donor-derived cells mainly consist of polyclonal disease-unrelated expanded co-transplanted human T lymphocytes that induce xenogeneic graft versus host disease and mask the engraftment of human AML in mice. Engraftment of mainly myeloid cell types can be enforced by the prevention of T cell expansion through the depletion of lymphocytes from the graft prior transplantation.

Protein tyrosine phosphatase 1B deficiency ameliorates murine experimental colitis via the expansion of myeloid-derived suppressor cells.

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Jing Zhang

Full Text Available Protein tyrosine phosphatase 1B (PTP1B is a key molecule in modulating low-degree inflammatory conditions such as diabetes. The role of PTP1B in other chronic inflammations, however, remains unknown. Here, we report that PTP1B deficiency ameliorates Dextran Sulfate Sodium (DSS-induced murine experimental colitis via expanding CD11b(+Gr-1(+ myeloid-derived suppressor cells (MDSCs. Employing DSS-induced murine experimental colitis as inflammatory animal model, we found that, compared with wild-type littermates, PTP1B-null mice demonstrated greater resistance to DSS-induced colitis, as reflected by slower weight-loss, greater survival rates and decreased PMN and macrophage infiltration into the colon. The evidence collectively also demonstrated that the resistance of PTP1B-null mice to DSS-induced colitis is based on the expansion of MDSCs. First, PTP1B-null mice exhibited a greater frequency of MDSCs in the bone marrow (BM, peripheral blood and spleen when compared with wild-type littermates. Second, PTP1B levels in BM leukocytes were significantly decreased after cells were induced into MDSCs by IL-6 and GM-CSF, and the MDSC induction occurred more rapidly in PTP1B-null mice than in wild-type littermates, suggesting PTP1B as a negative regulator of MDSCs. Third, the adoptive transfer of MDSCs into mice with DSS-colitis significantly attenuated colitis, which accompanies with a decreased serum IL-17 level. Finally, PTP1B deficiency increased the frequency of MDSCs from BM cells likely through enhancing the activities of signal transducer and activator of transcription 3 (STAT3 and Janus kinase 2 (JAK2. In conclusion, our study provides the first evidences that PTP1B deficiency ameliorates murine experimental colitis via expanding MDSCs.

Pathologic and Protective Roles for Microglial Subsets and Bone Marrow- and Blood-Derived Myeloid Cells in Central Nervous System Inflammation

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Wlodarczyk, Agnieszka; Cédile, Oriane; Jensen, Kirstine Nolling

2015-01-01

Inflammation is a series of processes designed for eventual clearance of pathogens and repair of damaged tissue. In the context of autoimmune recognition, inflammatory processes are usually considered to be pathological. This is also true for inflammatory responses in the central nervous system...... (CNS). However, as in other tissues, neuroinflammation can have beneficial as well as pathological outcomes. The complex role of encephalitogenic T cells in multiple sclerosis and its animal model experimental autoimmune encephalomyelitis (EAE) may derive from heterogeneity of the myeloid cells...... with which these T cells interact within the CNS. Myeloid cells, including resident microglia and infiltrating bone marrow-derived cells, such as dendritic cells (DC) and monocytes/macrophages [bone marrow-derived macrophages (BMDM)], are highly heterogeneous populations that may be involved in neurotoxicity...

Cutaneous myeloid sarcoma: natural history and biology of an uncommon manifestation of acute myeloid leukemia.

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Hurley, M Yadira; Ghahramani, Grant K; Frisch, Stephanie; Armbrecht, Eric S; Lind, Anne C; Nguyen, Tudung T; Hassan, Anjum; Kreisel, Friederike H; Frater, John L

2013-05-01

We conducted a retrospective study of patients with cutaneous myeloid sarcoma, from 2 tertiary care institutions. Eighty-three patients presented, with a mean age of 52 years. Diagnosis of myeloid sarcoma in the skin was difficult due to the low frequency of myeloperoxidase and/or CD34+ cases (56% and 19% of tested cases, respectively). Seventy-one of the 83 patients (86%) had ≥ 1 bone marrow biopsy. Twenty-eight (39%) had acute myeloid leukemia with monocytic differentiation. Twenty-three had other de novo acute myeloid leukemia subtypes. Thirteen patients had other myeloid neoplasms, of which 4 ultimately progressed to an acute myeloid leukemia. Seven had no bone marrow malignancy. Ninety-eight percent of the patients received chemotherapy, and approximately 89% died of causes related to their disease. Cutaneous myeloid sarcoma in most cases represents an aggressive manifestation of acute myeloid leukemia. Diagnosis can be challenging due to lack of myeloblast-associated antigen expression in many cases, and difficulty in distinguishing monocyte-lineage blasts from neoplastic and non-neoplastic mature monocytes.

Aberrant DNA Methylation in Chronic Myeloid Leukemia: Cell Fate Control, Prognosis, and Therapeutic Response.

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Behzad, Masumeh Maleki; Shahrabi, Saeid; Jaseb, Kaveh; Bertacchini, Jessika; Ketabchi, Neda; Saki, Najmaldin

2018-01-31

Chronic myeloid leukemia (CML) is a hematopoietic stem cell malignancy characterized by the expression of the BCR-ABL1 fusion gene with different chimeric transcripts. Despite the crucial impact of constitutively active tyrosine kinase in CML pathogenesis, aberrant DNA methylation of certain genes plays an important role in disease progression and the development of drug resistance. This article reviews recent findings relevant to the effect of DNA methylation pattern of regulatory genes on various cellular activities such as cell proliferation and survival, as well as cell-signaling molecules in CML. These data might contribute to defining the role of aberrant DNA methylation in disease initiation and progression. However, further studies are needed on the validation of specific aberrant methylation markers regarding the prognosis and prediction of response among the CML patients.

Specific Inhibition of the VEGFR-3 Tyrosine Kinase by SAR131675 Reduces Peripheral and Tumor Associated Immunosuppressive Myeloid Cells

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Espagnolle, Nicolas; Barron, Pauline; Mandron, Marie; Blanc, Isabelle; Bonnin, Jacques; Agnel, Magali; Kerbelec, Erwan; Herault, Jean Pascal; Savi, Pierre; Bono, Françoise; Alam, Antoine

2014-01-01

Myeloid derived suppressor cells (MDSCs) and tumor-associated macrophages (TAMs) represent prominent components in cancer progression. We previously showed that inhibition of the VEGFR-3 pathway by SAR131675 leads to reduction of TAM infiltration and tumor growth. Here, we found that treatment with SAR131675 prevents the accumulation of immunosuppressive blood and splenic MDSCs which express VEGFR-3, in 4T1 tumor bearing mice. Moreover we showed that soluble factors secreted by tumor cells promote MDSCs proliferation and differentiation into M2 polarized F4/80+ macrophages. In addition, cell sorting and transcriptomic analysis of tumor infiltrating myeloid cells revealed the presence of a heterogeneous population that could be divided into 3 subpopulations: (i) immature cells with a MDSC phenotype (GR1+/CD11b+/F4/80 − ); (ii) “immuno-incompetent” macrophages (F4/80 high /CD86 neg /MHCII Low ) strongly expressing M2 markers such as Legumain, CD206 and Mgl1/2 and (iii) “immuno-competent”-M1 like macrophages (F4/80 Low /CD86 + /MHCII High ). SAR131675 treatment reduced MDSCs in lymphoid organs as well as F4/80 High populations in tumors. Interestingly, in the tumor SAR131675 was able to increase the immunocompetent M1 like population (F4/80 low ). Altogether these results demonstrate that the specific VEGFR-3 inhibitor SAR131675 exerts its anti tumoral activity by acting on different players that orchestrate immunosuppression and cancer progression in a tumoral context: MDSCs in peripheral lymphoid organs and TAMs infiltrating the tumor

T315 Decreases Acute Myeloid Leukemia Cell Viability through a Combination of Apoptosis Induction and Autophagic Cell Death

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Chang-Fang Chiu

2016-08-01

Full Text Available T315, an integrin-linked kinase (ILK inhibitor, has been shown to suppress the proliferation of breast cancer, stomach cancer and chronic lymphocytic leukemia cells. Here we demonstrate that T315 decreases cell viability of acute myeloid leukemia (AML cell lines (HL-60 and THP-1 and primary leukemia cells from AML patients in a dose-responsive manner. Normal human bone marrow cells are less sensitive than leukemia cells to T315. T315 down regulates protein kinase B (Akt and p-Akt and induces caspase activation, poly-ADP-ribose polymerase (PARP cleavage, apoptosis and autophagy through an ILK-independent manner. Interestingly, pretreatment with autophagy inhibitors rescues cells from apoptosis and concomitant PARP cleavage, which implicates a key role of autophagic cell death in T315-mediated cytotoxicity. T315 also demonstrates efficacy in vivo, suppressing the growth of THP-1 xenograft tumors in athymic nude mice when administered intraperitoneally. This study shows that autophagic cell death and apoptosis cooperatively contribute to the anticancer activity of T315 in AML cells. In conclusion, the complementary roles of apoptotic and autophagic cell death should be considered in the future assessment of the translational value of T315 in AML therapy.

Biology and relevance of human acute myeloid leukemia stem cells.

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Thomas, Daniel; Majeti, Ravindra

2017-03-23

Evidence of human acute myeloid leukemia stem cells (AML LSCs) was first reported nearly 2 decades ago through the identification of rare subpopulations of engrafting cells in xenotransplantation assays. These AML LSCs were shown to reside at the apex of a cellular hierarchy that initiates and maintains the disease, exhibiting properties of self-renewal, cell cycle quiescence, and chemoresistance. This cancer stem cell model offers an explanation for chemotherapy resistance and disease relapse and implies that approaches to treatment must eradicate LSCs for cure. More recently, a number of studies have both refined and expanded our understanding of LSCs and intrapatient heterogeneity in AML using improved xenotransplant models, genome-scale analyses, and experimental manipulation of primary patient cells. Here, we review these studies with a focus on the immunophenotype, biological properties, epigenetics, genetics, and clinical associations of human AML LSCs and discuss critical questions that need to be addressed in future research. © 2017 by The American Society of Hematology.

Maesopsin 4-O-beta-D-glucoside, a natural compound isolated from the leaves of Artocarpus tonkinensis, inhibits proliferation and up-regulates HMOX1, SRXN1 and BCAS3 in acute myeloid leukemia.

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Pozzesi, N; Pierangeli, S; Vacca, C; Falchi, L; Pettorossi, V; Martelli, M P; Thuy, T T; Ninh, P T; Liberati, A M; Riccardi, C; Sung, T V; Delfino, D V

2011-06-01

The leaves of Artocarpus tonkinensis are used in Vietnamese traditional medicine for treatment of arthritis, and the compound maesopsin 4-O-β-D-glucoside (TAT-2), isolated from them, inhibits the proliferation of activated T cells. Our goal was to test the anti-proliferative activity of TAT-2 on the T-cell leukemia, Jurkat, and on the acute myeloid leukemia, OCI-AML. TAT-2 inhibited the growth of OCI-AML (and additional acute myeloid leukemia cells) but not Jurkat cells. Growth inhibition was shown to be due to inhibition of proliferation rather than increase in cell death. Analysis of cytokine release showed that TAT-2 stimulated the release of TGF-β, yet TGF-β neutralization did not reverse the maesopsin-dependent effect. Gene expression profiling determined that maesopsin modulated 19 identifiable genes. Transcription factor CP2 was the gene most significantly modulated. Real-time PCR validated that up-regulation of sulphiredoxin 1 homolog (SRXN1), hemeoxygenase 1 (HMOX1), and breast carcinoma amplified sequence 3 (BCAS3) were consistently modulated.

Deficiency of leptin receptor in myeloid cells disrupts hypothalamic metabolic circuits and causes body weight increase

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Yuanqing Gao

2018-01-01

Conclusions: Myeloid cell leptin receptor deficient mice partially replicate the db/db phenotype. Leptin signaling in hypothalamic microglia is important for microglial function and a correct formation of the hypothalamic neuronal circuit regulating metabolism.

Cancer progression by reprogrammed BCAA metabolism in myeloid leukaemia.

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Hattori, Ayuna; Tsunoda, Makoto; Konuma, Takaaki; Kobayashi, Masayuki; Nagy, Tamas; Glushka, John; Tayyari, Fariba; McSkimming, Daniel; Kannan, Natarajan; Tojo, Arinobu; Edison, Arthur S; Ito, Takahiro

2017-05-25

Reprogrammed cellular metabolism is a common characteristic observed in various cancers. However, whether metabolic changes directly regulate cancer development and progression remains poorly understood. Here we show that BCAT1, a cytosolic aminotransferase for branched-chain amino acids (BCAAs), is aberrantly activated and functionally required for chronic myeloid leukaemia (CML) in humans and in mouse models of CML. BCAT1 is upregulated during progression of CML and promotes BCAA production in leukaemia cells by aminating the branched-chain keto acids. Blocking BCAT1 gene expression or enzymatic activity induces cellular differentiation and impairs the propagation of blast crisis CML both in vitro and in vivo. Stable-isotope tracer experiments combined with nuclear magnetic resonance-based metabolic analysis demonstrate the intracellular production of BCAAs by BCAT1. Direct supplementation with BCAAs ameliorates the defects caused by BCAT1 knockdown, indicating that BCAT1 exerts its oncogenic function through BCAA production in blast crisis CML cells. Importantly, BCAT1 expression not only is activated in human blast crisis CML and de novo acute myeloid leukaemia, but also predicts disease outcome in patients. As an upstream regulator of BCAT1 expression, we identified Musashi2 (MSI2), an oncogenic RNA binding protein that is required for blast crisis CML. MSI2 is physically associated with the BCAT1 transcript and positively regulates its protein expression in leukaemia. Taken together, this work reveals that altered BCAA metabolism activated through the MSI2-BCAT1 axis drives cancer progression in myeloid leukaemia.

SAMHD1 controls cell cycle status, apoptosis and HIV-1 infection in monocytic THP-1 cells

International Nuclear Information System (INIS)

Bonifati, Serena; Daly, Michele B.; St Gelais, Corine; Kim, Sun Hee; Hollenbaugh, Joseph A.; Shepard, Caitlin; Kennedy, Edward M.; Kim, Dong-Hyun; Schinazi, Raymond F.; Kim, Baek; Wu, Li

2016-01-01

SAMHD1 limits HIV-1 infection in non-dividing myeloid cells by decreasing intracellular dNTP pools. HIV-1 restriction by SAMHD1 in these cells likely prevents activation of antiviral immune responses and modulates viral pathogenesis, thus highlighting a critical role of SAMHD1 in HIV-1 physiopathology. Here, we explored the function of SAMHD1 in regulating cell proliferation, cell cycle progression and apoptosis in monocytic THP-1 cells. Using the CRISPR/Cas9 technology, we generated THP-1 cells with stable SAMHD1 knockout. We found that silencing of SAMHD1 in cycling cells stimulates cell proliferation, redistributes cell cycle population in the G_1/G_0 phase and reduces apoptosis. These alterations correlated with increased dNTP levels and more efficient HIV-1 infection in dividing SAMHD1 knockout cells relative to control. Our results suggest that SAMHD1, through its dNTPase activity, affects cell proliferation, cell cycle distribution and apoptosis, and emphasize a key role of SAMHD1 in the interplay between cell cycle regulation and HIV-1 infection.

SAMHD1 controls cell cycle status, apoptosis and HIV-1 infection in monocytic THP-1 cells

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Bonifati, Serena [Center for Retrovirus Research, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH (United States); Daly, Michele B. [Center for Drug Discovery, Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA (United States); St Gelais, Corine; Kim, Sun Hee [Center for Retrovirus Research, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH (United States); Hollenbaugh, Joseph A.; Shepard, Caitlin [Center for Drug Discovery, Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA (United States); Kennedy, Edward M. [Department of Molecular Genetics and Microbiology, Duke University, Durham, NC (United States); Kim, Dong-Hyun [Department of Pharmacy, School of Pharmacy, Kyung-Hee University, Seoul (Korea, Republic of); Schinazi, Raymond F. [Center for Drug Discovery, Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA (United States); Kim, Baek, E-mail: baek.kim@emory.edu [Center for Drug Discovery, Department of Pediatrics, School of Medicine, Emory University, Atlanta, GA (United States); Department of Pharmacy, School of Pharmacy, Kyung-Hee University, Seoul (Korea, Republic of); Wu, Li, E-mail: wu.840@osu.edu [Center for Retrovirus Research, Department of Veterinary Biosciences, The Ohio State University, Columbus, OH (United States)

2016-08-15

SAMHD1 limits HIV-1 infection in non-dividing myeloid cells by decreasing intracellular dNTP pools. HIV-1 restriction by SAMHD1 in these cells likely prevents activation of antiviral immune responses and modulates viral pathogenesis, thus highlighting a critical role of SAMHD1 in HIV-1 physiopathology. Here, we explored the function of SAMHD1 in regulating cell proliferation, cell cycle progression and apoptosis in monocytic THP-1 cells. Using the CRISPR/Cas9 technology, we generated THP-1 cells with stable SAMHD1 knockout. We found that silencing of SAMHD1 in cycling cells stimulates cell proliferation, redistributes cell cycle population in the G{sub 1}/G{sub 0} phase and reduces apoptosis. These alterations correlated with increased dNTP levels and more efficient HIV-1 infection in dividing SAMHD1 knockout cells relative to control. Our results suggest that SAMHD1, through its dNTPase activity, affects cell proliferation, cell cycle distribution and apoptosis, and emphasize a key role of SAMHD1 in the interplay between cell cycle regulation and HIV-1 infection.

EM23, a natural sesquiterpene lactone from Elephantopus mollis H.B.K., induces apoptosis in human myeloid leukemia cells through thioredoxin- and reactive oxygen species-mediated signaling pathways

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Hongyu eLi

2016-03-01

Full Text Available Elephantopus mollis H.B.K. (EM is a traditional herbal medicine with multiple pharmacological activities. However, the efficacy of EM in treating human leukemia is currently unknown. In the current study, we report that EM23, a natural sesquiterpene lactone isolated from EM, inhibits the proliferation of human chronic myeloid leukemia K562 cells and acute myeloid leukemia HL-60 cells by inducing apoptosis. Translocation of membrane-associated phospholipid phosphatidylserines, changes in cell morphology, activation of caspases and cleavage of PARP were concomitant with this inhibition. The involvement of the mitochondrial pathway in EM23-mediated apoptosis was suggested by observed disruptions in mitochondrial membrane potential (MMP. Mechanistic studies indicated that EM23 caused a marked increase in the level of reactive oxygen species (ROS. Pretreatment with N-acetyl-L-cysteine (NAC, a ROS scavenger, almost fully reversed EM23-mediated apoptosis. In EM23-treated cells, the expression levels of thioredoxin (Trx and thioredoxinreductase (TrxR, two components of the Trx system involved in maintaining cellular redox homeostasis, were significantly down-regulated. Concomitantly, Trx regulated the activation of apoptosis signal-regulating kinase 1 (ASK1 and its downstream regulatory targets, the p38, JNK, and ERK MAPKs. EM23-mediated activation of ASK1/MAPKs was significantly inhibited in the presence of NAC. Furthermore, tumor necrosis factor alpha (TNF-α-mediated activation of nuclear factor-κB (NF-κB was suppressed by EM23, as suggested by the observed blockage of p65 nuclear translocation, phosphorylation and reversion of IκBα degradation following EM23 treatment. Taken together, these results provide important insights into the anticancer activities of the EM component EM23 against human chronic myeloid leukemia K562 cells and acute myeloid leukemia HL-60 cells.

mTOR up-regulation of PFKFB3 is essential for acute myeloid leukemia cell survival

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Feng, Yonghuai; Wu, Liusong

2017-01-01

Although mTOR (mammalian target of rapamycin) activation is frequently observed in acute myeloid leukemia (AML) patients, the precise function and the downstream targets of mTOR are poorly understood. Here we revealed that PFKFB3, but not PFKFB1, PFKFB2 nor PFKFB4 was a novel downstream substrate of mTOR signaling pathway as PFKFB3 level was augmented after knocking down TSC2 in THP1 and OCI-AML3 cells. Importantly, PFKFB3 silencing suppressed glycolysis and cell proliferation of TSC2 silencing OCI-AML3 cells and activated apoptosis pathway. These results suggested that mTOR up-regulation of PFKFB3 was essential for AML cells survival. Mechanistically, Rapamycin treatment or Raptor knockdown reduced the expression of PFKFB3 in TSC2 knockdown cells, while Rictor silencing did not have such effect. Furthermore, we also revealed that mTORC1 up-regulated PFKFB3 was dependent on hypoxia-inducible factor 1α (HIF1α), a positive regulator of glycolysis. Moreover, PFKFB3 inhibitor PFK15 and rapamycin synergistically blunted the AML cell proliferation. Taken together, PFKFB3 was a promising drug target in AML patients harboring mTOR hyper-activation.

Myeloid Dysregulation in a Human Induced Pluripotent Stem Cell Model of PTPN11-Associated Juvenile Myelomonocytic Leukemia

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Sonia Mulero-Navarro

2015-10-01

Full Text Available Somatic PTPN11 mutations cause juvenile myelomonocytic leukemia (JMML. Germline PTPN11 defects cause Noonan syndrome (NS, and specific inherited mutations cause NS/JMML. Here, we report that hematopoietic cells differentiated from human induced pluripotent stem cells (hiPSCs harboring NS/JMML-causing PTPN11 mutations recapitulated JMML features. hiPSC-derived NS/JMML myeloid cells exhibited increased signaling through STAT5 and upregulation of miR-223 and miR-15a. Similarly, miR-223 and miR-15a were upregulated in 11/19 JMML bone marrow mononuclear cells harboring PTPN11 mutations, but not those without PTPN11 defects. Reducing miR-223’s function in NS/JMML hiPSCs normalized myelogenesis. MicroRNA target gene expression levels were reduced in hiPSC-derived myeloid cells as well as in JMML cells with PTPN11 mutations. Thus, studying an inherited human cancer syndrome with hiPSCs illuminated early oncogenesis prior to the accumulation of secondary genomic alterations, enabling us to discover microRNA dysregulation, establishing a genotype-phenotype association for JMML and providing therapeutic targets.

Zebrafish as a Model for the Study of Human Myeloid Malignancies

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Jeng-Wei Lu

2015-01-01

Full Text Available Myeloid malignancies are heterogeneous disorders characterized by uncontrolled proliferation or/and blockage of differentiation of myeloid progenitor cells. Although a substantial number of gene alterations have been identified, the mechanism by which these abnormalities interact has yet to be elucidated. Over the past decades, zebrafish have become an important model organism, especially in biomedical research. Several zebrafish models have been developed to recapitulate the characteristics of specific myeloid malignancies that provide novel insight into the pathogenesis of these diseases and allow the evaluation of novel small molecule drugs. This report will focus on illustrative examples of applications of zebrafish models, including transgenesis, zebrafish xenograft models, and cell transplantation approaches, to the study of human myeloid malignancies.

Camptothecin and khat (Catha edulis Forsk. induced distinct cell death phenotypes involving modulation of c-FLIPL, Mcl-1, procaspase-8 and mitochondrial function in acute myeloid leukemia cell lines

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Fossan Kjell O

2009-11-01

Full Text Available Abstract Background An organic extract of the recreational herb khat (Catha edulis Forsk. triggers cell death in various leukemia cell lines in vitro. The chemotherapeutics camptothecin, a plant alkaloid topoisomerase I inhibitor, was tested side-by-side with khat in a panel of acute myeloid leukemia cell lines to elucidate mechanisms of toxicity. Results Khat had a profound effect on MOLM-13 cells inducing mitochondrial damage, chromatin margination and morphological features of autophagy. The effects of khat on mitochondrial ultrastructure in MOLM-13 correlated with strongly impaired routine respiration, an effect neither found in the khat-resistant MV-4-11 cells nor in camptothecin treated cells. Enforced expression of anti-apoptotic Bcl-2 protein provided protection against camptothecin-induced cell death and partly against khat toxicity. Khat-induced cell death in MOLM-13 cells included reduced levels of anti-apoptotic Mcl-1 protein, while both khat and camptothecin induced c-FLIPL cleavage and procaspase-8 activation. Conclusion Khat activated a distinct cell death pathway in sensitive leukemic cells as compared to camptothecin, involving mitochondrial damage and morphological features of autophagy. This suggests that khat should be further explored in the search for novel experimental therapeutics.

Low CLL-1 Expression Is a Novel Adverse Predictor in 123 Patients with De Novo CD34+ Acute Myeloid Leukemia.

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Wang, Yan-Yu; Chen, Wen-Lian; Weng, Xiang-Qin; Sheng, Yan; Wu, Jing; Hao, Jie; Liu, Zhan-Yun; Zhu, Yong-Mei; Chen, Bing; Xiong, Shu-Min; Chen, Yu; Chen, Qiu-Sheng; Sun, Hui-Ping; Li, Jun-Min; Wang, Jin

2017-10-15

Recent reports state that C-type lectin-like molecule-1 (CLL-1) in acute myeloid leukemia (AML) is expressed primarily on myeloid cells, but there is still no investigation about its prognostic significance on leukemic blast compartment. Hence, this study aimed to evaluate the prognostic value of CLL-1 in 123 patients with de novo CD34 + Non-M3 AML. Multiparameter flow cytometry was used to assess the expression of CLL-1 on immature compartment in AML and control groups. We found that CLL-1 expression level on blast compartment was closely linked to clinical characteristics, treatment response, and survival outcome of patients. Decreased expression of CLL-1 was observed on immature compartment from AML patients as compared with controls (62.6% vs. 86.5%, P CLL-1 low independently predicted low complete remission rate with an odds ratio of 4.57 (2.53-6.61, P CLL-1 expression level at diagnosis was inversely correlated to the residual blast cells (residual leukemia cell) after induction chemotherapy (r = -0.423, P CLL-1 low was still an independent adverse predictor (P CLL-1 low was able to discriminate poor survival patients from intermediate- and favorable-risk groups. Taken together, CLL-1 is a novel prognostic predictor that could be exploited to supplement the current AML prognostic risk stratification system, and potentially optimize the clinical management of AML.

Myeloid-derived suppressor activity is mediated by monocytic lineages maintained by continuous inhibition of extrinsic and intrinsic death pathways.

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Haverkamp, Jessica M; Smith, Amber M; Weinlich, Ricardo; Dillon, Christopher P; Qualls, Joseph E; Neale, Geoffrey; Koss, Brian; Kim, Young; Bronte, Vincenzo; Herold, Marco J; Green, Douglas R; Opferman, Joseph T; Murray, Peter J

2014-12-18

Nonresolving inflammation expands a heterogeneous population of myeloid suppressor cells capable of inhibiting T cell function. This heterogeneity has confounded the functional dissection of individual myeloid subpopulations and presents an obstacle for antitumor immunity and immunotherapy. Using genetic manipulation of cell death pathways, we found the monocytic suppressor-cell subset, but not the granulocytic subset, requires continuous c-FLIP expression to prevent caspase-8-dependent, RIPK3-independent cell death. Development of the granulocyte subset requires MCL-1-mediated control of the intrinsic mitochondrial death pathway. Monocytic suppressors tolerate the absence of MCL-1 provided cytokines increase expression of the MCL-1-related protein A1. Monocytic suppressors mediate T cell suppression, whereas their granulocytic counterparts lack suppressive function. The loss of the granulocytic subset via conditional MCL-1 deletion did not alter tumor incidence implicating the monocytic compartment as the functionally immunosuppressive subset in vivo. Thus, death pathway modulation defines the development, survival, and function of myeloid suppressor cells. Copyright © 2014 Elsevier Inc. All rights reserved.

Long non-coding RNA taurine-upregulated gene 1 correlates with poor prognosis, induces cell proliferation, and represses cell apoptosis via targeting aurora kinase A in adult acute myeloid leukemia.

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Wang, Xinfeng; Zhang, Lina; Zhao, Fan; Xu, Ruirong; Jiang, Jie; Zhang, Chenglu; Liu, Hong; Huang, Hongming

2018-04-13

This study aimed to investigate the correlation of long non-coding RNA (lncRNA) taurine-upregulated gene 1 (TUG1) with clinicopathological feature and prognosis, and to explore its effect on cell proliferation and apoptosis as well as the relevant target genes in adult acute myeloid leukemia (AML). LncRNA TUG1 expression was detected in bone marrow samples from 186 AML patients and 62 controls. Blank mimic, lncRNA TUG1 mimic, blank inhibitor, and lncRNA TUG1 inhibitor lentivirus vectors were transfected in KG-1 cells. Rescue experiment was performed by transfection of lncRNA TUG1 inhibitor and aurora kinase A (AURKA) mimic lentivirus vectors. Cell proliferation, apoptosis, RNA, and protein expressions were determined by CKK-8, annexin V-FITC-propidium iodide, quantitative polymerase chain reaction, and western blot assays. LncRNA TUG1 expression was higher in AML patients compared to controls and correlated with higher white blood cell counts, monosomal karyotype, FLT3-ITD mutation, poor-risk stratification, and poor prognosis, which independently predicted worse event-free survival and overall survival. In vitro, lncRNA TUG1 expression was higher in AML cell lines (KG-1, MOLM-14, HL-60, NB-4, and THP-1 cells) compared to controls. LncRNA TUG1 mimic promoted cell proliferation and decreased cell apoptosis rate, while lncRNA TUG1 inhibitor repressed cell proliferation and increased cell apoptosis rate. Rescue experiment showed that AURKA attenuated the influence of lncRNA TUG1 on AML cell proliferation and apoptosis. In conclusion, lncRNA TUG1 associates with advanced disease and worse prognosis in adult AML patients, and it induces AML cell proliferation and represses cell apoptosis via targeting AURKA.

Adverse fibrosis in the aging heart depends on signaling between myeloid and mesenchymal cells; role of inflammatory fibroblasts.

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Cieslik, Katarzyna A; Trial, JoAnn; Crawford, Jeffrey R; Taffet, George E; Entman, Mark L

2014-05-01

Aging has been associated with adverse fibrosis. Here we formulate a new hypothesis and present new evidence that unresponsiveness of mesenchymal stem cells (MSC) and fibroblasts to transforming growth factor beta (TGF-β), due to reduced expression of TGF-β receptor I (TβRI), provides a foundation for cardiac fibrosis in the aging heart via two mechanisms. 1) TGF-β promotes expression of Nanog, a transcription factor that retains MSC in a primitive state. In MSC derived from the aging heart, Nanog expression is reduced and therefore MSC gradually differentiate and the number of mesenchymal fibroblasts expressing collagen increases. 2) As TGF-β signaling pathway components negatively regulate transcription of monocyte chemoattractant protein-1 (MCP-1), a reduced expression of TβRI prevents aging mesenchymal cells from shutting down their own MCP-1 expression. Elevated MCP-1 levels that originated from MSC attract transendothelial migration of mononuclear leukocytes from blood to the tissue. MCP-1 expressed by mesenchymal fibroblasts promotes further migration of monocytes and T lymphocytes away from the endothelial barrier and supports the monocyte transition into macrophages and finally into myeloid fibroblasts. Both myeloid and mesenchymal fibroblasts contribute to fibrosis in the aging heart via collagen synthesis. This article is part of a Special Issue entitled "Myocyte-Fibroblast Signalling in Myocardium ". © 2013. Published by Elsevier Ltd. All rights reserved.

Anticancer activity of Pupalia lappacea on chronic myeloid leukemia K562 cells.

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Ravi, Alvala; Alvala, Mallika; Sama, Venkatesh; Kalle, Arunasree M; Irlapati, Vamshi K; Reddy, B Madhava

2012-12-05

Cancer is one of the most prominent human diseases which has enthused scientific and commercial interest in the discovery of newer anticancer agents from natural sources. Here we demonstrated the anticancer activity of ethanolic extract of aerial parts of Pupalia lappacea (L) Juss (Amaranthaceae) (EAPL) on Chronic Myeloid Leukemia K562 cells. Antiproliferative activity of EAPL was determined by MTT assay using carvacrol as a positive control. Induction of apoptosis was studied by annexin V, mitochondrial membrane potential, caspase activation and cell cycle analysis using flow cytometer and modulation in protein levels of p53, PCNA, Bax and Bcl2 ratio, cytochrome c and cleavage of PARP were studied by Western blot analysis. The standardization of the extract was performed through reverse phase-HPLC using Rutin as biomarker. The results showed dose dependent decrease in growth of K562 cells with an IC50 of 40 ± 0.01 μg/ml by EAPL. Induction of apoptosis by EAPL was dose dependent with the activation of p53, inhibition of PCNA, decrease in Bcl2/Bax ratio, decrease in the mitochondrial membrane potential resulting in release of cytochrome c, activation of multicaspase and cleavage of PARP. Further HPLC standardization of EAPL showed presence 0.024% of Rutin. Present study significantly demonstrates anticancer activity of EAPL on Chronic Myeloid Leukemia (K562) cells which can lead to potential therapeutic agent in treating cancer. Rutin, a known anti cancer compound is being reported and quantified for the first time from EAPL.

Cytomegalovirus reactivation is associated with a lower rate of early relapse in myeloid malignancies independent of in-vivo T cell depletion strategy.

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Hilal, Talal; Slone, Stacey; Peterson, Shawn; Bodine, Charles; Gul, Zartash

2017-06-01

The association between cytomegalovirus (CMV) reactivation and relapse risk has not been evaluated in relation to T cell depletion strategies. We evaluated 93 patients who underwent allogeneic hematopoietic stem cell transplantation (HSCT) and analyzed the association between T cell depletion strategies with the cumulative incidence of relapse and CMV reactivation. A total of 33% of patients who received ATG vs. 34% who received alemtuzumab developed CMV reactivation. The cumulative incidence of relapse was 3% at 1year and 20% at 3 years in patients with CMV reactivation vs. 30% at 1year and 38% at 3 years in patients without CMV reactivation (p=0.02). When analyzed separately, this effect persisted in the myeloid, but not the lymphoid group. There was a numerical trend towards increased non-relapse mortality (NRM) in patients with CMV reactivation, especially in the myeloid group. The choice of T cell depleting agent and the rate of CMV reactivation were not associated with different overall survival (OS) rates. These results suggest that the choice of T cell depletion strategy may have similar effects on rates of CMV reactivation, disease relapse, and survival. Further studies examining these variables in patients not exposed to in-vivo T cell depleting agents may be of interest. Copyright © 2017 Elsevier Ltd. All rights reserved.

Inhibition of histone deacetylases 1 and 6 enhances cytarabine-induced apoptosis in pediatric acute myeloid leukemia cells.

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Xu, Xuelian; Xie, Chengzhi; Edwards, Holly; Zhou, Hui; Buck, Steven A; Ge, Yubin

2011-02-16

Pediatric acute myeloid leukemia (AML) remains a challenging disease to treat even with intensified cytarabine-based chemotherapy. Histone deacetylases (HDACs) have been reported to be promising therapeutic targets for treating AML. However, HDAC family members that are involved in chemotherapy sensitivities remain unknown. In this study, we sought to identify members of the HDAC family that are involved in cytarabine sensitivities, and to select the optimal HDACI that is most efficacious when combined with cytarabine for treating children with AML. Expression profiles of classes I, II, and IV HDACs in 4 pediatric AML cell lines were determined by Western blotting. Inhibition of class I HDACs by different HDACIs was measured post immnunoprecipitation. Individual down-regulation of HDACs in pediatric AML cells was performed with lentiviral shRNA. The effects of cytarabine and HDACIs on apoptosis were determined by flow cytometry analysis. Treatments with structurally diverse HDACIs and HDAC shRNA knockdown experiments revealed that down-regulation of both HDACs 1 and 6 is critical in enhancing cytarabine-induced apoptosis in pediatric AML, at least partly mediated by Bim. However, down-regulation of HDAC2 may negatively impact cytarabine sensitivities in the disease. At clinically achievable concentrations, HDACIs that simultaneously inhibited both HDACs 1 and 6 showed the best anti-leukemic activities and significantly enhanced cytarabine-induced apoptosis. Our results further confirm that HDACs are bona fide therapeutic targets for treating pediatric AML and suggest that pan-HDACIs may be more beneficial than isoform-specific drugs.

Deletion of Rac1GTPase in the Myeloid Lineage Protects against Inflammation-Mediated Kidney Injury in Mice.

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Miki Nagase

Full Text Available Macrophage-mediated inflammation has been implicated in various kidney diseases. We previously reported that Rac1, a Rho family small GTP-binding protein, was overactivated in several chronic kidney disease models, and that Rac1 inhibitors ameliorated renal injury, in part via inhibition of inflammation, but the detailed mechanisms have not been clarified. In the present study, we examined whether Rac1 in macrophages effects cytokine production and the inflammatory mechanisms contributing to kidney derangement. Myeloid-selective Rac1 flox control (M-Rac1 FC and knockout (M-Rac1 KO mice were generated using the cre-loxP system. Renal function under basal conditions did not differ between M-Rac1 FC and KO mice. Accordingly, lipopolysaccharide (LPS-evoked kidney injury model was created. LPS elevated blood urea nitrogen and serum creatinine, enhanced expressions of kidney injury biomarkers, Kim-1 and Ngal, and promoted tubular injury in M-Rac1 FC mice. By contrast, deletion of myeloid Rac1 almost completely prevented the LPS-mediated renal impairment. LPS triggered a marked induction of macrophage-derived inflammatory cytokines, IL-6 and TNFα, in M-Rac1 FC mice, which was accompanied by Rac1 activation, stimulation of reduced nicotinamide-adenine dinucleotide phosphate (NADPH oxidase, and reactive oxygen species overproduction. These changes were inhibited in M-Rac1 KO mice. LPS evoked F4/80-positive macrophages accumulation in the kidney, which was not affected by myeloid Rac1 deficiency. We further tested the role of Rac1 signaling in cytokine production using macrophage cell line, RAW264.7. Exposure to LPS increased IL-6 and TNFα mRNA expression. The LPS-driven cytokine induction was dose-dependently blocked by the Rac1 inhibitor EHT1864, NADPH oxidase inhibitor diphenyleneiodonium, and NF-κB inhibitor BAY11-7082. In conclusion, genetic ablation of Rac1 in the myeloid lineage protected against LPS-induced renal inflammation and injury, by

RUNX1/AML1 point mutations take part in the pathogenesis of radiation-and therapy-related myeloid neoplasms

International Nuclear Information System (INIS)

Harada, Yuka; Kimura, Akiro; Harada, Hironori

2012-01-01

High frequency of myelodysplastic syndrome (MDS) has been reported in Hiroshima A-bomb exposed survivors, in resident around Semipalatinsk Nuclear Laboratory and in exposed people by Chernobyl Nuclear Power Station Accident. MDS/acute myeloid leukemia (AML) is thought to be caused by mutation of runt-related transcription factor 1 (RUNX1) gene after a long time post exposure to relatively low dose radiation. In this study, participation of RUNX1/AML1 point mutations was examined in pathogenesis of the title neoplasms experienced in authors' facility. Subjects were 18/417 cases in whom myeloproliferative neoplasms (MPN) had switched to MDS or AML in the follow-up period of 1-25 years, and 11/124 cases in whom t-MN (therapy-related myeloid neoplasms) had developed during the remission of acute promyelocytic leukemia (APL) in the 1-9.7 years follow up. Point mutations were analyzed by PCR-single strand conformation polymorphism (PCR-SSCP) followed by base sequencing. In the former cases above, RUNX1 point mutation was found in 5/18 cases and in the latter, 4/11. When patients with persistent decrease of blood cells post therapy of APL were followed up for mutation, their RUNX1 point mutation was detected before they were diagnosed to be morbid of MDS/AML. The point mutation was thus a biomarker of myelo-hematogenic cancer, and was thought useful for early diagnosis of MDS and AML. (T.T.)

The role of peptide and DNA vaccines in myeloid leukemia immunotherapy

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Lin Chen

2013-02-01

Full Text Available Abstract While chemotherapy and targeted therapy are successful in inducing the remission of myeloid leukemia as acute myeloid leukemia (AML and chronic myeloid leukemia (CML, the disease remains largely incurable. This observation is likely due to the drug resistance of leukemic cells, which are responsible for disease relapse. Myeloid leukemia vaccines may most likely be beneficial for eradicating minimal residual disease after treatment with chemotherapy or targeted therapy. Several targeted immunotherapies using leukemia vaccines have been heavily investigated in clinical and preclinical trials. This review will focus on peptides and DNA vaccines in the context of myeloid leukemias, and optimal strategies for enhancing the efficacy of vaccines based on myeloid leukemia immunization are also summarized.

Oncogenic RAS enables DNA damage- and p53-dependent differentiation of acute myeloid leukemia cells in response to chemotherapy.

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Mona Meyer

Full Text Available Acute myeloid leukemia (AML is a clonal disease originating from myeloid progenitor cells with a heterogeneous genetic background. High-dose cytarabine is used as the standard consolidation chemotherapy. Oncogenic RAS mutations are frequently observed in AML, and are associated with beneficial response to cytarabine. Why AML-patients with oncogenic RAS benefit most from high-dose cytarabine post-remission therapy is not well understood. Here we used bone marrow cells expressing a conditional MLL-ENL-ER oncogene to investigate the interaction of oncogenic RAS and chemotherapeutic agents. We show that oncogenic RAS synergizes with cytotoxic agents such as cytarabine in activation of DNA damage checkpoints, resulting in a p53-dependent genetic program that reduces clonogenicity and increases myeloid differentiation. Our data can explain the beneficial effects observed for AML patients with oncogenic RAS treated with higher dosages of cytarabine and suggest that induction of p53-dependent differentiation, e.g. by interfering with Mdm2-mediated degradation, may be a rational approach to increase cure rate in response to chemotherapy. The data also support the notion that the therapeutic success of cytotoxic drugs may depend on their ability to promote the differentiation of tumor-initiating cells.

Chimeric antigen receptors for adoptive T cell therapy in acute myeloid leukemia

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Mingxue Fan

2017-08-01

Full Text Available Abstract Currently, conventional therapies for acute myeloid leukemia (AML have high failure and relapse rates. Thus, developing new strategies is crucial for improving the treatment of AML. With the clinical success of anti-CD19 chimeric antigen receptor (CAR T cell therapies against B-lineage malignancies, many studies have attempted to translate the success of CAR T cell therapy to other malignancies, including AML. This review summarizes the current advances in CAR T cell therapy against AML, including preclinical studies and clinical trials, and discusses the potential AML-associated surface markers that could be used for further CAR technology. Finally, we describe strategies that might address the current issues of employing CAR T cell therapy in AML.

Specific Inhibition of the VEGFR-3 Tyrosine Kinase by SAR131675 Reduces Peripheral and Tumor Associated Immunosuppressive Myeloid Cells

Energy Technology Data Exchange (ETDEWEB)

Espagnolle, Nicolas [UMR5273 INSERM U1031/CNRS/EFS StromaLab, Toulouse 31432 (France); Barron, Pauline; Mandron, Marie; Blanc, Isabelle; Bonnin, Jacques [Sanofi Recherche et Développement, Early to Candidate DPU, Toulouse 31036 (France); Agnel, Magali; Kerbelec, Erwan [Molecular Biology Unit, Biologics Department, Sanofi, Vitry-sur-Seine 94400 (France); Herault, Jean Pascal; Savi, Pierre; Bono, Françoise; Alam, Antoine, E-mail: antoine.alam@sanofi.com [Sanofi Recherche et Développement, Early to Candidate DPU, Toulouse 31036 (France)

2014-02-28

Myeloid derived suppressor cells (MDSCs) and tumor-associated macrophages (TAMs) represent prominent components in cancer progression. We previously showed that inhibition of the VEGFR-3 pathway by SAR131675 leads to reduction of TAM infiltration and tumor growth. Here, we found that treatment with SAR131675 prevents the accumulation of immunosuppressive blood and splenic MDSCs which express VEGFR-3, in 4T1 tumor bearing mice. Moreover we showed that soluble factors secreted by tumor cells promote MDSCs proliferation and differentiation into M2 polarized F4/80+ macrophages. In addition, cell sorting and transcriptomic analysis of tumor infiltrating myeloid cells revealed the presence of a heterogeneous population that could be divided into 3 subpopulations: (i) immature cells with a MDSC phenotype (GR1+/CD11b+/F4/80{sup −}); (ii) “immuno-incompetent” macrophages (F4/80{sup high}/CD86{sup neg}/MHCII{sup Low}) strongly expressing M2 markers such as Legumain, CD206 and Mgl1/2 and (iii) “immuno-competent”-M1 like macrophages (F4/80{sup Low}/CD86{sup +}/MHCII{sup High}). SAR131675 treatment reduced MDSCs in lymphoid organs as well as F4/80{sup High} populations in tumors. Interestingly, in the tumor SAR131675 was able to increase the immunocompetent M1 like population (F4/80{sup low}). Altogether these results demonstrate that the specific VEGFR-3 inhibitor SAR131675 exerts its anti tumoral activity by acting on different players that orchestrate immunosuppression and cancer progression in a tumoral context: MDSCs in peripheral lymphoid organs and TAMs infiltrating the tumor.

Heme oxygenase-1: A new druggable target in the management of chronic and acute myeloid leukemia.

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Salerno, Loredana; Romeo, Giuseppe; Modica, Maria N; Amata, Emanuele; Sorrenti, Valeria; Barbagallo, Ignazio; Pittalà, Valeria

2017-12-15

Heme oxygenase-1 (HO-1) is the enzyme catalyzing the rate-limiting oxidative degradation of cellular heme into free iron, carbon monoxide (CO), and biliverdin, which is then rapidly converted into bilirubin. By means of these catabolic end-products and by removal of pro-oxidant heme, HO-1 exerts antioxidant, antiapoptotic, and immune-modulating effects, leading to overall cytoprotective and beneficial functions in mammalian cells. Therefore, HO-1 is considered a survival molecule in various stress-related conditions. By contrast, growing evidence suggests that HO-1 is a survival-enhancing molecule also in various solid and blood cancers, such as various types of leukemia, promoting carcinogenesis, tumor progression, and chemo-resistance. Among leukemias, chronic myeloid leukemia (CML) is currently therapeutically well treated with tyrosine kinase inhibitors (TKIs) such as Imatinib (IM) and its congeners; nevertheless, resistance to all kinds of current drugs persist in a number of patients. Moreover, treatment outcomes for acute myeloid leukemia (AML) remain unsatisfactory, despite progress in chemotherapy and hematopoietic stem cell transplantation. Therefore, identification of new eligible targets that may improve leukemias therapy is of general interest. Several recent papers prove that inhibition of HO-1 through HO-1 inhibitors as well as modulation of other pathways involving HO-1 by a number of different new or known molecules, are critical for leukemia treatment. This review summarizes the current understanding of the pro-tumorigenic role of HO-1 and its potential as a molecular target for the treatment of leukemias. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Reduced Intensity Donor Peripheral Blood Stem Cell Transplant in Treating Patients With De Novo or Secondary Acute Myeloid Leukemia in Remission

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2018-05-24

Acute Myeloid Leukemia With Multilineage Dysplasia Following Myelodysplastic Syndrome; Adult Acute Megakaryoblastic Leukemia (M7); Adult Acute Minimally Differentiated Myeloid Leukemia (M0); Adult Acute Monoblastic Leukemia (M5a); Adult Acute Monocytic Leukemia (M5b); Adult Acute Myeloblastic Leukemia With Maturation (M2); Adult Acute Myeloblastic Leukemia Without Maturation (M1); Adult Acute Myeloid Leukemia in Remission; Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Del(5q); Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Adult Acute Myelomonocytic Leukemia (M4); Adult Erythroleukemia (M6a); Adult Pure Erythroid Leukemia (M6b); Secondary Acute Myeloid Leukemia

Vorinostat and Decitabine in Treating Patients With Advanced Solid Tumors or Relapsed or Refractory Non-Hodgkin's Lymphoma, Acute Myeloid Leukemia, Acute Lymphocytic Leukemia, or Chronic Myelogenous Leukemia

Science.gov (United States)

2014-08-26

Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Blastic Phase Chronic Myelogenous Leukemia; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Nodal Marginal Zone B-cell Lymphoma; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Acute Myeloid Leukemia; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Small Lymphocytic Lymphoma; Secondary Acute Myeloid Leukemia; Splenic Marginal Zone Lymphoma; Stage III Adult Burkitt Lymphoma; Stage III Adult Diffuse Large Cell Lymphoma; Stage III Adult Diffuse Mixed Cell Lymphoma; Stage III Adult Diffuse Small Cleaved Cell Lymphoma; Stage III Adult Immunoblastic Large Cell Lymphoma; Stage III Adult Lymphoblastic Lymphoma; Stage III Grade 1 Follicular Lymphoma; Stage III Grade 2 Follicular Lymphoma; Stage III Grade 3 Follicular Lymphoma; Stage III Mantle Cell Lymphoma; Stage III Marginal Zone Lymphoma; Stage III Small Lymphocytic Lymphoma; Stage IV Adult Burkitt Lymphoma; Stage IV Adult Diffuse Large Cell Lymphoma; Stage IV Adult Diffuse Mixed Cell Lymphoma; Stage IV Adult Diffuse Small Cleaved Cell Lymphoma; Stage IV Adult Immunoblastic Large Cell Lymphoma; Stage IV Adult Lymphoblastic Lymphoma; Stage IV Grade 1 Follicular Lymphoma; Stage IV Grade 2 Follicular Lymphoma; Stage IV Grade 3 Follicular Lymphoma; Stage IV Mantle Cell Lymphoma; Stage IV Marginal Zone Lymphoma

KRAS (G12D Cooperates with AML1/ETO to Initiate a Mouse Model Mimicking Human Acute Myeloid Leukemia

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Shanmin Zhao

2014-01-01

Full Text Available Background/Aims: It has been demonstrated that KRAS mutations represent about 90% of cancer-associated mutations, and that KRAS mutations play an essential role in neoplastic transformation. Cancer-associated RAS mutations occur frequently in acute myeloid leukemia (AML, suggesting a functional role for Ras in leukemogenesis. Methods: We successfully established a mouse model of human leukemia by transplanting bone marrow cells co-transfected with the K-ras (G12D mutation and AML1/ETO fusion protein. Results: Mice transplanted with AML/ETO+KRAS co-transduced cells had the highest mortality rate than mice transplanted with AML/ETO- or KRAS-transduced cells (115d vs. 150d. Upon reaching a terminal disease stage, EGFP-positive cells dominated their spleen, lymph nodes, peripheral blood and central nervous system tissue. Immunophenotyping, cytologic analyses revealed that AML/ETO+KRAS leukemias predominantly contained immature myeloid precursors (EGFP+/c-Kit+/Mac-1-/Gr-1-. Histologic analyses revealed that massive leukemic infiltrations were closely packed in dense sheets that effaced the normal architecture of spleen and thymus in mice transplanted with AML1/ETO + KRAS co-transduced cells. K-ras mRNA and protein expression were upregulated in bone marrow cells of the K-ras group and AML1/ETO + Kras group. The phosphorylation of MEK/ERK was significantly enhanced in the AML1/ETO + Kras group. The similar results of the AML1/ETO + Nras group were consistent with those reported previously. Conclusion: Co-transduction of KrasG12D and AML1/ETO induces acute monoblastic leukemia. Since expression of mutant K-ras alone was insufficient to induce leukemia, this model may be useful for investigating the multi-step leukemogenesis model of human leukemia.

Selective blockade of B7-H3 enhances antitumour immune activity by reducing immature myeloid cells in head and neck squamous cell carcinoma.

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Mao, Liang; Fan, Teng-Fei; Wu, Lei; Yu, Guang-Tao; Deng, Wei-Wei; Chen, Lei; Bu, Lin-Lin; Ma, Si-Rui; Liu, Bing; Bian, Yansong; Kulkarni, Ashok B; Zhang, Wen-Feng; Sun, Zhi-Jun

2017-09-01

Immature myeloid cells including myeloid-derived suppressor cells (MDSCs) and tumour-associated macrophages (TAMs) promote tumour growth and metastasis by facilitating tumour transformation and angiogenesis, as well as by suppressing antitumour effector immune responses. Therefore, strategies designed to reduce MDSCs and TAMs accumulation and their activities are potentially valuable therapeutic goals. In this study, we show that negative immune checkpoint molecule B7-H3 is significantly overexpressed in human head and neck squamous cell carcinoma (HNSCC) specimen as compared with normal oral mucosa. Using immunocompetent transgenic HNSCC models, we observed that targeting inhibition of B7-H3 reduced tumour size. Flow cytometry analysis revealed that targeting inhibition of B7-H3 increases antitumour immune response by decreasing immunosuppressive cells and promoting cytotoxic T cell activation in both tumour microenvironment and macroenvironment. Our study provides direct in vivo evidence for a rationale for B7-H3 blockade as a future therapeutic strategy to treat patients with HNSCC. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

Regulation of Human Macrophage M1–M2 Polarization Balance by Hypoxia and the Triggering Receptor Expressed on Myeloid Cells-1

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Federica Raggi

2017-09-01

Full Text Available Macrophages (Mf are a heterogeneous population of tissue-resident professional phagocytes and a major component of the leukocyte infiltrate at sites of inflammation, infection, and tumor growth. They can undergo diverse forms of activation in response to environmental factors, polarizing into specialized functional subsets. A common hallmark of the pathologic environment is represented by hypoxia. The impact of hypoxia on human Mf polarization has not been fully established. The objective of this study was to elucidate the effects of a hypoxic environment reflecting that occurring in vivo in diseased tissues on the ability of human Mf to polarize into classically activated (proinflammatory M1 and alternatively activated (anti-inflammatory M2 subsets. We present data showing that hypoxia hinders Mf polarization toward the M1 phenotype by decreasing the expression of T cell costimulatory molecules and chemokine homing receptors and the production of proinflammatory, Th1-priming cytokines typical of classical activation, while promoting their acquisition of phenotypic and secretory features of alternative activation. Furthermore, we identify the triggering receptor expressed on myeloid cells (TREM-1, a member of the Ig-like immunoregulatory receptor family, as a hypoxia-inducible gene in Mf and demonstrate that its engagement by an agonist Ab reverses the M2-polarizing effect of hypoxia imparting a M1-skewed phenotype to Mf. Finally, we provide evidence that Mf infiltrating the inflamed hypoxic joints of children affected by oligoarticular juvenile idiopatic arthritis express high surface levels of TREM-1 associated with predominant M1 polarization and suggest the potential of this molecule in driving M1 proinflammatory reprogramming in the hypoxic synovial environment.

Regulation of Human Macrophage M1–M2 Polarization Balance by Hypoxia and the Triggering Receptor Expressed on Myeloid Cells-1

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Raggi, Federica; Pelassa, Simone; Pierobon, Daniele; Penco, Federica; Gattorno, Marco; Novelli, Francesco; Eva, Alessandra; Varesio, Luigi; Giovarelli, Mirella; Bosco, Maria Carla

2017-01-01

Macrophages (Mf) are a heterogeneous population of tissue-resident professional phagocytes and a major component of the leukocyte infiltrate at sites of inflammation, infection, and tumor growth. They can undergo diverse forms of activation in response to environmental factors, polarizing into specialized functional subsets. A common hallmark of the pathologic environment is represented by hypoxia. The impact of hypoxia on human Mf polarization has not been fully established. The objective of this study was to elucidate the effects of a hypoxic environment reflecting that occurring in vivo in diseased tissues on the ability of human Mf to polarize into classically activated (proinflammatory M1) and alternatively activated (anti-inflammatory M2) subsets. We present data showing that hypoxia hinders Mf polarization toward the M1 phenotype by decreasing the expression of T cell costimulatory molecules and chemokine homing receptors and the production of proinflammatory, Th1-priming cytokines typical of classical activation, while promoting their acquisition of phenotypic and secretory features of alternative activation. Furthermore, we identify the triggering receptor expressed on myeloid cells (TREM)-1, a member of the Ig-like immunoregulatory receptor family, as a hypoxia-inducible gene in Mf and demonstrate that its engagement by an agonist Ab reverses the M2-polarizing effect of hypoxia imparting a M1-skewed phenotype to Mf. Finally, we provide evidence that Mf infiltrating the inflamed hypoxic joints of children affected by oligoarticular juvenile idiopatic arthritis express high surface levels of TREM-1 associated with predominant M1 polarization and suggest the potential of this molecule in driving M1 proinflammatory reprogramming in the hypoxic synovial environment. PMID:28936211

Clinical relevance of IDH1/2 mutant allele burden during follow-up in acute myeloid leukemia. A study by the French ALFA group

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Ferret, Yann; Boissel, Nicolas; Helevaut, Nathalie; Madic, Jordan; Nibourel, Olivier; Marceau-Renaut, Alice; Bucci, Maxime; Geffroy, Sandrine; Celli-Lebras, Karine; Castaigne, Sylvie; Thomas, Xavier; Terré, Christine; Dombret, Hervé; Preudhomme, Claude; Renneville, Aline

2018-01-01

Assessment of minimal residual disease has emerged as a powerful prognostic factor in acute myeloid leukemia. In this study, we investigated the potential of IDH1/2 mutations as targets for minimal residual disease assessment in acute myeloid leukemia, since these mutations collectively occur in 15–20% of cases of acute myeloid leukemia and now represent druggable targets. We employed droplet digital polymerase chain reaction assays to quantify IDH1R132, IDH2R140, and IDH2R172 mutations on genomic DNA in 322 samples from 103 adult patients with primary IDH1/2 mutant acute myeloid leukemia and enrolled on Acute Leukemia French Association (ALFA) - 0701 or -0702 clinical trials. The median IDH1/2 mutant allele fraction in bone marrow samples was 42.3% (range, 8.2 – 49.9%) at diagnosis of acute myeloid leukemia, and below the detection limit of 0.2% (range, <0.2 – 39.3%) in complete remission after induction therapy. In univariate analysis, the presence of a normal karyotype, a NPM1 mutation, and an IDH1/2 mutant allele fraction <0.2% in bone marrow after induction therapy were statistically significant predictors of longer disease-free survival. In multivariate analysis, these three variables remained significantly predictive of disease-free survival. In 7/103 (7%) patients, IDH1/2 mutations persisted at high levels in complete remission, consistent with the presence of an IDH1/2 mutation in pre-leukemic hematopoietic stem cells. Five out of these seven patients subsequently relapsed or progressed toward myelodysplastic syndrome, suggesting that patients carrying the IDH1/2 mutation in a pre-leukemic clone may be at high risk of hematologic evolution. PMID:29472349

Elevated Mcl-1 perturbs lymphopoiesis, promotes transformation of hematopoietic stem/progenitor cells, and enhances drug resistance

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Campbell, Kirsteen J.; Bath, Mary L.; Turner, Marian L.; Vandenberg, Cassandra J.; Bouillet, Philippe; Metcalf, Donald; Scott, Clare L.; Cory, Suzanne

2010-01-01

Diverse human cancers with poor prognosis, including many lymphoid and myeloid malignancies, exhibit high levels of Mcl-1. To explore the impact of Mcl-1 overexpression on the hematopoietic compartment, we have generated vavP-Mcl-1 transgenic mice. Their lymphoid and myeloid cells displayed increased resistance to a variety of cytotoxic agents. Myelopoiesis was relatively normal, but lymphopoiesis was clearly perturbed, with excess mature B and T cells accumulating. Rather than the follicular...

Luteoloside Inhibits Proliferation of Human Chronic Myeloid ...

African Journals Online (AJOL)

Purpose: To investigate the effects of luteoloside on the proliferation of human chronic myeloid leukemia K562 cells and whether luteoloside induces cell cycle arrest and apoptosis in K562 cells. Methods: Luteoloside's cytotoxicity was assessed using a cell counting kit. Cell cycle distribution was analysed by flow cytometry ...

miR-181a promotes G1/S transition and cell proliferation in pediatric acute myeloid leukemia by targeting ATM.

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Liu, Xiaodan; Liao, Wang; Peng, Hongxia; Luo, Xuequn; Luo, Ziyan; Jiang, Hua; Xu, Ling

2016-01-01

Abnormal expression of miRNAs is intimately related to a variety of human cancers. The purpose of this study is to confirm the expression of miR-181a and elucidate its physiological function and mechanism in pediatric acute myeloid leukemia (AML). Pediatric AML patients and healthy controls were enrolled, and the expression of miR-181a and ataxia telangiectasia mutated (ATM) in tissues were examined using quantitative PCR. Moreover, cell proliferation and cell cycle were evaluated in several cell lines (HL60, NB4 and K562) by using flow cytometry after transfected with miR-181a mimics and inhibitors, or ATM siRNA and control siRNA. Finally, ATM as the potential target protein of miR-181a was examined. We found that miR-181a was significantly increased in pediatric AML, which showed an inverse association with ATM expression. Overexpressed miR-181a in cell lines significantly enhanced cell proliferation, as well as increased the ratio of S-phase cells by miR-181a mimics transfection in vitro. Luciferase activity of the reporter construct identified ATM as the direct molecular target of miR-181a. ATM siRNA transfection significantly enhanced cell proliferation and increased the ratio of S-phase cells in vitro. The results revealed novel mechanism through which miR-181a regulates G1/S transition and cell proliferation in pediatric AML by regulating the tumor suppressor ATM, providing insights into the molecular mechanism in pediatric AML.

Clinical presentation of acute myeloid leukaemia - A decade-long institutional follow-up.

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Kulsoom, Bibi; Shamsi, Tahir Sultan; Ahmed, Nikhat; Hasnain, Syed Nazrul

2017-12-01

To analyse a decade-long pattern of clinical presentation of acute myeloid leukaemia patients and compare it with contemporary data. The retrospective cohort study was conducted at the National Institute of Blood Diseases and Bone Marrow Transplantation, Karachi, and comprised of medical record of acute myeloid leukaemia patients from March 2006 to October 2016. Data noted age at presentation, gender, medical history, physical examination, blood and bone marrow investigations such as, haemoglobin levels, blood cell count myeloperoxidase activity, periodic acid-Schiff and reticulin staining as well as final diagnosis. Comparison, where possible, was done with contemporary literature. SPSS 19 was used for data analysis. Of the 626 subjects, 248(39.6%) were females and 378(60.4%) males. The overall mean age was 35.3±17.1 years. The most common age group was 15-40 years with 354(56.5%) patients. The most common subtype was acute myeloid leukaemia with maturation 183(33.6%). Myeloperoxidase activity was positive for the majority of the acute myeloid leukaemia patients. Periodic acid-Schiff test, done on only selected patients, was mostly negative. Reticulin staining was positive for 113(65.3%) patients. The most common presenting complaints were fever 266(71.9%) and weakness 168(45.4%). Mean haemoglobin and red blood cell count were 8.3 ± 2.4 g/dL and 2.9 ± 1.2 1012/L, respectively. Acute myeloid leukaemia was found to be a highly variable disease that presented with non-specific signs and symptoms.

Tumor SHB gene expression affects disease characteristics in human acute myeloid leukemia.

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Jamalpour, Maria; Li, Xiujuan; Cavelier, Lucia; Gustafsson, Karin; Mostoslavsky, Gustavo; Höglund, Martin; Welsh, Michael

2017-10-01

The mouse Shb gene coding for the Src Homology 2-domain containing adapter protein B has recently been placed in context of BCRABL1-induced myeloid leukemia in mice and the current study was performed in order to relate SHB to human acute myeloid leukemia (AML). Publicly available AML databases were mined for SHB gene expression and patient survival. SHB gene expression was determined in the Uppsala cohort of AML patients by qPCR. Cell proliferation was determined after SHB gene knockdown in leukemic cell lines. Despite a low frequency of SHB gene mutations, many tumors overexpressed SHB mRNA compared with normal myeloid blood cells. AML patients with tumors expressing low SHB mRNA displayed longer survival times. A subgroup of AML exhibiting a favorable prognosis, acute promyelocytic leukemia (APL) with a PMLRARA translocation, expressed less SHB mRNA than AML tumors in general. When examining genes co-expressed with SHB in AML tumors, four other genes ( PAX5, HDAC7, BCORL1, TET1) related to leukemia were identified. A network consisting of these genes plus SHB was identified that relates to certain phenotypic characteristics, such as immune cell, vascular and apoptotic features. SHB knockdown in the APL PMLRARA cell line NB4 and the monocyte/macrophage cell line MM6 adversely affected proliferation, linking SHB gene expression to tumor cell expansion and consequently to patient survival. It is concluded that tumor SHB gene expression relates to AML survival and its subgroup APL. Moreover, this gene is included in a network of genes that plays a role for an AML phenotype exhibiting certain immune cell, vascular and apoptotic characteristics.

Loss of C/EBP alpha cell cycle control increases myeloid progenitor proliferation and transforms the neutrophil granulocyte lineage

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Porse, Bo T; Bryder, David; Theilgaard-Mönch, Kim

2005-01-01

dissociate the ability of C/EBP alpha to block cell cycle progression through E2F inhibition from its function as a transcriptional activator impair the in vivo development of the neutrophil granulocyte and adipose lineages. We now show that such mutations increase the capacity of bone marrow (BM) myeloid...... progenitors to proliferate, and predispose mice to a granulocytic myeloproliferative disorder and transformation of the myeloid compartment of the BM. Both of these phenotypes were transplantable into lethally irradiated recipients. BM transformation was characterized by a block in granulocyte differentiation...

Activated NKT cells facilitated functional switch of myeloid-derived suppressor cells at inflammation sites in fulminant hepatitis mice.

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Wu, Danxiao; Shi, Yu; Wang, Cheng; Chen, Hanwen; Liu, Qiaoyun; Liu, Jianhua; Zhang, Lihuang; Wu, Yihua; Xia, Dajing

2017-02-01

Myeloid-derived suppressor cells (MDSCs) confer immunosuppressive properties, but their roles in fulminant hepatitis have not been well defined. In this study, we systematically examined the distribution of MDSCs in bone marrow (BM), liver and spleen, and their functional and differentiation status in an acute fulminant hepatitis mouse model induced by lipopolysaccharide and D-galactosamine (LPS-GalN). Moreover, the interaction between NKT cells and MDSCs was determined. Our study revealed that BM contained the largest pool of MDSCs during pathogenesis of fulminant hepatitis compared with liver and spleen. MDSCs in liver/spleen expressed higher levels of chemokine receptors such as CCR2, CX3CR1 and CXCR2. At inflamed tissues such as liver or spleen, activated NKT cells induced differentiation of MDSCs through cell-cell interaction, which markedly dampened the immunosuppressive effects and promoted MDSCs to produce pro-inflammatory cytokines and activate inflammatory cells. Our findings thus demonstrated an unexpected pro-inflammatory state for MDSCs, which was mediated by the activated NKT cells that precipitated the differentiation and functional evolution of these MDSCs at sites of inflammation. Copyright © 2016. Published by Elsevier GmbH.

Control of proliferating potential of myeloid leukemia cells during long-term treatment with vitamin D3 analogues and other differentiation inducers in combination with antileukemic drugs: in vitro and in vivo studies.

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Kasukabe, T; Honma, Y; Hozumi, M; Suda, T; Nishii, Y

1987-01-15

Growth inhibition of murine and human myeloid leukemia cells by differentiation inducers during long-term culture was examined to improve the strategy for therapy of myeloid leukemia by differentiation inducers. When the effect of 1 alpha,25-dihydroxyvitamin D3, a typical differentiation inducer, on proliferation of mouse myeloid leukemia M1 cells was examined at a constant product of time and concentration (480 nM in 20 days), the continuous treatment with 24 nM 1 alpha,25-dihydroxyvitamin D3 was the most effective for inhibition of cell proliferation. After 20 days, the cumulative cell number was reduced about 3 X 10(5) times by continuous treatment with 24 nM 1 alpha,25-dihydroxyvitamin D3. Similar results were obtained when M1 cells were treated continuously with dexamethasone. M1 cells resistant to 1 alpha,25-dihydroxyvitamin D3 appeared about 25 days after the start of continuous treatment with 24 nM 1 alpha,25-dihydroxyvitamin D3. On the other hand, when M1 cells were treated continuously with 1 alpha,25-dihydroxyvitamin D3 and noncytotoxic doses of antileukemic drugs such as 1-beta-D-arabinofuranosylcytosine and daunomycin, resistant cells did not appear for at least 35 days. A similar effect of 1 alpha,25-dihydroxyvitamin D3 and antileukemic drugs on cell proliferation was observed with the human monoblast-like cell line U937. The survival of syngeneic SL mice inoculated with M1 cells was prolonged more by treatment with both 1 alpha-hydroxyvitamin D3 and daunomycin than by treatment with either drug alone. These results suggest that continuous treatment with both differentiation inducers and certain antileukemic drugs may be more effective therapeutically than treatment with a differentiation inducer alone.

Functional Impairment of Myeloid Dendritic Cells during Advanced Stage of HIV-1 Infection: Role of Factors Regulating Cytokine Signaling.

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Meenakshi Sachdeva

Full Text Available Severely immunocompromised state during advanced stage of HIV-1 infection has been linked to functionally defective antigen presentation by dendritic cells (DCs. The molecular mechanisms behind DC impairment are still obscure. We investigated changes in DC function and association of key regulators of cytokine signaling during different stages of HIV-1 infection and following antiretroviral therapy (ART.Phenotypic and functional characteristics of circulating myeloid DCs (mDCs in 56 ART-naive patients (23 in early and 33 in advanced stage of disease, 36 on ART and 24 healthy controls were evaluated. Sixteen patients were studied longitudinally prior-to and 6 months after the start of ART. For functional studies, monocyte-derived DCs (Mo-DCs were evaluated for endocytosis, allo-stimulation and cytokine secretion. The expression of suppressor of cytokine signaling (SOCS-1 and other regulators of cytokine signaling was evaluated by real-time RT-PCR.The ability to respond to an antigenic stimulation was severely impaired in patients in advanced HIV-1 disease which showed partial recovery in the treated group. Mo-DCs from patients with advanced HIV-disease remained immature with low allo-stimulation and reduced cytokine secretion even after TLR-4 mediated stimulation ex-vivo. The cells had an increased expression of negative regulatory factors like SOCS-1, SOCS-3, SH2-containing phosphatase (SHP-1 and a reduced expression of positive regulators like Janus kinase (JAK2 and Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB1. A functional recovery after siRNA mediated silencing of SOCS-1 in these mo-DCs confirms the role of negative regulatory factors in functional impairment of these cells.Functionally defective DCs in advanced stage of HIV-1 infection seems to be due to imbalanced state of negative and positive regulatory gene expression. Whether this is a cause or effect of increased viral replication at this stage of disease

Role of myeloid-derived suppressor cells in amelioration of experimental autoimmune hepatitis following activation of TRPV1 receptors by cannabidiol.

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Venkatesh L Hegde

2011-04-01

Full Text Available Myeloid-derived suppressor cells (MDSCs are getting increased attention as one of the main regulatory cells of the immune system. They are induced at sites of inflammation and can potently suppress T cell functions. In the current study, we demonstrate how activation of TRPV1 vanilloid receptors can trigger MDSCs, which in turn, can inhibit inflammation and hepatitis.Polyclonal activation of T cells, following injection of concanavalin A (ConA, in C57BL/6 mice caused acute hepatitis, characterized by significant increase in aspartate transaminase (AST, induction of inflammatory cytokines, and infiltration of mononuclear cells in the liver, leading to severe liver injury. Administration of cannabidiol (CBD, a natural non-psychoactive cannabinoid, after ConA challenge, inhibited hepatitis in a dose-dependent manner, along with all of the associated inflammation markers. Phenotypic analysis of liver infiltrating cells showed that CBD-mediated suppression of hepatitis was associated with increased induction of arginase-expressing CD11b(+Gr-1(+ MDSCs. Purified CBD-induced MDSCs could effectively suppress T cell proliferation in vitro in arginase-dependent manner. Furthermore, adoptive transfer of purified MDSCs into naïve mice conferred significant protection from ConA-induced hepatitis. CBD failed to induce MDSCs and suppress hepatitis in the livers of vanilloid receptor-deficient mice (TRPV1(-/- thereby suggesting that CBD primarily acted via this receptor to induce MDSCs and suppress hepatitis. While MDSCs induced by CBD in liver consisted of granulocytic and monocytic subsets at a ratio of ∼2∶1, the monocytic MDSCs were more immunosuppressive compared to granulocytic MDSCs. The ability of CBD to induce MDSCs and suppress hepatitis was also demonstrable in Staphylococcal enterotoxin B-induced liver injury.This study demonstrates for the first time that MDSCs play a critical role in attenuating acute inflammation in the liver, and that agents

Activation of Liver X Receptor Decreases Atherosclerosis in Ldlr−/− mice in the Absence of ABCA1 and ABCG1 in Myeloid Cells

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Kappus, Mojdeh S.; Murphy, Andrew J.; Abramowicz, Sandra; Ntonga, Vusisizwe; Welch, Carrie L.; Tall, Alan R.; Westerterp, Marit

2014-01-01

Objective Liver X Receptor (LXR) activators decrease atherosclerosis in mice. LXR activators (1) directly up-regulate genes involved in reverse cholesterol transport (RCT) and (2) exert anti-inflammatory effects mediated by transrepression of NFκB target genes. We investigated whether myeloid cell deficiency of ATP-binding cassette transporters A1 and G1 (ABCA1/G1), principal targets of LXR that promote macrophage cholesterol efflux and initiate RCT, would abolish the beneficial effects of LXR activation on atherosclerosis. Approach and Results LXR activator T0901317 (T0) substantially reduced inflammatory gene expression in macrophages lacking ABCA1/G1. Ldlr−/− mice were transplanted with Abca1−/−Abcg1−/− or wild-type bone marrow (BM) and fed a Western-type diet (WTD) for 6 weeks with or without T0 supplementation. Abca1/g1 BM deficiency increased atherosclerotic lesion complexity and inflammatory cell infiltration into the adventitia and myocardium. T0 markedly decreased lesion area, complexity and inflammatory cell infiltration in the Abca1−/−Abcg1−/− BM transplanted mice. To investigate whether this was due to macrophage Abca1/g1 deficiency, Ldlr−/− mice were transplanted with LysmCreAbca1fl/flAbcg1fl/fl or Abca1fl/flAbcg1fl/fl BM and fed WTD with or without the more specific LXR agonist GW3965 for 12 weeks. GW3965 decreased lesion size in both groups and the decrease was more prominent in the LysmCreAbca1fl/flAbcg1fl/fl group. Conclusions The results suggest that anti-inflammatory effects of LXR activators are of key importance to their anti-atherosclerotic effects in vivo independent of cholesterol efflux pathways mediated by macrophage ABCA1/G1. This has implications for the development of LXR activators that lack adverse effects on lipogenic genes while maintaining the ability to trans-repress inflammatory genes. PMID:24311381

Vorinostat in Treating Patients With Acute Myeloid Leukemia

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2014-04-30

Adult Acute Erythroid Leukemia (M6); Adult Acute Megakaryoblastic Leukemia (M7); Adult Acute Minimally Differentiated Myeloid Leukemia (M0); Adult Acute Monoblastic Leukemia (M5a); Adult Acute Monocytic Leukemia (M5b); Adult Acute Myeloblastic Leukemia With Maturation (M2); Adult Acute Myeloblastic Leukemia Without Maturation (M1); Adult Acute Myeloid Leukemia With 11q23 (MLL) Abnormalities; Adult Acute Myeloid Leukemia With Inv(16)(p13;q22); Adult Acute Myeloid Leukemia With t(15;17)(q22;q12); Adult Acute Myeloid Leukemia With t(16;16)(p13;q22); Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); Adult Acute Myelomonocytic Leukemia (M4); Adult Acute Promyelocytic Leukemia (M3); Recurrent Adult Acute Myeloid Leukemia; Refractory Cytopenia With Multilineage Dysplasia; Secondary Acute Myeloid Leukemia; Untreated Adult Acute Myeloid Leukemia

Caffeine affects the biological responses of human hematopoietic cells of myeloid lineage via downregulation of the mTOR pathway and xanthine oxidase activity

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Abooali, Maryam; Yasinska, Inna M.; Casely-Hayford, Maxwell A.; Berger, Steffen M.; Fasler-Kan, Elizaveta; Sumbayev, Vadim V.

2015-01-01

Correction of human myeloid cell function is crucial for the prevention of inflammatory and allergic reactions as well as leukaemia progression. Caffeine, a naturally occurring food component, is known to display anti-inflammatory effects which have previously been ascribed largely to its inhibitory actions on phosphodiesterase. However, more recent studies suggest an additional role in affecting the activity of the mammalian target of rapamycin (mTOR), a master regulator of myeloid cell translational pathways, although detailed molecular events underlying its mode of action have not been elucidated. Here, we report the cellular uptake of caffeine, without metabolisation, by healthy and malignant hematopoietic myeloid cells including monocytes, basophils and primary acute myeloid leukaemia mononuclear blasts. Unmodified caffeine downregulated mTOR signalling, which affected glycolysis and the release of pro-inflammatory/pro-angiogenic cytokines as well as other inflammatory mediators. In monocytes, the effects of caffeine were potentiated by its ability to inhibit xanthine oxidase, an enzyme which plays a central role in human purine catabolism by generating uric acid. In basophils, caffeine also increased intracellular cyclic adenosine monophosphate (cAMP) levels which further enhanced its inhibitory action on mTOR. These results demonstrate an important mode of pharmacological action of caffeine with potentially wide-ranging therapeutic impact for treating non-infectious disorders of the human immune system, where it could be applied directly to inflammatory cells. PMID:26384306

Estimation of the target stem-cell population size in chronic myeloid leukemogenesis

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Radivoyevitch, T.; Ramsey, M.J.; Tucker, J.D.

1999-01-01

Estimation of the number of hematopoietic stem cells capable of causing chronic myeloid leukemia (CML) is relevant to the development of biologically based risk models of radiation-induced CML. Through a comparison of the age structure of CML incidence data from the Surveillance, Epidemiology, and End Results (SEER) Program and the age structure of chromosomal translocations found in healthy subjects, the number of CML target stem cells is estimated for individuals above 20 years of age. The estimation involves three steps. First, CML incidence among adults is fit to an exponentially increasing function of age. Next, assuming a relatively short waiting time distribution between BCR-ABL induction and the appearance of CML, an exponential age function with rate constants fixed to the values found for CML is fitted to the translocation data. Finally, assuming that translocations are equally likely to occur between any two points in the genome, the parameter estimates found in the first two steps are used to estimate the number of target stem cells for CML. The population-averaged estimates of this number are found to be 1.86 x 10 8 for men and 1.21 x 10 8 for women; the 95% confidence intervals of these estimates are (1.34 x 10 8 , 2.50 x 10 8 ) and (0.84 x 10 8 , 1.83 x 10 8 ), respectively. (orig.)

Inhibition of histone deacetylases 1 and 6 enhances cytarabine-induced apoptosis in pediatric acute myeloid leukemia cells.

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Xuelian Xu

Full Text Available BACKGROUND: Pediatric acute myeloid leukemia (AML remains a challenging disease to treat even with intensified cytarabine-based chemotherapy. Histone deacetylases (HDACs have been reported to be promising therapeutic targets for treating AML. However, HDAC family members that are involved in chemotherapy sensitivities remain unknown. In this study, we sought to identify members of the HDAC family that are involved in cytarabine sensitivities, and to select the optimal HDACI that is most efficacious when combined with cytarabine for treating children with AML. METHODOLOGY: Expression profiles of classes I, II, and IV HDACs in 4 pediatric AML cell lines were determined by Western blotting. Inhibition of class I HDACs by different HDACIs was measured post immnunoprecipitation. Individual down-regulation of HDACs in pediatric AML cells was performed with lentiviral shRNA. The effects of cytarabine and HDACIs on apoptosis were determined by flow cytometry analysis. RESULTS: Treatments with structurally diverse HDACIs and HDAC shRNA knockdown experiments revealed that down-regulation of both HDACs 1 and 6 is critical in enhancing cytarabine-induced apoptosis in pediatric AML, at least partly mediated by Bim. However, down-regulation of HDAC2 may negatively impact cytarabine sensitivities in the disease. At clinically achievable concentrations, HDACIs that simultaneously inhibited both HDACs 1 and 6 showed the best anti-leukemic activities and significantly enhanced cytarabine-induced apoptosis. CONCLUSION: Our results further confirm that HDACs are bona fide therapeutic targets for treating pediatric AML and suggest that pan-HDACIs may be more beneficial than isoform-specific drugs.

The expression of B7-H1 and B7-H4 molecules on immature myeloid and lymphoid dendritic cells in cord blood of healthy neonates.

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S Radej

2011-04-01

Full Text Available The aim of our study was to estimate both B7-H1 and B7-H4 molecules on immature myeloid and lymphoid dendritic cells in umbilical cord blood of healthy neonates in comparison with peripheral blood of healthy adults. Thirty nine healthy full-term neonates from physiological single pregnancies and 27 healthy adults were included in the study. The expression of B7-H1 and B7-H4 was revealed using the immunofluorescence method. Statistical analysis was performed using a non-parametric test (Mann-Whitney U-Test. The percentages of BDCA-1+ dendritic cells with B7-H1 and B7-H4 expressions were significantly higher in peripheral blood of healthy adults (p<0.00003. It was either observed that the percentage of BDCA-2+ dendritic cells with the expression of B7-H4 molecules was significantly higher in peripheral blood of healthy adults in comparison with umbilical cord blood (p<0.02. Decreased percentages of dendritic cells and co-stimulatory molecules indicate that neonates have immature immune system. Depletion of co-stimulatory B7-H1 and B7-H4 molecules enable appropriate development of immune response.

Impact of postremission consolidation chemotherapy on outcome after reduced-intensity conditioning allogeneic stem cell transplantation for patients with acute myeloid leukemia in first complete remission

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Yeshurun, Moshe; Labopin, Myriam; Blaise, Didier

2014-01-01

The objective of the current study was to investigate the role of postremission consolidation chemotherapy before reduced-intensity conditioning (RIC) allogeneic stem cell transplantation (alloSCT) for patients with acute myeloid leukemia (AML) in first complete remission (CR1)....

Classification of acute myeloid leukemia subtypes M1, M2 and M3 using active contour without edge segmentation and momentum backpropagation artificial neural network

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Harjoko Agus

2018-01-01

Full Text Available Acute Myeloid Leukemia (AML is a type of cancer which attacks white blood cells from myeloid. AML has eight subtypes, namely: M0, M1, M2, M3, M4, M5, M6, and M7. AML subtypes M1, M2 and M3 are affected by the same type of cells, myeloblast, making it needs more detailed analysis to distinguish. To overcome these obstacles, this research is applying digital image processing with Active Contour Without Edge (ACWE and Momentum Backpropagation artificial neural network for AML subtypes M1, M2 and M3 classification based on the type of the cell. Six features required as training parameters from every cell obtained by using feature extraction. The features are: cell area, perimeter, circularity, nucleus ratio, mean and standard deviation. The results show that ACWE can be used for segmenting white blood cells with 83.789% success percentage of 876 total cell objects. The whole AML slides had been identified according to the cell types predicted number through training with momentum backpropagation. Five times testing calibration with the best parameter generated averages value of 84.754% precision, 75.887% sensitivity, 95.090% specificity and 93.569% accuracy.

Apoptosis in chronic myeloid leukaemia: normal responses by progenitor cells to growth factor deprivation, X-irradiation and glucocorticoids

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Amos, T.A.S.; Lewis, J.L.; Grand, F.H.; Gooding, R.P.; Goldman, J.M.; Gordon, M.Y. [Royal Postgraduate Medical School, London (United Kingdom)

1995-10-01

Inhibition of apoptosis (genetically programmed active cell death) by p210 BCR-ABL expression is a mechanism that might contribute to clonal expansion in chronic myeloid leukaemia (CML). Since cell death following exposure to ionizing radiation and many chemotherapeutic agents can occur by the apoptotic pathway, inhibition of apoptosis would be expected to confer a relative resistance to these treatments. Similarly, cells deprived of growth factors in vitro die by apoptosis, and inhibition of apoptosis would therefore be expected to allow cells to survive better in growth factor-deprived conditions. We found that the survival of normal and CML myeloid progenitors was the same after in vitro incubation in deprived conditions and after treatment with X-irradiation or glucocorticoids. We also found that mature cells in colonies produced by CML progenitors (CFU-GM) did not survive better than those produced by normal progenitor cells. Flow cytometric analysis of propidium iodide-stained cells provided a direct indication that the degree of apoptosis may correspond to the degree of deprivation. These results suggest that inhibition of apoptosis may not be the primary mechanism whereby BCR-ABL influences the expansion of the malignant clone in CML. (Author).

Apoptosis in chronic myeloid leukaemia: normal responses by progenitor cells to growth factor deprivation, X-irradiation and glucocorticoids

International Nuclear Information System (INIS)

Amos, T.A.S.; Lewis, J.L.; Grand, F.H.; Gooding, R.P.; Goldman, J.M.; Gordon, M.Y.

1995-01-01

Inhibition of apoptosis (genetically programmed active cell death) by p210 BCR-ABL expression is a mechanism that might contribute to clonal expansion in chronic myeloid leukaemia (CML). Since cell death following exposure to ionizing radiation and many chemotherapeutic agents can occur by the apoptotic pathway, inhibition of apoptosis would be expected to confer a relative resistance to these treatments. Similarly, cells deprived of growth factors in vitro die by apoptosis, and inhibition of apoptosis would therefore be expected to allow cells to survive better in growth factor-deprived conditions. We found that the survival of normal and CML myeloid progenitors was the same after in vitro incubation in deprived conditions and after treatment with X-irradiation or glucocorticoids. We also found that mature cells in colonies produced by CML progenitors (CFU-GM) did not survive better than those produced by normal progenitor cells. Flow cytometric analysis of propidium iodide-stained cells provided a direct indication that the degree of apoptosis may correspond to the degree of deprivation. These results suggest that inhibition of apoptosis may not be the primary mechanism whereby BCR-ABL influences the expansion of the malignant clone in CML. (Author)

Stage-Specific Human Induced Pluripotent Stem Cells Map the Progression of Myeloid Transformation to Transplantable Leukemia.

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Kotini, Andriana G; Chang, Chan-Jung; Chow, Arthur; Yuan, Han; Ho, Tzu-Chieh; Wang, Tiansu; Vora, Shailee; Solovyov, Alexander; Husser, Chrystel; Olszewska, Malgorzata; Teruya-Feldstein, Julie; Perumal, Deepak; Klimek, Virginia M; Spyridonidis, Alexandros; Rampal, Raajit K; Silverman, Lewis; Reddy, E Premkumar; Papaemmanuil, Elli; Parekh, Samir; Greenbaum, Benjamin D; Leslie, Christina S; Kharas, Michael G; Papapetrou, Eirini P

2017-03-02

Myeloid malignancy is increasingly viewed as a disease spectrum, comprising hematopoietic disorders that extend across a phenotypic continuum ranging from clonal hematopoiesis to myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). In this study, we derived a collection of induced pluripotent stem cell (iPSC) lines capturing a range of disease stages encompassing preleukemia, low-risk MDS, high-risk MDS, and secondary AML. Upon their differentiation, we found hematopoietic phenotypes of graded severity and/or stage specificity that together delineate a phenotypic roadmap of disease progression culminating in serially transplantable leukemia. We also show that disease stage transitions, both reversal and progression, can be modeled in this system using genetic correction or introduction of mutations via CRISPR/Cas9 and that this iPSC-based approach can be used to uncover disease-stage-specific responses to drugs. Our study therefore provides insight into the cellular events demarcating the initiation and progression of myeloid transformation and a new platform for testing genetic and pharmacological interventions. Copyright © 2017 Elsevier Inc. All rights reserved.

Myeloid-derived suppressor cells mediate immune suppression in spinal cord injury.

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Wang, Lei; Yu, Wei-bo; Tao, Lian-yuan; Xu, Qing

2016-01-15

Spinal cord injury (SCI) is characterized by the loss of motor and sensory functions in areas below the level of the lesion and numerous accompanying deficits. Previous studies have suggested that myeloid-derived suppressor cell (MDSC)-induced immune depression may play a pivotal role in the course of SCI. However, the concrete mechanism of these changes regarding immune suppression remains unknown. Here, we created an SCI mouse model to gain further evidence regarding the relationship between MDSCs following SCI and T lymphocyte suppression. We showed that in the SCI mouse model, the expanding MDSCs have the capacity to suppress T cell proliferation, and this suppression could be reversed by blocking the arginase. Copyright © 2015 Elsevier B.V. All rights reserved.

Andrographolide potentiates the antitumor effect of topotecan in acute myeloid leukemia cells through an intrinsic apoptotic pathway

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Hodroj MH

2018-05-01

Full Text Available Mohammad Hassan Hodroj, Achraf Jardaly, Sarah Abi Raad, Annalise Zouein, Sandra Rizk Department of Natural Sciences, Lebanese American University, Beirut, Lebanon Background: Topotecan (TP is an anticancer drug acting as topoisomerase I inhibitor that is used in the treatment of many types of cancers including leukemia, but it has significant side effects. Andrographolide, a compound extracted from Andrographis paniculata, was recently proven to inhibit the growth of cancer cells and can induce apoptosis. The aim of this study is to investigate the possible synergism between TP and andrographolide in acute myeloid cells in vitro. Materials and methods: U937 acute myeloid leukemic cells were cultured using Roswell Park Memorial Institute (RPMI medium and then treated for 24 h with TP and andrographolide prepared through the dilution of dimethyl sulfoxide (DMSO stocks with RPMI on the day of treatment. Cell proliferation was assessed using cell proliferation assay upon treatment with both compounds separately and in combination. Cell-cycle study and apoptosis detection were performed by staining the cells with propidium iodide (PI stain and Annexin V/PI stain, respectively, followed by flow cytometry analysis. Western blotting was used to assess the expression of various proteins involved in apoptotic pathways. Results: Both TP and andrographolide showed an antiproliferative effect in a dose-dependent manner when applied on U937 cells separately; however, pretreating the cells with andrographolide before applying TP exhibited a synergistic effect with lower inhibitory concentrations (half-maximal inhibitory concentration. Treating the cells with TP alone led to specific cell-cycle arrest at S phase that was more prominent upon pretreatment combination with andrographolide. Using Annexin V/PI staining to assess the proapoptotic effect following the pretreatment combination showed an increase in the number of apoptotic cells, which was supported by

Conservation of myeloid surface antigens on primate granulocytes.

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Letvin, N L; Todd, R F; Palley, L S; Schlossman, S F; Griffin, J D

1983-02-01

Monoclonal antibodies reactive with myeloid cell surface antigens were used to study evolutionary changes in granulocyte surface antigens from primate species. Certain of these granulocyte membrane antigens are conserved in phylogenetically distant species, indicating the potential functional importance of these structures. The degree of conservation of these antigens reflects the phylogenetic relationship between primate species. Furthermore, species of the same genus show similar patterns of binding to this panel of anti-human myeloid antibodies. This finding of conserved granulocyte surface antigens suggests that non-human primates may provide a model system for exploring uses of monoclonal antibodies in the treatment of human myeloid disorders.

Genetics Home Reference: core binding factor acute myeloid leukemia

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... binding factor acute myeloid leukemia Core binding factor acute myeloid leukemia Printable PDF Open All Close All Enable Javascript ... on PubMed (1 link) PubMed OMIM (1 link) LEUKEMIA, ACUTE MYELOID Sources for This Page Goyama S, Mulloy JC. Molecular ...

Characterization of the myeloid-derived suppressor cell subset regulated by NK cells in malignant lymphoma.

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Sato, Yusuke; Shimizu, Kanako; Shinga, Jun; Hidaka, Michihiro; Kawano, Fumio; Kakimi, Kazuhiro; Yamasaki, Satoru; Asakura, Miki; Fujii, Shin-Ichiro

2015-03-01

Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population with the ability to suppress immune responses and are currently classified into three distinct MDSC subsets: monocytic, granulocytic and non-monocytic, and non-granulocytic MDSCs. Although NK cells provide an important first-line defense against newly transformed cancer cells, it is unknown whether NK cells can regulate MDSC populations in the context of cancer. In this study, we initially found that the frequency of MDSCs in non-Hodgkin lymphoma (NHL) patients was increased and inversely correlated with that of NK cells, but not that of T cells. To investigate the regulation of MDSC subsets by NK cells, we used an EL4 murine lymphoma model and found the non-monocytic and non-granulocytic MDSC subset, i.e., Gr1 + CD11b + Ly6G med Ly6C med MDSC, is increased after NK cell depletion. The MDSC population that expresses MHC class II, CD80, CD124, and CCR2 is regulated mainly by CD27 + CD11b + NK cells. In addition, this MDSC subset produces some immunosuppressive cytokines, including IL-10 but not nitric oxide (NO) or arginase. We also examined two subsets of MDSCs (CD14 + HLA-DR - and CD14 - HLA-DR - MDSC) in NHL patients and found that higher IL-10-producing CD14 + HLA-DR - MDSC subset can be seen in lymphoma patients with reduced NK cell frequency in peripheral blood. Our analyses of MDSCs in this study may enable a better understanding of how MDSCs manipulate the tumor microenvironment and are regulated by NK cells in patients with lymphoma.

Wnt/β-catenin pathway regulates ABCB1 transcription in chronic myeloid leukemia

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Corrêa, Stephany; Binato, Renata; Du Rocher, Bárbara; Castelo-Branco, Morgana TL; Pizzatti, Luciana; Abdelhay, Eliana

2012-01-01

The advanced phases of chronic myeloid leukemia (CML) are known to be more resistant to therapy. This resistance has been associated with the overexpression of ABCB1, which gives rise to the multidrug resistance (MDR) phenomenon. MDR is characterized by resistance to nonrelated drugs, and P-glycoprotein (encoded by ABCB1) has been implicated as the major cause of its emergence. Wnt signaling has been demonstrated to be important in several aspects of CML. Recently, Wnt signaling was linked to ABCB1 regulation through its canonical pathway, which is mediated by β-catenin, in other types of cancer. In this study, we investigated the involvement of the Wnt/β-catenin pathway in the regulation of ABCB1 transcription in CML, as the basal promoter of ABCB1 has several β-catenin binding sites. β-catenin is the mediator of canonical Wnt signaling, which is important for CML progression. In this work we used the K562 cell line and its derived MDR-resistant cell line Lucena (K562/VCR) as CML study models. Real time PCR (RT-qPCR), electrophoretic mobility shift assay (EMSA), chromatin immunoprecipitation (ChIP), flow cytometry (FACS), western blot, immunofluorescence, RNA knockdown (siRNA) and Luciferase reporter approaches were used. β-catenin was present in the protein complex on the basal promoter of ABCB1 in both cell lines in vitro, but its binding was more pronounced in the resistant cell line in vivo. Lucena cells also exhibited higher β-catenin levels compared to its parental cell line. Wnt1 and β-catenin depletion and overexpression of nuclear β-catenin, together with TCF binding sites activation demonstrated that ABCB1 is positively regulated by the canonical pathway of Wnt signaling. These results suggest, for the first time, that the Wnt/β-catenin pathway regulates ABCB1 in CML

The farnesoid-X-receptor in myeloid cells controls CNS autoimmunity in an IL-10-dependent fashion.

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Hucke, Stephanie; Herold, Martin; Liebmann, Marie; Freise, Nicole; Lindner, Maren; Fleck, Ann-Katrin; Zenker, Stefanie; Thiebes, Stephanie; Fernandez-Orth, Juncal; Buck, Dorothea; Luessi, Felix; Meuth, Sven G; Zipp, Frauke; Hemmer, Bernhard; Engel, Daniel Robert; Roth, Johannes; Kuhlmann, Tanja; Wiendl, Heinz; Klotz, Luisa

2016-09-01

Innate immune responses by myeloid cells decisively contribute to perpetuation of central nervous system (CNS) autoimmunity and their pharmacologic modulation represents a promising strategy to prevent disease progression in Multiple Sclerosis (MS). Based on our observation that peripheral immune cells from relapsing-remitting and primary progressive MS patients exhibited strongly decreased levels of the bile acid receptor FXR (farnesoid-X-receptor, NR1H4), we evaluated its potential relevance as therapeutic target for control of established CNS autoimmunity. Pharmacological FXR activation promoted generation of anti-inflammatory macrophages characterized by arginase-1, increased IL-10 production, and suppression of T cell responses. In mice, FXR activation ameliorated CNS autoimmunity in an IL-10-dependent fashion and even suppressed advanced clinical disease upon therapeutic administration. In analogy to rodents, pharmacological FXR activation in human monocytes from healthy controls and MS patients induced an anti-inflammatory phenotype with suppressive properties including control of effector T cell proliferation. We therefore, propose an important role of FXR in control of T cell-mediated autoimmunity by promoting anti-inflammatory macrophage responses.

Pre-apoptotic response to therapeutic DNA damage involves protein modulation of Mcl-1, Hdm2 and Flt3 in acute myeloid leukemia cells

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Hovland Randi

2007-05-01

Full Text Available Abstract Background Acute myeloid leukemia (AML cells are characterized by non-mutated TP53, high levels of Hdm2, and frequent mutation of the Flt3 receptor tyrosine kinase. The juxtamembrane mutation of FLT3 is the strongest independent marker for disease relapse and is associated with elevated Bcl-2 protein and p53 hyper-phosphorylation in AML. DNA damage forms the basic mechanism of cancer cell eradication in current therapy of AML. Hdm2 and pro-apoptotic Bcl-2 members are among the most intensely induced genes immediately after chemotherapy and Hdm2 is proposed a role in receptor tyrosine kinase regulation. Thus we examined the DNA damage related modulation of these proteins in relation to FLT3 mutational status and induction of apoptosis. Results Within one hour after exposure to ionizing radiation (IR, the AML cells (NB4, MV4-11, HL-60, primary AML cells showed an increase in Flt3 protein independent of mRNA levels, while the Hdm2 protein decreased. The FLT3 mutant MV4-11 cells were resistant to IR accompanied by presence of both Mcl-1 and Hdm2 protein three hours after IR. In contrast, the FLT3 wild type NB4 cells responded to IR with apoptosis and pre-apoptotic Mcl-1 down regulation. Daunorubicin (DNR induced continuing down regulation of Hdm2 and Mcl-1 in both cell lines followed by apoptosis. Conclusion Both IR and DNR treatment resulted in concerted protein modulations of Mcl-1, Hdm2 and Flt3. Cell death induction was associated with persistent attenuation of Mcl-1 and Hdm2. These observations suggest that defining the pathway(s modulating Flt3, Hdm2 and Mcl-1 may propose new strategies to optimize therapy for the relapse prone FLT3 mutated AML patients.

Single-cell transcriptomics uncovers distinct molecular signatures of stem cells in chronic myeloid leukemia.

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Giustacchini, Alice; Thongjuea, Supat; Barkas, Nikolaos; Woll, Petter S; Povinelli, Benjamin J; Booth, Christopher A G; Sopp, Paul; Norfo, Ruggiero; Rodriguez-Meira, Alba; Ashley, Neil; Jamieson, Lauren; Vyas, Paresh; Anderson, Kristina; Segerstolpe, Åsa; Qian, Hong; Olsson-Strömberg, Ulla; Mustjoki, Satu; Sandberg, Rickard; Jacobsen, Sten Eirik W; Mead, Adam J

2017-06-01

Recent advances in single-cell transcriptomics are ideally placed to unravel intratumoral heterogeneity and selective resistance of cancer stem cell (SC) subpopulations to molecularly targeted cancer therapies. However, current single-cell RNA-sequencing approaches lack the sensitivity required to reliably detect somatic mutations. We developed a method that combines high-sensitivity mutation detection with whole-transcriptome analysis of the same single cell. We applied this technique to analyze more than 2,000 SCs from patients with chronic myeloid leukemia (CML) throughout the disease course, revealing heterogeneity of CML-SCs, including the identification of a subgroup of CML-SCs with a distinct molecular signature that selectively persisted during prolonged therapy. Analysis of nonleukemic SCs from patients with CML also provided new insights into cell-extrinsic disruption of hematopoiesis in CML associated with clinical outcome. Furthermore, we used this single-cell approach to identify a blast-crisis-specific SC population, which was also present in a subclone of CML-SCs during the chronic phase in a patient who subsequently developed blast crisis. This approach, which might be broadly applied to any malignancy, illustrates how single-cell analysis can identify subpopulations of therapy-resistant SCs that are not apparent through cell-population analysis.

A stratified myeloid system, the challenge of understanding macrophage diversity.

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Geissmann, F; Mass, E

2015-12-01

The present issue of 'Seminars in Immunology' addresses the topic of macrophage biology, 100 years after the death of Elie Metchnikoff (May 1845-July 1916). As foreseen by Metchnikoff, the roles of macrophages in the maintenance of homeostasis and immunity against pathogens have become a broad and active area of investigation. We now start to realize that the myeloid system includes a multiplicity of cell types with diverse developmental origins and functions. Therefore, the textbook picture of a plastic and multifunctional macrophage does not meet the requirements of our current knowledge anymore. Further development toward a quantitative and molecular understanding of myeloid cell biology in vivo and their roles in tissue homeostasis and remodeling will benefit from taking this complexity into account. A tentative model to help in this pursuit and account for myeloid cell and macrophage diversity is discussed below. Copyright © 2016. Published by Elsevier Ltd.

Calreticulin Fragment 39-272 Promotes B16 Melanoma Malignancy through Myeloid-Derived Suppressor Cells In Vivo

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Xiao-Yan He

2017-10-01

Full Text Available Calreticulin (CRT, a multifunctional Ca2+-binding glycoprotein mainly located in the endoplasmic reticulum, is a tumor-associated antigen that has been shown to play protective roles in angiogenesis suppression and anti-tumor immunity. We previously reported that soluble CRT (sCRT was functionally similar to heat shock proteins or damage-associated molecular patterns in terms of ability to activate myeloid cells and elicit strong inflammatory cytokine production. In the present study, B16 melanoma cell lines expressing recombinant CRT fragment 39-272 (sCRT/39-272 in secreted form (B16-CRT, or recombinant enhanced green fluorescence protein (rEGFP (B16-EGFP, were constructed for investigation on the roles of sCRT in tumor development. When s.c. inoculated into C57BL/6 mice, the B16-CRT cells were significantly more aggressive (in terms of solid tumor growth rate than B16-EGFP controls in a TLR4- and myeloid-derived suppressor cells (MDSC-dependent manner. The B16-CRT-bearing mice showed increased Gr1+ MDSC infiltration in tumor tissues, accelerated proliferation of CD11b+Ly6G+Ly6Clow (G-MDSC precursors in bone marrow, and higher percentages of G-MDSCs in spleen and blood, which was mirrored by decreased percentage of dendritic cells (DC in periphery. In in vitro studies, recombinant sCRT/39-272 was able to promote migration and survival of tumor-derived MDSCs via interaction with TLR4, inhibit MDSC differentiation into DC, and also elicit expression of inflammatory proteins S100A8 and S100A9 which are essential for functional maturation and chemotactic migration of MDSCs. Our data provide solid evidence for CRT as a double-edged sword in tumor development.

The +37 kb Cebpa Enhancer Is Critical for Cebpa Myeloid Gene Expression and Contains Functional Sites that Bind SCL, GATA2, C/EBPα, PU.1, and Additional Ets Factors

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Cooper, Stacy; Guo, Hong; Friedman, Alan D.

2015-01-01

The murine Cebpa gene contains an evolutionarily conserved 453 bp enhancer located at +37 kb that, together with its promoter, directs expression to myeloid progenitors and to long-term hematopoietic stem cells in transgenic mice. In human acute myeloid leukemia cases, the enhancer lacks point mutations but binds the RUNX1-ETO oncoprotein. The enhancer contains the H3K4me1 and H3K27Ac histone modifications, denoting an active enhancer, at progressively increasing levels as long-term hematopoietic stem cells transition to granulocyte-monocyte progenitors. We previously identified four enhancer sites that bind RUNX1 and demonstrated that their integrity is required for maximal enhancer activity in 32Dcl3 myeloid cells. The +37 kb Cebpa enhancer also contains C/EBP, Ets factor, Myb, GATA, and E-box consensus sites conserved in the human +42 kb CEBPA enhancer. Mutation of the two C/EBP, seven Ets, one Myb, two GATA, or two E-box sites reduces activity of an enhancer-promoter reporter in 32Dcl3 cells. In 293T gel shift assays, exogenous C/EBPα binds both C/EBP sites, c-Myb binds the Myb site, PU.1 binds the second Ets site, PU.1, Fli-1, ERG, and Ets1 bind the sixth Ets site, GATA2 binds both GATA sites, and SCL binds the second E-box. Endogenous hematopoietic RUNX1, PU.1, Fli-1, ERG, C/EBPα, GATA2, and SCL were previously shown to bind the enhancer, and we find that endogenous PU.1 binds the second Ets site in 32Dcl3 cells. Using CRISPR/Cas9, we developed 32Dcl3 lines in which the wild-type enhancer alleles are replaced with a variant mutant in the seven Ets sites. These lines have 20-fold reduced Cebpa mRNA when cultured in IL-3 or G-CSF, demonstrating a critical requirement for enhancer integrity for optimal Cebpa expression. In addition, these results indicate that the +37 kb Cebpa enhancer is the focus of multiple regulatory transcriptional pathways that impact its expression during normal hematopoiesis and potentially during myeloid transformation. PMID:25938608

Clinical Impact of the Immunome in Lymphoid Malignancies: The Role of Myeloid-Derived Suppressor Cells

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Vetro, Calogero; Romano, Alessandra; Ancora, Flavia; Coppolino, Francesco; Brundo, Maria V.; Raccuia, Salvatore A.; Puglisi, Fabrizio; Tibullo, Daniele; La Cava, Piera; Giallongo, Cesarina; Parrinello, Nunziatina L.

2015-01-01

The better definition of the mutual sustainment between neoplastic cells and immune system has been translated from the bench to the bedside acquiring value as prognostic factor. Additionally, it represents a promising tool for improving therapeutic strategies. In this context, myeloid-derived suppressor cells (MDSCs) have gained a central role in tumor developing with consequent therapeutic implications. In this review, we will focus on the biological and clinical impact of the study of MDSCs in the settings of lymphoid malignancies. PMID:26052505

Epigenetics targeted protein-vorinostat nanomedicine inducing apoptosis in heterogeneous population of primary acute myeloid leukemia cells including refractory and relapsed cases.

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Chandran, Parwathy; Kavalakatt, Anu; Malarvizhi, Giridharan Loghanathan; Vasanthakumari, Divya Rani Vikraman Nair; Retnakumari, Archana Payickattu; Sidharthan, Neeraj; Pavithran, Keechilat; Nair, Shantikumar; Koyakutty, Manzoor

2014-05-01

Aberrant epigenetics play a key role in the onset and progression of acute myeloid leukemia (AML). Herein we report in silico modelling based development of a novel, protein-vorinostat nanomedicine exhibiting selective and superior anti-leukemic activity against heterogeneous population of AML patient samples (n=9), including refractory and relapsed cases, and three representative cell lines expressing CD34(+)/CD38(-) stem cell phenotype (KG-1a), promyelocytic phenotype (HL-60) and FLT3-ITD mutation (MV4-11). Nano-vorinostat having ~100nm size exhibited enhanced cellular uptake rendering significantly lower IC50 in AML cell lines and patient samples, and induced enhanced HDAC inhibition, oxidative injury, cell cycle arrest and apoptosis compared to free vorinostat. Most importantly, nanomedicine showed exceptional single-agent activity against the clonogenic proliferative capability of bone marrow derived leukemic progenitors, while remaining non-toxic to healthy bone marrow cells. Collectively, this epigenetics targeted nanomedicine appears to be a promising therapeutic strategy against various French-American-British (FAB) classes of AML. Through the use of a protein-vorinostat agent, exceptional single-agent activity was demonstrated against the clonogenic proliferative capability of bone marrow derived leukemic progenitors, while remaining non-toxic to healthy bone marrow cells. The studied epigenetics targeted nanomedicine approach is a promising therapeutic strategy against various French-American-British classes of acute myeloid leukemia. © 2014 Elsevier Inc. All rights reserved.

Azacitidine augments expansion of regulatory T cells after allogeneic stem cell transplantation in patients with acute myeloid leukemia (AML).

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Goodyear, Oliver C; Dennis, Mike; Jilani, Nadira Y; Loke, Justin; Siddique, Shamyla; Ryan, Gordon; Nunnick, Jane; Khanum, Rahela; Raghavan, Manoj; Cook, Mark; Snowden, John A; Griffiths, Mike; Russell, Nigel; Yin, John; Crawley, Charles; Cook, Gordon; Vyas, Paresh; Moss, Paul; Malladi, Ram; Craddock, Charles F

2012-04-05

Strategies that augment a GVL effect without increasing the risk of GVHD are required to improve the outcome after allogeneic stem cell transplantation (SCT). Azacitidine (AZA) up-regulates the expression of tumor Ags on leukemic blasts in vitro and expands the numbers of immunomodulatory T regulatory cells (Tregs) in animal models. Reasoning that AZA might selectively augment a GVL effect, we studied the immunologic sequelae of AZA administration after allogeneic SCT. Twenty-seven patients who had undergone a reduced intensity allogeneic transplantation for acute myeloid leukemia were treated with monthly courses of AZA, and CD8(+) T-cell responses to candidate tumor Ags and circulating Tregs were measured. AZA after transplantation was well tolerated, and its administration was associated with a low incidence of GVHD. Administration of AZA increased the number of Tregs within the first 3 months after transplantation compared with a control population (P = .0127). AZA administration also induced a cytotoxic CD8(+) T-cell response to several tumor Ags, including melanoma-associated Ag 1, B melanoma antigen 1, and Wilm tumor Ag 1. These data support the further examination of AZA after transplantation as a mechanism of augmenting a GVL effect without a concomitant increase in GVHD.

Allium compounds, dipropyl and dimethyl thiosulfinates as antiproliferative and differentiating agents of human acute myeloid leukemia cell lines

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Faten Merhi

2008-08-01

Full Text Available Faten Merhi1, Jacques Auger2, Francine Rendu1, Brigitte Bauvois11UMR 7131 UPMC Paris Universitas/CNRS, Groupe Hospitalier Broussais-HEGP, Paris, France; 2University F. Rabelais, IRBI, UPRESA CNRS 6035, Tours, FranceAbstract: Epidemiologic studies support the premise that Allium vegetables may lower the risk of cancers. The beneficial effects appear related to the organosulfur products generated upon processing of Allium. Leukemia cells from patients with acute myeloid leukemia (AML display high proliferative capacity and have a reduced capacity of undergoing apoptosis and maturation. Whether the sulfur-containing molecules thiosulfinates (TS, diallyl TS (All2TS, dipropyl TS (Pr2TS and dimethyl TS (Me2TS, are able to exert chemopreventative activity against AML is presently unknown. The present study was an evaluation of proliferation, cytotoxicity, differentiation and secretion of AML cell lines (U937, NB4, HL-60, MonoMac-6 in response to treatment with these TS and their related sulfides (diallylsulfide, diallyl disulfide, dipropyl disulfide, dimethyl disulfide. As assessed by flow cytometry, ELISA, gelatin zymogaphy and RT-PCR, we showed that Pr2TS and Me2TS, but not All2TS and sulfides, 1 inhibited cell proliferation in dose- and time-dependent manner and this process was neither due to cytotoxicity nor apoptosis, 2 induced macrophage maturation, and 3 inhibited the levels of secreted MMP-9 (protein and activity and TNF-α protein, without altering mRNA levels. By establishing for the first time that Pr2TS and Me2TS affect proliferation, differentiation and secretion of leukemic cell lines, this study provides the opportunity to explore the potential efficiency of these molecules in AML.Keywords: acute myeloid leukemia, thiosulfinate, proliferation, differentiation, matrix metalloproteinase-9

Therapies for acute myeloid leukemia: vosaroxin

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Sayar H

2017-08-01

Full Text Available Hamid Sayar,1 Parvaneh Bashardoust2 1Indiana University Simon Cancer Center, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, USA; 2Oceania University of Medicine, OUM-North America, Indianapolis, IN, USA Abstract: Vosaroxin, a quinolone-derivative chemotherapeutic agent, was considered a promising drug for the treatment of acute myeloid leukemia (AML. Early-stage clinical trials with this agent led to a large randomized double-blind placebo-controlled study of vosaroxin in combination with intermediate-dose cytarabine for the treatment of relapsed or refractory AML. The study demonstrated better complete remission rates with vosaroxin, but there was no statistically significant overall survival benefit in the whole cohort. A subset analysis censoring patients who had undergone allogeneic stem cell transplantation, however, revealed a modest but statistically significant improvement in overall survival particularly among older patients. This article reviews the data available on vosaroxin including clinical trials in AML and offers an analysis of findings of these studies as well as the current status of vosaroxin. Keywords: AML, acute myeloid leukemia, vosaroxin, SNS-595, cytarabine

ZFX Controls Propagation and Prevents Differentiation of Acute T-Lymphoblastic and Myeloid Leukemia

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Stuart P. Weisberg

2014-02-01

Full Text Available Tumor-propagating cells in acute leukemia maintain a stem/progenitor-like immature phenotype and proliferative capacity. Acute myeloid leukemia (AML and acute T-lymphoblastic leukemia (T-ALL originate from different lineages through distinct oncogenic events such as MLL fusions and Notch signaling, respectively. We found that Zfx, a transcription factor that controls hematopoietic stem cell self-renewal, controls the initiation and maintenance of AML caused by MLL-AF9 fusion and of T-ALL caused by Notch1 activation. In both leukemia types, Zfx prevents differentiation and activates gene sets characteristic of immature cells of the respective lineages. In addition, endogenous Zfx contributes to gene induction and transformation by Myc overexpression in myeloid progenitors. Key Zfx target genes include the mitochondrial enzymes Ptpmt1 and Idh2, whose overexpression partially rescues the propagation of Zfx-deficient AML. These results show that distinct leukemia types maintain their undifferentiated phenotype and self-renewal by exploiting a common stem-cell-related genetic regulator.

Quantitation of specific myeloid cells in rat bone marrow measured by in vitro /sup 35/S-sulphate incorporation

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Wright, A F; Rose, M S

1984-08-01

A biochemical measurement which can be used for quantitation of specific early myeloid cells in rat bone marrow has been developed. This measurement consists of a rapid, simple assay for the in vitro quantitation of /sup 35/S-sulfate incorporation into rat bone marrow cells. Incubation of bone marrow cells with /sup 35/S-sulfate led to a time-dependent increase in radioactivity obtained in perchloric acid insoluble fractions of bone marrow cell suspensions. This incorporation was inhibited by cyanide and puromycin. Autoradiography has demonstrated the radiolabel to be specifically associated with immature cells of the myeloid series. The cells most active in this respect were eosinophils. When rats were treated with endotoxin, the rate of /sup 35/S-sulfate incorporation was increased. Cell number measurements, using conventional histopathology and a Coulter Counter, demonstrated that endotoxin caused an initial release of mature granulocytes from the bone marrow. The regeneration of this mature population in the marrow was rapid, and was characterized by an increase in the number of immature cells and a concomitant increase in the rate of /sup 35/S-sulfate incorporation measured in preparations of bone marrow cells in vitro. Furthermore, this response to endotoxin has demonstrated that Coulter Counting techniques can be used to distinguish specific populations of cells (e.g. mature granulocytes) within the bone marrow.

SHIP1-expressing mesenchymal stem cells regulate hematopoietic stem cell homeostasis and lineage commitment during aging.

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Iyer, Sonia; Brooks, Robert; Gumbleton, Matthew; Kerr, William G

2015-05-01

Hematopoietic stem cell (HSC) self-renewal and lineage choice are subject to intrinsic control. However, this intrinsic regulation is also impacted by external cues provided by niche cells. There are multiple cellular components that participate in HSC support with the mesenchymal stem cell (MSC) playing a pivotal role. We had previously identified a role for SH2 domain-containing inositol 5'-phosphatase-1 (SHIP1) in HSC niche function through analysis of mice with germline or induced SHIP1 deficiency. In this study, we show that the HSC compartment expands significantly when aged in a niche that contains SHIP1-deficient MSC; however, this expanded HSC compartment exhibits a strong bias toward myeloid differentiation. In addition, we show that SHIP1 prevents chronic G-CSF production by the aging MSC compartment. These findings demonstrate that intracellular signaling by SHIP1 in MSC is critical for the control of HSC output and lineage commitment during aging. These studies increase our understanding of how myeloid bias occurs in aging and thus could have implications for the development of myeloproliferative disease in aging.

The expression of B7-H1 and B7-H4 molecules on immature myeloid and lymphoid dendritic cells in cord blood of healthy neonates

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Kludka-Sternik M

2010-04-01

Full Text Available The aim of our study was to estimate both B7-H1 and B7-H4 molecules on immature myeloid and lymphoid dendriticcells in umbilical cord blood of healthy neonates in comparison with peripheral blood of healthy adults. Thirty ninehealthy full-term neonates from physiological single pregnancies and 27 healthy adults were included in the study. Theexpression of B7-H1 and B7-H4 was revealed using the immunofluorescence method. Statistical analysis was performedusing a non-parametric test (Mann-Whitney U-Test. The percentages of BDCA-1+ dendritic cells with B7-H1 and B7-H4expressions were significantly higher in peripheral blood of healthy adults (p<0.00003. It was either observed that the percentageof BDCA-2+ dendritic cells with the expression of B7-H4 molecules was significantly higher in peripheral blood ofhealthy adults in comparison with umbilical cord blood (p<0.02. Decreased percentages of dendritic cells and co-stimulatorymolecules indicate that neonates have immature immune system. Depletion of co-stimulatory B7-H1 and B7-H4 moleculesenable appropriate development of immune response.

CHANGES OF BUOYANT DENSITY DURING THE S-PHASE OF THE CELL-CYCLE - DIRECT EVIDENCE DEMONSTRATED IN ACUTE MYELOID-LEUKEMIA BY FLOW-CYTOMETRIC

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DAENEN, S; HUIGES, W; MODDERMAN, E; HALIE, MR

Studies with synchronized or exponentially growing bacteria and mammalian cell lines are not able to demonstrate small changes in buoyant density during the cell cycle. Flowcytometric analysis of density separated acute myeloid leukemia cells, a system not dependent on time-related variables, shows

Combined Targeting of BCL-2 and BCR-ABL Tyrosine Kinase Eradicates Chronic Myeloid Leukemia Stem Cells

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Mak, Po Yee; Mu, Hong; Zhou, Hongsheng; Mak, Duncan H.; Schober, Wendy; Leverson, Joel D.; Zhang, Bin; Bhatia, Ravi; Huang, Xuelin; Cortes, Jorge; Kantarjian, Hagop; Konopleva, Marina

2016-01-01

BCR-ABL tyrosine kinase inhibitors (TKIs) are effective against chronic myeloid leukemia (CML), but they rarely eliminate CML stem cells. Disease relapse is common upon therapy cessation, even in patients with complete molecular responses. Furthermore, once CML progresses to blast crisis (BC), treatment outcomes are dismal. We hypothesized that concomitant targeting of BCL-2 and BCR-ABL tyrosine kinase could overcome these limitations. We demonstrate increased BCL-2 expression at the protein level in bone marrow cells, particularly in Lin−Sca-1+cKit+ cells of inducible CML in mice as determined by CyTOF mass cytometry. Further, selective inhibition of BCL-2, aided by TKI-mediated MCL-1 and BCL-XL inhibition, markedly decreased leukemic Lin−Sca-1+cKit+ cell numbers and long-term stem cell frequency, and prolonged survival in a murine CML model. Additionally, this combination effectively eradicated CD34+CD38−, CD34+CD38+, and quiescent stem/progenitor CD34+ cells from BC CML patient samples. Our results suggest that BCL-2 is a key survival factor for CML stem/progenitor cells and that combined inhibition of BCL-2 and BCR-ABL tyrosine kinase has the potential to significantly improve depth of response and cure rates of chronic phase and BC CML. PMID:27605552

Myeloid-derived suppressor cells express Bruton’s tyrosine kinase and can be depleted in tumor bearing hosts by ibrutinib treatment

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Stiff, Andrew; Trikha, Prashant; Wesolowski, Robert; Kendra, Kari; Hsu, Vincent; Uppati, Sarvani; McMichael, Elizabeth; Duggan, Megan; Campbell, Amanda; Keller, Karen; Landi, Ian; Zhong, Yiming; Dubovsky, Jason; Howard, John Harrison; Yu, Lianbo; Harrington, Bonnie; Old, Matthew; Reiff, Sean; Mace, Thomas; Tridandapani, Susheela; Muthusamy, Natarajan; Caligiuri, Michael A.; Byrd, John C.; Carson, William E.

2016-01-01

Myeloid-derived suppressor cells (MDSCs) are a heterogeneous group of immature myeloid cells that expand in tumor bearing hosts in response to soluble factors produced by tumor and stromal cells. MDSC expansion has been linked to loss of immune effector cell function and reduced efficacy of immune-based cancer therapies, highlighting the MDSC population as an attractive therapeutic target. Ibrutinib, an irreversible inhibitor of Bruton’s tyrosine kinase (BTK) and IL2-inducible T-cell kinase (ITK), is in clinical use for the treatment of B cell malignancies. Here, we report that BTK is expressed by murine and human MDSCs, and that ibrutinib is able to inhibit BTK phosphorylation in these cells. Treatment of MDSCs with ibrutinib significantly impaired nitric oxide production and cell migration. In addition, ibrutinib inhibited in vitro generation of human MDSCs and reduced mRNA expression of indolamine 2,3-dioxygenase, an immunosuppressive factor. Treatment of mice bearing EMT6 mammary tumors with ibrutinib resulted in reduced frequency of MDSCs in both the spleen and tumor. Ibrutinib treatment also resulted in a significant reduction of MDSCs in wildtype mice bearing B16F10 melanoma tumors, but not in X-linked immunodeficiency mice (XID) harboring a BTK mutation, suggesting that BTK inhibition plays an important role in the observed reduction of MDSCs in vivo. Finally, ibrutinib significantly enhanced the efficacy of anti-PD-L1 (CD274) therapy in a murine breast cancer model. Together, these results demonstrate that ibrutinib modulates MDSC function and generation, revealing a potential strategy for enhancing immune-based therapies in solid malignancies. PMID:26880800

Myeloid-Derived Suppressor Cells Express Bruton's Tyrosine Kinase and Can Be Depleted in Tumor-Bearing Hosts by Ibrutinib Treatment.

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Stiff, Andrew; Trikha, Prashant; Wesolowski, Robert; Kendra, Kari; Hsu, Vincent; Uppati, Sarvani; McMichael, Elizabeth; Duggan, Megan; Campbell, Amanda; Keller, Karen; Landi, Ian; Zhong, Yiming; Dubovsky, Jason; Howard, John Harrison; Yu, Lianbo; Harrington, Bonnie; Old, Matthew; Reiff, Sean; Mace, Thomas; Tridandapani, Susheela; Muthusamy, Natarajan; Caligiuri, Michael A; Byrd, John C; Carson, William E

2016-04-15

Myeloid-derived suppressor cells (MDSC) are a heterogeneous group of immature myeloid cells that expand in tumor-bearing hosts in response to soluble factors produced by tumor and stromal cells. MDSC expansion has been linked to loss of immune effector cell function and reduced efficacy of immune-based cancer therapies, highlighting the MDSC population as an attractive therapeutic target. Ibrutinib, an irreversible inhibitor of Bruton's tyrosine kinase (BTK) and IL2-inducible T-cell kinase (ITK), is in clinical use for the treatment of B-cell malignancies. Here, we report that BTK is expressed by murine and human MDSCs, and that ibrutinib is able to inhibit BTK phosphorylation in these cells. Treatment of MDSCs with ibrutinib significantly impaired nitric oxide production and cell migration. In addition, ibrutinib inhibited in vitro generation of human MDSCs and reduced mRNA expression of indolamine 2,3-dioxygenase, an immunosuppressive factor. Treatment of mice bearing EMT6 mammary tumors with ibrutinib resulted in reduced frequency of MDSCs in both the spleen and tumor. Ibrutinib treatment also resulted in a significant reduction of MDSCs in wild-type mice bearing B16F10 melanoma tumors, but not in X-linked immunodeficiency mice (XID) harboring a BTK mutation, suggesting that BTK inhibition plays an important role in the observed reduction of MDSCs in vivo Finally, ibrutinib significantly enhanced the efficacy of anti-PD-L1 (CD274) therapy in a murine breast cancer model. Together, these results demonstrate that ibrutinib modulates MDSC function and generation, revealing a potential strategy for enhancing immune-based therapies in solid malignancies. Cancer Res; 76(8); 2125-36. ©2016 AACR. ©2016 American Association for Cancer Research.

Effects on proliferation and cell cycle of irradiated KG-1 cells stimulated by CM-CSF

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Guo Dehuang; Dong Bo; Wen Gengyun; Luo Qingliang; Mao Bingzhi

2000-01-01

In order to explore the variety of cell proliferation and cell cycle after exposure to ionizing radiation, the responses of irradiated KG-1 cells of the human myeloid leukemia stimulated by GM-CSF, the most common used cytokine in clinic, were investigated. The results showed that GM-CSF enhance KG-1 cells proliferation, reduce G0/G1 block, increase S phase and G2/M phase. The stimulation effects of the GM-CSF are more effective in irradiated group than in control group

Transforming growth factor beta-activated kinase 1 (TAK1)-dependent checkpoint in the survival of dendritic cells promotes immune homeostasis and function.

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Wang, Yanyan; Huang, Gonghua; Vogel, Peter; Neale, Geoffrey; Reizis, Boris; Chi, Hongbo

2012-02-07

Homeostatic control of dendritic cell (DC) survival is crucial for adaptive immunity, but the molecular mechanism is not well defined. Moreover, how DCs influence immune homeostasis under steady state remains unclear. Combining DC-specific and -inducible deletion systems, we report that transforming growth factor beta-activated kinase 1 (TAK1) is an essential regulator of DC survival and immune system homeostasis and function. Deficiency of TAK1 in CD11c(+) cells induced markedly elevated apoptosis, leading to the depletion of DC populations, especially the CD8(+) and CD103(+) DC subsets in lymphoid and nonlymphoid tissues, respectively. TAK1 also contributed to DC development by promoting the generation of DC precursors. Prosurvival signals from Toll-like receptors, CD40 and receptor activator of nuclear factor-κB (RANK) are integrated by TAK1 in DCs, which in turn mediated activation of downstream NF-κB and AKT-Foxo pathways and established a gene-expression program. TAK1 deficiency in DCs caused a myeloid proliferative disorder characterized by expansion of neutrophils and inflammatory monocytes, disrupted T-cell homeostasis, and prevented effective T-cell priming and generation of regulatory T cells. Moreover, TAK1 signaling in DCs was required to prevent myeloid proliferation even in the absence of lymphocytes, indicating a previously unappreciated regulatory mechanism of DC-mediated control of myeloid cell-dependent inflammation. Therefore, TAK1 orchestrates a prosurvival checkpoint in DCs that affects the homeostasis and function of the immune system.

Circulating endothelial cells are increased in chronic myeloid leukemia blast crisis

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C.R.T. Godoy

2015-06-01

Full Text Available We measured circulating endothelial precursor cells (EPCs, activated circulating endothelial cells (aCECs, and mature circulating endothelial cells (mCECs using four-color multiparametric flow cytometry in the peripheral blood of 84 chronic myeloid leukemia (CML patients and 65 healthy controls; and vascular endothelial growth factor (VEGF by quantitative real-time PCR in 50 CML patients and 32 healthy controls. Because of an increase in mCECs, the median percentage of CECs in CML blast crisis (0.0146% was significantly higher than in healthy subjects (0.0059%, P0.05. In addition, VEGF gene expression was significantly higher in all phases of CML: 0.245 in blast crisis, 0.320 in the active phase, and 0.330 in chronic phase patients than it was in healthy subjects (0.145. In conclusion, CML in blast crisis had increased levels of CECs and VEGF gene expression, which may serve as markers of disease progression and may become targets for the management of CML.

Double-stranded RNA promotes CTL-independent tumor cytolysis mediated by CD11b+Ly6G+ intratumor myeloid cells through the TICAM-1 signaling pathway

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Shime, Hiroaki; Matsumoto, Misako; Seya, Tsukasa

2017-01-01

PolyI:C, a synthetic double-stranded RNA analog, acts as an immune-enhancing adjuvant that regresses tumors in cytotoxic T lymphocyte (CTL)-dependent and CTL-independent manner, the latter of which remains largely unknown. Tumors contain CD11b+Ly6G+ cells, known as granulocytic myeloid-derived suppressor cells (G-MDSCs) or tumor-associated neutrophils (TANs) that play a critical role in tumor progression and development. Here, we demonstrate that CD11b+Ly6G+ cells respond to polyI:C and exhibit tumoricidal activity in an EL4 tumor implant model. PolyI:C-induced inhibition of tumor growth was attributed to caspase-8/3 cascade activation in tumor cells that occurred independently of CD8α+/CD103+ dendritic cells (DCs) and CTLs. CD11b+Ly6G+ cells was essential for the antitumor effect because depletion of CD11b+Ly6G+ cells totally abrogated tumor regression and caspase activation after polyI:C treatment. CD11b+Ly6G+ cells that had been activated with polyI:C showed cytotoxicity and inhibited tumor growth through the production of reactive oxygen species (ROS)/reactive nitrogen species (RNS). These responses were abolished in either Toll/interleukin-1 receptor domain-containing adaptor molecule-1 (TICAM-1)−/− or interferon (IFN)-αβ receptor 1 (IFNAR1)−/− mice. Thus, our results suggest that polyI:C activates the TLR3/TICAM-1 and IFNAR signaling pathways in CD11b+Ly6G+ cells in tumors, thereby eliciting their antitumor activity, independent of those in CD8α+/CD103+ DCs that prime CTLs. PMID:27834952

Murine Th9 cells promote the survival of myeloid dendritic cells in cancer immunotherapy.

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Park, Jungsun; Li, Haiyan; Zhang, Mingjun; Lu, Yong; Hong, Bangxing; Zheng, Yuhuan; He, Jin; Yang, Jing; Qian, Jianfei; Yi, Qing

2014-08-01

Dendritic cells (DCs) are professional antigen-presenting cells to initiate immune responses, and DC survival time is important for affecting the strength of T-cell responses. Interleukin (IL)-9-producing T-helper (Th)-9 cells play an important role in anti-tumor immunity. However, it is unclear how Th9 cells communicate with DCs. In this study, we investigated whether murine Th9 cells affected the survival of myeloid DCs. DCs derived from bone marrow of C57BL/6 mice were cocultured with Th9 cells from OT-II mice using transwell, and the survival of DCs was examined. DCs cocultured with Th9 cells had longer survival and fewer apoptotic cells than DCs cultured alone in vitro. In melanoma B16-OVA tumor-bearing mice, DCs conditioned by Th9 cells lived longer and induced stronger anti-tumor response than control DCs did in vivo. Mechanistic studies revealed that IL-3 but not IL-9 secreted by Th9 cells was responsible for the prolonged survival of DCs. IL-3 upregulated the expression of anti-apoptotic protein Bcl-xL and activated p38, ERK and STAT5 signaling pathways in DCs. Taken together, our data provide the first evidence that Th9 cells can promote the survival of DCs through IL-3, and will be helpful for designing Th9 cell immunotherapy and more effective DC vaccine for human cancers.

Targeting myeloid-derived suppressor cells augments antitumor activity against lung cancer

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Srivastava MK

2012-10-01

Full Text Available Minu K Srivastava,1,2 Li Zhu,1,2 Marni Harris-White,2 Min Huang,1–3 Maie St John,1,3 Jay M Lee,1,3 Ravi Salgia,4 Robert B Cameron,1,3,5 Robert Strieter,6 Steven Dubinett,1–3 Sherven Sharma1–31Department of Medicine, UCLA Lung Cancer Research Program, David Geffen School of Medicine at UCLA, Los Angeles, CA, 2Molecular Gene Medicine Laboratory, Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, 3Jonsson Comprehensive Cancer Center, David Geffen School of Medicine at UCLA, Los Angeles, CA, 4Department of Medicine, University of Chicago, Chicago, IL, 5Department of Surgery, Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, CA, 6Department of Medicine, University of Virginia, Charlottesville, VA, USAAbstract: Lung cancer evades host immune surveillance by dysregulating inflammation. Tumors and their surrounding stromata produce growth factors, cytokines, and chemokines that recruit, expand, and/or activate myeloid-derived suppressor cells (MDSCs. MDSCs regulate immune responses and are frequently found in malignancy. In this review the authors discuss tumor-MDSC interactions that suppress host antitumor activities and the authors' recent findings regarding MDSC depletion that led to improved therapeutic vaccination responses against lung cancer. Despite the identification of a repertoire of tumor antigens, hurdles persist for immune-based anticancer therapies. It is likely that combined therapies that address the multiple immune deficits in cancer patients will be required for effective therapy. MDSCs play a major role in the suppression of T-cell activation and they sustain tumor growth, proliferation, and metastases. Regulation of MDSC recruitment, differentiation or expansion, and inhibition of the MDSC suppressive function with pharmacologic agents will be useful in the control of cancer growth and progression. Pharmacologic agents that regulate MDSCs may be more effective when combined with