Novel therapeutic strategies to target leukemic cells that hijack compartmentalized continuous hematopoietic stem cell niches.

Science.gov (United States)

Hira, Vashendriya V V; Van Noorden, Cornelis J F; Carraway, Hetty E; Maciejewski, Jaroslaw P; Molenaar, Remco J

2017-08-01

Acute myeloid leukemia and acute lymphoblastic leukemia cells hijack hematopoietic stem cell (HSC) niches in the bone marrow and become leukemic stem cells (LSCs) at the expense of normal HSCs. LSCs are quiescent and resistant to chemotherapy and can cause relapse of the disease. HSCs in niches are needed to generate blood cell precursors that are committed to unilineage differentiation and eventually production of mature blood cells, including red blood cells, megakaryocytes, myeloid cells and lymphocytes. Thus far, three types of HSC niches are recognized: endosteal, reticular and perivascular niches. However, we argue here that there is only one type of HSC niche, which consists of a periarteriolar compartment and a perisinusoidal compartment. In the periarteriolar compartment, hypoxia and low levels of reactive oxygen species preserve the HSC pool. In the perisinusoidal compartment, hypoxia in combination with higher levels of reactive oxygen species enables proliferation of progenitor cells and their mobilization into the circulation. Because HSC niches offer protection to LSCs against chemotherapy, we review novel therapeutic strategies to inhibit homing of LSCs in niches for the prevention of dedifferentiation of leukemic cells into LSCs and to stimulate migration of leukemic cells out of niches. These strategies enhance differentiation and proliferation and thus sensitize leukemic cells to chemotherapy. Finally, we list clinical trials of therapies that tackle LSCs in HSC niches to circumvent their protection against chemotherapy. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

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.

Fundamental studies of leukemic cell labeling with /sup 111/In-oxine and their applications to cell kinetics in patients with acute leukemia

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Takagi, Yuhkoh; Matsuda, Shin; Uchida, Tatsumi; Kariyone, Shigeo [Fukushima Medical Coll. (Japan)

1984-04-01

Fundamental studies of leukemic cell labeling with /sup 111/In-oxine and their applications to leukemic cell kinetics in five patients with acute myeloblastic leukemia (AML) were examined. Labeling efficiency of leukemic cells was 80.3 +- 3.6% for more than 1 x 10/sup 8/ cells at room temperature for 20 minutes of incubation followed by two times washes. Cell viability determined by means of trypanblue exclusion test was 95.3 +- 2.6%. In vitro elution rate of /sup 111/In from the labeled cells during 12 hours was 10.0 +- 1.2%. The disappearance curves of labeled leukemic cells in AMLs followed a single exponential fashion, and the half time of disappearance (T 1/2) ranged from 9.6 to 31.8 hours. Total blood leukemic cell pool (TBLCP) calculated with the dilution principles of radioisotopes correlated significantly with the leukemic cell counts (LC) in the peripheral blood (Y = 0.32 + 1.94X, r = 0.99). In the studies of organ distribution which were observed and analyzed with gamma camera and computer, labeled leukemic cells passed through lungs within 15 minutes. Radioactivity in the spleen increased rapidly for 30 - 60 minutes, then reached a plateau. Hepatic radioactivity showed a temporary decrease during 10 - 60 minutes following the moderate accumulation in initial 10 minutes. In two cases, bone marrow was visualized 24 hours after the injection. Radioactivity of the leukemic cells isolated from the bone marrow at 22 hours after the injection in one case was one third of the radioactivity in leukemic cells obtained from the peripheral blood at the same time.

Molecular dynamics study of lipid bilayers modeling the plasma membranes of normal murine thymocytes and leukemic GRSL cells.

Science.gov (United States)

Andoh, Yoshimichi; Okazaki, Susumu; Ueoka, Ryuichi

2013-04-01

Molecular dynamics (MD) calculations for the plasma membranes of normal murine thymocytes and thymus-derived leukemic GRSL cells in water have been performed under physiological isothermal-isobaric conditions (310.15K and 1 atm) to investigate changes in membrane properties induced by canceration. The model membranes used in our calculations for normal and leukemic thymocytes comprised 23 and 25 kinds of lipids, respectively, including phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidylinositol, sphingomyelin, lysophospholipids, and cholesterol. The mole fractions of the lipids adopted here were based on previously published experimental values. Our calculations clearly showed that the membrane area was increased in leukemic cells, and that the isothermal area compressibility of the leukemic plasma membranes was double that of normal cells. The calculated membranes of leukemic cells were thus considerably bulkier and softer in the lateral direction compared with those of normal cells. The tilt angle of the cholesterol and the conformation of the phospholipid fatty acid tails both showed a lower level of order in leukemic cell membranes compared with normal cell membranes. The lateral radial distribution function of the lipids also showed a more disordered structure in leukemic cell membranes than in normal cell membranes. These observations all show that, for the present thymocytes, the lateral structure of the membrane is considerably disordered by canceration. Furthermore, the calculated lateral self-diffusion coefficient of the lipid molecules in leukemic cell membranes was almost double that in normal cell membranes. The calculated rotational and wobbling autocorrelation functions also indicated that the molecular motion of the lipids was enhanced in leukemic cell membranes. Thus, here we have demonstrated that the membranes of thymocyte leukemic cells are more disordered and more fluid than normal cell membranes. Copyright © 2013

The in-vitro study of human blood leukemic cells by pulsed NMR

International Nuclear Information System (INIS)

Zulkarnaen, M.; Munawir; Wibowo, Tono; Suyitno, Gogot

1983-01-01

The diagram of leukemic cells in human blood has been studied by using the NMR longitudinal relaxation technique. The observation was treated in whole blood, serum and blood cell. Every result was compared with previous observation and show that the values of the proton longitudinal relaxation in the leukemic whole blood almost twice or more that of normal blood, while in the serum and the blood cell, the values are nearly the same. (author)

Resistance of some leukemic blasts to lysis by lymphokine activated killer (LAK) cells

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Panayotides, P; Sjoegren, A -M; Reizenstein, P; Porwit, A. Immunopathology Lab., Dept. of Pathology, Karolinska Hospital, Stockholm; Wasserman, J

1988-01-01

Peripheral blood mononuclear cells (PBMC) from healthy donors and AML patients in remission were stimulated with phytohemagglutinin (PHA) and recombinant interleukin-2 (IL-2). These stimulated cells (lymphokine activated killer (LAK) cells) showed increased DNA synthesis as measured by /sup 3/H-Thymidine uptake. A synergistic effect of PHA and IL-2 was found. LAK cells' ability to kill acute myeloid leukemia (AML) blasts was investigated by the /sup 51/Cr release assay. LAK cells showed a cytotoxicity (over 10% specific /sup 51/Cr release) against 9/12 leukemic blasts, even at effector/target (E/T) ratios as low as 5:1. However, on average only 22.2% (SD 11.8) and 36.5% (SD 12.5) /sup 51/Cr release were obtained in 4- and 18-hour cytotoxicity assays, respectively, at an E/T ratio of 20:1. Leukemic blasts in 3/12 AML cases and normal PBMC were entirely resistant to lysis, even at an E/T ratio of 80:1. Susceptibility to lysis was not correlated to peanut-agglutinin receptor expression. LAK cells were more cytotoxic towards the K-562 cell line (natural killer activity) than unstimulated PBMC.

Differential Activity of Voltage- and Ca2+-Dependent Potassium Channels in Leukemic T Cell Lines: Jurkat Cells Represent an Exceptional Case

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Salvador Valle-Reyes

2018-05-01

Full Text Available Activation of resting T cells relies on sustained Ca2+ influx across the plasma membrane, which in turn depends on the functional expression of potassium channels, whose activity repolarizes the membrane potential. Depending on the T-cells subset, upon activation the expression of Ca2+- or voltage-activated K+ channels, KCa or Kv, is up-regulated. In this study, by means of patch-clamp technique in the whole cell mode, we have studied in detail the characteristics of Kv and KCa currents in resting and activated human T cells, the only well explored human T-leukemic cell line Jurkat, and two additional human leukemic T cell lines, CEM and MOLT-3. Voltage dependence of activation and inactivation of Kv1.3 current were shifted up to by 15 mV to more negative potentials upon a prolonged incubation in the whole cell mode and displayed little difference at a stable state in all cell lines but CEM, where the activation curve was biphasic, with a high and low potential components. In Jurkat, KCa currents were dominated by apamine-sensitive KCa2.2 channels, whereas only KCa3.1 current was detected in healthy T and leukemic CEM and MOLT-3 cells. Despite a high proliferation potential of Jurkat cells, Kv and KCa currents were unexpectedly small, more than 10-fold lesser as compared to activated healthy human T cells, CEM and MOLT-3, which displayed characteristic Kv1.3high:KCa3.1high phenotype. Our results suggest that Jurkat cells represent perhaps a singular case and call for more extensive studies on primary leukemic T cell lines as well as a verification of the therapeutic potential of specific KCa3.1 blockers to combat acute lymphoblastic T leukemias.

Anti-leukemic therapies induce cytogenetic changes of human bone marrow-derived mesenchymal stem cells.

Science.gov (United States)

Yeh, Su-Peng; Lo, Wen-Jyi; Lin, Chiao-Lin; Liao, Yu-Min; Lin, Chen-Yuan; Bai, Li-Yuan; Liang, Ji-An; Chiu, Chang-Fang

2012-02-01

Both bone marrow hematopoietic cells (BM-HCs) and mesenchymal stem cells (BM-MSCs) may have cytogenetic aberrations in leukemic patients, and anti-leukemic therapy may induce cytogenetic remission of BM-HCs. The impact of anti-leukemic therapy on BM-MSCs remains unknown. Cytogenetic studies of BM-MSCs from 15 leukemic patients with documented cytogenetic abnormalities of BM-HCs were investigated. To see the influence of anti-leukemic therapy on BM-MSCs, cytogenetic studies were carried out in seven of them after the completion of anti-leukemic therapy, including anthracycline/Ara-C-based chemotherapy in two patients, high-dose busulfan/cyclophosphamide-based allogeneic transplantation in two patients, and total body irradiation (TBI)-based allogeneic transplantation in three patients. To simulate the effect of TBI in vitro, three BM-MSCs from one leukemic patient and two normal adults were irradiated using the same dosage and dosing schedule of TBI and cytogenetics were re-examined after irradiation. At the diagnosis of leukemia, two BM-MSCs had cytogenetic aberration, which were completely different to their BM-HCs counterpart. After the completion of anti-leukemic therapy, cytogenetic aberration was no longer detectable in one patient. Unexpectedly, BM-MSCs from three patients receiving TBI-based allogeneic transplantation acquired new, clonal cytogenetic abnormalities after transplantation. Similarly, complex cytogenetic abnormalities were found in all the three BM-MSCs exposed to in vitro irradiation. In conclusion, anti-leukemic treatments induce not only "cytogenetic remission" but also new cytogenetic abnormalities of BM-MSCs. TBI especially exerts detrimental effect on the chromosomal integrity of BM-MSCs and highlights the equal importance of investigating long-term adverse effect of anti-leukemic therapy on BM-MSCs as opposed to beneficial effect on BM-HCs.

Interaction between the immune system and acute myeloid leukemia: A model incorporating promotion of regulatory T cell expansion by leukemic cells.

Science.gov (United States)

Nishiyama, Yoshiaki; Saikawa, Yutaka; Nishiyama, Nobuaki

2018-03-01

Population dynamics of regulatory T cells (Treg) are crucial for the underlying interplay between leukemic and immune cells in progression of acute myeloid leukemia (AML). The goal of this work is to elucidate the dynamics of a model that includes Treg, which can be qualitatively assessed by accumulating clinical findings on the impact of activated immune cell infusion after selective Treg depletion. We constructed an ordinary differential equation model to describe the dynamics of three components in AML: leukemic blast cells, mature regulatory T cells (Treg), and mature effective T cells (Teff), including cytotoxic T lymphocytes. The model includes promotion of Treg expansion by leukemic blast cells, leukemic stem cell and progenitor cell targeting by Teff, and Treg-mediated Teff suppression, and exhibits two coexisting, stable steady states, corresponding to high leukemic cell load at diagnosis or relapse, and to long-term complete remission. Our model is capable of explaining the clinical findings that the survival of patients with AML after allogeneic stem cell transplantation is influenced by the duration of complete remission, and that cut-off minimal residual disease thresholds associated with a 100% relapse rate are identified in AML. Copyright © 2018 Elsevier B.V. All rights reserved.

Demonstration of interleukin-1 beta transcripts in acute myeloblastic leukemic cells by in situ hybridization.

Science.gov (United States)

Nakamura, M; Kanakura, Y; Furukawa, Y; Ernst, T J; Griffin, J D

1990-07-01

The cells from some patients with acute myeloblastic leukemia will secrete autostimulatory cytokines in tissue culture without the addition of stimulators such as phorbol 12-myristate 13-acetate. Production of interleukin-1 beta (IL-1 beta), for example, has been observed in up to 50% of cases. In order to investigate the nature of the cell secreting IL-1 beta in AML, we used an antisense RNA probe to detect specific IL-1 beta transcripts in individual leukemic cells by in situ hybridization. In fresh, uncultured cells, IL-1 beta transcripts were observed in 1-40% of undifferentiated leukemic blast cells in 17 of 19 cases. In situ hybridization was at least as sensitive as Northern blot analysis in detecting IL-1 beta transcripts. No correlation of IL-1 beta transcript expression with FAB classification was observed. Normal blood and bone marrow mononuclear cells did not contain cells expressing IL-1 beta transcripts. These results support the concept that the regulation of cytokine genes in AML cells is aberrant.

Clonal evolution of pre-leukemic hematopoietic stem cells precedes human acute myeloid leukemia.

Science.gov (United States)

Majeti, Ravindra

2014-01-01

Massively parallel DNA sequencing has uncovered recurrent mutations in many human cancers. In acute myeloid leukemia (AML), cancer genome/exome resequencing has identified numerous recurrently mutated genes with an average of 5 mutations in each case of de novo AML. In order for these multiple mutations to accumulate in a single lineage of cells, they are serially acquired in clones of self-renewing hematopoietic stem cells (HSC), termed pre-leukemic HSC. Isolation and characterization of pre-leukemic HSC have shown that their mutations are enriched in genes involved in regulating DNA methylation, chromatin modifications, and the cohesin complex. On the other hand, genes involved in regulating activated signaling are generally absent. Pre-leukemic HSC have been found to persist in clinical remission and may ultimately give rise to relapsed disease through the acquisition of novel mutations. Thus, pre-leukemic HSC may constitute a key cellular reservoir that must be eradicated for long-term cures. Copyright © 2014 Elsevier Ltd. All rights reserved.

Analysis of the surface membrane of iodinated leukemic cells by SDS-polyacrylamide gel electrophoresis

International Nuclear Information System (INIS)

Ishitani, Kunihiko; Ikeda, Akira; Tamura, Minoru; Takeuchi, Hidekazu; Ihara, Koji

1980-01-01

Surface proteins of human leukemic cells were labeled selectively by lactoperoxydase catalysed-iodination and examined by SDS-polyacrylamide gel electrophoresis. The electrophoretic pattern of the surface membranes of cells from a patients with chronic mylogeneous leukemia in blast crisis was of B cell type and showed Ia like antigen. Leukemic cells from a patient with hairly cell leukemia also expressed the pattern of B cell type when tested by this method the technique of iodinating cell surface with lactoperoxidase is useful in characterization of leukemia cells for diagnosis and monitoring of clinical course. (author)

In vitro gamma irradiation Medical Center of leukemic cells in mice, rats, and guinea pigs

International Nuclear Information System (INIS)

Gross, L.; Dreyfuss, Y.; Ehrenreich, T.; Feldman, D.; Limbert, L.M.

1980-01-01

In vitro gamma irradiation of virus-induced (Gross) mouse leukemia cells at doses of 350 to 1600 rads (1 rad = 0.01 gray) had no effect on their ability to induce leukemia, usually within 2 weeks, after transplantation into syngeneic mice. However, when cells irradiated at doses of 2000-20,000 rads were transplanted, they induced leukemia after a latency period exceeding 2.5 months, similar to the results observed in mice inoculated with filtered mouse leukemia extracts. Similar results were also obtained after irradiation of leukemic cells derived from rats in which leukemia had been induced by rat-adapted mouse leukemia virus. Apparently, gamma irradiation at a dose of, or exceeding, 2000 rads, inhibits the ability of mouse and rat leukemic cells to induce leukemia after transplantation into syngeneic hosts; however, it does not inactivate the virus carried by such cells nor prevent it from inducing leukemia. [In previous experiments, doses of more than 4,500,000 rads were needed to inactivate the passage A (Gross) leukemia virus carried in either mouse or rat leukemic cells.] In vitro gamma irradiation of L2C guinea pig leukemic cells at doses of 750 to 2500 rads had no apparent effect on their ability to induce leukemia after transplantation into strain 2 guinea pigs. However, irradiation at doses of 3250 to 20,000 rads inactivated their ability to do so. The morphology of mouse, rat, and guinea pig leukemic cells and the virus particles present in such cells was not affected by irradiation at doses of 20,000 rads

Noninvasive identification of subcellular organization and nuclear morphology features associated with leukemic cells using light-scattering spectroscopy

Science.gov (United States)

Hsiao, Austin; Hunter, Martin; Greiner, Cherry; Gupta, Sharad; Georgakoudi, Irene

2011-03-01

Leukemia is the most common and deadly cancer among children and one of the most prevalent cancers among adults. Improvements in its diagnosis and monitoring of leukemic patients could have a significant impact in their long-term treatment. We demonstrate that light-scattering spectroscopy (LSS)-based approaches could serve as a tool to achieve this goal. Specifically, we characterize the light scattering properties of leukemic (NALM-6) cells and compare them to those of normal lymphocytes and granulocytes in the 440-710 nm range, over +/-4 deg about the exact backscattering direction. We find that the LSS spectra are well described by an inverse power-law wavelength dependence, with a power exponent insensitive to the scattering angle but significantly higher for leukemic cells than for normal leukocytes. This is consistent with differences in the subcellular morphology of these cells, detected in differential interference contrast images. Furthermore, the residual light-scattering signal, extracted after subtracting the inverse power-law fit from the data, can be analyzed assuming a Gaussian distribution of spherical scatterers using Mie theory. This analysis yields scatterer sizes that are consistent with the diameters of cell nuclei and allows the detection of the larger nuclei of NALM-6 cells compared to those of lymphocytes and granulocytes.

Leukemic optic neuropathy.

Science.gov (United States)

Brown, G C; Shields, J A; Augsburger, J J; Serota, F T; Koch, P

1981-03-01

The clinical course and ophthalmic manifestations of an eight year old child with acute undifferentiated leukemia and unilateral blindness secondary to leukemic optic nerve head infiltration are described. At autopsy the involved nerve head and peripapillary retina demonstrated massive leukemic cell infiltration and hemorrhagic necrosis. This manifestation of leukemia is quite uncommon and prognosis for life in such cases is poor with existing methods of therapy.

Studies by radioiodination of normal adult, fetal and leukemic cell membranes

Energy Technology Data Exchange (ETDEWEB)

Kannourakis, G; Cauchi, M N [Department of Pathology and Immunology, Monash Medical School, Melbourne, Australia

1978-01-01

A comparison was made between cord blood lymphocytes, normal adult lymphocytes and leukemic cells after membrane iodination with lactoperoxidase. A double-labeling technique using lactoperoxidase iodination with /sup 125/I and /sup 131/I followed by analysis on polyacrylamide gel electrophoresis revealed a number of membrane differences between leukemic, normal and fetal cells. There was a reduction in the 70,000 molecular weight component in cord blood cells compared to adult lymphocytes, and an increase in membrane peptides with molecular weights of 35,000, 20,000, 9,000 and 4,000. Although smaller molecular weight peptides were also present in chronic lymphatic leukemia as well as acute myeloid leukemia, these were shown to be distinct from fetal type membrane components.

Leukemic Cells "Gas Up" Leaky Bone Marrow Blood Vessels.

Science.gov (United States)

Itkin, Tomer; Rafii, Shahin

2017-09-11

In this issue of Cancer Cell, Passaro et al. demonstrate how leukemia through aberrant induction of reactive oxygen species and nitric oxide production trigger marrow vessel leakiness, instigating pro-leukemic function. Disrupted tumor blood vessels promote exhaustion of non-malignant stem and progenitor cells and may facilitate leukemia relapse following chemotherapeutic treatment. Copyright © 2017. Published by Elsevier Inc.

Profound radiosensitivity in leukemic T-cell lines and T-cell-type acute lymphoblastic leukemia demonstrated by sodium [51Cr]chromate labeling

International Nuclear Information System (INIS)

Nakazawa, S.; Minowada, J.; Tsubota, T.; Sinks, L.F.

1978-01-01

Radiation sensitivity was determined by measuring spontaneous release from 51 Cr-labeled cells in various lymphoid cell populations. Among six leukemia T-cell lines originating from acute lymphoblastic leukemia, four such lines were found to be highly radiosensitive. In contrast, two of the leukemic T-cell lines and four normal control B-cell lines were not radiosensitive. Thymocytes from six patients and leukemia T-cell blasts from three patients with T-cell leukemia were likewise found to be highly radiosensitive, whereas leukemic blasts from six patients with null-cell (non-T, non-B-cell) acute lymphoblastic leukemia were not radiosensitive. Normal peripheral blood lymphocytes and mitogen-induced normal lymphoblasts were found not to be radiosensitive. The results indicate that measurement of the radiation sensitivity of acute leukemic blasts may have a therapeutic significance in coping with the heterogeneous nature of individual leukemia cases

Generation of TCR-Expressing Innate Lymphoid-like Helper Cells that Induce Cytotoxic T Cell-Mediated Anti-leukemic Cell Response.

Science.gov (United States)

Ueda, Norihiro; Uemura, Yasushi; Zhang, Rong; Kitayama, Shuichi; Iriguchi, Shoichi; Kawai, Yohei; Yasui, Yutaka; Tatsumi, Minako; Ueda, Tatsuki; Liu, Tian-Yi; Mizoro, Yasutaka; Okada, Chihiro; Watanabe, Akira; Nakanishi, Mahito; Senju, Satoru; Nishimura, Yasuharu; Kuzushima, Kiyotaka; Kiyoi, Hitoshi; Naoe, Tomoki; Kaneko, Shin

2018-06-05

CD4 + T helper (Th) cell activation is essential for inducing cytotoxic T lymphocyte (CTL) responses against malignancy. We reprogrammed a Th clone specific for chronic myelogenous leukemia (CML)-derived b3a2 peptide to pluripotency and re-differentiated the cells into original TCR-expressing T-lineage cells (iPS-T cells) with gene expression patterns resembling those of group 1 innate lymphoid cells. CD4 gene transduction into iPS-T cells enhanced b3a2 peptide-specific responses via b3a2 peptide-specific TCR. iPS-T cells upregulated CD40 ligand (CD40L) expression in response to interleukin-2 and interleukin-15. In the presence of Wilms tumor 1 (WT1) peptide, antigen-specific dendritic cells (DCs) conditioned by CD4-modified CD40L high iPS-T cells stimulated WT1-specific CTL priming, which eliminated WT1 peptide-expressing CML cells in vitro and in vivo. Thus, CD4 modification of CD40L high iPS-T cells generates innate lymphoid helper-like cells inducing bcr-abl-specific TCR signaling that mediates effectiveanti-leukemic CTL responses via DC maturation, showing potential for adjuvant immunotherapy against leukemia. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Novel therapeutic strategies to target leukemic cells that hijack compartmentalized continuous hematopoietic stem cell niches

NARCIS (Netherlands)

Hira, Vashendriya V. V.; van Noorden, Cornelis J. F.; Carraway, Hetty E.; Maciejewski, Jaroslaw P.; Molenaar, Remco J.

2017-01-01

Acute myeloid leukemia and acute lymphoblastic leukemia cells hijack hematopoietic stem cell (HSC) niches in the bone marrow and become leukemic stem cells (LSCs) at the expense of normal HSCs. LSCs are quiescent and resistant to chemotherapy and can cause relapse of the disease. HSCs in niches are

Human TM9SF4 Is a New Gene Down-Regulated by Hypoxia and Involved in Cell Adhesion of Leukemic Cells.

Directory of Open Access Journals (Sweden)

Rosa Paolillo

Full Text Available The transmembrane 9 superfamily protein member 4, TM9SF4, belongs to the TM9SF family of proteins highly conserved through evolution. TM9SF4 homologs, previously identified in many different species, were mainly involved in cellular adhesion, innate immunity and phagocytosis. In human, the function and biological significance of TM9SF4 are currently under investigation. However, TM9SF4 was found overexpressed in human metastatic melanoma and in a small subset of acute myeloid leukemia (AMLs and myelodysplastic syndromes, consistent with an oncogenic function of this gene.In this study, we first analyzed the expression and regulation of TM9SF4 in normal and leukemic cells and identified TM9SF4 as a gene highly expressed in human quiescent CD34+ hematopoietic progenitor cells (HPCs, regulated during monocytic and granulocytic differentiation of HPCs, both lineages giving rise to mature myeloid cells involved in adhesion, phagocytosis and immunity. Then, we found that TM9SF4 is markedly overexpressed in leukemic cells and in AMLs, particularly in M2, M3 and M4 AMLs (i.e., in AMLs characterized by the presence of a more or less differentiated granulocytic progeny, as compared to normal CD34+ HPCs. Proliferation and differentiation of HPCs occurs in hypoxia, a physiological condition in bone marrow, but also a crucial component of cancer microenvironment. Here, we investigated the impact of hypoxia on TM9SF4 expression in leukemic cells and identified TM9SF4 as a direct target of HIF-1α, downregulated in these cells by hypoxia. Then, we found that the hypoxia-mediated downregulation of TM9SF4 expression is associated with a decrease of cell adhesion of leukemic cells to fibronectin, thus demonstrating that human TM9SF4 is a new molecule involved in leukemic cell adhesion.Altogether, our study reports for the first time the expression of TM9SF4 at the level of normal and leukemic hematopoietic cells and its marked expression at the level of AMLs

Anti-leukemic activity of bortezomib and carfilzomib on B-cell precursor ALL cell lines.

Directory of Open Access Journals (Sweden)

Kazuya Takahashi

Full Text Available Prognosis of childhood acute lymphoblastic leukemia (ALL has been dramatically improved. However, prognosis of the cases refractory to primary therapy is still poor. Recent phase 2 study on the efficacy of combination chemotherapy with bortezomib (BTZ, a proteasome inhibitor, for refractory childhood ALL demonstrated favorable clinical outcomes. However, septic death was observed in over 10% of patients, indicating the necessity of biomarkers that could predict BTZ sensitivity. We investigated in vitro BTZ sensitivity in a large panel of ALL cell lines that acted as a model system for refractory ALL, and found that Philadelphia chromosome-positive (Ph+ ALL, IKZF1 deletion, and biallelic loss of CDKN2A were associated with favorable response. Even in Ph-negative ALL cell lines, IKZF1 deletion and bilallelic loss of CDKN2A were independently associated with higher BTZ sensitivity. BTZ showed only marginal cross-resistance to four representative chemotherapeutic agents (vincristine, dexamethasone, l-asparaginase, and daunorubicin in B-cell precursor-ALL cell lines. To improve the efficacy and safety of proteasome inhibitor combination chemotherapy, we also analyzed the anti-leukemic activity of carfilzomib (CFZ, a second-generation proteasome inhibitor, as a substitute for BTZ. CFZ showed significantly higher activity than BTZ in the majority of ALL cell lines except for the P-glycoprotein-positive t(17;19 ALL cell lines, and IKZF1 deletion was also associated with a favorable response to CFZ treatment. P-glycoprotein inhibitors effectively restored the sensitivity to CFZ, but not BTZ, in P-glycoprotein-positive t(17;19 ALL cell lines. P-glycoprotein overexpressing ALL cell line showed a CFZ-specific resistance, while knockout of P-glycoprotein by genome editing with a CRISPR/Cas9 system sensitized P-glycoprotein-positive t(17;19 ALL cell line to CFZ. These observations suggested that IKZF1 deletion could be a useful biomarker to predict good

Towards The Generation of Functionalized Magnetic Nanowires to Target Leukemic Cells

KAUST Repository

Alsharif, Nouf

2016-04-01

In recent years, magnetic nanowires (NWs) have been widely used for their therapeutic potential in biomedical applications. The use of iron (Fe) NWs combines two important properties, biocompatibility and remote manipulation by magnetic fields. In addition the NWs can be coated and functionalized to target cells of interest and, upon exposure to an alternating magnetic field, have been shown to induce cell death on several types of adherent cells, including several cancer cell types. For suspension cells, however, using these NWs has been much less effective primarily due to the free-floating nature of the cells minimizing the interaction between them and the NWs. Leukemic cells express higher levels of the cell surface marker CD44 (Braumüller, Gansauge, Ramadani, & Gansauge, 2000), compared to normal blood cells. The goal of this study was to functionalize Fe NWs with a specific monoclonal antibody towards CD44 in order to target leukemic cells (HL-60 cells). This approach is expected to increase the probability of a specific binding to occur between HL-60 cells and Fe NWs. Fe NWs were fabricated with an average diameter of 30-40 nm and a length around 3-4 μm. Then, they were coated with both 3-Aminopropyl-triethoxysilane and bovine serum albumin (BSA) in order to conjugate them with an anti-CD44 antibody (i.e. anti-CD44-iron NWs). The antibody interacts with the amine group in the BSA via the 1-Ethyl-3-3-dimethylaminopropyl-carbodiimide and N-Hydroxysuccinimide coupling. The NWs functionalization was confirmed using a number of approaches including: infrared spectroscopy, Nanodrop to measure the concentration of CD44 antibody, as well as fluorescent-labeled secondary antibody staining to detect the primary CD44 antibody. To confirm that the anti-CD44-iron NWs and bare Fe NWs, in the absence of a magnetic field, were not toxic to HL-60 cells, cytotoxicity assays using XTT (2,3-Bis-2-Methoxy-4-Nitro-5-Sulfophenyl-2H-Tetrazolium-5-Carboxanilide) were performed and

Chemotherapy impedes in vitro microcirculation and promotes migration of leukemic cells with impact on metastasis

International Nuclear Information System (INIS)

Prathivadhi-Bhayankaram, Sruti V.; Ning, Jianhao; Mimlitz, Michael; Taylor, Carolyn; Gross, Erin; Nichols, Michael; Guck, Jochen; Ekpenyong, Andrew E.

2016-01-01

Although most cancer drugs target the proliferation of cancer cells, it is metastasis, the complex process by which cancer cells spread from the primary tumor to other tissues and organs of the body where they form new tumors, that leads to over 90% of all cancer deaths. Thus, there is an urgent need for anti-metastasis therapy. Surprisingly, emerging evidence suggests that certain anti-cancer drugs such as paclitaxel and doxorubicin can actually promote metastasis, but the mechanism(s) behind their pro-metastatic effects are still unclear. Here, we use a microfluidic microcirculation mimetic (MMM) platform which mimics the capillary constrictions of the pulmonary and peripheral microcirculation, to determine if in-vivo-like mechanical stimuli can evoke different responses from cells subjected to various cancer drugs. In particular, we show that leukemic cancer cells treated with doxorubicin and daunorubicin, commonly used anti-cancer drugs, have over 100% longer transit times through the device, compared to untreated leukemic cells. Such delays in the microcirculation are known to promote extravasation of cells, a key step in the metastatic cascade. Furthermore, we report a significant (p < 0.01) increase in the chemotactic migration of the doxorubicin treated leukemic cells. Both enhanced retention in the microcirculation and enhanced migration following chemotherapy, are pro-metastatic effects which can serve as new targets for anti-metastatic drugs. - Highlights: • Doxorubicin enhances migration of leukemic cancer cells before cell death. • Doxorubicin and Daunorubicin stiffen and delay cells in mimicked microcirculation. • Some cancer drugs cause changes in cell mechanics that lead to pro-metastatic effects. • Cell mechanics becomes a new target for anti-metastatic drugs.

Altered expression of asparagine synthetase mRNA in human leukemic and carcinoma cell lines

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Goodwin, L.O.; Guzowski, D.E.; Millan, C.A. [North Shore Univ. Hospital/Cornell Univ. Medical College, Manhasset, NY (United States)] [and others

1994-09-01

Asparagine synthetase (AS) is the enzyme responsible for the ATP-dependant conversion of aspartic acid to asparagine. The AS gene is expressed constitutively in most mammalian cells, including cells of the lymphoid lineage, as a 2 kb mRNA. In some leukemic phenotypes, AS expression is abrogated, resulting in no detectable enzyme activity. These cells are rendered sensitive to killing by L-asparaginase, which destroys extracellular asparagine. Prolonged treatment of leukemic cells with this agent can lead to resistance and the reappearance of AS activity, suggesting derepression of the AS gene, which has been shown to be regulated by intracellular levels of asparagine. Modulation of AS expression by asparagine employs cis and trans-acting elements involved in transcriptional and translational regulation. We have cloned and sequenced the human AS gene and surrounding sequence elements as well as the full-length cDNA. Using probes specific to the third and fourth exons of AS, we have identified an additional higher molecular weight mRNA (2.7 kb) in Northern blots derived from a chronic myelogenous leukemia and a colon carcinoma but not in normal lymphocytic or other human cell lines. We speculate that elements present in the cancer-derived mRNAs may be involved in the derepression of AS activity. This hypothesis is being evaluated by RNase protection assays using RNA isolated from a variety of human cell lines to characterize and elucidate the nature of this additional AS encoded message.

Combined Treatment with Low Concentrations of Decitabine and SAHA Causes Cell Death in Leukemic Cell Lines but Not in Normal Peripheral Blood Lymphocytes

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Barbora Brodská

2013-01-01

Full Text Available Epigenetic therapy reverting aberrant acetylation or methylation offers the possibility to target preferentially tumor cells and to preserve normal cells. Combination epigenetic therapy may further improve the effect of individual drugs. We investigated combined action of demethylating agent decitabine and histone deacetylase inhibitor SAHA (Vorinostat on different leukemic cell lines in comparison with peripheral blood lymphocytes. Large decrease of viability, as well as huge p21WAF1 induction, reactive oxygen species formation, and apoptotic features due to combined decitabine and SAHA action were detected in leukemic cell lines irrespective of their p53 status, while essentially no effect was observed in response to the combined drug action in normal peripheral blood lymphocytes of healthy donors. p53-dependent apoptotic pathway was demonstrated to participate in the wtp53 CML-T1 leukemic cell line response, while significant influence of reactive oxygen species on viability decrease has been detected in p53-null HL-60 cell line.

Normal and Leukemic Hematopoiesis

NARCIS (Netherlands)

Vercauteren, Suzanne Maria

2003-01-01

Acute Myeloid Leukemia (AML) is a clonal myeloproliferative disease characterized by an uncontrolled proliferation and block in differentiation of myeloid committed blood cells in the bone marrow. Despite the lack of mature cells derived from the leukemic clone in the majority of AML patients, AML

Uncontrolled hypertension secondary to leukemic cell infiltration of kidneys in a hemodialysis patient

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Kultigin Turkmen

2010-06-01

Full Text Available Kultigin Turkmen1, Lutfullah Altintepe2, Ibrahim Guney2, Ismet Aydogdu3, Osman Koc4, Mehmet Ali Erkut5, Halil Zeki Tonbul11Department of Nephrology, Meram School of Medicine, Selcuk University, 2Meram Training and Research Hospital, Selcuk University, 3Department of Hematology, Meram School of Medicine, Selcuk University, 4Department of Radiology, Meram School of Medicine, Selcuk University, 5Department of Hematology, Meram Training and Research Hospital, Selcuk UniversityAbstract: Leukemic infiltration of the kidney is usually silent, and the admission of the patients with renal dysfunction or acute kidney injury is uncommon. We present a 34-year old hemodialysis patient with new onset of uncontrolled hypertension, erythropoietin-resistant anemia, thrombocytopenia, and Bell’s palsy. On admission, his blood pressure (BP was 210/110 mmHg and he had petechiae and purpura at upper and lower extremities. Renal ultrasonography (USG showed bilaterally enlarged kidneys without hydronephrosis, unlike his previous USG, which determined bilaterally atrophic kidneys. Acute lymphoblastic leukemia, hypertensive crisis due to bilateral leukemic cell infiltration of kidneys, tumor lysis syndrome, and leukemic involvement of the facial nerve were diagnosed. Despite intense antihypertensive management, his BP was not controlled. After prednisolone, daunorubicine, and vincristine therapy, the size of kidneys diminished and his BP dropped under normal range. In conclusion, pathological findings such as uncontrolled hypertension, flank pain, skin rashes, and abnormal blood count should be considered carefully, even in patients with end-stage renal disease receiving renal replacement therapy.Keywords: leukemic cell infiltration, uncontrolled hypertension, hemodialysis

Transfer RNA species in human lymphocytes stimulated by mitogens and in leukemic cells. [/sup 3/H, /sup 14/C, /sup 32/P tracer techniques

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Griffin, G.D.; Yang, W.K.; Novelli, G.D.

1976-01-01

Transfer ribonucleic acid (tRNA) profiles in human lymphocytes stimulated by various mitogens have been compared with profiles from nonstimulated cells and from leukemic cells using reversed-phase chromatography. Comparisons of (/sup 3/H)- or (/sup 11/C)uridine- or (/sup 32/P)phosphate-labeled tRNAs showed that the greatest changes in tRNA composition upon phytohemagglutinin (PHA) stimulation occurred in the first 8 h after mitogen addition. Stimulation of lymphocytes by pokeweed mitogen, anti-human immunoglobulin, or bacterial lipopolysaccharide resulted in tRNA species which showed distinct differences from each other and also from the tRNAs produced by phytohemagglutinin stimulation. Leukemic lymphocyte tRNAs showed the most extensive differences in profile when compared with chromatograms from non-neoplastic cells stimulated by a variety of mitogens. Specific isoaccepting species of tyrosyl-, aspartyl-, and phenylalanyl-tRNAs were also compared in PHA-stimulated and resting lymphocytes and no differences were found. When these same species were studied in leukemic cells, tyrosyl-tRNA profiles were shifted to elute at a lower salt concentration, while the aspartyl-tRNA profile showed a new peak not present in noncancerous cells.

Leukemic blast cell colony formation in semisolid culture with erythropoietin: a case report of acute poorly differentiated erythroid leukemia.

Science.gov (United States)

Tomonaga, M; Jinnai, I; Tagawa, M; Amenomori, T; Nishino, K; Yao, E; Nonaka, H; Kuriyama, K; Yoshida, Y; Matsuo, T

1987-02-01

The bone marrow of a patient with acute undifferentiated leukemia developed unique colonies after a 14-day culture in erythropoietin (EPO)-containing methylcellulose. The colonies consisted of 20 to 200 nonhemoglobinized large blast cells. Cytogenetic analysis of single colonies revealed hypotetraploid karyotypes with several marker chromosomes that were identical to those found in directly sampled bone marrow. The concurrently formed erythroid bursts showed only normal karyotypes. No leukemic colony formation was observed in other culture systems with either colony-stimulating activity (CSA) or phytohemagglutinin-stimulated leukocyte-conditioned medium (PHA-LCM). The leukemic colonies exhibited a complete EPO-dose dependency similar to that of the patient's normal BFU-E. Although cytochemical and immunologic marker studies of the bone marrow cells failed to clarify the cell lineage of the leukemic cells with extraordinarily large cell size, ultrastructural study revealed erythroid differentiation such as siderosome formation in the cytoplasm and ferritin particles in the rhophecytosis invaginations. These findings indicate that the patient had poorly differentiated erythroid leukemia and that some of the clonogenic cells might respond to EPO in vitro. Corresponding to this biological feature, the leukemic cells were markedly decreased in number in response to repeated RBC transfusions, and partial remission was obtained. These observations suggest that erythroid leukemia distinct from erythroleukemia (M6) with a myeloblastic component, can develop as a minor entity of human acute leukemia.

Hematopoietic stem cells can be separated from leukemic cells in a subgroup of adult acute lymphoblastic leukemia patients.

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Wang, Wenwen; Foerner, Elena; Buss, Eike; Jauch, Anna; Eckstein, Volker; Wuchter, Patrick; Ho, Anthony D; Lutz, Christoph

2017-06-01

In B-cell acute lymphoblastic leukemia (B-ALL) separation of normal hematopoietic stem cells (HSC) has so far been limited to a subgroup of patients. As aldehyde dehydrogenase (ALDH)-activity is enriched in various stem cells we investigated its value for HSC isolation in adult B-ALL. Based on ALDH-activity patients could be stratified in ALDH-numerous (≥1.9% ALDH +  cells) and ALDH-rare (cells) cases. In ALDH-rare B-ALL clonal-marker negative HSC could be separated by the CD34 + CD38 - ALDH +  phenotype, whereas this separation was not possible in ALDH-numerous B-ALL. Functional analysis confirmed the HSC-potential of isolated cells, which were uniformly CD19-negative. However, addition of ALDH-activity further improved HSC-purity. In summary, we provide a method to separate functionally normal HSC from leukemic cells in a subgroup of B-ALL patients that can be identified prospectively. This protocol thereby facilitates comparative analyses of matched HSC and leukemic cells in order to improve our understanding of leukemia evolution.

BCR/ABL downregulates DNA-PK(CS)-dependent and upregulates backup non-homologous end joining in leukemic cells.

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Poplawski, Tomasz; Blasiak, Janusz

2010-06-01

Non-homologous end joining (NHEJ) and homologous recombination repair (HRR) are the main mechanisms involved in the processing of DNA double strand breaks (DSBs) in humans. We showed previously that the oncogenic tyrosine kinase BCR/ABL stimulated DSBs repair by HRR. To evaluate the role of BCR/ABL in DSBs repair by NHEJ we examined the ability of leukemic BCR/ABL-expressing cell line BV173 to repair DNA damage induced by two DNA topoisomerase II inhibitors: etoposide and sobuzoxane. DNA lesions induced by sobuzoxane are repaired by a NHEJ pathway which is dependent on the catalytic subunit of protein kinase dependent on DNA (DNA-PK(CS); D-NHEJ), whereas damage evoked by etoposide are repaired by two distinct NHEJ pathways, dependent on or independent of DNA-PK(CS) (backup NHEJ, B-NHEJ). Cells incubated with STI571, a highly specific inhibitor of BCR/ABL, displayed resistance to these agents associated with an accelerated kinetics of DSBs repair, as measured by the neutral comet assay and pulsed field gel electrophoresis. However, in a functional NHEJ assay, cells preincubated with STI571 repaired DSBs induced by a restriction enzyme with a lower efficacy than without the preincubation and addition of wortmannin, a specific inhibitor of DNA-PK(CS), did not change efficacy of the NHEJ reaction. We suggest that BCR/ABL switch on B-NHEJ which is more error-prone then D-NHEJ and in such manner contribute to the increase of the genomic instability of leukemic cells.

Leukemic meningitis involving the cauda equina: a case report

International Nuclear Information System (INIS)

Lee, Dong Hyun; Kim, Ho Kyun; Lee, Young Hwan

2008-01-01

The CNS involvement by leukemia may either be meningeal or parenchymal, although meningeal infiltration of leukemic cells, known as leukemic meningitis is more common. We report a case of leukemic meningitis involving the cauda equina in a patient with an acute lymphoblastic crisis which transformed from the chronic phase of chronic myeloid leukemia. An MR image revealed diffuse enlargement and peripheral ring enhancement of the nerve roots of the cauda equina

Leukemic meningitis involving the cauda equina: a case report

Energy Technology Data Exchange (ETDEWEB)

Lee, Dong Hyun; Kim, Ho Kyun; Lee, Young Hwan [School of Medicine, Catholic University of Daegu, Daegu (Korea, Republic of)

2008-07-15

The CNS involvement by leukemia may either be meningeal or parenchymal, although meningeal infiltration of leukemic cells, known as leukemic meningitis is more common. We report a case of leukemic meningitis involving the cauda equina in a patient with an acute lymphoblastic crisis which transformed from the chronic phase of chronic myeloid leukemia. An MR image revealed diffuse enlargement and peripheral ring enhancement of the nerve roots of the cauda equina.

NF-κB in T-cell Acute Lymphoblastic Leukemia: Oncogenic Functions in Leukemic and in Microenvironmental Cells

International Nuclear Information System (INIS)

Santos, Nuno R. dos; Ghezzo, Marinella N.; Silva, Ricardo C. da; Fernandes, Mónica T.

2010-01-01

Two main NF-κB signaling pathways, canonical and noncanonical, performing distinct functions in organisms have been characterized. Identification of mutations in genes encoding components of these NF-κB signaling pathways in lymphoid malignancies confirmed their key role in leukemogenesis. T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive malignancy of thymocytes that despite significant therapeutic advances can still be fatal. Although mutations in NF-κB genes have not been reported in T-ALL, NF-κB constitutive activation in human T-ALL and in acute T-cell leukemia mouse models has been observed. Although these studies revealed activation of members of both canonical and noncanonical NF-κB pathways in acute T-cell leukemia, only inhibition of canonical NF-κB signaling was shown to impair leukemic T cell growth. Besides playing an important pro-oncogenic role in leukemic T cells, NF-κB signaling also appears to modulate T-cell leukemogenesis through its action in microenvironmental stromal cells. This article reviews recent data on the role of these transcription factors in T-ALL and pinpoints further research crucial to determine the value of NF-κB inhibition as a means to treat T-ALL

NF-κB in T-cell Acute Lymphoblastic Leukemia: Oncogenic Functions in Leukemic and in Microenvironmental Cells

Energy Technology Data Exchange (ETDEWEB)

Santos, Nuno R. dos, E-mail: nrsantos@ualg.pt; Ghezzo, Marinella N.; Silva, Ricardo C. da; Fernandes, Mónica T. [IBB-Institute for Biotechnology and Bioengineering, Centre for Molecular and Structural Biomedicine (CBME), University of Algarve, Campus de Gambelas, 8005-139 Faro (Portugal)

2010-11-05

Two main NF-κB signaling pathways, canonical and noncanonical, performing distinct functions in organisms have been characterized. Identification of mutations in genes encoding components of these NF-κB signaling pathways in lymphoid malignancies confirmed their key role in leukemogenesis. T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive malignancy of thymocytes that despite significant therapeutic advances can still be fatal. Although mutations in NF-κB genes have not been reported in T-ALL, NF-κB constitutive activation in human T-ALL and in acute T-cell leukemia mouse models has been observed. Although these studies revealed activation of members of both canonical and noncanonical NF-κB pathways in acute T-cell leukemia, only inhibition of canonical NF-κB signaling was shown to impair leukemic T cell growth. Besides playing an important pro-oncogenic role in leukemic T cells, NF-κB signaling also appears to modulate T-cell leukemogenesis through its action in microenvironmental stromal cells. This article reviews recent data on the role of these transcription factors in T-ALL and pinpoints further research crucial to determine the value of NF-κB inhibition as a means to treat T-ALL.

Apoptosis induction in MV4-11 and K562 human leukemic cells by Pereskia sacharosa (Cactaceae) leaf crude extract.

Science.gov (United States)

Asmaa, Mat Jusoh Siti; Al-Jamal, Hamid Ali Nagi; Ang, Cheng Yong; Asan, Jamaruddin Mat; Seeni, Azman; Johan, Muhammad Farid

2014-01-01

Pereskia sacharosa is a genus of cacti widely used in folk medicine for cancer-related treatment. Anti-proliferative effects have been studied in recent years against colon, breast, cervical and lung cancer cell lines, with promising results. We here extended study of anti-proliferative effects to a blood malignancy, leukemia. Two leukemic cell lines, MV4-11 (acute myeloid leukemia) and K562 (chronic myeloid leukemia), were studied. IC50 concentrations were determined and apoptosis and cell cycle regulation were studied by flow cytometric analysis. The expression of apoptosis and cell-cycle related regulatory proteins was assessed by Western blotting. P sacharosa inhibited growth of MV4-11 and K562 cells in a dose-dependent manner. The mode of cell death was via induction of intrinsic apoptotic pathways and cell cycle arrest. There was profound up-regulation of cytochrome c, caspases, p21 and p53 expression and repression of Akt and Bcl-2 expression in treated cells. These results suggest that P sacharosa induces leukemic cell death via apoptosis induction and changes in cell cycle checkpoint, thus deserves further study for anti-leukemic potential.

Effect of dioxin on normal and leukemic human hematopoietic cells

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Lambertenghi-Deliliers, G.; Soligo, D. [Univ. degli Studi, Milan (Italy). Dipt. die Ematologia, Ospedale Maggiore Policlinico IRCCS; Fracchiolla, N.S. [Ospedale Maggiore Policlinico IRCCS, Milan (Italy). Dipt. di Ematologia; Servida, F. [Fondazione Matarelli, Milan (Italy); Bertazzi, P.A. [Istituti Clinici di Perfezionamento, Milan (Italy). Dipt. di Medicina del Lavoro

2004-09-15

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) arises from chlorination of phenolic substrates or from partial combustion of organic materials in the presence of chlorine sources. TCDD has a large number of biological effects such as long-lasting skin disease, cardiovascular disease, diabete and cancer. TCDD is the prototypical agonist of the aryl hydrocarbon receptor (AhR), a member of the erb-A family that also includes the receptors for steroids, thyroid hormones, peroxisome proliferators and retinoids. When bound to dioxin, the AhR can bind to DNA and alter the expression of some genes including cytokines and growth factors. In this study, we analyzed the effect of escalating doses of TCDD on human CD34{sup +} progenitor cells from the leukapheresis of normal donors stimulated with G-CSF as well as the human myeloid leukemic cell lines HL60 (promyelocytic leukemia) and K562 (chronic myelogenous leukemia). The possible specific modulation of gene expression induced by the TCDD exposure was then tested by means of microarray analyses.

Leukemic meningitis in a patient with hairy cell leukemia. A case report

International Nuclear Information System (INIS)

Wolfe, D.W.; Scopelliti, J.A.; Boselli, B.D.

1984-01-01

Central nervous system involvement has not previously been described in patients with hairy cell leukemia (HCL). A patient is reported who presented with meningeal involvement as his initial symptom of HCL. Diagnosis was established by morphologic and cytochemical studies of his cerebrospinal fluid (CSF) and bone marrow. Treatment with whole-brain irradiation and intrathecal chemotherapy was successful in clearing leukemic cells from the CSF with resolution of symptoms

ROLE OF LEUKEMIC STEM CELLS IN THE CHRONIC MYELOID LEUKEMIA PATHOGENESIS

Directory of Open Access Journals (Sweden)

Sviezhentseva IO

2016-09-01

in the genes of kinase domains, transcription factors and tumor suppressors (genes of growth factors FLT3, C-KIT, genes K-RAS and N-RAS, mutations in genes STAT5A, TP53, AML1, RB1, MYC, p16 / NK4a, ENV1. Now the most important role in LSK biology research takes studying of signaling cascades involved in the processes of cell activity. This key molecule of cell signaling pathways can become targeted agents that may be used for the elimination of LSC from the patient bone marrow. However, it is necessary to distinguish the molecular cascades that are inherent to all bone marrow stem cells from LSC specific intracellular signal transmittors. Common to the LSC and HSC are the following signaling pathways: Wnt/β-catenin, Sonic Hedgehog and Noch signaling pathways. Moreover, there are signaling cascades that are specific only for LSC. They are charecterized by the exclusive expression of Alox5, AHI-1 and NFκB genes. In addition, the LSC are also characterized by the increased expression of AVSV-1 and ABCG-2 transporters, providing the evacuation of the cell chemotherapeutic drugs. LSC are characterized by the decreased expression of Oct-4, which ensures the supply of drugs to cells. The article also highlights the key therapeutic tactics that can be used to eliminate the recurrence of CML associated with the presence of LSC, which remain at rest for a long time, in the bone marrow of patients. The first tactic is elimination of LSC using the targeted drugs that operate solely on the target molecule in leukemic cells. The second approach is a direct administration of drugs to a patient that could promote a permanent state of rest for LSC in order to prevent relapses.

NKp46 identifies an NKT cell subset susceptible to leukemic transformation in mouse and human

Science.gov (United States)

Yu, Jianhua; Mitsui, Takeki; Wei, Min; Mao, Hsiaoyin; Butchar, Jonathan P.; Shah, Mithun Vinod; Zhang, Jianying; Mishra, Anjali; Alvarez-Breckenridge, Christopher; Liu, Xingluo; Liu, Shujun; Yokohama, Akihiko; Trotta, Rossana; Marcucci, Guido; Benson, Don M.; Loughran, Thomas P.; Tridandapani, Susheela; Caligiuri, Michael A.

2011-01-01

IL-15 may have a role in the development of T cell large granular lymphocyte (T-LGL) or NKT leukemias. However, the mechanisms of action and the identity of the cell subset that undergoes leukemic transformation remain elusive. Here we show that in both mice and humans, NKp46 expression marks a minute population of WT NKT cells with higher activity and potency to become leukemic. Virtually 100% of T-LGL leukemias in IL-15 transgenic mice expressed NKp46, as did a majority of human T-LGL leukemias. The minute NKp46+ NKT population, but not the NKp46– NKT population, was selectively expanded by overexpression of endogenous IL-15. Importantly, IL-15 transgenic NKp46– NKT cells did not become NKp46+ in vivo, suggesting that NKp46+ T-LGL leukemia cells were the malignant counterpart of the minute WT NKp46+ NKT population. Mechanistically, NKp46+ NKT cells possessed higher responsiveness to IL-15 in vitro and in vivo compared with that of their NKp46– NKT counterparts. Furthermore, interruption of IL-15 signaling using a neutralizing antibody could prevent LGL leukemia in IL-15 transgenic mice. Collectively, our data demonstrate that NKp46 identifies a functionally distinct NKT subset in mice and humans that appears to be directly susceptible to leukemic transformation when IL-15 is overexpressed. Thus, IL-15 signaling and NKp46 may be useful targets in the treatment of patients with T-LGL or NKT leukemia. PMID:21364281

Resveratrol protects leukemic cells against cytotoxicity induced by proteasome inhibitors via induction of FOXO1 and p27Kip1

International Nuclear Information System (INIS)

Niu, Xiao-Fang; Liu, Bao-Qin; Du, Zhen-Xian; Gao, Yan-Yan; Li, Chao; Li, Ning; Guan, Yifu; Wang, Hua-Qin

2011-01-01

It was reported recently that resveratrol could sensitize a number of cancer cells to the antitumoral effects of some conventional chemotherapy drugs. The current study was designed to investigate whether resveratrol could sensitize leukemic cells to proteasome inhibitors. Leukemic cells were treated with MG132 alone or in combination with resveratrol. Cell viability was investigated using MTT assay, and induction of apoptosis and cell cycle distribution was measured using flow cytometry. Western blot and real-time RT-PCR were used to investigate the expression of FOXO1 and p27 Kip1 . CHIP was performed to investigate the binding of FOXO1 to the p27 Kip1 promoter. Resveratrol strongly reduced cytotoxic activities of proteasome inhibitors against leukemic cells. MG132 in combination with resveratrol caused cell cycle blockade at G1/S transition via p27 Kip1 accumulation. Knockdown of p27 Kip1 using siRNA dramatically attenuated the protective effects of resveratrol on cytotoxic actions of proteasome inhibitors against leukemic cells. Resveratrol induced FOXO1 expression at the transcriptional level, while MG132 increased nuclear distribution of FOXO1. MG132 in combination with resveratrol caused synergistic induction of p27 Kip1 through increased recruitment of FOXO1 on the p27 Kip1 promoter. Resveratrol may have the potential to negate the cytotoxic effects of proteasome inhibitors via regulation of FOXO1 transcriptional activity and accumulation of p27 Kip1

Effects of granulocyte-macrophage colony-stimulating factor and interleukin 6 on the growth of leukemic blasts in suspension culture.

Science.gov (United States)

Tsao, C J; Cheng, T Y; Chang, S L; Su, W J; Tseng, J Y

1992-05-01

We examined the stimulatory effects of recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin 6 (IL)-6 on the in vitro proliferation of leukemic blast cells from patients with acute leukemia. Bone marrow or peripheral blood leukemic blast cells were obtained from 21 patients, including 14 cases of acute myeloblastic leukemia (AML), four cases of acute lymphoblastic leukemia (ALL), two cases of acute undifferentiated leukemia, and one case of acute mixed-lineage leukemia. The proliferation of leukemic blast cells was evaluated by measuring the incorporation of 3H-thymidine into cells incubated with various concentrations of cytokines for 3 days. GM-CSF stimulated the DNA synthesis (with greater than 2.0 stimulation index) of blast cells in 9 of 14 (64%) AML cases, two cases of acute undifferentiated leukemia and one case of acute mixed-lineage leukemia. Only two cases of AML blasts responded to IL-6 to grow in the short-term suspension cultures. GM-CSF and IL-6 did not display a synergistic effect on the growth of leukemic cells. Moreover, GM-CSF and IL-6 did not stimulate the proliferation of ALL blast cells. Binding study also revealed the specific binding of GM-CSF on the blast cells of acute undifferentiated leukemia and acute mixed-lineage leukemia. Our results indicated that leukemic blast cells of acute undifferentiated leukemia and acute mixed-lineage leukemia possessed functional GM-CSF receptors.

Musashi2 modulates K562 leukemic cell proliferation and apoptosis involving the MAPK pathway

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Zhang, Huijuan; Tan, Shi; Wang, Juan; Chen, Shana; Quan, Jing; Xian, Jingrong; Zhang, Shuai shuai; He, Jingang; Zhang, Ling, E-mail: lingzhang@cqmu.edu.cn

2014-01-01

The RNA-binding protein Musashi2 (Msi2) has been identified as a master regulator within a variety of stem cell populations via the regulation of translational gene expression. A recent study has suggested that Msi2 is strongly expressed in leukemic cells of acute myeloid leukemia patients, and elevated Msi2 is associated with poor prognosis. However, the potential role of Msi2 in leukemogenesis is still not well understood. Here, we investigated the effect of Msi2 knockdown on the biological properties of leukemic cells. High expression of Msi2 was found in K562 and KG-1a leukemic cell lines, and low expression was observed in the U937 cell line. We transduced K562 cells with two independent adenoviral shRNA vectors targeting Msi2 and confirmed knockdown of Msi2 at the mRNA and protein levels. Msi2 silencing inhibited cell growth and caused cell cycle arrest by increasing the expression of p21 and decreasing the expression of cyclin D1 and cdk2. In addition, knockdown of Msi2 promoted cellular apoptosis via the upregulation of Bax and downregulation of Bcl-2 expression. Furthermore, Msi2 knockdown resulted in the inactivation of the ERK/MAPK and p38/MAPK pathways, but no remarkable change in p-AKT was observed. These data provide evidence that Msi2 plays an important role in leukemogenesis involving the MAPK signaling pathway, which indicates that Msi2 may be a novel target for leukemia treatment. - Highlights: • Knockdown of Msi2 inhibited K562 cell growth and arrested cell cycle progression. • Knockdown of Msi2 induced K562 cell apoptosis via the regulation of Bax and Bcl-2. • The MAPK pathway was involved in the process of Msi2-mediated leukemogenesis. • Our data indicate that Msi2 is a potential new target for leukemia treatment.

Inhibitory effect of turmeric curcuminoids on FLT3 expression and cell cycle arrest in the FLT3-overexpressing EoL-1 leukemic cell line.

Science.gov (United States)

Tima, Singkome; Ichikawa, Hideki; Ampasavate, Chadarat; Okonogi, Siriporn; Anuchapreeda, Songyot

2014-04-25

Leukemia is a hematologic malignancy with a frequent incidence and high mortality rate. Previous studies have shown that the FLT3 gene is overexpressed in leukemic blast cells, especially in acute myeloid leukemia. In this study, a commercially available curcuminoid mixture (1), pure curcumin (2), pure demethoxycurcumin (3), and pure bisdemethoxycurcumin (4) were investigated for their inhibitory effects on cell growth, FLT3 expression, and cell cycle progression in an FLT3-overexpressing EoL-1 leukemic cell line using an MTT assay, Western blotting, and flow cytometry, respectively. The mixture (1) and compounds 2-4 demonstrated cytotoxic effects with IC50 values ranging from 6.5 to 22.5 μM. A significant decrease in FLT3 protein levels was found after curcuminoid treatment with IC20 doses, especially with mixture 1 and compound 2. In addition, mixture 1 and curcumin (2) showed activity on cell cycle arrest at the G0/G1 phase and decreased the FLT3 and STAT5A protein levels in a dose-dependent manner. Compound 2 demonstrated the greatest potential for inhibiting cell growth, cell cycle progression, and FLT3 expression in EoL-1 cells. This investigation has provided new findings regarding the effect of turmeric curcuminoids on FLT3 expression in leukemic cells.

IN SILICO MODELLING OF CYTOTOXIC BEHAVIOUR OF ANTI-LEUKEMIC COMPOUNDS ON HL-60 CELL LINE

Directory of Open Access Journals (Sweden)

David Ebuka Arthur

2016-05-01

Full Text Available This research employs multiple linear regression technique in the modelling of some potent anti-leukemic compounds using paDEL molecular descriptor software calculator, to identify the best relationship between the chemical structure and toxicities of the anticancer datasets against some leukemic cell lines (HL-60. Statistical parameters such as Q2 and R2pred (test set were computed to validate the strength of the model, while Williams plot was used to assess its applicability domain. The mean effects of the molecular descriptors in the models were calculated to illuminate the principal properties of the molecules responsible for their cytotoxicity.

Inhibition of time-dependent enhancement of amino acid transport by leukemic leukocytes: a possible index of the sensitivity of cells to drugs

Energy Technology Data Exchange (ETDEWEB)

Frengley, P A; Peck, W A; Lichtman, M A

1975-01-01

Leukemic leukocytes increase their rates of alpha aminoisobutyric acid (AIB) accumulation when incubated for prolonged periods in amino acid deficient media. The time-dependent increase was prevented by concurrent exposure of cells to cycloheximide or actinomycin D in vitro. In addition, the increase in AIB uptake was not present in leukemic blasts studied in vitro when the cells were obtained from subjects with acute myeloblastic leukemia who had received antileukemic therapy. Cortisol added to cell suspensions in vitro inhibited the development of time-dependent increases in AIB uptake in lymphoid cells, but accentuated the process slightly in myeloblasts. Cortisol administered to a subject with CLL by infusion reduced the time-dependent increase in AIB uptake by CLL cells subsequently studied in vitro. These data indicate that the time-dependent increase in AIB uptake may be a means of testing the sensitivity of leukemic cells to drugs.

NO-donating aspirin inhibits the growth of leukemic Jurkat cells and modulates β-catenin expression

International Nuclear Information System (INIS)

Nath, Niharika; Labaze, Georges; Rigas, Basil; Kashfi, Khosrow

2004-01-01

β-Catenin has been implicated in leukemic cell proliferation. We compared the effects of aspirin (ASA) and the ortho, meta, and para positional isomers of NO-donating aspirin (NO-ASA) on cell growth and β-catenin expression in human Jurkat T leukemic cells. Cell growth inhibition was strong: IC 50 for p-, o-, and m- were 20 ± 1.6 (mean ± SEM), 15 ± 1.5, and 200 ± 12 μM, respectively, in contrast to that of ASA (3200 ± 375 μM). The para isomer of NO-ASA degraded β-catenin in a dose- and time-dependent manner coinciding with increasing expression of activated caspase-3. The caspase inhibitor ZVAD blocked β-catenin cleavage by p-NO-ASA and partially reversed cell growth inhibition by p-NO-ASA but not that by ASA. A denitrated analog of p-NO-ASA did not degrade β-catenin indicating the importance of the NO-donating moiety. Our findings suggest that NO-ASA merits further study as an agent against leukemia

Expression of MIF and CD74 in leukemic cell lines: correlation to DR expression destiny.

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Georgouli, Mirella; Papadimitriou, Lina; Glymenaki, Maria; Patsaki, Valia; Athanassakis, Irene

2016-06-01

Invariant chain (Ii) or CD74 is a non-polymorphic glycoprotein, which apart from its role as a chaperone dedicated to MHCII molecules, is known to be a high-affinity receptor for macrophage migration inhibitory factor (MIF). The present study aimed to define the roles of CD74 and MIF in the immune surveillance escape process. Towards this direction, the cell lines HL-60, Raji, K562 and primary pre-B leukemic cells were examined for expression and secretion of MIF. Flow cytometry analysis detected high levels of MIF and intracellular/membrane CD74 expression in all leukemic cells tested, while MIF secretion was shown to be inversely proportional to intracellular HLA-DR (DR) expression. In the MHCII-negative cells, IFN-γ increased MIF expression and induced its secretion in HL-60 and K562 cells, respectively. In K562 cells, CD74 (Iip33Iip35) was shown to co-precipitate with HLA-DOβ (DOβ), inhibiting thus MIF or DR binding. Induced expression of DOα in K562 (DOα-DOβ+) cells in different transfection combinations decreased MIF expression and secretion, while increasing surface DR expression. Thus, MIF could indeed be part of the antigen presentation process.

Targeting Toll-like receptor 7/8 enhances uptake of apoptotic leukemic cells by monocyte-derived dendritic cells but interferes with subsequent cytokine-induced maturation.

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van den Ancker, Willemijn; van Luijn, Marvin M; Ruben, Jurjen M; Westers, Theresia M; Bontkes, Hetty J; Ossenkoppele, Gert J; de Gruijl, Tanja D; van de Loosdrecht, Arjan A

2011-01-01

Therapeutic vaccination with dendritic cells (DC) is an emerging investigational therapy for eradication of minimal residual disease in acute myeloid leukemia. Various strategies are being explored in manufacturing DC vaccines ex vivo, e.g., monocyte-derived DC (MoDC) loaded with leukemia-associated antigens (LAA). However, the optimal source of LAA and the choice of DC-activating stimuli are still not well defined. Here, loading with leukemic cell preparations (harboring both unknown and known LAA) was explored in combination with a DC maturation-inducing cytokine cocktail (CC; IL-1β, IL-6, TNF-α, and PGE(2)) and Toll-like receptor ligands (TLR-L) to optimize uptake. Since heat shock induced apoptotic blasts were more efficiently taken up than lysates, we focused on uptake of apoptotic leukemic cells. Uptake of apoptotic blast was further enhanced by the TLR7/8-L R848 (20-30%); in contrast, CC-induced maturation inhibited uptake. CC, and to a lesser extent R848, enhanced the ability of MoDC to migrate and stimulate T cells. Furthermore, class II-associated invariant chain peptide expression was down-modulated after R848- or CC-induced maturation, indicating enhanced processing and presentation of antigenic peptides. To improve both uptake and maturation, leukemic cells and MoDC were co-incubated with R848 for 24 h followed by addition of CC. However, this approach interfered with CC-mediated MoDC maturation as indicated by diminished migratory and T cell stimulatory capacity, and the absence of IL-12 production. Taken together, our data demonstrate that even though R848 improved uptake of apoptotic leukemic cells, the sequential use of R848 and CC is counter-indicated due to its adverse effects on MoDC maturation.

Correlation of total body potassium and leukemic cell mass in patients with chronic lymphocytic leukemia

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Chandra, P.; Sawitsky, A.; Chanana, A.D.; Chikkappa, G.; Cohn, S.H.; Rai, K.R.; Cronkity, E.P.

1979-01-01

Total body leukemic mass in patients with chronic lymphocytic leukemia (CLL) was measured by quantitation of total body potassium (TBK) with a whole-body counter. In addition, the predicted normal total body potassium (Kp) for each patient was calculated from an empirically derived relationship involving height, weight age, and sex. Both the absolute TBK and the relative excess of total body potassium (TBK/Kp) were related to the stage of disease. Patients in the early stages of CLL were found to have lower TBK and TBK/Kp than patients in the late stages of disease. Both of these parameters increased with the successively advanced stages of the disease. The clinically monitored reduction of leukemic cell mass following therapy was accompanied by reductions in TBK and TBK/Kp. Data presented support the notion that TBK/Kp is a useful indicator of the total body leukemic mass. Futhermore, the results of these studies quantitatively validate the proposed clinical staging system for CLL. Quantitation of TBK by a whole-body counter is an accurate and noninvasive procedure and does not require administration of isotopes

[Expression of c-MPL in leukemic stem cells from acute myeloid leukemia patients].

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Yu, Pei; Qiu, Shao-Wei; Rao, Qing; Lin, Dong; Xing, Hai-Yan; Tang, Ke-Jing; Tian, Zheng; Wang, Min; Wang, Jian-Xiang

2012-10-01

This study was aimed to investigate the expression of c-MPL in acute myeloid leukemia (AML) and the correlation of the c-MPL expression with CD34 and CD38, so as to define the expression of c-MPL in leukemic stem cells. The expression levels of CD34, CD38 and c-MPL were detected by flow cytometry in bone marrow cells from 29 newly diagnosed AML patients. The relationship of c-MPL positive cell ratio with clinical parameters and correlation of c-MPL with CD34 and CD38 expression in AML patients were analyzed. The results showed that expression level of c-MPL in AML patients was significantly higher than that of normal controls (P MPL did not correlate with age, sex, white blood cell count, AML1-ETO fusion gene and remission after chemotherapy, but the expression of c-MPL in M2 and M5 patients was higher than that of normal control (P MPL in CD34 positive AML patients was obviously higher than that in CD34 negative AML patients (P MPL was significantly higher expressed in CD34(+) cells than that in CD34(-) cells (P MPL expression was not significantly different between CD34(+)CD38(-) and CD34(+)CD38(-) cell groups. Positive correlation between c-MPL and CD34 expression was observed (r = 0.380, P = 0.042). It is concluded that expression of c-MPL is higher in AML patients, and positively correlates with the expression level of CD34. The c-MPL expresses in leukemic stem cells.

Aberrant methylation of the M-type phospholipase A2 receptor gene in leukemic cells

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Menschikowski, Mario; Platzbecker, Uwe; Hagelgans, Albert; Vogel, Margot; Thiede, Christian; Schönefeldt, Claudia; Lehnert, Renate; Eisenhofer, Graeme; Siegert, Gabriele

2012-01-01

The M-type phospholipase A2 receptor (PLA2R1) plays a crucial role in several signaling pathways and may act as tumor-suppressor. This study examined the expression and methylation of the PLA2R1 gene in Jurkat and U937 leukemic cell lines and its methylation in patients with myelodysplastic syndrome (MDS) or acute leukemia. Sites of methylation of the PLA2R1 locus were identified by sequencing bisulfite-modified DNA fragments. Methylation specific-high resolution melting (MS-HRM) analysis was then carried out to quantify PLA2R1 methylation at 5-CpG sites identified with differences in methylation between healthy control subjects and leukemic patients using sequencing of bisulfite-modified genomic DNA. Expression of PLA2R1 was found to be completely down-regulated in Jurkat and U937 cells, accompanied by complete methylation of PLA2R1 promoter and down-stream regions; PLA2R1 was re-expressed after exposure of cells to 5-aza-2´-deoxycytidine. MS-HRM analysis of the PLA2R1 locus in patients with different types of leukemia indicated an average methylation of 28.9% ± 17.8%, compared to less than 9% in control subjects. In MDS patients the extent of PLA2R1 methylation significantly increased with disease risk. Furthermore, measurements of PLA2R1 methylation appeared useful for predicting responsiveness to the methyltransferase inhibitor, azacitidine, as a pre-emptive treatment to avoid hematological relapse in patients with high-risk MDS or acute myeloid leukemia. The study shows for the first time that PLA2R1 gene sequences are a target of hypermethylation in leukemia, which may have pathophysiological relevance for disease evolution in MDS and leukemogenesis

Novel quinazolinone MJ-29 triggers endoplasmic reticulum stress and intrinsic apoptosis in murine leukemia WEHI-3 cells and inhibits leukemic mice.

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Chi-Cheng Lu

Full Text Available The present study was to explore the biological responses of the newly compound, MJ-29 in murine myelomonocytic leukemia WEHI-3 cells in vitro and in vivo fates. We focused on the in vitro effects of MJ-29 on ER stress and mitochondria-dependent apoptotic death in WEHI-3 cells, and to hypothesize that MJ-29 might fully impair the orthotopic leukemic mice. Our results indicated that a concentration-dependent decrease of cell viability was shown in MJ-29-treated cells. DNA content was examined utilizing flow cytometry, whereas apoptotic populations were determined using annexin V/PI, DAPI staining and TUNEL assay. Increasing vital factors of mitochondrial dysfunction by MJ-29 were further investigated. Thus, MJ-29-provaked apoptosis of WEHI-3 cells is mediated through the intrinsic pathway. Importantly, intracellular Ca(2+ release and ER stress-associated signaling also contributed to MJ-29-triggered cell apoptosis. We found that MJ-29 stimulated the protein levels of calpain 1, CHOP and p-eIF2α pathways in WEHI-3 cells. In in vivo experiments, intraperitoneal administration of MJ-29 significantly improved the total survival rate, enhanced body weight and attenuated enlarged spleen and liver tissues in leukemic mice. The infiltration of immature myeloblastic cells into splenic red pulp was reduced in MJ-29-treated leukemic mice. Moreover, MJ-29 increased the differentiations of T and B cells but decreased that of macrophages and monocytes. Additionally, MJ-29-stimulated immune responses might be involved in anti-leukemic activity in vivo. Based on these observations, MJ-29 suppresses WEHI-3 cells in vitro and in vivo, and it is proposed that this potent and selective agent could be a new chemotherapeutic candidate for anti-leukemia in the future.

Ethyl acetate extract of Chinese medicinal herb Sarcandra glabra induces growth inhibition on human leukemic HL-60 cells, associated with cell cycle arrest and up-regulation of pro-apoptotic Bax/Bcl-2 ratio.

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Li, W Y; Chiu, Lawrence C M; Lam, W S; Wong, W Y; Chan, Y T; Ho, Y P; Wong, Elaine Y L; Wong, Y S; Ooi, Vincent E C

2007-02-01

Sarcandra glabra (Thunb.) Nakai, colloquially known as Caoshanhu, is a Chinese medicinal herb with reported anti-tumor, anti-inflammatory, anti-viral and non-specific immunoenhancing properties. Although the plant has been clinically used for treating a variety of diseases, its bioactive ingredients are largely unknown and its mode of action has never been investigated. In this study, the anti-tumor property of ethyl acetate (EA) extract of S. glabra was investigated by determining its in vitro growth-inhibitory effects on a panel of human cancer cell lines of different histotypes. Growth inhibition of the EA extract on the cancer cells seemed to be selective, and the leukemic HL-60 was found to be the most responsive after 48 h of treatment (IC50=58 microg/ml). Flow cytometric studies further illustrated that the extract might interfere with DNA replication and thus arrested the cell cycle at S phase in the leukemic cells, followed by DNA fragmentation and loss of phospholipid asymmetry in the plasma membrane after 72 h of treatment. Concurrently, the pro-apoptotic Bax/Bcl-2 ratio was also up-regulated by more than 178% of the control level. All these findings suggested that the extract had initiated apoptosis to kill the leukemic cells. Results from this pioneer study help to establish a scientific foundation for future research and development of the bioactive ingredients in EA extract of S. glabra as efficacious anti-cancer agents.

Leukemic transformation of donor spleen cells following their transplantation into supralethally irradiated mice with pre-existing viral leukemia. [X Radiation

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Kuhnert, P M; OKunewick, J P; Erhard, P

1974-01-01

Fialkow et al. previously reported leukemia induction in donor-type cells after treating patients for acute lymphoblastic leukemia with total-body irradiation and hematopoietic cell transplantation. Utilizing a murine model and paralleling their treatment protocol, we have documented that induction of leukemia can occur in normal donor cells transplanted into Rauscher viral leukemic mice at 0, 1 and 2 days after irradiation. The induction of leukemia in the grafted cells was verified by: the occurrence of splenomegaly; and secondary spleen cell transplants, whereby the secondary donors were transplanted mice still alive at 30 days and the secondary recipients were normal unirradiated mice. The spleen weights of the grafted leukemic mice were found to be significantly greater than those of the controls and all secondary recipients that received spleen cells from the primary grafted leukemic mice also died of leukemia. Verification that the regenerating hematopoietic tissue was from donor (males) and not host source (females) was accomplished by spleen chromosome preparations taken from randomly selected mice at 14 and at 30 days after cell transplantation. In these preparations, the Y chromosome was clearly distinguishable on the basis of size, shape, and differential staining. The data indicate that induction of leukemia after whole-body irradiation and hematopoietic cell transplantation can occur in immunologically matched donor cells when a viral agent is present and that the incidence of this induction is not affected by a time delay between irradiation and transplant.

Piperlongumine induces apoptosis and autophagy in leukemic cells through targeting the PI3K/Akt/mTOR and p38 signaling pathways.

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Wang, Hongfei; Wang, Yongqiang; Gao, Hongmei; Wang, Bing; Dou, Lin; Li, Yin

2018-02-01

Piperlongumine is an alkaloid compound extracted from Piper longum L. It is a chemical substance with various pharmacological effects and medicinal value, including anti-tumor, lipid metabolism regulatory, antiplatelet aggregation and analgesic properties. The present study aimed to understand whether piperlongumine induces the apoptosis and autophagy of leukemic cells, and to identify the mechanism involved. Cell viability and autophagy were detected using MTT, phenazine methyl sulfate and trypan blue exclusion assays. The apoptosis rate was calculated using flow cytometry. The protein expression levels of microtubule-associated protein 1A/1B-light chain 3, Akt and mechanistic target of rapamycin (mTOR) were measured using western blotting. The cell growth of leukemic cells was completely inhibited following treatment with piperlongumine, and marked apoptosis was also induced. Dead cells as a result of autophagy were stained using immunofluorescence and observed under a light microscope. Phosphoinositide 3-kinase (PI3K)/Akt/mTOR signaling was suppressed by treatment with piperlongumine, while p38 signaling and caspase-3 activity were induced by treatment with piperlongumine. It was concluded that piperlongumine induces apoptosis and autophagy in leukemic cells through targeting the PI3K/Akt/mTOR and p38 signaling pathways.

Cyclopentenyl cytosine induces apoptosis and increases cytarabine-induced apoptosis in a T-lymphoblastic leukemic cell-line

NARCIS (Netherlands)

Verschuur, A. C.; Brinkman, J.; van Gennip, A. H.; Leen, R.; Vet, R. J.; Evers, L. M.; Voûte, P. A.; van Kuilenburg, A. B.

2001-01-01

Cyclopentenyl cytosine (CPEC) is a nucleoside-analogue that decreases the concentrations of cytidine triphosphate (CTP) and deoxycytidine triphosphate (dCTP) in leukemic cells by inhibiting the enzyme CTP synthetase, resulting in a decreased synthesis of RNA and DNA. Low concentrations of dCTP

Properties of murine leukemia viruses produced by leukemic cells established from NIH Swiss mice with radiation-induced leukemia

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Okumoto, Masaaki; Nishikawa, Ryosuke; Takamori, Yasuhiko; Iwai, Yoshiaki; Iwai, Mineko [Radiation Center of Osaka Prefecture, Sakai (Japan); Imai, Shunsuke; Morimoto, Junji; Tsubura, Yoshihiko

1984-06-01

Three leukemic cell lines, designated NIH-RL1, NIH-RL2 and NFS-RL1, were established from spleen and thymuses of NIH Swiss and NFS mice with radiation-induced leukemia. The culture fluids of these cell lines contained RNA-dependent DNA polymerase (RDDP) activities associated with particles of buoyant density of 1.15-1.17 (g/cm/sup 3/). The divalent cation reqirement of these enzymes was characteristic for that of murine leukemia viruses. In competition radioimmunoassay, a major core protein, p30, was detected in culture fluid of each leukemic cell line. Competition curves of viral p30 produced by these cell lines revealed that these viruses were very similar to those of xenotropic viruses of NZB mice. These viruses were undetectable both by XC plaque assay using SC-1 cells as an indicator cell, and by mink S/sup +/L/sup -/ focus induction assay. These viruses also lacked productive infectivity to mink lung cells (CCL-64), and were nononcogenic in syngeneic mice when the viruses were intrathymically inoculated.

Positive /sup 111/In-granulocyte scintigraphy in a patient with focal leukemic blast cell infiltrations

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Syrjaelae, M; Remes, K; Paavonen, T; Liewendahl, K

1985-06-01

A patient with acute myeloid leukemia was investigated with /sup 111/In-granulocyte scintigraphy to reveal possible sites of infection. /sup 111/In-granulocytes accumulated in areas of leukemia blast cell infiltration leading to a false-positive scintigram. This possibility must be kept in mind when studying leukemic patients using labeled leukocytes.

Defective quorum sensing of acute lymphoblastic leukemic cells: evidence of collective behavior of leukemic populations as semi-autonomous aberrant ecosystems

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Patel, Sapan J; Dao, Su; Darie, Costel C; Clarkson, Bayard D

2016-01-01

Quorum sensing (QS) is a generic term used to describe cell-cell communication and collective decision making by bacterial and social insects to regulate the expression of specific genes in controlling cell density and other properties of the populations in response to nutrient supply or changes in the environment. QS mechanisms also have a role in higher organisms in maintaining homeostasis, regulation of the immune system and collective behavior of cancer cell populations. In the present study, we used a p190BCR-ABL driven pre-B acute lymphoblastic leukemia (ALL3) cell line derived from the pleural fluid of a terminally ill patient with ALL to test the QS hypothesis in leukemia. ALL3 cells don’t grow at low density (LD) in liquid media but grow progressively faster at increasingly high cell densities (HD) in contrast to other established leukemic cell lines that grow well at very low starting cell densities. The ALL3 cells at LD are poised to grow but shortly die without additional stimulation. Supernates of ALL3 cells (HDSN) and some other primary cells grown at HD stimulate the growth of the LD ALL3 cells without which they won’t survive. To get further insight into the activation processes we performed microarray analysis of the LD ALL3 cells after stimulation with ALL3 HDSN at days 1, 3, and 6. This screen identified several candidate genes, and we linked them to signaling networks and their functions. We observed that genes involved in lipid, cholesterol, fatty acid metabolism, and B cell activation are most up- or down-regulated upon stimulation of the LD ALL3 cells using HDSN. We also discuss other pathways that are differentially expressed upon stimulation of the LD ALL3 cells. Our findings suggest that the Ph+ ALL population achieves dominance by functioning as a collective aberrant ecosystem subject to defective quorum-sensing regulatory mechanisms. PMID:27429840

Analysis of myelomonocytic leukemic differentiation by a cell surface marker panel including a fucose-binding lectin from Lotus tetragonolobus.

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Elias, L; Van Epps, D E

1984-06-01

The fucose-binding lectin from Lotus tetragonolobus ( FBL -L) has been previously shown to bind specifically to normal cells of the myeloid and monocytic lineages. The purpose of this study was to explore the utility of fluoresceinated FBL -L as a leukemia differentiation marker in conjunction with a panel of other frequently used surface markers (Fc receptor, HLA-DR, OKM1, and antimonocyte antibody). FBL -L reacted with leukemic cells in 8/9 cases of clinically recognized acute myeloid leukemia, including myeloid blast crisis of chronic granulocytic leukemia, 3/3 cases of chronic phase chronic myelogenous leukemia, and in 2/7 cases of clinically undifferentiated acute leukemia. Correlations were noted between reactivity with FBL -L, and DR and Fc receptor expression. Among continuous cell lines, FBL -L bound with high intensity to a majority of HL-60 and U937 cells. The less well differentiated myeloblast cell lines, KG-1, KG1a , and HL-60 blast II, exhibited less FBL -L binding than HL-60 and U937. A moderate proportion of K562 cells exhibited low level binding of FBL -L. Several lymphoblastic cell lines exhibited a pattern of low intensity binding that was distinguishable from the high intensity binding pattern of the myeloblastic lines. FBL -L reactivity of U937 was enhanced by induction of differentiation with leukocyte conditioned medium, but not dimethylsulfoxide. Such treatments induced contrasting patterns of change of HL-60 and U937 when labeled with OKM1, alpha-Mono, and HLA-DR. These studies demonstrate the application of FBL -L to analysis and quantitation of myelomonocytic leukemic differentiation.

Leukemic Oral Manifestations and their Management.

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Francisconi, Carolina Favaro; Caldas, Rogerio Jardim; Oliveira Martins, Lazara Joyce; Fischer Rubira, Cassia Maria; da Silva Santos, Paulo Sergio

2016-01-01

Leukemia is the most common neoplastic disease of the white blood cells which is important as a pediatric malignancy. Oral manifestations occur frequently in leukemic patients and may present as initial evidence of the disease or its relapse. The symptoms include gingival enlargement and bleeding, oral ulceration, petechia, mucosal pallor, noma, trismus and oral infections. Oral lesions arise in both acute and chronic forms of all types of leukemia. These oral manifestations either may be the result of direct infiltration of leukemic cells (primary) or secondary to underlying thrombocytopenia, neutropenia, or impaired granulocyte function. Despite the fact that leukemia has long been known to be associated with oral lesions, the available literature on this topic consists mostly of case reports, without data summarizing the main oral changes for each type of leukemia. Therefore, the present review aimed at describing oral manifestations of all leukemia types and their dental management. This might be useful in early diagnosis, improving patient outcomes.

The cyclin-dependent kinase inhibitor 5, 6-dichloro-1-beta-D-ribofuranosylbenzimidazole induces nongenotoxic, DNA replication-independent apoptosis of normal and leukemic cells, regardless of their p53 status

International Nuclear Information System (INIS)

Turinetto, Valentina; Porcedda, Paola; Orlando, Luca; De Marchi, Mario; Amoroso, Antonio; Giachino, Claudia

2009-01-01

Current chemotherapy of human cancers focuses on the DNA damage pathway to induce a p53-mediated cellular response leading to either G1 arrest or apoptosis. However, genotoxic treatments may induce mutations and translocations that result in secondary malignancies or recurrent disease. In addition, about 50% of human cancers are associated with mutations in the p53 gene. Nongenotoxic activation of apoptosis by targeting specific molecular pathways thus provides an attractive therapeutic approach. Normal and leukemic cells were evaluated for their sensitivity to 5, 6-dichloro-1-beta-D-ribofuranosylbenzimidazole (DRB) through cell viability and caspase activation tests. The apoptotic pathway induced by DRB was analysed by immunfluorescence and immunoblot analysis. H2AX phosphorylation and cell cycle analysis were performed to study the dependance of apoptosis on DNA damage and DNA replication, respectively. To investigate the role of p53 in DRB-induced apoptosis, specific p53 inhibitors were used. Statistical analysis on cell survival was performed with the test of independence. Here we report that DRB, an inhibitor of the transcriptional cyclin-dependent kinases (CDKs) 7 and 9, triggers DNA replication-independent apoptosis in normal and leukemic human cells regardless of their p53 status and without inducing DNA damage. Our data indicate that (i) in p53-competent cells, apoptosis induced by DRB relies on a cytosolic accumulation of p53 and subsequent Bax activation, (ii) in the absence of p53, it may rely on p73, and (iii) it is independent of ATM and NBS1 proteins. Notably, even apoptosis-resistant leukemic cells such as Raji were sensitive to DRB. Our results indicate that DRB represents a potentially useful cancer chemotherapeutic strategy that employs both the p53-dependent and -independent apoptotic pathways without inducing genotoxic stress, thereby decreasing the risk of secondary malignancies

Human Leukemic Cells performing Oxidative Phosphorylation (OXPHOS Generate an Antioxidant Response Independently of Reactive Oxygen species (ROS Production

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Abrar Ul Haq Khan

2016-01-01

Full Text Available Tumor cell metabolism is altered during leukemogenesis. Cells performing oxidative phosphorylation (OXPHOS generate reactive oxygen species (ROS through mitochondrial activity. To limit the deleterious effects of excess ROS, certain gene promoters contain antioxidant response elements (ARE, e.g. the genes NQO-1 and HO-1. ROS induces conformational changes in KEAP1 and releases NRF2, which activates AREs. We show in vitro and in vivo that OXPHOS induces, both in primary leukemic cells and cell lines, de novo expression of NQO-1 and HO-1 and also the MAPK ERK5 and decreases KEAP1 mRNA. ERK5 activates the transcription factor MEF2, which binds to the promoter of the miR-23a–27a–24-2 cluster. Newly generated miR-23a destabilizes KEAP1 mRNA by binding to its 3′UTR. Lower KEAP1 levels increase the basal expression of the NRF2-dependent genes NQO-1 and HO-1. Hence, leukemic cells performing OXPHOS, independently of de novo ROS production, generate an antioxidant response to protect themselves from ROS.

Involvement of CD147 on multidrug resistance through the regulation of P-glycoprotein expression in K562/ADR leukemic cell line

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Aoranit Somno

2016-01-01

Full Text Available The relationship between P-gp and CD147 in the regulation of MDR in leukemic cells has not been reported. This study aimed to investigate the correlation between CD147 and P-gp in the regulation of drug resistance in the K562/ADR leukemic cell line. The results showed that drug-resistant K562/ADR cells expressed significantly higher P-gp and CD147 levels than drug-free K562/ADR cells. To determine the regulatory effect of CD147 on P-gp expression, anti-CD147 antibody MEM-M6/6 significantly decreased P-gp and CD147 mRNA and protein levels. This is the first report to show that CD147 mediates MDR in leukemia through the regulation of P-gp expression.

Dendritic cells (DCs) can be successfully generated from leukemic blasts in individual patients with AML or MDS: an evaluation of different methods.

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Kremser, Andreas; Dressig, Julia; Grabrucker, Christine; Liepert, Anja; Kroell, Tanja; Scholl, Nina; Schmid, Christoph; Tischer, Johanna; Kufner, Stefanie; Salih, Helmut; Kolb, Hans Jochem; Schmetzer, Helga

2010-01-01

Myeloid-leukemic cells (AML, MDS, CML) can be differentiated to leukemia-derived dendritic cell [DC (DCleu)] potentially presenting the whole leukemic antigen repertoire without knowledge of distinct leukemia antigens and are regarded as promising candidates for a vaccination strategy. We studied the capability of 6 serum-free DC culture methods, chosen according to different mechanisms, to induce DC differentiation in 137 cases of AML and 52 cases of MDS. DC-stimulating substances were cytokines ("standard-medium", "MCM-Mimic", "cytokine-method"), bacterial lysates ("Picibanil"), double-stranded RNA ["Poly (I:C)"] or a cytokine bypass method ("Ca-ionophore"). The quality/quantity of DC generated was estimated by flow cytometry studying (co) expressions of "DC"antigens, costimulatory, maturation, and blast-antigens. Comparing these methods on average 15% to 32% DC, depending on methods used, could be obtained from blast-containing mononuclear cells (MNC) in AML/MDS cases with a DC viability of more than 60%. In all, 39% to 64% of these DC were mature; 31% to 52% of leukemic blasts could be converted to DCleu and DCleu-proportions in the suspension were 2% to 70% (13%). Average results of all culture methods tested were comparable, however not every given case of AML could be differentiated to DC with 1 selected method. However performing a pre-analysis with 3 DC-generating methods (MCM-Mimic, Picibanil, Ca-ionophore) we could generate DC in any given case. Functional analyses provided proof, that DC primed T cells to antileukemia-directed cytotoxic cells, although an anti-leukemic reaction was not achieved in every case. In summary our data show that a successful, quantitative DC/DCleu generation is possible with the best of 3 previously tested methods in any given case. Reasons for different functional behaviors of DC-primed T cells must be evaluated to design a practicable DC-based vaccination strategy.

TRIM32 promotes retinoic acid receptor α-mediated differentiation in human promyelogenous leukemic cell line HL60

International Nuclear Information System (INIS)

Sato, Tomonobu; Okumura, Fumihiko; Iguchi, Akihiro; Ariga, Tadashi; Hatakeyama, Shigetsugu

2012-01-01

Highlights: ► TRIM32 enhanced RARα-mediated transcriptional activity even in the absence of RA. ► TRIM32 stabilized RARα in the human promyelogenous leukemic cell line HL60. ► Overexpression of TRIM32 in HL60 cells induced granulocytic differentiation. ► TRIM32 may function as a coactivator for RARα-mediated transcription in APL cells. -- Abstract: Ubiquitination, one of the posttranslational modifications, appears to be involved in the transcriptional activity of nuclear receptors including retinoic acid receptor α (RARα). We previously reported that an E3 ubiquitin ligase, TRIM32, interacts with several important proteins including RARα and enhances transcriptional activity of RARα in mouse neuroblastoma cells and embryonal carcinoma cells. Retinoic acid (RA), which acts as a ligand to nuclear receptors including RARα, plays crucial roles in development, differentiation, cell cycles and apoptosis. In this study, we found that TRIM32 enhances RARα-mediated transcriptional activity even in the absence of RA and stabilizes RARα in the human promyelogenous leukemic cell line HL60. Moreover, we found that overexpression of TRIM32 in HL60 cells suppresses cellular proliferation and induces granulocytic differentiation even in the absence of RA. These findings suggest that TRIM32 functions as one of the coactivators for RARα-mediated transcription in acute promyelogenous leukemia (APL) cells, and thus TRIM32 may become a potentially therapeutic target for APL.

Cyanobacteria as a Source for Novel Anti-Leukemic Compounds.

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Humisto, Anu; Herfindal, Lars; Jokela, Jouni; Karkman, Antti; Bjørnstad, Ronja; Choudhury, Romi R; Sivonen, Kaarina

2016-01-01

Cyanobacteria are an inspiring source of bioactive secondary metabolites. These bioactive agents are a diverse group of compounds which are varying in their bioactive targets, the mechanisms of action, and chemical structures. Cyanobacteria from various environments, especially marine benthic cyanobacteria, are found to be rich sources for the search for novel bioactive compounds. Several compounds with anticancer activities have been discovered from cyanobacteria and some of these have succeeded to enter the clinical trials. Varying anticancer agents are needed to overcome increasing challenges in cancer treatments. Different search methods are used to reveal anticancer compounds from natural products, but cell based methods are the most common. Cyanobacterial bioactive compounds as agents against acute myeloid leukemia are not well studied. Here we examined our new results combined with previous studies of anti-leukemic compounds from cyanobacteria with emphasis to reveal common features in strains producing such activity. We report that cyanobacteria harbor specific anti-leukemic compounds since several studied strains induced apoptosis against AML cells but were inactive against non-malignant cells like hepatocytes. We noted that particularly benthic strains from the Baltic Sea, such as Anabaena sp., were especially potential AML apoptosis inducers. Taken together, this review and re-analysis of data demonstrates the power of maintaining large culture collections for the search for novel bioactivities, and also how anti-AML activity in cyanobacteria can be revealed by relatively simple and low-cost assays.

Long Terminal Repeat CRISPR-CAR-Coupled "Universal" T Cells Mediate Potent Anti-leukemic Effects.

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Georgiadis, Christos; Preece, Roland; Nickolay, Lauren; Etuk, Aniekan; Petrova, Anastasia; Ladon, Dariusz; Danyi, Alexandra; Humphryes-Kirilov, Neil; Ajetunmobi, Ayokunmi; Kim, Daesik; Kim, Jin-Soo; Qasim, Waseem

2018-03-06

Gene editing can be used to overcome allo-recognition, which otherwise limits allogeneic T cell therapies. Initial proof-of-concept applications have included generation of such "universal" T cells expressing chimeric antigen receptors (CARs) against CD19 target antigens combined with transient expression of DNA-targeting nucleases to disrupt the T cell receptor alpha constant chain (TRAC). Although relatively efficient, transgene expression and editing effects were unlinked, yields variable, and resulting T cell populations heterogeneous, complicating dosing strategies. We describe a self-inactivating lentiviral "terminal" vector platform coupling CAR expression with CRISPR/Cas9 effects through incorporation of an sgRNA element into the ΔU3 3' long terminal repeat (LTR). Following reverse transcription and duplication of the hybrid ΔU3-sgRNA, delivery of Cas9 mRNA resulted in targeted TRAC locus cleavage and allowed the enrichment of highly homogeneous (>96%) CAR + (>99%) TCR - populations by automated magnetic separation. Molecular analyses, including NGS, WGS, and Digenome-seq, verified on-target specificity with no evidence of predicted off-target events. Robust anti-leukemic effects were demonstrated in humanized immunodeficient mice and were sustained longer than by conventional CAR + TCR + T cells. Terminal-TRAC (TT) CAR T cells offer the possibility of a pre-manufactured, non-HLA-matched CAR cell therapy and will be evaluated in phase 1 trials against B cell malignancies shortly. Copyright © 2018 The American Society of Gene and Cell Therapy. Published by Elsevier Inc. All rights reserved.

Differentiation-inducing effects of small fruit juices on HL-60 leukemic cells.

Science.gov (United States)

Yoshizawa, Y; Kawaii, S; Urashima, M; Fukase, T; Sato, T; Murofushi, N; Nishimura, H

2000-08-01

Epidemiological studies indicate that high intakes of fruits and vegetables are associated with a reduced risk of cancer, and several plant-derived drugs have been developed in medical oncology. Since only a small part of the flora has been tested for any kind of bioactivity, we chose small fruits as sources of differentiation-inducing activity against HL-60 leukemic cells. We have prepared juices from various small fruits that grow mainly in the northern part of Japan. Screening of 43 samples indicated that juices of Actinidia polygama Maxim., Rosa rugosa Thunb., Vaccinium smallii A. Gray, and Sorbus sambucifolia Roem. strongly induced differentiation of HL-60 cells to monocyte/macrophage characteristics in a concentration-dependent manner as indicated by histochemical and biochemical examinations.

Activation of the complement cascade enhances motility of leukemic cells by downregulating expression of HO-1.

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Abdelbaset-Ismail, A; Borkowska-Rzeszotek, S; Kubis, E; Bujko, K; Brzeźniakiewicz-Janus, K; Bolkun, L; Kloczko, J; Moniuszko, M; Basak, G W; Wiktor-Jedrzejczak, W; Ratajczak, M Z

2017-02-01

As a crucial arm of innate immunity, the complement cascade (ComC) is involved both in mobilization of normal hematopoietic stem/progenitor cells (HSPCs) from bone marrow (BM) into peripheral blood and in their homing to BM. Despite the fact that ComC cleavage fragments alone do not chemoattract normal HSPCs, we found that leukemia cell lines as well as clonogenic blasts from chronic myeloid leukemia and acute myeloid leukemia patients respond robustly to C3 and C5 cleavage fragments by chemotaxis and increased adhesion. This finding was supported by the detection of C3a and C5a receptors in cells from human malignant hematopoietic cell lines and patient blasts at the mRNA (reverse transcriptase-polymerase chain reaction) and protein level (fluorescence-activated cell sorting), and by the demonstration that these receptors respond to stimulation by C3a and C5a by phosphorylation of p42/44 and p38 mitogen-activated protein kinases (MAPK), and protein kinase B (PKB/AKT). We also found that inducible heme oxygenase 1 (HO-1) is a negative regulator of ComC-mediated trafficking of leukemic cells, and that stimulation of leukemic cells by C3 or C5 cleavage fragments activates p38 MAPK, which downregulates HO-1 expression, rendering cells more mobile. We conclude that activation of the ComC in leukemia/lymphoma patients (for example, as a result of accompanying infections) enhances the motility of malignant cells and contributes to their spread in a p38 MAPK-HO-1-dependent manner. Therefore, inhibition of p38 MAPK or upregulation of HO-1 by small-molecule modulators would have a beneficial effect on ameliorating cell migration-mediated expansion of leukemia/lymphoma cells when the ComC becomes activated.

Activation of the complement cascade enhances motility of leukemic cells by downregulating expression of HO-1

Science.gov (United States)

Abdelbaset-Ismail, A; Borkowska-Rzeszotek, S; Kubis, E; Bujko, K; Brzeźniakiewicz-Janus, K; Bolkun, L; Kloczko, J; Moniuszko, M; Basak, G W; Wiktor-Jedrzejczak, W; Ratajczak, M Z

2017-01-01

As a crucial arm of innate immunity, the complement cascade (ComC) is involved both in mobilization of normal hematopoietic stem/progenitor cells (HSPCs) from bone marrow (BM) into peripheral blood and in their homing to BM. Despite the fact that ComC cleavage fragments alone do not chemoattract normal HSPCs, we found that leukemia cell lines as well as clonogenic blasts from chronic myeloid leukemia and acute myeloid leukemia patients respond robustly to C3 and C5 cleavage fragments by chemotaxis and increased adhesion. This finding was supported by the detection of C3a and C5a receptors in cells from human malignant hematopoietic cell lines and patient blasts at the mRNA (reverse transcriptase-polymerase chain reaction) and protein level (fluorescence-activated cell sorting), and by the demonstration that these receptors respond to stimulation by C3a and C5a by phosphorylation of p42/44 and p38 mitogen-activated protein kinases (MAPK), and protein kinase B (PKB/AKT). We also found that inducible heme oxygenase 1 (HO-1) is a negative regulator of ComC-mediated trafficking of leukemic cells, and that stimulation of leukemic cells by C3 or C5 cleavage fragments activates p38 MAPK, which downregulates HO-1 expression, rendering cells more mobile. We conclude that activation of the ComC in leukemia/lymphoma patients (for example, as a result of accompanying infections) enhances the motility of malignant cells and contributes to their spread in a p38 MAPK–HO-1-dependent manner. Therefore, inhibition of p38 MAPK or upregulation of HO-1 by small-molecule modulators would have a beneficial effect on ameliorating cell migration-mediated expansion of leukemia/lymphoma cells when the ComC becomes activated. PMID:27451975

Differential Effects of Tea Extracts on Growth and Cytokine Production by Normal and Leukemic Human Leukocytes

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Diana Bayer

2012-04-01

Full Text Available Background: Tea is one of the world’s most highly consumed beverages, second only to water. It is affordable and abundant and thus has great potential for improving health of those in both developed and developing areas. Green, oolong, and black teas differ in the extent of fermentation and types of bioactive polyphenols produced. Green tea and its major polyphenol decrease growth of some cancer cells and effect production of immune system cytokines. This study compares the effects of different types of tea extracts on viability and cytokine production by normal and leukemic human T lymphocytes. Generation of the toxic reactive oxygen species H2O2 by extracts was also examined.Methods: The Jurkat T lymphoblastic leukemia cells and mitogen-stimulated normal human peripheral blood mononuclear cells were used in this study. Cell viability was determined by (3-4,5-dimethylthiamizol-2-yl-diphenyltetrazolium bromide assay and production of interleukin-2 by Enzyme-Linked ImmunoSorbent Assay. Levels of H2O2 generated by tea extracts were determined using the xylenol-orange method.Results: We found that green, oolong, and black tea extracts differentially effect the growth and viability of T lymphoblastic leukemia cells and normal peripheral blood mononuclear cells, substantially decreasing both growth and viability of leukemic T lymphocytes and having much lesser effects on their normal counterparts. Tea extracts also had differential effects on the production of the T lymphocyte growth factor interleukin-2, significantly decreasing production by leukemic cells while having only minor effects on normal cells. All three extracts induced H2O2 generation, with green and oolong tea extracts having the greatest effect. Leukemic cells were much more susceptible to growth inhibition and killing by H2O2 than normal lymphocytes.Functional Foods in Health and Disease 2012, 2(4:72-85 Conclusions: The three tea extracts studied altered leukemic T lymphocyte

Quantitative assay for the number of leukemic spleen colony forming unit in radiation-induced murine myeloid leukemia

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Nara, N [Tokyo Medical and Dental Univ. (Japan). School of Medicine; Bessho, M

1981-11-01

In mice with myelogenous leukemia, leukemic spleen colony forming units were assayed quantitatively. When 5 x 10/sup 3/ - 2 x 10/sup 4/ leukemic cells were transplanted to other mice of the same strain, a rectilinear relationship (p < 0.01) was found between the number of the cells transplanted and that of the colonies formed on the surface of the spleen. From these results, the authors considered that myelogenous leukemia in mice is an adequate model for acute myelogenous leukemia in human adults, and that the quantitative assay of the leukemic colony forming units can be used for sensitivity tests of antileukemic agents.

Fludarabine-mediated circumvention of cytarabine resistance is associated with fludarabine triphosphate accumulation in cytarabine-resistant leukemic cells.

Science.gov (United States)

Yamamoto, Shuji; Yamauchi, Takahiro; Kawai, Yasukazu; Takemura, Haruyuki; Kishi, Shinji; Yoshida, Akira; Urasaki, Yoshimasa; Iwasaki, Hiromichi; Ueda, Takanori

2007-02-01

The combination of cytarabine (ara-C) with fludarabine is a common approach to treating resistant acute myeloid leukemia. Success depends on a fludarabine triphosphate (F-ara-ATP)-mediated increase in the active intracellular metabolite of ara-C, ara-C 5'-triphosphate (ara-CTP). Therapy-resistant leukemia may exhibit ara-C resistance, the mechanisms of which might induce cross-resistance to fludarabine with reduced F-ara-ATP formation. The present study evaluated the effect of combining ara-C and fludarabine on ara-C-resistant leukemic cells in vitro. Two variant cell lines (R1 and R2) were 8-fold and 10-fold more ara-C resistant, respectively, than the parental HL-60 cells. Reduced deoxycytidine kinase activity was demonstrated in R1 and R2 cells, and R2 cells also showed an increase in cytosolic 5'-nucleotidase II activity. Compared with HL-60 cells, R1 and R2 cells produced smaller amounts of ara-CTP. Both variants accumulated less F-ara-ATP than HL-60 cells and showed cross-resistance to fludarabine nucleoside (F-ara-A). R2 cells, however, accumulated much smaller amounts of F-ara-ATP and were more F-ara-A resistant than R1 cells. In HL-60 and R1 cells, F-ara-A pretreatment followed by ara-C incubation produced F-ara-ATP concentrations sufficient for augmenting ara-CTP production, thereby enhancing ara-C cytotoxicity. No potentiation was observed in R2 cells. Nucleotidase might preferentially degrade F-ara-A monophosphate over ara-C monophosphate, leading to reduced F-ara-ATP production and thereby compromising the F-ara-A-mediated potentiation of ara-C cytotoxicity in R2 cells. Thus, F-ara-A-mediated enhancement of ara-C cytotoxicity depended on F-ara-ATP accumulation in ara-C-resistant leukemic cells but ultimately was associated with the mechanism of ara-C resistance.

Cannabidiol Reduces Leukemic Cell Size - But Is It Important?

Science.gov (United States)

Kalenderoglou, Nikoletta; Macpherson, Tara; Wright, Karen L

2017-01-01

The anti-cancer effect of the plant-derived cannabinoid, cannabidiol, has been widely demonstrated both in vivo and in vitro . However, this body of preclinical work has not been translated into clinical use. Key issues around this failure can be related to narrow dose effects, the cell model used and incomplete efficacy. A model of acute lymphoblastic disease, the Jurkat T cell line, has been used extensively to study the cannabinoid system in the immune system and cannabinoid-induced apoptosis. Using these cells, this study sought to investigate the outcome of those remaining viable cells post-treatment with cannabidiol, both in terms of cell size and tracking any subsequent recovery. The phosphorylation status of the mammalian Target of Rapamycin (mTOR) signaling pathway and the downstream target ribosomal protein S6, were measured. The ability of cannabidiol to exert its effect on cell viability was also evaluated in physiological oxygen conditions. Cannabidiol reduced cell viability incompletely, and slowed the cell cycle with fewer cells in the G2/M phase of the cell cycle. Cannabidiol reduced phosphorylation of mTOR, PKB and S6 pathways related to survival and cell size. The remaining population of viable cells that were cultured in nutrient rich conditions post-treatment were able to proliferate, but did not recover to control cell numbers. However, the proportion of viable cells that were gated as small, increased in response to cannabidiol and normally sized cells decreased. This proportion of small cells persisted in the recovery period and did not return to basal levels. Finally, cells grown in 12% oxygen (physiological normoxia) were more resistant to cannabidiol. In conclusion, these results indicate that cannabidiol causes a reduction in cell size, which persists post-treatment. However, resistance to cannabidiol under physiological normoxia for these cells would imply that cannabidiol may not be useful in the clinic as an anti-leukemic agent.

Detection of a novel specificity (CTLA-4) in ATG/TMG globulins and sera from ATG-treated leukemic patients.

Science.gov (United States)

Pistillo, Maria Pia; Tazzari, Pier Luigi; Bonifazi, Francesca; Bandini, Giuseppe; Kato, Tomohiro; Matsui, Toshihiro; Nishioka, Kusuki; Conte, Roberto; Ferrara, Giovanni Battista

2002-04-27

T-cell costimulation has been shown to provide positive signals for T-cell activation and generation of effector activity. In this study, we analyzed the presence of antibodies (Abs) against the T-lymphocyte costimulatory molecules CD28, CTLA-4, CD80, and CD86 in anti-T-lymphocyte (ATG) and antithymocyte (TMG) globulin preparations to address their mechanism of action. We focused our attention on the role of CTLA-4-specific Abs in the immunosuppressive effect of ATG/TMG, because anti-CTLA-4 agonistic Abs may suppress T-cell proliferation and nonagonistic Abs may lead to T-cell depletion through an Ab-dependent cell cytotoxicity mechanism. ATG/TMG and patients' sera were tested for binding to recombinant human costimulatory molecules by ELISA techniques. CTLA-4 specificity was also analyzed by cytoplasmic immunofluorescence staining of a CTLA-4 transfectant by competitive inhibition immunofluorescence and by cell proliferation assay in allogeneic mixed lymphocyte reaction (MLR). Either ATG or TMG predominantly contained anti-CTLA-4 Abs, with higher reactivity in ATG followed by anti-CD86 and -CD28 Abs, whereas anti-CD80 Abs were found only in ATG. Anti-CTLA-4 Abs present in ATG/TMG recognized the native form of CTLA-4 molecule, and their removal reduced the effect of ATG in an allogeneic MLR. Kinetic studies indicated that such Abs were present in the sera of 12 ATG-treated leukemic patients up to 21 days after ATG administration. These data suggest that the novel anti-CTLA-4 Abs found in ATG may greatly contribute to its immunosuppressive effect, thus accounting for the absence of rejection and exceptionally low incidence of graft-versus-host disease in the group of patients analyzed.

Human surfactant protein D alters oxidative stress and HMGA1 expression to induce p53 apoptotic pathway in eosinophil leukemic cell line.

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Lakshna Mahajan

Full Text Available Surfactant protein D (SP-D, an innate immune molecule, has an indispensable role in host defense and regulation of inflammation. Immune related functions regulated by SP-D include agglutination of pathogens, phagocytosis, oxidative burst, antigen presentation, T lymphocyte proliferation, cytokine secretion, induction of apoptosis and clearance of apoptotic cells. The present study unravels a novel ability of SP-D to reduce the viability of leukemic cells (eosinophilic leukemic cell line, AML14.3D10; acute myeloid leukemia cell line, THP-1; acute lymphoid leukemia cell lines, Jurkat, Raji; and human breast epithelial cell line, MCF-7, and explains the underlying mechanisms. SP-D and a recombinant fragment of human SP-D (rhSP-D induced G2/M phase cell cycle arrest, and dose and time-dependent apoptosis in the AML14.3D10 eosinophilic leukemia cell line. Levels of various apoptotic markers viz. activated p53, cleaved caspase-9 and PARP, along with G2/M checkpoints (p21 and Tyr15 phosphorylation of cdc2 showed significant increase in these cells. We further attempted to elucidate the underlying mechanisms of rhSP-D induced apoptosis using proteomic analysis. This approach identified large scale molecular changes initiated by SP-D in a human cell for the first time. Among others, the proteomics analysis highlighted a decreased expression of survival related proteins such as HMGA1, overexpression of proteins to protect the cells from oxidative burst, while a drastic decrease in mitochondrial antioxidant defense system. rhSP-D mediated enhanced oxidative burst in AML14.3D10 cells was confirmed, while antioxidant, N-acetyl-L-cysteine, abrogated the rhSP-D induced apoptosis. The rhSP-D mediated reduced viability was specific to the cancer cell lines and viability of human PBMCs from healthy controls was not affected. The study suggests involvement of SP-D in host's immunosurveillance and therapeutic potential of rhSP-D in the eosinophilic leukemia and

Transferrin-polycation-mediated introduction of DNA into human leukemic cells: Stimulation by agents that affect the survival of transfected DNA or modulate transferrin receptor levels

International Nuclear Information System (INIS)

Cotten, M.; Laengle-Rouault, F.; Kirlappos, H.; Wagner, E.; Mechtler, K.; Zenke, M.; Beug, H.; Birnstiel, M.L.

1990-01-01

The authors have subverted a receptor-mediated endocytosis event to transport genes into human leukemic cells. By coupling the natural iron-delivery protein transferrin to the DNA-binding polycations polylysine or protamine, they have created protein conjugates that bind nucleic acids and carry them into the cell during the normal transferrin cycle. They demonstrate here that this procedure is useful for a human leukemic cell line. They enhanced the rate of gene delivery by (i) increasing the transferrin receptor density through treatment of the cells with the cell permeable iron chelator desferrioxamine, (ii) interfering with the synthesis of heme with succinyl acetone treatment, or (iii) stimulating the degradation of heme with cobalt chloride treatment. Consistent with gene delivery as an endocytosis event, they show that the subsequent expression in K-562 cells of a gene included in the transported DNA depends upon the cellular presence of the lysosomotropic agent chloroquine. By contrast, monensin blocks transferrinfection, as does incubation of the cells at 18 degree C

An antigen shared by human granulocytes, monocytes, marrow granulocyte precursors and leukemic blasts.

Science.gov (United States)

Shumak, K H; Rachkewich, R A

1983-01-01

An antibody to human granulocytes was raised in rabbits by immunization with granulocytes pretreated with rabbit antibody to contaminating antigens. The antibody reacted not only with granulocytes but also with monocytes and bone marrow granulocyte precursors including colony-forming units in culture (CFU-C). In tests with leukemic cells, the antibody reacted with blasts from most (8 of 9) patients with acute myelomonoblastic leukemia and from some patients with acute myeloblastic leukemia, morphologically undifferentiated acute leukemia and chronic myelogenous leukemia in blast crisis. The antibody did not react with blasts from patients with acute lymphoblastic leukemia nor with leukemic cells from patients with chronic lymphocytic leukemia.

Elimination of acute muelogenous leukemic cells from marrow and tumor suspensions in the rat with 4-hydroperoxycyclophosphamide

International Nuclear Information System (INIS)

Sharkis, S.J.; Santos, G.W.; Colvin, M.

1980-01-01

Cell suspensions of normal rat marrow mixed with rat acute myelogenous leukemic cells were prepared and incubated in vitro with graded doses of 4-hydroperoxycyclophosphamide (4HC). The cell suspensions were injected into rats prepared with a lethal dose of total body irradiation. Animals injected with these cells survived fatal irradiation induced aplasia. In a dose related manner 4HC was able to purge tumor cells from the cell mixtures. Thus, animals given cell suspensions incubated with the lower doses of 4HC showed prolonged survived before death from leukemia and animals given cell suspensions incubated with higher doses of 4HC survival lethal irradiation without the subsequent appearance of leukemia. These studies clearly establish that tumor cells may be eliminated from normal marrow suspensions without completely destroying the pluripotent stem cells

The Leukemic Stem Cell Niche: Adaptation to “Hypoxia” versus Oncogene Addiction

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Giulia Cheloni

2017-01-01

Full Text Available Previous studies based on low oxygen concentrations in the incubation atmosphere revealed that metabolic factors govern the maintenance of normal hematopoietic or leukemic stem cells (HSC and LSC. The physiological oxygen concentration in tissues ranges between 0.1 and 5.0%. Stem cell niches (SCN are placed in tissue areas at the lower end of this range (“hypoxic” SCN, to which stem cells are metabolically adapted and where they are selectively hosted. The data reported here indicated that driver oncogenic proteins of several leukemias are suppressed following cell incubation at oxygen concentration compatible with SCN physiology. This suppression is likely to represent a key positive regulator of LSC survival and maintenance (self-renewal within the SCN. On the other hand, LSC committed to differentiation, unable to stand suppression because of addiction to oncogenic signalling, would be unfit to home in SCN. The loss of oncogene addiction in SCN-adapted LSC has a consequence of crucial practical relevance: the refractoriness to inhibitors of the biological activity of oncogenic protein due to the lack of their molecular target. Thus, LSC hosted in SCN are suited to sustain the long-term maintenance of therapy-resistant minimal residual disease.

Isolation of a novel chronic lymphocytic leukemic (CLL) cell line and development of an in vivo mouse model of CLL.

Science.gov (United States)

Kellner, Joshua; Wierda, William; Shpall, Elizabeth; Keating, Michael; McNiece, Ian

2016-01-01

Leukemic cell lines have become important tools for studies of disease providing a monoclonal cell population that can be extensively expanded in vitro while preserving leukemic cellular characteristics. However, studies of chronic lymphocytic leukemia (CLL) have been impeded in part by the lack of continuous human cell lines. CLL cells have a high spontaneous apoptosis rate in vitro and exhibit minimal proliferation in xenograft models. Therefore, there is a need for development of primary CLL cell lines and we describe the isolation of such a line from the bone marrow of a CLL patient (17p deletion and TP53 mutation) which has been in long term culture for more than 12 months with continuous proliferation. The CLL cell line (termed MDA-BM5) which was generated in vitro with continuous co-culture on autologous stromal cells is CD19+CD5+ and shows an identical pattern of somatic hypermutation as determined in the patient's bone marrow (BM), confirming the origin of the cells from the original CLL clone. MDA-BM5 cells were readily transplantable in NOD/SCID gamma null mice (NSG) with disease developing in the BM, liver and spleen. BM cells from quaternary serial transplantation in NSG mice demonstrated the presence of CD19+CD5+ cells with Ig restricted to lambda which is consistent with the original patient cells. These studies describe a new CLL cell line from a patient with del(17p) that provides a unique model for in vitro and in vivo studies. Copyright © 2015 Elsevier Ltd. All rights reserved.

Cannabidiol Reduces Leukemic Cell Size – But Is It Important?

Science.gov (United States)

Kalenderoglou, Nikoletta; Macpherson, Tara; Wright, Karen L.

2017-01-01

The anti-cancer effect of the plant-derived cannabinoid, cannabidiol, has been widely demonstrated both in vivo and in vitro. However, this body of preclinical work has not been translated into clinical use. Key issues around this failure can be related to narrow dose effects, the cell model used and incomplete efficacy. A model of acute lymphoblastic disease, the Jurkat T cell line, has been used extensively to study the cannabinoid system in the immune system and cannabinoid-induced apoptosis. Using these cells, this study sought to investigate the outcome of those remaining viable cells post-treatment with cannabidiol, both in terms of cell size and tracking any subsequent recovery. The phosphorylation status of the mammalian Target of Rapamycin (mTOR) signaling pathway and the downstream target ribosomal protein S6, were measured. The ability of cannabidiol to exert its effect on cell viability was also evaluated in physiological oxygen conditions. Cannabidiol reduced cell viability incompletely, and slowed the cell cycle with fewer cells in the G2/M phase of the cell cycle. Cannabidiol reduced phosphorylation of mTOR, PKB and S6 pathways related to survival and cell size. The remaining population of viable cells that were cultured in nutrient rich conditions post-treatment were able to proliferate, but did not recover to control cell numbers. However, the proportion of viable cells that were gated as small, increased in response to cannabidiol and normally sized cells decreased. This proportion of small cells persisted in the recovery period and did not return to basal levels. Finally, cells grown in 12% oxygen (physiological normoxia) were more resistant to cannabidiol. In conclusion, these results indicate that cannabidiol causes a reduction in cell size, which persists post-treatment. However, resistance to cannabidiol under physiological normoxia for these cells would imply that cannabidiol may not be useful in the clinic as an anti-leukemic agent. PMID

Chronic Myelogenous Leukemia Cells Contribute to the Stromal Myofibroblasts in Leukemic NOD/SCID Mouse In Vivo

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Ryosuke Shirasaki

2012-01-01

Full Text Available We recently reported that chronic myelogenous leukemia (CML cells converted into myofibroblasts to create a microenvironment for proliferation of CML cells in vitro. To analyze a biological contribution of CML-derived myofibroblasts in vivo, we observed the characters of leukemic nonobese diabetes/severe combined immunodeficiency (NOD/SCID mouse. Bone marrow nonadherent mononuclear cells as well as human CD45-positive cells obtained from CML patients were injected to the irradiated NOD/SCID mice. When the chimeric BCR-ABL transcript was demonstrated in blood, human CML cells were detected in NOD/SCID murine bone marrow. And CML-derived myofibroblasts composed with the bone marrow-stroma, which produced significant amounts of human vascular endothelial growth factor A. When the parental CML cells were cultured with myofibroblasts separated from CML cell-engrafted NOD/SCID murine bone marrow, CML cells proliferated significantly. These observations indicate that CML cells make an adequate microenvironment for their own proliferation in vivo.

Effect of cAMP signaling on expression of glucocorticoid receptor, Bim and Bad in glucocorticoid-sensitive and resistant leukemic and multiple myeloma cells.

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Dong, Hongli; Carlton, Michael E; Lerner, Adam; Epstein, Paul M

2015-01-01

Stimulation of cAMP signaling induces apoptosis in glucocorticoid-sensitive and resistant CEM leukemic and MM.1 multiple myeloma cell lines, and this effect is enhanced by dexamethasone in both glucocorticoid-sensitive cell types and in glucocorticoid-resistant CEM cells. Expression of the mRNA for the glucocorticoid receptor alpha (GR) promoters 1A3, 1B and 1C, expression of mRNA and protein for GR, and the BH3-only proapoptotic proteins, Bim and Bad, and the phosphorylation state of Bad were examined following stimulation of the cAMP and glucocorticoid signaling pathways. Expression levels of GR promoters were increased by cAMP and glucocorticoid signaling, but GR protein expression was little changed in CEM and decreased in MM.1 cells. Stimulation of these two signaling pathways induced Bim in CEM cells, induced Bad in MM.1 cells, and activated Bad, as indicated by its dephosphorylation on ser112, in both cell types. This study shows that leukemic and multiple myeloma cells, including those resistant to glucocorticoids, can be induced to undergo apoptosis by stimulating the cAMP signaling pathway, with enhancement by glucocorticoids, and the mechanism by which this occurs may be related to changes in Bim and Bad expression, and in all cases, to activation of Bad.

Disrupting BCR-ABL in combination with secondary leukemia-specific pathways in CML cells leads to enhanced apoptosis and decreased proliferation.

Science.gov (United States)

Woessner, David W; Lim, Carol S

2013-01-07

Chronic myeloid leukemia (CML) is a myeloproliferative disorder caused by expression of the fusion gene BCR-ABL following a chromosomal translocation in the hematopoietic stem cell. Therapeutic management of CML uses tyrosine kinase inhibitors (TKIs), which block ABL-signaling and effectively kill peripheral cells with BCR-ABL. However, TKIs are not curative, and chronic use is required in order to treat CML. The primary failure for TKIs is through the development of a resistant population due to mutations in the TKI binding regions. This led us to develop the mutant coiled-coil, CC(mut2), an alternative method for BCR-ABL signaling inhibition by targeting the N-terminal oligomerization domain of BCR, necessary for ABL activation. In this article, we explore additional pathways that are important for leukemic stem cell survival in K562 cells. Using a candidate-based approach, we test the combination of CC(mut2) and inhibitors of unique secondary pathways in leukemic cells. Transformative potential was reduced following silencing of the leukemic stem cell factor Alox5 by RNA interference. Furthermore, blockade of the oncogenic protein MUC-1 by the novel peptide GO-201 yielded reductions in proliferation and increased cell death. Finally, we found that inhibiting macroautophagy using chloroquine in addition to blocking BCR-ABL signaling with the CC(mut2) was most effective in limiting cell survival and proliferation. This study has elucidated possible combination therapies for CML using novel blockade of BCR-ABL and secondary leukemia-specific pathways.

In vitro proliferation of normal and leukemic human leukocytes controlled by an inhibitory endopeptide. [/sup 3/H-TdR incorporation

Energy Technology Data Exchange (ETDEWEB)

Balazs, A; Mann, J; Takacsi-Nagy, L; Zimonyi, I; Molnar, A; Klupp, T [Inst. of Experimental Medicine, Budapest (Hungary); Istvan Municipal Hospital, Budapest (Hungary); Heim Pal Children' s Hospital Budapest, (Hungary))

1983-01-01

GI-3, an endogenous inhibitory fraction isolated from leukocytes, selectively inhibits the proliferation of granuloid precursor cells in a non-toxic manner. Its active principle is an acidic chlor-tolidine positive decapeptide. The in vitro effect on normal and acute leukemic human bone marrow and blood cells was examined. A dose dependent inhibition by GI-3 of /sup 3/H-TdR incorporation into myeloid cells of normal bone marrow was found, the sensitivity of human cells being higher than that of rat cells. The proliferation of the target leukemic bone marrow and blood cells was also decreased by the endogenous inhibitor in a dose-dependent manner in untreated subjects as well as in patients in remission or relapse. The rate of inhibition of leukemic cell proliferation in the short-term suspension system examined almost coincided with the action of well-known cytostatics applied for comparison. Beyond its direct cytostatic effect, GI-3 could be used in the differential diagnosis of blastic leukemias, complementing the routine cytochemical methods.

Analysis of CTCL cell lines reveals important differences between mycosis fungoides/Sézary syndrome vs. HTLV-1+ leukemic cell lines

DEFF Research Database (Denmark)

Netchiporouk, Elena; Gantchev, Jennifer; Tsang, Matthew

2017-01-01

HTLV-1 is estimated to affect ~20 million people worldwide and in ~5% of carriers it produces Adult T-Cell Leukemia/Lymphoma (ATLL), which can often masquerade and present with classic erythematous pruritic patches and plaques that are typically seen in Mycosis Fungoides (MF) and Sézary Syndrome...... (SS), the most recognized variants of Cutaneous T-Cell Lymphomas (CTCL). For many years the role of HTLV- 1 in the pathogenesis of MF/SS has been hotly debated. In this study we analyzed CTCL vs. HTLV-1+ leukemic cells. We performed G-banding/spectral karyotyping, extensive gene expression analysis......, TP53 sequencing in the 11 patient-derived HTLV- 1+ (MJ and Hut102) vs. HTLV-1- (Myla, Mac2a, PB2B, HH, H9, Hut78, SZ4, Sez4 and SeAx) CTCL cell lines. We further tested drug sensitivities to commonly used CTCL therapies and studied the ability of these cells to produce subcutaneous xenograft tumors...

T cell clones which share T cell receptor epitopes differ in phenotype, function and specificity

NARCIS (Netherlands)

Yssel, H.; Blanchard, D.; Boylston, A.; de Vries, J. E.; Spits, H.

1986-01-01

Recently, we described a monoclonal antibody (3D6) that reacts with the T cell receptor (Ti) of the T leukemic cell line HPB-ALL and that cross-reacts with 2-10% of the T cells of normal healthy individuals. In this study we report the establishment of T cell clones that are 3D6+ but that differ in

Lack of correlation between immunologic markers and cell surface ultrastructure in the leukemic phase of lymphoproliferative diseases

Energy Technology Data Exchange (ETDEWEB)

Golomb, Harvey M.; Simon, Deberah

1977-01-01

In a prospective study of malignant cells from 13 patients with the leukemic phase of lymphoproliferative diseases, we wished to determine whether any correlation between the immunologic markers and the cell surface ultrastructure. Five patients had chronic lymphocytic leukemia, four had malignant lymphomas, poorly differentiated lymphocytic type, two had the Sezary syndrome, and one each had acute prolymphocytic leukemia and acute lymphocytic leukemia. Cell separation and isolation was done at room temperature for all specimens. Immunologic markers tested for were surface immunoglobins, a B-cell property, and E-rosettes, a T-cell property. Three patients had T-cell diseases, 6 had B-cell diseases, and 4 were classified as ''null.'' All but one patient had moderate to large numbers of microvilli on their malignant cells. The single exception had a typical B-cell form of chronic lymphocytic leukemia. There appears to be no correlation between immunologic markers and cell surface ultrastructure; therefore, SEM appears not to be valuable in the diagnosis or classification of immunologic sub-types of certain lymphoproliferative diseases.

Transcriptional activation of prostate specific homeobox gene NKX3-1 in subsets of T-cell lymphoblastic leukemia (T-ALL.

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Stefan Nagel

Full Text Available Homeobox genes encode transcription factors impacting key developmental processes including embryogenesis, organogenesis, and cell differentiation. Reflecting their tight transcriptional control, homeobox genes are often embedded in large non-coding, cis-regulatory regions, containing tissue specific elements. In T-cell acute lymphoblastic leukemia (T-ALL homeobox genes are frequently deregulated by chromosomal aberrations, notably translocations adding T-cell specific activatory elements. NKX3-1 is a prostate specific homeobox gene activated in T-ALL patients expressing oncogenic TAL1 or displaying immature T-cell characteristics. After investigating regulation of NKX3-1 in primary cells and cell lines, we report its ectopic expression in T-ALL cells independent of chromosomal rearrangements. Using siRNAs and expression profiling, we exploited NKX3-1 positive T-ALL cell lines as tools to investigate aberrant activatory mechanisms. Our data confirmed NKX3-1 activation by TAL1/GATA3/LMO and identified LYL1 as an alternative activator in immature T-ALL cells devoid of GATA3. Moreover, we showed that NKX3-1 is directly activated by early T-cell homeodomain factor MSX2. These activators were regulated by MLL and/or by IL7-, BMP4- and IGF2-signalling. Finally, we demonstrated homeobox gene SIX6 as a direct leukemic target of NKX3-1 in T-ALL. In conclusion, we identified three major mechanisms of NKX3-1 regulation in T-ALL cell lines which are represented by activators TAL1, LYL1 and MSX2, corresponding to particular T-ALL subtypes described in patients. These results may contribute to the understanding of leukemic transcriptional networks underlying disturbed T-cell differentiation in T-ALL.

Radiobiological heterogeneity of leukemic lymphocyte precursors from acute lymphoblastic leukemia patients

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Uckun, F.M.; Kim, T.H.; Ramsay, N.C.; Min, W.S.; Song, C.W.

1989-01-01

The report outlines the authors' findings on the radiobiological features of leukemic lymphocyte precursors from acute lymphoblastic leukemia (ALL) patients. A marked heterogeneity existed between different cell lines, with a remarkable radioresistance and repair capacity in some ALL patients and an acute radiosensitivity in the absence of a detectable repair capacity in others. (U.K.)

Adhesion molecule profiles of B-cell non-Hodgkin's lymphomas in the leukemic phase

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D.M. Matos

2006-10-01

Full Text Available We evaluated the expression of 10 adhesion molecules on peripheral blood tumor cells of 17 patients with chronic lymphocytic leukemia, 17 with mantle-cell lymphoma, and 13 with nodal or splenic marginal B-cell lymphoma, all in the leukemic phase and before the beginning of any therapy. The diagnosis of B-cell non-Hodgkin's lymphomas was based on cytological, histological, immunophenotypic, and molecular biology methods. The mean fluorescence intensity of the adhesion molecules in tumor cells was measured by flow cytometry of CD19-positive cells and differed amongst the types of lymphomas. Comparison of chronic lymphocytic leukemia and mantle-cell lymphoma showed that the former presented a higher expression of CD11c and CD49c, and a lower expression of CD11b and CD49d adhesion molecules. Comparison of chronic lymphocytic leukemia and marginal B-cell lymphoma showed that the former presented a higher expression of CD49c and a lower expression of CD11a, CD11b, CD18, CD49d, CD29, and CD54. Finally, comparison of mantle-cell lymphoma and marginal B-cell lymphoma showed that marginal B-cell lymphoma had a higher expression of CD11a, CD11c, CD18, CD29, and CD54. Thus, the CD49c/CD49d pair consistently demonstrated a distinct pattern of expression in chronic lymphocytic leukemia compared with mantle-cell lymphoma and marginal B-cell lymphoma, which could be helpful for the differential diagnosis. Moreover, the distinct profiles of adhesion molecules in these diseases may be responsible for their different capacities to invade the blood stream.

Brief Report: Human Acute Myeloid Leukemia Reprogramming to Pluripotency Is a Rare Event and Selects for Patient Hematopoietic Cells Devoid of Leukemic Mutations.

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Lee, Jong-Hee; Salci, Kyle R; Reid, Jennifer C; Orlando, Luca; Tanasijevic, Borko; Shapovalova, Zoya; Bhatia, Mickie

2017-09-01

Induced pluripotent stem cell reprogramming has provided critical insights into disease processes by modeling the genetics and related clinical pathophysiology. Human cancer represents highly diverse genetics, as well as inter- and intra-patient heterogeneity, where cellular model systems capable of capturing this disease complexity would be invaluable. Acute myeloid leukemia (AML) represents one of most heterogeneous cancers and has been divided into genetic subtypes correlated with unique risk stratification over the decades. Here, we report our efforts to induce pluripotency from the heterogeneous population of human patients that represents this disease in the clinic. Using robust optimized reprogramming methods, we demonstrate that reprogramming of AML cells harboring leukemic genomic aberrations is a rare event with the exception of those with de novo mixed-lineage leukemia (MLL) mutations that can be reprogrammed and model drug responses in vitro. Our findings indicate that unlike hematopoietic cells devoid of genomic aberrations, AML cells harboring driver mutations are refractory to reprogramming. Expression of MLL fusion proteins in AML cells did not contribute to induced reprogramming success, which continued to select for patient derived cells devoid of AML patient-specific aberrations. Our study reveals that unanticipated blockades to achieving pluripotency reside within the majority of transformed AML patient cells. Stem Cells 2017;35:2095-2102. © 2017 AlphaMed Press.

Effect of pentoxifylline on P-glycoprotein mediated vincristine resistance of L1210 mouse leukemic cell line

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Breier, A.; Uhrik, B.; Barancik, M.; Stefankova, Z.; Tribulova, N.

1994-01-01

Effect of pentoxifylline (PTX) on vincristine (VCR) resistance of multidrug resistant L1210/VCR mouse leukemic cell line was studied. Reversal effect of PTX (in concentration 50-150 mg dm -3 ) on vincristine resistance, i.e. potentiation of vincristine cytotoxicity on L1210/VCR cells by PTX was found. PTX alone in the above concentration did not exert any significant effect on sensitive or resistant cell lines in the absence of vincristine. Resistance of L1210/VCR cell line was found previously to be accompanied with overexpression of drug transporting P-glycoprotein. Indeed, lower level of 3 H-vincristine accumulation by resistant L1210/VCR cell line in comparison with sensitive L1210 cell line was observed. Accumulation of 3 H-vincristine by L1210/VCR cell line was significantly increased in the presence of PTX. PTX in the same condition did not exert any considerable effect on accumulation of 3 H-vincristine by nonresistant L1210 cells. Observable morphological damage was observed in 1210/VCR cells cultivated in medium containing vincristine (0.2 mg dm -3 ) and pentoxifylline (100 mg dm -3 ) in comparison with the non-damaged cells in the presence of vincristine or pentoxifylline alone. The results obtained indicate that pentoxifylline may be considered as a reversal agent in multidrug resistance. (author)

Specific inhibition of Wee1 kinase and Rad51 recombinase: A strategy to enhance the sensitivity of leukemic T-cells to ionizing radiation-induced DNA double-strand breaks

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Havelek, Radim; Cmielova, Jana; Kralovec, Karel; Bruckova, Lenka; Bilkova, Zuzana; Fousova, Ivana; Sinkorova, Zuzana; Vavrova, Jirina; Rezacova, Martina

2014-01-01

Highlights: • Pre-treatment with the inhibitors increased the sensitivity of Jurkat cells to irradiation. • Combining both inhibitors together resulted in a G2 cell cycle arrest abrogation in Jurkat. • Jurkat cells pre-treated with inhibitors were positive for γH2AX foci 24 h upon irradiation. • Pre-treatment with Rad51 RI-1 had no effect on apoptosis induction in MOLT-4 cells. • When dosed together, the combination decreased MOLT-4 cell survival. - Abstract: Present-day oncology sees at least two-thirds of cancer patients receiving radiation therapy as a part of their anticancer treatment. The objectives of the current study were to investigate the effects of the small molecule inhibitors of Wee1 kinase II (681641) and Rad51 (RI-1) on cell cycle progression, DNA double-strand breaks repair and apoptosis following ionizing radiation exposure in human leukemic T-cells Jurkat and MOLT-4. Pre-treatment with the Wee1 681641 or Rad51 RI-1 inhibitor alone increased the sensitivity of Jurkat cells to irradiation, however combining both inhibitors together resulted in a further enhancement of apoptosis. Jurkat cells pre-treated with inhibitors were positive for γH2AX foci 24 h upon irradiation. MOLT-4 cells were less affected by inhibitors application prior to ionizing radiation exposure. Pre-treatment with Rad51 RI-1 had no effect on apoptosis induction; however Wee1 681641 increased ionizing radiation-induced cell death in MOLT-4 cells

House dust mite induces expression of intercellular adhesion molecule-1 in EoL-1 human eosinophilic leukemic cells.

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Kwon, Byoung Chul; Sohn, Myung Hyun; Kim, Kyung Won; Kim, Eun Soo; Kim, Kyu-Earn; Shin, Myeong Heon

2007-10-01

The house dust mite (HDM) is considered to be the most common indoor allergen associated with bronchial asthma. In this study, we investigated whether crude extract of the HDM Dermatophagoides farinae could activate human eosinophilic leukemic cells (EoL-1) to induce upregulation of cell-surface adhesion molecules. When EoL-1 cells were incubated with D. farinae extract, expression of intercellular adhesion molecule-1 (ICAM-1) significantly increased on the cell surfaces compared to cells incubated with medium alone. In contrast, surface expression of CD11b and CD49d in EoL-1 cells was not affected by D. farinae extract. In addition, pretreatment of cells with NF-kappaB inhibitor (MG-132) or JNK inhibitor (SP600125) significantly inhibited ICAM-1 expression promoted by HDM extract. However, neither p38 MAP kinase inhibitor nor MEK inhibitor prevented HDM-induced ICAM-1 expression in EoL-1 cells. These results suggest that crude extract of D. farinae induces ICAM-1 expression in EoL-1 cells through signaling pathways involving both NF-kappaB and JNK.

Proteoglycan biosynthesis in murine monocytic leukemic (M1) cells before and after differentiation

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McQuillan, D.J.; Yanagishita, M.; Hascall, V.C.; Bickel, M.

1989-01-01

Murine monocytic leukemic (M1) cells were cultured in the presence of [ 3 H]glucosamine and [ 35 S]sulfate. Labeled proteoglycans were purified by anion exchange chromatography and characterized by gel filtration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis in combination with chemical and enzymatic degradation. M1 cells synthesize a single predominant species of proteoglycan which distributes almost equally between the cell and medium after 17 h labeling. The cell-associated proteoglycan has an overall size of about 135 kDa and contains three to five chondroitin sulfate chains (28-31 kDa each) attached to a chondroitinase-generated core protein of 28 kDa. The synthesis and subsequent secretion of this proteoglycan was enhanced 4-5-fold in cells induced to differentiate into macrophages. This was not a phenomenon of arrest in the G0/G1 stage of the cell cycle, since density inhibited undifferentiated cells arrested at this stage did not increase proteoglycan synthesis. The chondroitin sulfate chains contained exclusively chondroitin 4- and 6-sulfate; however, the ratio of these two disaccharides differed between the medium- and cell-associated proteoglycans, and changed during progression of the cells into a fully differentiated phenotype. Pulse-chase kinetics indicate the presence of two distinct pools of proteoglycan; one that is secreted very rapidly from the cell after a approximately 1-h lag, and a second pool that is turned over in the cell with a half-time of approximately 3.5 h. Subtle differences in the glycosylation patterns of the medium- and cell-associated species are consistent with synthesis of two pools. Papain digestion suggests that the chondroitin sulfate chains are clustered on a small protease resistant peptide. The data suggest that this proteoglycan is similar to the serglycin proteoglycan family

Genomic Profiling of a Human Leukemic Monocytic Cell-Line (THP-1 Exposed to Alpha Particle Radiation

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Vinita Chauhan

2012-01-01

Full Text Available This study examined alpha (α- particle radiation effects on global changes in gene expression in human leukemic monocytic cells (THP-1 for the purposes of mining for candidate biomarkers that could be used for the development of a biological assessment tool. THP-1 cells were exposed to α-particle radiation at a dose range of 0 to 1.5 Gy. Twenty-four hours and three days after exposure gene expression was monitored using microarray technology. A total of 16 genes were dose responsive and classified as early onset due to their expression 24 h after exposure. Forty-eight transcripts were dose responsive and classified as late-onset as they were expressed 72 h after exposure. Among these genes, 6 genes were time and dose responsive and validated further using alternate technology. These transcripts were upregulated and associated with biological processes related to immune function, organelle stability and cell signalling/communication. This panel of genes merits further validation to determine if they are strong candidate biomarkers indicative of α-particle exposure.

Glucocorticoid receptors on leukemic cells as evidenced by dexamethasone-induced cytolysis and /sup 3/H-dexamethasone binding

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Thraenhardt, H; Haefer, R; Zintl, F

1987-01-01

The presence of glucocorticoid receptors on the leukemic cells of 33 patients affected with acute lymphatic leukemia (ALL) and 6 patients affected with acute myeloic leukemia (AML) was investigated by dexamethasone-induced cytolysis and (/sup 3/H)-dexamethasone binding. The tests undertaken proved that after 20 hours of incubation 9 of 26 non-T-non-B-ALL (c-ALL and unclassified ALL) and 2 of AML were lysed with dexamethasone; blood lymphocytes and bone marrow leukocytes of healthy donors, however, were not affected. Non-T-non-B-ALL and AML were able to bind essentially more (/sup 3/H)-dexamethasone than T-ALL. There existed no correlation between dexamethasone binding and dexamethasone-induced cytolysis.

Effects of buffers and pH on in vitro binding of 67Ga by L1210 leukemic cells

International Nuclear Information System (INIS)

Glickson, J.D.; Webb, J.; Gams, R.A.

1974-01-01

The effect of sodium nitrate and a series of buffers on in vitro 67 Ga binding to L1210 leukemic cells at pH 6.8 +- 0.2 and 37 0 at concentrations of 10 -7 to 10 -2 M has been investigated. The relative ability of these agents to inhibit cellular incorporation of 67 Ga is given. Inhibition probably results from formation of gallium(III) complexes which are either impermeable to the tumor membrane or which compete with intracellular receptor complexes. However, direct interaction of buffers with the cell membrane or with gallium(III) receptors, as well as effects of buffers on cellular metabolism, have not been excluded. A monotonic decrease in the cellular incorporation of 67 Ga occurs between pH 6.2 and 7.8 in the presence of the inert buffer, 10 -2 M morpholinopropane sulfonic acid. (U.S.)

Reduced hematopoietic stem cell frequency predicts outcome in acute myeloid leukemia

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Wang, Wenwen; Stiehl, Thomas; Raffel, Simon; Hoang, Van T.; Hoffmann, Isabel; Poisa-Beiro, Laura; Saeed, Borhan R.; Blume, Rachel; Manta, Linda; Eckstein, Volker; Bochtler, Tilmann; Wuchter, Patrick; Essers, Marieke; Jauch, Anna; Trumpp, Andreas; Marciniak-Czochra, Anna; Ho, Anthony D.; Lutz, Christoph

2017-01-01

In patients with acute myeloid leukemia and low percentages of aldehyde-dehydrogenase-positive cells, non-leukemic hematopoietic stem cells can be separated from leukemic cells. By relating hematopoietic stem cell frequencies to outcome we detected poor overall- and disease-free survival of patients with low hematopoietic stem cell frequencies. Serial analysis of matched diagnostic and follow-up samples further demonstrated that hematopoietic stem cells increased after chemotherapy in patients who achieved durable remissions. However, in patients who eventually relapsed, hematopoietic stem cell numbers decreased dramatically at the time of molecular relapse demonstrating that hematopoietic stem cell levels represent an indirect marker of minimal residual disease, which heralds leukemic relapse. Upon transplantation in immune-deficient mice cases with low percentages of hematopoietic stem cells of our cohort gave rise to leukemic or no engraftment, whereas cases with normal hematopoietic stem cell levels mostly resulted in multi-lineage engraftment. Based on our experimental data, we propose that leukemic stem cells have increased niche affinity in cases with low percentages of hematopoietic stem cells. To validate this hypothesis, we developed new mathematical models describing the dynamics of healthy and leukemic cells under different regulatory scenarios. These models suggest that the mechanism leading to decreases in hematopoietic stem cell frequencies before leukemic relapse must be based on expansion of leukemic stem cells with high niche affinity and the ability to dislodge hematopoietic stem cells. Thus, our data suggest that decreasing numbers of hematopoietic stem cells indicate leukemic stem cell persistence and the emergence of leukemic relapse. PMID:28550184

Reduced hematopoietic stem cell frequency predicts outcome in acute myeloid leukemia.

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Wang, Wenwen; Stiehl, Thomas; Raffel, Simon; Hoang, Van T; Hoffmann, Isabel; Poisa-Beiro, Laura; Saeed, Borhan R; Blume, Rachel; Manta, Linda; Eckstein, Volker; Bochtler, Tilmann; Wuchter, Patrick; Essers, Marieke; Jauch, Anna; Trumpp, Andreas; Marciniak-Czochra, Anna; Ho, Anthony D; Lutz, Christoph

2017-09-01

In patients with acute myeloid leukemia and low percentages of aldehyde-dehydrogenase-positive cells, non-leukemic hematopoietic stem cells can be separated from leukemic cells. By relating hematopoietic stem cell frequencies to outcome we detected poor overall- and disease-free survival of patients with low hematopoietic stem cell frequencies. Serial analysis of matched diagnostic and follow-up samples further demonstrated that hematopoietic stem cells increased after chemotherapy in patients who achieved durable remissions. However, in patients who eventually relapsed, hematopoietic stem cell numbers decreased dramatically at the time of molecular relapse demonstrating that hematopoietic stem cell levels represent an indirect marker of minimal residual disease, which heralds leukemic relapse. Upon transplantation in immune-deficient mice cases with low percentages of hematopoietic stem cells of our cohort gave rise to leukemic or no engraftment, whereas cases with normal hematopoietic stem cell levels mostly resulted in multi-lineage engraftment. Based on our experimental data, we propose that leukemic stem cells have increased niche affinity in cases with low percentages of hematopoietic stem cells. To validate this hypothesis, we developed new mathematical models describing the dynamics of healthy and leukemic cells under different regulatory scenarios. These models suggest that the mechanism leading to decreases in hematopoietic stem cell frequencies before leukemic relapse must be based on expansion of leukemic stem cells with high niche affinity and the ability to dislodge hematopoietic stem cells. Thus, our data suggest that decreasing numbers of hematopoietic stem cells indicate leukemic stem cell persistence and the emergence of leukemic relapse. Copyright© 2017 Ferrata Storti Foundation.

Do endothelial cells belong to the primitive stem leukemic clone in CML? Role of extracellular vesicles.

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Ramos, Teresa L; Sánchez-Abarca, Luis Ignacio; López-Ruano, Guillermo; Muntión, Sandra; Preciado, Silvia; Hernández-Ruano, Montserrat; Rosado, Belén; de las Heras, Natalia; Chillón, M Carmen; Hernández-Hernández, Ángel; González, Marcos; Sánchez-Guijo, Fermín; Del Cañizo, Consuelo

2015-08-01

The expression of BCR-ABL in hematopoietic stem cells is a well-defined primary event in chronic myeloid leukemia (CML). Some reports have described the presence of BCR-ABL on endothelial cells from CML patients, suggesting the origin of the disease in a primitive hemangioblastic cell. On the other hand, extracellular vesicles (EVs) released by CML leukemic cells are involved in the angiogenesis modulation process. In the current work we hypothesized that EVs released from BCR-ABL(+) cells may carry inside the oncogene that can be transferred to endothelial cells leading to the expression of both BCR-ABL transcript and the oncoprotein. EVs from K562 cells and plasma of newly diagnosed CML patients were isolated by ultracentrifugation. RT-PCR analysis detected the presence of BCR-ABL RNA in the EVs isolated from both K562 cells and plasma of CML patients. The incorporation of these EVs into endothelial cells was demonstrated by flow cytometry and fluorescence microscopy showed that after 24h of incubation most EVs were incorporated. BCR-ABL transcripts were detected in all experiments on endothelial cells incubated with EVs from both sources. The presence of BCR-ABL on endothelial cells incubated with Philadelphia(+) EVs was also confirmed by Western blot assays. In summary, endothelial cells acquire BCR-ABL RNA and the oncoprotein after incubation with EVs released from Ph(+) positive cells (either from K562 cells or from plasma of newly diagnosed CML patients). This results challenge the hypothesis that endothelial cells may be part of the Philadelphia(+) clone in CML. Copyright © 2015 Elsevier Ltd. All rights reserved.

Stable curcumin-loaded polymeric micellar formulation for enhancing cellular uptake and cytotoxicity to FLT3 overexpressing EoL-1 leukemic cells.

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Tima, Singkome; Anuchapreeda, Songyot; Ampasavate, Chadarat; Berkland, Cory; Okonogi, Siriporn

2017-05-01

The present study aims to develop a stable polymeric micellar formulation of curcumin (CM) with improved solubility and stability, and that is suitable for clinical applications in leukemia patients. CM-loaded polymeric micelles (CM-micelles) were prepared using poloxamers. The chemical structure of the polymers influenced micellar properties. The best formulation of CM-micelles, namely CM-P407, was obtained from poloxamer 407 at drug to polymer ratio of 1:30 and rehydrated with phosphate buffer solution pH 7.4. CM-P407 exhibited the smallest size of 30.3±1.3nm and highest entrapment efficiency of 88.4±4.1%. When stored at -80°C for 60days, CM-P407 retained high protection of CM and had no significant size change. In comparison with CM solution in dimethyl sulfoxide (CM-DMSO), CM kinetic degradation in both formulations followed a pseudo-first-order reaction, but the half-life of CM in CM-P407 was approx. 200 times longer than in CM-DMSO. Regarding the activity against FLT3 overexpressing EoL-1 leukemic cells, CM-P407 showed higher cytotoxicity than CM-DMSO. Moreover, intracellular uptake to leukemic cells of CM-P407 was 2-3 times greater than that of CM-DMSO. These promising results for CM-P407 will be further investigated in rodents and in clinical studies for leukemia treatment. Copyright © 2017 Elsevier B.V. All rights reserved.

Delayed expression of apoptosis in X-irradiated human leukemic MOLT-4 cells transfected with mutant p53

International Nuclear Information System (INIS)

Nakano, Hisako; Yonekawa, Hiromichi; Shinohara, Kunio

2003-01-01

The effects of X-rays on cell survival, apoptosis, and long-term response in the development of cell death as measured by the dye exclusion test were studied in human leukemic MOLT-4 cells (p53 wild-type) stably transfected with a mutant p53 cDNA expression vector. Cell survival, as determined from colony-forming ability, was increased in an expression level dependent manner, but the increase was partial even with the highest-expressing clone (B3). This contrasts with the prior observation that cell death and apoptosis in B3 are completely inhibited at 24 h after irradiation with 1.8 Gy of X-rays. The examination of B3 cells incubated for longer than 24 h after X-irradiation showed a delay in the induction of cell death and apoptosis. Western blot analysis revealed that the time required to reach the highest level of wild-type p53 protein in B3 was longer than the time in MOLT-4 and that the p53 may be stabilized by the phosphorylation at Ser-15. These results suggest that the introduction of mutant p53 into MOLT-4 merely delays the development of apoptosis, during which the cells could repair the damage induced by X-rays, and results in the partial increase in cell survival. (author)

Oxidative damage of U937 human leukemic cells caused by hydroxyl radical results in singlet oxygen formation.

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Marek Rác

Full Text Available The exposure of human cells to oxidative stress leads to the oxidation of biomolecules such as lipids, proteins and nuclei acids. In this study, the oxidation of lipids, proteins and DNA was studied after the addition of hydrogen peroxide and Fenton reagent to cell suspension containing human leukemic monocyte lymphoma cell line U937. EPR spin-trapping data showed that the addition of hydrogen peroxide to the cell suspension formed hydroxyl radical via Fenton reaction mediated by endogenous metals. The malondialdehyde HPLC analysis showed no lipid peroxidation after the addition of hydrogen peroxide, whereas the Fenton reagent caused significant lipid peroxidation. The formation of protein carbonyls monitored by dot blot immunoassay and the DNA fragmentation measured by comet assay occurred after the addition of both hydrogen peroxide and Fenton reagent. Oxidative damage of biomolecules leads to the formation of singlet oxygen as conformed by EPR spin-trapping spectroscopy and the green fluorescence of singlet oxygen sensor green detected by confocal laser scanning microscopy. It is proposed here that singlet oxygen is formed by the decomposition of high-energy intermediates such as dioxetane or tetroxide formed by oxidative damage of biomolecules.

Interleukin 1 as an autocrine growth factor for acute myeloid leukemia cells

International Nuclear Information System (INIS)

Cozzolino, F.; Rubartelli, A.; Aldinucci, D.; Sitia, R.; Torcia, M.; Shaw, A.; Di Guglielmo, R.

1989-01-01

Production of interleukin 1 (IL-1) by leukemic cells was studied in 13 cases of acute myeloid leukemia. Intracytoplasmic immunofluorescence studies showed that the cells invariably contained the cytokine. Endogenous labeling studies demonstrated that acute myeloid leukemia cells produced either only the 33-kDa propeptide or both the propeptide and the 17-kDa mature form of IL-1β. The 33-kDa propeptide IL-1α was always produced but was less frequently released. Involvement of IL-1 in leukemic cell growth was investigated using two antibodies specific for IL-1 subtypes, which inhibited spontaneous cell proliferation in the six cases studied. After acid treatment of the cells, a surface receptor for IL-1 could be demonstrated, which mediated 125 I-labeled IL-1-specific uptake by leukemic cells. Furthermore, recombinant IL-1α or IL-1β induced significant cell proliferation in 10 12 cases. The above findings were uncorrelated with the cytologic type (French-American-British classification) of leukemia. The studies suggest that IL-1 may act as an autocrine growth factor in most cases of acute myeloid leukemia

Effects of vinegar–egg on growth inhibition, differentiation human leukemic U937 cells and its immunomodulatory activity

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Shiu-Yu Wang

2018-04-01

Full Text Available Vinegar and eggs have rich nutrients. In this study, the mixed form of both derived products, vinegar–egg solution and its products (vinegar–egg concentrate and vinegar–egg condensate were chosen for an assessment of their biological activity. To further our understanding regarding the anticancer and immunomodulatory effects of vinegar–egg, we investigated its effects on the proliferation and differentiation of U937 cells. Vinegar–egg was treated using spray drying, freeze drying and vacuum concentration and used to stimulate human mononuclear cells. The conditioned media obtained from these cultures by filtration were used to treat U937 cells. Three conditioned media inhibited U937 cell growth by 22.1–67.25% more effectively than PHA-treated control (22.53%. CD11b and CD14 expression on the treated U937 cells were 29.1–45.4% and 31.6–47.2%, respectively. High levels of cytokines IL-1β, IFN-γ and TNF-α were detected in the three conditioned media. Vinegar–egg stimulates human mononuclear cells to secrete cytokines, which inhibit the growth of U937 cells and induce their differentiation. Keywords: Cytokines, Differentiation, Immunomodulatory activity, Leukemic U937 cells, Vinegar–egg

GPR84 sustains aberrant β-catenin signaling in leukemic stem cells for maintenance of MLL leukemogenesis.

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Dietrich, Philipp A; Yang, Chen; Leung, Halina H L; Lynch, Jennifer R; Gonzales, Estrella; Liu, Bing; Haber, Michelle; Norris, Murray D; Wang, Jianlong; Wang, Jenny Yingzi

2014-11-20

β-catenin is required for establishment of leukemic stem cells (LSCs) in acute myeloid leukemia (AML). Targeted inhibition of β-catenin signaling has been hampered by the lack of pathway components amenable to pharmacologic manipulation. Here we identified a novel β-catenin regulator, GPR84, a member of the G protein-coupled receptor family that represents a highly tractable class of drug targets. High GPR84 expression levels were confirmed in human and mouse AML LSCs compared with hematopoietic stem cells (HSCs). Suppression of GPR84 significantly inhibited cell growth by inducing G1-phase cell-cycle arrest in pre-LSCs, reduced LSC frequency, and impaired reconstitution of stem cell-derived mixed-lineage leukemia (MLL) AML, which represents an aggressive and drug-resistant subtype of AML. The GPR84-deficient phenotype in established AML could be rescued by expression of constitutively active β-catenin. Furthermore, GPR84 conferred a growth advantage to Hoxa9/Meis1a-transduced stem cells. Microarray analysis demonstrated that GPR84 significantly upregulated a small set of MLL-fusion targets and β-catenin coeffectors, and downregulated a hematopoietic cell-cycle inhibitor. Altogether, our data reveal a previously unrecognized role of GPR84 in maintaining fully developed AML by sustaining aberrant β-catenin signaling in LSCs, and suggest that targeting the oncogenic GPR84/β-catenin signaling axis may represent a novel therapeutic strategy for AML. © 2014 by The American Society of Hematology.

Rapid Treatment of Leukostasis in Leukemic Mantle Cell Lymphoma Using Therapeutic Leukapheresis: A Case Report

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Xuan Duc Nguyen

2011-01-01

Full Text Available We describe a case of severe leukocytosis caused by leukemic mantle cell lymphoma (MCL, complicated by leukostasis with myocardial infarction in which leukapheresis was used in the initial management. A 73-year-old male presented to the emergency department because of fatigue and thoracic pain. Blood count revealed 630 × 109/L WBC (white blood cells. The electrocardiogram showed ST-elevation with an increase of troponin and creatinine kinase. The diagnosis was ST-elevation myocardial infarction (STEMI induced and complicated by leukostasis. Immunophenotyping, morphology, cytogenetic and fluorescence-in-situ-hybridization analysis revealed the diagnosis of a blastoid variant of MCL. To remove leukocytes rapidly, leukapheresis was performed in the intensive care unit. Based on the differential blood count with 95% blasts, which were assigned to the lymphocyte population by the automatic hematology analyzer, leukapheresis procedures were then performed with the mononuclear cell standard program on the Spectra cell separator. The patient was treated with daily leukapheresis for 3 days. The WBC count decreased to 174 × 109/L after the third leukapheresis, with a 72% reduction. After the second apheresis, treatment with vincristine, cyclophosphamide, and prednisolone was started. The patient fully recovered in the further course of the treatment. To the best of our knowledge, this is the first report on blastoid MCL with leukostasis associated with a STEMI that was successfully treated by leukapheresis. Effective harvest of circulating lymphoma cells by leukapheresis requires adaptation of instrument settings based on the results of the differential blood count prior to apheresis.

Correlation of chromosome patterns in leukemic cells of patients with exposure to chemicals and/or radiation

International Nuclear Information System (INIS)

Rowley, J.D.

1989-10-01

We have identified two new recurring translocations involving chromosome 5; one is a 3;5 translocation and the other involves a rearrangement between chromosomes 5 and 7. The first is t(3;5)(q25.1;q35). We studied five patients with AML and a t(3;5) in their leukemic cells. At diagnosis, four of the patients had a t(3;5) as their sole karyotypic anomaly; the remaining patient had additional structural and numerical abnormalities. Careful cytogenetic analysis indicated that the breakpoints of this rearrangement were 3q25.1 and 5q34, in contrast to the various breakpoints reported in earlier studies (3q21 to 3q25 and 5q31 to 5q35). The karyotypic, morphologic, and clinical characteristics of this group, as well as those of 15 previously reported patients with the t(3;5), were compared to identify any features that might warrant consideration of this anomaly as a specific syndrome. The median age of the group, 37 years, as younger than that of all patients with AML, 49 years. A preceding myelodysplastic syndrome was observed in three patients. We have no information regarding the occupation of most of these patients. Except for acute promyelocytic leukemia, each morphologic subtype occurred in these patients; however, the frequency of erythroleukemia (M6) was much greater than expected. 11 refs., 2 figs., 5 tabs

Acute Respiratory Distress Syndrome Caused by Leukemic Infiltration of the Lung

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Yao-Kuang Wu

2008-05-01

Full Text Available Respiratory distress syndrome resulting from leukemic pulmonary infiltrates is seldom diagnosed antemortem. Two 60- and 80-year-old women presented with general malaise, progressive shortness of breath, and hyperleukocytosis, which progressed to acute respiratory distress syndrome (ARDS after admission. Acute leukemia with pulmonary infection was initially diagnosed, but subsequent examinations including open lung biopsy revealed leukemic pulmonary infiltrates without infection. In one case, the clinical condition and chest radiography improved initially after combination therapy with chemotherapy for leukemia and aggressive pulmonary support. However, new pulmonary infiltration on chest radiography and hypoxemia recurred, which was consistent with acute lysis pneumopathy. Despite aggressive treatment, both patients died due to rapidly deteriorating condition. Leukemic pulmonary involvement should be considered in acute leukemia patients with non-infectious diffusive lung infiltration, especially in acute leukemia with a high blast count.

Documentation of normal and leukemic myelopoietic progenitor cells with high-resolution phase-contrast time-lapse cinematography.

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Boll, I T

2001-08-01

The high-resolution phase-contrast, time-lapse cinematography using oil immersion lenses and 16-mm film demonstrates the kinetic cell events as maturation, locomotion, mitosis, and apoptosis of cells cultivated at 37 degrees C for up to 10 days. 0.5 v/v frozen-thawed sera with presumably high cytokine concentrations were added to the plasma or agar clot. Vital progenitor cells from human bone marrow and blood have a large, bright, unstructured nucleus with a large nucleolus and a narrow rim of cytoplasm (nuclear/cytoplasmic volume ratio = 0.7). Their nuclei are 6-14 micrometer in diameter and double their volume within 8 h. Many (70%) move at a mean speed of 2 micrometer/min, and many (30%) multiply with alpha-2alpha mitoses, generating progenitor cell families. Various disturbances during the course of mitosis lead to the formation of polyploid cells, thereby yielding the megakaryocytic cell line. Some of the progenitor cells undergo asymmetric alpha-alphan mitoses: One of the two initially identical daughter cells remains a progenitor cell in the morphological sense, whereas the other daughter cell - depending on the size of its mother cell - matures in the same culture medium to form a granulocytopoietic, monocytopoietic or erythrocytopoietic cell line. - In acute myeloid leukemias (AML), the blasts and their nuclei are slightly larger than the corresponding progenitor cells and move faster (5 micrometer/min). Symmetric alpha-2alpha mitoses permit unlimited multiplication of the leukemic blasts if contact with cytotoxic lymphocytes does not render them apoptotic. This results in more stromal cells than normal. Granulocytopenia, monocytopenia, and anemia occur due to the genetic impairment of signaling control for asymmetric alpha-alphan mitoses, and thrombocytopenia occurs due to the reduction in polyploidization. Copyright 2001 S. Karger GmbH, Freiburg

Novel function of the chromosome 7 open reading frame 41 gene to promote leukemic megakaryocyte differentiation by modulating TPA-induced signaling.

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Sun, X; Lu, B; Hu, B; Xiao, W; Li, W; Huang, Z

2014-03-28

12-O-tetradecanoylphorbol-13-acetate (TPA) activates multiple signaling pathways, alters gene expression and causes leukemic cell differentiation. How TPA-induced genes contribute to leukemic cell differentiation remains elusive. We noticed that chromosome 7 open reading frame 41 (C7ORF41) was a TPA-responsive gene and its upregulation concurred with human megakaryocyte differentiation. In K562 cells, ectopic expression of C7ORF41 significantly increased CD61 expression, enhanced ERK and JNK signaling, and upregulated RUNX1 and FLI1, whereas C7ORF41 knockdown caused an opposite phenotype. These observations suggest that C7ORF41 may promote megakaryocyte differentiation partially through modulating ERK and JNK signaling that leads to upregulation of RUNX1 and FLI1. In supporting this, C7ORF41 overexpression rescued megakaryocyte differentiation blocked by ERK inhibition while JNK inhibition abrogated the upregulation of FLI1 by C7ORF41. Furthermore, we found that Y34F mutant C7ORF41 inhibited megakaryocyte differentiation. nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) was the major activator of C7ORF41 that in turn repressed NF-κB activity by inhibiting its phosphorylation at serine 536, while MAPK/ERK was the potent repressor of C7ORF41. Finally, we showed that C7ORF41 knockdown in mouse fetal liver cells impaired megakaryocyte differentiation. Taken together, we have identified the function of a novel gene C7ORF41 that forms interplaying regulatory network in TPA-induced signaling and promotes leukemic and normal megakaryocyte differentiation.

Novel function of the chromosome 7 open reading frame 41 gene to promote leukemic megakaryocyte differentiation by modulating TPA-induced signaling

International Nuclear Information System (INIS)

Sun, X; Lu, B; Hu, B; Xiao, W; Li, W; Huang, Z

2014-01-01

12-O-tetradecanoylphorbol-13-acetate (TPA) activates multiple signaling pathways, alters gene expression and causes leukemic cell differentiation. How TPA-induced genes contribute to leukemic cell differentiation remains elusive. We noticed that chromosome 7 open reading frame 41 (C7ORF41) was a TPA-responsive gene and its upregulation concurred with human megakaryocyte differentiation. In K562 cells, ectopic expression of C7ORF41 significantly increased CD61 expression, enhanced ERK and JNK signaling, and upregulated RUNX1 and FLI1, whereas C7ORF41 knockdown caused an opposite phenotype. These observations suggest that C7ORF41 may promote megakaryocyte differentiation partially through modulating ERK and JNK signaling that leads to upregulation of RUNX1 and FLI1. In supporting this, C7ORF41 overexpression rescued megakaryocyte differentiation blocked by ERK inhibition while JNK inhibition abrogated the upregulation of FLI1 by C7ORF41. Furthermore, we found that Y34F mutant C7ORF41 inhibited megakaryocyte differentiation. nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) was the major activator of C7ORF41 that in turn repressed NF-κB activity by inhibiting its phosphorylation at serine 536, while MAPK/ERK was the potent repressor of C7ORF41. Finally, we showed that C7ORF41 knockdown in mouse fetal liver cells impaired megakaryocyte differentiation. Taken together, we have identified the function of a novel gene C7ORF41 that forms interplaying regulatory network in TPA-induced signaling and promotes leukemic and normal megakaryocyte differentiation

Interaction of leukemic cells with proteins of the extracellular matrix Interações de células leucêmicas com proteínas da matriz extracelular

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Adriana Rodrigues-Anjos

2004-01-01

Full Text Available The interaction of neoplastic cells with basement membrane molecules is the first step for the dissemination of tumor cells in vivo. Leukemic cells have a great ability to spread in the host, since cells are released from the bone marrow to the circulation. In this study we analysed whether CEM, U937, K562 and HL-60 cells were able to attach to different concentrations of laminin and/or fibronectin and/or type IV collagen. Attachment to type IV collagen was low, but it increased with the addition of laminin and occurred in all four leukemic cell lines. On the other hand, attachment to fibronectin was higher, but it decreased with the addition of laminin in the assays using U937 and HL-60 cells. The combination of type IV collagen and fibronectin was a good substratum for cellular attachment. However, the addition of laminin to this substratum impaired its attachment activity in U937, HL-60 and K562. These data suggest that laminin may control cellular attachment to the extracellular matrix during leukemic dissemination in hosts in different ways.A interação de células neoplásicas com moléculas da membrana basal é a primeira etapa para a disseminação, in vivo, de células tumorais in vivo. As células leucêmicas possuem grande capacidade de espraiamento e disseminação no organismo uma vez que as mesmas são liberadas da medula óssea para a circulação. Neste trabalho avaliamos a capacidade das linhagens celulares CEM, U937, K562 and HL-60 em aderirem a uma matriz extracelular constituída por diferentes concentrações de laminina e,ou fibronectina e sobre colágeno IV. A adesão de todas a linhagens leucêmicas a colágeno IV foi baixa, mas aumentou com a associação à laminina. Por outro lado, as células U937 e HL-60 apresentaram alta ligação à fibronectina porém, foi reduzida com a adição de laminina. A associação de colágeno IV e fibronectina possibilitou um bom substrato para a adesão celular. Entretanto, a adi

Gemtuzumab Ozogamicin (GO Inclusion to Induction Chemotherapy Eliminates Leukemic Initiating Cells and Significantly Improves Survival in Mouse Models of Acute Myeloid Leukemia

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Cathy C Zhang

2018-01-01

Full Text Available Gemtuzumab ozogamicin (GO is an anti-CD33 antibody-drug conjugate for the treatment of acute myeloid leukemia (AML. Although GO shows a narrow therapeutic window in early clinical studies, recent reports detailing a modified dosing regimen of GO can be safely combined with induction chemotherapy, and the combination provides significant survival benefits in AML patients. Here we tested whether the survival benefits seen with the combination arise from the enhanced reduction of chemoresidual disease and leukemic initiating cells (LICs. Herein, we use cell line and patient-derived xenograft (PDX AML models to evaluate the combination of GO with daunorubicin and cytarabine (DA induction chemotherapy on AML blast growth and animal survival. DA chemotherapy and GO as separate treatments reduced AML burden but left significant chemoresidual disease in multiple AML models. The combination of GO and DA chemotherapy eliminated nearly all AML burden and extended overall survival. In two small subsets of AML models, chemoresidual disease following DA chemotherapy displayed hallmark markers of leukemic LICs (CLL1 and CD34. In vivo, the two chemoresistant subpopulations (CLL1+/CD117− and CD34+/CD38+ showed higher ability to self-renewal than their counterpart subpopulations, respectively. CD33 was coexpressed in these functional LIC subpopulations. We demonstrate that the GO and DA induction chemotherapy combination more effectively eliminates LICs in AML PDX models than either single agent alone. These data suggest that the survival benefit seen by the combination of GO and induction chemotherapy, nonclinically and clinically, may be attributed to the enhanced reduction of LICs.

PENGARUH EKSTRAK JAMU TERHADAP AKTIVITAS SEL NATURAL KILLER DALAM MELISIS ALUR SEL LEUKIMIA (K-562 SECARA IN VITRO [The Effects of Commercial “Jamu” Extracts on Natural Killer Cell Activity in Lysing Leukemic Cell Line (K-562 in vitro

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Elisa Veronica D.C. 2

2002-04-01

Full Text Available Natural killer (NK cell consitutes white blood cells which specifically functions in lysing tumor and virus invected cells. In this research, a commercial “Jamu” was tested to observe its effect on NK cells activity against leukemic cell lines (K562 in vitro. Jamu was extracted with hot water, diluted and added into cell cultures consisted of a mixture of human peripheric limphocyte cells, as the source of the effector NK cells, and K562 cell line i.e., the target cells which were cell line derived from human leukemia and had been labelled with H3-thymidine. The mixture of the cells were made by culturing the two cells at the ratio of 50:1 and 100 : 1, respectively. The results showed that lysing activity of NK cells in the presence of “Jamu” water extract measured as lysing percentage and lysing index increased only slightly, which were not statiscally significant. It should be considered that the test used in this research represents only a part of the lysing mechanism by NK cells against the target cells. An in vivo test for a period of time will be recessary to elucidate ffurther this NK cell activity.

DNA repair and DNA synthesis in leukemic and virus infected cells

International Nuclear Information System (INIS)

Tuschl, H.; Altmann, H.; Kovac, R.; Topaloglou, A.; Stacher, A.; Fanta, D.

1978-09-01

Autoradiographic determinations of unscheduled DNA synthesis in peripheral lymphocytes of leukemic patients showed strongly different results according to various types of disease of different forms of therapy, respectively. Similar investigations performed with lymphocytes of Herpes simplex infected persons during symptom-free intervals revealed imbalances of the repair system caused by virus infection. BND cellulose chromatography and measurement of 3 H-thymidine incorporation into single- and double stranded DNA fractions showed an increase in velocity of the rejoining process, but a decrease in total incorporation. Because of these results and the demonstration of the supercoiled structure of DNA it is suggested that virusinfections cause a faster rejoining of gaps, but at the same time leave a number of failures within DNA unrecognized. (author)

Overcoming of P-glycoprotein mediated vincristine resistance of L1210/VCR mouse leukemic cells could be induced by pentoxifylline but not by theophylline and caffeine

International Nuclear Information System (INIS)

Stefankova, Z.; Barancik, M.; Breier, A.

1996-01-01

Effects of xanthine derivatives (pentoxifylline (PTX), caffeine, theophylline, 1-methyl-3-isobutylxanthine) on P-glycoprotein mediated vincristine resistance of L1210/VCR mouse leukemic cell sub-line were studied. From the applied xanthines only PTX was found to reverse the vincristine resistance of the above cells. Moreover, only PTX, but not other xanthine, increased the accumulation of [ 3 H]vincristine by L1210/VCR cells. Thus it may be concluded that PTX-induced reversal of vincristine (VCR) resistance could not be explained from the point of known pharmacological effects of PTX that are common for other xanthines such as inhibition of phosphodiesterase activity, calcium mobilizing effect, inhibition of tumor necrosis factor α (TNF), etc. (author)

5-Aza-2'-deoxycytidine synergistic action with thymidine on leukemic cells and interaction of 5-aza-dCMP with dCMP deaminase

International Nuclear Information System (INIS)

Momparler, R.L.; Bartolucci, S.; Bouchard, J.; Momparler, L.F.; Raia, C.A.; Rossi, M.

1986-01-01

The authors observe a synergistic antineoplastic effect between 5-AZA-dCR and dTR on leukemia cells in culture. In order to understand the mechanism behind this interaction the authors investigate the effects of dTTP on the deamination of 5-aza-2'-deoxycytidine-5'-monophosphate (5-AZA-dCMP) by dCMP deaminase. The effects of 5-AZA-dCTP on this enzyme is also studied. The incorporation of tritium-5-AZA-Cdr into DNA of leukemic cells was performed. The amount of radioactivity incorproated into DNA was determined by trapping the cells on GF/C glass fiber filters and washing with cold TCA. It is shown that the modulation of the atieoplastic activity of deoxycytidine analogs by allosteric effectors such as dTTP may have the potential to increase the effectiveness of the chemotherapy for acute leukemia

Effects of in vitro Brevetoxin Exposure on Apoptosis and Cellular Metabolism in a Leukemic T Cell Line (Jurkat

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John W. Sleasman

2008-06-01

Full Text Available Harmful algal blooms (HABs of the toxic dinoflagellate, Karenia brevis, produce red tide toxins, or brevetoxins. Significant health effects associated with red tide toxin exposure have been reported in sea life and in humans, with brevetoxins documented within immune cells from many species. The objective of this research was to investigate potential immunotoxic effects of brevetoxins using a leukemic T cell line (Jurkat as an in vitro model system. Viability, cell proliferation, and apoptosis assays were conducted using brevetoxin congeners PbTx-2, PbTx-3, and PbTx-6. The effects of in vitro brevetoxin exposure on cell viability and cellular metabolism or proliferation were determined using trypan blue and MTT (1-(4,5-dimethylthiazol-2-yl-3,5- diphenylformazan, respectively. Using MTT, cellular metabolic activity was decreased in Jurkat cells exposed to 5 - 10 μg/ml PbTx-2 or PbTx-6. After 3 h, no significant effects on cell viability were observed with any toxin congener in concentrations up to 10 μg/ml. Viability decreased dramatically after 24 h in cells treated with PbTx-2 or -6. Apoptosis, as measured by caspase-3 activity, was significantly increased in cells exposed to PbTx-2 or PbTx-6. In summary, brevetoxin congeners varied in effects on Jurkat cells, with PbTx-2 and PbTx-6 eliciting greater cellular effects compared to PbTx-3.

Comparison of edge detection techniques for M7 subtype Leukemic cell in terms of noise filters and threshold value

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Abdul Salam Afifah Salmi

2017-01-01

Full Text Available This paper will focus on the study and identifying various threshold values for two commonly used edge detection techniques, which are Sobel and Canny Edge detection. The idea is to determine which values are apt in giving accurate results in identifying a particular leukemic cell. In addition, evaluating suitability of edge detectors are also essential as feature extraction of the cell depends greatly on image segmentation (edge detection. Firstly, an image of M7 subtype of Acute Myelocytic Leukemia (AML is chosen due to its diagnosing which were found lacking. Next, for an enhancement in image quality, noise filters are applied. Hence, by comparing images with no filter, median and average filter, useful information can be acquired. Each threshold value is fixed with value 0, 0.25 and 0.5. From the investigation found, without any filter, Canny with a threshold value of 0.5 yields the best result.

The variable chemotherapeutic response of Malabaricone-A in leukemic and solid tumor cell lines depends on the degree of redox imbalance.

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Manna, Alak; De Sarkar, Sritama; De, Soumita; Bauri, Ajay K; Chattopadhyay, Subrata; Chatterjee, Mitali

2015-07-15

The 'two-faced' character of reactive oxygen species (ROS) plays an important role in cancer biology by acting as secondary messengers in intracellular signaling cascades, enhancing cell proliferation and survival, thereby sustaining the oncogenic phenotype. Conversely, enhanced generation of ROS can trigger an oxidative assault leading to a redox imbalance translating into an apoptotic cell death. Intrinsically, cancer cells have higher basal levels of ROS which if supplemented by additional oxidative insult by pro-oxidants can be cytotoxic, an example being Malabaricone-A (MAL-A). MAL-A is a plant derived diarylnonanoid, purified from fruit rind of the plant Myristica malabarica whose anti-cancer activity has been demonstrated in leukemic cell lines, the modality of cell death being apoptosis. This study aimed to compare the degree of effectiveness of MAL-A in leukemic vs. solid tumor cell lines. The cytotoxicity of MAL-A was evaluated by the MTS-PMS cell viability assay in leukemic cell lines (MOLT3, K562 and HL-60) and compared with solid tumor cell lines (MCF7, A549 and HepG2); further studies then proceeded with MOLT3 vs. MCF7 and A549. The contribution of redox imbalance in MAL-A induced cytotoxicity was confirmed by pre-incubating cells with an antioxidant, N-acetyl-L-cysteine (NAC) or a thiol depletor, buthionine sulfoximine (BSO). MAL-A induced redox imbalance was quantitated by flow cytometry, by measuring the generation of ROS and levels of non protein thiols using dichlorofluorescein diacetate (CM-H2DCFDA) and 5-chloromethylfluorescein diacetate (CMFDA) respectively. The activities of glutathione peroxidase (GPx), superoxide dismutase, catalase (CAT), NAD(P)H dehydrogenase (quinone 1) NQO1 and glutathione-S-transferase GST were measured spectrophotometrically. The mitochondrial involvement of MAL-A induced cell death was measured by evaluation of cardiolipin peroxidation using 10-N-nonyl acridine orange (NAO), transition pore activity with calcein

C60 Fullerene Effects on Diphenyl-N-(trichloroacetyl)-amidophosphate Interaction with DNA In Silico and Its Cytotoxic Activity Against Human Leukemic Cell Line In Vitro

Science.gov (United States)

Grebinyk, A.; Prylutska, S.; Grynyuk, I.; Kolp, B.; Hurmach, V.; Sliva, T.; Amirkhanov, V.; Trush, V.; Matyshevska, O.; Slobodyanik, M.; Prylutskyy, Yu.; Frohme, M.; Ritter, U.

2018-03-01

New representative of carbacylamidophosphates - diphenyl-N-(trichloroacetyl)-amidophosphate (HL), which contains two phenoxy substituents near the phosphoryl group, was synthesized, identified by elemental analysis and IR and NMR spectroscopy, and tested as a cytotoxic agent itself and in combination with C60 fullerene. According to molecular simulation results, C60 fullerene and HL could interact with DNA and form a rigid complex stabilized by stacking interactions of HL phenyl groups with C60 fullerene and DNA G nucleotide, as well as by interactions of HL CCl3 group by ion-π bonds with C60 molecule and by electrostatic bonds with DNA G nucleotide. With the use of MTT test, the cytotoxic activity of HL against human leukemic CCRF-CM cells with IC50 value detected at 10 μM concentration at 72 h of cells treatment was shown. Under combined action of 16 μM C60 fullerene and HL, the value of IC50 was detected at lower 5 μM HL concentration and at earlier 48 h period of incubation, besides the cytotoxic effect of HL was observed at a low 2.5 μM concentration at which HL by itself had no influence on cell viability. Binding of C60 fullerene and HL with minor DNA groove with formation of a stable complex is assumed to be one of the possible reasons of their synergistic inhibition of CCRF-CEM cells proliferation. Application of C60 fullerene in combination with 2.5 μM HL was shown to have no harmful effect on structural stability of blood erythrocytes membrane. Thus, combined action of C60 fullerene and HL in a low concentration potentiated HL cytotoxic effect against human leukemic cells and was not followed by hemolytic effect.

Limiting-dilution analysis for the determination of leukemic cell frequencies after bone marrow decontamination with mafosfamide or merocyanine 540

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Porcellini, A.; Talevi, N.; Marchetti-Rossi, M.T.; Palazzi, M.; Manna, A.; Sparaventi, G.; Delfini, C.; Valentini, M.

1987-11-01

To stimulate a leukemia remission marrow, cell suspensions of normal human bone marrow were mixed with human acute lymphoblastic or myelogenous leukemic cells of the CCRF-SF, Nalm-6, and K-562 lines. The cell mixtures were incubated in vitro with mafosfamide (AZ) or with the photoreactive dye merocyanine 540 (MC-540). A quantity of 10(4) cells of the treated suspensions was dispensed into microculture plates, and graded cell numbers of the line used to contaminate the normal marrow were added. Limiting-dilution analysis was used to estimate the frequency of leukemia cells persisting after treatment with the decontaminating agents. Treatment with AZ or MC-540 produced a total elimination (ie, 6 logs or 5.3 logs respectively) of B cell acute leukemia cells (CCRF-SB), whereas nearly 1.7 logs and 2 logs of K-562 acute myelogenous blasts were still present in the cell mixtures after treatment with MC-540 and AZ, respectively. Treatment of the Nalm-6-contaminated cell mixtures with AZ resulted in 100% elimination of clonogenic cells, whereas nearly 80% decontamination was obtained with MC-540. Our results suggest that treatment with AZ could be an effective method of eliminating clonogenic tumor cells from human bone marrow. MC-540, shown by previous studies to spare sufficient pluripotential stem cells to ensure hemopoietic reconstitution in the murine model and in clinical application, has comparable effects and merits trials for possible clinical use in autologous bone marrow transplantation.

Limiting-dilution analysis for the determination of leukemic cell frequencies after bone marrow decontamination with mafosfamide or merocyanine 540

International Nuclear Information System (INIS)

Porcellini, A.; Talevi, N.; Marchetti-Rossi, M.T.; Palazzi, M.; Manna, A.; Sparaventi, G.; Delfini, C.; Valentini, M.

1987-01-01

To stimulate a leukemia remission marrow, cell suspensions of normal human bone marrow were mixed with human acute lymphoblastic or myelogenous leukemic cells of the CCRF-SF, Nalm-6, and K-562 lines. The cell mixtures were incubated in vitro with mafosfamide (AZ) or with the photoreactive dye merocyanine 540 (MC-540). A quantity of 10(4) cells of the treated suspensions was dispensed into microculture plates, and graded cell numbers of the line used to contaminate the normal marrow were added. Limiting-dilution analysis was used to estimate the frequency of leukemia cells persisting after treatment with the decontaminating agents. Treatment with AZ or MC-540 produced a total elimination (ie, 6 logs or 5.3 logs respectively) of B cell acute leukemia cells (CCRF-SB), whereas nearly 1.7 logs and 2 logs of K-562 acute myelogenous blasts were still present in the cell mixtures after treatment with MC-540 and AZ, respectively. Treatment of the Nalm-6-contaminated cell mixtures with AZ resulted in 100% elimination of clonogenic cells, whereas nearly 80% decontamination was obtained with MC-540. Our results suggest that treatment with AZ could be an effective method of eliminating clonogenic tumor cells from human bone marrow. MC-540, shown by previous studies to spare sufficient pluripotential stem cells to ensure hemopoietic reconstitution in the murine model and in clinical application, has comparable effects and merits trials for possible clinical use in autologous bone marrow transplantation

Alkaloid-rich fraction of Himatanthus lancifolius contains anti-tumor agents against leukemic cells

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Melissa Pires de Lima

2010-06-01

Full Text Available The effects of the alkaloid-rich fraction of Himatanthus lancifolius (Müll. Arg Woodson on normal marrow cells and leukemic cell lines were investigated. After 48 h exposure, the proliferation assay showed significant cell growth inhibition for Daudi (0.1-10 µg/mL, K-562 (1-10 µg/mL, and REH cells (10-100 µg/mL, yet was inert for normal marrow cells. A similar inhibition profile was observed in clonogenic assays. This alkaloid-rich fraction, in which uleine is the main compound, showed no signs of toxicity to any cells up to 10 µg/mL. Cell feature analyses after induction of differentiation showed maintenance of the initial phenotype. Flow cytometric expression of Annexin-V and 7-AAD in K-562 and Daudi cells has indicated that the cells were not undergoing apoptosis or necrosis, suggesting cytostatic activity for tumor cellsOs efeitos da fração rica em alcalóides indólicos de Himatanthus lancifolius (Müll. Arg Woodson sobre células normais de medula óssea e linhagens celulares leucêmicas foram investigados. Após 48 horas de exposição, os ensaios de proliferação demonstraram efeitos inibitórios significativos para as linhagens Daudi (0,1-10 µg/mL, K-562 (1-10 µg/mL e REH (10-100 µg/mL, enquanto mostrou-se inerte sobre células normais de medula óssea. Os perfis de inibição se repetiram nos ensaios clonogênicos. A fração rica em alcalóides, na qual a uleína é a substância majoritária, não demonstrou toxicidade até a dose de 10 µg/mL para nenhuma das células incluídas no estudo. Da mesma forma, não se observou influência dessa fração sobre a diferenciação celular dessas linhagens, mas manutenção de seu estado maturacional inicial. O conjunto de dados descritos associado à baixa co-expressão de anexina-V e 7-AAD sugerem que esta fração exerce atividade citostática para células tumorais.

SETBP1 mutations drive leukemic transformation in ASXL1-mutated MDS.

Science.gov (United States)

Inoue, D; Kitaura, J; Matsui, H; Hou, H-A; Chou, W-C; Nagamachi, A; Kawabata, K C; Togami, K; Nagase, R; Horikawa, S; Saika, M; Micol, J-B; Hayashi, Y; Harada, Y; Harada, H; Inaba, T; Tien, H-F; Abdel-Wahab, O; Kitamura, T

2015-04-01

Mutations in ASXL1 are frequent in patients with myelodysplastic syndrome (MDS) and are associated with adverse survival, yet the molecular pathogenesis of ASXL1 mutations (ASXL1-MT) is not fully understood. Recently, it has been found that deletion of Asxl1 or expression of C-terminal-truncating ASXL1-MTs inhibit myeloid differentiation and induce MDS-like disease in mice. Here, we find that SET-binding protein 1 (SETBP1) mutations (SETBP1-MT) are enriched among ASXL1-mutated MDS patients and associated with increased incidence of leukemic transformation, as well as shorter survival, suggesting that SETBP1-MT play a critical role in leukemic transformation of MDS. We identify that SETBP1-MT inhibit ubiquitination and subsequent degradation of SETBP1, resulting in increased expression. Expression of SETBP1-MT, in turn, inhibited protein phosphatase 2A activity, leading to Akt activation and enhanced expression of posterior Hoxa genes in ASXL1-mutant cells. Biologically, SETBP1-MT augmented ASXL1-MT-induced differentiation block, inhibited apoptosis and enhanced myeloid colony output. SETBP1-MT collaborated with ASXL1-MT in inducing acute myeloid leukemia in vivo. The combination of ASXL1-MT and SETBP1-MT activated a stem cell signature and repressed the tumor growth factor-β signaling pathway, in contrast to the ASXL1-MT-induced MDS model. These data reveal that SETBP1-MT are critical drivers of ASXL1-mutated MDS and identify several deregulated pathways as potential therapeutic targets in high-risk MDS.

F-box protein FBXL2 targets cyclin D2 for ubiquitination and degradation to inhibit leukemic cell proliferation

Science.gov (United States)

Chen, Bill B.; Glasser, Jennifer R.; Coon, Tiffany A.; Zou, Chunbin; Miller, Hannah L.; Fenton, Moon; McDyer, John F.; Boyiadzis, Michael

2012-01-01

Hematologic maligancies exhibit a growth advantage by up-regulation of components within the molecular apparatus involved in cell-cycle progression. The SCF (Skip-Cullin1-F-box protein) E3 ligase family provides homeostatic feedback control of cell division by mediating ubiquitination and degradation of cell-cycle proteins. By screening several previously undescribed E3 ligase components, we describe the behavior of a relatively new SCF subunit, termed FBXL2, that ubiquitinates and destabilizes cyclin D2 protein leading to G0 phase arrest and apoptosis in leukemic and B-lymphoblastoid cell lines. FBXL2 expression was strongly suppressed, and yet cyclin D2 protein levels were robustly expressed in acute myelogenous leukemia (AML) and acute lymphoblastic leukemia (ALL) patient samples. Depletion of endogenous FBXL2 stabilized cyclin D2 levels, whereas ectopically expressed FBXL2 decreased cyclin D2 lifespan. FBXL2 did not bind a phosphodegron within its substrate, which is typical of other F-box proteins, but uniquely targeted a calmodulin-binding signature within cyclin D2 to facilitate its polyubiquitination. Calmodulin competes with the F-box protein for access to this motif where it bound and protected cyclin D2 from FBXL2. Calmodulin reversed FBXL2-induced G0 phase arrest and attenuated FBXL2-induced apoptosis of lymphoblastoid cells. These results suggest an antiproliferative effect of SCFFBXL2 in lymphoproliferative malignancies. PMID:22323446

The collagen receptor uPARAP/Endo180 as a novel target for antibody-drug conjugate mediated treatment of mesenchymal and leukemic cancers

DEFF Research Database (Denmark)

Nielsen, Christoffer Fagernæs; van Putten, Sander Maarten; Lund, Ida Katrine

2017-01-01

A key task in developing the field of personalized cancer therapy is the identification of novel molecular targets that enable treatment of cancers not susceptible to other means of specific therapy. The collagen receptor uPARAP/Endo180 is overexpressed by malignant cells in several non-epithelia......A key task in developing the field of personalized cancer therapy is the identification of novel molecular targets that enable treatment of cancers not susceptible to other means of specific therapy. The collagen receptor uPARAP/Endo180 is overexpressed by malignant cells in several non...... into the endosomal-lysosomal system, thus opening a potential route of entry into receptor-positive cells. This combination of specific expression and endocytic function appears well suited for targeting of uPARAP/Endo180-positive cancers by antibody-drug conjugate (ADC) mediated drug delivery. Therefore, we...... model with human uPARAP/Endo180-positive leukemic cells, obtaining a complete cure of all tested mice following intravenous ADC treatment with no sign of adverse effects. Our study identifies uPARAP/Endo180 as a promising target for novel therapy against several highly malignant cancer types....

Molecular mechanisms associated with leukemic transformation of MPL-mutant myeloproliferative neoplasms

DEFF Research Database (Denmark)

Beer, Philip A; Ortmann, Christina A; Stegelmann, Frank

2010-01-01

Somatic activating mutations in MPL, the thrombopoietin receptor, occur in the myeloproliferative neoplasms, although virtually nothing is known about their role in evolution to acute myeloid leukemia. In this study, the MPL T487A mutation, identified in de novo acute myeloid leukemia......, was not detected in 172 patients with a myeloproliferative neoplasm. In patients with a prior MPL W515L-mutant myeloproliferative neoplasm, leukemic transformation was accompanied by MPL-mutant leukemic blasts, was seen in the absence of prior cytoreductive therapy and often involved loss of wild-type MPL...

Modulation of P-glycoprotein-mediated multidrug resistance in K562 leukemic cells by indole-3-carbinol

International Nuclear Information System (INIS)

Arora, Annu; Seth, Kavita; Kalra, Neetu; Shukla, Yogeshwer

2005-01-01

Resistance to chemotherapeutic drugs is one of the major problems in the treatment of cancer. P-glycoprotein (P-gp) encoded by the mdr gene is a highly conserved protein, acts as a multidrug transporter, and has a major role in multiple drug resistance (MDR). Targeting of P-gp by naturally occurring compounds is an effective strategy to overcome MDR. Indole-3-carbinol (I3C), a glucosinolates present in cruciferous vegetables, is a promising chemopreventive agent as it is reported to possess antimutagenic, antitumorigenic, and antiestrogenic properties in experimental studies. In the present investigation, the potential of I3C to modulate P-gp expression was evaluated in vinblastine (VBL)-resistant K562 human leukemic cells. The resistant K562 cells (K562/R10) were found to be cross-resistant to vincristine (VCR), doxorubicin (DXR), and other antineoplastic agents. I3C at a nontoxic dose (10 x 10 -3 M) enhanced the cytotoxic effects of VBL time dependently in VBL-resistant human leukemia (K562/R10) cells but had no effect on parent-sensitive cells (K562/S). The Western blot analysis of K 562/R 10 cells showed that I3C downregulates the induced levels of P-gp in resistant cells near to normal levels. The quantitation of immunocytochemically stained K562/R10 cells showed 24%, 48%, and 80% decrease in the levels of P-gp by I3C for 24, 48, and 72 h of incubation. The above features thus indicate that I3C could be used as a novel modulator of P-gp-mediated multidrug resistance in vitro and may be effective as a dietary adjuvant in the treatment of MDR cancers

Pre leukemic granulocytic sarcoma of vagina: a case report with review of literature

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Lakshminarasimhan, Srinivasan; Doval, D.C.; Rajashekhar, Usha; Mukherjee, Geethashree; Kannan, V.; Lakshmi Devi; Bapsy, P.P.

1996-01-01

Granulocytic sarcoma is an extramedullary tumor of malignant granulocytic progenitor cells, that may precede the onset of acute myeloid leukemia or appear during the leukemic manifestation or blastic crisis of chronic myeloproliferative disorders. A case of granulocytic sarcoma of vagina in a 27 year old woman treated with local radiotherapy is described. After seven months of follow up she developed acute myeloid leukemia. The case has been presented in view of its rarity and discussed in light of the available literature. (author). 13 refs., 1 fig

Constitutive STAT3-activation in Sezary syndrome: tyrphostin AG490 inhibits STAT3-activation, interleukin-2 receptor expression and growth of leukemic Sezary cells

DEFF Research Database (Denmark)

Eriksen, K W; Kaltoft, K; Mikkelsen, G

2001-01-01

are IL-2Ralpha negative. An aberrant expression of IL-2Ralpha has recently been described in cutaneous T-cell lymphoma (CTCL). Here, we study the regulation of IL-2Ralpha expression and STATs in a tumor cell line obtained from peripheral blood from a patient with Sezary syndrome (SS), a leukemic variant...... of CTCL. We show that (1) STAT3 (a transcription factor known to regulate IL-2Ralpha transcription) is constitutively tyrosine-phosphorylated in SS tumor cells, but not in non-malignant T cells; (2) STAT3 binds constitutively to a STAT-binding sequence in the promotor of the IL-2Ralpha gene; (3) the Janus...... kinase inhibitor, tyrphostine AG490, inhibits STAT3 activation, STAT3 DNA binding, and IL-2Ralpha mRNA and protein expression in parallel; and (4) tyrphostine AG490 inhibits IL-2 driven mitogenesis and triggers apoptosis in SS tumor cells. In conclusion, we provide the first example of a constitutive...

Determination of Elements in Normal and Leukemic Human Whole Blood by Neutron Activation Analysis

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Brune, D; Frykberg, B; Samsahl, K; Wester, P O

1961-11-15

By means of gamma-spectrometry the following elements were simultaneously determined in normal and leukemic human whole blood: Cu, Mn, Zn, Sr, Na, P, Ca, Rb, Cd, Sb, Au, Cs and Fe. Chemical separations were performed according to a group separation method using ion-exchange technique. No significant difference between the concentrations of the elements in normal- and leukemic blood was observed.

Determination of Elements in Normal and Leukemic Human Whole Blood by Neutron Activation Analysis

International Nuclear Information System (INIS)

Brune, D.; Frykberg, B.; Samsahl, K.; Wester, P.O.

1961-11-01

By means of gamma-spectrometry the following elements were simultaneously determined in normal and leukemic human whole blood: Cu, Mn, Zn, Sr, Na, P, Ca, Rb, Cd, Sb, Au, Cs and Fe. Chemical separations were performed according to a group separation method using ion-exchange technique. No significant difference between the concentrations of the elements in normal- and leukemic blood was observed

Surface topography of hairy cell leukemia cells compared to other leukemias as seen by scanning electron microscopy.

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Polliack, Aaron; Tadmor, Tamar

2011-06-01

This short review deals with the ultrastructural surface architecture of hairy cell leukemia (HCL) compared to other leukemic cells, as seen by scanning electron microscopy (SEM). The development of improved techniques for preparing blood cells for SEM in the 1970s readily enabled these features to be visualized more accurately. This review returns us to the earlier history of SEM, when the surface topography of normal and neoplastic cells was visualized and reported for the first time, in an era before the emergence and use of monoclonal antibodies and flow cytometry, now used routinely to define cells by their immunophenotype. Surface microvilli are characteristic for normal and leukemic lymphoid cells, myelo-monocytic cells lack microvilli and show surface ruffles, while leukemic plasma and myeloma cells and megakaryocytes display large surface blebs. HCL cell surfaces are complex and typically 'hybrid' in nature, displaying both lymphoid and monocytic features with florid ruffles of varying sizes interspersed with clumps of short microvilli cytoplasm. The surface features of other leukemic cells and photomicrographs of immuno-SEM labeling of cells employing antibodies and colloidal gold, reported more than 20 years ago, are shown.

Transformation of bone marrow stem-cells and radiation-induced myeloid leukemia in mice

International Nuclear Information System (INIS)

Hirashima, K.; Bessho, M.; Hayata, I.; Nara, N.; Kawase, Y.; Ohtani, M.

1982-01-01

After a single whole-body X-irradiation of 300R to male RFM/MsNrs strain mice, the occurrence of myeloid leukemia initiated since four months and ceased at eleven months after irradiation. The cumulative incidence reached 24.5%. A time course study on the kinetics of pluripotential stem-cells (CFU-S) and granuloid committed stem-cells (CFU-C) in the marrow after 300R was also performed. The repopulation of CFU-S was accomplished within one month whereas that of CFU-C needed 210 days after irradiation. The incidence of leukemia was very rare after the complete repopulation of CFU-C. Simultaneously, collected spleen cells from the irradiated mice without overt leukemia were transplanted into 300-600R irradiated recipients of another sex. Three months thereafter, recipients were sacrificed to detect leukemic changes and the origin of leukemic cells by chromosome analysis. The results revealed that leukemic cell transformation of donor cells began 18 days after irradiation and on an average, 37.1% of the irradiated mice carried potentially leukemic cells for seven months after exposure, whereas none of the unirradiated mice carried leukemic cells at 7 months after irradiation. To investigate host factor(s) contributing to the proliferation of leukemic cells, the suppression of cellular immunity after 300R was measured by GVH mortality assay. However, the recovery of cellular immunity was observed until three months after irradiation and the role of cellular immunity to proliferation of leukemic cells after three months was negligible. (author)

Expression of MICA, MICB and NKG2D in human leukemic myelomonocytic and cervical cancer cells

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Mendoza-Rincon Jorge

2011-04-01

Full Text Available Abstract Background Cancer cells are known to secrete the stress molecules MICA and MICB that activate cytotoxicity by lymphocytes and NK cells through their NKG2D receptor as a mechanism of immunological defense. This work was undertaken to evaluate if cancer cells can also express this receptor as a possible mechanisms of depletion of MIC molecules and thus interfere with their immune recognition. Methods Myelomonocytic leukemic (TPH-1 and U-937 and cervical cancer (CALO and INBL cell lines were evaluated by Western Blot, ELISA, flow cytometry and immunocytochemistry to evaluate their capacity to express and secrete MICA and MICB and to be induced to proliferate by these molecules as well as to express their receptor NKG2D. Statistical analysis was performed by two-way ANOVA for time course analysis and Student's t-test for comparison between groups. Values were considered significantly different if p Results THP-1 and U-937 produce and secrete the stress MICA and MICB as shown by Western Blot of lysed cells and by ELISA of their conditioned media. By Western Blot and flow cytometry we found that these cells also express the receptor NKG2D. When THP-1 and U-937 were cultured with recombinant MICA and MICB they exhibited a dose dependent induction for their proliferation. CALO and INBL also produce MICA and MICB and were induced to proliferate by these stress molecules. By Western Blot, flow cytometry and immunocytochemistry we also found that these cells express NKG2D. Conclusions Our novel results that tumor cells can simultaneously secrete MIC molecules and express their receptor, and to be induced for proliferation by these stress molecules, and that tumor epithelial cells can also express the NKG2D receptor that was thought to be exclusive of NK and cytotoxic lymphocytes is discussed as a possible mechanism of immunological escape and of tumor growth induction.

Nanobody Based Dual Specific CARs

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Stijn De Munter

2018-01-01

Full Text Available Recent clinical trials have shown that adoptive chimeric antigen receptor (CAR T cell therapy is a very potent and possibly curative option in the treatment of B cell leukemias and lymphomas. However, targeting a single antigen may not be sufficient, and relapse due to the emergence of antigen negative leukemic cells may occur. A potential strategy to counter the outgrowth of antigen escape variants is to broaden the specificity of the CAR by incorporation of multiple antigen recognition domains in tandem. As a proof of concept, we here describe a bispecific CAR in which the single chain variable fragment (scFv is replaced by a tandem of two single-antibody domains or nanobodies (nanoCAR. High membrane nanoCAR expression levels are observed in retrovirally transduced T cells. NanoCARs specific for CD20 and HER2 induce T cell activation, cytokine production and tumor lysis upon incubation with transgenic Jurkat cells expressing either antigen or both antigens simultaneously. The use of nanobody technology allows for the production of compact CARs with dual specificity and predefined affinity.

Nanobody Based Dual Specific CARs.

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De Munter, Stijn; Ingels, Joline; Goetgeluk, Glenn; Bonte, Sarah; Pille, Melissa; Weening, Karin; Kerre, Tessa; Abken, Hinrich; Vandekerckhove, Bart

2018-01-30

Recent clinical trials have shown that adoptive chimeric antigen receptor (CAR) T cell therapy is a very potent and possibly curative option in the treatment of B cell leukemias and lymphomas. However, targeting a single antigen may not be sufficient, and relapse due to the emergence of antigen negative leukemic cells may occur. A potential strategy to counter the outgrowth of antigen escape variants is to broaden the specificity of the CAR by incorporation of multiple antigen recognition domains in tandem. As a proof of concept, we here describe a bispecific CAR in which the single chain variable fragment (scFv) is replaced by a tandem of two single-antibody domains or nanobodies (nanoCAR). High membrane nanoCAR expression levels are observed in retrovirally transduced T cells. NanoCARs specific for CD20 and HER2 induce T cell activation, cytokine production and tumor lysis upon incubation with transgenic Jurkat cells expressing either antigen or both antigens simultaneously. The use of nanobody technology allows for the production of compact CARs with dual specificity and predefined affinity.

Phenotypic and Functional Alterations of Hematopoietic Stem and Progenitor Cells in an In Vitro Leukemia-Induced Microenvironment

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Jean-Paul Vernot

2017-02-01

Full Text Available An understanding of the cell interactions occurring in the leukemic microenvironment and their functional consequences for the different cell players has therapeutic relevance. By co-culturing mesenchymal stem cells (MSC with the REH acute lymphocytic leukemia (ALL cell line, we have established an in vitro leukemic niche for the functional evaluation of hematopoietic stem/progenitor cells (HSPC, CD34+ cells. We showed that the normal homeostatic control exerted by the MSC over the HSPC is considerably lost in this leukemic microenvironment: HSPC increased their proliferation rate and adhesion to MSC. The adhesion molecules CD54 and CD44 were consequently upregulated in HSPC from the leukemic niche. Consequently, with this adhesive phenotype, HSPC showed less Stromal derived factor-1 (SDF-1-directed migration. Interestingly, multipotency was severely affected with an important reduction in the absolute count and the percentage of primitive progenitor colonies. It was possible to simulate most of these HSPC alterations by incubation of MSC with a REH-conditioned medium, suggesting that REH soluble factors and their effect on MSC are important for the observed changes. Of note, these HSPC alterations were reproduced when primary leukemic cells from an ALL type B (ALL-B patient were used to set up the leukemic niche. These results suggest that a general response is induced in the leukemic niche to the detriment of HSPC function and in favor of leukemic cell support. This in vitro leukemic niche could be a valuable tool for the understanding of the molecular events responsible for HSPC functional failure and a useful scenario for therapeutic evaluation.

Defective immunoregulatory T-cell function in chronic lymphocytic leukemia

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Han, T.; Ozer, H.; Henderson, E.S.; Dadey, B.; Nussbaum-Blumenson, A.; Barcos, M.

1981-01-01

Chronic lymphocytic leukemia (CLL) of B-cell origin results in the malignant proliferation of small immunoglobulin-bearing lymphocytes. There is currently a controversy in the literature regarding both the ability of this leukemic population to differentiate into mature plasma cells, as well as the ability of apparently normal T cells from these patients to regulate allogeneic B-cell differentiation. In the present study we have examined the lymphocytes of CLL patients in various clinical stages of their disease and with different surface phenotypes of their leukemic B-cell population. Our results show that leukemic CLL B cells from all 20 patients (including one patient with a monoclonal IgM paraprotein and another with a monoclonal IgG paraprotein) are incapable of further differentiation even in the absence of suppressor T cells and the presence of helper T lymphocytes. This lack of capacity to differentiate is unaffected by clinical stage, by therapy, or by the phenotype of the malignant population. Since the leukemic B population did not suppress normal allogeneic B-cell differentiation, the maturation deficit is evidently intrinsic to the leukemic clone rather than a result of activity of non-T suppressor cells. T helper function was also variably depressed in the blood of some patients with CLL, and this depression did not correlate with clinical stage, with therapy, or with the degree of lymphocytosis. Dysfunction of radiosensitive T suppressor cells was found to be the most consistent regulatory deficit of CLL T cells. Each of 11 patients whose leukemic cell population was of the μdelta, μα, or μ phenotype had both helper and suppressor cell defects

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.

A model with competition between the cell lines in leukemia under treatment

International Nuclear Information System (INIS)

Halanay, A.; Cândea, D.; Rădulescu, R.

2014-01-01

The evolution of leukemia is modeled with a delay differential equation model of four cell populations: two populations (healthy and leukemic) ) of stem-like cells involving a larger category consisting of proliferating stem and progenitor cells with self-renew capacity and two populations (healthy and leukemic) of mature cells, considering the competition of healthy vs. leukemic cell populations and three types of division that a stem-like cell can exhibit: self-renew, asymmetric division and differentiation. In the model it is assumed that the treatment acts on the proliferation rate of the leukemic stem cells and on the apoptosis of stem and mature cells. The emphasis in this model is on establishing relevant parameters for chronic and acute manifestations of leukemia. Stability of equilibria is investigated and sufficient conditions for local asymptotic stability will be given using a Lyapunov-Krasovskii functional

Quantitative MR imaging of normal and leukemic bone marrow

International Nuclear Information System (INIS)

Hinks, R.S.; Dunlap, H.J.; Poon, P.Y.; Curtis, J.; Henkelman, R.M.

1986-01-01

The authors have developed and tested a protocol that allows extraction of reliable T1 and T2 relaxation times from imaging data. They have used these methods to study in vivo the bone marrow of healthy volunteers and patients with acute leukemia. Examinations were performed at 6.25 MHz using an interleaved ISE/SE sequence to calculate T1 and an eight echo (TE = 25) sequence to calculate T2. The results are summarized as follows: In leukemic patients, T1 = 476 +- 115 msec; in leukemic patients in remission, T1 = 290 +- 31 msec; in healthy volunteers, T1 = 329 +- 32 msec. The T2 values were not significantly different for the three groups (105 +- 10 msec). Work is underway to evaluate whether T1 values of bone marrow may be used to monitor patients in remission and to detect the onset of relapse

Catch me if you can: Leukemia Escape after CD19-Directed T Cell Immunotherapies

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Marco Ruella

2016-01-01

Full Text Available Immunotherapy is the revolution in cancer treatment of this last decade. Among multiple approaches able to harness the power of the immune system against cancer, T cell based immunotherapies represent one of the most successful examples. In particular, biotechnological engineering of protein structures, like the T cell receptor or the immunoglobulins, allowed the generation of synthetic peptides like chimeric antigen receptors and bispecific antibodies that are able to redirect non-tumor specific T cells to recognize and kill leukemic cells. The anti-CD19/CD3 bispecific antibody blinatumomab and anti-CD19 chimeric antigen receptor T cells (CART19 have produced deep responses in patients with relapsed and refractory B-cell acute leukemias. However, although the majority of these patients responds to anti-CD19 immunotherapy, a subset of them still relapses. Interestingly, a novel family of leukemia escape mechanisms has been described, all characterized by the apparent loss of CD19 on the surface of leukemic blasts. This extraordinary finding demonstrates the potent selective pressure of CART19/blinatumomab that drives extreme and specific escape strategies by leukemic blasts. Patients with CD19-negative relapsed leukemia have very poor prognosis and novel approaches to treat and ideally prevent antigen-loss are direly needed. In this review we discuss the incidence, mechanisms and therapeutic approaches for CD19-negative leukemia relapses occuring after CD19-directed T cell immunotherapies and present our future perspective.

Adaptive Immunity to Leukemia Is Inhibited by Cross-Reactive Induced Regulatory T Cells.

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Manlove, Luke S; Berquam-Vrieze, Katherine E; Pauken, Kristen E; Williams, Richard T; Jenkins, Marc K; Farrar, Michael A

2015-10-15

BCR-ABL(+) acute lymphoblastic leukemia patients have transient responses to current therapies. However, the fusion of BCR to ABL generates a potential leukemia-specific Ag that could be a target for immunotherapy. We demonstrate that the immune system can limit BCR-ABL(+) leukemia progression although ultimately this immune response fails. To address how BCR-ABL(+) leukemia escapes immune surveillance, we developed a peptide: MHC class II tetramer that labels endogenous BCR-ABL-specific CD4(+) T cells. Naive mice harbored a small population of BCR-ABL-specific T cells that proliferated modestly upon immunization. The small number of naive BCR-ABL-specific T cells was due to negative selection in the thymus, which depleted BCR-ABL-specific T cells. Consistent with this observation, we saw that BCR-ABL-specific T cells were cross-reactive with an endogenous peptide derived from ABL. Despite this cross-reactivity, the remaining population of BCR-ABL reactive T cells proliferated upon immunization with the BCR-ABL fusion peptide and adjuvant. In response to BCR-ABL(+) leukemia, BCR-ABL-specific T cells proliferated and converted into regulatory T (Treg) cells, a process that was dependent on cross-reactivity with self-antigen, TGF-β1, and MHC class II Ag presentation by leukemic cells. Treg cells were critical for leukemia progression in C57BL/6 mice, as transient Treg cell ablation led to extended survival of leukemic mice. Thus, BCR-ABL(+) leukemia actively suppresses antileukemia immune responses by converting cross-reactive leukemia-specific T cells into Treg cells. Copyright © 2015 by The American Association of Immunologists, Inc.

Clinical impact of leukemic blast heterogeneity at diagnosis in cytogenetic intermediate-risk acute myeloid leukemia

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Hoffmann, Marianne Hutchings; Klausen, Tobias Wirenfeldt; Boegsted, Martin

2012-01-01

Individual cellular heterogeneity within the acute myeloid leukemia (AML) bone marrow samples can be observed by multi parametric flow cytometry analysis (MFC) indicating that immunophenotypic screening for leukemic blast subsets may have prognostic impact.......Individual cellular heterogeneity within the acute myeloid leukemia (AML) bone marrow samples can be observed by multi parametric flow cytometry analysis (MFC) indicating that immunophenotypic screening for leukemic blast subsets may have prognostic impact....

Unveiling the role of PAK2 in CD44 mediated inhibition of proliferation, differentiation and apoptosis in AML cells

KAUST Repository

Aldehaiman, Mansour M.

2018-01-01

the success of the differentiation agent, All-trans retinoic acid (ATRA), in the treatment of acute promyelocytic leukemia (APL), much effort has gone into trying to find agents that are able to differentiate AML cells and specifically the leukemic stem cell

A micro-Raman spectroscopic investigation of leukemic U-937 cells treated with Crotalaria agatiflora Schweinf and the isolated compound madurensine

Science.gov (United States)

le Roux, Karlien; Prinsloo, Linda C.; Hussein, Ahmed A.; Lall, Namrita

In South Africa traditional medicine plays an important role in primary health care and therefore it is very important that the medicinal use of plants is scientifically tested for toxicity and effectiveness. It was established that the ethanolic extract of the leaves of Crotalaria agatiflora, as well as the isolated compound madurensine, is moderately toxic against leukemic U-937 cells. Light microscopic investigations indicated that symptoms of cell death are induced during treatments, but flow cytometry analysis of treated cells, using annexin-V and propidium iodide, showed that apoptosis and necrosis are insignificantly induced. The Raman results suggested that protein extraction and DNA melting occur in the cells during treatment with the ethanolic extracts (IC50 value 73.9 μg/mL), drastically changing the molecular content of the cells. In contrast, treatment with madurensine (IC50 value 136.5 μg/mL), an isolated pyrrolizidine alkaloid from the ethanolic extract of the leaves, did not have the same effect. The results are also compared to that of cells treated with actinomycin D, a compound known to induce apoptosis. The investigation showed that micro-Raman spectroscopy has great promise to be used for initial screening of samples to determine the effects of different treatments on cancerous cell lines together with conventional methods. The results highlight the fact that for many natural products used for medicinal purposes, the therapeutic effect of the crude plant extract tends to be significantly more effective than the particular action of its individual constituents.

Predicting radiation effects on the development of leukemic stem cells based on studies of leukemias induced by high- and low-dose-rate radiation

International Nuclear Information System (INIS)

Hirouchi, Tokuhisa

2012-01-01

One of the most important causes of radiation-induced cancers, particularly leukemia, is gene mutations resulting from single and double strand breaks in the DNA. Tanaka et al. (2003) reported life shortening in specific pathogen free male and female B6C3F1 mice continuously exposed to γ rays at a low dose rate of 20 mGy/22 h/d for 400 days from 8 weeks of age. Early death due to cancer, mostly malignant lymphomas, was observed in both sexes. A significant increase in the incidence of myeloid leukemia, resulting in early death, was also reported in males. It is expected however, that at 20 mGy/22 h/d, which is equivalent to a dose of 15 μGy/min, DNA strand breaks induced in these cells are repaired soon after they occur. Murine leukemias induced by high-dose-rate radiation were also found in males, and 80% of the mice with leukemia had hemizygous deletions in chromosome 2 around the PU.1 gene and they appeared to be derived from DNA strand breaks. Majority of these leukemia showing hemizygous deletions in chromosome 2 revealed point mutations in the remaining alleles resulting in PU.1 inactivation, which was reported to be related to leukemogenesis. These point mutations are assumed to be independent of DNA strand breaks that occur immediately after irradiation, as they appear at later time after irradiation. This review discusses the effect of radiation-induced DNA strand breaks and also mutagenesis induced independently of DNA strand breaks in hematopoietic cells contributing to the development of the first leukemic stem cell. (author)

Chromosomal Aberrations Associated with Clonal Evolution and Leukemic Transformation in Fanconi Anemia: Clinical and Biological Implications

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Stefan Meyer

2012-01-01

Full Text Available Fanconi anaemia (FA is an inherited disease with congenital and developmental abnormalities, bone marrow failure, and extreme risk of leukemic transformation. Bone marrow surveillance is an important part of the clinical management of FA and often reveals cytogenetic aberrations. Here, we review bone marrow findings in FA and discuss the clinical and biological implications of chromosomal aberrations associated with leukemic transformation.

Correlation of chromosome patterns in human leukemic cells with exposure to chemicals and/or radiation. Progress report, January 1, 1981-December 31, 1981

International Nuclear Information System (INIS)

Rowley, J.D.

1981-08-01

The overall aim is to determine whether there is a relationship between exposure to radiation, environmental pollutants, and/or genetic background and the development of ANLL or other hematologic malignancies. I will try to define the factors that influence the development of ANLL as a second malignancy in patients who have been exposed to large doses of radiotherapy and/or chemotherapeutic agents. Two long-term goals are (1) to identify the genes that are located at the sites of consistent translocations, and then to determine the alterations in gene function that are associated with these translocations and (2) to establish the baseline frequency of various chromosome changes (mutations) in myeloid cells and then to analyze the influence of various types of environmental exposure or medical treatment on this baseline mutation rate. Ultimately, it may be possible to determine the extent of mutagenic exposure in various populations through an analysis of the leukemic cells of that populations

Colloidal silver nanoparticles improve anti-leukemic drug efficacy via amplification of oxidative stress.

Science.gov (United States)

Guo, Dawei; Zhang, Junren; Huang, Zhihai; Jiang, Shanxiang; Gu, Ning

2015-02-01

Recently, increased reactive oxygen species (ROS) levels and altered redox status in cancer cells have become a novel therapeutic strategy to improve cancer selectivity over normal cells. It has been known that silver nanoparticles (AgNPs) display anti-leukemic activity via ROS overproduction. Hence, we hypothesized that AgNPs could improve therapeutic efficacy of ROS-generating agents against leukemia cells. In the current study, N-(4-hydroxyphenyl)retinamide (4-HPR), a synthetic retinoid, was used as a drug model of ROS induction to investigate its synergistic effect with AgNPs. The data exhibited that AgNPs with uniform size prepared by an electrochemical method could localize in the lysosomes, mitochondria and cytoplasm of SHI-1 cells. More importantly, AgNPs together with 4-HPR could exhibit more cytotoxicity and apoptosis via overproduction of ROS in comparison with that alone. Taken together, these results reveal that AgNPs combined with ROS-generating drugs could potentially enhance therapeutic efficacy against leukemia cells, thereby providing a novel strategy for AgNPs in leukemia therapy. Copyright © 2015. Published by Elsevier B.V.

Heterogeneity of clonogenic cells in acute myeloblastic leukemia.

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Sabbath, K D; Ball, E D; Larcom, P; Davis, R B; Griffin, J D

1985-02-01

The expression of differentiation-associated surface antigens by the clonogenic leukemic cells from 20 patients with acute myeloblastic leukemia (AML) was studied with a panel of seven cytotoxic monoclonal antibodies (anti-Ia, -MY9, -PM-81, -AML-2-23, -Mol, -Mo2, and -MY3). The surface antigen phenotypes of the clonogenic cells were compared with the phenotypes of the whole leukemic cell population, and with the phenotypes of normal hematopoietic progenitor cells. In each case the clonogenic leukemic cells were found within a distinct subpopulation that was less "differentiated" than the total cell population. Clonogenic leukemic cells from different patients could be divided into three phenotype groups. In the first group (7 of 20 cases), the clonogenic cells expressed surface antigens characteristic of the normal multipotent colony-forming cell (Ia, MY9). These cases tended to have "undifferentiated" (FAB M1) morphology, and the total cell population generally lacked expression of "late" monocyte antigens such as MY3 and Mo2. A second group (seven cases) of clonogenic cells expressed surface antigens characteristic of an "early" (day 14) colony-forming unit granulocyte-monocyte (CFU-GM), and a third group (six cases) was characteristic of a "late" (day 7) CFU-GM. The cases in these latter two groups tended to have myelomonocytic (FAB M4) morphology and to express monocyte surface antigens. These results suggest that the clonogenic cells are a distinct subpopulation in all cases of AML, and may be derived from normal hematopoietic progenitor cells at multiple points in the differentiation pathway. The results further support the possibility that selected monoclonal antibodies have the potential to purge leukemic clonogenic cells from bone marrow in some AML patients without eliminating critical normal progenitor cells.

Sporadic on/off switching of HTLV-1 Tax expression is crucial to maintain the whole population of virus-induced leukemic cells.

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Mahgoub, Mohamed; Yasunaga, Jun-Ichirou; Iwami, Shingo; Nakaoka, Shinji; Koizumi, Yoshiki; Shimura, Kazuya; Matsuoka, Masao

2018-02-06

Viruses causing chronic infection artfully manipulate infected cells to enable viral persistence in vivo under the pressure of immunity. Human T-cell leukemia virus type 1 (HTLV-1) establishes persistent infection mainly in CD4+ T cells in vivo and induces leukemia in this subset. HTLV-1-encoded Tax is a critical transactivator of viral replication and a potent oncoprotein, but its significance in pathogenesis remains obscure due to its very low level of expression in vivo. Here, we show that Tax is expressed in a minor fraction of leukemic cells at any given time, and importantly, its expression spontaneously switches between on and off states. Live cell imaging revealed that the average duration of one episode of Tax expression is ∼19 hours. Knockdown of Tax rapidly induced apoptosis in most cells, indicating that Tax is critical for maintaining the population, even if its short-term expression is limited to a small subpopulation. Single-cell analysis and computational simulation suggest that transient Tax expression triggers antiapoptotic machinery, and this effect continues even after Tax expression is diminished; this activation of the antiapoptotic machinery is the critical event for maintaining the population. In addition, Tax is induced by various cytotoxic stresses and also promotes HTLV-1 replication. Thus, it seems that Tax protects infected cells from apoptosis and increases the chance of viral transmission at a critical moment. Keeping the expression of Tax minimal but inducible on demand is, therefore, a fundamental strategy of HTLV-1 to promote persistent infection and leukemogenesis. Copyright © 2018 the Author(s). Published by PNAS.

Anti-ATLA (antibody to adult T-cell leukemia-lymphoma virus-associated antigen)-negative adult T-cell leukemia-lymphoma.

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Shimoyama, M; Minato, K; Tobinai, K; Nagai, M; Setoya, T; Watanabe, S; Hoshino, H; Miwa, M; Nagoshi, H; Ichiki, N; Fukushima, N; Sugiura, K; Funaki, N

1983-01-01

Five cases of adult T-cell leukemia-lymphoma (ATL) having typical clinicohematologic and morphologic features but negative for anti-ATLA [antibody to ATL virus (ATLV)-associated antigen (ATLA)] are presented. Some differences in immunologic, epidemiologic, and serologic data between anti-ATLA-positive and -negative ATLs are also described. Expression of ATLA in early primary cultured leukemic cells was found to be negative in three patients tested (Cases 1, 2 and 4), however, a long-term cultured cell line, ATL-6A, derived from peripheral blood leukemia cells from Case 1, was found to express ATLA. Mother of Case 1 and a daughter of Case 2 were anti-ATLA negative. These results indicate that ATLV was involved in certain anti-ATLA-negative ATL patients, at least in Case 1, and that the patient had no detectable immune response against ATLV and ATLA. However, in other cases in which no ATLA reactivity of serum and no ATLA expression in cultured leukemic cells were observed, another possibility such as activation of an unknown cellular oncogene specific for ATL without ATLV involvement may be considered. In order to prove these possibilities definitely, it is necessary to elucidate whether or not proviral DNA of ATLV is integrated into chromosomal DNA of ATL cells and to find a cellular oncogene specific for ATL in the future.

Inhibition of c-Myc overcomes cytotoxic drug resistance in acute myeloid leukemia cells by promoting differentiation.

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Xiao-Na Pan

Full Text Available Nowadays, drug resistance still represents a major obstacle to successful acute myeloid leukemia (AML treatment and the underlying mechanism is not fully elucidated. Here, we found that high expression of c-Myc was one of the cytogenetic characteristics in the drug-resistant leukemic cells. c-Myc over-expression in leukemic cells induced resistance to chemotherapeutic drugs, enhanced colony formation capacity and inhibited cell differentiation induced by all-trans retinoic acid (ATRA. Meanwhile, inhibition of c-Myc by shRNA or specific c-Myc inhibitor 10058-F4 rescued the sensitivity to cytotoxic drugs, restrained the colony formation ability and promoted differentiation. RT-PCR and western blotting analysis showed that down-regulation of C/EBPβ contributed to the poor differentiation state of leukemic cells induced by c-Myc over-expression. Importantly, over-expression of C/EBPβ could reverse c-Myc induced drug resistance. In primary AML cells, the c-Myc expression was negatively correlated with C/EBPβ. 10058-F4, displayed anti-proliferative activity and increased cellular differentiation with up-regulation of C/EBPβ in primary AML cells. Thus, our study indicated that c-Myc could be a novel target to overcome drug resistance, providing a new approach in AML therapy.

Activation of store – operated Ca(2+ entry in cisplatin resistant leukemic cells after treatment with photoexcited fullerene C(60 and cisplatin

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D. V. Franskevych

2018-04-01

Full Text Available Ca2+-regulating system in cancer cells is suggested to be remodulated particularly by reduced store-operated Ca2+ entry (SOCE through plasma membrane in order to maintain moderately reduced cytosolic Ca2+ concentration and to avoid apoptosis. The endoplasmic reticulum (ER Ca2+ pool content and the size of SOCE in leukemic wild type (L1210 and resistant to cisplatin (L1210R cells in control, after treatment with either cisplatin (1 µg/ml or photoexcited fulleren C60 (10-5 M alone, or their combination were estimated with the use of Indo-1 AM. The SOCE in resistant to cisplatin L1210R cells was found to be lower than in the wild-type cells. After treatment with cisplatin the decrease of thapsigargin (TG-sensitive ER Ca2+ pool with no significant increase of SOCE was observed in L1210 cells, while no changes were detected in L1210R cells. Photoexcitation of intracellular accumulated fullerene C60 in the visible range of spectrum (410-700 nm was accompanied by increase of SOCE not only in sensitive, but in resistant cells as well. In resistant L1210R cells treated with photoexcited C60 essential effect of cisplatin on Ca2+ homeostasis became obvious: the size of SOCE proved to be higher than after treatment with photoexcited C60 alone. The data obtained allow suggesting­ the influence of photoexcited C60 not only on Ca2+-regulating system, but on those involved in controlling cisplatin entry into drug resistant cancer cells.

Paraptosis cell death induction by the thiamine analog benfotiamine in leukemia cells.

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Naomi Sugimori

Full Text Available Benfotiamine is a synthetic thiamine analogue that stimulates transketolase, a cellular enzyme essential for glucose metabolism. Currently, benfotiamine is used to treat diabetic neuropathy. We recently reported that oral benfotiamine induced a temporary but remarkable recovery from acute myeloid leukemia in an elderly patient who was ineligible for standard chemotherapy due to dementia and renal failure. In the present study we present evidences that benfotiamine possess antitumor activity against leukemia cells. In a panel of nine myeloid leukemia cell lines benfotiamine impaired the viability of HL-60, NB4, K562 and KG1 cells and also inhibited the growing of primary leukemic blasts. The antitumor activity of benfotiamine is not mediated by apoptosis, necrosis or autophagy, but rather occurs though paraptosis cell death induction. Mechanistic studies revealed that benfotiamine inhibited the activity of constitutively active ERK1/2 and concomitantly increased the phosphorylation of JNK1/2 kinase in leukemic cells. In addition, benfotiamine induced the down regulation of the cell cycle regulator CDK3 which resulted in G1 cell cycle arrest in the sensitive leukemic cells. Moreover, combination index studies showed that benfotiamine enhanced the antiproliferative activities of cytarabine against leukemia cells. These findings suggest that benfotiamine has antitumor therapeutic potential.

Paraptosis cell death induction by the thiamine analog benfotiamine in leukemia cells.

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Sugimori, Naomi; Espinoza, J Luis; Trung, Ly Quoc; Takami, Akiyoshi; Kondo, Yukio; An, Dao Thi; Sasaki, Motoko; Wakayama, Tomohiko; Nakao, Shinji

2015-01-01

Benfotiamine is a synthetic thiamine analogue that stimulates transketolase, a cellular enzyme essential for glucose metabolism. Currently, benfotiamine is used to treat diabetic neuropathy. We recently reported that oral benfotiamine induced a temporary but remarkable recovery from acute myeloid leukemia in an elderly patient who was ineligible for standard chemotherapy due to dementia and renal failure. In the present study we present evidences that benfotiamine possess antitumor activity against leukemia cells. In a panel of nine myeloid leukemia cell lines benfotiamine impaired the viability of HL-60, NB4, K562 and KG1 cells and also inhibited the growing of primary leukemic blasts. The antitumor activity of benfotiamine is not mediated by apoptosis, necrosis or autophagy, but rather occurs though paraptosis cell death induction. Mechanistic studies revealed that benfotiamine inhibited the activity of constitutively active ERK1/2 and concomitantly increased the phosphorylation of JNK1/2 kinase in leukemic cells. In addition, benfotiamine induced the down regulation of the cell cycle regulator CDK3 which resulted in G1 cell cycle arrest in the sensitive leukemic cells. Moreover, combination index studies showed that benfotiamine enhanced the antiproliferative activities of cytarabine against leukemia cells. These findings suggest that benfotiamine has antitumor therapeutic potential.

Heterogeneity of clonogenic cells in acute myeloblastic leukemia.

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Sabbath, K D; Ball, E D; Larcom, P; Davis, R B; Griffin, J D

1985-01-01

The expression of differentiation-associated surface antigens by the clonogenic leukemic cells from 20 patients with acute myeloblastic leukemia (AML) was studied with a panel of seven cytotoxic monoclonal antibodies (anti-Ia, -MY9, -PM-81, -AML-2-23, -Mol, -Mo2, and -MY3). The surface antigen phenotypes of the clonogenic cells were compared with the phenotypes of the whole leukemic cell population, and with the phenotypes of normal hematopoietic progenitor cells. In each case the clonogenic ...

JS-K, an arylating nitric oxide (NO) donor, has synergistic anti-leukemic activity with cytarabine (ARA-C).

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Shami, Paul J; Maciag, Anna E; Eddington, Jordan K; Udupi, Vidya; Kosak, Ken M; Saavedra, Joseph E; Keefer, Larry K

2009-11-01

We have designed prodrugs that release nitric oxide (NO) on metabolism by glutathione S-transferases (GST). This design exploits the upregulation of GST in acute myeloid leukemia (AML) cells. O(2)-(2,4-dinitrophenyl) 1-[(4-ethoxycarbonyl)piperazin-1-yl]diazen-1-ium-1,2-diolate (JS-K, a member of this class) has potent anti-leukemic activity. HL-60 myeloid leukemia cells were used for in vitro studies of the combination of JS-K with daunorubicin (DAUNO), cytarabine (ARA-C) or etoposide (ETOP) using the median effect method to determine synergistic, antagonistic, or additive effects. Combinations of JS-K added simultaneously, 2h before or 2h after the other compounds were used. JS-K and DAUNO were antagonistic in all three drug sequences. JS-K and ETOP were also antagonistic but to a lesser degree. JS-K and ARA-C showed strong synergy. The combination index at the 50% fraction affected was 0.37+/-0.23, 0.24+/-0.27, and 0.15+/-0.11 for simultaneous, JS-K first and ARA-C first additions, respectively. JS-K by itself induced DNA strand breaks at relatively high concentrations. However, at submicromolar concentrations, it significantly augmented ARA-C-induced DNA strand breaks. NMR spectroscopy revealed no evidence of chemical interaction between JS-K and the other chemotherapeutic agents. We conclude that ARA-C and JS-K have synergistic anti-leukemic activity and warrant further exploration in combination.

Bortezomib as a new therapeutic approach for blastic plasmacytoid dendritic cell neoplasm.

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Philippe, Laure; Ceroi, Adam; Bôle-Richard, Elodie; Jenvrin, Alizée; Biichle, Sabeha; Perrin, Sophie; Limat, Samuel; Bonnefoy, Francis; Deconinck, Eric; Saas, Philippe; Garnache-Ottou, Francine; Angelot-Delettre, Fanny

2017-11-01

Blastic plasmacytoid dendritic cell neoplasm is an aggressive hematologic malignancy with a poor prognosis. No consensus regarding optimal treatment modalities is currently available. Targeting the nuclear factor-kappa B pathway is considered a promising approach since blastic plasmacytoid dendritic cell neoplasm has been reported to exhibit constitutive activation of this pathway. Moreover, nuclear factor-kappa B inhibition in blastic plasmacytoid dendritic cell neoplasm cell lines, achieved using either an experimental specific inhibitor JSH23 or the clinical drug bortezomib, interferes in vitro with leukemic cell proliferation and survival. Here we extended these data by showing that primary blastic plasmacytoid dendritic cell neoplasm cells from seven patients were sensitive to bortezomib-induced cell death. We confirmed that bortezomib efficiently inhibits the phosphorylation of the RelA nuclear factor-kappa B subunit in blastic plasmacytoid dendritic cell neoplasm cell lines and primary cells from patients in vitro and in vivo in a mouse model. We then demonstrated that bortezomib can be associated with other drugs used in different chemotherapy regimens to improve its impact on leukemic cell death. Indeed, when primary blastic plasmacytoid dendritic cell neoplasm cells from a patient were grafted into mice, bortezomib treatment significantly increased the animals' survival, and was associated with a significant decrease of circulating leukemic cells and RelA nuclear factor-kappa B subunit expression. Overall, our results provide a rationale for the use of bortezomib in combination with other chemotherapy for the treatment of patients with blastic plasmacytoid dendritic cell neoplasm. Based on our data, a prospective clinical trial combining proteasome inhibitor with classical drugs could be envisaged. Copyright© Ferrata Storti Foundation.

Leu-9 (CD 7) positivity in acute leukemias: a marker of T-cell lineage?

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Ben-Ezra, J; Winberg, C D; Wu, A; Rappaport, H

1987-01-01

Monoclonal antibody Leu-9 (CD 7) has been reported to be a sensitive and specific marker for T-cell lineage in leukemic processes, since it is positive in patients whose leukemic cells fail to express other T-cell antigens. To test whether Leu-9 is indeed specific for T-cell leukemias, we examined in detail 10 cases of acute leukemia in which reactions were positive for Leu-9 and negative for other T-cell-associated markers including T-11, Leu-1, T-3, and E-rosettes. Morphologically and cytochemically, 2 of these 10 leukemias were classified as lymphoblastic, 4 as myeloblastic, 2 as monoblastic, 1 as megakaryoblastic, and 1 as undifferentiated. The case of acute megakaryoblastic leukemia is the first reported case to be Leu-9 positive. None of the 10 were TdT positive. Of six cases (two monoblastic, one lymphoblastic, one myeloblastic, one megakaryoblastic, and one undifferentiated) in which we evaluated for DNA gene rearrangements, only one, a peroxidase-positive leukemia, showed a novel band on study of the T-cell-receptor beta-chain gene. We therefore conclude that Leu-9 is not a specific marker to T-cell lineage and that, in the absence of other supporting data, Leu-9 positivity should not be used as the sole basis of classifying an acute leukemia as being T-cell derived.

Anti-leukemic effect of a synthetic compound, (±) trans-dihydronarciclasine (HYU-01) via cell-cycle arrest and apoptosis in acute myeloid leukemia.

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Kim, Seo Ju; Park, Hyun Ki; Kim, Ju Young; Yoon, Jin Sun; Kim, Eun Shil; Cho, Cheon-Gyu; Kim, Byoung Kook; Park, Byeong Bae; Lee, Young Yiul

2012-10-01

(±) trans-Dihydronarciclasine, isolated from Chinese medicinal plant Zephyranthes candida, has been shown to possess quite potent anti-tumoral effect against selected human cancer cell lines. However, little is known about the anti-tumoral effect of (±) trans-dihydronarciclasine in acute myeloid leukemia (AML). This study was performed to investigate the effect of a novel synthetic (±) trans-dihydronarciclasine (code name; HYU-01) in AML. The HYU-01 inhibited the proliferation of various AML cell lines including HL-60 as well as primary leukemic blasts in a dose-dependent manner. To investigate the mechanism of the anti-proliferative effect of HYU-01, cell-cycle analysis was attempted in HL-60 cells, resulting in G1 arrest. The expression levels of CDK2, CDK4, CDK6, cyclin E, and cyclin A were decreased in a time-dependent manner. In addition, HYU-01 up-regulated the expression of the p27, and markedly enhanced the binding of p27 with CDK2, 4, and 6, ultimately resulting in the decrease of their kinase activities. Furthermore, HYU-01 induced the apoptosis through the induction of proapoptotic molecules and reduction of antiapoptotic molecules in association with the activation of caspase-3, -8, and -9. These results suggest that HYU-01 may inhibit the proliferation of HL-60 cells, via apoptosis, as well as G1 block in association with the induction of p27. © 2012 The Authors APMIS © 2012 APMIS.

Alternative Splice Variants Modulates Dominant-Negative Function of Helios in T-Cell Leukemia.

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Shaorong Zhao

Full Text Available The molecular defects which lead to multistep incidences of human T-cell leukemia have yet to be identified. The DNA-binding protein Helios (known as IKZF2, a member of the Ikaros family of Krüppel-like zinc-finger proteins, functions pivotally in T-cell differentiation and activation. In this study, we identify three novel short Helios splice variants which are T-cell leukemic specific, and demonstrate their dominant-negative function. We then test the cellular localization of distinct Helios isoforms, as well as their capability to form heterodimer with Ikaros, and the association with complexes comprising histone deacetylase (HDAC. In addition, the ectopic expression of T-cell leukemic Helios isoforms interferes with T-cell proliferation and apoptosis. The gene expression profiling and pathway analysis indicated the enrichment of signaling pathways essential for gene expression, translation, cell cycle checkpoint, and response to DNA damage stimulus. These data indicate the molecular function of Helios to be involved in the leukemogenesis and phenotype of T-cell leukemia, and also reveal Helios deregulation as a novel marker for T-cell leukemia.

Vaccination of B-CLL patients with autologous dendritic cells can change the frequency of leukemia antigen-specific CD8+ T cells as well as CD4+CD25+FoxP3+ regulatory T cells toward an antileukemia response.

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Hus, I; Schmitt, M; Tabarkiewicz, J; Radej, S; Wojas, K; Bojarska-Junak, A; Schmitt, A; Giannopoulos, K; Dmoszyńska, A; Roliński, J

2008-05-01

Recently, we described that vaccination with allogeneic dendritic cells (DCs) pulsed with tumor cell lysate generated specific CD8+ T cell response in patients with B-cell chronic lymphocytic leukemia (B-CLL). In the present study, the potential of autologous DCs pulsed ex vivo with tumor cell lysates to stimulate antitumor immunity in patients with B-CLL in early stages was evaluated. Twelve patients at clinical stage 0-2 as per Rai were vaccinated intradermally up to eight times with a mean number of 7.4 x 10(6) DCs pulsed with B-CLL cell lysate. We observed a decrease of peripheral blood leukocytes and CD19+/CD5+ leukemic cells in five patients, three patients showed a stable disease and four patients progressed despite DC vaccination. A significant increase of specific cytotoxic CD8+ T lymphocytes against the leukemia-associated antigens RHAMM or fibromodulin was detected in four patients after DC vaccination. In patients with a clinical response, an increase of interleukin 12 (IL-12) serum levels and a decrease of the frequency of CD4+CD25(+)FOXP3+ T regulatory cells were observed. Taken together, the study demonstrated that vaccination with autologous DC in CLL patients is feasible and safe. Immunological and to some extend hematological responses could be noted, justifying further investigation on this immunotherapeutical approach.

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.

Novel CD7-specific nanobody-based immunotoxins potently enhanced apoptosis of CD7-positive malignant cells.

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Tang, Jinle; Li, Jialu; Zhu, Xuejun; Yu, Yuan; Chen, Dan; Yuan, Lei; Gu, Zhenyang; Zhang, Xingding; Qi, Lin; Gong, Zhishu; Jiang, Pengjun; Yu, Juhua; Meng, Huimin; An, Gangli; Zheng, Huyong; Yang, Lin

2016-06-07

Various CD7-targeting immunotoxins have been tested for its potential in treating CD7+ malignant patients but none of those immunotoxins was approved clinically because of lacking enough efficacy and safety. Here we successfully constructed the monovalent and bivalent CD7 nanobody-based immunotoxins PG001 and PG002, both conjugated with a truncated derivative of Pseudomonas exotoxin A respectively. The prokaryotic system expressed immunotoxins not only maintained their binding specificity for CD7-positive cells with a Kd of 16.74 nM and 3.6 nM for PG001 and PG002 respectively, but also efficiently promoted antigen-restricted apoptosis of the CD7-positive leukemia cell lines Jurkat and CEM, and primary T-cell acute lymphoblastic leukemia (T-ALL) and acute myeloid leukemia (AML) cells with an in vitro cytotoxic activity (EC50) in the range of 23-30 pM for PG002. In NOD/SCID mice transplanted with CEM cells, PG001 and PG002 prevented engraftment of the cells and markedly prolonged mouse survival. Owing to the efficient antigen-restricted anti-leukemic activity of PG002, this CD7 nanobody-based immunotoxin exhibited a superior anti-CD7 positive malignancies activity than previously reported immunotoxins, and may represent a promising therapeutic strategy in treating CD7-positive leukemia and lymphoma, which still remain a significant clinical challenge.

The effect of extracorporeal photopheresis alone or in combination therapy on circulating CD4+Foxp3+CD25- T-cells in patients with leukemic cutaneous T-cell lymphoma

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Shiue, Lisa H.; Couturier, Jacob; Lewis, Dorothy E.; Wei, Caimiao; Ni, Xiao; Duvic, Madeleine

2015-01-01

Purpose Extracorporeal photopheresis (ECP) alone or in combination therapy is effective for treatment of leukemic cutaneous T-cell lymphoma (L-CTCL), but its mechanism(s) of action remain unclear. This study was designed to investigate the effect of ECP on regulatory T-cell and CD8+ T-cells in L-CTCL patients. Experimental Design Peripheral blood from 18 L-CTCL patients at baseline, Day 2, 1-month, 3-month, and 6-month post-ECP therapy were analyzed by flow cytometry for CD4+CD25+/high, CD4+Foxp3+CD25+/-, CD3+CD8+, CD3+CD8+CD69+, and CD3+CD8+IFN-γ+ T-cells. Clinical responses were assessed and correlated with changes in these T-cell subsets. Results Twelve of 18 patients achieved clinical responses. The average baseline number of CD4+CD25+/high T-cells of PBMCs in L-CTCL patients was normal (2.2%), but increased at 6-month post-therapy (4.3%, p<0.01). The average baseline number of CD4+Foxp3+ T-cells out of CD4+ T-cells in 9 evaluable patients was high (66.8±13.7%), mostly CD25 negative. The levels of CD4+Foxp3+ T cells in responders were higher (n=6, 93.1±5.7%) than non-responders (n=3, 14.2±16.0%, p<0.01), and they declined in parallel with malignant T-cells. The numbers of CD3+CD8+CD69+ and CD3+CD8+ IFN-γ+ T-cells increased at 3-month post-therapy in 5 of 6 patients studied. Conclusions ECP alone or in combination therapy might be effective in L-CTCL patients whose malignant T-cells have a CD4+Foxp3+CD25- phenotype. PMID:25772268

Aberrant Expression of CD19 and CD43 in a Patient With Therapy-Related Acute Myeloid Leukemia and a History of Mantle Cell Lymphoma

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Yen-Chuan Hsieh

2009-07-01

Full Text Available Mantle cell lymphoma (MCL is an aggressive B cell lymphoma with frequent involvement of the gastrointestinal tract and peripheral blood (PB. In addition to the B cell markers, the neoplastic cells express CD5 and CD43. In patients with a prior history of MCL with PB involvement, the appearance of leukemic cells after chemotherapy usually heralds a relapse, particularly if the leukemic cells express B cell markers and CD43. We report a patient with MCL who presented with multiple lymphomatous polyposis of the intestine. The staging procedures revealed the involvement of lymph nodes, bone marrow and PB. Three years after chemotherapy, thrombocytopenia with the appearance of rare leukemic cells in the PB was noted. Leukemic cells obtained from bone marrow aspirate expressed CD19 and CD43, suggesting a relapse. Detailed cytomorphological and immunophenotypic studies unveiled the myeloid nature of these leukemic cells, and a diagnosis of therapy-related acute myeloid leukemia was made. This case illustrates the importance of morphologic examination and performing a complete antibody panel in the diagnosis of a suspected relapse in patients with a prior history of lymphoma.

A leukemic double-hit follicular lymphoma associated with a complex variant translocation, t(8;14;18)(q24;q32;q21), involving BCL2, MYC, and IGH.

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Minakata, Daisuke; Sato, Kazuya; Ikeda, Takashi; Toda, Yumiko; Ito, Shoko; Mashima, Kiyomi; Umino, Kento; Nakano, Hirofumi; Yamasaki, Ryoko; Morita, Kaoru; Kawasaki, Yasufumi; Sugimoto, Miyuki; Yamamoto, Chihiro; Ashizawa, Masahiro; Hatano, Kaoru; Oh, Iekuni; Fujiwara, Shin-Ichiro; Ohmine, Ken; Kawata, Hirotoshi; Muroi, Kazuo; Miura, Ikuo; Kanda, Yoshinobu

2018-01-01

Double-hit lymphoma (DHL) is defined as lymphoma with concurrent BCL2 and MYC translocations. While the most common histological subtype of DHL is diffuse large B-cell lymphoma, the present patient had leukemic follicular lymphoma (FL). A 52-year-old man was admitted to our hospital due to general fatigue and cervical and inguinal lymph node swelling. The patient was leukemic and the pathological diagnosis of the inguinal lymph node was FL grade 1. Chromosomal analysis revealed a complex karyotype including a rare three-way translocation t(8;14;18)(q24;q32;q21) involving the BCL2, MYC, and IGH genes. Based on a combination of fluorescence in situ hybridization (FISH), using BCL2, MYC and IGH, and spectral karyotyping (SKY), the karyotype was interpreted as being the result of a multistep mechanism in which the precursor B-cell gained t(14;18) in the bone marrow and acquired a translocation between der(14)t(14;18) and chromosome 8 in the germinal center, resulting in t(8;14;18). The pathological diagnosis was consistently FL, not only at presentation but even after a second relapse. The patient responded well to standard chemotherapies but relapsed after a short remission. This patient is a unique case of leukemic DH-FL with t(8;14;18) that remained in FL even at a second relapse. Copyright © 2017 Elsevier Inc. All rights reserved.

Targeted immunotherapy in acute myeloblastic leukemia: from animals to humans.

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Robin, Marie; Schlageter, Marie-Hélène; Chomienne, Christine; Padua, Rose-Ann

2005-10-01

Immunity against acute myeloid leukemia (AML) is demonstrated in humans by the graft-versus-leukemia effect in allogeneic hematopoietic stem cell transplantation. Specific leukemic antigens have progressively been discovered and circulating specific T lymphocytes against Wilms tumor antigen, proteinase peptide or fusion-proteins produced from aberrant oncogenic chromosomal translocations have been detected in leukemic patients. However, due to the fact that leukemic blasts develop various escape mechanisms, antileukemic specific immunity is not able to control leukemic cell proliferation. The aim of immunotherapy is to overcome tolerance and boost immunity to elicit an efficient immune response against leukemia. We review different immunotherapy strategies tested in preclinical animal models of AML and the human trials that spurred from encouraging results obtained in animal models, demonstrate the feasibility of immunotherapy in AML patients.

MicroRNA expression changes during human leukemic HL-60 cell differentiation induced by 4-hydroxynonenal, a product of lipid peroxidation.

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Pizzimenti, Stefania; Ferracin, Manuela; Sabbioni, Silvia; Toaldo, Cristina; Pettazzoni, Piergiorgio; Dianzani, Mario Umberto; Negrini, Massimo; Barrera, Giuseppina

2009-01-15

4-Hydroxynonenal (HNE) is one of several lipid oxidation products that may have an impact on human pathophysiology. It is an important second messenger involved in the regulation of various cellular processes and exhibits antiproliferative and differentiative properties in various tumor cell lines. The mechanisms by which HNE affects cell growth and differentiation are only partially clarified. Because microRNAs (miRNAs) have the ability to regulate several cellular processes, we hypothesized that HNE, in addition to other mechanisms, could affect miRNA expression. Here, we present the results of a genome-wide miRNA expression profiling of HNE-treated HL-60 leukemic cells. Among 470 human miRNAs, 10 were found to be differentially expressed between control and HNE-treated cells (at p<0.05). Six miRNAs were down-regulated (miR-181a*, miR-199b, miR-202, miR-378, miR-454-3p, miR-575) and 4 were up-regulated (miR-125a, miR-339, miR-663, miR-660). Three of these regulated miRNAs (miR-202, miR-339, miR-378) were further assayed and validated by quantitative real-time RT-PCR. Moreover, consistent with the down-regulation of miR-378, HNE also induced the expression of the SUFU protein, a tumor suppressor recently identified as a target of miR-378. The finding that HNE could regulate the expression of miRNAs and their targets opens new perspectives on the understanding of HNE-controlled pathways. A functional analysis of 191 putative gene targets of miRNAs modulated by HNE is discussed.

Separation of integrin-dependent adhesion from morphological changes based on differential PLC specificities.

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Wooten, D K; Teague, T K; McIntyre, B W

1999-01-01

In normal lymphocytes an inside-out signal up-regulating integrin adhesion is followed by a ligand-mediated outside-in cell spreading signal. Protein kinase C (PKC) inhibition blocks lymphocyte adherence to and spreading on fibronectin. In contrast, putative PLC inhibitors yield distinct differences with respect to adhesion and morphology. The phosphatidylinositol-specific phospholipase C (PLC) inhibitor neomycin blocked spreading of CD3/CD28-activated T cells on fibronectin by disrupting adhesion. Furthermore, when an additional inside-out signal for fibronectin adhesion is unnecessary such as with HPB-ALL T leukemic or phorbol-myristate-acetate-treated normal T cells, neomycin treatment does not alter adhesion or morphology. However, the phosphatidylcholine-specific PLC inhibitor D609 abrogates cell spreading without affecting adhesion to fibronectin in these cells as well as the CD3/CD28-activated T cells. These results strongly suggest that inside-out signaling for the integrin alpha4beta1 in lymphocytes proceeds through phosphatidylinositol-specific PLC and PKC, whereas the outside-in signal utilizes phosphatidylcholine-specific PLC and PKC.

Graft-versus-Leukemia Effect Following Hematopoietic Stem Cell Transplantation for Leukemia

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Anne M. Dickinson

2017-06-01

Full Text Available The success of hematopoietic stem cell transplantation (HSCT lies with the ability of the engrafting immune system to remove residual leukemia cells via a graft-versus-leukemia effect (GvL, caused either spontaneously post-HSCT or via donor lymphocyte infusion. GvL effects can also be initiated by allogenic mismatched natural killer cells, antigen-specific T cells, and activated dendritic cells of leukemic origin. The history and further application of this GvL effect and the main mechanisms will be discussed and reviewed in this chapter.

Study of the quantitative, functional, cytogenetic, and immunoregulatory properties of bone marrow mesenchymal stem cells in patients with B-cell chronic lymphocytic leukemia.

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Pontikoglou, Charalampos; Kastrinaki, Maria-Christina; Klaus, Mirjam; Kalpadakis, Christina; Katonis, Pavlos; Alpantaki, Kalliopi; Pangalis, Gerassimos A; Papadaki, Helen A

2013-05-01

The bone marrow (BM) microenvironment has clearly been implicated in the pathogenesis of B-cell chronic lymphocytic leukemia (B-CLL). However, the potential involvement of BM stromal progenitors, the mesenchymal stem cells (MSCs), in the pathophysiology of the disease has not been extensively investigated. We expanded in vitro BM-MSCs from B-CLL patients (n=11) and healthy individuals (n=16) and comparatively assessed their reserves, proliferative potential, differentiation capacity, and immunoregulatory effects on T- and B-cells. We also evaluated the anti-apoptotic effect of patient-derived MSCs on leukemic cells and studied their cytogenetic characteristics in comparison to BM hematopoietic cells. B-CLL-derived BM MSCs exhibit a similar phenotype, differentiation potential, and ability to suppress T-cell proliferative responses as compared with MSCs from normal controls. Furthermore, they do not carry the cytogenetic abnormalities of the leukemic clone, and they exert a similar anti-apoptotic effect on leukemic cells and healthy donor-derived B-cells, as their normal counterparts. On the other hand, MSCs from B-CLL patients significantly promote normal B-cell proliferation and IgG production, in contrast to healthy-donor-derived MSCs. Furthermore, they have impaired reserves, defective cellular growth due to increased apoptotic cell death and exhibit aberrant production of stromal cell-derived factor 1, B-cell activating factor, a proliferation inducing ligand, and transforming growth factor β1, cytokines that are crucial for the survival/nourishing of the leukemic cells. We conclude that ex vivo expanded B-CLL-derived MSCs harbor intrinsic qualitative and quantitative abnormalities that may be implicated in disease development and/or progression.

Development Refractoriness of MLL-Rearranged Human B Cell Acute Leukemias to Reprogramming into Pluripotency

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Alvaro Muñoz-López

2016-10-01

Full Text Available Induced pluripotent stem cells (iPSCs are a powerful tool for disease modeling. They are routinely generated from healthy donors and patients from multiple cell types at different developmental stages. However, reprogramming leukemias is an extremely inefficient process. Few studies generated iPSCs from primary chronic myeloid leukemias, but iPSC generation from acute myeloid or lymphoid leukemias (ALL has not been achieved. We attempted to generate iPSCs from different subtypes of B-ALL to address the developmental impact of leukemic fusion genes. OKSM(L-expressing mono/polycistronic-, retroviral/lentiviral/episomal-, and Sendai virus vector-based reprogramming strategies failed to render iPSCs in vitro and in vivo. Addition of transcriptomic-epigenetic reprogramming “boosters” also failed to generate iPSCs from B cell blasts and B-ALL lines, and when iPSCs emerged they lacked leukemic fusion genes, demonstrating non-leukemic myeloid origin. Conversely, MLL-AF4-overexpressing hematopoietic stem cells/B progenitors were successfully reprogrammed, indicating that B cell origin and leukemic fusion gene were not reprogramming barriers. Global transcriptome/DNA methylome profiling suggested a developmental/differentiation refractoriness of MLL-rearranged B-ALL to reprogramming into pluripotency.

Characterization of activating mutations of NOTCH3 in T-cell acute lymphoblastic leukemia and anti-leukemic activity of NOTCH3 inhibitory antibodies.

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Bernasconi-Elias, P; Hu, T; Jenkins, D; Firestone, B; Gans, S; Kurth, E; Capodieci, P; Deplazes-Lauber, J; Petropoulos, K; Thiel, P; Ponsel, D; Hee Choi, S; LeMotte, P; London, A; Goetcshkes, M; Nolin, E; Jones, M D; Slocum, K; Kluk, M J; Weinstock, D M; Christodoulou, A; Weinberg, O; Jaehrling, J; Ettenberg, S A; Buckler, A; Blacklow, S C; Aster, J C; Fryer, C J

2016-11-24

Notch receptors have been implicated as oncogenic drivers in several cancers, the most notable example being NOTCH1 in T-cell acute lymphoblastic leukemia (T-ALL). To characterize the role of activated NOTCH3 in cancer, we generated an antibody that detects the neo-epitope created upon gamma-secretase cleavage of NOTCH3 to release its intracellular domain (ICD3), and sequenced the negative regulatory region (NRR) and PEST (proline, glutamate, serine, threonine) domain coding regions of NOTCH3 in a panel of cell lines. We also characterize NOTCH3 tumor-associated mutations that result in activation of signaling and report new inhibitory antibodies. We determined the structural basis for receptor inhibition by obtaining the first co-crystal structure of a NOTCH3 antibody with the NRR protein and defined two distinct epitopes for NRR antibodies. The antibodies exhibit potent anti-leukemic activity in cell lines and tumor xenografts harboring NOTCH3 activating mutations. Screening of primary T-ALL samples reveals that 2 of 40 tumors examined show active NOTCH3 signaling. We also identified evidence of NOTCH3 activation in 12 of 24 patient-derived orthotopic xenograft models, 2 of which exhibit activation of NOTCH3 without activation of NOTCH1. Our studies provide additional insights into NOTCH3 activation and offer a path forward for identification of cancers that are likely to respond to therapy with NOTCH3 selective inhibitory antibodies.

Pilot Study on Mass Spectrometry–Based Analysis of the Proteome of CD34+CD123+ Progenitor Cells for the Identification of Potential Targets for Immunotherapy in Acute Myeloid Leukemia

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Johannes R. Schmidt

2018-02-01

Full Text Available Targeting of leukemic stem cells with specific immunotherapy would be an ideal approach for the treatment of myeloid malignancies, but suitable epitopes are unknown. The comparative proteome-level characterization of hematopoietic stem and progenitor cells from healthy stem cell donors and patients with acute myeloid leukemia has the potential to reveal differentially expressed proteins which can be used as surface-markers or as proxies for affected molecular pathways. We employed mass spectrometry methods to analyze the proteome of the cytosolic and the membrane fraction of CD34 and CD123 co-expressing FACS-sorted leukemic progenitors from five patients with acute myeloid leukemia. As a reference, CD34+CD123+ normal hematopoietic progenitor cells from five healthy, granulocyte-colony stimulating factor (G-CSF mobilized stem cell donors were analyzed. In this Tandem Mass Tag (TMT 10-plex labelling–based approach, 2070 proteins were identified with 171 proteins differentially abundant in one or both cellular compartments. This proof-of-principle-study demonstrates the potential of mass spectrometry to detect differentially expressed proteins in two compartment fractions of the entire proteome of leukemic stem cells, compared to their non-malignant counterparts. This may contribute to future immunotherapeutic target discoveries and individualized AML patient characterization.

A 5-year old male with “leukemic form” of disseminated post-transplant lymphoproliferative disorder

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Saadiya Haque

2010-03-01

Full Text Available Post-transplant lymphoproliferative disorder (PTLD represents an abnormal lymphoid proliferation that occurs in recipients of solid organ or bone marrow allograft. It includes a diverse group of diseases ranging from polymorphic B-cell hyperplasia to frank malignant lymphoma. Clinical presentation is variable, ranging from asymptomatic to generalized lymphadenopathy, mononucleosis-like syndrome, nodal or extranodal tumors (usually gastrointestinal tract, systemic lymphomatous involvement, and rare (less than 1% of cases fulminant disseminated disease. PTLD is more common in children than in adults. Younger patients usually present with mononucleosis-like symptoms. We present an unusual case of a 5-year old male who developed a widely disseminated leukemic form of PTLD, involving lymph nodes, tonsils, multiple organs, bone marrow, cerebrospinal fluid, and peripheral blood.

The novel anticancer agent JNJ-26854165 is active in chronic myeloid leukemic cells with unmutated BCR/ABL and T315I mutant BCR/ABL through promoting proteosomal degradation of BCR/ABL proteins.

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You, Liangshun; Liu, Hui; Huang, Jian; Xie, Wanzhuo; Wei, Jueying; Ye, Xiujin; Qian, Wenbin

2017-01-31

Chronic myeloid leukemia (CML) is a clonal malignant disease caused by the expression of BCR/ABL. MDM2 (human homolog of the murine double minute-2) inhibitors such as Nutlin-3 have been shown to induce apoptosis in a p53-dependent manner in CML cells and sensitize cells to Imatinib. Here, we demonstrate that JNJ-26854165, an inhibitor of MDM2, inhibits proliferation and triggers cell death in a p53-independent manner in various BCR/ABL-expressing cells, which include primary leukemic cells from patients with CML blast crisis and cells expressing the Imatinib-resistant T315I BCR/ABL mutant. The response to JNJ-26854165 is associated with the downregulation of BCR/ABL dependently of proteosome activation. Moreover, in all tested CML cells, with the exception of T315I mutation cells, combining JNJ-26854165 and tyrosine kinase inhibitor (TKI) Imatinib or PD180970 leads to a synergistic effect. In conclusion, our results suggest that JNJ-26854165, used either alone or in combination with TKIs, represents a promising novel targeted approach to overcome TKI resistance and improve patient outcome in CML.

Trisomy 4 in a case of acute undifferentiated myeloblastic leukemia with hand-mirror cells.

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Kao, Y S; McCormick, C; Vial, R

1990-04-01

A case of acute undifferentiated myelocytic leukemic with trisomy 4 is described. The patient is a 61-year-old woman who developed leukemia 4 1/2 years after receiving radiation therapy for uterine carcinoma. Many leukemic cells exhibited hand-mirror configuration after the bone marrow aspirate was left at room temperature overnight. The relationship between trisomy 4 and hand-mirror cells in acute myelocytic leukemia is unknown.

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

Leukemia in AKR mice. III. Size distribution of suppressor T-cells in AKR leukemia and neonatal mice

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Mulder, A.M.; Durdik, J.M.; Toth, P.; Golub, E.S.

1978-01-01

Suppression of in vitro antibody forming potential of normal cells by leukemic cells of AKR and normal neonatal mice have many similarities. In both cases the suppression is by cell contact rather than by the elaboration of soluble suppressive factors and the suppression is sensitive to both x-irradiation and mitomycin C treatment. When the size distribution of suppressing cells in thymus and spleen were compared by velocity sedimentation, both leukemic and neonatal suppressing cells had similar size distribution in each organ. Both large and small cells in the thymus suppress but only large cells (sedimentation velocity > 3.5 mm/hr) in the spleen are able to suppress. Leukemic cells in lymph node have a splenic size distribution, viz., only large cells suppress. Both large and small cells of a subcutaneously growing long passage AKR lymphoma are able to suppress. While large cells contain the bulk of cells actively incorporating tritiated thymidine and thus probably in cycle, small but significant amounts of incorporation in small suppressing cells is also seen

C/EBPα is dispensable for the ontogeny of PD-1+ CD4+ memory T cells but restricts their expansion in an age-dependent manner.

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Norrie, Ida Christine; Ohlsson, Ewa; Nielsen, Olaf; Hasemann, Marie Sigurd; Porse, Bo T

2014-01-01

Ageing and cancer is often associated with altered T cell distributions and this phenomenon has been suggested to be the main driver in the development of immunosenescence. Memory phenotype PD-1+ CD4+ T cells accumulate with age and during leukemic development, and they might account for the attenuated T cell response in elderly or diseased individuals. The transcription factor C/EBPα has been suggested to be responsible for the accumulation as well as for the senescent features of these cells including impaired TCR signaling and decreased proliferation. Thus modulating the activity of C/EBPα could potentially target PD-1+ CD4+ T cells and consequently, impede the development of immunosenescence. To exploit this possibility we tested the importance of C/EBPα for the development of age-dependent PD-1+ CD4+ T cells as well as its role in the accumulation of PD-1+ CD4+ T cells during leukemic progression. In contrast to earlier suggestions, we find that loss of C/EBPα expression in the lymphoid compartment led to an increase of PD-1+ CD4+ T cells specifically in old mice, suggesting that C/EBPα repress the accumulation of these cells in elderly by inhibiting their proliferation. Furthermore, C/EBPα-deficiency in the lymphoid compartment had no effect on leukemic development and did not affect the accumulation of PD-1+ CD4+ T cells. Thus, in addition to contradict earlier suggestions of a role for C/EBPα in immunosenescence, these findings efficiently discard the potential of using C/EBPα as a target for the alleviation of ageing/cancer-associated immunosenescence.

The novel AML stem cell associated antigen CLL-1 aids in discrimination between normal and leukemic stem cells.

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van Rhenen, Anna; van Dongen, Guus A M S; Kelder, Angèle; Rombouts, Elwin J; Feller, Nicole; Moshaver, Bijan; Stigter-van Walsum, Marijke; Zweegman, Sonja; Ossenkoppele, Gert J; Jan Schuurhuis, Gerrit

2007-10-01

In CD34(+) acute myeloid leukemia (AML), the malignant stem cells reside in the CD38(-) compartment. We have shown before that the frequency of such CD34(+)CD38(-) cells at diagnosis correlates with minimal residual disease (MRD) frequency after chemotherapy and with survival. Specific targeting of CD34(+)CD38(-) cells might thus offer therapeutic options. Previously, we found that C-type lectin-like molecule-1 (CLL-1) has high expression on the whole blast compartment in the majority of AML cases. We now show that CLL-1 expression is also present on the CD34(+)CD38(-) stem- cell compartment in AML (77/89 patients). The CD34(+)CLL-1(+) population, containing the CD34(+)CD38(-)CLL-1(+) cells, does engraft in nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice with outgrowth to CLL-1(+) blasts. CLL-1 expression was not different between diagnosis and relapse (n = 9). In remission, both CLL-1(-) normal and CLL-1(+) malignant CD34(+)CD38(-) cells were present. A high CLL-1(+) fraction was associated with quick relapse. CLL-1 expression is completely absent both on CD34(+)CD38(-) cells in normal (n = 11) and in regenerating bone marrow controls (n = 6). This AML stem-cell specificity of the anti-CLL-1 antibody under all conditions of disease and the leukemia-initiating properties of CD34(+)CLL-1(+) cells indicate that anti-CLL-1 antibody enables both AML-specific stem-cell detection and possibly antigen-targeting in future.

Changes in T-cell subpopulations and cytokine network during early period of ibrutinib therapy in chronic lymphocytic leukemia patients: the significant decrease in T regulatory cells number.

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Podhorecka, Monika; Goracy, Aneta; Szymczyk, Agnieszka; Kowal, Malgorzata; Ibanez, Blanca; Jankowska-Lecka, Olga; Macheta, Arkadiusz; Nowaczynska, Aleksandra; Drab-Urbanek, Elzbieta; Chocholska, Sylwia; Jawniak, Dariusz; Hus, Marek

2017-05-23

B cell receptor (BCR) stimulation signal plays an important role in the pathogenesis of chronic lymphocytic leukemia (CLL), and kinase inhibitors directed toward the BCR pathway are now the promising anti-leukemic drugs. Ibrutinib, a Bruton tyrosine kinase inhibitor, demonstrates promising clinical activity in CLL. It is reported that ibrutinib, additionally to directly targeting leukemic cells, also inhibits the interactions of these cells with T cells, macrophages and accessory cells. Assessment of these mechanisms is important because of their non -direct anti-leukemic effects and to identify possible side effects connected with long-term drug administration.The aim of this study was to assess the in vivo effects of ibrutinib on T-cell subpopulations and cytokine network in CLL. The analysis was performed on a group of 19 patients during first month of ibrutinib therapy. The standard multicolor flow cytometry and cytometric bead array methods were used for assessment of T-cell subsets and cytokines/chemokines, respectively.The data obtained indicates that Ibrutinib treatment results in changes in T-cell subpopulations and cytokine network in CLL patients. Particularly, a significant reduction of T regulatory cells in peripheral blood was observed. By targeting these populations of T cells Ibrutinib can stimulate rejection of tumor cells by the immune system.

DENTAL CONSIDERATIONS FOR LEUKEMIC PEDIATRIC PATIENTS: AN UPDATED REVIEW FOR GENERAL DENTAL PRACTITIONER.

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Lowal, Kholoud A; Alaizari, Nader Ahmed; Tarakji, Bassel; Petro, Waleed; Hussain, Khaja Amjad; Altamimi, Mohamed Abdullah Alsakran

2015-10-01

The early signs of leukemia can usually manifest in the oral cavity due to infiltration of leukemic cells or due to associated decline in normal marrow elements, especially in the acute phase of leukemia, as common lesions at this stage of the disease can be screened and diagnosed by the dentist. Therefore, the dental community should be aware of the oral manifestations of leukemia and oral complications of anticancer treatment. This can eliminate the oral symptoms of the disease and to improve quality of life for these patients. An extensive search in PubMed line using a combination of terms like "leukemia, children, dental, Acute lymphoblastic leukemia, pediatric" for last ten years was made. Reviews and case reports concerned about acute lymphoblastic leukemia in children were all collected and analyzed and data were extracted. Accordingly, the aim of this review is to highlight on the oral presentations of leukemia in children attending dental clinics and the management of its undesirable side effects.

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)

Allogeneic cellular immunotherapy for chronic B-cell leukemia

NARCIS (Netherlands)

Hoogendoorn, Mels

2007-01-01

Allogeneic stem cell transplantation (SCT) following reduced-intensity conditioning (RIC) as treatment modality has curative potential in patients suffering from chronic lymphocytic leukemia (CLL) or mantle cell lymphoma (MCL), illustrating susceptibility of these leukemic cells for the

Detection of Ca2+-induced acetylcholine released from leukemic T-cells using an amperometric microfluidic sensor.

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Akhtar, Mahmood H; Hussain, Khalil K; Gurudatt, N G; Shim, Yoon-Bo

2017-12-15

A microfluidic structured-dual electrodes sensor comprising of a pair of screen printed carbon electrodes was fabricated to detect acetylcholine, where one of them was used for an enzyme reaction and another for a detection electrode. The former was coated with gold nanoparticles and the latter with a porous gold layer, followed by electropolymerization of 2, 2:5,2-terthiophene-3-(p-benzoic acid) (pTTBA) on both the electrodes. Then, acetylcholinesterase was covalently attached onto the reaction electrode, and hydrazine and choline oxidase were co-immobilized on the detection electrode. The layers of both modified electrodes were characterized employing voltammetry, field emission scanning electron microscopy, X-ray photoelectron spectroscopy, and quartz crystal microscopy. After the modifications of both electrode surfaces, they were precisely faced each other to form a microfluidic channel structure, where H 2 O 2 produced from the sequential enzymatic reactions was reduced by hydrazine to obtain the analytical signal which was analyzed by the detection electrode. The microfluidic sensor at the optimized experimental conditions exhibited a wide dynamic range from 0.7nM to 1500μM with the detection limit of 0.6 ± 0.1nM based on 3s (S/N = 3). The biomedical application of the proposed sensor was evaluated by detecting acetylcholine in human plasma samples. Moreover, the Ca 2+ -induced acetylcholine released in leukemic T-cells was also investigated to show the in vitro detection ability of the designed microfluidic sensor. Interference due to the real component matrix were also studied and long term stability of the designed sensor was evaluated. The analytical performance of the designed sensor was also compared with commercially available ACh detection kit. Copyright © 2017 Elsevier B.V. All rights reserved.

Comparison of Cytotoxic Activity in Leukemic Lineages Reveals Important Features of β-Hairpin Antimicrobial Peptides.

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Buri, Marcus V; Torquato, Heron F Vieira; Barros, Carlos Castilho; Ide, Jaime S; Miranda, Antonio; Paredes-Gamero, Edgar J

2017-07-01

Several reports described different modes of cell death triggered by antimicrobial peptides (AMPs) due to direct effects on membrane disruption, and more recently by apoptosis and necrosis-like patterns. Cytotoxic curves of four β-hairpin AMPs (gomesin, protegrin, tachyplesin, and polyphemusin) were obtained from several human leukemic lineages and normal monocytes and Two cell lines were then selected based on their cytotoxic sensitivity. One was sensitive to AMPs (K562) and the other resistant (KG-1) and their effect compared between these lineages. Thus, these lineages were chosen to further investigate biological features related with their cytotoxicities to AMPs. Stimulation with AMPs produced cell death, with activation of caspase-3, in K562 lineage. Increase on the fluidity of plasmatic membrane by reducing cholesterol potentiated cytotoxicity of AMPs in both lineages. Quantification of internal and external gomesin binding to the cellular membrane of both K562 and KG-1 cells showed that more peptide is accumulated inside of K562 cells. Additionally, evaluation of multi-drug resistant pumps activity showed that KG-1 has more activity than K562 lineage. A comparison of intrinsic gene patterns showed great differences between K562 and KG-1, but stimulation with gomesin promoted few changes in gene expression patterns. Differences in internalization process through the plasma membrane, multidrug resistance pumps activity, and gene expression pattern are important features to AMPs regulated cell death. J. Cell. Biochem. 118: 1764-1773, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

C/EBPα is dispensable for the ontogeny of PD-1+ CD4+ memory T cells but restricts their expansion in an age-dependent manner.

Directory of Open Access Journals (Sweden)

Ida Christine Norrie

Full Text Available Ageing and cancer is often associated with altered T cell distributions and this phenomenon has been suggested to be the main driver in the development of immunosenescence. Memory phenotype PD-1+ CD4+ T cells accumulate with age and during leukemic development, and they might account for the attenuated T cell response in elderly or diseased individuals. The transcription factor C/EBPα has been suggested to be responsible for the accumulation as well as for the senescent features of these cells including impaired TCR signaling and decreased proliferation. Thus modulating the activity of C/EBPα could potentially target PD-1+ CD4+ T cells and consequently, impede the development of immunosenescence. To exploit this possibility we tested the importance of C/EBPα for the development of age-dependent PD-1+ CD4+ T cells as well as its role in the accumulation of PD-1+ CD4+ T cells during leukemic progression. In contrast to earlier suggestions, we find that loss of C/EBPα expression in the lymphoid compartment led to an increase of PD-1+ CD4+ T cells specifically in old mice, suggesting that C/EBPα repress the accumulation of these cells in elderly by inhibiting their proliferation. Furthermore, C/EBPα-deficiency in the lymphoid compartment had no effect on leukemic development and did not affect the accumulation of PD-1+ CD4+ T cells. Thus, in addition to contradict earlier suggestions of a role for C/EBPα in immunosenescence, these findings efficiently discard the potential of using C/EBPα as a target for the alleviation of ageing/cancer-associated immunosenescence.

To the nucleolar density and size in apoptotic human leukemic myeloblasts produced in vitro by Trichostatin A

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K Smetana

2009-08-01

Full Text Available The present study was designed to provide more information on nucleoli in apoptotic cells, which were represented in the present study by cultured leukemic myeloblasts (Kasumi-1 cells. The apoptotic process in these cells was produced by trichostatin A (TSA that is a histone deacetylase inhibitor with strong cytostatic effects. The selected TSA concentration added to cultures facilitated to study apoptotic and notapoptotic cells in one and the same specimen. The nucleolar diameter and density were determined using computer assisted measurement and densitometry in specimens stained for RNA. In comparison with not-apoptotic cells, in apoptotic cells, nucleolar mean diameter did not change significantly and nucleolar RNA density was also not apparently different. On the other hand, the cytoplasmic RNA density in apoptotic cells was markedly reduced. Thus it seemed to be possible that the transcribed RNA remained “frozen” within the nucleolus but its transport to the cytoplasm decreased or stopped. However, the possibility of the RNA degradation in the cytoplasm of apoptotic cells based on the present study cannot be eliminated. At this occasion it should be added that AgNORs reflecting nucleolar biosynthetic and cell proliferation activity in apoptotic cells decreased in number or disappeared. The presented results also indicated that large nucleoli intensely stained for RNA need not be necessarily related to the high nucleolar biosynthetic or cell proliferation activity and may be also present in apoptotic cells responding to the cytostatic treatment.

Adult T-cell leukemia on the east coast of Kii Peninsula--presentation of an anti-ATLA-negative case.

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Karitani, Y; Kobayashi, T; Koh, T; Iwata, Y; Tanaka, I; Minami, N; Shirakawa, S

1983-01-01

Nineteen patients with adult T-cell leukemia (ATL) have been found in the last seven years along the east coast of Kii Peninsula in Japan. The leukemic cells were of the immunologically inducer/helper T-cell phenotype. The prognosis was very poor (median survival time, 85 days), and most of the patients had fatal complications of pulmonary infections. Antibody against ATL-associated antigen (anti-ATLA) was detected in sera from 9 of 10 patients who were born along the coast. However, it was not detected in one patient who was born in a district surrounded by mountains. Although he had neither superficial lymphadenopathy nor skin lesions, he showed rapid clinical deterioration. His leukemic cells appeared to be extremely bizarre with marked nuclear deformation compared with those of the other patients. In surface marker studies the leukemic cells reacted positively with OKT3, OKT4 and OKIa-1 monoclonal antibodies. The characteristics of the anti-ATLA-negative case are discussed in comparison with the other ATL cases.

Regulatory effects of sestrin 3 (SESN3 in BCR-ABL expressing cells.

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Eliza Vakana

Full Text Available Chronic myeloid leukemia (CML and Ph+ acute lymphoblastic leukemia (ALL are characterized by the presence of the BCR-ABL oncoprotein, which leads to activation of a plethora of pro-mitogenic and pro-survival pathways, including the mTOR signaling cascade. We provide evidence that in BCR-ABL expressing cells, treatment with tyrosine kinase inhibitors (TKIs results in upregulation of mRNA levels and protein expression of sestrin3 (SESN3, a unique cellular inhibitor of mTOR complex 1 (mTORC1. Such upregulation appears to be mediated by regulatory effects on mTOR, as catalytic inhibition of the mTOR kinase also induces SESN3. Catalytic mTOR inhibition also results in upregulation of SESN3 expression in cells harboring the TKI-insensitive T315I-BCR-ABL mutant, which is resistant to imatinib mesylate. Overexpression of SESN3 results in inhibitory effects on different Ph+ leukemic cell lines including KT-1-derived leukemic precursors, indicating that SESN3 mediates anti-leukemic responses in Ph+ cells. Altogether, our findings suggest the existence of a novel mechanism for the generation of antileukemic responses in CML cells, involving upregulation of SESN3 expression.

Human monoclonal antibodies reactive with human myelomonocytic leukemia cells.

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Posner, M R; Santos, D J; Elboim, H S; Tumber, M B; Frackelton, A R

1989-04-01

Peripheral blood mononuclear cells from a patient with chronic myelogenous leukemia (CML), in remission, were depleted of CD8-positive T-cells and cultured with Epstein-Barr virus. Four of 20 cultures (20%) secreted human IgG antibodies selectively reactive with the cell surfaces of certain human leukemia cell lines. Three polyclonal, Epstein-Barr virus-transformed, B-cell lines were expanded and fused with the human-mouse myeloma analogue HMMA2.11TG/O. Antibody from secreting clones HL 1.2 (IgG1), HL 2.1 (IgG3), and HL 3.1 (IgG1) have been characterized. All three react with HL-60 (promyelocytic), RWLeu4 (CML promyelocytic), and U937 (monocytic), but not with KG-1 (myeloblastic) or K562 (CML erythroid). There is no reactivity with T-cell lines, Burkitt's cell lines, pre-B-leukemia cell lines, or an undifferentiated CML cell line, BV173. Leukemic cells from two of seven patients with acute myelogenous leukemia and one of five with acute lymphocytic leukemia react with all three antibodies. Normal lymphocytes, monocytes, polymorphonuclear cells, red blood cells, bone marrow cells, and platelets do not react. Samples from patients with other diverse hematopoietic malignancies showed no reactivity. Immunoprecipitations suggest that the reactive antigen(s) is a lactoperoxidase iodinatable series of cell surface proteins with molecular weights of 42,000-54,000 and a noniodinatable protein with a molecular weight of 82,000. Based on these data these human monoclonal antibodies appear to react with myelomonocytic leukemic cells and may detect a leukemia-specific antigen or a highly restricted differentiation antigen.

Single cell analysis of normal and leukemic hematopoiesis.

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Povinelli, Benjamin J; Rodriguez-Meira, Alba; Mead, Adam J

2018-02-01

The hematopoietic system is well established as a paradigm for the study of cellular hierarchies, their disruption in disease and therapeutic use in regenerative medicine. Traditional approaches to study hematopoiesis involve purification of cell populations based on a small number of surface markers. However, such population-based analysis obscures underlying heterogeneity contained within any phenotypically defined cell population. This heterogeneity can only be resolved through single cell analysis. Recent advances in single cell techniques allow analysis of the genome, transcriptome, epigenome and proteome in single cells at an unprecedented scale. The application of these new single cell methods to investigate the hematopoietic system has led to paradigm shifts in our understanding of cellular heterogeneity in hematopoiesis and how this is disrupted in disease. In this review, we summarize how single cell techniques have been applied to the analysis of hematopoietic stem/progenitor cells in normal and malignant hematopoiesis, with a particular focus on recent advances in single-cell genomics, including how these might be utilized for clinical application. Copyright © 2017. Published by Elsevier Ltd.

A study on stability and medical implications for a complex delay model for CML with cell competition and treatment.

Science.gov (United States)

Rădulescu, I R; Cândea, D; Halanay, A

2014-12-21

We study a mathematical model describing the dynamics of leukemic and normal cell populations (stem-like and differentiated) in chronic myeloid leukemia (CML). This model is a system of four delay differential equations incorporating three types of cell division. The competition between normal and leukemic stem cell populations for the common microenvironment is taken into consideration. The stability of one steady state is investigated. The results are discussed via their medical interpretation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Experimental studies on the mechanism of leukemogenesis following the hemopoietic stem cell kinetics

Energy Technology Data Exchange (ETDEWEB)

Bessho, Masami; Hirashima, Kunitake (National Inst. of Radiological Sciences, Chiba (Japan))

1982-12-01

The mechanism of radiation-induced myeloid leukemogenesis was studied experimentally following the hemopoietic stem cell kinetics. Pluripotent stem cells (CFU-S) regarded as target cells to Friend virus (FV) were highly susceptible to leukemic cell transformation by FV during the regeneration period after irradiation. Experimental studies using RFM mice revealed that (1) the period of leukemic transformation closely corresponded to the prolonged suppressive period of CFU-C after irradiation, when significantly increased fraction of CFU-C is in S-phase, (2) the leukemic cell transformation after irradiation occurred earlier and more frequently than the overt leukemia, (3) some unknown host factors except cellular immunity played an important role in the establishment of overt leukemia, (4) lipopolysaccharide administrated after irradiation increased the incidence of myeloid leukemia whereas urethane decreased it. Another experimental systems using C3H/He mice bearing CSF-producing tumor revealed that the incidence of myeloid leukemia after a low-dose irradiation increased when CFU-S and CFU-C were proliferating and differentiating actively by the stimulus of CSF produced by the tumor. The mechanism of this phenomenon can be regarded as the activation of leukemia virus in irradiated bodies.

Identification of the Molecular Mechanisms Responsible for the Inhibition of Homing of AML Cells Triggered by CD44-Ligation

KAUST Repository

Al-Jifri, Ablah

2011-08-03

Acute Myeloid Leukemia (AML) is a cancerous disease that is defined by the inability to produce functional and mature blood cells, as well as the uncontrolled proliferation due to failure to undergo apoptosis of abnormal cells. The most common therapy for Leukemia, chemotherapy, has proven only to be partially efficient since it does not target the leukemic stem cells (LSCs) that have a high self-renewal and repopulation capacity and result in remission of the disease. Therefore targeting LSCs will provide more efficient therapy. One way to achieve this would be to inhibit their homing capability to the bone marrow. It has recently been shown that CD44, an adhesive molecule, plays a crucial role in cell trafficking and lodgement of both normal and leukemic stem cells. More importantly anti-CD44 monoclonal antibodies, along with its ability to induce differentiation of leukemic blasts, it inhibits specifically the homing capacity of LSCs to their micro-environmental niches. However, these molecular mechanisms that underlie the inhibition of homing have yet to be determined. To address these questions we conducted in vitro adhesion and blot-rolling assays to analyze the adherence and rolling capacity of these LSCs before and after treatment with anti-CD44 monoclonal antibody (mAb). Since glycosyltransferases play a crucial role in post translational carbohydrate decoration on adhesion molecules, we analyzed the expression (using quantitative PCR) of the different glycosyltransferases expressed in LSC\\'s before and after CD44 ligation (mAb treatment). Furthermore, we analyzed differentiation by flow cytometric analysis of treated and non-treated LSC\\'s. We anticipate that our results will set forth new insights into targeted therapies for AML.

A 7 YEAR-7-MONTH OLD BOY WITH LEUKEMIC RETINOPATHY

Directory of Open Access Journals (Sweden)

Ni Made Rini Suari

2013-10-01

Full Text Available Normal 0 false false false IN X-NONE X-NONE MicrosoftInternetExplorer4 Ocular problems in patient with leukemia which are called leukemic retinopathy and subhyaloid hemorrhage is one of its feature. Subhyaloid hemorrhage in children with acute lymphoblastic leukemia (ALL is rarely happened. We reported a boy 7 year 7 month old, complained sudden blurred vision on his both eyes and diagnosed with acute lymphoblastic leukemia. When patient had complained his vision, result of routine hematology showed anemia, thrombocytopenia, and leukocytosis. Treatment of leukemic retinopathy in this patient was supportive and causal therapy with transfusion of thrombocyte concentrate, hydration for leukocytosis, giving chemotherapy intrathecal methotrexate and systemic (vincristine, daunorubicin, L-asparginase. We found gradually undergone resolution of subhyaloid hemorrhages, visible flame shaped thin, and his vision recovered nearly completely to 6/6 OD and 6/20 OS /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

CCL22-specific T Cells

DEFF Research Database (Denmark)

Martinenaite, Evelina; Munir Ahmad, Shamaila; Hansen, Morten

2016-01-01

Tumor cells and tumor-infiltrating macrophages produce the chemokine CCL22, which attracts regulatory T cells (Tregs) into the tumor microenvironment, decreasing anticancer immunity. Here, we investigated the possibility of targeting CCL22-expressing cells by activating specific T cells. We...... analyzed the CCL22 protein signal sequence, identifying a human leukocyte antigen A2- (HLA-A2-) restricted peptide epitope, which we then used to stimulate peripheral blood mononuclear cells (PMBCs) to expand populations of CCL22-specific T cells in vitro. T cells recognizing an epitope derived from...... the signal-peptide of CCL22 will recognize CCL22-expressing cells even though CCL22 is secreted out of the cell. CCL22-specific T cells recognized and killed CCL22-expressing cancer cells. Furthermore, CCL22-specific T cells lysed acute monocytic leukemia cells in a CCL22 expression-dependent manner. Using...

Role of the B-cell receptor in chronic lymphocytic leukemia: where do we stand?

Science.gov (United States)

Fais, Franco; Bruno, Silvia; Ghiotto, Fabio

2010-01-01

The past 15 years have witnessed an enormous effort in studying B-cell Chronic Lymphocytic Leukemia. A great number of researches brought significant novel information and a better understanding of the natural history of this disease. This mini review will focus on the studies related to the Immunoglobulin variable (IgV) genes rearrangements that compose the B-cell receptor (BcR) of the leukemic clones. These studies have defined a role for the antigen(s) in the paths that lead to leukemic clone generation/expansion and underscore the informative value represented by BcR analyses.

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.

Intramuscular leukemic relapse: clinical signs and imaging findings. A multicentric analysis

Energy Technology Data Exchange (ETDEWEB)

Surov, Alexey [Martin Luther University Halle-Wittenberg, Department of Radiology, Halle (Germany); University of Leipzig, Department of Diagnostic and Interventional Radiology, Leipzig (Germany); Kiratli, Hayyam [Hacettepe University School of Medicine, Department of Ophthalmology, Ankara (Turkey); Im, Soo Ah [Seoul St. Mary' s Hospital, Department of Radiology, Seoul (Korea, Republic of); Manabe, Yasuhiro [National Hospital Organization Okayama Medical Center, Department of Neurology, Okayama (Japan); O' Neill, Alibhe; Shinagare, Atul B. [Brigham and Women' s Hospital, Department of Radiology, Boston, MA (United States); Spielmann, Rolf Peter [Martin Luther University Halle-Wittenberg, Department of Radiology, Halle (Germany)

2014-09-26

Leukemia is a group of malignant diseases involving peripheral blood and bone marrow. Extramedullary tumor manifestation in leukemia can also occur. They more often involve lymph nodes, skin, and bones. Intramuscular leukemic relapse (ILR) is very unusual. The aim of this analysis was to summarize the reported data regarding clinical signs and radiological features of ILR. The PubMed database was searched for publications related to ILR. After an analysis of all identified articles, 20 publications matched the inclusion criteria. The authors of the 20 publications were contacted and provided imaging of their cases for review. The following were recorded: age, gender, primary diagnosis, clinical signs, pattern, localization and size of the intramuscular leukemic relapse. Images of 16 patients were provided [8 computer tomographic (CT) images and 15 magnetic resonance images, MRI]. Furthermore, one patient with ILR was identified in our institutional database. Therefore, images of 17 patients were available for further analysis. Overall, 32 cases with ILR were included in the analysis. In most cases acute myeloid leukemia was diagnosed. Most ILRs were localized in the extremities (44 %) and in the extraocular muscles (44 %). Clinically, ILR manifested as local pain, swelling and muscle weakness. Radiologically, ILR presented most frequently with diffuse muscle infiltration. On postcontrast CT/MRI, most lesions demonstrated homogeneous enhancement. ILRs were hypo-/isointense on T1w and hyperintense on T2w images. ILR manifests commonly as focal pain, swelling and muscle weakness. ILR predominantly involved the extraocular musculature and the extremities. Radiologically, diffuse muscle infiltration was the most common imaging finding. (orig.)

Effective control of acute myeloid leukaemia and acute lymphoblastic leukaemia progression by telomerase specific adoptive T-cell therapy.

Science.gov (United States)

Sandri, Sara; De Sanctis, Francesco; Lamolinara, Alessia; Boschi, Federico; Poffe, Ornella; Trovato, Rosalinda; Fiore, Alessandra; Sartori, Sara; Sbarbati, Andrea; Bondanza, Attilio; Cesaro, Simone; Krampera, Mauro; Scupoli, Maria T; Nishimura, Michael I; Iezzi, Manuela; Sartoris, Silvia; Bronte, Vincenzo; Ugel, Stefano

2017-10-20

Telomerase (TERT) is a ribonucleoprotein enzyme that preserves the molecular organization at the ends of eukaryotic chromosomes. Since TERT deregulation is a common step in leukaemia, treatments targeting telomerase might be useful for the therapy of hematologic malignancies. Despite a large spectrum of potential drugs, their bench-to-bedside translation is quite limited, with only a therapeutic vaccine in the clinic and a telomerase inhibitor at late stage of preclinical validation. We recently demonstrated that the adoptive transfer of T cell transduced with an HLA-A2-restricted T-cell receptor (TCR), which recognize human TERT with high avidity, controls human B-cell chronic lymphocytic leukaemia (B-CLL) progression without severe side-effects in humanized mice. In the present report, we show the ability of our approach to limit the progression of more aggressive leukemic pathologies, such as acute myeloid leukaemia (AML) and B-cell acute lymphoblastic leukaemia (B-ALL). Together, our findings demonstrate that TERT-based adoptive cell therapy is a concrete platform of T cell-mediated immunotherapy for leukaemia treatment.

Metastasis and growth of friend tumor cells in irradiated syngeneic hosts

International Nuclear Information System (INIS)

Matioli, G.

1974-01-01

Friend tumor cells (FTC) have been studied by growing them in lethally irradiated syngeneic mice. After establishing the FTC dilution factor (delta), extinction factor (Q), and the optimal time for colony counts, the FTC kinetic was analyzed by the recovery curve method. It was found that FTC growth is different from that experienced by normal or leukemic Friend stem cells when tested by the same in vivo assay. The most interesting differences were the high metastatic activity, the lack of differentiation, the deterministic growth, and the independence from the spleen microenvironment experienced by the FTC, in contrast with the normal and leukemic stem cells. In addition, the estimate of the critical size the FTC colony has to reach before releasing the first metastatic cells is presented. (U.S.)

Transglutaminase 2 expression in acute myeloid leukemia: Association with adhesion molecule expression and leukemic blast motility

Science.gov (United States)

Meyer, Stefan; Ravandi-Kashani, Farhad; Borthakur, Gautam; Coombes, Kevin R.; Zhang, Nianxiang; Kornblau, Steven

2016-01-01

Acute myeloid leukemia (AML) is a heterogenous disease with differential oncogene association, outcome and treatment regimens. Treatment strategies for AML have improved outcome but despite increased molecular biological information AML is still associated with poor prognosis. Proteomic analysis on the effects of a range of leukemogenic oncogenes showed that the protein transglutaminase 2 (TG2) is expressed at greater levels as a consequence of oncogenic transformation. Further analysis of this observation was performed with 511 AML samples using reverse phase proteomic arrays, demonstrating that TG2 expression was higher at relapse than diagnosis in many cases. In addition elevated TG2 expression correlated with increased expression of numerous adhesion proteins and many apoptosis regulating proteins, two processes related to leukemogenesis. TG2 has previously been linked to drug resistance in cancer and given the negative correlation between TG2 levels and peripheral blasts observed increased TG2 levels may lead to the protection of the leukemic stem cell due to increased adhesion/reduced motility. TG2 may therefore form part of a network of proteins that define poor outcome in AML patients and potentially offer a target to sensitize AML stem cells to drug treatment. PMID:23576428

NK-like homeodomain proteins activate NOTCH3-signaling in leukemic T-cells

International Nuclear Information System (INIS)

Nagel, Stefan; Scherr, Michaela; MacLeod, Roderick AF; Venturini, Letizia; Przybylski, Grzegorz K; Grabarczyk, Piotr; Meyer, Corinna; Kaufmann, Maren; Battmer, Karin; Schmidt, Christian A; Drexler, Hans G

2009-01-01

Homeodomain proteins control fundamental cellular processes in development and in cancer if deregulated. Three members of the NK-like subfamily of homeobox genes (NKLs), TLX1, TLX3 and NKX2-5, are implicated in T-cell acute lymphoblastic leukemia (T-ALL). They are activated by particular chromosomal aberrations. However, their precise function in leukemogenesis is still unclear. Here we screened further NKLs in 24 T-ALL cell lines and identified the common expression of MSX2. The subsequent aim of this study was to analyze the role of MSX2 in T-cell differentiation which may be disturbed by oncogenic NKLs. Specific gene activity was examined by quantitative real-time PCR, and globally by expression profiling. Proteins were analyzed by western blot, immuno-cytology and immuno-precipitation. For overexpression studies cell lines were transduced by lentiviruses. Quantification of MSX2 mRNA in primary hematopoietic cells demonstrated higher levels in CD34+ stem cells as compared to peripheral blood cells and mature CD3+ T-cells. Furthermore, analysis of MSX2 expression levels in T-cell lines after treatment with core thymic factors confirmed their involvement in regulation. These results indicated that MSX2 represents an hematopoietic NKL family member which is downregulated during T-cell development and may functionally substituted by oncogenic NKLs. For functional analysis JURKAT cells were lentivirally transduced, overexpressing either MSX2 or oncogenic TLX1 and NKX2-5, respectively. These cells displayed transcriptional activation of NOTCH3-signaling, including NOTCH3 and HEY1 as analyzed by gene expression profiling and quantitative RT-PCR, and consistently attenuated sensitivity to gamma-secretase inhibitor as analyzed by MTT-assays. Furthermore, in addition to MSX2, both TLX1 and NKX2-5 proteins interacted with NOTCH-pathway repressors, SPEN/MINT/SHARP and TLE1/GRG1, representing a potential mechanism for (de)regulation. Finally, elevated expression of NOTCH3

The Role of Mitochondrial DNA Damage and Repair in the Resistance of BCR/ABL-Expressing Cells to Tyrosine Kinase Inhibitors

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Janusz Blasiak

2013-08-01

Full Text Available Chronic myeloid leukemia (CML is a hematological malignancy that arises from the transformation of stem hematopoietic cells by the fusion oncogene BCR/ABL and subsequent clonal expansion of BCR/ABL-positive progenitor leukemic cells. The BCR/ABL protein displays a constitutively increased tyrosine kinase activity that alters many regulatory pathways, leading to uncontrolled growth, impaired differentiation and increased resistance to apoptosis featured by leukemic cells. Current CML therapy is based on tyrosine kinase inhibitors (TKIs, primarily imatinib, which induce apoptosis in leukemic cells. However, some patients show primary resistance to TKIs while others develop it in the course of therapy. In both cases, resistance may be underlined by perturbations in apoptotic signaling in leukemic cells. As mitochondria may play an important role in such signaling, alteration in mitochondrial metabolism may change resistance to pro-apoptotic action of TKIs in BCR/ABL-positive cells. Because BCR/ABL may induce reactive oxygen species and unfaithful DNA repair, it may affect the stability of mitochondrial DNA, influencing mitochondrial apoptotic signaling and in this way change the sensitivity of CML cells to TKIs. Moreover, cancer cells, including BCR/ABL-positive cells, show an increased level of glucose metabolism, resulting from the shift from oxidative phosphorylation to glycolysis to supply ATP for extensive proliferation. Enhanced level of glycolysis may be associated with TKI resistance and requires change in the expression of several genes regulated mostly by hypoxia-inducible factor-1α, HIF-1α. Such regulation may be associated with the impaired mitochondrial respiratory system in CML cells. In summary, mitochondria and mitochondria-associated molecules and pathways may be attractive targets to overcome TKI resistance in CML.

STAT3-mediated constitutive expression of SOCS-3 in cutaneous T-cell lymphoma

DEFF Research Database (Denmark)

Brender, C; Nielsen, M; Kaltoft, K

2001-01-01

) obtained from affected skin from a patient with mycosis fungoides (MF) and from peripheral blood from a patient with Sezary syndrome (SS). In contrast, constitutive SOCS-3 expression is not found in the leukemic Jurkat T-cell line, the MOLT-4 acute lymphoblastic leukemia cell line, and the monocytic......, it has been hypothesized that an aberrant SOCS expression plays a role in neoplastic transformation. This study reports on a constitutive SOCS-3 expression in cutaneous T-cell lymphoma (CTCL) cell lines. SOCS-3 protein is constitutively expressed in tumor cell lines (but not in nonmalignant T cells...... leukemic cell line U937. Expression of SOCS-3 coincides with a constitutive activation of STAT3 in CTCL tumor cells, and stable transfection of CTCL tumor cells with a dominant negative STAT3 strongly inhibits SOCS-3 expression, whereas transfection with wild-type STAT3 does not. Moreover, the reduced SOCS...

Homotypic aggregation of human cell lines by HLA class II-, class Ia- and HLA-G-specific monoclonal antibodies

DEFF Research Database (Denmark)

Odum, Niels; Ledbetter, J A; Martin, P

1991-01-01

Major histocompatibility complex (MHC) class II molecules have been implicated in cell adhesion in two ways. In addition to the well-established role of class II antigens in low-affinity adhesion provided by interactions between class II and CD4, recent data indicated that class II may also induce...... adhesion between T and B cells by activating the CD18/CD11a (LFA-1) adhesion pathway. Here we report that monoclonal antibodies (mAb) against HLA-DR (L243, p4.1, HB10a, VI15) and certain broad class II reacting mAb (TU35, TU39), but not anti-DQ (TU22, Leu-10) mAb, induced homotypic aggregation of human...... class II-positive monocytic (I937) and T leukemic (HUT78) tumor cell lines and Epstein-Barr virus (EBV) transformed B-lymphoid cell lines (EBV-LCL). Class II-negative cell lines (U-937 and the EBV-LCL mutant line 616) were not induced to aggregate. An HLA-G-transfected EBV-LCL, 221-AGN...

Human T cell leukemia virus type I prevents cell surface expression of the T cell receptor through down-regulation of the CD3-gamma, -delta, -epsilon, and -zeta genes

NARCIS (Netherlands)

de Waal Malefyt, R.; Yssel, H.; Spits, H.; de Vries, J. E.; Sancho, J.; Terhorst, C.; Alarcon, B.

1990-01-01

Infection and transformation by human T cell leukemia virus type I (HTLV-I) up-regulates expression of several inducible genes including those coding for cytokines involved in the proliferation of normal and leukemic T cells. We demonstrate that HTLV-I can also shut off expression of the CD3-gamma,

Stimulation of granulocytic cell iodination by pine cone antitumor substances

International Nuclear Information System (INIS)

Unten, S.; Sakagami, H.; Konno, K.

1989-01-01

Antitumor substances (Fractions VI and VII) prepared from the NaOH extract of pine cone significantly stimulated the iodination (incorporation of radioactive iodine into an acid-insoluble fraction) of human peripheral blood adherent mononuclear cells, polymorphonuclear cells (PMN), and human promyelocytic leukemic HL-60 cells. In contrast, these fractions did not significantly increase the iodination of nonadherent mononuclear cells, red blood cells, other human leukemic cell lines (U-937, THP-1, K-562), human diploid fibroblast (UT20Lu), or mouse cell lines (L-929, J774.1). Iodination of HL-60 cells, which were induced to differentiate by treatment with either retinoic acid or tumor necrosis factor, were stimulated less than untreated cells. The stimulation of iodination of both PMN and HL-60 cells required the continuous presence of these fractions and was almost completely abolished by the presence of myeloperoxidase inhibitors. The stimulation activity of these fractions was generally higher than that of various other immunopotentiators. Possible mechanisms of extract stimulation of myeloperoxidase-containing cell iodination are discussed

Lymphocyte-specific protein tyrosine kinase (Lck) interacts with CR6-interacting factor 1 (CRIF1) in mitochondria to repress oxidative phosphorylation

International Nuclear Information System (INIS)

Vahedi, Shahrooz; Chueh, Fu-Yu; Chandran, Bala; Yu, Chao-Lan

2015-01-01

Many cancer cells exhibit reduced mitochondrial respiration as part of metabolic reprogramming to support tumor growth. Mitochondrial localization of several protein tyrosine kinases is linked to this characteristic metabolic shift in solid tumors, but remains largely unknown in blood cancer. Lymphocyte-specific protein tyrosine kinase (Lck) is a key T-cell kinase and widely implicated in blood malignancies. The purpose of our study is to determine whether and how Lck contributes to metabolic shift in T-cell leukemia through mitochondrial localization. We compared the human leukemic T-cell line Jurkat with its Lck-deficient derivative Jcam cell line. Differences in mitochondrial respiration were measured by the levels of mitochondrial membrane potential, oxygen consumption, and mitochondrial superoxide. Detailed mitochondrial structure was visualized by transmission electron microscopy. Lck localization was evaluated by subcellular fractionation and confocal microscopy. Proteomic analysis was performed to identify proteins co-precipitated with Lck in leukemic T-cells. Protein interaction was validated by biochemical co-precipitation and confocal microscopy, followed by in situ proximity ligation assay microscopy to confirm close-range (<16 nm) interaction. Jurkat cells have abnormal mitochondrial structure and reduced levels of mitochondrial respiration, which is associated with the presence of mitochondrial Lck and lower levels of mitochondrion-encoded electron transport chain proteins. Proteomics identified CR6-interacting factor 1 (CRIF1) as the novel Lck-interacting protein. Lck association with CRIF1 in Jurkat mitochondria was confirmed biochemically and by microscopy, but did not lead to CRIF1 tyrosine phosphorylation. Consistent with the role of CRIF1 in functional mitoribosome, shRNA-mediated silencing of CRIF1 in Jcam resulted in mitochondrial dysfunction similar to that observed in Jurkat. Reduced interaction between CRIF1 and Tid1, another key component

In vitro anti-leukemic activity and chemical transformation of the 5'-chloro-5'-deoxy derivative of cyclo-cytidine

International Nuclear Information System (INIS)

Stankovicova, M.; Bachrata, M.; Sveda, P.; Rauko, P.; Blesova, P.

1995-01-01

Hydrochloride of 5'-chloro-5'-deoxy-cytocytidine (Cl-cC) is an analogue of hydrochloride (cC), a pro-drug of the compound with of the compound with the strong anti-leukemic activity arabinosylcytosine (araC). This paper is devoted to the study of its cytotoxic activity in vitro and to the effect of acid alkaline conditions and temperature on its stability. Cl-cC inhibits not only the growth of L1210 leukemia cells in vitro and the DNA synthesis (IC 50 = 0.09 μmol/dm 3 ) but, at the same time, it has a weak effect on RNA synthesis (IC 50 > 250 μmol/dm 3 ) and no effect on proteosynthesis. In alkaline conditions Cl-cC is transformed to 5'-chloro-araC and 2',5'-anhydro-araC but is more stable in acid solutions. (author)

Monoclonal antibody studies in B(non-T)-cell malignancies.

Science.gov (United States)

Shimoyama, M; Minato, K; Tobinai, K; Nagai, M; Hirose, M

1983-09-01

Tumor cells suspensions prepared from 129 B- or non-T cell malignancies were investigated with a panel of 10 monoclonal antibodies and conventional surface marker techniques. Surface immunoglobulin (sIg) and B1 antigen proved to be the most useful markers for B-cell lineage. Six major subtypes of acute lymphoblastic leukemia (ALL) of non-T cell nature are now recognized by these immunological techniques, including null-ALL, Ia-ALL, lymphoid stem cell ALL, pre-pre-B ALL, pre-B ALL and B-ALL. In cases of chronic leukemias and lymphomas of non-T cell nature, 80% of the tumor was defined by sIg and 88% by B1 antigen as definitely of B-cell lineage. The clonal character was also defined in 68% of the tumor on the basis of the detection of predominant single light chain in sIg. Ia-like antigen was detected in almost all cases (96%). Leukemic cells from all cases of chronic lymphocytic leukemia (CLL), chronic lymphosarcoma cell leukemia (CLsCL) and hairy cell leukemia (HCL) reacted with OKIa1 and anti-B1, and leukemic cells from most of them with anti-pan T monoclonal antibody (10.2). In more than half of CLL and CLsCL, leukemic cells were reactive with J5, OKM1, 9.6 and OKT8, but not with OKT3, OKT4 and OKT6. HCL cells had almost the same reactivity with these monoclonal antibodies as CLL and CLsCL cells except that J5 remained unreactive. These results indicated that Japanese CLL, CLsCL and HCL were different from Western ones at least with respect to surface marker characteristics. In cases of lymphomas, heavy chains of sIg were expressed in polyclonal fashion, especially in follicular lymphoma and diffuse lymphomas of medium sized cell type and large cell type, indicating that lymphomas of these types may originate from follicular center cells of the heavy chain switching stage. Anti-T monoclonals were also reactive with lymphoma cells. In about half of follicular lymphomas and diffuse lymphomas of the medium sized cell type, lymphoma cells reacted with 10.2, and less

A micro-Raman spectroscopic investigation of leukemic U-937 cells in aged cultures

Science.gov (United States)

Fazio, Enza; Trusso, Sebastiano; Franco, Domenico; Nicolò, Marco Sebastiano; Allegra, Alessandro; Neri, Fortunato; Musolino, Caterina; Guglielmino, Salvatore P. P.

2016-04-01

Recently it has been shown that micro-Raman spectroscopy combined with multivariate analysis is able to discriminate among different types of tissues and tumoral cells by the detection of significant alterations and/or reorganizations of complex biological molecules, such as nucleic acids, lipids and proteins. Moreover, its use, being in principle a non-invasive technique, appears an interesting clinical tool for the evaluation of the therapeutical effects and of the disease progression. In this work we analyzed molecular changes in aged cultures of leukemia model U937 cells with respect to fresh cultures of the same cell line. In fact, structural variations of individual neoplastic cells on aging may lead to a heterogeneous data set, therefore falsifying confidence intervals, increasing error levels of analysis and consequently limiting the use of Raman spectroscopy analysis. We found that the observed morphological changes of U937 cells corresponded to well defined modifications of the Raman contributions in selected spectral regions, where markers of specific functional groups, useful to characterize the cell state, are present. A detailed subcellular analysis showed a change in cellular organization as a function of time, and correlated to a significant increase of apoptosis levels. Besides the aforementioned study, Raman spectra were used as input for principal component analysis (PCA) in order to detect and classify spectral changes among U937 cells.

Therapeutic Effects of Myeloid Cell Leukemia-1 siRNA on Human Acute Myeloid Leukemia Cells

Directory of Open Access Journals (Sweden)

Hadi Karami

2014-05-01

Full Text Available Purpose: Up-regulation of Mcl-1, a known anti-apoptotic protein, is associated with the survival and progression of various malignancies including leukemia. The aim of this study was to explore the effect of Mcl-1 small interference RNA (siRNA on the proliferation and apoptosis of HL-60 acute myeloid leukemia (AML cells. Methods: siRNA transfection was performed using Lipofectamine™2000 reagent. Relative mRNA and protein expressions were quantified by quantitative real-time PCR and Western blotting, respectively. Trypan blue assay was performed to assess tumor cell proliferation after siRNA transfection. The cytotoxic effect of Mcl-1 siRNA on leukemic cells was measured using MTT assay. Apoptosis was detected using ELISA cell death assay. Results: Mcl-1 siRNA clearly lowered both Mcl-1 mRNA and protein levels in a time-dependent manner, leading to marked inhibition of cell survival and proliferation. Furthermore, Mcl-1 down-regulation significantly enhanced the extent of HL-60 apoptotic cells. Conclusion: Our results suggest that the down-regulation of Mcl-1 by siRNA can effectively trigger apoptosis and inhibit the proliferation of leukemic cells. Therefore, Mcl-1 siRNA may be a potent adjuvant in AML therapy.

Cell-cycle phase specificity of chloroethylnitrosoureas

International Nuclear Information System (INIS)

Linfoot, P.A.

1986-01-01

Although the cancer chemotherapeutic agent 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) is considered a non-cell cycle phase specific drug, it has been shown to produce differential cell killing in G 1 , S, and G 2 /M phase cells, with S phase cells appearing relatively resistant. Studies of cell cycle phase specific cell killing produced by nitrosoureas with different chemical reactivities, clearly indicated that the ability of compounds to cross-link DNA was important in determining their phase specificity. Cells that lacked guanine O 6 -alkytransferase activity showed similar patterns of BCNU phase specificity regardless of their intrinsic sensitivity to BCNU. DNA inter-strand cross-linking, as measured by alkaline elution, was similar in cells exposed to BCNU in G 1 or S phase. 3 H [1-chloroethyl-1nitrosourea] binding to DNA was the same in G 1 , S and G 2 /M phase cells indicating that phase-specific differences in drug uptake and intracellular drug dose were not responsible for phase specific cell kill. These studies suggest that cross-link lesions, other than DNA inter-strand cross-links, and/or effects on DNA repair, other than guanine O 6 -alkyltransferase, are additional important determinants of BCNU phase specific cell killing

Metabolism modifications and apoptosis induction after Cellfood™ administration to leukemia cell lines.

Science.gov (United States)

Catalani, Simona; Carbonaro, Valentina; Palma, Francesco; Arshakyan, Marselina; Galati, Rossella; Nuvoli, Barbara; Battistelli, Serafina; Canestrari, Franco; Benedetti, Serena

2013-09-09

Cellfood™ (CF) is a nutritional supplement containing deuterium sulphate, minerals, amino acids, and enzymes, with well documented antioxidant properties. Its organic and inorganic components are extracted from the red algae Lithothamnion calcareum, whose mineral extract has shown growth-inhibitory effect both on in vitro and in vivo models. The purpose of this study was to evaluate the antiproliferative effects of CF on leukemic cells. In fact, according to its capacity to modulate O2 availability and to improve mitochondrial respiratory metabolism, we wondered if CF could affect cancer cell metabolism making cells susceptible to apoptosis. Three leukemic cell lines, Jurkat, U937, and K562, were treated with CF 5 μl/ml up to 72 hours. Cell viability, apoptosis (i.e. caspase-3 activity and DNA fragmentation), hypoxia inducible factor 1 alpha (HIF-1α) concentration, glucose transporter 1 (GLUT-1) expression, lactate dehydrogenase (LDH) activity and lactate release in the culture medium were detected and compared with untreated cells. CF significantly inhibited leukemic cell viability by promoting cell apoptosis, as revealed by caspase-3 activation and DNA laddering. In particular, CF treated cells showed lower HIF-1α levels and lower GLUT-1 expression as compared to untreated cells. At the same time, CF was able to reduce LDH activity and, consequently, the amount of lactate released in the extracellular environment. We supplied evidence for an antiproliferative effect of CF on leukemia cell lines by inducing cell death through an apoptotic mechanism and by altering cancer cell metabolism through HIF-1α and GLUT-1 regulation. Thanks to its antioxidative and proapoptotic properties, CF might be a good candidate for cancer prevention.

PU.1 silencing leads to terminal differentiation of erythroleukemia cells

International Nuclear Information System (INIS)

Atar, Orna; Levi, Ben-Zion

2005-01-01

The transcription factor PU.1 plays a central role in development and differentiation of hematopoietic cells. Evidence from PU.1 knockout mice indicates a pivotal role for PU.1 in myeloid lineage and B-lymphocyte development. In addition, PU.1 is a key player in the development of Friend erythroleukemia disease, which is characterized by proliferation and differentiation arrest of proerythrocytes. To study the role of PU.1 in erythroleukemia, we have used murine erythroleukemia cells, isolated from Friend virus-infected mice. Expression of PU.1 small interfering RNA in these cells led to significant inhibition of PU.1 levels. This was accompanied by inhibition of proliferation and restoration in the ability of the proerythroblastic cells to produce hemoglobin, i.e., reversion of the leukemic phenotype. The data suggest that overexpression of PU.1 gene is the immediate cause for maintaining the leukemic phenotype of the disease by retaining the self-renewal capacity of transformed erythroblastic cells and by blocking the terminal differentiation program towards erythrocytes

Assay of hybrid ribonuclease using a membrane filter-immobilized synthetic hybrid: application to the human leukemic cell

International Nuclear Information System (INIS)

Papaphilis, A.D.; Kamper, E.F.

1985-01-01

A method for assaying hybrid ribonuclease has been devised which utilizes as substrate the synthetic hybrid [ 3 H]polyriboadenylic acid [poly(rA)]:polydeoxythymidylic acid [poly(dT)] immobilized on the solid matrix of nitrocellulose filters. The hybridization on filter of [ 3 H]poly(rA) to poly(dT) has been explored in terms of efficacy of the process and the response of the product to RNase H. A pulse of uv irradiation of poly(dT) while in dry state on the filter increased its firm binding to the filter in a concentration-dependent manner, resulting in a concomitant increase of the yield of hybrid formation. The filter-immobilized hybrid was 95% resistant to RNase A but sensitive to RNase H. When stored in toluene in the cold the hybrid maintained its stability for over 6 months, as judged by its resistance to RNase A. The method offers a number of advantages over assays that use solution hybrids as substrates and was readily applicable in the screening of leukemic patients, in the leukocytes of which it has demonstrated increased RNase H levels

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

Energy Technology Data Exchange (ETDEWEB)

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.

Macrophage inflammatory protein-3α influences growth of K562 leukemia cells in co-culture with anticancer drug-pretreated HS-5 stromal cells

International Nuclear Information System (INIS)

Lee, Y.C.; Chiou, T.-J.; Tzeng, W.-F.; Chu, S.T.

2008-01-01

Stromal cell monolayers have been an important means of studying the regulation of hematopoiesis, because they produce cytokines. Cytosine arabinoside, vincristine, daunorubicin, and doxorubicin are common drugs for hematological cancer therapy, and they may have some effects on bone marrow stroma during chemotherapy. The aim of this study was to elucidate interactions between the bone marrow stromal microenvironment and leukemic cells after drug treatment. We tested the hypothesis that human HS-5 stromal cells, pretreated with anticancer drugs, affected the growth of leukemic K562 cells by changing the cytokines in the culture microenvironment. Thereafter, proliferation of K562 cells increased nearly 2.5-fold compared the co-cultivation with drugs-pretreated HS-5 stromal cells and drugs-untreated HS-5 stromal cells. The results indicated that co-cultivation with HS-5 stromal cells pretreated with drugs caused significant K562 cell proliferation. Cytokines in the microenvironment were detected via the RayBio Human Cytokine Antibody Array Membrane. The levels of the cytokines CKβ, IL-12, IL-13, IGFBP-2, MCP-1, MCP-3, MCP-4, MDC, MIP-1β and MIP-1δ were decreased, with a particularly marked decrease in MIP-3α. In co-culture medium, there was a 20-fold decrease in MIP-3α in daunorubicin-pretreated HS-5 cells and at least a 3-fold decrease in Ara-C-pretreated cells. This indicated a significant effect of anticancer drugs on the stromal cell line. Using phosphorylated Erk and pRb proteins as cell proliferation markers, we found that phosphorylation of these markers in K562 cells was inhibited during co-cultivation with drug-pretreated stromal cells in MIP-3α-supplemented medium and restored by MIP-3α antibody supplement. In conclusion, anticancer drug pretreatment suppresses the negative control exerted by HS-5 cells on leukemic cell proliferation, via modulation of cytokines in the microenvironment, especially at the level of MIP-3α

PD-L1-specific T cells

DEFF Research Database (Denmark)

Ahmad, Shamaila Munir; Borch, Troels Holz; Hansen, Morten

2016-01-01

-specific T cells that recognize both PD-L1-expressing immune cells and malignant cells. Thus, PD-L1-specific T cells have the ability to modulate adaptive immune reactions by reacting to regulatory cells. Thus, utilization of PD-L1-derived T cell epitopes may represent an attractive vaccination strategy...... for targeting the tumor microenvironment and for boosting the clinical effects of additional anticancer immunotherapy. This review summarizes present information about PD-L1 as a T cell antigen, depicts the initial findings about the function of PD-L1-specific T cells in the adjustment of immune responses...

Membranes replace irradiated blast cells as growth requirement for leukemic blast progenitors in suspension culture

International Nuclear Information System (INIS)

Nara, N.; McCulloch, E.A.

1985-01-01

The blast cells of acute myeloblastic leukemia (AML) may be considered as a renewal population, maintained by blast stem cells capable of both self-renewal and the generation of progeny with reduced or absent proliferative potential. This growth requires that two conditions be met: first, the cultures must contain growth factors in media conditioned either by phytohemagglutinin (PHA)-stimulated mononuclear leukocytes (PHA-LCM), or by cells of the continuous bladder carcinoma line HTB9 (HTB9-CM). Second, the cell density must be maintained at 10(6) blasts/ml; this may be achieved by adding irradiated cells to smaller numbers of intact blasts. The authors are concerned with the mechanism of the feeding function. They present evidence that (a) cell-cell contact is required. (b) Blasts are heterogeneous in respect to their capacity to support growth. (c) Fractions containing membranes from blast cells will substitute for intact cells in promoting the generation of new blast progenitors in culture. (d) This membrane function may be specific for AML blasts, since membranes from blasts of lymphoblastic leukemia or normal marrow cells were inactive

Role of Bruton's tyrosine kinase in B cells and malignancies

NARCIS (Netherlands)

Pal Singh, S. (Simar); F. Dammeijer (Floris); R.W. Hendriks (Rudi)

2018-01-01

textabstractBruton's tyrosine kinase (BTK) is a non-receptor kinase that plays a crucial role in oncogenic signaling that is critical for proliferation and survival of leukemic cells in many B cell malignancies. BTK was initially shown to be defective in the primary immunodeficiency X-linked

A critical role of CDKN3 in Bcr-Abl-mediated tumorigenesis.

Directory of Open Access Journals (Sweden)

Qinghuang Chen

Full Text Available CDKN3 (cyclin-dependent kinase inhibitor 3, a dual specificity protein phosphatase, dephosphorylates cyclin-dependent kinases (CDKs and thus functions as a key negative regulator of cell cycle progression. Deregulation or mutations of CDNK3 have been implicated in various cancers. However, the role of CDKN3 in Bcr-Abl-mediated chronic myelogenous leukemia (CML remains unknown. Here we found that CDKN3 acts as a tumor suppressor in Bcr-Abl-mediated leukemogenesis. Overexpression of CDKN3 sensitized the K562 leukemic cells to imanitib-induced apoptosis and dramatically inhibited K562 xenografted tumor growth in nude mouse model. Ectopic expression of CDKN3 significantly reduced the efficiency of Bcr-Abl-mediated transformation of FDCP1 cells to growth factor independence. In contrast, depletion of CDKN3 expression conferred resistance to imatinib-induced apoptosis in the leukemic cells and accelerated the growth of xenograph leukemia in mice. In addition, we found that CDKN3 mutant (CDKN3-C140S devoid of the phosphatase activity failed to affect the K562 leukemic cell survival and xenografted tumor growth, suggesting that the phosphatase of CDKN3 was required for its tumor suppressor function. Furthermore, we observed that overexpression of CDKN3 reduced the leukemic cell survival by dephosphorylating CDK2, thereby inhibiting CDK2-dependent XIAP expression. Moreover, overexpression of CDKN3 delayed G1/S transition in K562 leukemic cells. Our results highlight the importance of CDKN3 in Bcr-Abl-mediated leukemogenesis, and provide new insights into diagnostics and therapeutics of the leukemia.

Succesful therapy of viral leukemia by transplantation of histocompatibly unmatched marrow

International Nuclear Information System (INIS)

Meredith, R.F.; OKunewick, J.P.; Kuhnert, P.M.; Brozovich, B.J.; Weaver, E.V.

1978-01-01

The therapeutic effectiveness on murine viral-leukemia of allogeneic or hybrid hematopoietic cells transplanted from leukemia-virus resistant donors was evaluated and compared with that of syngeneic cells. Transplantation of syngeneic cells gave no protection to the viral-leukemic mice. Transplantation of spleen cells from allogeneic donors resulted in early deaths of both leukemic and non-leukemic recipients. Transplantation of hybrid spleen cells resulted in no long-term survival of the leukemic mice. However, there were a number of long-term survivors among the leukemic recipients of allogeneic or hybrid marrow cells. Engraftment of allogeneic marrow resulted in a large number of survivors. Hybrid marrow recipients showed an even better survival, but some leukemia relapses. Tests of the longterm survivors revealed that even though they gave no evidence of leukemia they still harbored the active virus. This suggests that the mechanism of protection may be related to some inherent characteristic of the donor cells rendering them refractory to viral transformation. A difference in graft-versus-host (GvH) response between the leukemic and control mice was also found after transplantation of allogeneic cells. While all of the controls died of GvH reaction, none of the leukemic recipients showed severe GvH response, suggesting a possible effect of the leukemia on histocompatibility. No GvH reaction was found with hybrid marrow engraftment, although some of the leukemic recipients reconstituted with F 1 cells did die of leukemic relapse. (author)

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

IL8-CXCR2 pathway inhibition as a therapeutic strategy against MDS and AML stem cells.

Science.gov (United States)

Schinke, Carolina; Giricz, Orsolya; Li, Weijuan; Shastri, Aditi; Gordon, Shanisha; Barreyro, Laura; Barreryo, Laura; Bhagat, Tushar; Bhattacharyya, Sanchari; Ramachandra, Nandini; Bartenstein, Matthias; Pellagatti, Andrea; Boultwood, Jacqueline; Wickrema, Amittha; Yu, Yiting; Will, Britta; Wei, Sheng; Steidl, Ulrich; Verma, Amit

2015-05-14

Acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS) are associated with disease-initiating stem cells that are not eliminated by conventional therapies. Novel therapeutic targets against preleukemic stem cells need to be identified for potentially curative strategies. We conducted parallel transcriptional analysis of highly fractionated stem and progenitor populations in MDS, AML, and control samples and found interleukin 8 (IL8) to be consistently overexpressed in patient samples. The receptor for IL8, CXCR2, was also significantly increased in MDS CD34(+) cells from a large clinical cohort and was predictive of increased transfusion dependence. High CXCR2 expression was also an adverse prognostic factor in The Cancer Genome Atlas AML cohort, further pointing to the critical role of the IL8-CXCR2 axis in AML/MDS. Functionally, CXCR2 inhibition by knockdown and pharmacologic approaches led to a significant reduction in proliferation in several leukemic cell lines and primary MDS/AML samples via induction of G0/G1 cell cycle arrest. Importantly, inhibition of CXCR2 selectively inhibited immature hematopoietic stem cells from MDS/AML samples without an effect on healthy controls. CXCR2 knockdown also impaired leukemic growth in vivo. Together, these studies demonstrate that the IL8 receptor CXCR2 is an adverse prognostic factor in MDS/AML and is a potential therapeutic target against immature leukemic stem cell-enriched cell fractions in MDS and AML. © 2015 by The American Society of Hematology.

FLT3 mutations in early T-cell precursor ALL characterize a stem cell like leukemia and imply the clinical use of tyrosine kinase inhibitors.

Directory of Open Access Journals (Sweden)

Martin Neumann

Full Text Available Early T-cell precursor acute lymphoblastic leukemia (ETP-ALL has been identified as high-risk subgroup of acute T-lymphoblastic leukemia (T-ALL with a high rate of FLT3-mutations in adults. To unravel the underlying pathomechanisms and the clinical course we assessed molecular alterations and clinical characteristics in a large cohort of ETP-ALL (n = 68 in comparison to non-ETP T-ALL adult patients. Interestingly, we found a high rate of FLT3-mutations in ETP-ALL samples (n = 24, 35%. Furthermore, FLT3 mutated ETP-ALL was characterized by a specific immunophenotype (CD2+/CD5-/CD13+/CD33-, a distinct gene expression pattern (aberrant expression of IGFBP7, WT1, GATA3 and mutational status (absence of NOTCH1 mutations and a low frequency, 21%, of clonal TCR rearrangements. The observed low GATA3 expression and high WT1 expression in combination with lack of NOTCH1 mutations and a low rate of TCR rearrangements point to a leukemic transformation at the pluripotent prothymocyte stage in FLT3 mutated ETP-ALL. The clinical outcome in ETP-ALL patients was poor, but encouraging in those patients with allogeneic stem cell transplantation (3-year OS: 74%. To further explore the efficacy of targeted therapies, we demonstrate that T-ALL cell lines transfected with FLT3 expression constructs were particularly sensitive to tyrosine kinase inhibitors. In conclusion, FLT3 mutated ETP-ALL defines a molecular distinct stem cell like leukemic subtype. These data warrant clinical studies with the implementation of FLT3 inhibitors in addition to early allogeneic stem cell transplantation for this high risk subgroup.

Autonomous growth potential of leukemia blast cells is associated with poor prognosis in human acute leukemias

Directory of Open Access Journals (Sweden)

Jakubowski Ann A

2009-12-01

Full Text Available Abstract We have described a severe combined immunodeficiency (SCID mouse model that permits the subcutaneous growth of primary human acute leukemia blast cells into a measurable subcutaneous nodule which may be followed by the development of disseminated disease. Utilizing the SCID mouse model, we examined the growth potential of leukemic blasts from 133 patients with acute leukemia, (67 acute lymphoblastic leukemia (ALL and 66 acute myeloid leukemia (AML in the animals after subcutaneous inoculation without conditioning treatment. The blasts displayed three distinct growth patterns: "aggressive", "indolent", or "no tumor growth". Out of 133 leukemias, 45 (33.8% displayed an aggressive growth pattern, 14 (10.5% displayed an indolent growth pattern and 74 (55.6% did not grow in SCID mice. The growth probability of leukemias from relapsed and/or refractory disease was nearly 3 fold higher than that from patients with newly diagnosed disease. Serial observations found that leukemic blasts from the same individual, which did not initiate tumor growth at initial presentation and/or at early relapse, may engraft and grow in the later stages of disease, suggesting that the ability of leukemia cells for engraftment and proliferation was gradually acquired following the process of leukemia progression. Nine autonomous growing leukemia cell lines were established in vitro. These displayed an aggressive proliferation pattern, suggesting a possible correlation between the capacity of human leukemia cells for autonomous proliferation in vitro and an aggressive growth potential in SCID mice. In addition, we demonstrated that patients whose leukemic blasts displayed an aggressive growth and dissemination pattern in SClD mice had a poor clinical outcome in patients with ALL as well as AML. Patients whose leukemic blasts grew indolently or whose leukemia cells failed to induce growth had a significantly longer DFS and more favorable clinical course.

Bioengineering targeted nanodrugs for hematologic malignancies: An innovation in pediatric oncology

Science.gov (United States)

Krishnan, Vinu

Chemotherapy for pediatric cancers employs combinations of highly toxic drugs. This has achieved 5-year survival rates exceeding 90% in children treated for leukemia -- the most prominent form of pediatric cancer. However, delayed onset of harmful side effects in more than 60% of survivors result in death or low quality of life post therapy. This is primarily due to the non-specific effect of drugs on healthy dividing cells in a growing child. Nanomedicine has advanced tremendously to improve adult cancer therapy, but as yet has had minimal impact in pediatric oncology. There is a pressing need for innovative therapeutic strategies that can reduce life-threatening side effects caused by conventional chemotherapy in the clinic. Targeting chemotherapeutic agents specifically to leukemia cells may alleviate treatment-related toxicity in children. The research objective of this dissertation is to bioengineer and advance preclinically a novel nanotherapeutic approach that can specifically target and deliver drugs into leukemic cells. Dexamethasone (Dex) is one of the most commonly used chemotherapeutic drugs in treating pediatric leukemia. For the first part in this study, we encapsulated Dex in polymeric NPs and validated its anti-leukemic potential in vitro and in vivo. NPs with an average diameter of 110 nm were assembled from an amphiphilic block copolymer of poly(ethylene glycol) (PEG) and poly-caprolactone (PCL) bearing pendant cyclic ketals (ECT2). The blank NPs were nontoxic to cultured cells in vitro and to mice in vivo. Encapsulation of Dex into the NPs (Dex-NP) did not compromise the bioactivity of the drug. Dex-NPs induced glucocorticoid phosphorylation and showed cytotoxicity similar to free drug when treated with leukemic cells. Studies using NPs labeled with fluorescent dyes revealed leukemic cell surface binding and internalization. In vivo biodistribution studies showed NP accumulation in the liver and spleen with subsequent clearance of particles with

Acadesine kills chronic myelogenous leukemia (CML cells through PKC-dependent induction of autophagic cell death.

Directory of Open Access Journals (Sweden)

Guillaume Robert

Full Text Available CML is an hematopoietic stem cell disease characterized by the t(9;22 (q34;q11 translocation encoding the oncoprotein p210BCR-ABL. The effect of acadesine (AICAR, 5-Aminoimidazole-4-carboxamide-1-beta-D-ribofuranoside a compound with known antileukemic effect on B cell chronic lymphoblastic leukemia (B-CLL was investigated in different CML cell lines. Acadesine triggered loss of cell metabolism in K562, LAMA-84 and JURL-MK1 and was also effective in killing imatinib-resistant K562 cells and Ba/F3 cells carrying the T315I-BCR-ABL mutation. The anti-leukemic effect of acadesine did not involve apoptosis but required rather induction of autophagic cell death. AMPK knock-down by Sh-RNA failed to prevent the effect of acadesine, indicating an AMPK-independent mechanism. The effect of acadesine was abrogated by GF109203X and Ro-32-0432, both inhibitor of classical and new PKCs and accordingly, acadesine triggered relocation and activation of several PKC isoforms in K562 cells. In addition, this compound exhibited a potent anti-leukemic effect in clonogenic assays of CML cells in methyl cellulose and in a xenograft model of K562 cells in nude mice. In conclusion, our work identifies an original and unexpected mechanism by which acadesine triggers autophagic cell death through PKC activation. Therefore, in addition to its promising effects in B-CLL, acadesine might also be beneficial for Imatinib-resistant CML patients.

Pulmonary leukemic involvement: high-resolution computed tomography evaluation

International Nuclear Information System (INIS)

Oliveira, Ana Paola de; Marchiori, Edson; Souza Junior, Arthur Soares

2004-01-01

Objective: To evaluate the role of high-resolution computed tomography (HRCT) in patients with leukemia and pulmonary symptoms, to establish the main patterns and to correlate them with the etiology. Materials and Methods: This is a retrospective study of the HRCT of 15 patients with leukemia and pulmonary symptoms. The examinations were performed using a spatial high-resolution protocol and were analyzed by two independent radiologists. Results: The main HRCT patterns found were ground-glass opacity (n=11), consolidation (n=9), airspace nodules (n=3), septal thickening (n=3), tree-in-bud pattern (n=3), and pleural effusion (n=3). Pulmonary infection was the most common finding seen in 12 patients: bacterial pneumonia (n=6), fungal infection (n = 4), pulmonary tuberculosis (n=1) and viral infection (n=1). Leukemic pleural infiltration (n=1), lymphoma (n=1) and pulmonary hemorrhage (n=1) were detected in the other three patients. Conclusion: HRCT is an important tool that may suggest the cause of lung involvement, its extension and in some cases to guide invasive procedures in patients with leukemia. (author)

Enhanced Expression of Anti-CD19 Chimeric Antigen Receptor in piggyBac Transposon-Engineered T Cells

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Daisuke Morita

2018-03-01

Full Text Available Adoptive T cell therapy using chimeric antigen receptor (CAR-modified T cells is a promising cancer immunotherapy. We previously developed a non-viral method of gene transfer into T cells using a piggyBac transposon system to improve the cost-effectiveness of CAR-T cell therapy. Here, we have further improved our technology by a novel culture strategy to increase the transfection efficiency and to reduce the time of T cell manufacturing. Using a CH2CH3-free CD19-specific CAR transposon vector and combining irradiated activated T cells (ATCs as feeder cells and virus-specific T cell receptor (TCR stimulation, we achieved 51.4% ± 14% CAR+ T cells and 2.8-fold expansion after 14 culture days. Expanded CD19.CAR-T cells maintained a significant fraction of CD45RA+CCR7+ T cells and demonstrated potent antitumor activity against CD19+ leukemic cells both in vitro and in vivo. Therefore, piggyBac-based gene transfer may provide an alternative to viral gene transfer for CAR-T cell therapy.

Regulation of Trib2 by an E2F1-C/EBPα feedback loop in AML cell proliferation.

LENUS (Irish Health Repository)

Rishi, Loveena

2014-04-10

The loss of regulation of cell proliferation is a key event in leukemic transformation, and the oncogene tribbles (Trib)2 is emerging as a pivotal target of transcription factors in acute leukemias. Deregulation of the transcription factor E2F1, normally repressed by CCAAT enhancer-binding protein α (C\\/EBPα)-p42, occurs in acute myeloid leukemia (AML), resulting in the perturbation of cell cycle and apoptosis, emphasizing its importance in the molecular pathogenesis of AML. Here we show that E2F family members directly regulate Trib2 in leukemic cells and identify a feedback regulatory loop for E2F1, C\\/EBPα, and Trib2 in AML cell proliferation and survival. Further analyses revealed that E2F1-mediated Trib2 expression was repressed by C\\/EBPα-p42, and in normal granulocyte\\/macrophage progenitor cells, we detect C\\/EBPα bound to the Trib2 promoter. Pharmacological inhibition of the cell cycle or Trib2 knockdown resulted in a block in AML cell proliferation. Our work proposes a novel paradigm whereby E2F1 plays a key role in the regulation of Trib2 expression important for AML cell proliferation control. Importantly, we identify the contribution of dysregulated C\\/EBPα and E2F1 to elevated Trib2 expression and leukemic cell survival, which likely contributes to the initiation and maintenance of AML and may have significant implications for normal and malignant hematopoiesis.

Migration of acute lymphoblastic leukemia cells into human bone marrow stroma.

Science.gov (United States)

Makrynikola, V; Bianchi, A; Bradstock, K; Gottlieb, D; Hewson, J

1994-10-01

Most cases of acute lymphoblastic leukemia (ALL) arise from malignant transformation of B-cell precursors in the bone marrow. Recent studies have shown that normal and leukemic B-cell precursors bind to bone marrow stromal cells through the beta-1 integrins VLA-4 and VLA-5, thereby exposing early lymphoid cells to regulatory cytokines. It has been recently reported that the pre-B cell line NALM-6 is capable of migrating under layers of murine stromal cells in vitro (Miyake et al. J Cell Biol 1992;119:653-662). We have further analyzed leukemic cell motility using human bone marrow fibroblasts (BMF) as a stromal layer. The precursor-B ALL cell line NALM-6 rapidly adhered to BMF, and underwent migration or tunneling into BMF layers within 5 h, as demonstrated by light and electron microscopy, and confirmed by a chromium-labeling assay. Migration was also observed with the precursor-B ALL lines Reh and KM-3, with a T leukemia line RPMI-8402, the monocytic line U937, and the mature B line Daudi. In contrast, mature B (Raji), myeloid (K562, HL-60), and T lines (CCRF-CEM, MOLT-4) did not migrate. When cases of leukemia were analyzed, BMF migration was largely confined to precursor-B ALL, occurring in eight of 13 cases tested. Of other types of leukemia, migration was observed in one of four cases of T-ALL, but no evidence was seen in six acute myeloid leukemias and two patients with chronic lymphocytic leukemia. Only minimal migration into BMF was observed with purified sorted CD10+ CD19+ early B cells from normal adult marrow, while normal mature B lymphocytes from peripheral blood did not migrate. ALL migration was inhibited by monoclonal antibodies to the beta sub-unit of the VLA integrin family, and by a combination of antibodies to VLA-4 and VLA-5. Partial inhibition was also observed when leukemic cells were incubated with antibodies to VLA-4, VLA-5, or VLA-6 alone. In contrast, treatment of stromal cells with antibodies to vascular cell adhesion molecule or

Clinical approach to circumvention of multidrug resistance in refractory leukemic patients: association of cyclosporin A with etoposide.

Science.gov (United States)

Maia, R C; Carriço, M K; Klumb, C E; Noronha, H; Coelho, A M; Vasconcelos, F C; Ruimanek, V M

1997-12-01

Alternative therapy for refractory leukemic patients is being increasingly adopted. Circumvention of multidrug resistance represents a strategy that has been taken into account when conventional chemotherapy failed. In this work a group of 15 refractory, heavily pretreated, patients was enrolled in a circumvention protocol including etoposide (ETO) and cyclosporin A (CSA). All patients received etoposide prior to this schedule. Toxicity to circumvention protocol was acceptable and only one serious side-effect was observed. Two hematological clinical responses were seen, both of which were positive to P-glycoprotein immunostaining and exhibited in vitro modulation by CSA in cultures using the thymidine incorporation assay. Three out of four patients negative for P-glycoprotein achieved a minor response. Three out of six clinical failures were also negative for Pgp immunostaining one of which exhibited sinergistic effect between ETO and CSA. Our study suggests that hematological response to ETO and CSA association can be obtained in intensely pretreated leukemic patients. Several factors may affect the response such as clinical status before this therapy. Additionally, it also suggests that not all CSA effects on the combination ETO-CSA can be attributed to Pgp modulation.

Myeloablative radioimmunotherapies in the conditioning of patients with AML, MDS and multiple myeloma prior to stem cell transplantation; Myeloablative Radioimmuntherapien zur Konditionierung bei Patienten mit AML, MDS und multiplem Myelom vor Stammzelltransplantation

Energy Technology Data Exchange (ETDEWEB)

Buchmann, I. [Abt. fuer Nuklearmedizin, Universitaetsklinik Heidelberg (Germany)

2008-06-15

Aggressive consolidation chemotherapy and hematopoietic stem cell transplantation have improved the prognosis of patients with acute myeloid leukemia (AML), myelodyplastic syndrome (MDS) and multiple myeloma. Nevertheless, only a minor fraction of patients achieve long-term disease-free survival after stem cell transplantation with disease recurrence being the most common cause of treatment failure. In addition, therapy-related effects such as toxicity of chemotherapy and complications of stem cell transplantation increase mortality rates significantly. Myeloablative radioimmunotherapy uses radiolabeled monoclonal antibodies (mAb) with affinity for the hematopoietic marrow. It applies high radiation doses in the bone marrow but spares normal organs. Adding myeloablative radioimmunotherapy to the conditioning schemes of AML, MDS and multiple myeloma before stem cell transplantation allows for the achievement of a pronounced antileukemic/antimyeloma effect for the reduction of relapse rates without significant increase of acute organ toxicity and therapy-related mortality. In order to optimise therapy, a rational design of the nuclide-antibody combination is necessary. {sup 90}Y, {sup 188}Re and {sup 131}I are the most frequently used {beta}{sup -}-particles. Of these, {sup 90}Y is the most qualified nuclide for myeloablation. Backbone stabilised DTPA are ideal chelators to stably conjugate {sup 90}Y to antibodies so far. For myeloablative conditioning, anti-CD66-, -45- and -33-mAb are used. The anti-CD66-antibody BW250/183 binds to normal hematopoietic cells but not to leukemic blasts and myeloma cells. The {sup 90}Y-2B3M-DTPA-BW250/183 is the most suited radioimmunoconjugate for patients with an infiltration grade of leukemic blasts in the bone marrow < 25%. The specific doses (Gy/GBq) are 10.2 {+-} 1.8 (bone marrow), 2.7 {+-} 2 (liver) and < 1 (kidneys). In contrast, radiolabeled anti-CD33- and anti-CD45-antibodies bind to both, most of white blood cells and

Scoulerine affects microtubule structure, inhibits proliferation, arrests cell cycle and thus culminates in the apoptotic death of cancer cells.

Science.gov (United States)

Habartova, Klara; Havelek, Radim; Seifrtova, Martina; Kralovec, Karel; Cahlikova, Lucie; Chlebek, Jakub; Cermakova, Eva; Mazankova, Nadezda; Marikova, Jana; Kunes, Jiri; Novakova, Lucie; Rezacova, Martina

2018-03-19

Scoulerine is an isoquinoline alkaloid, which indicated promising suppression of cancer cells growth. However, the mode of action (MOA) remained unclear. Cytotoxic and antiproliferative properties were determined in this study. Scoulerine reduces the mitochondrial dehydrogenases activity of the evaluated leukemic cells with IC 50 values ranging from 2.7 to 6.5 µM. The xCELLigence system revealed that scoulerine exerted potent antiproliferative activity in lung, ovarian and breast carcinoma cell lines. Jurkat and MOLT-4 leukemic cells treated with scoulerine were decreased in proliferation and viability. Scoulerine acted to inhibit proliferation through inducing G2 or M-phase cell cycle arrest, which correlates well with the observed breakdown of the microtubule network, increased Chk1 Ser345, Chk2 Thr68 and mitotic H3 Ser10 phosphorylation. Scoulerine was able to activate apoptosis, as determined by p53 upregulation, increase caspase activity, Annexin V and TUNEL labeling. Results highlight the potent antiproliferative and proapoptotic function of scoulerine in cancer cells caused by its ability to interfere with the microtubule elements of the cytoskeleton, checkpoint kinase signaling and p53 proteins. This is the first study of the mechanism of scoulerine at cellular and molecular level. Scoulerine is a potent antimitotic compound and that it merits further investigation as an anticancer drug.

Monitoring Tumour Cell Purge by Long Term Marrow Culture in Acute Leukemia

International Nuclear Information System (INIS)

El-Masry, M.; Hashem, T. M.

2001-01-01

Purging of leukemic cells from bone marrow harvested for autologous bone marrow transplantation (ABMT) remains a challenge. This work aimed at evaluating the efficacy of long-term marrow culture (LTMC) on purging leukemic progenitors in acute leukemia. Design and methods: We planned to study the presence of immunoglobulin heavy (lgH) chain gene rearrangements by polymerase chain reaction (PCR) at diagnosis for bone marrow of 23 patients with acute leukemia. LTMC was performed only for patients who showed positive IgH chain gene monoclonality at diagnosis. The efficiency of purge was evaluated by PCR for monoclonal IgH chain gene on weekly basis of LTMC. Results: Of the 23 studied cases, 18 (78.26%) showed positive clonal IgH chain gene at diagnosis. LTMC study showed that 6/]8 (33.33%), 3/18 (16.67%),7/18 (38.89%) and 2/18 (11.11 %) underwent complete purging of the leukemic progenitors at the first, second, third and fourth weeks of culture, respectively. Follow up could be performed for 14 positive ALL cases after induction of remission; 12/14 (85.7%) showed minimal residual disease (MRD) while only two cases did not show MRD. Complete purging of the latter two cases by LTMC occurred on the second and third weeks of culture. Conclusion: LTMC is a useful and successful method for leukemic cell purging. LTMC should be undertaken at initial diagnosis and on an individual basis. Each case should be dealt with solely to determine at which week of culture complete purging could be obtained for subsequent autologous grafting of the purged marrow

The in vivo fate of a 211At labelled monoclonal antibody with known specificity in a murine system

International Nuclear Information System (INIS)

Vaughan, A.T.M.; Bateman, W.J.; Fisher, D.R.

1982-01-01

A monoclonal antibody reactive against the human transferrin receptor has been labelled with the alpha and X ray emitting isotope Astatine 211. The labelling procedure does not affect the ability of the product to bind to the transferrin receptor on the human leukemic cell line HL60. Using a direct binding assay, 211 At labelled antibody can be specifically inhibited from binding to its target cells by excess unlabelled antibody. Furthermore, the binding inhibition demonstrated in this system correlates to enhanced clonogenic survival of these cells, indicating that very few atoms of 211 At/cell are required for cell death. Data obtained from labelled antibody injected into mice show that the labelled product in serum retains the ability to bind to HL60 cells in vitro, although tissue distributions of the injected activity implies that some of the radiolabel is lost from the protein. Despite this loss of label, preliminary experiments on the localization of labelled antibody to HL60 cells growing s/c in nude mice show that tumor tissue has a higher specific activity than all other tissues, other than blood, after 12 hours. This suggests that further work on the nature of label degradation in vivo is warranted in the context of potential therapeutic and diagnostic studies

Sulforaphane induces cell cycle arrest and apoptosis in acute lymphoblastic leukemia cells.

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Koramit Suppipat

Full Text Available Acute lymphoblastic leukemia (ALL is the most common hematological cancer in children. Although risk-adaptive therapy, CNS-directed chemotherapy, and supportive care have improved the survival of ALL patients, disease relapse is still the leading cause of cancer-related death in children. Therefore, new drugs are needed as frontline treatments in high-risk disease and as salvage agents in relapsed ALL. In this study, we report that purified sulforaphane, a natural isothiocyanate found in cruciferous vegetables, has anti-leukemic properties in a broad range of ALL cell lines and primary lymphoblasts from pediatric T-ALL and pre-B ALL patients. The treatment of ALL leukemic cells with sulforaphane resulted in dose-dependent apoptosis and G2/M cell cycle arrest, which was associated with the activation of caspases (3, 8, and 9, inactivation of PARP, p53-independent upregulation of p21(CIP1/WAF1, and inhibition of the Cdc2/Cyclin B1 complex. Interestingly, sulforaphane also inhibited the AKT and mTOR survival pathways in most of the tested cell lines by lowering the levels of both total and phosphorylated proteins. Finally, the administration of sulforaphane to the ALL xenograft models resulted in a reduction of tumor burden, particularly following oral administration, suggesting a potential role as an adjunctive agent to improve the therapeutic response in high-risk ALL patients with activated AKT signaling.

Myeloperoxidase mRNA detection for lineage determination of leukemic blasts: retrospective analysis.

Science.gov (United States)

Crisan, D; Anstett, M J

1995-07-01

Myeloperoxidase (MPO) mRNA is an early myeloid marker; its detection in the morphologically and immunophenotypically primitive blasts of acute undifferentiated leukemia (AUL) establishes myeloid lineage and allows reclassification as acute myelogenous leukemia with minimal differentiation (AML-MO). We have previously reported a procedure for MPO mRNA detection by RT-PCR (reverse transcription-polymerase chain reaction) and an adaptation for use of routine hematology smears. This variant procedure allows retrospective analysis of mRNA and is used in the present study to evaluate the lineage of leukemic blasts in seven cases with morphology and cytochemistry consistent with AUL. All hematology smears used in this study were air-dried, unstained or Wright-stained and stored at room temperature for periods varying between 3 days and 2 years. MPO mRNA was detected in six cases, establishing the myeloid lineage of the blasts and the diagnosis of AML-MO. In the remaining case, the blasts were MPO mRNA negative, confirming the diagnosis of AUL. The RT-PCR procedure for retrospective mRNA analysis is useful in the clinical setting, due to its high specificity and sensitivity, speed (less than 24 h), safety (no radioactivity) and convenient use of routine hematology smears; it is particularly attractive in clinical situations when fresh or frozen specimens are no longer available at the time when the need for molecular diagnostics becomes apparent.

Anti-proliferative and differentiation-inducing activities of the green tea catechin epigallocatechin-3-gallate (EGCG) on the human eosinophilic leukemia EoL-1 cell line.

Science.gov (United States)

Lung, H L; Ip, W K; Wong, C K; Mak, N K; Chen, Z Y; Leung, K N

2002-12-06

A novel approach for the treatment of leukemia is the differentiation therapy in which immature leukemia cells are induced to attain a mature phenotype when exposed to differentiation inducers, either alone or in combinations with other chemotherapeutic or chemopreventive drugs. Over the past decade, numerous studies indicated that green tea catechins (GTC) could suppress the growth and induce apoptosis on a number of human cancer cell lines. However, the differentiation-inducing activity of GTC on human tumors remains poorly understood. In the present study, the effect of the major GTC epigallocatechin-3-gallate (EGCG) on the proliferation and differentiation of a human eosinophilc leukemic cell line, EoL-1, was examined. Our results showed that EGCG suppressed the proliferation of the EoL-1 cells in a dose-dependent manner, with an estimated IC(50) value of 31.5 microM. On the other hand, EGCG at a concentration of 40 microM could trigger the EoL-1 cells to undergo morphological differentiation into mature eosinophil-like cells. Using RT-PCR and flow cytometry, it was found that EGCG upregulated the gene and protein expression of two eosinophil-specific granule proteins, the major basic protein (MBP) and eosinophil peroxidase (EPO), in EoL-1 cells. Taken together, our findings suggest that EGCG can exhibit anti-leukemic activity on a human eosinophilic cell line EoL-1 by suppressing the proliferation and by inducing the differentiation of the leukemia cells.

TLX1 and NOTCH coregulate transcription in T cell acute lymphoblastic leukemia cells

OpenAIRE

Riz, Irene; Hawley, Teresa S; Luu, Truong V; Lee, Norman H; Hawley, Robert G

2010-01-01

Abstract Background The homeobox gene TLX1 (for T-cell leukemia homeobox 1, previously known as HOX11) is inappropriately expressed in a major subgroup of T cell acute lymphoblastic leukemia (T-ALL) where it is strongly associated with activating NOTCH1 mutations. Despite the recognition that these genetic lesions cooperate in leukemogenesis, there have been no mechanistic studies addressing how TLX1 and NOTCH1 functionally interact to promote the leukemic phenotype. Results Global gene expre...

Notch 1 as a potential therapeutic target in cutaneous T-cell lymphoma

DEFF Research Database (Denmark)

Kamstrup, Maria Rørbæk; Gjerdrum, Lise Mette Rahbek; Biskup, Edyta Urszula

2010-01-01

Deregulation of Notch signaling has been linked to the development of T-cell leukemias and several solid malignancies. Yet, it is unknown whether Notch signalling is involved in the pathogenesis of mycosis fungoides and Sezary syndrome, the most common subtypes of cutaneous T cell lymphoma....... By immunohistochemistry of 40 biopsies taken from skin lesions of mycosis fungoides and Sezary syndrome we demonstrated prominent expression of Notch1 on tumor cells, especially in the more advanced stages. The gamma-secretase inhibitor I blocked Notch signaling and potently induced apoptosis in cell lines derived from...... mycosis fungoides (MyLa) and Sezary syndrome (SeAx, HuT-78)and in primary leukemic Sézary cells. Specific downregulation of Notch1 (but not Notch2 and Notch3) by siRNA induced apoptosis in SeAx. The mechanism of apoptosis involved the inhibition of NF-kappaB, which is the most important prosurvival...

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

Science.gov (United States)

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.

T-helper cell-mediated proliferation and cytokine responses against recombinant Merkel cell polyomavirus-like particles.

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Arun Kumar

Full Text Available The newly discovered Merkel Cell Polyomavirus (MCPyV resides in approximately 80% of Merkel cell carcinomas (MCC. Causal role of MCPyV for this rare and aggressive skin cancer is suggested by monoclonal integration and truncation of large T (LT viral antigen in MCC cells. The mutated MCPyV has recently been found in highly purified leukemic cells from patients with chronic lymphocytic leukemia (CLL, suggesting a pathogenic role also in CLL. About 50-80% of adults display MCPyV-specific antibodies. The humoral immunity does not protect against the development of MCC, as neutralizing MCPyV antibodies occur in higher levels among MCC patients than healthy controls. Impaired T-cell immunity has been linked with aggressive MCC behavior. Therefore, cellular immunity appears to be important in MCPyV infection surveillance. In order to elucidate the role of MCPyV-specific Th-cell immunity, peripheral blood mononuclear cells (PBMC of healthy adults were stimulated with MCPyV VP1 virus-like particles (VLPs, using human bocavirus (HBoV VLPs and Candida albicans antigen as positive controls. Proliferation, IFN-γ, IL-13 and IL-10 responses were examined in 15 MCPyV-seropositive and 15 seronegative volunteers. With the MCPyV antigen, significantly stronger Th-cell responses were found in MCPyV-seropositive than MCPyV-seronegative subjects, whereas with the control antigens, the responses were statistically similar. The most readily detectable cytokine was IFN-γ. The MCPyV antigen tended to induce stronger IFN-γ responses than HBoV VLP antigen. Taken together, MCPyV-specific Th-cells elicit vigorous IFN-γ responses. IFN-γ being a cytokine with major antiviral and tumor suppressing functions, Th-cells are suggested to be important mediators of MCPyV-specific immune surveillance.

Cdc42-mediated tubulogenesis controls cell specification

DEFF Research Database (Denmark)

Kesavan, Gokul; Sand, Fredrik Wolfhagen; Greiner, Thomas Uwe

2009-01-01

Understanding how cells polarize and coordinate tubulogenesis during organ formation is a central question in biology. Tubulogenesis often coincides with cell-lineage specification during organ development. Hence, an elementary question is whether these two processes are independently controlled......, or whether proper cell specification depends on formation of tubes. To address these fundamental questions, we have studied the functional role of Cdc42 in pancreatic tubulogenesis. We present evidence that Cdc42 is essential for tube formation, specifically for initiating microlumen formation and later...... for maintaining apical cell polarity. Finally, we show that Cdc42 controls cell specification non-cell-autonomously by providing the correct microenvironment for proper control of cell-fate choices of multipotent progenitors. For a video summary of this article, see the PaperFlick file with the Supplemental Data...

Cell-specific targeting by heterobivalent ligands.

Science.gov (United States)

Josan, Jatinder S; Handl, Heather L; Sankaranarayanan, Rajesh; Xu, Liping; Lynch, Ronald M; Vagner, Josef; Mash, Eugene A; Hruby, Victor J; Gillies, Robert J

2011-07-20

Current cancer therapies exploit either differential metabolism or targeting to specific individual gene products that are overexpressed in aberrant cells. The work described herein proposes an alternative approach--to specifically target combinations of cell-surface receptors using heteromultivalent ligands ("receptor combination approach"). As a proof-of-concept that functionally unrelated receptors can be noncovalently cross-linked with high avidity and specificity, a series of heterobivalent ligands (htBVLs) were constructed from analogues of the melanocortin peptide ligand ([Nle(4), dPhe(7)]-α-MSH) and the cholecystokinin peptide ligand (CCK-8). Binding of these ligands to cells expressing the human Melanocortin-4 receptor and the Cholecystokinin-2 receptor was analyzed. The MSH(7) and CCK(6) were tethered with linkers of varying rigidity and length, constructed from natural and/or synthetic building blocks. Modeling data suggest that a linker length of 20-50 Å is needed to simultaneously bind these two different G-protein coupled receptors (GPCRs). These ligands exhibited up to 24-fold enhancement in binding affinity to cells that expressed both (bivalent binding), compared to cells with only one (monovalent binding) of the cognate receptors. The htBVLs had up to 50-fold higher affinity than that of a monomeric CCK ligand, i.e., Ac-CCK(6)-NH(2). Cell-surface targeting of these two cell types with labeled heteromultivalent ligand demonstrated high avidity and specificity, thereby validating the receptor combination approach. This ability to noncovalently cross-link heterologous receptors and target individual cells using a receptor combination approach opens up new possibilities for specific cell targeting in vivo for therapy or imaging.

Cannabidiol Reduces Leukemic Cell Size ? But Is It Important?

OpenAIRE

Kalenderoglou, Nikoletta; Macpherson, Tara; Wright, Karen L.

2017-01-01

The anti-cancer effect of the plant-derived cannabinoid, cannabidiol, has been widely demonstrated both in vivo and in vitro. However, this body of preclinical work has not been translated into clinical use. Key issues around this failure can be related to narrow dose effects, the cell model used and incomplete efficacy. A model of acute lymphoblastic disease, the Jurkat T cell line, has been used extensively to study the cannabinoid system in the immune system and cannabinoid-induced apoptos...

Regulation of Trib2 by an E2F1-C/EBPα feedback loop in AML cell proliferation

DEFF Research Database (Denmark)

Rishi, Loveena; Hannon, Maura; Salomè, Mara

2014-01-01

α (C/EBPα)-p42, occurs in acute myeloid leukemia (AML), resulting in the perturbation of cell cycle and apoptosis, emphasizing its importance in the molecular pathogenesis of AML. Here we show that E2F family members directly regulate Trib2 in leukemic cells and identify a feedback regulatory loop......The loss of regulation of cell proliferation is a key event in leukemic transformation, and the oncogene tribbles (Trib)2 is emerging as a pivotal target of transcription factors in acute leukemias. Deregulation of the transcription factor E2F1, normally repressed by CCAAT enhancer-binding protein...... for E2F1, C/EBPα, and Trib2 in AML cell proliferation and survival. Further analyses revealed that E2F1-mediated Trib2 expression was repressed by C/EBPα-p42, and in normal granulocyte/macrophage progenitor cells, we detect C/EBPα bound to the Trib2 promoter. Pharmacological inhibition of the cell cycle...

Inhibitin: a specific inhibitor of sodium/sodium exchange in erythrocytes.

OpenAIRE

Morgan, K; Brown, R C; Spurlock, G; Southgate, K; Mir, M A

1986-01-01

An inhibitor of ouabain-insensitive sodium/sodium exchange in erythrocytes has been isolated from leukemic promyelocytes. To explore the specific effects of this inhibitor, named inhibitin, sodium transport experiments were carried out in human erythrocytes. Inhibitin reduced ouabain-insensitive bidirectional sodium transport. It did not change net sodium fluxes, had no significant effect on rubidium influx, and did not inhibit sodium-potassium-ATPase activity. The inhibitory effect of inhibi...

Osteoblasts Protect AML Cells from SDF-1-Induced Apoptosis

Science.gov (United States)

Kremer, Kimberly N.; Dudakovic, Amel; McGee-Lawrence, Meghan E.; Philips, Rachael L.; Hess, Allan D.; Smith, B. Douglas; van Wijnen, Andre J.; Karp, Judith E.; Kaufmann, Scott H.; Westendorf, Jennifer J.; Hedin, Karen E.

2014-01-01

The bone marrow provides a protective environment for acute myeloid leukemia (AML) cells that often allows leukemic stem cells to survive standard chemotherapeutic regimens. Targeting these leukemic stem cells within the bone marrow is critical for preventing relapse. We recently demonstrated that SDF-1, a chemokine abundant in the bone marrow, induces apoptosis in AML cell lines and in patient samples expressing high levels of its receptor, CXCR4. Here we show that a subset of osteoblast lineage cells within the bone marrow can protect AML cells from undergoing apoptosis in response to the SDF-1 naturally present in that location. In co-culture systems, osteoblasts at various stages of differentiation protected AML cell lines and patient isolates from SDF-1-induced apoptosis. The differentiation of the osteoblast cell lines, MC3T3 and W-20-17, mediated this protection via a cell contact-independent mechanism. In contrast, bone marrow-derived mesenchymal cells, the precursors of osteoblasts, induced apoptosis in AML cells via a CXCR4-dependent mechanism and failed to protect AML cells from exogenously added SDF-1. These results indicate that osteoblasts in the process of differentiation potently inhibit the SDF-1-driven apoptotic pathway of CXCR4-expressing AML cells residing in the bone marrow. Drugs targeting this protective mechanism could potentially provide a new approach to treating AML by enhancing the SDF-1-induced apoptosis of AML cells residing within the bone marrow microenvironment. PMID:24851270

C/EBPα is dispensable for the ontogeny of PD-1+ CD4+ memory T cells but restricts their expansion in an age-dependent manner

DEFF Research Database (Denmark)

Norrie, Ida Christine; Ohlsson, Ewa; Nielsen, Olaf

2014-01-01

Ageing and cancer is often associated with altered T cell distributions and this phenomenon has been suggested to be the main driver in the development of immunosenescence. Memory phenotype PD-1+ CD4+ T cells accumulate with age and during leukemic development, and they might account for the atte......Ageing and cancer is often associated with altered T cell distributions and this phenomenon has been suggested to be the main driver in the development of immunosenescence. Memory phenotype PD-1+ CD4+ T cells accumulate with age and during leukemic development, and they might account...... for the attenuated T cell response in elderly or diseased individuals. The transcription factor C/EBPα has been suggested to be responsible for the accumulation as well as for the senescent features of these cells including impaired TCR signaling and decreased proliferation. Thus modulating the activity of C...

Mesenchymal Stromal Cells Can Regulate the Immune Response in the Tumor Microenvironment

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Alessandro Poggi

2016-11-01

Full Text Available The tumor microenvironment is a good target for therapy in solid tumors and hematological malignancies. Indeed, solid tumor cells’ growth and expansion can influence neighboring cells’ behavior, leading to a modulation of mesenchymal stromal cell (MSC activities and remodeling of extracellular matrix components. This leads to an altered microenvironment, where reparative mechanisms, in the presence of sub-acute inflammation, are not able to reconstitute healthy tissue. Carcinoma cells can undergo epithelial mesenchymal transition (EMT, a key step to generate metastasis; these mesenchymal-like cells display the functional behavior of MSC. Furthermore, MSC can support the survival and growth of leukemic cells within bone marrow participating in the leukemic cell niche. Notably, MSC can inhibit the anti-tumor immune response through either carcinoma-associated fibroblasts or bone marrow stromal cells. Experimental data have indicated their relevance in regulating cytolytic effector lymphocytes of the innate and adaptive arms of the immune system. Herein, we will discuss some of the evidence in hematological malignancies and solid tumors. In particular, we will focus our attention on the means by which it is conceivable to inhibit MSC-mediated immune suppression and trigger anti-tumor innate immunity.

MicroRNA-29b mediates altered innate immune development in acute leukemia

Science.gov (United States)

Mundy-Bosse, Bethany L.; Scoville, Steven D.; Chen, Li; McConnell, Kathleen; Mao, Hsiaoyin C.; Ahmed, Elshafa H.; Zorko, Nicholas; Harvey, Sophia; Cole, Jordan; Zhang, Xiaoli; Costinean, Stefan; Croce, Carlo M.; Larkin, Karilyn; Byrd, John C.; Vasu, Sumithira; Blum, William; Yu, Jianhua; Freud, Aharon G.; Caligiuri, Michael A.

2016-01-01

Natural killer (NK) cells can have potent antileukemic activity following haplo-mismatched, T cell–depleted stem cell transplantations for the treatment of acute myeloid leukemia (AML), but they are not successful in eradicating de novo AML. Here, we have used a mouse model of de novo AML to elucidate the mechanisms by which AML evades NK cell surveillance. NK cells in leukemic mice displayed a marked reduction in the cytolytic granules perforin and granzyme B. Further, as AML progressed, we noted the selective loss of an immature subset of NK cells in leukemic mice and in AML patients. This absence was not due to elimination by cell death or selective reduction in proliferation, but rather to the result of a block in NK cell differentiation. Indeed, NK cells from leukemic mice and humans with AML showed lower levels of TBET and EOMES, transcription factors that are critical for terminal NK cell differentiation. Further, the microRNA miR-29b, a regulator of T-bet and EOMES, was elevated in leukemic NK cells. Finally, deletion of miR-29b in NK cells reversed the depletion of this NK cell subset in leukemic mice. These results indicate that leukemic evasion of NK cell surveillance occurs through miR-mediated dysregulation of lymphocyte development, representing an additional mechanism of immune escape in cancer. PMID:27775550

Discrete dynamic modeling of T cell survival signaling networks

Science.gov (United States)

Zhang, Ranran

2009-03-01

Biochemistry-based frameworks are often not applicable for the modeling of heterogeneous regulatory systems that are sparsely documented in terms of quantitative information. As an alternative, qualitative models assuming a small set of discrete states are gaining acceptance. This talk will present a discrete dynamic model of the signaling network responsible for the survival and long-term competence of cytotoxic T cells in the blood cancer T-LGL leukemia. We integrated the signaling pathways involved in normal T cell activation and the known deregulations of survival signaling in leukemic T-LGL, and formulated the regulation of each network element as a Boolean (logic) rule. Our model suggests that the persistence of two signals is sufficient to reproduce all known deregulations in leukemic T-LGL. It also indicates the nodes whose inactivity is necessary and sufficient for the reversal of the T-LGL state. We have experimentally validated several model predictions, including: (i) Inhibiting PDGF signaling induces apoptosis in leukemic T-LGL. (ii) Sphingosine kinase 1 and NFκB are essential for the long-term survival of T cells in T-LGL leukemia. (iii) T box expressed in T cells (T-bet) is constitutively activated in the T-LGL state. The model has identified potential therapeutic targets for T-LGL leukemia and can be used for generating long-term competent CTL necessary for tumor and cancer vaccine development. The success of this model, and of other discrete dynamic models, suggests that the organization of signaling networks has an determining role in their dynamics. Reference: R. Zhang, M. V. Shah, J. Yang, S. B. Nyland, X. Liu, J. K. Yun, R. Albert, T. P. Loughran, Jr., Network Model of Survival Signaling in LGL Leukemia, PNAS 105, 16308-16313 (2008).

Diethylglyoxal bis(guanylhydrazone), a potent inhibitor of mammalian S-adenosylmethionine decarboxylase. Effects on cell proliferation and polyamine metabolism in L1210 leukemia cells.

Science.gov (United States)

Svensson, F; Kockum, I; Persson, L

1993-07-21

The polyamines are cell constituents essential for growth and differentiation. S-Adenosylmethionine decarboxylase (AdoMetDC) catalyzes a key step in the polyamine biosynthetic pathway. Methylglyoxal bis(guanylhydrazone) (MGBG) is an anti-leukemic agent with a strong inhibitory effect against AdoMetDC. However, the lack of specificity limits the usefulness of MGBG. In the present report we have used an analog of MGBG, diethylglyoxal bis(guanylhydrazone) (DEGBG), with a much greater specificity and potency against AdoMetDC, to investigate the effects of AdoMetDC inhibition on cell proliferation and polyamine metabolism in mouse L1210 leukemia cells. DEGBG was shown to effectively inhibit AdoMetDC activity in exponentially growing L1210 cells. The inhibition of AdoMetDC was reflected in a marked decrease in the cellular concentrations of spermidine and spermine. The concentration of putrescine, on the other hand, was greatly increased. Treatment with DEGBG resulted in a compensatory increase in the synthesis of AdoMetDC demonstrating an efficient feedback control. Cells seeded in the presence of DEGBG ceased to grow after a lag period of 1-2 days, indicating that the cells contained an excess of polyamines which were sufficient for one or two cell cycles in the absence of polyamine synthesis. The present results indicate that analogs of MGBG, having a greater specificity against AdoMetDC, might be valuable for studies concerning polyamines and cell proliferation.

Siglec-7 tetramers characterize B-cell subpopulations and leukemic blasts.

Science.gov (United States)

Gieseke, Friederike; Mang, Philippa; Viebahn, Susanne; Sonntag, Inga; Kruchen, Anne; Erbacher, Annika; Pfeiffer, Matthias; Handgretinger, Rupert; Müller, Ingo

2012-08-01

Cell surface glycosylation has important regulatory functions in the maturation, activation, and homeostasis of lymphocytes. The family of human sialic acid-binding immunoglobulin-like lectins (siglecs) comprises inhibitory as well as activating receptors intimately involved in the regulation of immune responses. Analyses of the interaction between siglecs and glycans are hampered by the low affinity of this interaction. Therefore, we expressed siglec-7 in eukaryotic cells, allowing for glycosylation, and oligomerized the protein in analogy to MHC tetramers. Using this tool, flow cytometric analysis of lymphocytes became possible. Sialic acid-dependent binding of siglec-7 tetramers was confirmed by glycan array analysis and loss of siglec tetramer binding after neuraminidase treatment of lymphocytes. In contrast to most lymphocyte subpopulations, which showed high siglec-7 ligand expression, B-cell subpopulations could be further subdivided according to different siglec-7 ligand expression levels. We also analyzed blasts from acute lymphoblastic leukemias of the B-cell lineage as well as the T-cell lineage, since malignant transformation is often associated with aberrant cell surface glycosylation. While pediatric T-ALL blasts highly expressed siglec-7 ligands, siglec-7 ligands were barely detectable on cALL blasts. Taken together, oligomerization of recombinant soluble siglec-7 enabled flow cytometric identification of physiologic lymphocyte subpopulations and malignant blasts. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

SB225002 Induces Cell Death and Cell Cycle Arrest in Acute Lymphoblastic Leukemia Cells through the Activation of GLIPR1

Science.gov (United States)

Leal, Paulo C.; Bhasin, Manoj K.; Zenatti, Priscila Pini; Nunes, Ricardo J.; Yunes, Rosendo A.; Nowill, Alexandre E.; Libermann, Towia A.; Zerbini, Luiz Fernando; Yunes, José Andrés

2015-01-01

Acute Lymphoblastic Leukemia (ALL) is the most frequent childhood malignancy. In the effort to find new anti-leukemic agents, we evaluated the small drug SB225002 (N-(2-hydroxy-4-nitrophenyl)-N’-(2-bromophenyl)urea). Although initially described as a selective antagonist of CXCR2, later studies have identified other cellular targets for SB225002, with potential medicinal use in cancer. We found that SB225002 has a significant pro-apoptotic effect against both B- and T-ALL cell lines. Cell cycle analysis demonstrated that treatment with SB225002 induces G2-M cell cycle arrest. Transcriptional profiling revealed that SB225002-mediated apoptosis triggered a transcriptional program typical of tubulin binding agents. Network analysis revealed the activation of genes linked to the JUN and p53 pathways and inhibition of genes linked to the TNF pathway. Early cellular effects activated by SB225002 included the up-regulation of GLIPR1, a p53-target gene shown to have pro-apoptotic activities in prostate and bladder cancer. Silencing of GLIPR1 in B- and T-ALL cell lines resulted in increased resistance to SB225002. Although SB225002 promoted ROS increase in ALL cells, antioxidant N-Acetyl Cysteine pre-treatment only modestly attenuated cell death, implying that the pro-apoptotic effects of SB225002 are not exclusively mediated by ROS. Moreover, GLIPR1 silencing resulted in increased ROS levels both in untreated and SB225002-treated cells. In conclusion, SB225002 induces cell cycle arrest and apoptosis in different B- and T-ALL cell lines. Inhibition of tubulin function with concurrent activation of the p53 pathway, in particular, its downstream target GLIPR1, seems to underlie the anti-leukemic effect of SB225002. PMID:26302043

Uptake of cerium oxide nanoparticles and its influence on functions of mouse leukemic monocyte macrophages

Energy Technology Data Exchange (ETDEWEB)

Zhou, Xiangyan; Wang, Bing; Jiang, Pengfei; Chen, Yiqi; Mao, Zhengwei, E-mail: zwmao@zju.edu.cn; Gao, Changyou [Zhejiang University, MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering (China)

2015-01-15

Exposure of the CeO{sub 2} nanoparticles (NPs) causes a public concern on their potential health risk due to their wide applications in the fields of fuel additive, commodities, pharmaceutical, and other industries. In this study, the interactions between two commercial CeO{sub 2} NPs (D-CeO{sub 2} from Degussa and PC-CeO{sub 2} from PlasmaChem) and mouse leukemic monocyte macrophage Raw264.7 cells were investigated to provide a fast and in-depth understanding of the biological influences of the NPs. Both types of the CeO{sub 2} NPs had a negative surface charge around −12 mV and showed a tendency to form aggregates with sizes of 191 ± 5.9 and 60.9 ± 2.8 nm in cell culture environment, respectively. The cellular uptake of the CeO{sub 2} NPs increased along with the increase of feeding dosage and prolongation of the culture time. The PC-CeO{sub 2} NPs had a faster uptake rate and reached higher cellular loading amount at the highest feeding concentration (200 µg/mL). In general, both types of the CeO{sub 2} NPs had rather small cytotoxicity even with a dosage as high as 200 µg/mL. The D-CeO{sub 2} NPs showed a relative stronger cytotoxicity especially at higher concentrations and longer incubation time. The NPs were dispersed in vacuoles (most likely endosomes and lysosomes) and cytoplasm. Although both types of the CeO{sub 2} NPs could suppress the production of reactive oxygen species, they impaired the mitochondria membrane potential to some extent. The cytoskeleton organization was altered and consequently the cell adhesion ability decreased after uptake of both types of the CeO{sub 2} NPs.

Shedding of CD9 antigen into cerebrospinal fluid by acute lymphoblastic leukemia cells.

Science.gov (United States)

Komada, Y; Ochiai, H; Shimizu, K; Azuma, E; Kamiya, H; Sakurai, M

1990-07-01

The accurate identification of small numbers of leukemic cells in the cerebrospinal fluid (CSF) presents a diagnostic problem in the treatment of acute lymphoblastic leukemia (ALL). We demonstrated that soluble CD9 antigen was shed into CSF obtained from children with ALL, using enzyme-linked immunosorbent assay (ELISA), which used the activity of CD9 antigen to bind the Ricinus communis agglutinin (RCA1) and a monoclonal antibody, SJ-9A4, simultaneously. Using RCA1/SJ-9A4 ELISA, CD9 antigen was detectable in CSF but not in plasma from 12 cases of CD9+ ALL in central nervous system (CNS) relapse. However, CD9 antigen was not released into CSF from 11 cases of CD9- ALL with CNS involvement, 136 cases of CD9+ ALL in complete remission (CR), 29 cases of CD9- ALL in CR, or 21 cases of aseptic meningitis. Interestingly, the levels of CD9 antigen were elevated in CSF from 7 of 10 CD9+ ALL patients without cytologically proven CNS involvement at diagnosis, with subsequent return to undetectable levels after initial induction chemotherapy was begun. In addition, sequential analysis of CSF from a 5-year-old boy with CD9+ ALL in CNS relapse showed that levels of CD9 antigen correlated well with the number of leukemic cells in CSF. Serial quantitative analysis of CD9 antigen in CSF could be useful to detect the proliferation of residual leukemic cells before the clinical manifestation.

SphK1 inhibitor II (SKI-II) inhibits acute myelogenous leukemia cell growth in vitro and in vivo

International Nuclear Information System (INIS)

Yang, Li; Weng, Wei; Sun, Zhi-Xin; Fu, Xian-Jie; Ma, Jun; Zhuang, Wen-Fang

2015-01-01

Previous studies have identified sphingosine kinase 1 (SphK1) as a potential drug target for treatment of acute myeloid leukemia (AML). In the current study, we investigated the potential anti-leukemic activity of a novel and specific SphK1 inhibitor, SKI-II. We demonstrated that SKI-II inhibited growth and survival of human AML cell lines (HL-60 and U937 cells). SKI-II was more efficient than two known SphK1 inhibitors SK1-I and FTY720 in inhibiting AML cells. Meanwhile, it induced dramatic apoptosis in above AML cells, and the cytotoxicity by SKI-II was almost reversed by the general caspase inhibitor z-VAD-fmk. SKI-II treatment inhibited SphK1 activation, and concomitantly increased level of sphingosine-1-phosphate (S1P) precursor ceramide in AML cells. Conversely, exogenously-added S1P protected against SKI-II-induced cytotoxicity, while cell permeable short-chain ceramide (C6) aggravated SKI-II's lethality against AML cells. Notably, SKI-II induced potent apoptotic death in primary human AML cells, but was generally safe to the human peripheral blood mononuclear cells (PBMCs) isolated from healthy donors. In vivo, SKI-II administration suppressed growth of U937 leukemic xenograft tumors in severe combined immunodeficient (SCID) mice. These results suggest that SKI-II might be further investigated as a promising anti-AML agent. - Highlights: • SKI-II inhibits proliferation and survival of primary and transformed AML cells. • SKI-II induces apoptotic death of AML cells, but is safe to normal PBMCs. • SKI-II is more efficient than two known SphK1 inhibitors in inhibiting AML cells. • SKI-II inhibits SphK1 activity, while increasing ceramide production in AML cells. • SKI-II dose-dependently inhibits U937 xenograft growth in SCID mice

SphK1 inhibitor II (SKI-II) inhibits acute myelogenous leukemia cell growth in vitro and in vivo

Energy Technology Data Exchange (ETDEWEB)

Yang, Li; Weng, Wei; Sun, Zhi-Xin; Fu, Xian-Jie; Ma, Jun, E-mail: majuntongrensh1@126.com; Zhuang, Wen-Fang, E-mail: wenfangzhuangmd@163.com

2015-05-15

Previous studies have identified sphingosine kinase 1 (SphK1) as a potential drug target for treatment of acute myeloid leukemia (AML). In the current study, we investigated the potential anti-leukemic activity of a novel and specific SphK1 inhibitor, SKI-II. We demonstrated that SKI-II inhibited growth and survival of human AML cell lines (HL-60 and U937 cells). SKI-II was more efficient than two known SphK1 inhibitors SK1-I and FTY720 in inhibiting AML cells. Meanwhile, it induced dramatic apoptosis in above AML cells, and the cytotoxicity by SKI-II was almost reversed by the general caspase inhibitor z-VAD-fmk. SKI-II treatment inhibited SphK1 activation, and concomitantly increased level of sphingosine-1-phosphate (S1P) precursor ceramide in AML cells. Conversely, exogenously-added S1P protected against SKI-II-induced cytotoxicity, while cell permeable short-chain ceramide (C6) aggravated SKI-II's lethality against AML cells. Notably, SKI-II induced potent apoptotic death in primary human AML cells, but was generally safe to the human peripheral blood mononuclear cells (PBMCs) isolated from healthy donors. In vivo, SKI-II administration suppressed growth of U937 leukemic xenograft tumors in severe combined immunodeficient (SCID) mice. These results suggest that SKI-II might be further investigated as a promising anti-AML agent. - Highlights: • SKI-II inhibits proliferation and survival of primary and transformed AML cells. • SKI-II induces apoptotic death of AML cells, but is safe to normal PBMCs. • SKI-II is more efficient than two known SphK1 inhibitors in inhibiting AML cells. • SKI-II inhibits SphK1 activity, while increasing ceramide production in AML cells. • SKI-II dose-dependently inhibits U937 xenograft growth in SCID mice.

The acute monocytic leukemias: multidisciplinary studies in 45 patients.

Science.gov (United States)

Straus, D J; Mertelsmann, R; Koziner, B; McKenzie, S; de Harven, E; Arlin, Z A; Kempin, S; Broxmeyer, H; Moore, M A; Menendez-Botet, C J; Gee, T S; Clarkson, B D

1980-11-01

The clinical and laboratory features of 37 patients with variants of acute monocytic leukemia are described. Three of these 37 patients who had extensive extramedullary leukemic tissue infiltration are examples of true histiocytic "lymphomas." Three additional patients with undifferentiated leukemias, one patient with refractory anemia with excess of blasts, one patient with chronic myelomonocytic leukemia, one patient with B-lymphocyte diffuse "histiocytic" lymphoma and one patient with "null" cell, terminal deoxynucleotidyl transferase-positive lymphoblastic lymphoma had bone marrow cells with monocytic features. Another patient had dual populations of lymphoid and monocytoid leukemic cells. The true monocytic leukemias, acute monocytic leukemia (AMOL) and acute myelomonocytic leukemia (AMMOL), are closely related to acute myelocytic leukemia (AML) morphologically and by their response to chemotherapy. like AML, the leukemic cells from the AMMOL and AMOL patients form leukemic clusters in semisolid media. Cytochemical staining of leukemic cells for nonspecific esterases, presence of Fc receptor on the cell surface, phagocytic ability, low TdT activity, presence of surface "ruffles" and "ridges" on scanning EM, elevations of serum lysozyme, and clinical manifestations of leukemic tissue infiltration are features which accompanied monocytic differentiation in these cases.

Towards The Generation of Functionalized Magnetic Nanowires to Target Leukemic Cells

KAUST Repository

Alsharif, Nouf

2016-01-01

. In addition the NWs can be coated and functionalized to target cells of interest and, upon exposure to an alternating magnetic field, have been shown to induce cell death on several types of adherent cells, including several cancer cell types. For suspension

In Vitro Production of Echioidinin, 7-O-Methywogonin from Callus Cultures of Andrographis lineata and Their Cytotoxicity on Cancer Cells.

Directory of Open Access Journals (Sweden)

Arifullah Mohammed

Full Text Available Andrographis lineata is an herbal medicinal plant used in traditional medicine as a substitute for Andrographis paniculata. Here, using mature leaf explants of A. lineata we demonstrate for the first time the callus induction established on MS medium containing 1.0 mg l-1 IAA. Dried callus was subjected to solvent extraction with acetone. Further the acetone residue was separated by silica gel column chromatography, crystallized and characterized on the basis of nuclear magnetic resonance (proton and c13 and liquid chromatographic mass spectroscopy. This analysis revealed the occurrence of two known flavones namely, 7-O-methylwogonin (MW and Echioidinin (ED. Furthermore, these compounds were tested for their cytotoxicity against leukemic cell line, CEM. We identify that ED and MW induced cytotoxicity in a time- and concentration-dependent manner. Further increase in the LDH release upon treatment with ED and MW further confirmed our cytotoxicity results against leukemic cell line. Strikingly, MW was more potent than ED when compared by trypan blue and MTT assays. Our results recapitulate the utility of callus cultures for the production of plant specific bioactive secondary metabolites instead of using wild plants. Together, our in vitro studies provide new insights of A. lineata callus cultures serving as a source for cancer chemotherapeutic agents.

In Vitro Production of Echioidinin, 7-O-Methywogonin from Callus Cultures of Andrographis lineata and Their Cytotoxicity on Cancer Cells

Science.gov (United States)

Mohammed, Arifullah; Chiruvella, Kishore K.; Rao, Yerra Koteswara; Geethangili, Madamanchi; Raghavan, Sathees C.; Ghanta, Rama Gopal

2015-01-01

Andrographis lineata is an herbal medicinal plant used in traditional medicine as a substitute for Andrographis paniculata. Here, using mature leaf explants of A. lineata we demonstrate for the first time the callus induction established on MS medium containing 1.0 mg l–1 IAA. Dried callus was subjected to solvent extraction with acetone. Further the acetone residue was separated by silica gel column chromatography, crystallized and characterized on the basis of nuclear magnetic resonance (proton and c13) and liquid chromatographic mass spectroscopy. This analysis revealed the occurrence of two known flavones namely, 7-O-methylwogonin (MW) and Echioidinin (ED). Furthermore, these compounds were tested for their cytotoxicity against leukemic cell line, CEM. We identify that ED and MW induced cytotoxicity in a time- and concentration-dependent manner. Further increase in the LDH release upon treatment with ED and MW further confirmed our cytotoxicity results against leukemic cell line. Strikingly, MW was more potent than ED when compared by trypan blue and MTT assays. Our results recapitulate the utility of callus cultures for the production of plant specific bioactive secondary metabolites instead of using wild plants. Together, our in vitro studies provide new insights of A. lineata callus cultures serving as a source for cancer chemotherapeutic agents. PMID:26488879

The role of C/EBPa in PD-1+ CD4+ T cells & modulation of RNR activity prolongs survival of mice with AML

DEFF Research Database (Denmark)

Norrie, Ida Christine

of age-dependent PD-1+ CD4+ T cells was therefore investigated as well as its importance for development of PD-1+ CD4+ T cells during leukemic development. My results showed that loss of C/EBPα expression in the lymphoid compartment led to an increased amount of aged PD-1+ CD4+ T cells, but not of young...... PD-1+ CD4+ T cells, suggesting that C/EBPα repress the accumulation of these cells in old mice. Furthermore, C/EBPα-deficiency in the lymphoid compartment had no effect on leukemic development and did not affect the accumulation of PD-1+ CD4+ T cells during development of leukemia. M data indicates......The Ph.D. thesis comprises two projects: (1) C/EBPα is dispensable for the ontogeny of PD1+ CD4+ memory T cells, but restricts their expansion in an age-dependent manner. (2) Modulation of RNR activity prolongs survival of mice with AML. Immunosenescence is a condition of the immune system...

SALL4, a stem cell factor, affects the side population by regulation of the ATP-binding cassette drug transport genes.

Directory of Open Access Journals (Sweden)

Ha-Won Jeong

2011-04-01

Full Text Available Our previous work shows that the stem cell factor SALL4 plays a central role in embryonic and leukemic stem cells. In this study, we report that SALL4 expression was higher in drug resistant primary acute myeloid leukemic patients than those from drug-responsive cases. In addition, while overexpression of SALL4 led to drug resistance in cell lines, cells with decreased SALL4 expression were more sensitive to drug treatments than the parental cells. This led to our investigation of the implication of SALL4 in drug resistance and its role in side population (SP cancer stem cells. SALL4 expression was higher in SP cells compared to non-SP cells by 2-4 fold in various malignant hematopoietic cell lines. Knocking down of SALL4 in isolated SP cells resulted in a reduction of SP cells, indicating that SALL4 is required for their self-renewal. The SP phenotype is known to be mediated by members of the ATP-binding cassette (ABC drug transport protein family, such as ABCG2 and ABCA3. Using chromatin-immunoprecipitation (ChIP, quantitative reverse transcription polymerase chain reaction (qRT-PCR and electrophoretic mobility shift assay(EMSA, we demonstrated that SALL4 was able to bind to the promoter region of ABCA3 and activate its expression while regulating the expression of ABCG2 indirectly. Furthermore, SALL4 expression was positively correlated to those of ABCG2 and ABCA3 in primary leukemic patient samples. Taken together, our results suggest a novel role for SALL4 in drug sensitivity, at least in part through the maintenance of SP cells, and therefore may be responsible for drug-resistance in leukemia. We are the first to demonstrate a direct link between stem cell factor SALL4, SP and drug resistance in leukemia.

HUMAN NK CELLS: FROM SURFACE RECEPTORS TO THE THERAPY OF LEUKEMIAS AND SOLID TUMORS

Directory of Open Access Journals (Sweden)

LORENZO eMORETTA

2014-03-01

Full Text Available Natural Killer (NK cells are major effector cells of the innate immunity. The discovery, over two decades ago, of MHC-class I specific NK receptors and subsequently of activating receptors, recognizing ligands expressed by tumor or virus-infected cells, paved the way to our understanding of the mechanisms of selective recognition and killing of tumor cells. Although NK cells can efficiently kill tumor cells of different histotypes in vitro, their activity may be limited in vivo by their inefficient trafficking to tumor lesions and by the inhibition of their function induced by tumor cells themselves and by the tumor microenvironment. On the other hand, the important role of NK cells has been clearly demonstrated in the therapy of high risk leukemias in the haploidentical hematopoietic cell (HSC transplantation setting. NK cells derived from donor HSC kill leukemic cells residual after the conditioning regimen, thus preventing leukemia relapses. In addition, they also kill residual dendritic cells and T lymphocytes, thus preventing both GvHD and graft rejection.

Antileukemic Potential of Momordica charantia Seed Extracts on Human Myeloid Leukemic HL60 Cells

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Ramani Soundararajan

2012-01-01

Full Text Available Momordica charantia (bitter gourd has been used in the traditional system of medicine for the treatment of various diseases. Anticancer activity of M. charantia extracts has been demonstrated by numerous in vitro and in vivo studies. In the present study, we investigated the differentiation inducing potential of fractionated M. charantia seed extracts in human myeloid HL60 cells. We found that the HL60 cells treated with the fractionated seed extracts differentiated into granulocytic lineage as characterized by NBT staining, CD11b expression, and specific esterase activity. The differentiation inducing principle was found to be heat-stable, and organic in nature. The differentiation was accompanied by a downregulation of c-myc transcript, indicating the involvement of c-myc pathway, at least in part, in differentiation. Taken together these results indicate that fractionated extracts of M. charantia seeds possess differentiation inducing activity and therefore can be evaluated for their potential use in differentiation therapy for leukemia in combination with other inducers of differentiation.

Antileukemic Potential of Momordica charantia Seed Extracts on Human Myeloid Leukemic HL60 Cells

Science.gov (United States)

Soundararajan, Ramani; Prabha, Punit; Rai, Umesh; Dixit, Aparna

2012-01-01

Momordica charantia (bitter gourd) has been used in the traditional system of medicine for the treatment of various diseases. Anticancer activity of M. charantia extracts has been demonstrated by numerous in vitro and in vivo studies. In the present study, we investigated the differentiation inducing potential of fractionated M. charantia seed extracts in human myeloid HL60 cells. We found that the HL60 cells treated with the fractionated seed extracts differentiated into granulocytic lineage as characterized by NBT staining, CD11b expression, and specific esterase activity. The differentiation inducing principle was found to be heat-stable, and organic in nature. The differentiation was accompanied by a downregulation of c-myc transcript, indicating the involvement of c-myc pathway, at least in part, in differentiation. Taken together these results indicate that fractionated extracts of M. charantia seeds possess differentiation inducing activity and therefore can be evaluated for their potential use in differentiation therapy for leukemia in combination with other inducers of differentiation. PMID:22654956

Clonal proliferation and karyotypic features of cells in bone marrow after irradiation

International Nuclear Information System (INIS)

Kohno, S.; Ishihara, T.

1979-01-01

Single stem cells in which chromosome abnormalities are induced by radiation may multiply to form the chromosomally abnormal clones of cells that may replace most of the cells in regenerating hematopoietic tissues after irradiation. It is only a limited number of karyotypes out of a variety of the cells with radiation-induced chromosome abnormalities that can persist as proliferative clones. Such clones in the bone marrows of irradiated rats were found to have aneusomic chromosome constitutions with trisomy or monosomy. This finding is contradictory to the general beliefs that the chromosomally abnormal clones surviving after irradiation would have the chromosome constitutions comparable to a normal diploid set making such clone cells selectively neutral, and that autosomally monosomic cells would not be able to compete against the cells in normal somatic tissues. The proliferation of aneusomic cells in hematopoietic tissues is a phenomenon observable in various blood disorders such as leukemia. The fact that almost all of the aneuploid clones observed possessed various chromosomal rearrangements in addition to their numerical changes appears to indicate that the chromosomal imbalance in original clones may predispose their chromosomes to non-disjunction. The process of the leukemic development of cells may require two steps: the leukemic transformation of cells and the proliferation of such transformed cells up to the manifestation of the disease. (Yamashita, S.)

ZFP521 regulates murine hematopoietic stem cell function and facilitates MLL-AF9 leukemogenesis in mouse and human cells.

Science.gov (United States)

Garrison, Brian S; Rybak, Adrian P; Beerman, Isabel; Heesters, Balthasar; Mercier, Francois E; Scadden, David T; Bryder, David; Baron, Roland; Rossi, Derrick J

2017-08-03

The concept that tumor-initiating cells can co-opt the self-renewal program of endogenous stem cells as a means of enforcing their unlimited proliferative potential is widely accepted, yet identification of specific factors that regulate self-renewal of normal and cancer stem cells remains limited. Using a comparative transcriptomic approach, we identify ZNF521 / Zfp521 as a conserved hematopoietic stem cell (HSC)-enriched transcription factor in human and murine hematopoiesis whose function in HSC biology remains elusive. Competitive serial transplantation assays using Zfp521 -deficient mice revealed that ZFP521 regulates HSC self-renewal and differentiation. In contrast, ectopic expression of ZFP521 in HSCs led to a robust maintenance of progenitor activity in vitro. Transcriptional analysis of human acute myeloid leukemia (AML) patient samples revealed that ZNF521 is highly and specifically upregulated in AMLs with MLL translocations. Using an MLL-AF9 murine leukemia model and serial transplantation studies, we show that ZFP521 is not required for leukemogenesis, although its absence leads to a significant delay in leukemia onset. Furthermore, knockdown of ZNF521 reduced proliferation in human leukemia cell lines possessing MLL-AF9 translocations. Taken together, these results identify ZNF521/ZFP521 as a critical regulator of HSC function, which facilitates MLL-AF9-mediated leukemic disease in mice.

A radiolabeled antibody targeting CD123+ leukemia stem cells – initial radioimmunotherapy studies in NOD/SCID mice engrafted with primary human AML

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Jeffrey V. Leyton

2015-01-01

Full Text Available Radioimmunotherapy (RIT with anti-CD123 monoclonal antibody CSL360 modified with nuclear translocation sequence (NLS peptides and labeled with the Auger electron-emitter, 111In (111In-NLS-CSL360 was studied in the prevalent NOD/SCID mouse AML engraftment assay. Significant decreases in CD123+ leukemic cells and impairment of leukemic stem cell self-renewal were achieved with high doses of RIT. However, NOD/SCID mice were very radiosensitive to these doses. At low non-toxic treatment doses, 111In-NLS-CSL360 demonstrated a trend towards improved survival associated with decreased spleen/body weight ratio, an indicator of leukemia burden, and almost complete eradication of leukemia from the bone marrow in some mice.

Development of Single Cell Raman Spectroscopy for Cancer Screening and Therapy Monitoring

Energy Technology Data Exchange (ETDEWEB)

Chan, James W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

2009-02-24

The overall goal of this project was to develop a new technology for cancer detection based on single cell laser tweezers Raman spectroscopy (LTRS). This method has the potential to improve the detection of cancer characteristics in single cells by acquiring cellular spectral markers that reflect the intrinsic biology of the cell. These spectral biomarkers are a new form of molecular signatures in the field of cancer research that may hold promise in accurately identifying and diagnosing cancer and measuring patient response to treatment. The primary objectives of this proposed work were to perform a full characterization of the Raman spectra of single normal, transformed, and cancer cells to identify cancer spectral signatures, validate the clinical significance of these results by direct correlation to established clinical parameters for assessing cancer, and to develop the optical technology needed for efficient sampling and analysis of cells needed for the practical use of such a system in the clinic. The results indicated that normal T and B lymphocytes could be distinguished from their neoplastic cultured cells and leukemia patient cells with classification sensitivities and specificities routinely exceeding 90% based on multivariate statistical analysis and leave-one-out cross validation. Differences primarily in the Raman peaks associated with DNA and protein were observed between normal and leukemic cells and were consistent for both the cultured and primary cells. Differences between normal and leukemia patient cells were more subtle than between normal and leukemia cultured cells but were still significant to allow for accurate discrimination. Furthermore, it is revealed that the spectral differences are representative of the neoplastic phenotype of the cells and not a reflection of the different metabolic states (resting versus active) of normal and leukemic cells. The effect of different standard cell fixation protocols (i.e. methanol, paraformaledhye

Targeting Aberrant Glutathione Metabolism to Eradicate Human Acute Myelogenous Leukemia Cells*

Science.gov (United States)

Pei, Shanshan; Minhajuddin, Mohammad; Callahan, Kevin P.; Balys, Marlene; Ashton, John M.; Neering, Sarah J.; Lagadinou, Eleni D.; Corbett, Cheryl; Ye, Haobin; Liesveld, Jane L.; O'Dwyer, Kristen M.; Li, Zheng; Shi, Lei; Greninger, Patricia; Settleman, Jeffrey; Benes, Cyril; Hagen, Fred K.; Munger, Joshua; Crooks, Peter A.; Becker, Michael W.; Jordan, Craig T.

2013-01-01

The development of strategies to eradicate primary human acute myelogenous leukemia (AML) cells is a major challenge to the leukemia research field. In particular, primitive leukemia cells, often termed leukemia stem cells, are typically refractory to many forms of therapy. To investigate improved strategies for targeting of human AML cells we compared the molecular mechanisms regulating oxidative state in primitive (CD34+) leukemic versus normal specimens. Our data indicate that CD34+ AML cells have elevated expression of multiple glutathione pathway regulatory proteins, presumably as a mechanism to compensate for increased oxidative stress in leukemic cells. Consistent with this observation, CD34+ AML cells have lower levels of reduced glutathione and increased levels of oxidized glutathione compared with normal CD34+ cells. These findings led us to hypothesize that AML cells will be hypersensitive to inhibition of glutathione metabolism. To test this premise, we identified compounds such as parthenolide (PTL) or piperlongumine that induce almost complete glutathione depletion and severe cell death in CD34+ AML cells. Importantly, these compounds only induce limited and transient glutathione depletion as well as significantly less toxicity in normal CD34+ cells. We further determined that PTL perturbs glutathione homeostasis by a multifactorial mechanism, which includes inhibiting key glutathione metabolic enzymes (GCLC and GPX1), as well as direct depletion of glutathione. These findings demonstrate that primitive leukemia cells are uniquely sensitive to agents that target aberrant glutathione metabolism, an intrinsic property of primary human AML cells. PMID:24089526

Structural features of nucleoli in blood, leukemic, lymphoma and myeloma cells

Directory of Open Access Journals (Sweden)

K Smetana

2010-01-01

Full Text Available At present, it seems clear that the nucleolus is multifunctional and represents one of the key cell organelles that participate directly or indirectly in cell resting, proliferation, differentiation and maturation states, and possibly also in programmed cell death. Thus, the morphology and cytochemistry of nucleoli may represent a very useful tool not only for the evaluation of nucleolar biosynthetic activities but also for the evaluation of various cell states under physiological, experimental and pathological conditions.

ArtinM Mediates Murine T Cell Activation and Induces Cell Death in Jurkat Human Leukemic T Cells

Science.gov (United States)

Oliveira-Brito, Patrícia Kellen Martins; Gonçalves, Thiago Eleutério; Vendruscolo, Patrícia Edivânia; Roque-Barreira, Maria Cristina

2017-01-01

The recognition of cell surface glycans by lectins may be critical for the innate and adaptive immune responses. ArtinM, a d-mannose-binding lectin from Artocarpus heterophyllus, activates antigen-presenting cells by recognizing TLR2 N-glycans and induces Th1 immunity. We recently demonstrated that ArtinM stimulated CD4+ T cells to produce proinflammatory cytokines. Here, we further studied the effects of ArtinM on adaptive immune cells. We showed that ArtinM activates murine CD4+ and CD8+ T cells, augmenting their positivity for CD25, CD69, and CD95 and showed higher interleukin (IL)-2 and interferon (IFN)-γ production. The CD4+ T cells exhibited increased T-bet expression in response to ArtinM, and IL-2 production by CD4+ and CD8+ T cells depended on the recognition of CD3εγ-chain glycans by ArtinM. The ArtinM effect on aberrantly-glycosylated neoplastic lymphocytes was studied in Jurkat T cells, in which ArtinM induced IL-2, IFN-γ, and IL-1β production, but decreased cell viability and growth. A higher frequency of AnnexinV- and propidium iodide-stained cells demonstrated the induction of Jurkat T cells apoptosis by ArtinM, and this apoptotic response was reduced by caspases and protein tyrosine kinase inhibitors. The ArtinM effects on murine T cells corroborated with the immunomodulatory property of lectin, whereas the promotion of Jurkat T cells apoptosis may reflect a potential applicability of ArtinM in novel strategies for treating lymphocytic leukemia. PMID:28665310

Allele-specific gene expression patterns in primary leukemic cells reveal regulation of gene expression by CpG site methylation

DEFF Research Database (Denmark)

Milani, Lili; Lundmark, Anders; Nordlund, Jessica

2008-01-01

To identify genes that are regulated by cis-acting functional elements in acute lymphoblastic leukemia (ALL) we determined the allele-specific expression (ASE) levels of 2, 529 genes by genotyping a genome-wide panel of single nucleotide polymorphisms in RNA and DNA from bone marrow and blood...

Brain-specific enhancers for cell-based therapy

Science.gov (United States)

Visel, Axel; Rubenstein, John L.R.; Chen, Ying-Jiun; Pennacchio, Len A.; Vogt, Daniel; Nicholas, Cory; Kriegstein, Arnold

2018-04-24

Herein are described a set of novel specific human enhancers for specific forebrain cell types used to study and select for human neural progenitor cells. This approach enables the ability to generate interneurons from human ES, iPS and iN cells, making them available for human transplantation and for molecular/cellular analyzes. These approaches are also directly applicable to generating other neuronal cell types, such as cortical and striatal projection neurons, which have implications for many human diseases.

Natural killer cells facilitate PRAME-specific T-cell reactivity against neuroblastoma

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Spel, Lotte; Boelens, Jaap-Jan; van der Steen, Dirk M.; Blokland, Nina J.G.; van Noesel, Max M.; Molenaar, Jan J.; Heemskerk, Mirjam H.M.

2015-01-01

Neuroblastoma is the most common solid tumor in children with an estimated 5-year progression free survival of 20–40% in stage 4 disease. Neuroblastoma actively avoids recognition by natural killer (NK) cells and cytotoxic T lymphocytes (CTLs). Although immunotherapy has gained traction for neuroblastoma treatment, these immune escape mechanisms restrain clinical results. Therefore, we aimed to improve neuroblastoma immunogenicity to further the development of antigen-specific immunotherapy against neuroblastoma. We found that neuroblastoma cells significantly increase surface expression of MHC I upon exposure to active NK cells which thereby readily sensitize neuroblastoma cells for recognition by CTLs. We show that oncoprotein PRAME serves as an immunodominant antigen for neuroblastoma as NK-modulated neuroblastoma cells are recognized by PRAMESLLQHLIGL/A2-specific CTL clones. Furthermore, NK cells induce MHC I upregulation in neuroblastoma through contact-dependent secretion of IFNγ. Our results demonstrate remarkable plasticity in the peptide/MHC I surface expression of neuroblastoma cells, which is reversed when neuroblastoma cells experience innate immune attack by sensitized NK cells. These findings support the exploration of NK cells as adjuvant therapy to enforce neuroblastoma-specific CTL responses. PMID:26452036

Induction of specific suppressor T cells in vitro

International Nuclear Information System (INIS)

Eardley, D.D.; Gershon, R.K.

1976-01-01

We describe conditions for generating sheep red blood cell-specific suppressor T cells in Mishell-Dutton cultures. The production of specific suppressor cells is favored by increasing antigen dose in the initial culture but can be produced by transferring more cells when lower doses of antigen are used. Transfer of small numbers of cells cultured with low doses of antigen leads to a specific helper effect. Transfer of large numbers of educated cells leads to nonspecific suppression. Suppression can be effected by the effluent cells from nylon wool columns which do not make detectable PFC. A fraction of these cells become resistant to treatment with anti-T cell sera and complement after culture. The suppressor cells are radiation sensitive and must be able to synthesize protein to suppress. They take 2 to 3 days of education to reach maximum suppressive efficiency and will not suppress cultures if added 2 to 3 days after culture initiation. Their production is favored by the absence of mercaptoethanol, suggesting that the observed suppression is not ''too much help.'' The ability to generate specific suppressor cells in vitro should be of great benefit in determining the factors that regulate their appearance in vivo

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

Fc-receptors and surface immunoglobulins in cells of the hairy cell leukemia

International Nuclear Information System (INIS)

Rieber, E.P.; Linke, R.P.; Riethmueller, G.; Heyden, H.W. von; Waller, H.D.

1976-01-01

Using 125 I-labelled aggregated IgG in a quantitative assay a strong expression of Fc-receptors was found on the leukemic cells of a patient with hairy cell leukemia. The Fc-receptor activity on these cells was much higher than that on monocytes and B-lymphocytes from normal blood. Surface immunoglobulins were detected by radioautography using radioactively labelled (Fab') 2 -fragments of monospecific antibodies directed against immunoglobulin heavy chains. Prior to radioautography the cells were stained for the tartrate resistant acid phosphatase. It is found that all cells containing this enzyme bore delta-chains on their surface. On more than 90% of these cells a simultaneous expression of μ-chains was detected. γ-chains could only be demonstrated on cells which were negative for the tartrate resistant acid phosphatase; part of these cells, however, were hairy cells by morphological criteria. (orig.) [de

Fc-receptors and surface immunoglobulins in cells of the hairy cell leukemia

Energy Technology Data Exchange (ETDEWEB)

Rieber, E P; Linke, R P; Riethmueller, G [Tuebingen Univ. (Germany, F.R.). Abt. fuer Experimentelle Chirurgie und Immunologie; Heyden, H.W. von; Waller, H D [Tuebingen Univ. (Germany, F.R.). Abt. Innere Medizin 2

1976-01-01

Using /sup 125/I-labelled aggregated IgG in a quantitative assay a strong expression of Fc-receptors was found on the leukemic cells of a patient with hairy cell leukemia. The Fc-receptor activity on these cells was much higher than that on monocytes and B-lymphocytes from normal blood. Surface immunoglobulins were detected by radioautography using radioactively labelled (Fab')/sub 2/-fragments of monospecific antibodies directed against immunoglobulin heavy chains. Prior to radioautography the cells were stained for the tartrate resistant acid phosphatase. It is found that all cells containing this enzyme bore delta-chains on their surface. On more than 90% of these cells a simultaneous expression of ..mu..-chains was detected. ..gamma..-chains could only be demonstrated on cells which were negative for the tartrate resistant acid phosphatase; part of these cells, however, were hairy cells by morphological criteria.

Stability and bifurcation in a model for the dynamics of stem-like cells in leukemia under treatment

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Rǎdulescu, I. R.; Cândea, D.; Halanay, A.

2012-11-01

A mathematical model for the dynamics of leukemic cells during treatment is introduced. Delay differential equations are used to model cells' evolution and are based on the Mackey-Glass approach, incorporating Goldie-Coldman law. Since resistance is propagated by cells that have the capacity of self-renewal, a population of stem-like cells is studied. Equilibrium points are calculated and their stability properties are investigated.

Glucocorticoids and Polyamine Inhibitors Synergize to Kill Human Leukemic CEM Cells

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Aaron L. Miller

2002-01-01

Full Text Available Glucocorticoids are well-known apoptotic agents in certain classes of lymphoid cell malignancies. Reduction of intracellular polyamine levels by use of inhibitors that block polyamine synthesis slows or inhibits growth of many cells in vitro. Several such inhibitors have shown efficacy in clinical trials, though the toxicity of some compounds has limited their usefulness. We have tested the effects of combinations of the glucocorticoid dexamethasone. (20Dex and two polyamine inhibitors, difluoromethylornithine. (20DFMO and methyl glyoxal bis guanylhydrazone. (20MGBG, on the clonal line of human acute lymphoblastic leukemia cells, CEM-C7-14. Dex alone kills these cells, though only after a delay of at least 24 hours. We also evaluated a partially glucocorticoid-resistant c-Myc-expressing CEM-C7-14 clone. We show that Dex downregulates ornithine decarboxylase. (20ODC, the rate-limiting enzyme in polyamine synthesis. Pretreatment with the ODC inhibitor DFMO, followed by addition of Dex, enhances steroid-evoked kill slightly. The combination of pretreatment with sublethal concentrations of both DFMO and the inhibitor of S-adenosylmethionine decarboxylase, MGBG, followed by addition of Dex, results in strong synergistic cell kill. Both the rapidity and extent of cell kill are enhanced compared to the effects of Dex alone. These results suggest that use of such combinations in vivo may result in apoptosis of malignant cells with lower overall toxicity.

Ubiquitin-specific protease 14 regulates cell proliferation and apoptosis in oral squamous cell carcinoma.

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Chen, Xiangyun; Wu, Jingjing; Chen, Yitian; Ye, Dongxia; Lei, Hu; Xu, Hanzhang; Yang, Li; Wu, Yingli; Gu, Wenli

2016-10-01

Ubiquitin-specific protease 14, a deubiquitinating enzyme, has been implicated in the tumorigenesis and progression of several cancers, but its role in oral squamous cell carcinoma remains to be elucidated. The aim of this study was to explore the expression pattern and roles of Ubiquitin-specific protease 14 in the occurrence and development of oral squamous cell carcinoma. Interestingly, Ubiquitin-specific protease 14 was overexpressed in oral cancer tissues and cell lines at both mRNA and protein levels. b-AP15, a specific inhibitor of Ubiquitin-specific protease 14, significantly inhibited the growth of cancer cells and increased cell apoptosis in a dose-dependent manner. Moreover, knockdown of Ubiquitin-specific protease 14 by shRNA significantly inhibited the proliferation and migration of cancer cells in vitro. Finally, using a xenograft mouse model of oral squamous cell carcinoma, knockdown of Ubiquitin-specific protease 14 markedly inhibited tumor growth and triggered the cancer cell apoptosis in vivo, supporting previous results. In conclusion, for the first time we have demonstrated the expression pattern of Ubiquitin-specific protease 14 in oral squamous cell carcinoma and verified a relationship with tumor growth and metastasis. These results may highlight new therapeutic strategies for tumor treatment, application of Ubiquitin-specific protease 14 selective inhibitor, such as b-AP15, or knockdown by shRNA. Collectively, Ubiquitin-specific protease 14 could be a potential therapeutic target for oral squamous cell carcinoma patients. Copyright © 2016 Elsevier Ltd. All rights reserved.

Synergistic apoptosis of CML cells by buthionine sulfoximine and hydroxychavicol correlates with activation of AIF and GSH-ROS-JNK-ERK-iNOS pathway.

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Avik Acharya Chowdhury

Full Text Available BACKGROUND: Hydroxychavicol (HCH, a constituent of Piper betle leaf has been reported to exert anti-leukemic activity through induction of reactive oxygen species (ROS. The aim of the study is to optimize the oxidative stress -induced chronic myeloid leukemic (CML cell death by combining glutathione synthesis inhibitor, buthionine sulfoximine (BSO with HCH and studying the underlying mechanism. MATERIALS AND METHODS: Anti-proliferative activity of BSO and HCH alone or in combination against a number of leukemic (K562, KCL22, KU812, U937, Molt4, non-leukemic (A549, MIA-PaCa2, PC-3, HepG2 cancer cell lines and normal cell lines (NIH3T3, Vero was measured by MTT assay. Apoptotic activity in CML cell line K562 was detected by flow cytometry (FCM after staining with annexin V-FITC/propidium iodide (PI, detection of reduced mitochondrial membrane potential after staining with JC-1, cleavage of caspase- 3 and poly (ADP-ribose polymerase proteins by western blot analysis and translocation of apoptosis inducing factor (AIF by confocal microscopy. Intracellular reduced glutathione (GSH was measured by colorimetric assay using GSH assay kit. 2',7'-dichlorodihydrofluorescein diacetate (DCF-DA and 4-amino-5-methylamino-2',7'-difluorofluorescein (DAF-FM were used as probes to measure intracellular increase in ROS and nitric oxide (NO levels respectively. Multiple techniques like siRNA transfection and pharmacological inhibition were used to understand the mechanisms of action. RESULTS: Non-apoptotic concentrations of BSO significantly potentiated HCH-induced apoptosis in K562 cells. BSO potentiated apoptosis-inducing activity of HCH in CML cells by caspase-dependent as well as caspase-independent but apoptosis inducing factor (AIF-dependent manner. Enhanced depletion of intracellular GSH induced by combined treatment correlated with induction of ROS. Activation of ROS- dependent JNK played a crucial role in ERK1/2 activation which subsequently induced the

Cancer Patient T Cells Genetically Targeted to Prostate-Specific Membrane Antigen Specifically Lyse Prostate Cancer Cells and Release Cytokines in Response to Prostate-Specific Membrane Antigen

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Michael C. Gong

1999-06-01

Full Text Available The expression of immunoglobulin-based artificial receptors in normal T lymphocytes provides a means to target lymphocytes to cell surface antigens independently of major histocompatibility complex restriction. Such artificial receptors have been previously shown to confer antigen-specific tumoricidal properties in murine T cells. We constructed a novel ζ chain fusion receptor specific for prostate-specific membrane antigen (PSMA termed Pz-1. PSMA is a cell-surface glycoprotein expressed on prostate cancer cells and the neovascular endothelium of multiple carcinomas. We show that primary T cells harvested from five of five patients with different stages of prostate cancer and transduced with the Pz-1 receptor readily lyse prostate cancer cells. Having established a culture system using fibroblasts that express PSMA, we next show that T cells expressing the Pz-1 receptor release cytokines in response to cell-bound PSMA. Furthermore, we show that the cytokine release is greatly augmented by B7.1-mediated costimulation. Thus, our findings support the feasibility of adoptive cell therapy by using genetically engineered T cells in prostate cancer patients and suggest that both CD4+ and CD8+ T lymphocyte functions can be synergistically targeted against tumor cells.

Blockade of CD7 expression in T cells for effective chimeric antigen receptor targeting of T-cell malignancies.

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Png, Yi Tian; Vinanica, Natasha; Kamiya, Takahiro; Shimasaki, Noriko; Coustan-Smith, Elaine; Campana, Dario

2017-11-28

Effective immunotherapies for T-cell malignancies are lacking. We devised a novel approach based on chimeric antigen receptor (CAR)-redirected T lymphocytes. We selected CD7 as a target because of its consistent expression in T-cell acute lymphoblastic leukemia (T-ALL), including the most aggressive subtype, early T-cell precursor (ETP)-ALL. In 49 diagnostic T-ALL samples (including 14 ETP-ALL samples), median CD7 expression was >99%; CD7 expression remained high at relapse (n = 14), and during chemotherapy (n = 54). We targeted CD7 with a second-generation CAR (anti-CD7-41BB-CD3ζ), but CAR expression in T lymphocytes caused fratricide due to the presence of CD7 in the T cells themselves. To downregulate CD7 and control fratricide, we applied a new method (protein expression blocker [PEBL]), based on an anti-CD7 single-chain variable fragment coupled with an intracellular retention domain. Transduction of anti-CD7 PEBL resulted in virtually instantaneous abrogation of surface CD7 expression in all transduced T cells; 2.0% ± 1.7% were CD7 + vs 98.1% ± 1.5% of mock-transduced T cells (n = 5; P < .0001). PEBL expression did not impair T-cell proliferation, interferon-γ and tumor necrosis factor-α secretion, or cytotoxicity, and eliminated CAR-mediated fratricide. PEBL-CAR T cells were highly cytotoxic against CD7 + leukemic cells in vitro and were consistently more potent than CD7 + T cells spared by fratricide. They also showed strong anti-leukemic activity in cell line- and patient-derived T-ALL xenografts. The strategy described in this study fits well with existing clinical-grade cell manufacturing processes and can be rapidly implemented for the treatment of patients with high-risk T-cell malignancies.

A comparison of caspase 3 expression in the endocrine and exocrine parts of the pancreas after cladribine application according to the "leukemic" schema

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Jasinski Ludwik

2017-03-01

Full Text Available The therapeutic effects of the immunosuppressive agent, cladribine, have been demonstrated by its toxicity to cells. However, its effects on healthy cells of the body is poorly understood. The aim of study was, hence, to, firstly, evaluate the morphology of the endocrine and exocrine pancreas after the administration of cladribine according to the "leukemic" schema, and, secondly, to assess its impact on the intensity of apoptosis. The experiment was carried out on female Wistar rats which were placed within the control group KA, and the experimental groups: A and A-bis. In the experimental groups, Cladribine was administered according to the cycle used to treat human hairy cell leukemia. In group A, the material was taken 24 hours after administration of the last dose of the drug, while in group A-bis, this was done after a 4 weeks break. The reaction was assessed to be average in 80% of all cells in group A, and in 64% of all acinar cells in group KA, while in group A-bis, the majority of the exocrine cells demonstrated a lack of immunohistochemical response (72%. Moreover, most endocrine cells (60% in group A-bis revealed a strong reaction, while in Group A, the corresponding figure is a little over 34%. A comparison of the severity of the caspase 3 expression in both the exocrine and endocrine pancreas showed significant differentiation results between the group KA and group A-bis, and between group A and A-bis (p < 0.0001. In can be concluded that endocrine cells are more sensitive to cladribine than are exocrine cells.

The ROS/SUMO Axis Contributes to the Response of Acute Myeloid Leukemia Cells to Chemotherapeutic Drugs

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Guillaume Bossis

2014-06-01

Full Text Available Chemotherapeutic drugs used in the treatment of acute myeloid leukemias (AMLs are thought to induce cancer cell death through the generation of DNA double-strand breaks. Here, we report that one of their early effects is the loss of conjugation of the ubiquitin-like protein SUMO from its targets via reactive oxygen species (ROS-dependent inhibition of the SUMO-conjugating enzymes. Desumoylation regulates the expression of specific genes, such as the proapoptotic gene DDIT3, and helps induce apoptosis in chemosensitive AMLs. In contrast, chemotherapeutics do not activate the ROS/SUMO axis in chemoresistant cells. However, pro-oxidants or inhibition of the SUMO pathway by anacardic acid restores DDIT3 expression and apoptosis in chemoresistant cell lines and patient samples, including leukemic stem cells. Finally, inhibition of the SUMO pathway decreases tumor growth in mice xenografted with AML cells. Thus, targeting the ROS/SUMO axis might constitute a therapeutic strategy for AML patients resistant to conventional chemotherapies.

Kinetics of antigen specific and non-specific polyclonal B-cell responses during lethal Plasmodium yoelii malaria

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Laurence Rolland

1992-06-01

Full Text Available In order to study the kinetics and composition of the polyclonal B-cell activation associated to malaria infection, antigen-specific and non-specific B-cell responses were evaluated in the spleens of mice infected with Plasmodium yoelii 17 XL or injected with lysed erythrocytes or plasma from P. yoelii infected mice or with P. falciparum culture supernatants. Spleen/body weigth ratio, numbers of nucleated spleen cells and Immunoglobulin-containing and Immunoglobulin-secreting cells increased progressively during the course of infection,in parallel to the parasitemia. A different pattern of kinetics was observed when anti-sheep red blood cell and anti-trinitrophenylated-sheep red blood cell plaque forming cells response were studied: maximum values were observed at early stages of infection, whereas the number of total Immunoglobulin-containing and Immunoglobulin-secreting cells were not yet altered. Conversely, at the end of infection, when these latter values reached their maximum, the anti-sheep red blood cell and anti-trinitrophenylated-sheep red blood cell specific responses were normal or even infranormal. In mice injected with Plasmodium-derived material, a higher increase in antigen-specific PFC was observed, as compared to the increase of Immunoglobulin-containing and Immunoglobulin-secreting cell numbers. This suggested a "preferential" (antigen-plus mitogen-induced stimulation of antigen-specific cells rather than a generalized non-specific (mitogen-induced triggering of B-lymphocytes. On the basis of these and previous results, it is suggested that polyclonal B-cell activation that takes place during the course of infection appears as a result of successive waves of antigen-specific B-cell activation.

IgE antipolymyxin B antibody formation in a T cell-depleted bone marrow transplant patient

International Nuclear Information System (INIS)

Lakin, J.D.; Grace, W.R.; Sell, K.W.

1975-01-01

The production of IgE-class antibody specific for polymyxin B is documented in an 18-year-old white female acute myelocytic leukemic patient in relapse. The patient was rendered T cell--deficient by total-body x irradiation and antihuman thymocyte globulin for the purpose of bone marrow transplantation. Thereafter, symptoms of nasal congestion, rhinorrhea, and perinasal urtication produced by topical application of a polymyxin solution were noted. Reaginic activity mediated by an IgE antibody against polymyxin is documented by Prausnitz-Kuestner--type passive transfer reactions and by an indirect hemagglutination technique developed for these studies. The occurrence of type I hypersensitivity to this topical antibiotic is rare. It is speculated that pharmaceuticals normally having a low sensitizing potential might demonstrate increased reaginic immunogenicity in a spontaneously or iatrogenically T cell-depleted patient

Cell-specific monitoring of protein synthesis in vivo.

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Nikos Kourtis

Full Text Available Analysis of general and specific protein synthesis provides important information, relevant to cellular physiology and function. However, existing methodologies, involving metabolic labelling by incorporation of radioactive amino acids into nascent polypeptides, cannot be applied to monitor protein synthesis in specific cells or tissues, in live specimens. We have developed a novel approach for monitoring protein synthesis in specific cells or tissues, in vivo. Fluorescent reporter proteins such as GFP are expressed in specific cells and tissues of interest or throughout animals using appropriate promoters. Protein synthesis rates are assessed by following fluorescence recovery after partial photobleaching of the fluorophore at targeted sites. We evaluate the method by examining protein synthesis rates in diverse cell types of live, wild type or mRNA translation-defective Caenorhabditis elegans animals. Because it is non-invasive, our approach allows monitoring of protein synthesis in single cells or tissues with intrinsically different protein synthesis rates. Furthermore, it can be readily implemented in other organisms or cell culture systems.

Current and Emerging Therapeutics for Cutaneous T-Cell Lymphoma: Histone Deacetylase Inhibitors

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Annabelle L. Rodd; Katherine Ververis; Tom C. Karagiannis

2012-01-01

Cutaneous T-cell lymphoma is a term that encompasses a spectrum of non-Hodgkin’s T-cell lymphomas with primary manifestations in the skin. It describes a heterogeneous group of neoplasms that are characterised by an accumulation of malignant T cells of the CD4 phenotype that have the propensity to home and accumulate in the skin, lymph nodes, and peripheral blood. The two most common variants of cutaneous T-cell lymphoma include mycosis fungoides and the leukemic variant, the Sézary syndrome....

Angiocrine functions of organ-specific endothelial cells

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Rafii, Shahin; Butler, Jason M; Ding, Bi-Sen

2016-01-01

Preface Endothelial cells lining blood vessel capillaries are not just passive conduits for delivering blood. Tissue-specific endothelium establish specialized vascular niches that deploy specific sets of growth factors, known as angiocrine factors, which actively participate in inducing, specifying, patterning, and guiding organ regeneration and maintaining homeostasis and metabolism. Angiocrine factors upregulated in response to injury orchestrates self-renewal and differentiation of tissue-specific repopulating resident stem and progenitor cells into functional organs. Uncovering the precise mechanisms whereby physiological-levels of angiocrine factors are spatially and temporally produced, and distributed by organotypic endothelium to repopulating cells, will lay the foundation for driving organ repair without scarring. PMID:26791722

A novel cell growth-promoting factor identified in a B cell leukemia cell line, BALL-1

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Dao, T.; Holan, V.; Minowada, J.

1993-01-01

A novel leukemia cell growth-promoting activity has been identified in the culture supernatant from a human B cell leukemia cell line, BALL-1. The supernatant from unstimulated cultures of the BALL-1 cells significantly promoted the growth of 16 out of 24 leukemia/lymphoma cell lines of different lineages (T, B and non-lymphoid) in a minimal concentration of fetal bovine serum (FBS), and 5 out of 12 cases of fresh leukemia cells in FBS-free medium. The growth-promoting sieve filtration and dialysis. The MW of the factor was less than 10 kDa. The growth-promoting activity was heat and acid stable and resistant to trypsin treatment. The factor isolated from the BALL-1 supernatant was distinct from known polypeptide growth factors with MW below 10 kDa, such as epidermal growth factor, transforming growth factor α, insulin-like growth factor I (IGF-I), IGF-II and insulin, as determine by specific antibodies and by cell-growth-promoting tests. The factor is the BALL-1 supernatant did not promote the proliferation of normal human fresh peripheral blood lymphocytes or mouse fibroblast cell line, BALB/C 3T3. In addition to the BALL-1 supernatant, a similar growth-promoting activity was found in the culture supernatant from 13 of 17 leukemia/lymphoma cell lines tested. The activity in these culture supernatant promoted the growth of leukemia/lymphoma cell lines in autocrine and/or paracrine fashions. These observations suggest that the low MW cell growth-promoting activity found in the BALL-1 culture supernatant is mediated by a novel factor which may be responsible for the clonal expansion of particular leukemic clones. (author)

Semiallogenic fusions of MSI+ tumor cells and activated B cells induce MSI-specific T cell responses

International Nuclear Information System (INIS)

Garbe, Yvette; Klier, Ulrike; Linnebacher, Michael

2011-01-01

Various strategies have been developed to transfer tumor-specific antigens into antigen presenting cells in order to induce cytotoxic T cell responses against tumor cells. One approach uses cellular vaccines based on fusions of autologous antigen presenting cells and allogeneic tumor cells. The fusion cells combine antigenicity of the tumor cell with optimal immunostimulatory capacity of the antigen presenting cells. Microsatellite instability caused by mutational inactivation of DNA mismatch repair genes results in translational frameshifts when affecting coding regions. It has been shown by us and others that these mutant proteins lead to the presentation of immunogenic frameshift peptides that are - in principle - recognized by a multiplicity of effector T cells. We chose microsatellite instability-induced frameshift antigens as ideal to test for induction of tumor specific T cell responses by semiallogenic fusions of microsatellite instable carcinoma cells with CD40-activated B cells. Two fusion clones of HCT116 with activated B cells were selected for stimulation of T cells autologous to the B cell fusion partner. Outgrowing T cells were phenotyped and tested in functional assays. The fusion clones expressed frameshift antigens as well as high amounts of MHC and costimulatory molecules. Autologous T cells stimulated with these fusions were predominantly CD4 + , activated, and reacted specifically against the fusion clones and also against the tumor cell fusion partner. Interestingly, a response toward 6 frameshift-derived peptides (of 14 tested) could be observed. Cellular fusions of MSI + carcinoma cells and activated B cells combine the antigen-presenting capacity of the B cell with the antigenic repertoire of the carcinoma cell. They present frameshift-derived peptides and can induce specific and fully functional T cells recognizing not only fusion cells but also the carcinoma cells. These hybrid cells may have great potential for cellular immunotherapy and

Influence of x-rays and UV-light on the presence of oncogene proteins in spleen cells of leukemic mice

International Nuclear Information System (INIS)

Popovic Hadzija, M.; Poljak Blazi, M.

1996-01-01

Proto-oncogenes are involved in growth, defferentiation and proliferation of normal cells, and in process of neoplastic transformation. In genome of normal cells, exist also tumor-suppressor genes, which contribute to cancer when they are inactivated. Those genes are target for carcinogenesis provoked by radiation. However, species specific genetic factors are important in determing which, if any, gene will be transformed by radiation. It is possible to presume that oncogenes are involved in the development of radioresistant phenotype of ML. Because of that, we examined the presence of c-myc protein in ML cells during the growth of ML and after the irradiation of these cells. Also, we examined the presence of tumor-suppressor protein p53, because inactivation or loss of p53 gene is in connection with transformation of cells. ML is strain specific for RFM mice. Spleen cells were tested 9 (nonterminal phase NTP) or 12 days (terminal phase TP) after inoculation of ML. Cells from NTP were also irradiate with x-rays or UV-light. C-myc protein expresse 74.98% spleen cells of healthy RFM mice. Wild type of p53 protein was detected in 60% of these cells, but mp53 was found in only 5.3% of cells. These results could be explained by the role of c-myc and p53 proteins in regulation of biologic processes. A few spleen cells of NTP expressed c-myc (15%) and mp53 (9.6%) proteins. But, in the same phase higher expressions of wp53 protein (30.5%) was found. On the other hand, the number of c-myc positive cells in TP of leukemia explanation lies in connection of c-myc protein and process of programmed cell death (apoptosis). During growth of ML the number of mp53 positive cells increased (to 47.8%), but wp53 positive cells decreased (to13.4%9). Both types of irradiation provoked strong activation of cellular c-myc gene in ML cells of NTP. We found about 95% c-myc positive cells after x-rays and 93% after UV-light

The rarity of ALDH(+) cells is the key to separation of normal versus leukemia stem cells by ALDH activity in AML patients.

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Hoang, Van T; Buss, Eike C; Wang, Wenwen; Hoffmann, Isabel; Raffel, Simon; Zepeda-Moreno, Abraham; Baran, Natalia; Wuchter, Patrick; Eckstein, Volker; Trumpp, Andreas; Jauch, Anna; Ho, Anthony D; Lutz, Christoph

2015-08-01

To understand the precise disease driving mechanisms in acute myeloid leukemia (AML), comparison of patient matched hematopoietic stem cells (HSC) and leukemia stem cells (LSC) is essential. In this analysis, we have examined the value of aldehyde dehydrogenase (ALDH) activity in combination with CD34 expression for the separation of HSC from LSC in 104 patients with de novo AML. The majority of AML patients (80 out of 104) had low percentages of cells with high ALDH activity (ALDH(+) cells; cells (≥1.9%; ALDH-numerous AML). In patients with ALDH-rare AML, normal HSC could be separated by their CD34(+) ALDH(+) phenotype, whereas LSC were exclusively detected among CD34(+) ALDH(-) cells. For patients with ALDH-numerous AML, the CD34(+) ALDH(+) subset consisted mainly of LSC and separation from HSC was not feasible. Functional analyses further showed that ALDH(+) cells from ALDH-numerous AML were quiescent, refractory to ARA-C treatment and capable of leukemic engraftment in a xenogenic mouse transplantation model. Clinically, resistance to chemotherapy and poor long-term outcome were also characteristic for patients with ALDH-numerous AML providing an additional risk-stratification tool. The difference in spectrum and relevance of ALDH activity in the putative LSC populations demonstrates, in addition to phenotypic and genetic, also functional heterogeneity of leukemic cells and suggests divergent roles for ALDH activity in normal HSC versus LSC. By acknowledging these differences our study provides a new and useful tool for prospective identification of AML cases in which separation of HSC from LSC is possible. © 2014 UICC.

Comparison of imatinib, dasatinib, nilotinib and INNO-406 in imatinib-resistant cell lines.

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Deguchi, Yasuyuki; Kimura, Shinya; Ashihara, Eishi; Niwa, Tomoko; Hodohara, Keiko; Fujiyama, Yoshihide; Maekawa, Taira

2008-06-01

We compared the growth-inhibitory effects and inhibition profile of the SRC family kinases (SFKs) of imatinib, dasatinib, nilotinib and INNO-406. Dasatinib exhibited the strongest potency against BCR-ABL with little selectivity over SFKs. Nilotinib exhibited a weaker affinity than the other inhibitors, but was highly specific for ABL and may be useful for the treatment of P-glycoprotein overexpressing leukemic cells. INNO-406 had an intermediate affinity for BCR-ABL between that of dasatinib and nilotinib, and inhibited only SFKs LCK and LYN among SFKs. Both nilotinib and INNO-406 were potent inhibitors of the dasatinib-resistant T315A, F317L and F317V BCR-ABL mutations.

Specific immunotherapy modifies allergen-specific CD4+ T cell responses in an epitope-dependent manner

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Wambre, Erik; DeLong, Jonathan H.; James, Eddie A.; Torres-Chinn, Nadia; Pfützner, Wolfgang; Möbs, Christian; Durham, Stephen R.; Till, Stephen J.; Robinson, David; Kwok, William W.

2014-01-01

Background Understanding the mechanisms by which the immune system induces and controls allergic inflammation at the T cell epitope level is critical for the design of new allergy vaccine strategies. Objective To characterize allergen-specific T cell responses linked with allergy or peripheral tolerance and to determine how CD4+ T cell responses to individual allergen-derived epitopes change over allergen-specific immunotherapy (ASIT). Methods Timothy grass pollen (TGP) allergy was used as a model for studying grass pollen allergies. The breadth, magnitude, epitope hierarchy and phenotype of the DR04:01-restricted TGP-specific T cell responses in ten grass pollen allergic, five non-atopic and six allergy vaccine-treated individuals was determined using an ex vivo pMHCII-tetramer approach. Results CD4+ T cells in allergic individuals are directed to a broad range of TGP epitopes characterized by defined immunodominance hierarchy patterns and with distinct functional profiles that depend on the epitope recognized. Epitopes that are restricted specifically to either TH2 or TH1/TR1 responses were identified. ASIT was associated with preferential deletion of allergen-specific TH2 cells and without significant change in frequency of TH1/TR1 cells. Conclusions Preferential allergen-specific TH2-cells deletion after repeated high doses antigen stimulation can be another independent mechanism to restore tolerance to allergen during immunotherapy. PMID:24373351

Mucorales-Specific T Cells in Patients with Hematologic Malignancies.

Science.gov (United States)

Potenza, Leonardo; Vallerini, Daniela; Barozzi, Patrizia; Riva, Giovanni; Gilioli, Andrea; Forghieri, Fabio; Candoni, Anna; Cesaro, Simone; Quadrelli, Chiara; Maertens, Johan; Rossi, Giulio; Morselli, Monica; Codeluppi, Mauro; Mussini, Cristina; Colaci, Elisabetta; Messerotti, Andrea; Paolini, Ambra; Maccaferri, Monica; Fantuzzi, Valeria; Del Giovane, Cinzia; Stefani, Alessandro; Morandi, Uliano; Maffei, Rossana; Marasca, Roberto; Narni, Franco; Fanin, Renato; Comoli, Patrizia; Romani, Luigina; Beauvais, Anne; Viale, Pier Luigi; Latgè, Jean Paul; Lewis, Russell E; Luppi, Mario

2016-01-01

Invasive mucormycosis (IM) is an emerging life-threatening fungal infection. It is difficult to obtain a definite diagnosis and to initiate timely intervention. Mucorales-specific T cells occur during the course of IM and are involved in the clearance of the infection. We have evaluated the feasibility of detecting Mucorales-specific T cells in hematological patients at risk for IM, and have correlated the detection of such cells with the clinical conditions of the patients. By using an enzyme linked immunospot assay, the presence of Mucorales-specific T cells in peripheral blood (PB) samples has been investigated at three time points during high-dose chemotherapy for hematologic malignancies. Mucorales-specific T cells producing interferon-γ, interleukin-10 and interleukin-4 were analysed in order to detect a correlation between the immune response and the clinical picture. Twenty-one (10.3%) of 204 patients, accounting for 32 (5.3%) of 598 PB samples, tested positive for Mucorales-specific T cells. Two groups could be identified. Group 1, including 15 patients without signs or symptoms of invasive fungal diseases (IFD), showed a predominance of Mucorales-specific T cells producing interferon-gamma. Group 2 included 6 patients with a clinical picture consistent with invasive fungal disease (IFD): 2 cases of proven IM and 4 cases of possible IFD. The proven patients had significantly higher number of Mucorales-specific T cells producing interleukin-10 and interleukin-4 and higher rates of positive samples by using derived diagnostic cut-offs when compared with the 15 patients without IFD. Mucorales-specific T cells can be detected and monitored in patients with hematologic malignancies at risk for IM. Mucorales-specific T cells polarized to the production of T helper type 2 cytokines are associated with proven IM and may be evaluated as a surrogate diagnostic marker for IM.

Mucorales-Specific T Cells in Patients with Hematologic Malignancies.

Directory of Open Access Journals (Sweden)

Leonardo Potenza

Full Text Available Invasive mucormycosis (IM is an emerging life-threatening fungal infection. It is difficult to obtain a definite diagnosis and to initiate timely intervention. Mucorales-specific T cells occur during the course of IM and are involved in the clearance of the infection. We have evaluated the feasibility of detecting Mucorales-specific T cells in hematological patients at risk for IM, and have correlated the detection of such cells with the clinical conditions of the patients.By using an enzyme linked immunospot assay, the presence of Mucorales-specific T cells in peripheral blood (PB samples has been investigated at three time points during high-dose chemotherapy for hematologic malignancies. Mucorales-specific T cells producing interferon-γ, interleukin-10 and interleukin-4 were analysed in order to detect a correlation between the immune response and the clinical picture. Twenty-one (10.3% of 204 patients, accounting for 32 (5.3% of 598 PB samples, tested positive for Mucorales-specific T cells. Two groups could be identified. Group 1, including 15 patients without signs or symptoms of invasive fungal diseases (IFD, showed a predominance of Mucorales-specific T cells producing interferon-gamma. Group 2 included 6 patients with a clinical picture consistent with invasive fungal disease (IFD: 2 cases of proven IM and 4 cases of possible IFD. The proven patients had significantly higher number of Mucorales-specific T cells producing interleukin-10 and interleukin-4 and higher rates of positive samples by using derived diagnostic cut-offs when compared with the 15 patients without IFD.Mucorales-specific T cells can be detected and monitored in patients with hematologic malignancies at risk for IM. Mucorales-specific T cells polarized to the production of T helper type 2 cytokines are associated with proven IM and may be evaluated as a surrogate diagnostic marker for IM.

Ex vivo assays to study self-renewal and long-term expansion of genetically modified primary human acute myeloid leukemia stem cells

NARCIS (Netherlands)

Schuringa, Jan Jacob; Schepers, Hein

2009-01-01

With the emergence of the concept of the leukemia stem cell, assays to study them remain pivotal in understanding (leukemic) stem cell biology. Although the in vivo NOD-SCID xenotransplantation model is still the favored model of choice in most cases, this system has some limitations as well, such

Changing T cell specificity by retroviral T cell receptor display

NARCIS (Netherlands)

Kessels, H. W.; van den Boom, M. D.; Spits, H.; Hooijberg, E.; Schumacher, T. N.

2000-01-01

The diversity of the T cell receptor (TCR) repertoire is limited, because of the processes of positive and negative T cell selection. To obtain T cells with specificities beyond the immune system's capacity, we have developed a strategy for retroviral TCR display. In this approach, a library of T

Cell-type-specific gene delivery into neuronal cells in vitro and in vivo

International Nuclear Information System (INIS)

Parveen, Zahida; Mukhtar, Muhammad; Rafi, Mohammed; Wenger, David A.; Siddiqui, Khwaja M.; Siler, Catherine A.; Dietzschold, Bernhard; Pomerantz, Roger J.; Schnell, Matthias J.; Dornburg, Ralph

2003-01-01

The avian retroviruses reticuloendotheliosis virus strain A (REV-A) and spleen necrosis virus (SNV) are not naturally infectious in human cells. However, REV-A-derived viral vectors efficiently infect human cells when they are pseudotyped with envelope proteins displaying targeting ligands specific for human cell-surface receptors. Here we report that vectors containing the gag region of REV-A and pol of SNV can be pseudotyped with the envelope protein of vesicular stomatitis virus (VSV) and the glycoproteins of different rabies virus (RV) strains. Vectors pseudotyped with the envelope protein of the highly neurotropic RV strain CVS-N2c facilitated cell type-specific gene delivery into mouse and human neurons, but did not infect other human cell types. Moreover, when such vector particles were injected into the brain of newborn mice, only neuronal cells were infected in vivo. Cell-type-specific gene delivery into neurons may present quite specific gene therapy approaches for many degenerative diseases of the brain

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

Science.gov (United States)

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.

shRNA screening identifies JMJD1C as being required for leukemia maintenance

DEFF Research Database (Denmark)

Sroczynska, Patrycja; Cruickshank, V Adam; Bukowski, John-Paul

2014-01-01

Epigenetic regulatory mechanisms are implicated in the pathogenesis of acute myeloid and lymphoid leukemia (AML and ALL). Recent progress suggests that proteins involved in epigenetic control are amenable to drug intervention, but little is known about the cancer-specific dependency on epigenetic...... candidate drug targets identified in these screens was Jmjd1c. Depletion of Jmjd1c impairs growth and colony formation of mouse MLL-AF9 cells in vitro, as well as establishment of leukemia after transplantation. Depletion of JMJD1C impairs expansion and colony formation of human leukemic cell lines......, with the strongest effect observed in the MLL-rearranged ALL cell line, SEM. In both mouse and human leukemic cells, the growth defect upon JMJD1C depletion appears to be primarily due to increased apoptosis, which implicates JMJD1C as a potential therapeutic target in leukemia....

T cell differentiation stages identified by molecular and immunologic analysis of the T cell receptor complex in childhood lymphoblastic leukemia.

Science.gov (United States)

Mirro, J; Kitchingman, G; Behm, F G; Murphy, S B; Goorha, R M

1987-03-01

T cell differentiation was investigated by determining the relationship of T cell receptor (Ti) gene rearrangement and transcription to the expression of surface and cytoplasmic T3 antigen using blast cells from five children with acute lymphoblastic leukemia of thymic origin. Patterns of monoclonal antibody (MoAb) reactivity indicated that these cases were representative of the three recognized stages (I, II, III) of human thymocyte development. The T3 antigen, which becomes linked to the Ti to form a functional T cell receptor complex on mature thymocytes, was expressed on the cell surface in two cases (stage III). However, in the remaining three cases that were surface T3 negative (stages I and II), large amounts of T3 were identified in the cytoplasm by immunoperoxidase staining and flow cytometry. Leukemic blasts from all five patients showed rearranged genes encoding the beta-chain portion of the Ti heterodimer. RNA transcripts of Ti beta-chain genes were also evident in lymphoblasts from all five cases, but transcripts coding for the alpha-chain portion of Ti were found only in cases that expressed T3 on the cell surface. Thus the absence of surface T3 (and presumably Ti) coincides with the absence of Ti alpha-chain RNA, suggesting that transcription of alpha-chain genes is a critical regulatory event in the surface expression of the Ti-T3 complex. Leukemic T cells that rearrange and express Ti beta-chain genes but lack Ti alpha-chain messenger RNA (mRNA) may represent a stage of differentiation analogous to pre-B cells, where heavy-chain immunoglobulin (Ig) genes are rearranged and expressed but light-chain Ig genes are not expressed.

Cell-Specific Aptamers as Emerging Therapeutics

Directory of Open Access Journals (Sweden)

Cindy Meyer

2011-01-01

Full Text Available Aptamers are short nucleic acids that bind to defined targets with high affinity and specificity. The first aptamers have been selected about two decades ago by an in vitro process named SELEX (systematic evolution of ligands by exponential enrichment. Since then, numerous aptamers with specificities for a variety of targets from small molecules to proteins or even whole cells have been selected. Their applications range from biosensing and diagnostics to therapy and target-oriented drug delivery. More recently, selections using complex targets such as live cells have become feasible. This paper summarizes progress in cell-SELEX techniques and highlights recent developments, particularly in the field of medically relevant aptamers with a focus on therapeutic and drug-delivery applications.

A Recombinant Antibody with the Antigen-Specific, Major Histocompatibility Complex-Restricted Specificity of T Cells

Science.gov (United States)

Andersen, Peter S.; Stryhn, Anette; Hansen, Bjarke E.; Fugger, Lars; Engberg, Jan; Buus, Soren

1996-03-01

Specific recognition of peptide/major histocompatibility complex (MHC) molecule complexes by the T-cell receptor is a key reaction in the specific immune response. Antibodies against peptide/MHC complexes would therefore be valuable tools in studying MHC function and T-cell recognition and might lead to novel approaches in immunotherapy. However, it has proven difficult to generate antibodies with the specificity of T cells by conventional hybridoma techniques. Here we report that the phage display technology is a feasible alternative to generate antibodies recognizing specific, predetermined peptide/MHC complexes.